The document discusses electrochemical energy storage and its importance for alternative energy applications. It outlines some key challenges with energy storage, including the need for devices with high power and energy capabilities, long life, fast charging, and portability. The author proposes using hybrid energy storage systems that integrate multiple device types to optimize performance for different applications and timescales. The remainder of the document focuses on lithium-ion battery limitations and using mechanical models to understand capacity fade through stresses induced during operation.
There is need for an energy storage device capable of transferring high power in transient situations
aboard naval vessels. Currently, batteries are used to accomplish this task, but previous research has
shown that when utilized at high power rates, these devices deteriorate over time causing a loss in lifespan.
It has been shown that a hybrid energy storage configuration is capable of meeting such a demand while
reducing the strain placed on individual components. While designing a custom converter capable of
controlling the power to and from a battery would be ideal for this application, it can be costly to develop
when compared to purchasing commercially available products. Commercially available products offer
limited controllability in exchange for their proven performance and lower cost point - often times only
allowing a system level control input without any way to interface with low level controls that are
frequently used in controller design. This paper proposes the use of fuzzy logic control in order to provide
a system level control to the converters responsible for limiting power to and from the battery. A system
will be described mathematically, modeled in MATLAB/Simulink, and a fuzzy logic controller will be
compared with a typical controller.
ENERGY MANAGEMENT SYSTEM FOR CRITICAL LOADS USING POWER ELECTRONICSrenukasningadally
The work aims at an Energy Management System (EMS) for Critical loads using Power Electronics. Here hybrid power sources (Grid and Solar cells) with battery have been used to supply the power to the critical loads at all times, suppose an end user increases his critical loads or non-critical loads this EMS system helps to maintain continuous power supply to these loads. Solar or Photovoltaic cells have been used for storing energy through battery and these batteries will discharge the stored energy at two conditions, one is when grid is shut down for short duration or for a long duration and another one is when there sudden increase in load by users
Stand-alone Hybrid systems become appreciating issues that ensure the required electricity to consumers. The development of a stand-alone Hybrid system becomes a necessity for multiple applications The enhance energy security. To achieve this objective, we have proposed an accurate dynamic model using Multi-Agent System (MAS) in which a solar energy System (SES) serves as the main load supply, an energy Backup System (ERS) is based on a fuel cell and Electrolyzer for long-term energy storage and an Ultra Capacitor (UCap) storage system deployed as a short-time storage. To cooperate with all systems, an Intelligent Power Management (IPM) based on a specific MAS is included. Thus, to prove the performance of the system, we tested and simulated it using the Matlab/Simulink environment.
Daymark Energy Advisors Principal Consultant Stan Faryniarz spoke on energy storage technologies as part of the session "Storage Project & Policy Successes: Enhancing Renewables Integration & Resilience" at The 2016 Renewable Energy Vermont (REV 2016) Conference.
There is need for an energy storage device capable of transferring high power in transient situations
aboard naval vessels. Currently, batteries are used to accomplish this task, but previous research has
shown that when utilized at high power rates, these devices deteriorate over time causing a loss in lifespan.
It has been shown that a hybrid energy storage configuration is capable of meeting such a demand while
reducing the strain placed on individual components. While designing a custom converter capable of
controlling the power to and from a battery would be ideal for this application, it can be costly to develop
when compared to purchasing commercially available products. Commercially available products offer
limited controllability in exchange for their proven performance and lower cost point - often times only
allowing a system level control input without any way to interface with low level controls that are
frequently used in controller design. This paper proposes the use of fuzzy logic control in order to provide
a system level control to the converters responsible for limiting power to and from the battery. A system
will be described mathematically, modeled in MATLAB/Simulink, and a fuzzy logic controller will be
compared with a typical controller.
ENERGY MANAGEMENT SYSTEM FOR CRITICAL LOADS USING POWER ELECTRONICSrenukasningadally
The work aims at an Energy Management System (EMS) for Critical loads using Power Electronics. Here hybrid power sources (Grid and Solar cells) with battery have been used to supply the power to the critical loads at all times, suppose an end user increases his critical loads or non-critical loads this EMS system helps to maintain continuous power supply to these loads. Solar or Photovoltaic cells have been used for storing energy through battery and these batteries will discharge the stored energy at two conditions, one is when grid is shut down for short duration or for a long duration and another one is when there sudden increase in load by users
Stand-alone Hybrid systems become appreciating issues that ensure the required electricity to consumers. The development of a stand-alone Hybrid system becomes a necessity for multiple applications The enhance energy security. To achieve this objective, we have proposed an accurate dynamic model using Multi-Agent System (MAS) in which a solar energy System (SES) serves as the main load supply, an energy Backup System (ERS) is based on a fuel cell and Electrolyzer for long-term energy storage and an Ultra Capacitor (UCap) storage system deployed as a short-time storage. To cooperate with all systems, an Intelligent Power Management (IPM) based on a specific MAS is included. Thus, to prove the performance of the system, we tested and simulated it using the Matlab/Simulink environment.
Daymark Energy Advisors Principal Consultant Stan Faryniarz spoke on energy storage technologies as part of the session "Storage Project & Policy Successes: Enhancing Renewables Integration & Resilience" at The 2016 Renewable Energy Vermont (REV 2016) Conference.
Modeling, Control and Power Management Strategy of a Grid connected Hybrid En...IJECEIAES
This paper presents the detailed modeling of various components of a grid connected hybrid energy system (HES) consisting of a photovoltaic (PV) system, a solid oxide fuel cell (SOFC), an electrolyzer and a hydrogen storage tank with a power flow controller. Also, a valve controlled by the proposed controller decides how much amount of fuel is consumed by fuel cell according to the load demand. In this paper fuel cell is used instead of battery bank because fuel cell is free from pollution. The control and power management strategies are also developed. When the PV power is sufficient then it can fulfill the load demand as well as feeds the extra power to the electrolyzer. By using the electrolyzer, the hydrogen is generated from the water and stored in storage tank and this hydrogen act as a fuel to SOFC. If the availability of the power from the PV system cannot fulfill the load demand, then the fuel cell fulfills the required load demand. The SOFC takes required amount of hydrogen as fuel, which is controlled by the PID controller through a valve. Effectiveness of this technology is verified by the help of computer simulations in MATLAB/SIMULINK environment under various loading conditions and promising results are obtained.
