This document proposes a mobile battery swapping service for electric vehicles (EVs) using a battery swapping van. The van carries fully charged batteries and can swap a depleted battery in an EV within a few minutes. First, the document establishes a reasonable EV battery swapping architecture based on the van. It defines the roles of participants like battery producers, chargers, and swapping stations. It also describes the battery swapping process. Second, it analyzes battery swapping service requests and proposes a minimum waiting time scheduling strategy to efficiently schedule requests based on priority and satisfaction. Simulation results show this approach can provide a fast, convenient, and flexible swapping service to ease EV users' range anxiety.
Now India is Implementing with Preference and Priority A Green Carbon Free Silent Road Transportation Electric Vehicle and Charging Infrastructure. To Charge These Vehicle we need more power and Separate Power Infrastructure to ensure Stable and Clean Power System with support 24X7 only possible with addition Solar PV Power Plant and High Energy Storage Power System adoption and Implements where demand is more that 1MW.
Our Broad Band and Telecom Signal should be Strong Signal and Fast response as and when require by System.
Ministry Of Urban Infra , Railways, Power , National Highway and Road Infra already advise all State and Central to offer Charging Facilities as per demand in the Market 3KM Radius Public Charging and 25KM Both side of Highways Electric Vehicle Charging Station for Charging 2/3/4 Wheeler Vehicle along with Passenger Buses and Heavy Fleet Electric Vehicles.
This Can be Charging Station or with Restaurant in Highways power demand may be 2.00MW-4.00MW .
Plz Find Attach latest presentation EV Charging Infra from Linkvue System Pvt Ltd Kindly go through .visit www.linkvuesystem.com
We are into Manufacturing , Supply ,Design ,Engineering ,Selection of Genuine and Right Products with supervision support for Installation .
Electrical Safety Earthing ,Lightning and Surge Protection
Net Working Solution LAN ,Fiber ,Wireless and GSM Solutions
Automation and Data Logger RTU's
Protocol Convertor and FO Convertors
CCTV .Fire Alarm ,Access Controls, Security Systems
Fencing PIDS
Industrial PLUG Socket IP 68 Out door up to 400 Amps
Electric Vehicle Charging Connectors and Harness
Solar MC4 Connectors with and Without Fuses
Plz Contact M-9811247237 Mahesh Chandra Manav
manav.chandra@linkvuesystem.com.
Electric Vehicle Charging Stations for Commercial Real Estate ProfessionalsSemaConnect
SemaConnect is the leading provider of electric vehicle amenities to the North American commercial and residential property market. Learn about the new mass market electric vehicle industry, the benefits of installing an EV charging station at commercial properties, installation considerations and EV charging station incentive programs.
Now India is Implementing with Preference and Priority A Green Carbon Free Silent Road Transportation Electric Vehicle and Charging Infrastructure. To Charge These Vehicle we need more power and Separate Power Infrastructure to ensure Stable and Clean Power System with support 24X7 only possible with addition Solar PV Power Plant and High Energy Storage Power System adoption and Implements where demand is more that 1MW.
Our Broad Band and Telecom Signal should be Strong Signal and Fast response as and when require by System.
Ministry Of Urban Infra , Railways, Power , National Highway and Road Infra already advise all State and Central to offer Charging Facilities as per demand in the Market 3KM Radius Public Charging and 25KM Both side of Highways Electric Vehicle Charging Station for Charging 2/3/4 Wheeler Vehicle along with Passenger Buses and Heavy Fleet Electric Vehicles.
This Can be Charging Station or with Restaurant in Highways power demand may be 2.00MW-4.00MW .
Plz Find Attach latest presentation EV Charging Infra from Linkvue System Pvt Ltd Kindly go through .visit www.linkvuesystem.com
We are into Manufacturing , Supply ,Design ,Engineering ,Selection of Genuine and Right Products with supervision support for Installation .
Electrical Safety Earthing ,Lightning and Surge Protection
Net Working Solution LAN ,Fiber ,Wireless and GSM Solutions
Automation and Data Logger RTU's
Protocol Convertor and FO Convertors
CCTV .Fire Alarm ,Access Controls, Security Systems
Fencing PIDS
Industrial PLUG Socket IP 68 Out door up to 400 Amps
Electric Vehicle Charging Connectors and Harness
Solar MC4 Connectors with and Without Fuses
Plz Contact M-9811247237 Mahesh Chandra Manav
manav.chandra@linkvuesystem.com.
Electric Vehicle Charging Stations for Commercial Real Estate ProfessionalsSemaConnect
SemaConnect is the leading provider of electric vehicle amenities to the North American commercial and residential property market. Learn about the new mass market electric vehicle industry, the benefits of installing an EV charging station at commercial properties, installation considerations and EV charging station incentive programs.
Electric vehicle-new 2018 charging presentation mahesh chandra manav by c&sMahesh Chandra Manav
Presentation on EV Vehcile and Public EV Charging Station , Solar PV Power Project with High Energy Storage Battery Systems ,Electrical Contractor , EPC Companies ,EESL/BHEL/NTPC/CEA/Ministry Of Power ,State Dept Of Road Transport/Municipal Corporation ,Smart City,Power Distribution Companies,IOCL,HPCL,BPCL,Indraprast Gas Ltd Project by Mahesh Chandra Manav GM BD C&S M-9811247237 mahesh.manav@cselectric.co.in
Today transportation sector has facing many problems with conventional vehicles like petroleum and diesel vehicles which release most of the pollutants like CO2 and nitrogen oxide emissions which ultimately have an effect on human health. so to decrease this problem there is the invention of electrical vehicles but to fixed battery EVS the owner of the vehicle should wait for long hours to charge one vehicle and if the vehicle stops in any remote areas then it is difficult to charge the battery. So to reduce this problem and to increase electrical vehicle using the solution is to use autonomous battery swapping stations and producing mobile van technology for charging the vehicle in remote areas this idea ultimately increases EV adoption in the world which leads to having good human health.
India Great Initiates for Using Carbon Free Moving Transportation Systems and Direction to all state Govt plan for implementation .
EESL/Nit Ayog/DHI/BHEL/ARAI/ Central & State Smart City ,Municipal Corporation ,Power Distribution Companies and MNC Companies Intrestested as RESCO MODEL
Pulbished on www.youtube.com/pratinii.
Interesting basics of EVs which will satiate our curiosity about them and help us take informed decisions on owning an EV.
Electric Vehicle
Benefits of Electric Vehicle
What is Happening in the world of Electric Vehicle?
Electric Vehicle Charging Types
Wireless Charging
Advantages of Wireless Charging
Dynamic Wireless Charging
Impact of Wireless Charging on the Electric Vehicle Growth
References
EV Charging Infrastructure: Littelfuse Solutions to Enhance Safety, Efficienc...Littelfuse
Discover the wide range of Littelfuse EV charging infrastructure solutions in our automotive electronics portfolio, including silicon carbide (SiC) devices.
India Electric Vehicle Market 2018 2025: Report SampleANS MarketPro
India Electric Vehicle Market 2018-2025: Analytics, Value Chain, Strategy, Investment and Competitor Mapping, By Type of EV Technology (BEV, PHEV), By Type of Vehicle (Passenger Cars, Two-Wheelers, Three-Wheelers, Commercial Vehicles), By Charging Infrastructure (Normal Charging and High-Power Charging), By End-user (Individuals, Commercial Enterprises and Government) and Geography
These slides use concepts from my (Jeff Funk) course entitled Biz Models for Hi-Tech Products to analyze the business model for wireless charging for electric vehicles. Wireless charging eliminates cables that require time-consuming connections and maintenance as water and sun degrade them. Continuous wireless charging reduces the required batter capacity through coils that are included in vehicles and embedded in roads. These slides describe the specific value proposition for cities, building owners, and other specific customers and other aspects of the business model such as the method of value capture, scope of activities, and method of strategic control.
E-mobility | Part 4 - EV charging and the next frontier (English)Vertex Holdings
For the mass adoption of electric vehicle (EV) to become a reality, EV charging infrastructure must be made accessible, quick and reliable. Current signs indicate the sector is moving in the right direction – with China, Europe, US and Japan accelerating their charging infrastructure rollout plans, and notable charging network operators (i.e. ChargePoint, EVgo and Tritium) making billion-dollar exits.
Read more: https://bit.ly/3E8u4SL
Sensors In Automobiles - Information is collected from various sources including Wikipedia,and others.The file above may be a edited or modified version of an already uploaded file on the internet such as on any other website or so.
Electric vehicle-new 2018 charging presentation mahesh chandra manav by c&sMahesh Chandra Manav
Presentation on EV Vehcile and Public EV Charging Station , Solar PV Power Project with High Energy Storage Battery Systems ,Electrical Contractor , EPC Companies ,EESL/BHEL/NTPC/CEA/Ministry Of Power ,State Dept Of Road Transport/Municipal Corporation ,Smart City,Power Distribution Companies,IOCL,HPCL,BPCL,Indraprast Gas Ltd Project by Mahesh Chandra Manav GM BD C&S M-9811247237 mahesh.manav@cselectric.co.in
Today transportation sector has facing many problems with conventional vehicles like petroleum and diesel vehicles which release most of the pollutants like CO2 and nitrogen oxide emissions which ultimately have an effect on human health. so to decrease this problem there is the invention of electrical vehicles but to fixed battery EVS the owner of the vehicle should wait for long hours to charge one vehicle and if the vehicle stops in any remote areas then it is difficult to charge the battery. So to reduce this problem and to increase electrical vehicle using the solution is to use autonomous battery swapping stations and producing mobile van technology for charging the vehicle in remote areas this idea ultimately increases EV adoption in the world which leads to having good human health.
India Great Initiates for Using Carbon Free Moving Transportation Systems and Direction to all state Govt plan for implementation .
EESL/Nit Ayog/DHI/BHEL/ARAI/ Central & State Smart City ,Municipal Corporation ,Power Distribution Companies and MNC Companies Intrestested as RESCO MODEL
Pulbished on www.youtube.com/pratinii.
Interesting basics of EVs which will satiate our curiosity about them and help us take informed decisions on owning an EV.
Electric Vehicle
Benefits of Electric Vehicle
What is Happening in the world of Electric Vehicle?
Electric Vehicle Charging Types
Wireless Charging
Advantages of Wireless Charging
Dynamic Wireless Charging
Impact of Wireless Charging on the Electric Vehicle Growth
References
EV Charging Infrastructure: Littelfuse Solutions to Enhance Safety, Efficienc...Littelfuse
Discover the wide range of Littelfuse EV charging infrastructure solutions in our automotive electronics portfolio, including silicon carbide (SiC) devices.
India Electric Vehicle Market 2018 2025: Report SampleANS MarketPro
India Electric Vehicle Market 2018-2025: Analytics, Value Chain, Strategy, Investment and Competitor Mapping, By Type of EV Technology (BEV, PHEV), By Type of Vehicle (Passenger Cars, Two-Wheelers, Three-Wheelers, Commercial Vehicles), By Charging Infrastructure (Normal Charging and High-Power Charging), By End-user (Individuals, Commercial Enterprises and Government) and Geography
These slides use concepts from my (Jeff Funk) course entitled Biz Models for Hi-Tech Products to analyze the business model for wireless charging for electric vehicles. Wireless charging eliminates cables that require time-consuming connections and maintenance as water and sun degrade them. Continuous wireless charging reduces the required batter capacity through coils that are included in vehicles and embedded in roads. These slides describe the specific value proposition for cities, building owners, and other specific customers and other aspects of the business model such as the method of value capture, scope of activities, and method of strategic control.
E-mobility | Part 4 - EV charging and the next frontier (English)Vertex Holdings
For the mass adoption of electric vehicle (EV) to become a reality, EV charging infrastructure must be made accessible, quick and reliable. Current signs indicate the sector is moving in the right direction – with China, Europe, US and Japan accelerating their charging infrastructure rollout plans, and notable charging network operators (i.e. ChargePoint, EVgo and Tritium) making billion-dollar exits.
Read more: https://bit.ly/3E8u4SL
Sensors In Automobiles - Information is collected from various sources including Wikipedia,and others.The file above may be a edited or modified version of an already uploaded file on the internet such as on any other website or so.
