锂离子单体电池散热模型及其性能研究

Study on heat dissipation model and performance of lithium-ion single battery

锂离子动力电池工作过程中的热行为对电池工作性能产生重要影响。针对锂电池的散热问题,以18650圆柱锂离子动力电池为研究对象,建立了单体电池散热模型,设计了单体电池实验测试平台,电池进行恒流放电,通过对分析模拟与实验中,电压及电池温度在不同条件下随时间变化的比较,验证了模型的准确性。基于该模型,分析了放电倍率、环境温度对电池散热的影响。结果表明:锂电池的放电倍率与环境温度和电池温度呈增函数关系,放电倍率越大,环境温度越高,电池的平均温度越高。当达到10 C时,温度将超过最佳工作温度范围,需增大风速,进行必要的散热。该电池散热模型和对单体电池散热影响因素的分析,为电池热特性的研究和热管理系统设计提供一定的参考。

The thermal behavior of lithium-ion power battery has an important impact on the performance of the battery.Aiming at the heat dissipation problem of lithium battery,taking 18650 cylindrical lithium ion power battery as the research object,the heat dissipation model of single battery was established,the experimental test platform of single battery was designed,and the battery was discharged at constant current.The accuracy of the model was verified by comparing the changes of voltage and battery temperature with time,under different conditions between the analysis of simulation and experiment.Based on the model,the effects of discharge ratio and ambient temperature on battery heat dissipation were analyzed.The results show that the discharge rate of lithium battery has an increasing function with the ambient temperature and the battery temperature.The larger the discharge rate is,the higher the ambient temperature is,and the higher the average temperature of the battery is.When it reaches 10 C,the temperature will exceed the optimal working temperature range.It is necessary to increase the wind speed and carry out necessary heat dissipation.The battery heat dissipation model and the analysis of the influencing factors of single battery heat dissipation provide a certain reference for the research of battery thermal characteristics and the design of thermal management system.