三元锂电池温度-放电倍率耦合加速寿命模型研究

Study on Temperature-discharge Rate Coupling Accelerated Life Model of Ternary Lithium Battery

针对三元锂电池加速寿命测试研究中加速效果不理想的问题建立了两种模型,一种是以环境温度为单一加速因子的基于阿伦尼乌茨模型的加速寿命模型;另一种是以环境温度-放电倍率耦合条件下基于电池寿命衰退经验模型的加速寿命模型。实验结果表明:以环境温度为单一加速因子条件下加速效果有限,相比于温度和放电倍率为25℃、1 C正常条件下,50℃、1 C条件下电池循环充放电次数平均缩短290次;50℃、3 C双因子耦合条件下平均缩短510次;50℃、5 C条件下平均缩短710次。温度-放电倍率耦合情况下相比于单一环境温度情况下,能够有效缩短电池寿命测试充放电循环次数,进而缩短寿命测试时间。利用建立的双因子耦合下加速寿命模型,可以通过高水平加速因子条件去推测低水平或正常水平因子条件下电池寿命特征,从而加快得到电池寿命参数。

To study the insufficient effect of accelerated life test of ternary lithium battery,an accelerated life model based on Arrhenius model with ambient temperature as a single acceleration factor is established.The accelerated life model is based on the empirical model of battery life decline under the coupling of ambient temperature-discharge rate.The expermental results show that the acceleration effect is limited when the ambient temperature is a single factor.Compared with temperature and discharge rate at 25℃and 1 C,the average number of cycles is shortened by 290 times at 50℃and 1 C,510 times at 50℃and 3 C,and 710 times at 50℃and 5 C.The coupling of temperature and discharge rate can effectively shorten the times of charge and discharge compared with a single ambient temperature.The coupled accelerated life model is used to infer the battery life characteristics under low or normal level conditions through high-level factors.