Modeling and Steady State Response Analysis of Interconnected Hybrid Renewable Energy Network with Embedded VSC - MTDC Transmission System for Secure and Efficient Power Delivery
Isolated Wind Hydro Hybrid Generation System with Battery StorageIJMER
In this paper, a new isolated wind- hydro hybrid generation system comprising one squirrel -cage induction generator (SCIG) driven by a variable-speed wind turbine and another synchronous generator driven by constant power hydro turbine feeding three phase four wire local loads is proposed. The system utilizes two back to back connected voltage-source converters (VSCs) with a battery energy storage system at their dc link. The main objective of the control algorithm for the VSC is to achieve control of the magnitude and the frequency of the load voltage. The proposed wind-hydro hybrid system has a capability of bidirectional active- and reactive-power flow, by which it controls the magnitude and the frequency of the load voltage. The proposed electromechanical system is modelled and simulated in MATLAB using Simulink.
Operation and Control of Grid Connected Hybrid AC/DC Microgrid using Various RESIAES-IJPEDS
This paper proposes a Hybrid AC/DC Microgrid in alliance with Photo Voltaic (PV) energy, Wind Energy and Proton Exchange Membrane (PEM) Fuel cells. Microgrids are becoming increasingly attractive to the researchers because of the less greenhouse gases, low running cost, and flexibility to operate in connection with utility grid. The Hybrid AC/DC Microgrid constitutes independent AC and DC subgrids, where all the corresponding sources and loads are connected to their respective buses and these buses are interfaced using an interfacing converter. The Hybrid AC/DC Microgrid increases system efficiency by reducing the multiple reverse conversions involved in conventional RES integration to grid. A Small Hybrid AC/DC Microgrid in grid connected mode was modeled and simulated in MATLAB- SIMULINK environment. The simulation results prove the stable operation considering the uncertainty of generations and loads.
Simulation of MPPT Algorithm Based Hybrid Wind-Solar-Fuel Cell Energy SystemIJMER
This paper presents a new system configuration of the front-end rectifier stage for a hybrid
wind/photovoltaic energy system. This configuration allows the two sources to supply the load
separately or simultaneously depending on the availability of the energy sources. The inherent nature of
this Cuk-SEPIC fused converter, additional input filters are not necessary to filter out high frequency
harmonics. Harmonic content is detrimental for the generator lifespan, heating issues, and efficiency.
The fused multiinput rectifier stage also allows Maximum Power Point Tracking (MPPT) to be used to
extract maximum power from the wind and sun when it is available. An adaptive MPPT algorithm will
be used for the wind system and a standard perturb and observe method will be used for the PV system.
Operational analysis of the proposed system will be discussed in this paper. Simulation results are given
to highlight the merits of the proposed circuit.
This paper discusses about a LabVIEW based controller for the hybrid renewable energy system operated AC-DC microgrid with the major objectives of: i) predicting the power generation potential of the solar–PV and wind generators ii) effective power management iii) load scheduling based on the available power with the renewable sources and iv) grid/islanding mode of operation of the microgrid. In order topredict the output power of wind generator and Solar-PV system, an artificial neural network is developed.The laboratory-scale model of three phase, 400 V, 10 kVA microgrid structure is developed at National Institute of Technology Calicut, India. The developed LabVIEW based controller has been tested successfully for a real-time load and source in the laboratory environment. Test results show that the designed controller is effectively managing the output powerof the primary energy sources under different scenarios.
Standalone photovoltaic array fed induction motor driven water pumping system IJECEIAES
Due to the absence of energy transmission lines connected to the water pumping sites in remote areas, problems related to the electrical power outages and the environmental degradation caused by fossil fuel. For this one of the most conceived solutions is the photovoltaic water pumping technology which has the advantage of being sustainable and respectful of the environment to supply water to rural areas. To ensure the need of water, especially for domestic use and small communities, in this article, the photovoltaic energy system for autonomous water pumping using the induction motor was presented, particularly adapted to the isolated regions. Pumping system consists of four photovoltaic (PV) panels, boost converter, inverter, induction motor, centrifugal pump and a storage tank. In this study, the output power of a PV solar cell is fully used by proposing the P&O algorithm, where it is used to follow a maximum power point tracking (MPPT) technique. The recommended system is designed, modeled and simulated on the MATLAB / Simulink platform. The efficiency of the proposed algorithm is observed with variable solar sunshine.
Design and simulation of stand alone integrated renewable energy system for r...eSAT Journals
Abstract
Present day guided weapon systems, especially tactical class missiles use RF seeker, for target tracking towards terminal engagement. The seeker system including its antenna assembly will be onboard the missile. Due to the missile trajectory corrections, the seeker antenna pointing to the target may get disturbed resulting in track loss. To avoid this track loss, it becomes necessary to stabilize the antenna system in two planes. The fundamental role of stabilization loop in seeker application is to precisely follow the angular rate of the target. In order to achieve this requirement, it is essential to highly isolate the gimbaled antenna from the missile body motion due to the maneuvering of target or low frequency vibration during flight. However, the isolation ratio and stability margin of stabilization loop adopting the gimbaled platform with both low stiffness and heavy inertia are limited by mechanical characteristic such as low resonance frequency and its high magnitude. The selection of proper feedback sensors, modeling of the total system are key features of this project. In the end, the performance and the stability of designed stabilization loop are demonstrated using simulation in both frequency and time domain. The Hardware for the system is under realization by the Industry. The whole scheme is simulated in MATLAB off-line for this project.
Keywords: Missile, RF seeker, Track loss, Stabilization loop, Angular Rate Command, Bore-Sight Error, Maneuvering and Gimbaled Platform.
