锂离子动力电池细长形集流装置电流不均匀性分析

Analysis of Current Non-uniformity of Slender Current Collecting Device for Lithium ion Power Battery

针对动力电池组中细长形集流装置电流分布不均匀性和对角连接均流特性问题。以32650-6. 5Ah圆柱电池组成的20并1串电池组为研究对象,采用计算机模拟与试验两种方法,定量研究了1~3C工况下、电池内阻在0. 001~0. 04ohm范围内的电池组电流部均匀性。结果表明:电池内阻越小,细长形集流装置电流不均匀性越明显;电池组充放电倍率越大,不均匀性越明显;对角连接方式消除了细长形集流装置电流分布不均匀性对电池组电流不均匀性的影响;对角连接还克服因单集流装置的电压分布不均匀性造成的BMS电压采集偏差;较邻角连接方式,对角连接方式能有效地提升动力电池组性能。

This paper deals with the problem of current distribution non-uniformity and diagonal connection current sharing characteristics of slender current collecting devices in power battery packs. The 20 parallel 1 series battery pack consisting of 32650-6.5Ah cylindrical battery was used as the research object. The computer simulation and test methods were used to quantitatively study the battery with the internal resistance of the battery in the range of 0.001~0.04 ohm under 1~3C working condition. Group current section uniformity. The results show that the smaller the internal resistance of the battery, the more obvious the current non-uniformity of the elongated current collecting device;the larger the charging and discharging rate of the battery pack, the more obvious the unevenness. The diagonal connection eliminates the current distribution of the elongated current collecting device, the influence of unevenness on the battery current non-uniformity, and it also overcomes the BMS voltage acquisition deviation caused by the voltage distribution non-uniformity of the single current collecting device and can effectively improve the performance of the power battery pack.