梯次利用动力锂电池的单体电池电化学性能

随着电动汽车的快速发展,大量车用动力锂电池面临退役。对退役动力锂电池进行合理的梯次利用,可以降低动力锂电池的全寿命周期成本,提升动力锂电池的利用价值,对电动汽车行业的快速发展具有重大意义。将退役的车用动力锂电池包进行拆卸,对其单体电池外观和电化学性能进行测试,测试结果表明:单体电池的外观尺寸符合要求,开路电压压差值较小,内阻极差值达12.66 mΩ,容量衰减较为严重,在1 C下放电温升高达56℃,贮存28天后的容量保持率为89.4%。

Electrochemical performance of single cell from secondary use of power Li-ion battery

With the rapid development of electric vehicle (EV),there will be lots of retired EV power Li-ion batteries.Those Li-ion batteries should be reused to elevate the using value of batteries as well as reducing the whole life cycle cost of batteries which is very important for the rapid development of electric vehicle.The electrochemical performance of single cells from secondary use of power Li-ion battery was studied.The result shows that the looks of cells largely do not change.The open circuit voltages have a little difference over the range of 400 mV.The impedance increases to 12.66 mΩ).The capacity decreases seriously.The temperature rise can be as high as 56 ℃ when the cell discharges at 1 C.It can retain 89.4％ of the initial discharge capacity after 28 days.