Your SlideShare is downloading. ×
Battery technology for electric cars
Battery technology for electric cars
Battery technology for electric cars
Battery technology for electric cars
Battery technology for electric cars
Battery technology for electric cars
Battery technology for electric cars
Battery technology for electric cars
Battery technology for electric cars
Upcoming SlideShare
Loading in...5
×

Thanks for flagging this SlideShare!

Oops! An error has occurred.

×
Saving this for later? Get the SlideShare app to save on your phone or tablet. Read anywhere, anytime – even offline.
Text the download link to your phone
Standard text messaging rates apply

Battery technology for electric cars

335

Published on

Intereste

Intereste

Published in: Automotive, Technology, Business
0 Comments
0 Likes
Statistics
Notes
  • Be the first to comment

  • Be the first to like this

No Downloads
Views
Total Views
335
On Slideshare
0
From Embeds
0
Number of Embeds
0
Actions
Shares
0
Downloads
8
Comments
0
Likes
0
Embeds 0
No embeds

Report content
Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
No notes for slide

Transcript

  1. Battery technology for electric cars by Jeremy Horne, Ph.D.Before exploring what may lie in store for battery technology in electric vehicles,both all-electric and hybrids, we should review what makes up a battery in the firstplace. At that point we can begin understand the potentials and limitations ofelectron storage as a source of energy for propelling ourselves down the road.A battery simply is device that stores electrical charges based on the chemistryused in the materials making it up. The difference in electrical potential (the numberof electrons in one substance) between two substances determines how muchelectricity there is. Place your tongue between two coins made of different metals,such as one made from copper and the other aluminum, and allow the two coins totouch. You will feel a slight tingle and an acid taste. This is a simple battery, andwhat you feel are electrons flowing from the nickel to the penny. Two metals,commonly immersed in an acidic liquid will act as attraction points, or electrodes,for charged particles, negative or positive. When a device or electrical resistanceconnects the two electrodes current, or electrons, flow. The Table of PeriodicElements is the basis for calculating electrical potential in materials. The principle ofdetecting current is rather ancient.About the year of 1936 in the village of Khuyut Rabboua, near Baghdad, Iraq wasdiscovered a three piece set of objects consisting of a clay pot with a stopper, acoiled up sheet of cooper inside, and an iron rod that fit in the middle of the roll. In1938, these artifacts came to the attention of Wilhelm König, the German directorof the National Museum of Iraq, they being housed right in the same museum! Theyhave assumed the appellation of “Baghdad battery”. König thought that the artifacts------------------------------------------------------------------------------------------------------------------- ---------- IQPC GmbH | Friedrichstr. 94 | D-10117 Berlin, Germany t: +49 (0) 30 2091 3330 | f: +49 (0) 30 2091 3263 | e: eq@iqpc.de | w: www.iqpc.de Visit IQPC for a portfolio of topic-related events, congresses, seminars and conferences: www.iqpc.de
  2. dated to the Parthian period (between 250 BCE and 224 CE), and that date hasntbeen substantially challenged since [1]. While the assemblage could theoretically beused in conjunction with an electrolyte to for copper plating or to get a tinglingsensation as in medical therapy or religious ceremonies, the actual ability to do hasshown to be marginal. Nevertheless, it is intriguing to consider that this may havebeen the first battery.Alessandro Volta in 1792 invented a device, an electrochemical cell (called a “pile”)that could store charges, and in 1800 he placed a number of these in series to makewhat could truly be called the first battery, a means of storing electricity using thechemical properties of materials. The word “pile” means battery in Europe. It can beargued, however, that the Leyden jar, invented independently by German clericEwald Georg von Kleist on 11 October 1745 and by Dutch scientist Pieter vanMusschenbroek