基于相变材料的方形动力电池散热模拟研究

Simulation of heat dissipation with phase change material for prismatic power battery

首先对电池的产热方式进行了分析,然后根据相变问题求解焓法模型以及相关热传导理论,建立了基于相变材料的方形单体电池散热三维热模型。在此模型基础上结合方形电池表面的外形结构,分析了不同相变材料结合方式,不同相变材料用量以及不同表面换热系数对电池工作温度的影响。研究表明:在电池四周包裹相变材料比只在两侧结合的方式具有更好的降温能力,但是两侧结合具有更小的温差;相变材料厚度3 mm或对流换热系数达到21 W/(m^2·K)时,可以使电池的工作温度始终低于50℃,但是继续增大数值取得的效果不明显。

The heat production mode of battery during discharge was analyzed, and then a three-dimension thermal model for the prismatic battery with phase change material（PCM） was set up using the enthalpy model in conjunction with heat transfer theory. Base on the model, the influence of different combining ways, dosage of PCM and surface convective heat transfer coefficient on the heat dissipation of the battery were analyzed. The investigated results show that PCM wrapped around the battery has a better performance in temperature reduction, but with a higher temperature difference than only two sides; the operating temperature of the battery will be always lower than 50 ℃ when the thickness of phase change material board is 3mm or the heat transfer coefficient reaches to 21 W/（m^2·K）, but the effect of these two factors is not obvious when they reach a certain value.