Design and Modeling of Grid Connected Hybrid Renewable Energy Power GenerationIJERA Editor
This paper proposes a design and modeling of grid connected hybrid renewable energy power generation. The
energy system having a photo voltaic (PV) panel, Srg wind turbine and fuel cell (sofc) for continuous power
flow management. Fuel cells (storage & generating) are added to ensure uninterrupted power supply due to the
discontinuous nature of solar and wind resources. Renewable energy generated during times of plenty can be
stored for use during periods when sufficient electricity is not available. But storing this energy is a difficult
task: batteries and similar technologies perform well over short timescales, but over periods of weeks or months
a different approach is necessary. Energy storage in the form of hydrogen is one such possibility: excess
electricity is fed into an electrolyser to split water into its constituent parts, oxygen and hydrogen. The hydrogen
is then used in fuel cells to produce electricity when needed which will overcome the problem of storage. This
work is mainly concentrated on the design, analysis and modelling of Fuel cells and Analysis and modelling of
Switched Reluctance Generator (SRG) in the application of Wind Energy Generation and pv cell. Also an
effective approach is proposed in this thesis to ensure renewable energy diversity and effective utilization. The
pv cell, wind and fuel cell renewable energy system is digitally simulated using the MATLAB/SIMULINK
software environment and fully validated for efficient energy utilizations and enhanced interface power quality
under different operating conditions and load excursions
A Review on Design and Development of high Reliable Hybrid Energy Systems wit...IJPEDS-IAES
Hybrid Energy system is a combination of two or more different types of energy resources. Now a day this hybrid energy system plays key role in various remote area power applications. Hybrid energy system is more reliable than single energy system. This paper deals with high reliable hybrid energy system with solar, wind and micro hydro resources. The proposed hybrid system cable of multi mode operation and high reliable due to non communicated based controllers (Droop Characteristic Control) are used for optimal power sharing. Size of battery can be reduced because hydro used as back up source and Maximum power point Tracking also applied to solar and wind energy systems.
Simulation of generalized hybrid model for solar and wind power generationIJERA Editor
Due to urbanization, globalization and industrialization the demand for energy is rapidly increasing allows the world and India is not an exception. Out of all energies electrical energy is playing a major role in developed as well as developing countries. The energy is mostly produced by fossil fuels which are developing day his is to by day .they also produce lot of pollutants which totally damage the environment the alternative to this is to encourage renewable energy source. Now days the energy production at domestic level is becoming popular with the help of solar and wind energies . These technologies are widely used now days in the present paper an attempt has been made to simulate a generalized hybrid model including solar and wind.
Energy Storage Management in Grid Connected Solar Photovoltaic SystemIJERA Editor
The penetration of renewable sources in the power system network in the power system has been increasing in the recent years. One of the solutions being proposed to improve the reliability and performance of these systems is to integrate energy storage device into the power system network. This paper discusses the modeling of photo voltaic and status of the storage device such as lead acid battery for better energy management in the system. The energy management for the grid connected system was performed by the dynamic switching process.
Measurement and Analysis of Power in Hybrid Systemijeei-iaes
Application with renewable energy sources such as solar cell array, wind turbines, or fuel cells have increased significantly during the past decade. To obtain the clean energy, we are using the hybrid solar-wind power generation. Consumers prefer quality power from suppliers. The quality of power can be measured by using parameters such as voltage sag, harmonic and power factor. To obtain quality power we have different topologies. In our paper we present a new possible topology which improves power quality. This paper presents modeling analysis and design of a pulse width modulation voltage source inverter (PWM-VSI) to be connected between sources, which supplies energy from a hybrid solar wind energy system to the ac grid. The objective of this paper is to show that, with an adequate control, the converter not only can transfer the dc from hybrid solar wind energy system, but also can improve the power factor and quality power of electrical system. Whenever a disturbance occurs on load side, this disturbance can be minimized using open loop and closed loop control systems.
Presentation prepared for the Mindtree webinar on Trade Promotion Effectiveness. With the focus on trade promotion management to spur growth, sales teams need technologies to help analyze store and retail-specific data that is current(with minimal latency). This is not today’s reality. The average sales person today struggles to get data, and clarity of spend targets.
Modeling, Control and Power Management Strategy of a Grid connected Hybrid En...IJECEIAES
This paper presents the detailed modeling of various components of a grid connected hybrid energy system (HES) consisting of a photovoltaic (PV) system, a solid oxide fuel cell (SOFC), an electrolyzer and a hydrogen storage tank with a power flow controller. Also, a valve controlled by the proposed controller decides how much amount of fuel is consumed by fuel cell according to the load demand. In this paper fuel cell is used instead of battery bank because fuel cell is free from pollution. The control and power management strategies are also developed. When the PV power is sufficient then it can fulfill the load demand as well as feeds the extra power to the electrolyzer. By using the electrolyzer, the hydrogen is generated from the water and stored in storage tank and this hydrogen act as a fuel to SOFC. If the availability of the power from the PV system cannot fulfill the load demand, then the fuel cell fulfills the required load demand. The SOFC takes required amount of hydrogen as fuel, which is controlled by the PID controller through a valve. Effectiveness of this technology is verified by the help of computer simulations in MATLAB/SIMULINK environment under various loading conditions and promising results are obtained.
Modeling and Steady State Response Analysis of Interconnected Hybrid Renewable Energy Network with Embedded VSC - MTDC Transmission System for Secure and Efficient Power Delivery
Isolated Wind Hydro Hybrid Generation System with Battery StorageIJMER
In this paper, a new isolated wind- hydro hybrid generation system comprising one squirrel -cage induction generator (SCIG) driven by a variable-speed wind turbine and another synchronous generator driven by constant power hydro turbine feeding three phase four wire local loads is proposed. The system utilizes two back to back connected voltage-source converters (VSCs) with a battery energy storage system at their dc link. The main objective of the control algorithm for the VSC is to achieve control of the magnitude and the frequency of the load voltage. The proposed wind-hydro hybrid system has a capability of bidirectional active- and reactive-power flow, by which it controls the magnitude and the frequency of the load voltage. The proposed electromechanical system is modelled and simulated in MATLAB using Simulink.
Operation and Control of Grid Connected Hybrid AC/DC Microgrid using Various RESIAES-IJPEDS
This paper proposes a Hybrid AC/DC Microgrid in alliance with Photo Voltaic (PV) energy, Wind Energy and Proton Exchange Membrane (PEM) Fuel cells. Microgrids are becoming increasingly attractive to the researchers because of the less greenhouse gases, low running cost, and flexibility to operate in connection with utility grid. The Hybrid AC/DC Microgrid constitutes independent AC and DC subgrids, where all the corresponding sources and loads are connected to their respective buses and these buses are interfaced using an interfacing converter. The Hybrid AC/DC Microgrid increases system efficiency by reducing the multiple reverse conversions involved in conventional RES integration to grid. A Small Hybrid AC/DC Microgrid in grid connected mode was modeled and simulated in MATLAB- SIMULINK environment. The simulation results prove the stable operation considering the uncertainty of generations and loads.
Simulation of MPPT Algorithm Based Hybrid Wind-Solar-Fuel Cell Energy SystemIJMER
This paper presents a new system configuration of the front-end rectifier stage for a hybrid
wind/photovoltaic energy system. This configuration allows the two sources to supply the load
separately or simultaneously depending on the availability of the energy sources. The inherent nature of
this Cuk-SEPIC fused converter, additional input filters are not necessary to filter out high frequency
harmonics. Harmonic content is detrimental for the generator lifespan, heating issues, and efficiency.