of Leiden (Leyden) in 1745–1746 was the first battery, inasmuch asit, too could store charges. It has been known since classical Greek times thatstroking an amber rod with cloth will produce sparks, and electrostatic generatorswere built to do this mechanically. In fact, "elektron"(ηλεκτρον) is Greek for amber,and one easily can discern the word being the root word for our present day“electricity”. Even at the beginning of the 20th century Leyden jars were usedextensively in early wireless telegraphy (spark transmitter) and in equipment formedical therapy. Now, capacitors are used.Electrostatic generators were created in the 18th century, often consisting a largewheel against which were placed soft substances, such as cloth, to “scrape”electrons off the wheel. By allowing this current from the generator to the Leydenjar, electrons would flow to electric plates to main until drawn off by coming intocontact with an object. Today, this principle is known as capacitance, and one needonly open up just about any electronic device to see the characteristic barrel-shaped------------------------------------------------------------------------------------------------------------------- ---------- IQPC GmbH | Friedrichstr. 94 | D-10117 Berlin, Germany t: +49 (0) 30 2091 3330 | f: +49 (0) 30 2091 3263 | e: eq@iqpc.de | w: www.iqpc.de Visit IQPC for a portfolio of topic-related events, congresses, seminars and conferences: www.iqpc.de
  3. objects that store electricity and marked often in microfarads (µf). Typically, theyare made of aluminum sheets interleaved with an insulator and coiled to result inthe drum-like shape. There have been numerous designs for the Leyden jar, withmost being constructed of a metallic foil coating both the inner and out part of abottles wall, with the two pieces never touching each other. A conductor, such as achain, leads from the center of an insulated cap to the bottom of the jar andtouches the inner foil. The exiting chain has a contact point to which is touched thedischarge point of the electrostatic generator. The outer foil is grounded. When theouter and inner foil meet, there is a spark, hence electricity. Water filled Leyden jar (left) and 1914 physics book drawing (right) [2]Battery construction and operationThere are two battery types, primary, or disposable, and secondary, orrechargeable. The first are ubiquitous in unsophisticated devices like flashlights,used one time, and are less expensive per battery. The second is the focal point ofour interest, as they can be used numerous times after recharges, but they areconsiderably more costly. Numerous constructions and materials exist, nickel-metalhydride battery being used in most electric cars in 2009 [3], but, for our discussion,------------------------------------------------------------------------------------------------------------------- ---------- IQPC GmbH | Friedrichstr. 94 | D-10117 Berlin, Germany t: +49 (0) 30 2091 3330 | f: +49 (0) 30 2091 3263 | e: eq@iqpc.de | w: www.iqpc.de Visit IQPC for a portfolio of topic-related events, congresses, seminars and conferences: www.iqpc.de
  4. we consider the lithium-ion battery, as the former are being phased out. They arethe same type of batteries used in laptop computers, cordless tools, and manyelectronic devices.The basic operation occurs in discharge by ionized lithium flowing from the anode(positive terminal made from lithium embedded in carbon-based materials, usuallygraphite) to the electrolyte (composed of lithium salts in organic solvents) through aplastic separator (a micro porous membrane) and then to the cathode (negativeterminal made of lithium metal oxide or phosphate). Concurrently, the anodereleases electrons to an electric circuit connected to the battery and is oxidized.Upon re-charging, the process is reversed, with the lithium ions traveling from thecathode to the anode via the separator and electrolyte. The electrolyte can beliquid, a gel, or solid polymer, with the greatest ease of ion flow being in the liquidthen the gel, and lastly, the polymer. Movement of charges in lithium ion battery [4]------------------------------------------------------------------------------------------------------------------- ---------- IQPC GmbH | Friedrichstr. 94 | D-10117 Berlin, Germany t: +49 (0) 30 2091 3330 | f: +49 (0) 30 2091 3263 | e: eq@iqpc.de | w: www.iqpc.de Visit IQPC for a portfolio of topic-related events, congresses, seminars and conferences: www.iqpc.de
