Saturday, November 21, 2009

Lithium iron phosphate battery

The lithium iron phosphate (LiFePO4) battery (also designated "LFP") is a type of rechargeable battery, specifically a lithium ion battery, which uses LiFePO4 as a cathode material.

Contents [hide]
1 History
2 Advantages and disadvantages
3 Specifications
4 Safety
5 Usage
6 Manufacturers
7 External links
8 References
9 See also

LiFePO4 was discovered by John Goodenough's research group at the University of Texas in 1996[1],[2] as a cathode material for rechargeable lithium batteries. Because of its low cost, non-toxicity, the high abundance of iron, its excellent thermal stability, safety characteristics, good electrochemical per­formance, and high specific capacity (170 mA·h/g) it gained some market acceptance.[3][4]

The key barrier to commercialization was its intrinsically low electrical conductivity. This problem, however, was then overcome partly by reducing the particle size and effectively coating the LiFePO4 particles with conductive materials such as carbon, and partly by employing the doping[3] approaches developed by Yet-Ming Chiang and his coworkers at MIT using cations of materials such as aluminum, niobium, and zirconium. It was later shown that most of the conductivity improvement was due to the presence of nanoscopic carbon originating from organic precursors.[5] Products using the carbonized and doped nanophosphate materials developed by Chiang are now in high volume mass production by A123Systems and other companies[citation needed], and are used in industrial products by major corporations including Black and Decker's DeWalt brand, General Motors' Chevrolet Volt, Daimler, Cessna and BAE Systems.

Most lithium-ion batteries (Li-ion) used in consumer electronics products are lithium cobalt oxide batteries (LiCoO2). Other varieties of lithium-ion batteries include lithium-manganese oxide (LiMn2O4) and lithium-nickel oxide (LiNiO2). The batteries are named after the material used for their cathodes; the anodes are generally made of carbon and a wide variety of electrolytes are used.

[edit] Advantages and disadvantages
The LiFePO4 battery uses a lithium-ion-derived chemistry and shares many of its advantages and disadvantages with other lithium ion battery chemistries. The key advantages for LiFePO4 when compared with LiCoO2 are improved safety through higher resistance to thermal runaway, longer cycle and calendar life, higher current or peak-power rating, and use of iron and phosphate which have lower environmental impact than cobalt. Cost may be a major difference as well, but, that cannot be verified until the cells are more widely used in the marketplace[citation needed].

LFP batteries have some drawbacks:

The specific energy (energy/volume) of a new LFP battery is somewhat lower than that of a new LiCoO2 battery. Battery manufacturers across the world are currently working to find ways to maximize the energy storage performance and reduce size & weight.[6]
Brand new LFP's have been found to fail prematurely if they are "deep cycled" (discharged below 33% level) too early. A break-in period of 20 charging cycles is currently recommended by some distributors.[citation needed]
Rapid charging will shorten lithium-ion battery (including LFP) life-span when compared to traditional trickle charging.[citation needed]
Many brands of LFP's have a low discharge rate compared with Lead-Acid or LiCoO2. Since discharge rate is a percentage of battery capacity this can be overcome by using a larger battery (more Amp-Hours).
While LiFePO4 cells have lower voltage and energy density than normal, LiCoO2 Li-ion cells, this disadvantage is offset over time by the slower rate of capacity loss (aka greater calendar-life) of LiFePO4 when compared with other lithium-ion battery chemistries (such as LiCoO2 "cobalt" or LiMn2O4 "manganese spinel" based Lithium-ion polymer batteries or Lithium-ion batteries).[7][8] For example:

After one year of use, a LiFePO4 cell typically has approximately the same energy density as a normal, LiCoO2 Li-ion cell.
Beyond one year of use, a LiFePO4 cell is likely to have higher energy density than a normal, LiCoO2 Li-ion cell due to the differences in their respective calendar-lives.