Electric vehicle (EV) charging station powered by the scattered energy sources with DC Nanogrid (NG) provides an option for uninterrupted charging. The NG powered by the renewable energy sources (RES) of photovoltaic (PV) and wind energy. When the excess power produced by the renewable energy stored in the local energy storage unit (ESU) utilized during shortage power from the renewable sources. During the overloading of NG and demand of energy in ESU; the mobile charging station (MCS) provides an uninterrupted charging. The MCS provides an option for battery swapping and vehicle to grid feasibility. The MCS required to monitor the state of charge (SOC) and state of health (SOH) of the battery. Monitoring of SOC and SOH related to the various battery parameters like voltage, current and temperature. A laboratory prototype is developed and tested the practical possibility of EV to NG and Internet of things (IoT) based monitoring of battery parameters.
Energy management strategy for photovoltaic powered hybrid energy storage sys...IJECEIAES
Nowadays, electric vehicles (EVs) using additional energy sources frequently deliver a safe ride without concern about the distance. The energy sources including a battery, an ultra-capacitor (UC), and a photovoltaic (PV) are considered in this research for driving the EV. Vehicles that only use battery-oriented technologies experience problems with charging and quick battery discharge. EVs are used with an ultracapacitor to decrease the quick discharge effects and increase the lifetime of the battery. Furthermore, bidirectional DC-DC converters are a type of power electronics device used to verify the smooth transfer of generated power from energy sources to the motor throughout various stages of the driving cycle. Therefore, this study proposes a perturb and observe (P&O) energy management control technique based on tuna swarm optimization (TSO). The suggested TSOP&O completely uses UC while regulating the battery because it lowers dynamic battery charging and discharging currents. Due to the aforementioned aspect, the suggested TSO-P&O increases battery life and demonstrates a very dependable, long range power source for an electric car. The TSO-P&O technique achieves the EVs by obtaining the maximum speed of 91.93 km/hr. with a quicker settling time of 4,930 ms when compared with the existing zero-fuel zero-emission (ZFZE) method.
Two tier energy compansation framework based on smart electric charging stationSandeshPatil99
Abstract: Traditional cars produce a lot of carbon dioxide (CO2) emissions that are ejected into the atmosphere, causes pollution and greenhouse gases today, electric vehicles (EVs) have received much attention as an alternative to traditional vehicles. The traditional vehicles are powered by internal combustion engines. The electric vehicle is developed because of the advancement in battery technology and motor efficiency. The secondary batteries are the main energy sources of the EV. Thus, energy management is the key factor in EV or Hybrid Electric Vehicles (HEV) design. Moreover, the charge capacity of the battery will influence the endurance of electric vehicles. The main challenge in the HEV is the charging time required for the batteries and insufficiency of charging stations (CS) and therefore charging within existing distribution system infrastructure is problematic. Up to now the HEV‟s CS is in the range of 100 km per charge due to the on-board energy which is needed to be optimized. The second challenge for the EV‟s is their battery capacity which ranges from 8.6KWh to 15.2KWh. The consequent disadvantage is that the charging time for above mentioned size, in a level 1 household charger (120V, 50Hz, 15-20A) is more than 15 hours. Due to these constraints, the vendor (EV charging station supplier) needs a convenient distribution system to cater to customer demand as well as maximize benefits. A special attention must be given to the charging station. In future, the number of electric vehicles will be increasing to a greater extent; these electric vehicles have to re-charge their battery in a place (i.e.) charging station, so there will be a growing need of public accessing charging stations. This will have a significant impact on the power systems like transformers, protection devices etc. With respect to the varying load, it will have an impact on the consumers and vendors due to the traffic at this station, waiting time for charging the vehicles will increase etc. Therefore both the consumer and vendor will get assistance from a communication system which shares useful data regarding the charging station, whether the charging slots are free, rate at which charging is done, cost per unit etc.
A Comprehensive Overview of Electric Vehicle Charging using Renewable EnergyIAES-IJPEDS
The integration of PV with the electric vehicle (EV) charging system has been on the rise due to several factors, namely continuous reduction in the price of PV modules, rapid growth in EV and concern over the effects of greenhouse gases. Over the years, numerous papers have been published on EV charging using the standard utility (grid) electrical supply; however, there seems to be an absence of a comprehensive overview using PV as one of the components for the charger. With the growing interest in this topic, it is timely to review, summarize and update all the related works on PV charging, and to present it as a single reference. For the benefit of a wider audience, the paper also includes the bries description on EV charging stations, background of EV, as well as a brief description of PV systems. Some of the main features of battery management system (BMS) for EV battery are also presented. It is envisaged that the information gathered in this paper will be a valuable one–stop source of information for researchers working in this topic.
Implementation of Dynamic Performance Analysis of Electric Vehicular Technologyijtsrd
The choice of this paper is to enhance the reader widespread operational traits with various kinds of batteries, the charge and discharge dynamics of the battery version with six battery sorts, an upgrade and smooth to use battery dynamic model. Comparison among the six sorts of batteries, diverse parameters of the battery and Simulation results deliver the only of a type load situations of the Li Ion battery. The proposed assessment is completed to turn out to be privy to the immoderate overall performance of Li Ion battery evaluate to 6 batteries and its far studies for future paintings of the researchers. This paper introduces a comprehensive analysis of the dynamic overall performance of an electric vehicle system using one in all a kind manipulate algorithms. The whole mathematical models of the electric vehicle and its motor force device are defined in a scientific manner. Furthermore, the vehicle dynamics are tested with several control topologies to investigate the maximum suitable one. Konanki Srinivasa Rao | Inampudi Anil Babu | Mondru Chiranjeevi "Implementation of Dynamic Performance Analysis of Electric Vehicular Technology" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-6 | Issue-3 , April 2022, URL: https://www.ijtsrd.com/papers/ijtsrd49718.pdf Paper URL: https://www.ijtsrd.com/engineering/electrical-engineering/49718/implementation-of-dynamic-performance-analysis-of-electric-vehicular-technology/konanki-srinivasa-rao
electrical vehicle here described on the types of EV i.e. PHEV AND FCEV.An electric vehicle (EV) is a vehicle that is powered by electricity. EVs are either partially or fully powered by electricity. They use an electric motor powered by electricity from batteries or a fuel cell.
Some types of electric vehicles include:
Electric passenger cars
Electric buses
Electric trucks
Electric buggy
Electric tricycles
Electric bicycles
Electric motorcycles/scooters .
EVs have low running costs and are environmentally friendly. They have less moving parts for maintaining and use little or no fossil fuels. All-electric vehicles produce zero direct emissions. FCEVs use a propulsion system similar to that of electric vehicles, where energy stored as hydrogen is converted to electricity by the fuel cell. Unlike conventional internal combustion engine vehicles, these vehicles produce no harmful tailpipe emissions.Plug-in hybrid electric vehicles (PHEVs) use batteries to power an electric motor and another fuel, such as gasoline, to power an internal combustion engine (ICE).Plug-in-hybrid-electric vehicles (PHEVs) are the bridge between traditional gasoline vehicles and strictly battery-powered electrics. In many cases, the PHEV model serves as the performance trim. See, for example, the 302-hp Toyota RAV4 Prime or the 5.0-second-to-60-mph Lincoln Aviator Grand Touring.Like all-electric vehicles, fuel cell electric vehicles (FCEVs) use electricity to power an electric motor. In contrast to other electric vehicles, FCEVs produce electricity using a fuel cell powered by hydrogen, rather than drawing electricity from only a battery.Why is FCEV better?
Fuel cell vehicles are more efficient than combustion engines – a typical FCEV has about a 300 mile range. Similar to electric vehicles and hybrid technologies, their regenerative braking system is capable of capturing energy lost during braking and storing it in the battery.Battery Electric Vehicles (BEV) rely solely on a battery to power the car. Plug-In Hybrid Electric Vehicles (PHEV) have both batteries and an internal combustion engine (ICE) that work together or separately to power the car. Fuel Cell Electric Vehicles (FCEV) produce power from a hydrogen fuel cell in the car. PHEV (Plug-in Hybrid Electric Vehicle)
They are similar to HEVs but have a bigger battery pack and electric motor.
Read more about these types of EVs in the following sections.
1. Battery Electric Vehicle (BEV)
Vehicles powered solely by one or more electric batteries are known as BEVs. They are more popularly called EVs. Chargeable batteries power them, and there is no IC engine (petrol or diesel-powered). All the power comes from the battery pack, which is chargeable from the electricity grid. The charged battery pack sends power to one or more electric motors to move the vehicle.
Components of BEV
Battery pack
Electric motor(s).PHEVs are an extended form of HEVs. They have an internal combustion engine and an electric motor. However
The energy consumption of electric vehicles (EVs)depends on traffic environment, terrain, resistive forces acting on vehicle, vehicle characteristics and driving habits of driver. The battery pack in EV is the main energy storage element and the energy capacity determines the range of vehicle. This paper discusses the behavior of battery when EV is subjected to different driving environments such as urban and highway. The battery rating is selected based on requirement of driving cycle. The MATLAB/Simulink model of battery energy storage system (BESS) consisting of battery, bidirectional DC/DCconverter and electric propulsion system is built. The simulation is carried out and the performance of BESS is tested for standard driving cycles which emulate actual driving situations. It has been shown that, the amount of the energy recovered by battery during deceleration depends on the amount of regenerative energy available in the driving cycle. If the battery recovers more energy during deceleration, the effective energy consumed by it reduces and the range of the vehicle increases.
Evaluation of lightweight battery management system with field test of elect...IJECEIAES
A battery management system is a crucial part of a battery-powered electric vehicle, which functions as a monitoring system, state estimation, and protection for the vehicle. Among these functions, the state estimation, i.e., state of charge and remaining battery life estimation, is widely researched in order to find an accuracy estimation methodology. Most of the recent researches are based on the study of the battery cell level and the complex algorithm. In practice, there is a statement that the method should be simple and robust. Therefore, this research work is focused on the study of lightweight methodology for state estimation based on the battery pack. The discrete Coulomb counting method and the data-driven approach, based on the Palmgren-Miner method, are proposed for the estimation of the state of charge and remaining battery life, respectively. The proposed methods are evaluated through a battery-powered electric bus under real scenario-based circumstances in the campus transit system. In addition, the battery life-cycle cost analysis is also investigated. The tested bus has currently been in operation in the transit system for more than one year.
In this presentation, we have discussed a very important feature of BMW X5 cars… the Comfort Access. Things that can significantly limit its functionality. And things that you can try to restore the functionality of such a convenient feature of your vehicle.
𝘼𝙣𝙩𝙞𝙦𝙪𝙚 𝙋𝙡𝙖𝙨𝙩𝙞𝙘 𝙏𝙧𝙖𝙙𝙚𝙧𝙨 𝙞𝙨 𝙫𝙚𝙧𝙮 𝙛𝙖𝙢𝙤𝙪𝙨 𝙛𝙤𝙧 𝙢𝙖𝙣𝙪𝙛𝙖𝙘𝙩𝙪𝙧𝙞𝙣𝙜 𝙩𝙝𝙚𝙞𝙧 𝙥𝙧𝙤𝙙𝙪𝙘𝙩𝙨. 𝙒𝙚 𝙝𝙖𝙫𝙚 𝙖𝙡𝙡 𝙩𝙝𝙚 𝙥𝙡𝙖𝙨𝙩𝙞𝙘 𝙜𝙧𝙖𝙣𝙪𝙡𝙚𝙨 𝙪𝙨𝙚𝙙 𝙞𝙣 𝙖𝙪𝙩𝙤𝙢𝙤𝙩𝙞𝙫𝙚 𝙖𝙣𝙙 𝙖𝙪𝙩𝙤 𝙥𝙖𝙧𝙩𝙨 𝙖𝙣𝙙 𝙖𝙡𝙡 𝙩𝙝𝙚 𝙛𝙖𝙢𝙤𝙪𝙨 𝙘𝙤𝙢𝙥𝙖𝙣𝙞𝙚𝙨 𝙗𝙪𝙮 𝙩𝙝𝙚 𝙜𝙧𝙖𝙣𝙪𝙡𝙚𝙨 𝙛𝙧𝙤𝙢 𝙪𝙨.
Over the 10 years, we have gained a strong foothold in the market due to our range's high quality, competitive prices, and time-lined delivery schedules.
Things to remember while upgrading the brakes of your carjennifermiller8137
Upgrading the brakes of your car? Keep these things in mind before doing so. Additionally, start using an OBD 2 GPS tracker so that you never miss a vehicle maintenance appointment. On top of this, a car GPS tracker will also let you master good driving habits that will let you increase the operational life of your car’s brakes.
Ever been troubled by the blinking sign and didn’t know what to do?
Here’s a handy guide to dashboard symbols so that you’ll never be confused again!