The fused multiinput rectifier stage also allows Maximum Power Point Tracking (MPPT) to be used to
extract maximum power from the wind and sun when it is available. An adaptive MPPT algorithm will
be used for the wind system and a standard perturb and observe method will be used for the PV system.
Operational analysis of the proposed system will be discussed in this paper. Simulation results are given
to highlight the merits of the proposed circuit.
This paper discusses about a LabVIEW based controller for the hybrid renewable energy system operated AC-DC microgrid with the major objectives of: i) predicting the power generation potential of the solar–PV and wind generators ii) effective power management iii) load scheduling based on the available power with the renewable sources and iv) grid/islanding mode of operation of the microgrid. In order topredict the output power of wind generator and Solar-PV system, an artificial neural network is developed.The laboratory-scale model of three phase, 400 V, 10 kVA microgrid structure is developed at National Institute of Technology Calicut, India. The developed LabVIEW based controller has been tested successfully for a real-time load and source in the laboratory environment. Test results show that the designed controller is effectively managing the output powerof the primary energy sources under different scenarios.
Standalone photovoltaic array fed induction motor driven water pumping system IJECEIAES
Due to the absence of energy transmission lines connected to the water pumping sites in remote areas, problems related to the electrical power outages and the environmental degradation caused by fossil fuel. For this one of the most conceived solutions is the photovoltaic water pumping technology which has the advantage of being sustainable and respectful of the environment to supply water to rural areas. To ensure the need of water, especially for domestic use and small communities, in this article, the photovoltaic energy system for autonomous water pumping using the induction motor was presented, particularly adapted to the isolated regions. Pumping system consists of four photovoltaic (PV) panels, boost converter, inverter, induction motor, centrifugal pump and a storage tank. In this study, the output power of a PV solar cell is fully used by proposing the P&O algorithm, where it is used to follow a maximum power point tracking (MPPT) technique. The recommended system is designed, modeled and simulated on the MATLAB / Simulink platform. The efficiency of the proposed algorithm is observed with variable solar sunshine.
Design and simulation of stand alone integrated renewable energy system for r...eSAT Journals
Abstract
Present day guided weapon systems, especially tactical class missiles use RF seeker, for target tracking towards terminal engagement. The seeker system including its antenna assembly will be onboard the missile. Due to the missile trajectory corrections, the seeker antenna pointing to the target may get disturbed resulting in track loss. To avoid this track loss, it becomes necessary to stabilize the antenna system in two planes. The fundamental role of stabilization loop in seeker application is to precisely follow the angular rate of the target. In order to achieve this requirement, it is essential to highly isolate the gimbaled antenna from the missile body motion due to the maneuvering of target or low frequency vibration during flight. However, the isolation ratio and stability margin of stabilization loop adopting the gimbaled platform with both low stiffness and heavy inertia are limited by mechanical characteristic such as low resonance frequency and its high magnitude. The selection of proper feedback sensors, modeling of the total system are key features of this project. In the end, the performance and the stability of designed stabilization loop are demonstrated using simulation in both frequency and time domain. The Hardware for the system is under realization by the Industry. The whole scheme is simulated in MATLAB off-line for this project.
Keywords: Missile, RF seeker, Track loss, Stabilization loop, Angular Rate Command, Bore-Sight Error, Maneuvering and Gimbaled Platform.
Design and Modeling of Grid Connected Hybrid Renewable Energy Power GenerationIJERA Editor
This paper proposes a design and modeling of grid connected hybrid renewable energy power generation. The
energy system having a photo voltaic (PV) panel, Srg wind turbine and fuel cell (sofc) for continuous power
flow management. Fuel cells (storage & generating) are added to ensure uninterrupted power supply due to the
discontinuous nature of solar and wind resources. Renewable energy generated during times of plenty can be
stored for use during periods when sufficient electricity is not available. But storing this energy is a difficult
task: batteries and similar technologies perform well over short timescales, but over periods of weeks or months
a different approach is necessary. Energy storage in the form of hydrogen is one such possibility: excess
electricity is fed into an electrolyser to split water into its constituent parts, oxygen and hydrogen. The hydrogen
is then used in fuel cells to produce electricity when needed which will overcome the problem of storage. This
work is mainly concentrated on the design, analysis and modelling of Fuel cells and Analysis and modelling of
Switched Reluctance Generator (SRG) in the application of Wind Energy Generation and pv cell. Also an
effective approach is proposed in this thesis to ensure renewable energy diversity and effective utilization. The
pv cell, wind and fuel cell renewable energy system is digitally simulated using the MATLAB/SIMULINK
software environment and fully validated for efficient energy utilizations and enhanced interface power quality
under different operating conditions and load excursions
A Review on Design and Development of high Reliable Hybrid Energy Systems wit...IJPEDS-IAES
Hybrid Energy system is a combination of two or more different types of energy resources. Now a day this hybrid energy system plays key role in various remote area power applications. Hybrid energy system is more reliable than single energy system. This paper deals with high reliable hybrid energy system with solar, wind and micro hydro resources. The proposed hybrid system cable of multi mode operation and high reliable due to non communicated based controllers (Droop Characteristic Control) are used for optimal power sharing. Size of battery can be reduced because hydro used as back up source and Maximum power point Tracking also applied to solar and wind energy systems.
Simulation of generalized hybrid model for solar and wind power generationIJERA Editor
Due to urbanization, globalization and industrialization the demand for energy is rapidly increasing allows the world and India is not an exception. Out of all energies electrical energy is playing a major role in developed as well as developing countries. The energy is mostly produced by fossil fuels which are developing day his is to by day .they also produce lot of pollutants which totally damage the environment the alternative to this is to encourage renewable energy source. Now days the energy production at domestic level is becoming popular with the help of solar and wind energies . These technologies are widely used now days in the present paper an attempt has been made to simulate a generalized hybrid model including solar and wind.
Energy Storage Management in Grid Connected Solar Photovoltaic SystemIJERA Editor
The penetration of renewable sources in the power system network in the power system has been increasing in the recent years. One of the solutions being proposed to improve the reliability and performance of these systems is to integrate energy storage device into the power system network. This paper discusses the modeling of photo voltaic and status of the storage device such as lead acid battery for better energy management in the system. The energy management for the grid connected system was performed by the dynamic switching process.
