基于密胺吸附型相变材料的散热性能优化研究

Optimization of heat dissipation performance of melamine absorbed composite phase change materials

锂离子电池具有循环寿命长、安全性能好、自放电量小等优点,被广泛应用于电动汽车及储能等领域。然而,由于电池组间的散热和温度不一致,热失控事故时有发生。通过制备密胺吸附型复合相变材料并将其应用在电池模组中进行热管理,结合SolidWorks和Comsol软件,分析了不同厚度、不同导热系数下相变材料对单体电池和电池模组温度分布规律的影响;并建立了密胺吸附型相变材料的电池散热模型,采用实验与模拟相结合的方法优化其散热性能。研究结果表明,当锂电池以5 C放电时,相变材料层的厚度应大于2.5 mm,电池模组的温度可控制在43℃以内;当相变材料的导热系数提高到2.5 W/(m·K)时,电池模组最大温差减小到1.2℃。综上可知,本研究所开发的密胺吸附型复合相变材料作为被动热管理技术展现出良好的控温效果,在电动汽车及储能领域具有重要的应用价值。

Lithium ion battery has the advantages of long cycle life,good safety performance and small self discharge capacity,which is widely used in electric vehicles,energy storage and other fields.However,due to the inconsistency of heat dissipation and temperature between batteries,thermal runaway accidents often occur.Through the preparation of melamine adsorption type composite phase change material and its application in the thermal management of battery module,combined with SolidWorks and Comsol software,the influence of phase change material on the temperature distribution of single cell and battery module under different thickness and different thermal conductivity is analyzed,and the battery heat dissipation model of melamine adsorption type phase change material is established methods to optimize its heat dissipation performance.The results show that when the lithium battery is discharged at 5 C,the thickness of the phase change material layer should be greater than 2.5 mm,and the temperature of the battery module can be controlled within 43℃;when the thermal conductivity of the phase change material is increased to 2.5 W/(m·K),the maximum temperature difference of the battery module decreases to 1.2℃.In conclusion,as a passive thermal management technology,the melamine adsorption composite phase change material developed in this research shows good temperature control effect and has important application value in the field of electric vehicles and energy storage.