Save them for later and save the trouble!
Why Is Your BMW X3 Hood Not Responding To Release CommandsDart Auto
Experiencing difficulty opening your BMW X3's hood? This guide explores potential issues like mechanical obstruction, hood release mechanism failure, electrical problems, and emergency release malfunctions. Troubleshooting tips include basic checks, clearing obstructions, applying pressure, and using the emergency release.
Symptoms like intermittent starting and key recognition errors signal potential problems with your Mercedes’ EIS. Use diagnostic steps like error code checks and spare key tests. Professional diagnosis and solutions like EIS replacement ensure safe driving. Consult a qualified technician for accurate diagnosis and repair.
What Exactly Is The Common Rail Direct Injection System & How Does It WorkMotor Cars International
Learn about Common Rail Direct Injection (CRDi) - the revolutionary technology that has made diesel engines more efficient. Explore its workings, advantages like enhanced fuel efficiency and increased power output, along with drawbacks such as complexity and higher initial cost. Compare CRDi with traditional diesel engines and discover why it's the preferred choice for modern engines.
5 Warning Signs Your BMW's Intelligent Battery Sensor Needs AttentionBertini's German Motors
IBS monitors and manages your BMW’s battery performance. If it malfunctions, you will have to deal with an array of electrical issues in your vehicle. Recognize warning signs like dimming headlights, frequent battery replacements, and electrical malfunctions to address potential IBS issues promptly.
"Trans Failsafe Prog" on your BMW X5 indicates potential transmission issues requiring immediate action. This safety feature activates in response to abnormalities like low fluid levels, leaks, faulty sensors, electrical or mechanical failures, and overheating.
Core technology of Hyundai Motor Group's EV platform 'E-GMP'Hyundai Motor Group
What’s the force behind Hyundai Motor Group's EV performance and quality?
Maximized driving performance and quick charging time through high-density battery pack and fast charging technology and applicable to various vehicle types!
Discover more about Hyundai Motor Group’s EV platform ‘E-GMP’!
Fleet management these days is next to impossible without connected vehicle solutions. Why? Well, fleet trackers and accompanying connected vehicle management solutions tend to offer quite a few hard-to-ignore benefits to fleet managers and businesses alike. Let’s check them out!
Comprehensive program for Agricultural Finance, the Automotive Sector, and Empowerment . We will define the full scope and provide a detailed two-week plan for identifying strategic partners in each area within Limpopo, including target areas.:
1. Agricultural : Supporting Primary and Secondary Agriculture
• Scope: Provide support solutions to enhance agricultural productivity and sustainability.
• Target Areas: Polokwane, Tzaneen, Thohoyandou, Makhado, and Giyani.
2. Automotive Sector: Partnerships with Mechanics and Panel Beater Shops
• Scope: Develop collaborations with automotive service providers to improve service quality and business operations.
• Target Areas: Polokwane, Lephalale, Mokopane, Phalaborwa, and Bela-Bela.
3. Empowerment : Focusing on Women Empowerment
• Scope: Provide business support support and training to women-owned businesses, promoting economic inclusion.
• Target Areas: Polokwane, Thohoyandou, Musina, Burgersfort, and Louis Trichardt.
We will also prioritize Industrial Economic Zone areas and their priorities.
Sign up on https://profilesmes.online/welcome/
To be eligible:
1. You must have a registered business and operate in Limpopo
2. Generate revenue
3. Sectors : Agriculture ( primary and secondary) and Automative
Women and Youth are encouraged to apply even if you don't fall in those sectors.
1. energies
Article
A Mobile Battery Swapping Service for Electric
Vehicles Based on a Battery Swapping Van
Sujie Shao * ID
, Shaoyong Guo and Xuesong Qiu
State Key Laboratory of Networking and Switching Technology, Beijing University of Posts and
Telecommunications, Beijing 100876, China; syguo@bupt.edu.cn (S.G.); xsqiu@bupt.edu.cn (X.Q.)
* Correspondence: buptssj@bupt.edu.cn; Tel.: +86-010-6119-8098
Academic Editor: Hongyu Wu
Received: 20 August 2017; Accepted: 19 October 2017; Published: 20 October 2017
Abstract: This paper presents a novel approach for providing a mobile battery swapping service for
electric vehicles (EVs) that is provided by a mobile battery swapping van. This battery swapping
van can carry many fully charged batteries and drive up to an EV to swap a battery within a few
minutes. First, a reasonable EV battery swapping architecture based on a battery swapping van is
established in this paper. The function and role of each participant and the relationships between
each participant are determined, especially their changes compared with the battery charging service.
Second, the battery swapping service is described, including the service request priority and service
request queuing model. To provide the battery swapping service efficiently and effectively, the battery
swapping service request scheduling is analyzed well, and a minimum waiting time based on priority
and satisfaction scheduling strategy (MWT-PS) is proposed. Finally, the battery swapping service is
simulated, and the performance of MWT-PS is evaluated in simulation scenarios. The simulation
results show that this novel approach can be used as a reference for a future system that provides
reasonable and satisfying battery swapping service for EVs.
Keywords: electric vehicle; battery swapping; battery swapping van; request scheduling;
request priority
1. Introduction
In recent years, due to the increasingly significant shortage of non-renewable resources, such as
oil and coal, excessive consumption, and the consequent environment pollution, electric vehicles (EVs)
have gradually drawn people’s attention and become favored as a type of clean energy vehicle [1].
The key issue for the effective operation of EVs is energy replenishment. It is known that there are two
main ways to solve this problem: EV charging and battery swapping [2,3]. In general, EV charging
requires a long charging process. Thus far, due to policy and money constraints, the charging stations,
charging piles and other charging infrastructure are not widely deployed. The abovementioned
reasons make it probable that EV users will be forced to stop and wait, which results in waiting anxiety.
In addition, EV users trade-off between the remaining battery energy, the location distribution of
charging facilities and their travel plans, which easily results in range anxiety [4,5]. Therefore, more
researchers and EV operators are turning their attention to battery swapping [6–8]. Battery swapping
can provide a new fully charged battery, which does not require depleting the energy of the old battery.
Range anxiety is eased, and to some extent infinite mileage is obtained. Because battery swapping
only requires a few minutes, waiting anxiety is significantly eased.
However, before the benefit of battery swapping becomes a reality, two problems need to be solved.
One is the EV battery technology, which is fundamental for battery swapping. A standardized EV
battery with the characteristic of high mileage, high energy density, high recycling ratio, high recovery
Energies 2017, 10, 1667; doi:10.3390/en10101667 www.mdpi.com/journal/energies
2. Energies 2017, 10, 1667 2 of 21
ratio, environmentally friendly ability and security needs to be developed [9]. Currently, the
development of zinc air batteries and zinc nickel batteries can initially meet the abovementioned
demand [10]. Therefore, the EV battery technology is not discussed in this paper. The other problem is
a reasonable and effective EV battery swapping architecture that can support the effective operation of
EV battery swapping.
The current EV battery swapping systems and infrastructure are mainly based on battery
swapping stations and battery charging factories. A larger number of batteries are centrally-charged
and transported to different battery swapping stations via a logistics system [11]. Most research is this
area is focused on the following issues: battery logistics strategy, battery swapping station planning
and construction strategy, and battery charging strategy for the battery swapping stations [12,13].
The abovementioned research intends to improve the coverage and service of a battery swapping
system. However, these approaches do not realize the objective of “get energy replenishment anytime
and anywhere.” EV users must drive to a battery swapping station for battery swapping. Due to the
obvious constraints of location and number of the existing battery swapping stations, there may still
be a queueing and waiting phenomenon [14]. Therefore, a more reasonable and effective EV battery
swapping architecture is needed.
To solve this problem, one effective idea is to switch from the existing passive battery swapping
mode to the active battery swapping mode. Recently, a new fast EV battery swapping device has been
developed. The patents [15,16] indicate that this device can be installed on a van, which transforms
the van into a mobile EV battery swapping station. This device has the advantages of accurate
positioning and convenient swapping due to its components, such as a positioning pin, positioning
hole, positioning track, positioning slot and PLC control system. The operations of removing and
installing a battery occur at the same time. Thus, the entire battery swapping process is very fast and
lasts only a few minutes (in the experimental environment, it is approximately 3 min). EVs drive into
the interior predetermined position of the battery swapping van through the folding slope steel plate to
perform an automatic battery swap. Thus, the actual transaction of battery swapping occurs inside the
battery swapping van. The mobility of the battery swapping van removes the constraints of location
and quantity of EV battery swapping stations. The battery swapping locations are more flexible.
When the EV cannot drive due to energy depletion, the battery swapping location is undoubtedly
generated based on the EV’s location. Otherwise, the battery swapping location can be generated
based on the specific battery swapping service scheduling strategy or the driver’s actual requirements.
Using the battery swapping van, the active battery swapping can be achieved anytime and anywhere.
The battery swapping van will provide a fast, convenient, and flexible battery swapping service, and it
will ease the pressure of battery logistic system. Based on a battery swapping van, we mainly study
the following problem in this paper:
• EV battery swapping architecture based on a battery swapping van For the effective and efficient
operation of an EV battery swapping service based on a battery swapping van, a reasonable EV
battery swapping architecture needs to solve the specific process of battery production, charging,
transportation, storage, swapping, communication and others and identify the specific functions
of each participant of the entire EV battery swapping system and the relationship between them.
Moreover, profit mode and some details and practical factors should be discussed. Thus, our first
contribution is to establish an EV battery swapping architecture based on a battery swapping van.
• Battery swapping service request scheduling There are clear battery energy differences between
the battery swapping requests of different EV users. Furthermore, the locations of the moving battery
swapping van and EVs vary, which leads to the consequent change of battery energy consumption.
Therefore, to improve the efficiency and effectiveness of battery swapping service, battery swapping
requests need to be distinguished and scheduled based on the advanced management system.
Our second contribution is to propose a minimum waiting time based on priority and satisfaction
3. Energies 2017, 10, 1667 3 of 21
scheduling strategy (MWT-PS) to distinguish and schedule the battery swapping requests. First, we
define the battery swapping service request and set its priority according to the State of Charge (SOC).
Second, we establish a battery swapping service request queuing model according to the specific
battery swapping service mode based on a battery swapping van. Then, we discuss the satisfaction of
EV users based on waiting time and request priority and establish the scheduling model. Finally, the
MWT-PS is proposed based on the abovementioned analysis.
The rest of this paper is organized as follows: in Section 2, a related work is introduced.
In Section 3, the EV battery swapping architecture based on a battery swapping van is established.
The battery swapping service request is discussed in Section 4. In Section 5, the battery swapping
request scheduling mechanism MWT-PS is proposed. Simulation results are analyzed in Section 6.
Section 7 draws the conclusion.
2. Related Work
Currently, the body of work related to EVs is rapidly increasing. For the realization of EVs, many
studies have looked at the potential impact, adoption limitation, potential operational pattern and
actual usage simulation of EVs in current electricity grids [17–20]. Most research indicates that energy
replenishment is a significant factor in making EVs more competitive because of range anxiety among
the EV users [4,5].
To help alleviate concerns of range anxiety among the EV users, many effective methods of energy
replenishment are analyzed, including location sites of energy replenishment stations, how many
stations to construct, energy replenishment strategies, and so on. For both the maximal coverage
and minimal costs, the siting of charging stations is analyzed using a case study of Penghu in
Taiwan [21]. An ordered EV charging strategy in a charging station to improve charging effectiveness
is proposed [22]. The stochastic programming model, which takes into account price variation and the
stochastic behavior of vehicle staying patterns, is put forward to achieve the optimal management of
EV charging points [23]. A previous study [24] has proposed an integrated EV charging navigation
framework that takes into consideration the impact of both the energy and transportation systems to
save time of EV users and provide effective charging. A heuristic charging strategy is proposed to
improve the real-time charging performance by optimizing the charging rate feasible searching region
and saving searching time [25].
In addition to energy replenishment methods that are based on battery charging, the methods
that are based on battery swapping have been widely studied. A vehicle flow-interception model is
proposed, and the optimal number of battery swapping stations, which included retrofitting of the
existing petrol station, is analyzed and specifically evaluates a case study in Alexandria (VA, USA) [26].
