Study on the performance of Li-ion power batteries

The preparation methods of Li-ion power batteries with nominal capacity 10Ah were studied.And their charge/discharge,over charging and consistency performance were evaluated.The results showed that the energy density of 10Ah battery was higher than 165Wh/kg.When charging and discharging at 0.5C,the capacity retention of battery was 90% of the initial after 500 cycles.The capacity retention was 75% and 70% at-10℃ and-20℃,respectively.The overcharging voltage of 10Ah battery only reached 5.0V,thus its performance needed to be further improved.When discharging at 0.1C,0.2C,0.5C and 0.8C,all the voltage plateaus of 10 Ah batteries exceeded 3.6V and the voltage difference was less than 0.08V.These batteries exhibited good consistency and achieved the performance index of power lithium ion secondary battery.