Cell voltage = Min. discharge voltage = 2.8V. Working voltage = 3.0V to 3.3V. Max. charge voltage = 3.6V.
Volumetric Energy density = 220 Wh/L
Gravimetric Energy Density = 90+ Wh/kg [1]
100% DOD cycle life = 2,000-7,000 (Number of cycles to 80% of original capacity)

Cathode Composition (weight)
90% C-LiFePO4, grade Phos-Dev-12
5% Carbon EBN-10-10 (Superior Graphite)
Cell Configuration
Carbon-Coated Aluminum current collector 15
1.54 cm2 cathode
Electrolyte: EC-DMC 1-1 [[LiClO4]] 1M
Anode: Metallic lithium
Experimental conditions:
Room temperature
Voltage limits: 2.5 – 4.2V
Charge: C/4 up to 4.2V, then potentiostatic at 4.2V until I

LiFePO4 is an intrinsically safer cathode material than LiCoO2 and manganese spinel. The Fe-P-O bond is stronger than the Co-O bond, so that when abused, (short-circuited, overheated, etc.) the oxygen atoms are much harder to remove. This stabilization of the redox energies also helps fast ion migration. Only under extreme heating (generally over 800 °C) does breakdown occur and this bond stability greatly reduces the risk of thermal runaway when compared with LiCoO2.

As lithium migrates out of the cathode in a LiCoO2 cell, the CoO2 undergoes non-linear expansion that affects the structural integrity of the cell. The fully lithiated and unlithiated states of LiFePO4 are structurally similar which means that LiFePO4 cells are more structurally stable than LiCoO2 cells.

No lithium remains in the cathode of a fully charged LiFePO4 cell — in a LiCoO2 cell, approximately 50% remains in the cathode. LiFePO4 is highly resilient during oxygen loss, which typically results in an exothermic reaction in other lithium cells.

LFP batteries were featured on the November 5, 2008 episode of Prototype This!. They were used as the power source for a hexapod (walking) vehicle. Lithium Technology Corp. announced in May 2007, that they had developed a new Lithium Iron Phosphate battery with cells large enough for use in hybrid cars, claiming they are "the largest cells of their kind in the world."[9]. While they may be large enough for such uses, there remain limitations to the use of this particular Lithium battery technology which may make their use contraindicated. See Advantage and Disadvantages above for details.

Thundersky LiFePO4 batteries have become the most popular lithium-ion batteries used in hobbyist electric vehicle (EV) conversions since they are relatively inexpensive and easily obtainable from retail sources.

This battery is used in the electric cars made by Aptera [10] and QUICC

This type of battery technology is used on the One Laptop per Child (OLPC) project

Electric bicycle conversion kits distributed by include lithium iron phosphate battery technology[13].

Killacycle, the worlds fastest electric motorcycle, uses lithium iron phosphate batteries.

Segway Personal Transporters advanced from a 10 mile range to a 24 mile range with Valence Lithium Phosphate technology.[citation needed]

OLPC batteries are manufactured by BYD Company of Shenzhen, China, the world's largest producer of Li-ion batteries. BYD, also a car manufacturer, plans to use its Lithium Iron Phosphate batteries to power its PHEV, the F3DM and F6DM (Dual Mode), which will be the first commercial dual-mode electric car in the world. It plans to mass produce the cars in 2009.[14]

LFP batteries are gaining popularity now in the world of hobby-grade R/C, due to the benefits over the ever-popular LiPo batteries. They can be recharged much faster and for more cycles, are not prone to catching fire or exploding while recharging, and are more robust than the LiPo type.

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Chinese EV is on the move! Check this out..BYD F6DM

BYD F6DM (BYD: Build Your Dreams)Plug-in Hybrids.

Manufacturer BYD Auto
Production 2009
Class Electric MPV
Body style(s) 5-door hatchback
Engine(s) one or two permanent magnet synchronous motors
Wheelbase 2,830 mm (111.4 in)
Length 4,554 mm (179.3 in)
Width 1,822 mm (71.7 in)
Height 1,630 mm (64.2 in)
Curb weight 2,020 kg (4,453 lb)
Fuel capacity 48 or 72 kW·h (Li-ion Fe battery)
Electric range 400 km (250 mi)

Electric power consumption: less than 18kWh/62 miles (100 km)
0-60 mph (0-96 km/h) acceleration in < 8 seconds
Top speed 100 mph (160 km/h)
Normal charge: 220V/10A household electric power socket
Quick charge: 50% capacity in 10 minutes
Range: 249 miles (400 km), the longest range of its kind in the world

BYD’s "Fe" lithium iron phosphate battery, which powers the e6, represents one of the company’s core technologies. All chemical substances used in the battery can be recycled. There are four different power combinations planned for the e6: 101 hp (75Kw), 101+54 hp (75+40Kw), 215 hp (160Kw) and 215+54 hp (160+40 kW).[2] The two-motor options use front and rear engines, making the car all-wheel drive.