Measurement and Analysis of Power in Hybrid Systemijeei-iaes
Application with renewable energy sources such as solar cell array, wind turbines, or fuel cells have increased significantly during the past decade. To obtain the clean energy, we are using the hybrid solar-wind power generation. Consumers prefer quality power from suppliers. The quality of power can be measured by using parameters such as voltage sag, harmonic and power factor. To obtain quality power we have different topologies. In our paper we present a new possible topology which improves power quality. This paper presents modeling analysis and design of a pulse width modulation voltage source inverter (PWM-VSI) to be connected between sources, which supplies energy from a hybrid solar wind energy system to the ac grid. The objective of this paper is to show that, with an adequate control, the converter not only can transfer the dc from hybrid solar wind energy system, but also can improve the power factor and quality power of electrical system. Whenever a disturbance occurs on load side, this disturbance can be minimized using open loop and closed loop control systems.
Presentation prepared for the Mindtree webinar on Trade Promotion Effectiveness. With the focus on trade promotion management to spur growth, sales teams need technologies to help analyze store and retail-specific data that is current(with minimal latency). This is not today’s reality. The average sales person today struggles to get data, and clarity of spend targets.
7 reasons why media productivity plans don't work as expectedPaola Furlanetto
. Why Media Productivity is still a company need
. 7 common mistakes in media productivity and how to fix it.
Including a short Introduction on the Multi Dimensions Media System.
and the Rising Stars / Evergreen / Sunset categories.
My books- Learning to Go https://gum.co/learn2go & The 30 Goals Challenge for Teachers http://routledge.com/books/details/9780415735346/
Resources- http://shellyterrell.com/halloween
La atención es un proceso cognoscitivo que nos permite seleccionar la información a la que queremos atender y nos ayuda a procesar los datos que queremos de entre todas las estimulaciones que recibimos.
NOTE: The videos in this presentation have not been enabled to play
“The tag is the soul of the Internet”, says Derrick de Kerckhove in The Augmented Mind. How can educators exploit the use of tagging content in a variety of mediums in order to help students practice these new literacies and understand the workings of the Web? In this session we’ll look at both practical and creative (or “meta”) tagging and explore ways to organize a course in Twitter, G+, Storify, Instagram, and Wordpress blogs. We’ll explore playful uses of tags to recontextualize, add commentary, or create art, poetry, and literature. The hashtag is a powerful device of the organization of knowledge, but it can be maximized for critical and divergent thinking.
*this is a presentation with hands-on activities. Please bring a mobile device and, if you wish, a laptop.
The negative impacts or side effects of a damper circuit insertion in an LCL passive filter utilized to filter DC/AC inverters output voltage is presented in this paper. For comparative study, this paper discusses two damping configurations, namely series and parallel damping, as well as the LCL filter without damping element. Four criteria are used to explore the impacts of the damper circuits, i.e. their total harmonic distortions (THDs), the output voltage amplitude, the output power and the power efficiency. Theoretically and emphirically shown by previous studies, the damper can indeed reduce the peak resonance frequency of the filter in its frequency response curve. However, in any circumstance, it can potentially reduce the inverters power and efficiency, voltage output amplitude, and cannot improve its THD reduction. The analysis results have shown that the side effects depends also on the load conditions, which are different for each damping circuit configuration.
Transformer BAT.12 PLTGU Priok is a power transformer which has an important role in distributing electrical power from PLTGU Priok to the load network. BAT 12 transformer which has been operating for a long time will certainly experience a decrease in standard and quality due to electrical, thermal, mechanical, chemical, and aging factors. One of the decreases in the standard and quality of the transformer is the decrease in the quality of the winding insulation. During the last two years of operation, there were several disturbances in the BAT. 12 PLTGU Priok transformer. Based on the Maximo 201819647 work order, there is a disturbance that can damage the isolation on the transformer. To determine the condition of the isolation quality and anticipate unexpected transformer breakdowns, it is necessary to test the transformer standard parameters. This test includes testing the insulation quality of the transformer windings. The Tangent Delta, Insulation Resistance and Dielectric Frekeuncy Respone test methods were carried out to determine the standard parameters of the dissipation factor, insulation resistance, polarity index, moisture content and oil conductivity. The test results are Tangent Delta of <0.5%, Oil conductivity of <6.7 pS / m, moisture content of <1.5%, HV / LV Insulation Resistance of 538 MΏ and polarity index of 2.76. The results of this test show that the transformer is still in good condition.
Frequency response analysis under faults in weak power systemsIJECEIAES
The renewable energy sources (RESs) projects are solutions with environmental benefits that are changing the traditional power system operation and concept. Transient stability analysis has opened new research trends to guarantee a secure operation high penetration. Problems such as frequency fluctuations, decoupling between generator angular speed, network frequency fluctuation and kinetic energy storing absence are the main non-conventional RESs penetration in power systems. This paper analyzes short-circuit influence on frequency response, focusing on weak distribution networks and isolated, to demonstrate relevance in frequency stability. A study case considered a generation outage and a load input to analyze frequency response. The paper compares frequency response during a generation outage with a short-circuit occurrence. In addition, modular value and angle generator terminal voltage affectation by electric arc and network ratio R⁄X, failure type influence in power delivered behavior, considering fault location, arc resistance and load. The arc resistance is defined as an added resistance that appears during failure and influences voltage modulus and angle value results showing that intermittent nonconventional RES participation can lead to frequency fluctuations. Results showed that arc resistance, type of failure, location and loadability determine the influence of frequency response factors in weak power systems.
Fuel Cell Impedance Model Parameters Optimization using a Genetic Algorithm Yayah Zakaria
The objective of this paper is the PEM fuel cell impedance model parameters identification. This work is a part of a larger work which is the diagnosis of the fuel cell which deals with the optimization and the parameters identification of the impedance complex model of the Nexa Ballard 1200 PEM fuel cell. The method used for the identification is a sample genetic algorithm and the proposed impedance model is based on electric parameters, which will be found from a sweeping of well determined frequency bands. In fact, the frequency spectrum is divided into bands according to the behavior of the fuel cell. So, this work is considered a first in the field of impedance spectroscopy So, this work is considered a first in the field of impedance spectroscopy. Indeed, the identification using genetic algorithm requires experimental measures of the fuel cell impedance to optimize and identify the impedance model parameters values. This method is characterized by a good precision compared to the numeric methods. The obtained results prove the effectiveness of this approach.
Megan gave a fascinating talk showcasing her work on network analysis of virtual water trade. We discussed water and food security in the context of population growth, economic development and climate change.
