泡沫金属−PCM−液冷复合方式下动力电池散热分析

Analysis of the Heat Dissipation of Power Battery under the Composite Mode of Metal Foam-PCM-Liquid Cooling

电池是电动汽车的核心动力元件,而电池的热管理系统是动力电池发挥最佳工作性能的重要保障,在保证最佳工作性能的同时提升汽车安全性能、电池寿命及能源利用效率。基于21700NCA圆柱型三元锂离子电池,建立以泡沫铝为支撑骨架的电池组系统,在骨架和电池之间的孔隙注入相变材料(PCM)以提高结构内部温度均匀性,在电池底部添加液冷板来强化冷却效果,利用计算流体力学(CFD)仿真技术分析单体电池的耦合散热效果。结果表明,与单一冷却模式相比,使用泡沫金属与相变材料、液体冷却的耦合散热系统,可以达到更加良好的散热效果;对于相变材料,在一定密度范围内,密度越大,对电池系统的冷却效果越好,混合比主要影响相变材料的凝固融化速率。

Battery is the core power component in electric vehicles,and the battery’s thermal management system is an important guarantee for the best performance of the battery.Based on the 21700NCA cylindrical ternary lithium-ion battery,a battery pack system with foamed aluminum as the supporting framework was established in this paper.Phase change materials(PCM)were injected into the pores between the framework and the battery to improve the internal temperature uniformity of the structure.A liquid cooling plate was added to the bottom of the battery to enhance the cooling effect,and the coupled heat dissipation effect of the single battery was analyzed by computational fluid dynamics(CFD)simulation technology.Results showed that,compared with the single cooling mode,the coupling cooling system of metal foam,phase change material and liquid cooling can achieve better cooling effect.For phase change materials,within a certain density range,the higher the density,the better the cooling effect of the battery system.The mixing ratio of PCM mainly affects the solidification and melting rate of PCM.