考虑电池产热的多孔介质复合相变材料的传热性能

Heat transfer in porous medium composite phase change materials with battery heat generation

高能量密度电池作为新能源汽车的主要能源,其热安全问题受到学者们的广泛关注,而电池热管理系统能有效防止电池热失控。该文基于相变热管理技术原理,构建多孔介质复合相变材料(CPCM)的传热与电池产热的耦合模型,利用数值算法与粒子图像测速技术(PIV)相结合的研究方法,开展了多孔介质复合相变材料中锂离子电池的产热规律及复合相变材料的传热性能研究。结果表明:多孔介质可以有效地加速相变材料的熔化进程;复合相变材料可以减缓电池温度的上升速率;电流强度对热管理系统的熔化进程、储热量以及储热效率有明显影响。复合相变材料可以提高电池内部散热效率从而减缓电池温度的上升。当考虑双体电池模型时,应尽可能在电池间保持一定的空间,从而有利于电池热管理系统的散热。

New energy vehicles are mainly powered by high energy density batteries that can experience thermal safety issues that have received extensive attention from researchers. The battery thermal management system is designed to prevent thermal runaway in the batteries. This paper presents a coupled heat transfer and battery heat generation study using porous medium composite phase change materials(CPCM) for battery thermal management. The study uses numerical models and experiments with particle image velocimetry(PIV) to research the heat generation in lithium-ion batteries in the porous composite phase change unit and the heat transfer in the composite phase change materials. The results show that the porous media accelerate melting of the phase change materials(PCM), composite phase change materials can slow the battery temperature increase and the current intensity can significantly impact the melting process, energy storage and energy storage efficiency of the thermal management system. Thus, the composite phase change material improves the heat dissipation in the battery which slows the temperature increase. Dual-battery models should have a space between the batteries to improve the heat dissipation for the thermal management system.