How to Make a Field invisible in Odoo 17Celine George
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1. Reliable Electrochemical Energy Storage for Alternative Energy Craig B. Arnold Department of Mechanical and Aerospace Engineering Princeton Institute for Science and Technology of Materials Princeton University 2500 m
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6. Case Study: Wind Power P. Denholm, G. L. Kulcinski, and T. Holloway, "Emissions and energy efficiency assessment of baseload wind energy systems," Environmental Science and Technology , vol. 39, pp. 1903-1911, 2005. Fluctuations occur over many different time periods
9. Charging versus Discharging We all like to think about batteries like cups of coffee. We simply fill it up until it is filled and empty it out until it is empty But in reality, batteries are not that simple the rate matters
17. Mechanical Degradation Much work has been done looking at mechanical degradation to electrodes after electrochemically cycling cracking, delamination, etc. However, these types of studies typically ignore effects to the rest of the system Physical constraints can lead to elevated stress states throughout the battery Stress source Electrode Stress State Separator Stress state Electrode Expansion Tensile Compressive SEI Formation Compressive/Neutral Compressive External Compression Compressive Compressive External Bending Tensile/compressive Tensile/compressive
18. Separator Compression Regardless of most internal or external sources, the separator will experience compressive stress But how large is the stress ? Also notice that during rest step, the stress begins to decline J. Cannarella and CBA, in preparation Li + pouch cell (LiCoO 2 cathode) Cycle electrochemically while directly measuring the stress of the system Max stress is 1.3 MPa Average pinch stress for adult is ~1 MPa Mathiowetz et al., Arch Phys Med Rehabil , 66, p.69 (1985)
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20. SEM Images of Compressed Battery Unstressed Stressed Electrodes are unchanged, most deformation occurs in separator 30 MPa for 3 hours This is expected as the polymer separator is significantly weaker than the electrode material
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23. Creep Strain C. Peabody and CBA, in preparation As applied stress is increased the total permanent strain continues to increases
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25. Mechanism of Relaxation 0 MPa 10 MPa 30 MPa Viscoelastic creep causes pore closure in the polymer separator A 30MPa compressive stress for 3 hours decreases pore volume by almost 60% C. Peabody and C.B. Arnold, J. Power Sources 196, 8147 (2011) Pore volume decrease appears linear with respect to permanent strain
26. EIS Characterization of Separators Pore closure impedes ion transport through the separator C. Peabody and C.B. Arnold, J. Power Sources 196, 8147 (2011) Permanent strains as small as 10% can significantly reduce the capacity by a factor 2-3
27. Other Separators Higher porosity corresponds to larger creep strains at same stress state Similar effects occur for other separator materials Composition Porosity (%) Avg Pore Diam ( μ m) Thickness ( μ m) 2320 PP/PE/PP 39 0.027 20 2340 PP/PE/PP 45 0.035 40 3501 PP 55 0.064 25
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29. Electrochemical Performance The electrochemical effects of stress induced pore closure in the separator manifest as capacity fade C. Peabody and C.B. Arnold, J. Power Sources 196, 8147 (2011) Cycle separator in t-cell using commercial cathode and Li metal anode Charge/Discharge current constant 0.5 mA
30. Capacity Fade As a function of pore volume, we see a linear decrease in capacity The discharge capacity decreases with permanent strain As permanent strain reaches ~15%, the capacity of the cell has decreased by a factor of 2
31. Relevance Are these values relevant or way out of the realm of a real system ? In a typical Li + ion battery the electrodes may expand up to 10% Since the electrodes are typically 2-3 times thicker than the separator, such expansion if totally accommodated by the separator, could lead to strain values as high as 40-50 % They are very relevant Consider: Mechanical stress on the separator can be an important factor in battery design e.g. if T electrodes = 80, T sep = 20 T electrodes = 8 Then sep = 40% !
36. But in the 1600’s, scientists did not really know much about electricity or how to use it. The spark generators were mostly used by scientists to study the nature of the sparks In 1745, scientists (Musschenbroek and Cunaeus) noticed that one could “charge” up a glass filled with water and get a shock by touching a metal nail Shortly thereafter, this was simplified to just metal foil wrapped around the inside and outside of a jar with a chain connecting the inner layer. Leyden Jar We know these devices as capacitors, but they work by storing charge ELECTROSTATICALLY
37. Although they still didn’t know all that much about electricity, they now had methods of storing and generating electricity, but it was still a research tool (and a parlor trick) In fact, this enabled many important experiments of the time 1746: Nollet assembled a line of 200 monks each holding the end of a wire to test if electricity can travel faster than human communication. Without warning he connected a Leyden Jar to the ends … But Cavendish did not publish all that much and these discoveries were rediscovered years later by Faraday, Ohm, Coulomb, Maxwell 1747-1753 Cavendish used Leyden Jars to discover many of the fundamental physics laws of electricity Inverse square law for force, electric potential, capacitance, resistance
38. 1752: Ben Franklin and his famous kite experiment Showed that lightening is the same as electricity stored in Leyden Jar Franklin’s other main contributions to the field include the concept of current as the flow of positive charges, and the term battery We later found out he was very wrong, but unfortunately it was too late. This is why current goes in the opposite direction of electron flow Two disadvantages of the Leyden Jar are that it doesn’t store charge all that long (This is true in general for electrostatic storage) and it doesn’t store all that much energy
39. 1786: Galvani’s famous experiments on frog legs He took two dissimilar metals (Zn, Cu) and touched them to the ends of a dead frog’s leg Surprisingly, the leg moved and Galvani attributed this to bioelectricity
40. But Volta did not believe that the electricity came from the frog. He believed the electricity came from the metals In 1799, he showed that by combining different metals that are separated by a salt or acidic solution it was possible to generate electricity VOLTA PILE First commercially available battery An enabling techno-logy for the telegraph Side note: Galvani died one year earlier and never knowing the answer
