基于复合相变材料的电池包热管理研究

Research on thermal management of battery pack based on composite phase change material

有机类相变材料导热系数普遍低,制约了其在电池热管理中的应用,通过与高导热率的材料复合能有效改善相变材料的导热性能。为明晰复合相变材料的材料属性对电池包温度分布、温升速率、温度一致性等温度特性的影响,建立了单体电池产热模型和相变材料相变模型,并通过理论计算得出复合相变材料的热物性参数。以此为基础模拟电池组在环境温度40℃、3 C恒流放电恶劣工况下的散热,分析导热填料种类及其质量分数对冷却效果的影响。结果表明:在相变热管理下,电池组最高温度能维持在50℃以内,电池表面最大温差能维持在1℃以内。

The low thermal conductivity of organic phase change materials restricts its application in battery thermal management.The thermal conductivity of phase change materials can be effectively improved by compounding with high thermal conductivity materials.In order to clarify the influence of the material properties of the composite phase change material(CMPC)on the temperature distribution,temperature rise rate,and temperature consistency of the battery pack,a single battery heat generation model and a phase change material phase change model were established,and the thermophysical parameters of the CMPC was obtained through theoretical calculations.Based on this,the heat dissipation of the battery pack was simulated under the harsh working conditions of the ambient temperature of 40℃ and 3 C constant current discharge,and the influence of the type and mass fraction of thermal conductive material on the cooling effect was analyzed.The results show that under phase change thermal management,the maximum temperature of the battery pack can be maintained within 50℃,and the maximum temperature difference on the battery surface can be maintained within 1℃.