锂离子电池充放电倍率对容量衰减影响研究

Influence of charge and discharge rate on capacity fade of lithium ion battery

锂离子电池比能量高、循环寿命较长且使用性能稳定,目前广泛应用于电动汽车。寿命是电池重要性能指标之一,而电池容量衰减快慢决定着寿命的长短,且充放电倍率与其密切相关。通过不同充放电倍率下的电池容量测试实验和加速老化实验,得到不同循环次数下的电池外特性数据,进而研究充放电倍率对电池循环老化容量的影响。对比分析后推断电池在老化初期的容量衰减主要原因是可循环锂离子的减少和活性物质的损失,且充电倍率对电池容量衰减的影响最为明显。

The lithium ion battery is widely used in electric vehicles because of its high specific energy,long cycle life and stable performance.Lifetime is one of the important performance indicators of the battery.The battery capacity decay determines the length of life,and the charge and discharge rate is closely related to capacity.Through the battery capacity experiment and accelerate aging experiment under different charge and discharge rates,the effect of charge and discharge rate on the cycle aging capacity of the battery was studied,and the battery external characteristic data of different cycle times were obtained.After comparing and analyzing,it was concluded that the capacity fading of the battery in the early stage of aging was mainly due to the reduction of recyclable lithium ions and the loss of active materials,the effect of charging rate on battery capacity attenuation is most pronounced.