不同热管理方案下锂离子电池模组温度特性分析

针对锂离子动力电池在不同条件下电池模组温度变化及热失控传播特性不明晰的问题,提出了基于不同填充材料的电池热管理模拟方案。利用COMSOL Multiphysics软件,以18650电池为研究对象,建立锂离子电池模组热电耦合模型,分析不同填充材料下充放电倍率、液冷流量、液冷管排数对正常电池模组温度的影响;探究不同填充材料对电池模组热失控传播的影响;结合电池热失控试验数据验证模型准确性。结果表明,填充材料和管排数对电池正常模组温度影响较大;填充材料为石墨时最佳液冷管排数为8根;PCM材料能将对热失控传播时间控制在40~50 s/颗,相比于石墨具备明显优势。

Analysis of Temperature Characteristics of Lithium Ion Battery Modules under Different Thermal Management Schemes

To study temperature variation of the battery modules and the thermal runaway propagation characteristics of the lithium-ion power battery under different conditions,the paper provides a scheme for the simulation of battery thermal management based on different filling materials.By using COMSOL Multiphysics software,the thermoelectric coupling model was established for the lithium-ion 18650 battery module.The effects of the charge and discharge rate,the coolant flow rate and the number of tube rows of liquid cooling on the temperature of battery module during the normal operatiorn were analyzed with different filling materials.The paper investigated the influence of different filling materials on the thermal runaway propagation in the battery modules and validated the model by using the results of a battery thermal runaway test.The results show that the filling material and the number of tube rows have a great influence on the battery module temperature during the normal operation.When the filling material is graphite,the optimal number of liquid cooling tubes is 8.The PCM material can limit the thermal runaway propagation time to 40-50 s/piece,which has obvious advantages over graphite.