A range of 400 km and consumption of 18kWh per 100 km implies a 72 kWh battery pack, which will be the largest in any production electric car. BYD mentioned a smaller 48 kWh battery pack for the e6[3] at its debut at the 2009 North American International Auto Show.

[edit] Interior
The e6 features the latest body/frame-integral construction, with the battery pack well-protected in a specially designed safety cell that's fully integrated into the vehicle.

The 5-passenger e6 will be marketed as a family-oriented crossover vehicle. The high-tech e6 boasts the exterior dimensions of a typical American family vehicle, with ample interior space that provides substantial legroom and headroom for passengers, plus a generous luggage compartment.

[edit] Price
The e6 will be available in the United States in 2010 at a price just over $40,000. [4]

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ディーゼルハイブリッドとエアロダイナミクスデザインによって、欧州複合モード燃費で72.46km/Lを叩き出すVWのスーパー低燃費ハイブリッドカー。 L1のボディはCFRP(炭素繊維強化プラスチック)のモノコック構造で、車重はわずか380kg。全長は3813mmとフォックスとほぼ同サイズだが、徹底的な空力追及により幅は日本の軽自動車より30cm近くスリムな1200mm、全高も1143mmとスポーツカー並みに抑えられ、Cd値は0.195をマークする。乗車定員は前後1座ずつの2名仕様だ。




2002年に発表され、当時の取締役会会長だったDrピエヒがステアリングを握った1リッターで100km走るコンセプトカーの「VW L1」は市販予定はなかったが、今回のL1コンセプトは最終的に量産を視野に入れているというのも凄い。

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三菱 i-MiEV、英国に上陸






レスポンス 森脇稔


スマート EV、量産第1号車がラインオフ







スマートブランドの販売&マーケティング担当のMarc Langenbrinck氏は、「フォーツーedは、理想的なシティコミューターとなり得る」と自信を見せている。

レスポンス 森脇稔

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Thursday, November 19, 2009

EV 555.6Km/charge!

 電気自動車による途中無充電での560kmに及ぶ走行は、10月27日に米国Tesla Motorsの打ち立てた途中無充電航続距離501kmを抜く世界新記録となるため、すでにギネスに申請していると言う。



出発 2009年11月17日(火) 午前3時 東京日本橋
到着 2009年11月17日(火) 午後3時~4時 大阪日本橋
走行車両:ミラEV (日本EVクラブ製作)
モーター: DCブラシレス同期型
最高出力:35 kW    
電池:三洋電機 リチウムイオン
総電圧:240.5 V      
総電力量:74 kWh

協賛 東洋ゴム工業株式会社 株式会社トーヨータイヤジャパン
協力 三洋電機株式会社
主催・企画・運営 日本EVクラブ


2009-11-19 07:10:53
東京~大阪間560km=EV無充電走行 日本EVクラブ


2009-11-17 19:29:59

走行時間は約13時間半。 ※@41.2km/h相当
日本EVクラブは11月16日、自作の電気自動車による走行イベント「東京~大阪途中無充電ミラEVの旅 そんなに走ってどうするの」の出発式を行った。


無充電の旅に使用するクルマ(ミラEV)は、普通の軽自動車(ダイハツ・ミラ バン)

ベース車両 ダイハツ・ミラ・バン
変速機 5速MT
駆動方式 前2輪駆動
全長×全幅×全高 3395×1475×1530mm
ホイールベース 2490mm
トレッド 前/後 1320/1310mm
車両重量 860kg  最大積載量 200kg
乗車定員 2名
種類 DCブラシレス同期型
定格出力 14kW  最高出力 35kW
電池 :メーカー 三洋電機
種類 リチウムイオン  型式 UR18650F
本数 8320本
※ 電池はノートパソコン等に用いる汎用のもの
総電圧V 240.5V  総電力量 74kWh
タイヤ :メーカー東洋ゴム
ブランド TOYO TIRES ECO WALKER(エコ・ウォーカー)
サイズ 165/50R15


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