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42. Separate reactions into half-cells Salt bridge: allows ions to move between cells Oxidation occurs at anode Material gives up electrons i.e. Zn Zn +2 + 2 e - Reduction occurs at cathode Material takes in electrons i.e. Cu +2 + 2e - Cu Voltaic or Galvanic Cells
43. M M n+ + ne - Oxidation Reduction M n+ + e - M (n-1)+ Oxidation is loss of electrons Reduction gains electrons Electrochemistry: chemical reactions require charge transfer This occurs through redox reactions Oxidation occurs at the anode anodic reaction Reduction occurs at the cathode cathodic reaction Both need to happen… electron is generated at the anode and must be consumed at the cathode so net charge is conserved in overall process Ions dissolve into solution Ions deposited from solution These are called Half-Cell reactions We need a salt bridge to complete the circuit so that the charge remains balanced otherwise, the charge would build up and the battery would stop working
44. In the process of oxidation and reduction, energy is converted from chemical into electrical i.e. Electrons are free to run through the circuit and do work Voltage of the cell is determined by the oxidized and reduced species and related to the change in free energy But they must go through the external wires Can think of this as analogous to water flowing downhill where the voltage is the height of the hill Zn can lower its energy by giving up electrons and dissolving into solution Cu + can lower its energy by capturing electron and ‘plating’ out on electrode In previous example, Zn Zn +2 + 2 e - Cu +2 + 2e - Cu +0.763 V +0.337 V 1.10 V
45. The important thing here is that every material has a slightly different potential
46. Just because a reaction is energetically favorable, that doesn’t mean we know how fast it will occur. The rate depends on kinetics It’s got to depend on: Temperature Voltage Concentration or pH Let’s consider a single electrode of Zn We know that oxidation and reduction can occur according to Zn Zn 2+ + 2 e - Furthermore, we know that if this is in equilibrium, then the forward and back reactions must be occurring at the same rate Lets define a current density i = I/A
47. Then, i f = i b = i o Where i o is called the exchange current density , sometimes denoted i e If we apply a voltage to this electrode, we will shift the reaction one direction or the other i f – i b = i 0 This condition can be described by the Butler-Volmer equation Where a and c are called the anodic and cathodic transfer coefficents s is called the surface overpotential or polarization s = V-V 0 * This expression for the B-V equation assumes a one electron process. Typically it is safe to use this equation since most reactions involving multiple electrons also involve multiple intermediary steps which involve a single electron and for current, we only have to worry about the slowest reaction. The details of this is way beyond the scope of this introductory course. When we don’t know, we usually assume a and c ~ 0.5 The exchange current tells us how fast a reaction can occur There are other prefactors that I have omitted
48. We notice the similarity of this equation to that for diffusion Also, note the sign convention that the forward current direction denotes an anodic reaction i.e. i > 0 oxidation is occurring (corrosion) i < 0, reduction is occurring (deposition) a = c = 0.5 a > c
49. Overpotential is a term that tells us how far from equilibrium we are Activation Overpotential Tafel (1905) observed: =a+b log i If we do some math on the B-V equation, we can see where this comes from Consider larger overpotentials so that one term dominates the B-V equation (lets choose anodic term) It’s a driving force for transport (just like chemical potential) So we can interpret the B-V equation as telling us the amount of current we get from a reaction given a certain electrode potential
50. So, we can plot this in a different way to find , i o , and V 0 Rearranging, we find or If we extrapolate the linear regime for both anodic and cathodic, the intersection will be at the equilibrium voltage and exchange current density Tafel Plot Voltage (V) Ln | i | (mA/cm 2 ) V 0 I o anodic cathodic RT/ a F RT/ c F
51. Other Overpotentials In reality, the Tafel equations are only valid in a small regime of potential At potentials close to the equilibrium potential, the slope decreases as reverse reactions become important At potentials much higher, the current becomes limited as the transport properties in the electrolyte limit the reaction Concentration overpotential The limiting current depends on the concentration in solution and could be increased significantly by mixing electrolyte
52. Fig 17.5W from Callister So depending on the overpotential, we may need to take concentration into account Also, don’t forget about resistive losses in the system as well
53. Electrochemical Energy Storage Batteries are a compact method of converting chemical energy into electrical energy Other methods, fuel cell, photovoltaic cell, electrochemical capacitors etc. All work the same, but the details are different C-rate charging/discharging rate, 1C is current needed to discharge in 1 hour Anode (Oxidation): Zn + 2 OH - Zn(OH) 2 + 2e - E = 1.25 V Ag 2 O + H 2 O + 2e - 2 Ag + 2 OH - E = 0.34 V Cathode (Reduction): e - e - e - e - e - e - Anode Cathode Electrolyte/Separator Current Collectors Primary : Non-rechargeable Secondary : rechargeable Voltage Potential difference between anode and cathode. Related to energy of reactions Capacity amount of charge stored (usually given per unit mass or volume)
54. So this raises a potential problem with the Volta Pile If Zn is the anode and H is the cathode, there is an evolution of hydrogen gas that could passivate the electrode or generate a large resistance to flow Solution is to use a wet cell that has the proper ions around (1836) Daniel Cell: Cu/Zn in sulfate solutions (1859) Plante: Pb/PbSO 4 cell Wet cells have an obvious disadvantage for transport, but they do work well
55. But actually, a wet cell battery may have existed well before Volta Archeologists found this clay pot in the Baghdad area in the 1930’s Carbon dating places it ~250 BC How does this work?
56. Leclanche in 1866 developed another kind of wet cell that had a better shelf life and was less reactive with the environment This battery was constructed with Zn as the anode and MnO 2 + C as the cathode The cathode was mixed into a paste and placed in a porous pot The Zn anode was immersed in a chloride electrolyte Very popular with the new Telegraph !!
