large battery cell characteristics of Electric vehicle
GS Yuasa in the “AABC 2008″ (5 14 ~ 16, the United States Tampa), Laptop batteries the use of electric vehicles, lithium-ion rechargeable battery delivered a speech entitled “R & D Status of Lithium-ion Batteries for Various Applications in GS Yuasa” in the speech. The company has developed electric hybrid with high output power of type “EH6″ and electric vehicles with high-capacity type “LEV50″. Taking into account the safety, heat dissipation and manufacturing cost, two kinds of cell are used in a rectangular container.
EH6 the current capacity of 6Ah, voltage of 3.7V. Overall size 112mm × 21mm × 82.6mm, weight 331g. The energy density per unit weight 67.1Wh/kg, the energy density per unit volume 114.3Wh / L. Cathode material used for cobalt (Co), nickel (Ni), manganese (Mn) ternary material. Of its excellent low temperature properties, even in -30 ℃ low temperature, the capacity maintenance rate can reach 90%. Output characteristics, the in the SOC (state of charge) 50% of the state output of 10 seconds, the output power of 1200W (3600W/kg), the SOC is 20 ~ 70% of the state output of 1 second, it can ensure that more than 1000W .
In addition, electric vehicles using lithium-ion rechargeable batteries, GS Yuasa, Mitsubishi Corporation will be a joint venture with Mitsubishi Motors - Lithium Energy Japan invest 4 billion yen to establish production lines, is expected to begin in 2009 with an annual output of 200,000 cell size, production of Mitsubishi’s electric vehicle “i MiEV” for use LEV50 lithium-ion rechargeable battery.
LEV50 the current capacity of 50Ah, voltage of 3.7V. Overall dimensions of 113.5mm × 43.8mm × 171mm, weight 1.7kg. The energy density per unit weight 109Wh/kg, unit volume energy density of 218Wh / L. To 300A high-current discharge (6C discharge), it can ensure that 88% of capacity. Properties at low temperature area, -25 ℃ can maintain 86% capacity.
Output characteristics, using a 300A discharge, the output power 500W/kg. Input characteristics in order to 125A charging, the input power reaches 300W/kg. Temperature environment at 25 ℃ under a full charge and discharge cycle life Dell GD761 batteryrytests showed that even after 1000 cycles to maintain the capacity to maintain the rate of 85%.
The company also announced the independent development of the carbon-load-type lithium iron phosphate (LiFePO4) battery cells used in large-scale positive results. Using the external dimensions 115mm × 47mm × 170mm square “LIM40″ industrial batteries, cell implementation of the pilot showed that, even with a 400A high-current discharge capacity almost does not decrease. Without the use of the carbon load of the company’s original product, the 400A discharge to 40A discharge capacity of more than half. In addition, the trial of this product may be sufficient to use low temperature -20 ℃.