  5. Energy usage varies with the type of vehicle, hybrid electric (HEV), plug-in hybridelectric (PHEV), and straight electric (EV). HEVs use the battery for assisting themotor, while the PHEVs start out with the battery being the sole source of powerand afterwards only as a power assist, and the latter is the only source of power. Inall cases, a lithium-ion battery is used. The first two require only a shallow cycle(the battery not being fully charged) and the EVs a deep cycle (where you fullycharge and can drain without damage, marine batteries being an example). Battery performance for electric vehicle types [5]There are four parameters that have been used to assess the appropriate batteryfor an application, these being energy/weight ratio, energy/volume ratio, power toweight ratio, and the cost in watt-hours (in the U.S., that being the watt-hours perdollar). While lead-acid produces more energy per dollar, it still is not suitable forEVs because of its power per unit weight and energy per volume in watt-hours, asthe following chart illustrates.------------------------------------------------------------------------------------------------------------------- ---------- IQPC GmbH | Friedrichstr. 94 | D-10117 Berlin, Germany t: +49 (0) 30 2091 3330 | f: +49 (0) 30 2091 3263 | e: eq@iqpc.de | w: www.iqpc.de Visit IQPC for a portfolio of topic-related events, congresses, seminars and conferences: www.iqpc.de
  6. Energy/weig Energy/volu Power/wei Energy/US Battery ht me ght $ Type Watt- watt- watt/Kg watt-hr/$ hours/Kg hours/L Lead-acid 30-40 60-75 180 4-10 NIckel-Zinc 60-70 170 900 2-3 Lithium-Ion 160 270 1800 3-5 Lithium- 130-200 300 to 2800 3-5 Polymer Lead polymer batteries are used in hybrid vehicles. [6]Two other values often are considered, the self-discharge rate, meaning chargedissipation with age, and the cycle life of the batteries, or how many times thebatteries can undergo a deep or complete discharge and still be re-charged [7].Problems associated with lithium ion batteriesIn terms of efficiency energy per unit mass a lithium ion battery is much lower thanfor other power sources, such as petroleum. Weight is a major problem, the metalsused to create the power being the major factor. Most of the weight of the vehicle isthe battery (average of 333 kg – 2009) [8] and motor, of course, most of theenergy expended in powering that vehicle is just to transport the battery itself! Aconventional mid-sized car, by contrast has the power train (v-6 engine – 181 kg -and transmission) not even half the vehicle weight. Perhaps the most limiting factoris the range; the average electric car is lucky be able to get 150 range [9]. Thatrange is extended only in hybrids, such as a gas/natural gas/electric car. There areenvironmental costs, not the least of which is the energy to produce them, from the------------------------------------------------------------------------------------------------------------------- ---------- IQPC GmbH | Friedrichstr. 94 | D-10117 Berlin, Germany t: +49 (0) 30 2091 3330 | f: +49 (0) 30 2091 3263 | e: eq@iqpc.de | w: www.iqpc.de Visit IQPC for a portfolio of topic-related events, congresses, seminars and conferences: www.iqpc.de
  7. mining of the minerals, energy required in their manufacturing, and disposal.Recycling is not easy, as there are not many usable components.Lithium-ion batteries, while having good power density, have short cycle lives, withthe battery degrading with each recharge. Even sitting on a shelf the batterydegrades. Besides the cathode being somewhat toxic, there is a fire risk if thebattery is punctured or not charged properly. Lithium-ion batteries dont like coldconditions, and in very cold places, inefficient heating devices have to be used justto keep the battery going.A central problem with lithium-ion batteries is their loss of capacity to storeelectricity over time. A minor scandal has erupted over Apples sale of the veryexpensive iPods amounting to several hundreds of dollars with their failing a fewshort years because