纯电动汽车锂离子电池热效应的建模及仿真

Modeling and simulation of thermal effects of lithium-ion battery for electric vehicles

电池热模型可用来研究电池内部的温度分布和热传递,从而进一步提高电池的安全性能。通过实验测得不同温度和荷电状态(SOC)下电动车用锂离子电池内阻的变化情况,拟合得到电池内阻和SOC的关系表达式。通过Fluent软件建立了锂离子电池的单体温度场模型并进行仿真。仿真结果表明电池壳体对电芯的散热作用明显,在建模时不能忽略;电池正负极耳对电池整体的温度影响不大,在进行电池组建模时为了加快运算,可以忽略电池极耳。

Through the cell thermal model,the temperature distribution and heat transfer inside the battery can be studied,thereby further improving the safety performance of the battery.Through the test,the data of internal resistance change with temperature and SOC were obtained,and the relation expression between the SOC and the battery internal resistance by fitting was obtained.A simulation of the lithium-ion battery temperature by Fluent was done.Simulation results show that the battery shell has significant cooling effect for batteries,and it can not be ignored while modeling; the battery electrodes have little effect for the temperature of battery,and it just impacts the temperature distribution around them,so the battery electrodes can be ignored when modeling the battery pack in order to accelerate the operation.