锂电池组动态热模型在混合动力汽车中的应用

Research of dynamic thermal model for lithium battery pack used in hybrid electrical vehicle

锂离子电池热模型对于电池单体和热管理系统的设计有着重要的意义,研究串并联组合的锂离子电池组在混合动力汽车系统中的性能和寿命,提出面向控制的电池组动态热模型,该模型能根据电池组当前的环境温度、运行负荷、冷却强度和初始荷电状态实时估计电池组中各单体电池的运行温度。实验利用18650型锂离子电池单体,实现3并3串和3串3并形式的电池组循环充放电,得到单体电池温度分布曲线。仿真比较结果表明,提出的电池组热模型具有较高的估计精度,满足混合动力汽车的热管理系统的设计要求。

The thermal model was a crucial part for Battery Thermal Management （BTM） of hybrid electrical vehicle.The performance and life span of lithium battery pack under serial connection and parallel connection were focused.A control-oriented dynamic thermal model for battery pack was presented. The main feature of this model was theactual working temperature that could be estimated based on environmental temperature, operation load, coolingmethod and initial State of Charge （SOC）. The 18650-type lithium batteries were used to form the battery pack with3serial connection /3 parallel connection and 3 parallel connection /3 serial connection, respectively. The temperaturedistribution curve was obtained after charge/discharge experiments. The results show that the new model has thebetter estimation precision and can greatly meet the design requirement for BTM hybrid electrical vehicle.