磷酸铁锂电池恒流充电过程中的温度特性分析

Lithium iron phosphate battery temperature characteristic analysis during constant current charging

针对混合动力电动车用磷酸铁锂动力电池在大电流快速充电过程中产热易导致电池组热失控的问题,以磷酸铁锂动力电池为研究对象,分析了充电过程中电池的热特性,提出了一种基于容量增量d C/d VC的磷酸铁锂动力电池动态温度分析方法。在此基础上,对国产某方形磷酸铁锂动力电池进行了恒流充放电及其动态温度测试实验,讨论了电池容量增量与充电电压平台、产热及温度的变化关系。结果表明:电池容量增量与其温度存在动态对应关系,电池容量增量较大的电池,其产热较大和对应的温度较高,这将是电池温度控制的重点。

In the process of high current fast charging,the battery pack thermal runaway problem is easily caused by the lithium iron phosphate power battery used in hybrid electric vehicle.The thermal characteristics of the battery in the charging process were analyzed with the lithium iron phosphate power battery,and the dynamic temperature analysis method of the lithium iron phosphate power battery based on incremental capacity was proposed.On this basis,the constant current charging and discharging and its dynamic temperature test were carried out with the domestic square lithium iron phosphate power battery.The relationship between the incremental capacity with the charging voltage platform,heat production and the battery temperature was studied by the experimental data.The results show that there is the dynamic relationship between the incremental capacity and temperature,that is the incremental capacity is larger,its heat production is more and the corresponding battery temperature is higher,which will be the focus of the battery temperature control.