Reference [27] presents an integer programming model to determine the location strategy of battery
swapping stations and the routing plan of a fleet of EVs that are under a battery driving range
limitation. The optimal placement and sizing of the battery swapping stations are studied using the
Artificial Bee Colony algorithm [6]. The EV battery swapping station strategy model is proposed that
considers frequency and distribution of EV users’ arrivals, cooperation of users, and grid load demand
curves [28]. References [29,30], respectively, studied a service and operation scheduling model and an
economic scheduling model for EV battery swapping stations to succeed in the rolling out of EVs.
All the abovementioned studies assume that EVs conduct most of their energy replenishment at
static location energy replenishment stations. However, in practical implementations, mobile energy
replenishment options would need to be provided to minimize response times and key indicators,
such as latencies and miss ratios, and further help alleviate concerns of range anxiety. Reference [31]
proposed a mobile charging platform as an alternative implementation of those static battery recharge
options, the implementation could either be in the form of a mobile plug-in charger or a mobile
battery-swapping station. The mobile energy replenishment system possesses similar properties to
mobile service systems such as ambulance and mobile data collection in WSN. The key factors are
usually the location of mobile servers, coverage areas, service queuing models, and so on.
4. Energies 2017, 10, 1667 4 of 21
There are many previous studies about such mobile service systems. References [32–34] determined
that the location of ambulance bases and coverage areas are usually the key parameters. The reasonable
and accurate queuing models of mobile servers are well studied through the analysis of mobile data
collection in WSN with mobile data collectors. The most fundamental service queueing discipline of
first-come–first-serve (FCFS) is explored in [35,36]. The nearest-job-next (NJN) discipline is explored
in [37]. It is clear that battery swapping vans in our EV battery swapping service system can be viewed
as a special type of mobile servers. Therefore, we can adopt a similar approach based on a queue
theory to analyze the mobile battery swapping process for EVs.
3. EV Battery Swapping Architecture Based on Battery Swapping Van
In this section, a reasonable EV battery swapping architecture is established, which determines
three basic issues about how to realize the EV battery swapping service based on a battery swapping
van. The first issue is the battery swapping system structure, which should clearly note the main
participants of the entire system, identify their functions and roles, and clarify their relationship and
communications. The second issue is the economic analysis that consists of profit mode and cost
analysis. We mainly analyze the profit source, primary system cost and the cost for EV users. The last
issue is the practical factors, which mainly focuses on the realization of battery swapping service based
on a battery swapping van such as funds and policies of government agencies, environmental impact
of battery swapping van, and so on.
3.1. Battery Swapping System Structure
The application of a battery swapping van brings a clear change to the EV battery swapping.
The specific functions of each participant and the roles they played will be consequently changed.
To reduce the impact of these changes and provide an effective and efficient EV battery swapping
service, the function and role of each participant are determined, especially their changes. The specific
process of battery production, charging, transportation, storage and swapping, and communication
are described. The relationship between each participant, as shown in Figure 1, is then discussed.
Energies 2017, 10, 1667 4 of 21
of mobile data collection in WSN with mobile data collectors. The most fundamental service queueing
discipline of first-come–first-serve (FCFS) is explored in [35,36]. The nearest-job-next (NJN) discipline
is explored in [37]. It is clear that battery swapping vans in our EV battery swapping service system
can be viewed as a special type of mobile servers. Therefore, we can adopt a similar approach based
on a queue theory to analyze the mobile battery swapping process for EVs.
3. EV Battery Swapping Architecture Based on Battery Swapping Van
In this section, a reasonable EV battery swapping architecture is established, which determines
three basic issues about how to realize the EV battery swapping service based on a battery swapping
van. The first issue is the battery swapping system structure, which should clearly note the main
participants of the entire system, identify their functions and roles, and clarify their relationship and
communications. The second issue is the economic analysis that consists of profit mode and cost
analysis. We mainly analyze the profit source, primary system cost and the cost for EV users. The last
issue is the practical factors, which mainly focuses on the realization of battery swapping service
based on a battery swapping van such as funds and policies of government agencies, environmental
impact of battery swapping van, and so on.
3.1. Battery Swapping System Structure
The application of a battery swapping van brings a clear change to the EV battery swapping.
The specific functions of each participant and the roles they played will be consequently changed. To
reduce the impact of these changes and provide an effective and efficient EV battery swapping
service, the function and role of each participant are determined, especially their changes. The specific
process of battery production, charging, transportation, storage and swapping, and communication
are described. The relationship between each participant, as shown in Figure 1, is then discussed.
Figure 1. EV battery swapping structure based on battery swapping van.
3.1.1. Battery Swapping Van
The current battery swapping service with a battery swapping station as its core, in essence, is a
passive service that needs to wait for users and swap their batteries. If the service does not satisfy the
need of EV users, they still suffer from range anxiety. However, the application of a battery swapping
van causes a fundamental change. When the number of battery swapping vans gets big enough, a
Figure 1. EV battery swapping structure based on battery swapping van.
5. Energies 2017, 10, 1667 5 of 21
3.1.1. Battery Swapping Van
The current battery swapping service with a battery swapping station as its core, in essence, is a
passive service that needs to wait for users and swap their batteries. If the service does not satisfy the
need of EV users, they still suffer from range anxiety. However, the application of a battery swapping
van causes a fundamental change. When the number of battery swapping vans gets big enough,
a battery can be sent to EV users anytime and anywhere. EV users can choose to stop to wait for a
battery swapping van or keep driving until the battery swapping van catches up with them. This will
appear as if EV users travel with an energy replenishment device, which will finally eliminate waiting
anxiety and range anxiety.
The battery swapping van is equipped with an automatic positioning system and a communication
system that can communicate with the battery swapping service management system and EV users via
wireless communication technology. With these information communication systems, the scheduling
results of battery swapping service requests are received, and the current information about the battery
swapping van, such as position, direction and battery storage, are sent to the battery swapping service
management system. In addition, the responses for battery swapping requests are sent to the EV users.
The battery swapping van usually replenishes its fully charged battery storage in the battery
swapping station. The timing of replenishment is determined by its fully charged battery storage,
amount of battery swapping requests and its distance to the battery swapping station. It can also get
its fully charged battery storage replenishment in the battery charging factory if the fully charged
battery storage of battery swapping station is not sufficient or the battery swapping van is free.
In general, one battery swapping van would have a limited carrying capacity of fully charged
batteries. It can only serve a fixed number of EVs before having to return to obtain fully charged
replenishments. Therefore, to reduce driving time and improve service efficiency of the battery
swapping van, the service area of one battery swapping van should not cover too many roads. The
entire district should be divided into some small service areas according to the different population
and road densities. One battery swapping van serves one service area that it patrols during its work
time. Moreover, to guarantee the satisfaction of EV users, the bordering area should be shared between
two adjacent service areas.
3.1.2. EV/EV Users
The existence of a battery swapping van allows EV users to completely get rid of the old “refueling”
mode. They do not have to look for a charging station or battery swapping station to get their energy
replenishment but simply call a battery swapping service anytime and anywhere. They just need to
send their SOC and information about speed, direction and position. Then, they will get fast and
accurate battery swapping service with a battery swapping van and have no need to consider how
much the SOC is. Even if we set the rule to specify that only the battery whose SOC is less than a
certain level can be swapped to prolong the service life of the battery, the commuter demands of EV
users still can be guaranteed. The mileage of EV seems to be significantly enhanced.
In this mode, there are two options for the EV users to swap their battery. One option is to swap
the battery using the battery swapping van. The other option is to swap the battery at the nearest
battery swapping station after judging that the remaining battery energy is sufficient to reach the
battery swapping station. The two options are complementary to each other. EV users no longer
need to worry about whether the existing battery energy is sufficient or whether there are enough
battery swapping stations on their traveling routes, and so on. Finally, the “want to go, then go” will
become true.
3.1.3. Battery Swapping Station
Generally, as a commuter tool, an EV is the main mode of daily transportation. An EV is used
to commute to work in the morning and go back home at night, with occasional uses for driving to
6. Energies 2017, 10, 1667 6 of 21
purchase a meal and other destinations during the day. During the peak commute hours, energy
consumption is relatively high, and consequently, the battery swapping demand is high. Thus, to
only replenish the fully charged battery storage using the battery logistics system may be not enough
because of the limited capacity of the fully charged battery storage in the battery swapping station.
To guarantee the battery replenishment and alleviate the transportation pressure of the battery logistics
system, an effective solution is to deploy a battery charging system at the battery swapping station.
This battery charging system is only used to charge the batteries that are swapped out and it is not
open to EV users. This not only improves the fully charged battery storage but also plays an important
role in balancing peak load in the smart grid.
At this point, the battery swapping station has two approaches for replenishing its battery storage:
from a battery charging factory with a battery logistics system and from its own battery charging
system. In addition, the battery swapping station has two main functions: to provide a battery
swapping service for the EV users directly and to replenish the fully charged batteries for the battery
swapping van to provide a battery swapping service for the EV users indirectly.
3.1.4. Battery Swapping Service Mobile APP
EV users receive the battery swapping information, which is published by the battery swapping
service management system, and send their real-time battery swapping request via the APP installed on
the smart mobile device [38]. Specifically, through the mobile APP, information about the distribution
of battery swapping stations, real-time battery swapping price, and real-time distribution of battery
swapping vans will be known. Additionally, the EV users can send their real-time position, SOC,
driving speed and direction, etc. to launch an accurate battery swapping request for obtaining fast and
accurate battery swapping service.
Using the real-time information exchange of the battery swapping service mobile APP, the accurate
real-time positions of EV users are automatically located with the mapping software, and EV users do
not need to worry about how to describe their location if they are unfamiliar with the area or if the
location is not accurately described. The time cost and risk caused by inaccurate users’ information are
eliminated. Moreover, the EV users can complete the payment, service evaluation and other operations
using the mobile APP.
3.1.5. Battery Swapping Service Management System
As the fundamental communication and management platform of battery swapping, the battery
swapping service management system offers a variety of battery swapping applications such as
battery swapping service reservation, battery swapping service customization, and so on. The battery
swapping service management system regularly releases real-time prices. The charge of one battery
swapping service is not constant but determined by both real-time price and real-time remaining
battery energy of an EV user.
After receiving the battery swapping request of an EV user, the battery swapping service
management system schedules the request according to the result of battery swapping request
scheduling and assigns the request to the corresponding battery swapping van. Therefore, the battery
swapping service management system should keep tracking the real-time position, driving direction
and fully charged battery storage of each battery swapping van. Then, the battery swapping service
management system sends the acknowledgement of the chosen battery swapping van to the battery
swapping service mobile APP in the EV user’s smart mobile device. Once this battery swapping task
is completed, the battery swapping service management system receives the completion messages
from both the battery swapping van and EV user, records and ends the battery swapping service.
3.1.6. Battery Charging Factory
Most EV batteries are centralized-charged in the battery charging factory and then sent to battery
swapping stations by the battery logistics system. Occasionally, some battery swapping vans can get
7. Energies 2017, 10, 1667 7 of 21
fully charged battery replenishment at the battery charging factory. The centralized charging process
needs a significant amount of electrical energy, thus, renewable energy resources are an ideal way to
share part of energy load to balance the peak energy load in a smart grid. In addition, from the battery
charging factory operators’ point of view, the deployment of renewable energy resources can save a
considerable cost of purchasing energy from the smart grid and increase the operation income because
they do not need to purchase energy from the smart grid if the energy provided by renewable energy
resources is sufficient.
3.1.7. EV and Battery Manufacturers
For the realization of EV battery swapping based on a battery swapping van, the most important
aspects for the EV and battery manufacturers are different from what currently exists. The goal is to
develop a set of standard battery production lines and battery installation devices to unify the battery
usage of different brand EVs. The reusability and commonality of a unified battery will provide people
an enhanced desire to have more than one EV, which results in good sales and finally promotes the
battery swapping service. Moreover, this will save battery cost and result in greater investment into the
design and transformation of EV patterns and performance, which will reduce the EV cost, makes EV
sufficient, and improve profit margins and sales. However, we must admit that this requires a relatively
long time to realize and, to some extent, depends on funds and policy support from the government.
The relationship between these seven main participants of the EV battery swapping architecture,
which is based on the battery swapping van concept, is shown in Figure 1. The EV and battery
manufacturers produce standard-sized batteries and supply them to the battery charging factory and
battery swapping stations through the battery logistics system. At the battery charging factory, a
battery is charged via the smart grid and renewable energy resources. However, the battery is only
charged via the smart grid at the battery swapping station. The battery swapping van generally obtains
the fully charged battery storage replenishment from a battery swapping station, and sometimes it can
also receive the fully charged battery storage replenishment from a battery charging factory. EV users
have two choices for swapping a battery. One option is to drive to the nearest battery swapping station.