of batterys inability to be recharged [10]. Laptops have thesame deficiency, and it is not inexpensive to replace this power source. Scientistshave investigated the problem and discovered that the lithium ions carrying theelectric charges were not only diminished but has accumulated on the anode, with alessened concentration of lithium, as opposed to new batteries. One cannot reversethis problem and only can dispose of the battery. In addition, the nanostructures ofthe battery coarsen over time [11]. Want to learn more about current and future developments in Electric Vehicles? Visit our Download Center for more articles, whitepapers and interviews: http://bit.ly/ev-articles------------------------------------------------------------------------------------------------------------------- ---------- IQPC GmbH | Friedrichstr. 94 | D-10117 Berlin, Germany t: +49 (0) 30 2091 3330 | f: +49 (0) 30 2091 3263 | e: eq@iqpc.de | w: www.iqpc.de Visit IQPC for a portfolio of topic-related events, congresses, seminars and conferences: www.iqpc.de
  8. References (Subject is indicated by URL – accessed 7 October 2011)[1] http://en.wikipedia.org/wiki/Baghdad_Battery[2] http://en.wikipedia.org/wiki/Leyden_jar[3] http://gigaom.com/cleantech/the-future-of-electric-vehicle-batteries-lithium-ion-china/[4] Lithium-ion Batteries for Electric Vehicles: The U.S. Value Chain, p. 15,https://docs.google.com/viewer?url=http://www.cggc.duke.edu/pdfs/Lithium-Ion_Batteries_10-5-10.pdf&embedded=true&chrome=true[5] Ibid., p. 12[6] http://www.allaboutbatteries.com/electric_cars.html[7] http://www.allaboutbatteries.com/electric_cars.html[8] DOE - http://www.whitehouse.gov/files/documents/Battery-and-Electric-Vehicle-Report-FINAL.pdf[9] http://www1.eere.energy.gov/vehiclesandfuels/avta/light_duty/fsev/fsev_batteries.html[10] http://en.wikipedia.org/wiki/IPod_Mini[11] http://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries[12] http://www.whitehouse.gov/files/documents/Battery-and-Electric-Vehicle-Report-FINAL.pdf[13] http://web.mit.edu/newsoffice/2011/flow-batteries-0606.html[14] http://www.nrel.gov/vehiclesandfuels/energystorage/ultracapacitors.html[15] http://www.nrel.gov/vehiclesandfuels/energystorage/ultracapacitors.html[16] http://arpa-e.energy.gov/ProgramsProjects/BEEST/TheAllElectronBatteryaquantumleapforwardi.aspx[17] http://pubs.acs.org/cen/science/88/8847sci1.html, http://www.physorg.com/news176646131.html[18] http://micro.magnet.fsu.edu/electromag/electricity/batteries/metalair.html[19] http://www.ict.fraunhofer.de/EN/coreco/AE/Batt_tech/Bat_dev/index.jspResources (Subject is indicated by URL – accessed 7 October 2011)http://www.sweethaven02.com/ModElec/electrical01/Lesson0402.pdfhttp://en.wikipedia.org/wiki/History_of_the_batteryhttp://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries------------------------------------------------------------------------------------------------------------------- ---------- IQPC GmbH | Friedrichstr. 94 | D-10117 Berlin, Germany t: +49 (0) 30 2091 3330 | f: +49 (0) 30 2091 3263 | e: eq@iqpc.de | w: www.iqpc.de Visit IQPC for a portfolio of topic-related events, congresses, seminars and conferences: www.iqpc.de
  9. http://www.youtube.com/watch?v=KlI1duF4K9ohttp://en.wikipedia.org/wiki/Leyden_jarBatteries for Electric Cars - http://www.bcg.com/documents/file36615.pdfhttp://en.wikipedia.org/wiki/Electric_vehicle_batteryhttp://en.wikipedia.org/wiki/Piezoelectricity#Mathematical_descriptionhttp://inhabitat.com/new-crash-proof-electric-vehicle-battery-can-be-mass-produced/http://www1.eere.energy.gov/vehiclesandfuels/avta/light_duty/fsev/fsev_batteries.htmlhttp://spinnovation.com/sn/Batteries/Batteries_and_Ultracapacitors_for_Electric_Hybrid_and_Fuel_Cell_Vehicles.pdfhttp://en.wikipedia.org/wiki/Electric_vehicle_batteryhttp://www.bcg.com/documents/file36615.pdf” -http://www.iqpc.com/Event.aspx?id=473352------------------------------------------------------------------------------------------------------------------- ---------- IQPC GmbH | Friedrichstr. 94 | D-10117 Berlin, Germany t: +49 (0) 30 2091 3330 | f: +49 (0) 30 2091 3263 | e: eq@iqpc.de | w: www.iqpc.de Visit IQPC for a portfolio of topic-related events, congresses, seminars and conferences: www.iqpc.de

×