基于灰色模型的车用三元锂电池循环寿命试验研究

Research on Cycle Life Test of Automotive Ternary Lithium Battery Based on Grey Model

车用三元锂离子动力电池是目前国内新能源汽车动力系统的主要构成部分之一,其性能会随着循环寿命的下降而发生不可逆的衰减,进而影响如续驶里程等整车性能。通过15、25和45℃环境工况下的循环寿命测试,研究了环境温度对三元锂电池循环寿命的影响。试验结果表明,当容量衰减为初始容量的88%时,45℃工况下的循环寿命为15℃工况下的三分之一。同时,基于灰色模型建立了三元锂电池循环寿命预测模型,并进行了验证,结果表明该模型精度在不同环境温度下的预测精度在1%以下,为后续的实际应用奠定了基础。

The ternary lithium-ion power battery for vehicles is currently one of the main components of the power system of new energy vehicles in China.Its performance will undergo irreversible degrada-tion with the decrease of cycle life,which will affect the overall vehicle performance such as driving range.The influence of environmental temperature on the cycle life of ternary lithium batteries was studied through cycle life tests under environmental conditions of 15℃,25℃,and45℃.Theexperi-mental results show that when the capacity decay is 88%of the initial capacity,the cycle life under 45℃conditionisone-third ofthatunder15℃condition.Atthesametime,acyclelifepredictionmod-el for ternary lithium batteries was established based on the grey model and validated.The results showed that the prediction accuracy of the model under different environmental temperatures.was be-low 1%,laying a foundation for subsequent practical applications.