连接片阻值对电动汽车用动力电池性能的影响

The Effects of Connecting Plate Resistance on the Performance of Power Battery for Electric Vehicles

鉴于单体电池间连接片的阻值和极柱的位置影响单节电池的性能,基于Matlab/Simscape开发了单体电池模型,并利用此模型和以电阻模拟的连接片构建了单节电池模型,仿真分析了连接片阻值对单节电池性能的影响。结果表明,连接片的存在使与极柱相连的单体电池最先达到电池管理系统设定的放电截止电压,以致影响电池的性能;与极柱相连的单体电池的率先老化导致与其相邻的单体电池出现过放电的现象,影响单节电池的安全性。最后,设定各单体电池SOC间最大偏差为0.05,对不同并联电池数目的单节电池进行仿真,得出连接片与电池欧姆内阻阻值的合理比例。

In view of the effects of the resistance of connecting plates and the position of terminal post on the performance of a battery module, a model for battery cell is developed based on Matlab/Simscape, with which and connecting plates simulated as a resistance, a model for battery module is built and a simulation is conducted to analyze the effects of connecting plate resistance on the performance of battery module. The results indicate that con-necting plate make the battery cell connected directly to terminal post the first cell to reach discharge cut-off voltage set by battery management system, which influences the performance of battery. The battery cell connected to termi-nal post also ages first, leading to the over-discharge of its adjacent cell, and hence affecting the safety of battery module. Finally with the maximum SOC difference between cells set to 0. 05, battery modules with different num-bers of cells are simulated, and the reasonable ratio of connection plate resistance to battery ohmic resistance is ob-tained.