The other option is to wait for the battery swapping van after the battery swapping request has been
sent. The battery swapping van and EV user exchange information with each other via the battery
swapping service mobile APP and management system. The EV user sends a battery swapping request
via the battery service mobile APP and receives a response message and a real-time price. The battery
swapping van follows the scheduling results of the battery swapping service management system to
provide the EV user an active battery swapping service.
3.2. Economic Analysis
3.2.1. Profit Mode
The major operators of a battery swapping service must invest in the battery charging factory,
renewable energy resources, a battery swapping service management system, a battery swapping
station, battery swapping vans, a battery logistics system, and an energy suply. The first three
investments are one-time investments. The last four investments depend on the number of battery
swapping service EV users, and can be referred to as dynamic investments. However, in these dynamic
investments, only the investment in energy clearly increases as the number of battery swapping service
EV users increases.
Moreover, some energy loss is unavoidable during the battery charging or discharging process.
Due to the battery formula, working temperature, resistance and other factors, energy conversion
efficiency cannot be completely 100%. Obviously, energy loss brings additional investment for the
major operators of a battery swapping service, and this part of investment also increases as the number
of battery swapping service EV users increases.
8. Energies 2017, 10, 1667 8 of 21
Their incomes mainly include the battery swapping service income, dividends from EV and
battery manufacturers, franchise fees for the battery swapping station and funds supported by the
government agencies. The latter is a one-time income, and the rest depend on the number of battery
swapping service EV users, which can be referred to as dynamic incomes. In these dynamic incomes,
only the battery swapping service income clearly increases as the number of battery swapping service
EV users increases.
Therefore, we can approximately calculate the profit of the battery swapping system that is
based on a battery swapping van using the formula (profit = service income − investment in
energy − investment in energy loss + an approximate fixed profit of other investments and incomes).
Then, we can conclude that the profit of battery swapping service is made of selling electrical energy
and not by selling cars or batteries.
For the battery swapping service, the service income is calculated as the current battery energy
consumption multiplied by a fixed price. This fixed price is set by operators according to their profit
expectation, which means that there is no extra cost for EV users once the fixed price is set. Thus, just
like oil prices, in most cases, the fixed price only increases as the electricity energy price purchasing
from the smart grid rises. The cost is increased by adding a large number of swapping vans, which may
not result in additional cost to the EV users. Moreover, the cost of EV users may decrease as the
number of battery swapping service EV users increases.
3.2.2. Cost Analysis
In the abovementioned analysis, EV users only pay money for the proposed mobile battery
swapping service according to the amount of energy that is necessary and the fixed price that is set by
operators. However, in the battery charging mode, EV users not only pay for the energy, but also pay a
service fee and a parking fee. Thus, compared with the battery charging mode, our proposed battery
swapping service has an obvious cost advantage for the EV user.
The State Grid Corporation of China clearly stipulates that the charging price for EVs must consist
of the basic electricity energy price and a service fee. Currently, the charging price is set as 1.2¥/kwh
in Beijing. Generally, it will take several hours for an EV to fully charge its battery. For example, it will
take about 6 h for a BYD-E6 vehicle (300 km, 57 kwh) to get its battery 80% charged with a charging
power of 7.5 kw. If the parking price is 8¥/h and the parking fee of the first hour is free, then the total
charging fee is about 94¥. The average charging fee of 1 kwh electricity energy is about 2.09¥. The fixed
price of our proposed mobile battery swapping service is close to the basic electricity energy price,
it mostly fluctuates between 0.6 and 1.0 in Beijing, so in principle the EV users will pay less for the
battery swapping service.
Table 1 shows the major indicators of several typical batteries. The power density and energy
density of the four types of batteries are not too different, however the zinc air battery and zinc
nickel battery are more suitable as swapping batteries for their higher service life and recycling rate,
and lower cost.
Table 1. Major indicators of typical batteries.
Indicators
Typical Batteries
Nickel Battery Lithium Battery Zinc Air Battery Zinc Nickel Battery
Power density (w/kg) 1300 2000 1000 2700
Energy density (wh/kg) 65–70 110–130 180–220 75–100
Cost (¥/wh) 4.2 9.0 0.6 1.8
Service life (times) 500–600 1500 3000 1600–2000
Recycling rate 5% 3% 90% 90%
For battery charging mode, the operators need to construct as many battery charging stations
as possible, and pay the maintenance fees of these battery charging stations. For our proposed
mobile battery swapping service, the operators need to acquire many battery swapping vans and a
9. Energies 2017, 10, 1667 9 of 21
battery logistics system. Next, we calculate the cost of the two modes using the data of the State Grid
Corporation of China.
If a battery charging station has 10 battery chargers, then the cost of infrastructure, the cost
of energy distribution and the cost of maintenance for one year (employees and devices) are about
2,400,000¥, 2,000,000¥, and 360,000¥, respectively. We can then calculate the cost of a battery charging
station as approximately 4,760,000¥. However, the cost of a battery swapping van and the cost of
maintenance for one year (employees and devices) are about 100,000¥ and 250,000¥, respectively.
The total cost of a battery swapping van is approximately 350,000¥. It may cost 5,000,000¥ to establish
a battery logistics system, but it can serve at least dozens of battery swapping stations. Thus, we can
conclude that the cost of a battery charging station is at least 10 times more than that of a battery
swapping van. Generally, 10 battery swapping vans are enough to meet the battery swapping service
requests in the similar coverage area as a battery charging station. Apparently, the operators must pay
less for the battery swapping service.
Nowadays, lots of EVs, such as the BJEV-E series (200–260 km, 41.4 kwh), Tesla Model S
(372–572 km, 85 kwh), and so on, support battery swapping mode. The Beijing Automotive Group
plans to construct 200 battery swapping stations in 2017. The State Grid Corporation of China has
turned its focus to the significant battery swapping requirements of bus groups and taxi companies
that always have a large number of the same type of EVs. With the investment of these big enterprises,
the battery swapping service market may be greatly promoted, and the costs for operators and EV
users may consequently get further decreased.
3.3. Practical Factors
3.3.1. Funds and Policies
The most influential factor when realizing the battery swapping systems that are based on mobile
battery swapping vans is the funds and policies. In today’s EV market, neither the battery charging
mode nor the battery swapping mode are dominant. It can be expected that most countries will
vigorously promote the wide application of EVs, which means a large amount of investment funds
and favorable policies will be needed. Once the battery swapping mode is selected, the infrastructure
construction, environment of battery swapping van and operation funds will be significantly promoted.
What is more important is the potential and immeasurable role in promoting the battery swapping
service market. The EV and battery manufacturers will invest more in battery R&D and EV
standardization and manufacture, which is more conducive to the development of battery swapping
services. Currently, there is a competition between battery swapping and charging. Only more
reasonable designs, more ideal prospects and more EV market share can seize the opportunity to
secure more funds and favorable policies. Thus, overcoming the current difficulties of funds and
policies and designing a reasonable battery swapping service and operation scheme to be recognized
by most EV users and industry participants are what we should do if committed to obtaining more
funds and policy support from the government.
3.3.2. Environmental Impact of Battery Swapping Vans
Theoretically, battery swapping vans are able to complete battery swapping requests for EVs at
any location. In today’s EV application environment, this actually may not be reasonable because of
parking or space restrictions, specifically in business districts. To solve this problem, there are two
main approaches except for constructing parking spaces by the battery swapping service operators
themselves, which is definitely costly and slow. There can be avenues for operators to negotiate
addresses for the major parking operators in the areas. This can produce some parking spaces for the
battery swapping van. The other avenue is to negotiate with the government agencies to obtain funds
and policy support. With the funds and policy support, many parking spaces can be constructed,
and some predetermined positions of the road will be opened for parking a battery swapping van. It can
10. Energies 2017, 10, 1667 10 of 21
be expected that more predetermined positions of the road, even entire roads, will be opened as long
as the battery swapping service that is based on a battery swapping van receives rapid development.
Due to the mobility of battery swapping vans and EVs, there are clear differences between
different battery swapping service requests. To effectively carry out the battery swapping service,
the battery swapping service requests are distinguished, and the battery swapping service is discussed
in the next section.
4. Battery Swapping Service
In this paper, an EV battery swapping service that is based on a battery swapping van is discussed.
When an EV user wants to use the battery swapping service, a battery swapping service request needs
to be sent to the battery swapping service management system. Then, the battery swapping service
management system assigns this request to one battery swapping van, which is in a working state in
its patrolling area. After the chosen battery swapping van confirms this request, it will drive to the EV
user and complete this battery swapping service.
4.1. Service Request Priority
Theoretically, EV users can launch a battery swapping service request anytime and anywhere no
matter how much the SOC is. However, this will increase the workload of the entire battery swapping
system as well as usage loss of batteries and devices if a battery with a relatively high SOC is swapped.
Moreover, there is no doubt that this will seize the opportunity of other EV users with an eager demand
for battery swapping. Therefore, it is recommended that EV users should launch the battery swapping
service request when the SOC is relatively low. Therefore, a battery swapping request should first
contain the information about SOC.
During one service period, the battery swapping van keeps moving, and EVs can stop to wait or
keep moving until they meet each other to save time. To provide an accurate battery swapping service
as soon as possible, real-time position, driving direction and speed of both the battery swapping van
and EV need to be exchanged. Thus, a battery swapping request should also contain this information.
We denote Uid(id = 1, 2, . . .) as the EV user with an ID id. The EV user Uid launches a battery
swapping service request Rid(t, SOC, pos, dir) via the battery swapping service mobile APP at time t.
We, respectively, denote pos, dir as the real-time position and driving direction at time t.
Due to the range anxiety, it is highly unlikely that EV users will launch a battery swapping
request when the battery energy is exhausted. When they consider that SOC is as low as possible
according to the mileage requirement, convenience, and other factors, they will choose to launch
the battery swapping request. However, different EV users launch their battery swapping request
with different SOCs. Therefore, to complete as many battery swapping services as possible before the
battery energy is exhausted, it is necessary to distinguish different battery swapping requests and
prioritize them. For EV users, the fundamental requirement is battery energy; thus, this parameter
used to prioritize the battery swapping requests according to SOC. In this paper, the method of
setting thresholds and dividing battery energy into several intervals is used. Table 2 shows the battery
swapping request priority.
Table 2. Battery swapping request priority.
Rid SOC ≤ 5% 5% < SOC ≤ 10% 10% < SOC ≤ 20% SOC > 20%
priority 1 2 3 4
Currently, the mileage of many EVs such as the BYD-E series (305 km), BJEV-E series (200–260 km),
and so on is approximately 200–300 km. The mileage of some EVs such as Tesla Model 3 (345 km),
Tesla Model S (372–572 km), and so on is beyond 300 km. Without loss of generality, we choose 300 km
as the mileage of EVs for the purpose of calculation in this paper. When the SOC is not greater than
11. Energies 2017, 10, 1667 11 of 21
5%, the EV can only drive for approximately ten kilometers or ten minutes at a speed of approximately
50 km/h. Thus, this type of battery swapping request should be responded to in a very short time and
has the highest priority. When the SOC is within 5%–10%, the battery energy will not be exhausted
immediately but within a relatively short time. This type of battery swapping request is reasonable and
should have the second priority. When the SOC is higher than 20%, the EV can drive for at least tens
of kilometers more. In most cases, this type of battery swapping request is not urgent and necessary.
The priority is obviously the lowest. Generally, it will not be responded to if the battery swapping
vans are busy. Moreover, if there is no convincing reason for launching the battery swapping request,
the EV user will be given some price penalty or credit penalty.
The priority of battery swapping request will change over time. After waiting for a period of
time, the priority of a battery swapping request may increase. The fully charged battery can support
driving s km, and the speed of EV is v km/h. Let SOCh be the SOC threshold of the higher priority.
Then, after time tp, the priority of the battery swapping request will increase to the priority that is
associated with SOCh:
tp = (SOC − SOCh)s/v (1)
For example, if the initial priority of battery swapping request is third, 10% < SOC ≤ 20%,
then after tp = (SOC − 10%)s/v time, the priority will be converted into second. Furthermore, after
the tp = (SOC − 5%)s/v time, the priority will be converted into the first. The conversion time of the
battery swapping request priority is shown in Table 3.
Table 3. Conversion time of the battery swapping request priority.
