The development of phase change materials with a high latent heat of fusion and thermal conductivity is a key issue that needs to be addressed in power batteries thermal management system. In this study, an imidazolium ionic liquid ([C₁₆MIM]Br) suitable for latent heat storage was synthesized by quaternization reaction. The composite phase change material of ionic liquid/graphene/carbon nanotube aerogel was prepared by hydrothermal self-assembly and vacuum impregnation method utilizing the unique π-π interaction between the delocalized electron of the heterocyclic cation of the ionic liquid and the sp² bonded carbon materials. The prepared ionic liquid-based phase change materials had high latent heat of phase change, excellent thermal stability, and enhanced thermal conductivity. The thermal conductivity of the composite material reached 0.751 W/(m·K) at a carbon nanotubes addition of 15wt%, which was 232% higher than that of the pure ionic liquid (0.226 W/(m·K)). The enhancement was attributed to the three-dimensional network in the graphene/multi-walled carbon nanotubes aerogel which was beneficial to improve the dispersion of multi-walled carbon nanotubes in the matrix and promote the uniform penetration of the ionic liquid phase change material. As a result, the designed structure provided effective ways for phonon transmitting and improved the thermal conductivity of the composites.

开发具有高聚变潜热和高导热率的相变材料是动力电池热管理系统需要解决的关键问题。本研究通过季铵化反应合成了一种适用于潜热储存的咪唑鎓离子液体（[C _{16 MIM]Br）。}^{利用离子液体杂环阳离子的离域电子与sp 2}独特的π-π相互作用，采用水热自组装和真空浸渍法制备离子液体/石墨烯/碳纳米管气凝胶复合相变材料。键合碳材料。制备的离子液体基相变材料具有较高的相变潜热、优良的热稳定性和增强的热导率。在添加15wt%的碳纳米管时，复合材料的热导率达到0.751 W/(m·K)，比纯离子液体的热导率(0.226 W/(m·K))提高了232%。这种增强归因于石墨烯/多壁碳纳米管气凝胶中的三维网络，有利于改善多壁碳纳米管在基体中的分散，促进离子液体相变材料的均匀渗透。因此，所设计的结构为声子传输提供了有效的途径，提高了复合材料的热导率。