圆柱型电池核心温度在线估算研究

Study on on-line estimation of core temperature in cylindrical battery

为解决圆柱型电池核心温度在线估算问题,建立了基于经典热传导理论的锂离子动力电池离散化热模型,提出了一种基于递归最小二乘算法结合热物性等效原则的模型参数辨识方法,相对于现有辨识算法收敛性更好;通过基于正交各向异性导热系数整体产热区域的电池三维热模型进行仿真计算,模拟了电池在动态工况下的内部温度分布情况,研究表明,随着外壳对流换热系数的增加,电池芯部最高温度逐步下降,但电池核心温度与表面温度之间差异性也在增加;通过在线估算算法得到的电池核心处温度与采样数据进行对比,均方根误差仅为0.3。

To solve the problem of on-line estimation of core temperature in cylindrical battery, a discrete thermal model of lithium-ion battery based on classical heat conduction theory was built, and a identification method for parameter in model based on recursive least square algorithm combined with thermo-physical properties equivalent principle was proposed, which was better than the existing identification algorithm. The internal temperature distribution of battery under dynamic operations was simulated by 3D thermal model based on the orthogonal anisotropic thermal conductivity region. The study shows that the maximum temperature of battery is gradually decreasing with the increase of the convection heat transfer coefficient for the shell, while the difference between the core temperature and the surface temperature is obvious. The average root mean square error between the sample data and core temperature calculated by on-line estimation algorithmis only 0.3.