Current Priority
Next Priority
3 2 1
4 (SOC-20%)s/v (SOC-10%)s/v (SOC-5%)s/v
3 (SOC-10%)s/v (SOC-5%)s/v
2 (SOC-5%)s/v
The content authenticity of the battery swapping request needs to be confirmed. Generally, high
priority means that the battery swapping service will be provided to the requesting EV first. Thus, to
seek a relatively high priority, some people will on purpose falsely report a lower SOC than the true
values. In addition, some people will not cancel a battery swapping request immediately when they
changed their battery swapping plans or decided to stop the current travel plans. Thus, we established
the EV user’s credit model. Let Cid be the current credit of the EV user Uid. The credit calculation is
shown in Equation (2):
Cid =
(
Cid + βα, 0 < β ≤ 1, complete once battery swapping
Cid − α, else
(2)
where α is the positive constant, β is the positive decimal, Cid establishes the upper bound, and β
decreases as Cid increases, which means that credit is easily destroyed but difficult to be rebuilt.
4.2. Service Request Queuing Model
The general battery swapping process is easily translatable into a service process of the queuing
model, where the battery swapping service management system acts as the server, and the event of
the EV user requesting a battery swapping service is modeled as the client arrival. Once the EV has
completed a battery swap, the event is treated as a client departure.
From the previous analysis in Section 3, to improve the service efficiency and guarantee the EV
users’ satisfaction, the entire district will be divided into small service areas. Each service area has
battery swapping vans that patrol it. One battery swapping van only serves the requests that belongs
to its patrolling area. Therefore, each service area should have its own battery swapping service queue.
12. Energies 2017, 10, 1667 12 of 21
Moreover, the service area that one battery swapping request belongs to would change over time
because of the mobility of EVs. When the EV drives out of one service area, its battery swapping request
should be queued in the battery swapping service queue of the adjacent service area. The general
battery swapping service queuing model is shown in Figure 2.
Energies 2017, 10, 1667 12 of 21
Figure 2. The general battery swapping service request queuing model.
In the battery swapping scenario, the utilization of individual EVs is normally independent from
each other, which indicates that their battery swapping requests are launched independently.
Therefore, for each single service area, the battery swapping service queuing model is the same. In
this paper, we base our analysis on a single service area. The general battery swapping service
queuing model for a single service area is shown in Figure 3.
Figure 3. General queuing model for a single service area.
Based on this general battery swapping service queuing model for a single service area, there
are several submodules that need to be specified to determine a representative model.
4.2.1. Request Arrival
The request arrival determines the number and frequency of the battery swapping request. For
a single service area, the request arrival consists of two parts: the request launched in this area and
the request transferred from the adjacent service area. Both of them are independent of each other.
Commonly, we can assume a Poisson process to capture the request arrival.
4.2.2. Request Queuing Discipline
The request queuing discipline determines the order by which the requesting EVs will be served.
It would refer to the next EV to swap its battery. The disciplines can include HPF (select the request
with the highest priority first), FCFS (queuing requests according to the order of their request times),
NJN (select the request that is spatially closest to the current position of the battery swapping van
first), STDF (select the request that is the same driving direction to the battery swapping van first if
the requesting EV is in a parked state), HCF (select the request with the highest credit first), etc.
The SOC is a fundamental factor for battery swapping. The HPF discipline must be considered
first. To reduce the driving time and improve the service efficiency, the battery swapping van is
regulated only to provide the battery swapping service in its patrolling area. According to this point,
Figure 2. The general battery swapping service request queuing model.
In the battery swapping scenario, the utilization of individual EVs is normally independent
from each other, which indicates that their battery swapping requests are launched independently.
Therefore, for each single service area, the battery swapping service queuing model is the same. In this
paper, we base our analysis on a single service area. The general battery swapping service queuing
model for a single service area is shown in Figure 3.
Energies 2017, 10, 1667 12 of 21
Figure 2. The general battery swapping service request queuing model.
In the battery swapping scenario, the utilization of individual EVs is normally independent from
each other, which indicates that their battery swapping requests are launched independently.
Therefore, for each single service area, the battery swapping service queuing model is the same. In
this paper, we base our analysis on a single service area. The general battery swapping service
queuing model for a single service area is shown in Figure 3.
Figure 3. General queuing model for a single service area.
Based on this general battery swapping service queuing model for a single service area, there
are several submodules that need to be specified to determine a representative model.
4.2.1. Request Arrival
The request arrival determines the number and frequency of the battery swapping request. For
a single service area, the request arrival consists of two parts: the request launched in this area and
the request transferred from the adjacent service area. Both of them are independent of each other.
Commonly, we can assume a Poisson process to capture the request arrival.
4.2.2. Request Queuing Discipline
The request queuing discipline determines the order by which the requesting EVs will be served.
It would refer to the next EV to swap its battery. The disciplines can include HPF (select the request
with the highest priority first), FCFS (queuing requests according to the order of their request times),
NJN (select the request that is spatially closest to the current position of the battery swapping van
first), STDF (select the request that is the same driving direction to the battery swapping van first if
the requesting EV is in a parked state), HCF (select the request with the highest credit first), etc.
The SOC is a fundamental factor for battery swapping. The HPF discipline must be considered
first. To reduce the driving time and improve the service efficiency, the battery swapping van is
regulated only to provide the battery swapping service in its patrolling area. According to this point,
Figure 3. General queuing model for a single service area.
Based on this general battery swapping service queuing model for a single service area, there are
several submodules that need to be specified to determine a representative model.
4.2.1. Request Arrival
The request arrival determines the number and frequency of the battery swapping request. For a
single service area, the request arrival consists of two parts: the request launched in this area and
the request transferred from the adjacent service area. Both of them are independent of each other.
Commonly, we can assume a Poisson process to capture the request arrival.
4.2.2. Request Queuing Discipline
The request queuing discipline determines the order by which the requesting EVs will be served.
It would refer to the next EV to swap its battery. The disciplines can include HPF (select the request
with the highest priority first), FCFS (queuing requests according to the order of their request times),
13. Energies 2017, 10, 1667 13 of 21
NJN (select the request that is spatially closest to the current position of the battery swapping van
first), STDF (select the request that is the same driving direction to the battery swapping van first if the
requesting EV is in a parked state), HCF (select the request with the highest credit first), etc.
The SOC is a fundamental factor for battery swapping. The HPF discipline must be considered
first. To reduce the driving time and improve the service efficiency, the battery swapping van is
regulated only to provide the battery swapping service in its patrolling area. According to this point,
the SCF discipline seems to be adopted in our battery swapping service queuing process because it
minimizes the driving distance for the battery swapping van to reach the target EV and thus reduces
the time. Moreover, to reduce the risk of false reporting or to cancel the request by the EV user, the HCF
discipline should also be considered. To make the driving route of the battery swapping van simpler,
the STDF discipline needs to be considered. Thus, we should not queue the battery swapping service
using an only one discipline but consider them together. In the next section, a further discussion will
be given.
4.2.3. Request Departure
The request departure describes the specific battery swapping service process. Two factors
determine the request departure process: the service time of an individual battery swapping request
and the number of battery swapping vans. When a battery swapping van is selected, the requesting
EV is assigned to it. The former consists of two parts: the driving time that the battery swapping
van requires to reach the target EV and the time to swap a fully charged battery for the EV, which is
assumed to be constant Ts. These two time periods are clearly independent of each other.
The driving time is determined by the distance between the real-time position of battery swapping
van and that of the target EV, both driving speeds of the battery swapping van and target EV, and both
driving directions. Moreover, the driving time is reduced with a larger number of battery swapping
vans. This is because it is more likely for the requesting EV to be assigned a battery swapping van that
is spatially closer.
In this section, the analysis provides a basic theoretical reference for the performance metrics.
To better understand the battery swapping system that is based on a battery swapping van and
to provide more efficient and reasonable battery swapping service, the battery swapping request
scheduling mechanism is proposed that is based on further analysis.
5. Battery Swapping Service Request Scheduling
5.1. Request Queuing Model Adjustment
Once a battery swapping service request is assigned to a battery swapping van, it will be
completed after a certain time period. This time period is the service time of the current battery
swapping request. We can expect the total number of requesting EVs in the service coverage area to
be relatively large, and the number of battery swapping vans is relatively low. During the service
time, more than one new request would be launched. Moreover, one of the new requests would
probably be assigned to the same battery swapping van if the two requesting EVs are spatially
closer. Therefore, during peak commute hours, many requests would be assigned to the same battery
swapping van in a short time period, and each battery swapping van would have a battery swapping
service request queue. Then, the queuing model in Figure 3 will be transformed to a new one, as
shown in Figure 4.
This model changes the processing steps of the battery swapping service request. When a
request arrives, the first step is the selection of a battery swapping van. The request queuing
process that follows some queuing disciplines is set to be the second step. With the consideration
of real-time positions and driving directions of the battery swapping vans and of the requesting EV,
the corresponding request is assigned to the proper battery swapping van following the principle of a
spatially closer assignment.
14. Energies 2017, 10, 1667 14 of 21
This model changes the processing steps of the battery swapping service request. When a request
arrives, the first step is the selection of a battery swapping van. The request queuing process that
follows some queuing disciplines is set to be the second step. With the consideration of real-time
positions and driving directions of the battery swapping vans and of the requesting EV, the
corresponding request is assigned to the proper battery swapping van following the principle of a
spatially closer assignment.
Figure 4. New queuing model for a single service area.
The queue of the entire service area is divided into several sub-queues according to the number
of battery swapping vans. The request of the same sub-queue will be served by the same battery
swapping van, and the number of requests of each sub-queue is significantly lower than of the entire
queue. In the next sub-section, the request scheduling of a single sub-queue is discussed.
5.2. Request Scheduling for Single Battery Swapping Van
5.2.1. Waiting Time Thresholds for EV Users’ Satisfaction
EV users will commonly evaluate the battery swapping service in their mind when their requests
are completed. The high or low of the evaluation shows their satisfaction, which mainly depends on
their waiting times. Theoretically, the shorter time that EV users wait, the stronger satisfaction they
have. However, in the realistic battery swapping scenario, EV user’s satisfaction does not immediately
change with the change of the waiting time. It only obviously changes when the waiting time is beyond
some expected threshold. Furthermore, for different EV users, their expected and acceptable waiting
time thresholds are not the same.
The EV user’s acceptable waiting time threshold is closely related to SOC. Definitely, only without
getting a service when SOC falls below the energy threshold can the EV user feel dissatisfied. For a
unified analysis, we use an acceptable waiting time threshold of request instead of that of the EV user.
Table 4 shows the different waiting time thresholds of request for different satisfaction levels according
to the request priority.
Table 4. Waiting time thresholds of request for different satisfaction levels.
Request Priority
Satisfaction
Very Satisfied Satisfied Acceptable
1 (SOC ≤ 5%) SOC*s/v 2T0 3T0
2 (5% < SOC ≤ 10%) (SOC-5%)s/v max(SOC*s/v, 5%s/v + T0) 3T0
3 (10% < SOC ≤ 20%) (SOC-10%)s/v (SOC-5%)s/v max(SOC*s/v, 10%s/v + T0)
4 (SOC > 20%) (SOC-20%)s/v (SOC-5%)s/v max(SOC*s/v, 20%s/v + T0)
We establish four satisfaction levels: very satisfied, satisfied, acceptable and dissatisfied.
T0, (2.5%s/v < T0 ≤ 5%s/v) is a constant, which is set according to the commute hour. The comparison
of Tables 3 and 4 indicates that the change of EV user’s satisfaction is synchronized with the change of
real-time priority of the corresponding request. Both of them are defined, as SOC falls below some
energy thresholds. If the request is completed before its priority changes for the first time, the service
is very satisfactory. The more times the request priority changes, the lower the level of EV user
satisfaction. The difference between different priority requests is the number of changes that they can
endure in the same satisfaction level.
15. Energies 2017, 10, 1667 15 of 21
5.2.2. Scheduling Principle
We denoted Tw
id as the waiting time of EV user Uid, which is determined from the time when
Uid launches the request Rid to the time when Rid is completed. We denote Ts
id as the satisfactory
waiting time thresholds of Rid in column 3 of Table 4. If Tw
id is not greater than Ts
id, Tw
id is considered
as a satisfactory waiting time. We should complete the requests within the satisfactory waiting time.
From this point of view, Rid with a shorter Ts
id seems to be served earlier.
However, the change of request priority mainly decides the EV user’s satisfaction, as shown in
Table 4. Sometimes, the shorter Ts
id does not mean less SOC. It is consistent with the fact that everyone
actually wants to be served earlier and has a high expectation in mind. Therefore, Tw
id should be
considered instead of Ts
id, and we should also consider a request priority.
