基于热平衡法的方壳电池电芯温度预测模型

Temperature Prediction Model for Square-Case Battery Cells Based on Thermal Equilibrium Method

据不完全统计,电动汽车大多在充电过程中发生自燃,如何在热失控前通过温度进行预警显得尤为重要。针对方形锂离子电池,构建了适用于嵌入式应用的电芯温度预测模型。通过试验精准测量电池各项热物性参数,对电池表面和电池卷芯分别进行热平衡分析,建立不同的能量守恒方程,对电池进行网格划分,进一步构建电池三维温度预测模型。仿真结果表明,热平衡模型不仅能够预测出电池每一部分的温度,而且预测的电芯温度误差不超过0.35℃,对快充条件下的电池温度预测有重要意义。

According to incomplete statistics,spontaneous combustion of electric vehicles most likely occurred during the charging process,and therefore early warning of temperature rise before thermal runaway is particularly important.A cell temperature prediction model for square lithium-ion batteries was constructed for embedded applications.Based on the experimental measurement of thermal physical parameters for the battery,the thermal equilibrium analysis of the surface and interior of the battery was carried out separately.Energy conservation equations were established and the meshing of the battery module was conducted to further construct a three-dimensional temperature prediction model.The simulation results show that the thermal equilibrium model can predict the temperature of each part of the battery,and the error of the predicted cell temperature does not exceed 0.35℃,which is important for the battery temperature prediction under fast charging conditions.