考虑老化一致性的电池模组热管理方法研究

Research on thermal management of lithium-ion battery module considering aging inconsistency

锂离子电池内部生热导致的加速老化和热安全问题一直以来都是制约电池产业的瓶颈问题。此外,单体老化路径和一致性的差异也会造成电池老化程度不一致,引发电池内阻和发热量的差异。基于上述问题,提出了一种考虑老化一致性的电池组热管理方法,搭建锂离子电池热-电耦合模型对电池进行参数辨识,并利用有限元分析的方法对Z型槽空气冷却电池组进行三维建模。分析不同外界电流应力、入口风速以及不同老化状态对电池组温度分布的影响。进行了仿真与实验验证,结果表明实验与仿真温度结果误差在2℃以内。

Accelerated aging and thermal safety problems caused by the internal heat generation of lithium-ion battery have always been a bottleneck problem restricting the battery industry.Moreover,the differences in the aging path and consistency of cells also cause inconsistent battery aging degrees,leading to the difference of internal resistance and heat generation of the battery.Based on the above problems,a thermal management method of battery pack considering aging consistency was proposed.A thermoelectric coupling model was built to identify the battery parameters,and the three-dimensional model of Z-groove air cooling battery pack was built by finite element analysis.The impacts of current stress,inlet velocity and battery ageing on the temperature distribution of battery were analyzed.The experiment and simulation were designed to validate the model.The results show that the error of experiment and simulation is below 2℃.