59. Battery Types Battery chemistry has not changed much since 1800’s Leclanché Alkaline Silver-Oxide Rechargeable Alkaline 1866, 1888 1949 1950 1978 Zn-MnO 2 Zn-MnO 2 Zn-Ag 2 O Zn-MnO 2 Lead-acid 1859 Pb-PbSO 4 Ni- based NiCad Metal Hydride 1899 1990 Cd-NiOOH MH-NiOOH Li- based Lithium-Iodine Lithium ion Plastic/Polymer 1968 1991 1995 Li-I 2 Li-LiCoO 2 Li-LiCoO 2
60. How does a Li-ion battery work? Li ions intercalate into the crystal structure of the electrode materials But Li is very reactive (high V) which causes side reactions and passivation layers (solid electrolyte interphase) Critical to the proper functioning of these cells More advanced topic
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62. Impedance Matching So faced with all these choices, how do we choose an appropriate power source? The optimal power transfer to the load will occur when the impedance (resistance) is equal to the internal resistance Can derive this from Ohm’s laws However, we would not typically run a battery at this current as it would heat up too much
63. Ragone relation Energy density Energy per unit area/volume Specific Energy Energy per unit mass Other issues such as total weight, size, voltage, environmental concerns can limit our selection process In general, electrochemical systems always show the characteristically downward curved plots High power Low energy High energy Low power One might think that it is best to just push the limits of energy or power http://www.powerstream.comz/ragone.gif
64. Rate effects Another major factor in optimizing energy storage is the rate at which the energy is needed As with all batteries, there is a decrease in capacity (efficiency) as the power is increased But many application for batteries do not require extended periods of high power draw Energy demands differ from application to application Main limiting factor is rate of ion movement across electrolyte Duracell ‘D’ cell
65. Although standard specs can be reported, there are a variety of important issues that ultimately affect the lifetime and performance of a battery system for a desired application Current Drain: Different batteries respond differently to current In general, as current is increased, the available voltage and capacity decrease Peukert’s equation: I n x t = C I is current in A t is time in hr C is rated capacity Modified Peukert’s law But since C depends on rate, one must correct for this Where H is the hours for the rated capacity Handbook of Batteries 3e, Eds Linden and Reddy Rate effects
66. Different chemistries will have different voltages and different characteristic discharge curves Appropriate choice will depend on application limitations For instance, Silver Oxide batteries have a very flat discharge at 1.5 volts compared to Li-ion batteries with a sloping curve around 3 V Cut-off voltage of the device is an important parameter as it will determine the actual capacity that can be used Handbook of Batteries 3e, Eds Linden and Reddy Discharge Characteristics
67. Batteries operated in pulsed applications will last longer than constant discharge at same current During rest time, battery recovers voltage more of the theoretical capacity can be used Factors such as maximum current and duty cycle will have a profound effect on this issue Pulsing between high and low current (e.g. transmit/receive operations) will have a similar effect voltage will oscillate Voltage response to pulse will vary with chemistry Alkaline Zn-C High current pulsed can lead to catastrophic failure Handbook of Batteries 3e, Eds Linden and Reddy Pulsed Discharges
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69. An ultracapacitor has properties of both battery and capacitor It has a high power density and can be cycled like a capacitor But it also has a significant energy density like a battery Different Flavors: carbon, transition metal oxides Ionic conduction in liquid or solid-state electrolyte Electronically conductive electrodes Electrochemical capacitors Supercapacitors pseudocapacitors First ultracapacitor was patented in 1957 using porous carbon electrodes Require high surface area electrodes to achieve large capacitance Supercapacitors Double Layer: Charge stored in double layer at interface between electrolyte and electrode Pseudocapacitance: Faradaic charge storage at electrode surface ultracapacitors Capacitors Batteries Electrode Electrode Electrolyte
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Editor's Notes
Thanks for coming everyone. My name is Craig Arnold and I am happy to be here today to chat with you about reliable electrochemical energy for alternative energy. I’m not your usual CMI person as my background is in materials science. My group primarily studies the kinetics and mechanics of materials processing for a variety of applications. One such application is in energy storage. This is a different type of storage than we normally discuss within the confines of CMI, and is a recent seed program that we started. In the next few minutes, I want to give you a little background on the energy storage situation and focus particularly on electrochemical methods for improving the lifetime of batteries and capacitors in energy generating systems.
Why should we care about energy storage?
So if Energy storage is important and we understand the various technologies, why not just invent a giant energy storage device that solves all our problems? Portable vs. Stationary Required time range Usage profile
In certain environments, the zn would much rather give up electrons and dissolve into the solution than stay as a metal
Conceptionally, a mesoscale microbattery is no different than a large scale battery. In all cases, energy stored as chemical energy is converted to electrical energy through oxidation and reduction reactions. The first example of such a device was built by Volta in 1800 demonstrating the ability to generate electrical current. His device known as a Volta pile since it is basically a pile of alternating zn, ag and pasteboard disks. As we have a little better understanding of chemical reactions today than Volta in 1800, we can generalize the volta pile by noting that all electrochemical energy conversion devices contain the 3 major components, Anode, Cathode, and electrolyte/separator. The electrons for the external load circuit are generated by the oxidation of the anode material. In the case of a Ag-Zn battery, this is Zn that gets oxidized into Zn hydroxide. The electrons go through the load and recombine with the cathode material to reduce it giving off ions into the electrolyte. In this example, silver oxide is reduced to silver metal with hydroxide ions given into the electrolyte that is a highly basic solution. The ions diffuse through the electrolyte thereby completing the circuit. The separator prevents the anode and cathode from shorting through the battery itself. Of course, in order to connect the battery to the outside world, metal current collectors are needed at both the anode and cathode. For the most part, battery chemistries remained unchanged until recent times with the use of high capacity lithium in batteries. To improve battery performance, typically materials are added to the active material. for instance, since silver oxide is not a very good electron conductor, carbon is added to improve the electrical conductivity. Other additives decrease the formation of gases or self discharge of the battery. In the picture on the bottom, we can see all these components in a modern button cell.
Lead-acid Gaston Plante lithium batteries needed non-aqueous electrolytes in order to work There’s room for novel advances in
An ultracapacitor has properties similar to both batteries and capacitors but lies somewhere in between on the spectrum of energy storage devices. The device is constructed by sandwiching an ionically conductive electrolyte between two electronically conductive electrodes. We still have an anode and cathode, but in the case of a symmetric device, both of these are the same material. Like a capacitor, an ultracapacitor has the ability to very rapidly discharge its energy leading to a high power density. However like a battery, it has the ability to store a large amount of energy in the charge state of the active materials. So in the most basic manner, we can think of an ultracapacitor as a battery with a high discharge rate. These devices are typically used for load leveling and applications where a short burst of power is needed. Ultracapacitors go by other aliases such as electrochemical capacitors, supercapacitors, or pseudocapacitors. These types of devices come in different flavors that are distinguished by the mechanism for charge storage in the system. The simplest form is the double-layer effect that is similar to a typical capacitor. In these cases, the charge is stored in the double layer at the interface between the electrode and electrolyte, but a very high surface area leads to the large amounts of charge storage in the system. The other flavor stores charge in a pseudocapacitance effect. In this case, there is an actual faradaic charge transfer at the surface of the electrode material itself which can store lots of charge. This is similar to the redox reactions that take place in a regular battery. In truth, almost any material exhibits a combination of these effects with one dominating the overall capacitance of thematerial Our challenge is to produce these anodes, cathodes, and separators/electrolytes without harming the physical or chemical properties of the materials and maintain the structure necessary for an electrochemical energy storage device. Furthermore, we must restrict the material in all 3 dimensions.