膨胀石墨/石蜡复合材料的制备及热管理性能

摘要

A series of expanded graphite (EG)/paraffin composites with various EG contents were prepared for Li-ion battery thermal management, in which paraffin was chosen as PCM and EG as the promoter of thermal conductivity.The thermal conductivity of the samples was measured by a thermal conductivity analyzer based on the transient hot wire method.The effect of EG content in composite on Li-ion battery thermal management was investigated.The thermal management performance of EG/PCM composites with different thermal conductivity was also discussed by software ANSYS.The results show that:EG incorporation dramatically enhances the thermal conductivity of PCM;the thermal conductivity of EG/PCM shows anisotropy, with EG content equaling to or exceeding 9%;The temperature of Li-ion battery surface decreases with an increase in EG content of composite, EG(12)/PCM(88) exhibits excellent thermal management for Li-ion battery.To adequately increase the thermal conductivity of EG/PCM in radial direction is beneficial to improve Li-ion battery thermal management.%石蜡作为相变材料(PCM),膨胀石墨(EG)为导热增强剂,制备不同EG含量的膨胀石墨/石蜡(EG/PCM)复合材料.采用瞬态热线法测量样品的导热系数;把EG/PCM应用于锂离子电池热管理,研究不同EG含量的EG/PCM热管理性能;采用ANSYS软件分析EG/PCM的导热系数对锂离子电池热管理的影响.结果表明:EG的加入大幅度提高了PCM的导热系数,EG含量≥9%时,EG/PCM的导热系数呈各向异性;锂离子电池表面温度随EG含量增加而减小,EG(12)/PCM(88)表现出优异的热管理性能;适当地提高EG/PCM的径向导热系数,有利于提高它的热管理性能.