Actually, the request with priority 1 should be immediately completed, and it is not reasonable to
complete the requests with priority 3 and 4 in their very satisfied waiting time thresholds if there are
still requests with priority 1 and 2. Thus, the very satisfied waiting time threshold of Rid in column 2
of Table 4 is not considered in the request scheduling process.
We should complete as many requests as possible within the satisfactory waiting time.
Therefore, based on the abovementioned analysis, three request scheduling principles can be concluded:
(1) Requests should be completed within the satisfactory waiting time as much as possible especially
the requests with a priority 1 and 2.
(2) When the satisfaction level is the same, Rid with a higher priority should be served earlier.
(3) When both the satisfaction level and priority are the same, Rid with a shorter Tw
id should be
served earlier.
5.2.3. Scheduling Model
When the battery swapping van is driving to the requesting EV after it accepts the request,
it may receive two types of new requests: (1) the new requesting EV is on the driving route of the
battery swapping van; (2) the new requesting EV is not on the driving route of the battery swapping
van. The second type of request can be further divided into three types: (1) the new request has a
higher priority compared with that of the current target; (2) the new request has the same priority;
(3) the new request has a lower priority. Whether to change the service order or not if both orders are
acceptable according to the scheduling principles and how to change the service request queuing order
if more new requests arrive after we change the service order are what we need to deeply consider
and determine.
To solve this problem, we divide the entire request queue of a single battery swapping van into
two sub-queues: the head sub-queue Qh and the tail sub-queue Qt. The length of Qh is a constant N.
When a new request Rid arrives, if Qh is not full, then enqueue Rid into Qh. If Qh is full, then enqueue
Rid into Qt following the scheduling principles. We only schedule the service order in Qh. After one
request is completed, the head request of Qt will be moved into Qh and is scheduled if Qt is not empty.
The scheduling model for the single battery swapping van is shown in Figure 5.
Energies 2017, 10, 1667 15 of 21
everyone actually wants to be served earlier and has a high expectation in mind. Therefore,
w
id
T
should be considered instead of
s
id
T , and we should also consider a request priority.
Actually, the request with priority 1 should be immediately completed, and it is not reasonable
to complete the requests with priority 3 and 4 in their very satisfied waiting time thresholds if there
are still requests with priority 1 and 2. Thus, the very satisfied waiting time threshold of id
R in
column 2 of Table 4 is not considered in the request scheduling process.
We should complete as many requests as possible within the satisfactory waiting time.
Therefore, based on the abovementioned analysis, three request scheduling principles can be
concluded:
(1) Requests should be completed within the satisfactory waiting time as much as possible
especially the requests with a priority 1 and 2.
(2) When the satisfaction level is the same, id
R with a higher priority should be served earlier.
(3) When both the satisfaction level and priority are the same, id
R with a shorter
w
id
T should be
served earlier.
5.2.3. Scheduling Model
When the battery swapping van is driving to the requesting EV after it accepts the request, it
may receive two types of new requests: (1) the new requesting EV is on the driving route of the battery
swapping van; (2) the new requesting EV is not on the driving route of the battery swapping van.
The second type of request can be further divided into three types: (1) the new request has a higher
priority compared with that of the current target; (2) the new request has the same priority; (3) the
new request has a lower priority. Whether to change the service order or not if both orders are
acceptable according to the scheduling principles and how to change the service request queuing
order if more new requests arrive after we change the service order are what we need to deeply
consider and determine.
To solve this problem, we divide the entire request queue of a single battery swapping van into
two sub-queues: the head sub-queue h
Q and the tail sub-queue t
Q . The length of h
Q is a constant
N. When a new request id
R arrives, if h
Q is not full, then enqueue id
R into h
Q . If h
Q is full, then
enqueue id
R into t
Q following the scheduling principles. We only schedule the service order in
h
Q . After one request is completed, the head request of t
Q will be moved into h
Q and is scheduled
if t
Q is not empty. The scheduling model for the single battery swapping van is shown in Figure 5.
h
Q
t
Q
Figure 5. Scheduling model for the single battery swapping van.
In actual operations, the battery swapping service is constrained by the limited carrying capacity
of fully charged batteries. Hence, the constant length N of h
Q should not be too large. Once the
battery swapping van needs to replenish its fully charged battery supply, h
Q needs to be requeued
according to the real-time position of the battery swapping van.
Figure 5. Scheduling model for the single battery swapping van.
In actual operations, the battery swapping service is constrained by the limited carrying capacity
of fully charged batteries. Hence, the constant length N of Qh should not be too large. Once the battery
swapping van needs to replenish its fully charged battery supply, Qh needs to be requeued according
to the real-time position of the battery swapping van.
16. Energies 2017, 10, 1667 16 of 21
5.2.4. Scheduling Strategy
Based on the scheduling model, we propose a scheduling strategy that follows the scheduling
principles in this sub-section.
If Qh is assumed as < R1, R2, . . . , RN > at time t, the waiting time Tw
i (i = 1, 2, . . . , N) of the EV
user Ui is calculated as:
Tw
i = Tw
i−1 + Td
i−1,i + Ts (3)
where, Td
i−1,i is the time that battery swapping van drives to Ui. < Tw
1 , Tw
2 , . . . , Tw
N > is
consequently obtained.
Satisfied scheduling permutation: For N requests of Qh, if in a request permutation
Pj =< R1, R2, . . . , RN >, (j ∈ 1, 2, . . . N!), Tw
i ≤ Ts
i for each Ri, then Pj is a satisfied
scheduling permutation.
For Qh, there may be more than one satisfied scheduling permutation. We continue to consider
request priority. We denote Oi as the value of priority of Ri. For the pair of any two requests
< Ri, Rj >, (i < j) in one Pj, if Oi ≤ Oj, then < Ri, Rj > is called a positive-order pair.
Positive-order satisfied scheduling permutation: For Qh, a satisfied scheduling permutation
that has the most positive-order pairs is called a positive-order satisfied scheduling permutation.
There still may be more than one positive-order satisfied scheduling permutation, where the
average waiting time Tw of N requests in a scheduling permutation is considered to serve more
requests. Tw is calculated as:
Tw =
N
∑
i=1
Tw
i /N (4)
Finally, we determine the positive-order satisfied scheduling permutation with the minimum Tw
and provide the battery swapping service following the requesting order.
If there is only one satisfied scheduling permutation, then it is our needed scheduling result.
If there is no satisfied scheduling permutation, then a permutation with a satisfied scheduling of
request with priority 1 and 2 should be chosen and scheduled following the abovementioned process.
Then, we propose a minimum waiting time based on priority and satisfaction scheduling strategy
(MWT-PS), as shown in Figure 6.
5.2.4. Scheduling Strategy
Based on the scheduling model, we propose a scheduling strategy that follows the scheduling
principles in this sub-section.
If h
Q is assumed as 1 2
, ,..., N
R R R
< > at time t, the waiting time ( 1,2,..., )
w
i
T i N
= of the
EV user i
U is calculated as:
1 1,
− −
= + +
w w d
i i i i s
T T T T (3)
where, 1,
d
i i
T− is the time that battery swapping van drives to i
U . 1 2
, ,...,
w w w
N
T T T
< > is
consequently obtained.
Satisfied scheduling permutation: For N requests of h
Q , if in a request permutation
1 2
, ,...,
j N
P R R R
=< > , ( 1, 2,... !)
j N
∈ ,
w s
i i
T T
≤ for each i
R , then j
P is a satisfied scheduling
permutation.
For h
Q , there may be more than one satisfied scheduling permutation. We continue to consider
request priority. We denote i
O as the value of priority of i
R . For the pair of any two requests
, ,( )
i j
R R i j
< > < in one j
P , if i j
O O
≤ , then ,
i j
R R
< > is called a positive-order pair.
Positive-order satisfied scheduling permutation: For h
Q , a satisfied scheduling permutation
that has the most positive-order pairs is called a positive-order satisfied scheduling permutation.
There still may be more than one positive-order satisfied scheduling permutation, where the
average waiting time
w
T of N requests in a scheduling permutation is considered to serve more
requests.
w
T is calculated as:
1
/
=
=
N
w w
i
i
T T N (4)
Finally, we determine the positive-order satisfied scheduling permutation with the minimum
w
T and provide the battery swapping service following the requesting order.
If there is only one satisfied scheduling permutation, then it is our needed scheduling result. If
there is no satisfied scheduling permutation, then a permutation with a satisfied scheduling of
request with priority 1 and 2 should be chosen and scheduled following the abovementioned process.
Then, we propose a minimum waiting time based on priority and satisfaction scheduling
strategy (MWT-PS), as shown in Figure 6.
h
Q
w
T
Figure 6. MWT-PS scheduling strategy.
Figure 6. MWT-PS scheduling strategy.
6. Simulation Results
In this section, the battery swapping service is simulated, and the performance of MWT-PS is
evaluated. We chose an urban environment that is approximated by the Haidian district in Beijing as
the simulation scenario. The entire simulation scenario is divided into four service areas of equal size.
17. Energies 2017, 10, 1667 17 of 21
We assume that the battery swapping vans are able to complete the battery swapping requests of EVs
at any location.
In the design of a mobile battery swapping system, in general, there are some parameters that
will significantly affect the performance of the system. We evaluate the system design using two
main metrics that represent how well this system is operating. The first metric is the miss ratio rm,
which considers the number of requests that are not completed by the acceptable waiting time of the
EV. We denoted M as the total number of requests served during the mobile battery swapping process,
and M0 as the number of requests that fail to be completed. rm is calculated as:
rm = M0/M (5)
The second metric is the average response time, which is defined as the time taken from when the
EV sends out its battery swapping request to the time the request is completed.
In this paper, a fully charged battery is swapped with a fixed swapping time. Due to the limited
carrying capacity of the fully charged batteries of each battery swapping van, the battery swapping
van without any available fully charged batteries needs to return to battery swapping stations to
replenish fully charged batteries. Figure 7 presents their impact on the mobile battery swapping
service, examines the number of 1–5 for battery swapping vans in each single service area and the fully
charged battery capacities of 5–20 for each battery swapping van.
Energies 2017, 10, 1667 17 of 21
6. Simulation Results
In this section, the battery swapping service is simulated, and the performance of MWT-PS is
evaluated. We chose an urban environment that is approximated by the Haidian district in Beijing as
the simulation scenario. The entire simulation scenario is divided into four service areas of equal size.
We assume that the battery swapping vans are able to complete the battery swapping requests of EVs
at any location.
In the design of a mobile battery swapping system, in general, there are some parameters that
will significantly affect the performance of the system. We evaluate the system design using two main
metrics that represent how well this system is operating. The first metric is the miss ratio m
r , which
considers the number of requests that are not completed by the acceptable waiting time of the EV.
We denoted M as the total number of requests served during the mobile battery swapping process,
and 0
M as the number of requests that fail to be completed. m
r is calculated as:
0 /
=
m
r M M (5)
The second metric is the average response time, which is defined as the time taken from when
the EV sends out its battery swapping request to the time the request is completed.
In this paper, a fully charged battery is swapped with a fixed swapping time. Due to the limited
carrying capacity of the fully charged batteries of each battery swapping van, the battery swapping
van without any available fully charged batteries needs to return to battery swapping stations to
replenish fully charged batteries. Figure 7 presents their impact on the mobile battery swapping
service, examines the number of 1–5 for battery swapping vans in each single service area and the
fully charged battery capacities of 5–20 for each battery swapping van.
(a)
(b)
Figure 7. performance evaluation with respect to the number of battery swapping vans and fully
charged battery capacity (a) miss ratio; (b) average response time.
Figure 7. performance evaluation with respect to the number of battery swapping vans and fully
charged battery capacity (a) miss ratio; (b) average response time.
Larger battery swapping vans and larger fully charged capacity improve the performance in terms
of both the miss ratio and average response time, which is intuitive. Although the small fully charged
18. Energies 2017, 10, 1667 18 of 21
battery capacity seems to lead to large miss ratio and average response time because of a relatively
frequent fully charged battery replenishment, the large fully charged battery capacity cannot clearly
improve the performance metrics, especially when the number of battery swapping vans is larger
than 2 in each single service area. Thus, the number of battery swapping vans and the performance
of service queue scheduling are more important as long as the fully charged battery capacity is not
too small.
We further evaluate the performance of service queue scheduling and compare between three
service scheduling disciplines: FCFS strategy, NJN strategy, and our MWT-PS strategy with five battery
swapping vans, each with a fully charged battery capacity of 20 in a single service area. In addition to
the miss ratio and average response time, there is still an important metric. It is the satisfaction ratio
with priority 1 and 2, which considers the number of requests with priority 1 and 2 that are completed
by the satisfied waiting time of the EV. The calculation of satisfaction ratio is similar to the miss ratio.
Figure 8 shows the change of three performance metrics with the increasing battery swapping service
requests in a commute hour. The results show that the battery swapping service system with our
MWT-PS service scheduling strategy can provide a relatively high-quality battery swapping service
for the EV users, especially those with more eager requirement for the battery swapping service.
The average response time is obtained in the experimental scenario. In the actual battery swapping
service scenario, the time may increase to a certain extent due to device standardization, proficiency,
traffic, and other force majeure.
Energies 2017, 10, 1667 18 of 21
Larger battery swapping vans and larger fully charged capacity improve the performance in
terms of both the miss ratio and average response time, which is intuitive. Although the small fully
charged battery capacity seems to lead to large miss ratio and average response time because of a
relatively frequent fully charged battery replenishment, the large fully charged battery capacity
cannot clearly improve the performance metrics, especially when the number of battery swapping
vans is larger than 2 in each single service area. Thus, the number of battery swapping vans and the
performance of service queue scheduling are more important as long as the fully charged battery
capacity is not too small.
We further evaluate the performance of service queue scheduling and compare between three
service scheduling disciplines: FCFS strategy, NJN strategy, and our MWT-PS strategy with five
battery swapping vans, each with a fully charged battery capacity of 20 in a single service area. In
addition to the miss ratio and average response time, there is still an important metric. It is the
satisfaction ratio with priority 1 and 2, which considers the number of requests with priority 1 and 2
that are completed by the satisfied waiting time of the EV. The calculation of satisfaction ratio is
similar to the miss ratio. Figure 8 shows the change of three performance metrics with the increasing
battery swapping service requests in a commute hour. The results show that the battery swapping
service system with our MWT-PS service scheduling strategy can provide a relatively high-quality
battery swapping service for the EV users, especially those with more eager requirement for the
battery swapping service. The average response time is obtained in the experimental scenario. In the
actual battery swapping service scenario, the time may increase to a certain extent due to device
standardization, proficiency, traffic, and other force majeure.
(a) (b)
(c)
Figure 8. Performance evaluation with respect to the number of requests (a) miss ratio; (b) average
response time; (c) satisfaction ratio with priority 1 and 2.
The realization of battery swapping systems that are based on mobile battery swapping vans is
still a significant engineering challenge. However, there can be a design possibility for a mobile
Figure 8. Performance evaluation with respect to the number of requests (a) miss ratio; (b) average
response time; (c) satisfaction ratio with priority 1 and 2.
The realization of battery swapping systems that are based on mobile battery swapping vans is
still a significant engineering challenge. However, there can be a design possibility for a mobile battery
19. Energies 2017, 10, 1667 19 of 21
swapping system, and the simulation results show that this novel approach can be used as a reference
for a future system.
7. Conclusions
This paper presents a novel approach for providing a battery swapping service for EVs, which is
provided by mobile battery swapping vans. A battery swapping van can carry tens of fully charged
batteries and drive to an EV to swap a battery within a relatively short fixed period of time.
A reasonable EV battery swapping architecture that is based on a battery swapping van is established
in this paper. The function and role of each participant and relationships between each participant are
determined, especially their changes compared with the battery charging service. The profit mode
and some practical factors are discussed. The battery swapping service is described in detail. We set
the priorities of the battery swapping service requests according to SOC and their corresponding
changes. The general service request queuing models for the entire battery swapping system and
single service area are presented. To provide the battery swapping service efficiently and effectively,
the battery swapping request scheduling is well analyzed, and the MWT-PS scheduling strategy based
on priority and EV users’ satisfaction is proposed. Finally, the battery swapping service is simulated,
and the performance of MWT-PS is evaluated in the simulation scenarios. The simulation results show
that this novel approach can be used as a reference for a future system and provides a reasonable
and satisfactory battery swapping service for EVs. As a future work, we will seek to study the exact
specifications of implementation of a battery swapping service that is based on battery swapping vans
to make the mobile battery swapping system come true earlier.
Acknowledgments: This work is supported by the National Science and Technology Support Program of China
under Grant 2015BAG10B01.
Author Contributions: This work is the output of research projects undertaken by Shaoyong Guo. Shaoyong Guo
developed the topic, revised, reviewed, and supervised the whole paper. Sujie Shao performed the calculation,
experimentation and paper writing. Xuesong Qiu reviewed and improved the paper.
Conflicts of Interest: The authors declare no conflict of interest.
References
1. Yabe, K.; Shinoda, Y.; Seki, T.; Tanaka, H.; Akisawa, A. Market penetration speed and effects on CO2
reduction of electric vehicles and plug-in hybrid electric vehicles in Japan. Energy Policy 2012, 45, 529–540.
[CrossRef]
2. Zhang, X.; Wang, G.B. Optimal Dispatch of Electric Vehicle Batteries between Battery Swapping Stations and
Charging Stations. In Proceedings of the 2016 IEEE Power and Energy Society General Meeting (PESGM),
Boston, MA, USA, 17–21 July 2016; pp. 1–5.
3. Zhang, C.W.; Cheng, Y. Research on joint planning model for EVs charging/swapping facilities.
In Proceedings of the 2016 China International Conference on Electricity Distribution (CICED), Xi’an, China,
10–13 August 2016; pp. 1–8.
4. Nilsson, M. Electric Vehicles: The Phenomenon of Range Anxiety; ELVIRE Consortium FP7-ICT-2009-4-249105;
ELVIRE Report: Babenhausen, Germany, 2011; pp. 1–14.
5. Franke, T.; Neumann, I.; Buhler, F.; Cocron, P.; Krems, J. Experiencing range in an electric vehicle:
Understanding psychological barriers. Appl. Psychol. 2012, 61, 368–391. [CrossRef]
6. Jamian, J.J.; Mustafa, M.W.; Mokhlis, H.; Baharudin, M.A. Simulation study on optimal placement and sizing
of Battery Switching Station units using Artificial Bee Colony algorithm. Int. J. Electr. Power 2014, 55, 592–601.
[CrossRef]
7. Wu, T.H.; Pang, G.H.; Choy, K.L.; Lam, H.Y. An optimization model for a battery swapping station in
Hong Kong. In Proceedings of the 2015 IEEE Transportation Electrification Conference and Expo (ITEC),
Dearborn, MI, USA, 14–17 June 2015; pp. 1–6.
20. Energies 2017, 10, 1667 20 of 21
8. Rogowsky, M. 6 Reasons Tesla’s Battery Swapping Could Take It to a ‘Better Place’. 2013. Available online:
http://www.forbes.com/sites/markrogowsky/2013/06/21/6-reasons-teslas-battery-swapping-could-takeit-
to-a-better-place/ (accessed on 21 June 2013).
9. Wirasingha, S.; Schofield, N.; Emadi, A. Plug-in hybrid electric vehicle developments in the US: Trends,
barriers, economic feasibility. In Proceedings of the 2008 IEEE Vehicle Power and Propulsion Conference
(VPPC), Harbin, China, 3–5 September 2008; pp. 1–8.
10. Lu, G.J.; Zhou, Y.P. A Flat-Plate Type Zinc Nickel Secondary Battery with Replaceable Electrode Plate and
Electrolyte. CN 201120154152.9, 16 November 2011.
11. Mirchandani, P.; Adler, J.; Madsen, B.G. New logistical issues in using electric vehicle fleets with battery
exchange infrastructure. Procedia Soc. Behav. Sci. 2014, 108, 3–14. [CrossRef]
12. Sun, B.; Tan, X.Q.; Tsang, H.K. Optimal Charging Operation of Battery Swapping Stations with
QoS Guarantee. In Proceedings of the 2014 IEEE International Conference on Smart Grid Communications
(SmartGridComm), Venice, Italy, 3–6 November 2014; pp. 13–18.
13. Rao, R.; Zhang, X.P.; Xie, J.; Ju, L.W. Optimizing electric vehicle users’ charging behavior in battery swapping
mode. Appl. Energy. 2015, 155, 547–559. [CrossRef]
14. Adler, J.D.; Mrichandani, P.B. Online routing and battery reservations for electric vehicles with swappable
batteries. Transp. Res. Part B 2014, 70, 285–302. [CrossRef]
15. Lu, G.J.; Zhou, Y.P. A Electric Vehicle with Bottom Lateral Linkage Battery Swapping and Its Battery
Swapping Devices. CN 201310164242.X, 16 October 2013.
16. Gao, X.J.; Zhao, J.L.; Shang, W.Z.; Wang, T.B.; Wang, X. A Mobile Electric Vehicle Battery Swapping Van for
Emergency. CN 201120341622.2, 2 May 2012.
17. Huang, S. The effects of electric vehicles on residential households in the city of Indianapolis. Energy Policy
2012, 49, 442–455. [CrossRef]
18. Hodge, M.S.; Huang, S.; Shukla, A.; Pekny, J.F.; Reklaitis, G.V. The effects of vehicle-to-grid systems on wind
power integration in California. Comput. Aided Chem. Eng. 2010, 28, 1039–1044.
19. Meyer, M.K.; Schneider, K.; Pratt, R. Impacts Assessment of Plug-In Hybrid Vehicles on
Electric Utilities and Regional U.S. Power Grids Part 1: Technical Analysis. Available online:
https://www.semanticscholar.org/paper/Impacts-Assessment-of-Plug-in-Hybrid-Vehicles-on-E-Kintner-
Meyer-Schneider/4e3d79b0ec1e87569bb2bb932a85c16180672573?tab=abstract (accessed on 19 October 2017).
20. Eppstein, M.; Grover, D.; Marshall, J.; Rizzo, D. An agent-based model to study market penetration of plug-in
hybrid electric vehicles. Energy Policy 2011, 39, 3789–3802. [CrossRef]
21. Wang, Y.W.; Lin, C.C. Locating multiple types of recharging stations for battery-powered electric vehicle
transport. Transp. Res. Part E 2013, 58, 76–87. [CrossRef]
22. Xu, Z.W.; Hu, Z.C.; Song, Y.H.; Luo, Z.W.; Zhan, K.Q.; Shi, H. Coordinated Charging of Plug-in Electric
Vehicles in Charging Stations. Autom. Electr. Power Syst. 2012, 36, 38–43.
23. Martin, P.S.; Lumbreras, S.; Alberdi, A.A. Stochastic Programming Applied to EV Charging Points for Energy
and Reserve Service Markets. IEEE Trans. Power Syst. 2016, 31, 198–205. [CrossRef]
24. Tan, J.; Wang, L.F. Real-Time Charging Navigation of Electric Vehicles to Fast Charging Stations A
Hierarchical Game Approach. IEEE Trans. Smart Grid 2015, 99. [CrossRef]
25. Chen, Q.F.; Liu, N.; Lu, X.Y.; Zhang, J.H. A Heuristic Charging Strategy for Real-Time Operation of
PV-based Charging Station for Electric Vehicles. In Proceedings of the 2014 IEEE Innovative Smart Grid
Technologies-Asia (ISGT ASIA), Kuala Lumpur, Malaysia, 20–23 May 2014; pp. 465–469.
26. Shukla, A.; Pekny, J.; Venkatasubramanian, V. An optimization framework for cost effective design of
refueling station infrastructure for alternative fuel vehicles. Comput. Chem. Eng. 2011, 35, 1431–1438.
[CrossRef]
27. Yang, J.; Sun, H. Battery swap station location-routing problem with capacitated electric vehicles.
Comp. Oper. Res. 2015, 55, 217–232. [CrossRef]
28. Infante, W.F.; Ma, J.; Chi, Y.Y. Operational Strategy and Load Profile Sensitivity Analysis for an Electric
Vehicle Battery Swapping Station. In Proceedings of the 2016 IEEE International Conference on Power
System Technology (POWERCON), Wollongong, NSW, Australia, 28 September–1 October 2016; pp. 1–6.
29. Sarker, M.R.; Pandzic, H.; Ortega-Vazquez, M.A. Optimal Operation and Services Scheduling for an Electric
Vehicle Battery Swapping Station. IEEE Trans. Power Syst. 2015, 30, 901–910. [CrossRef]