A comprehensive review of composite phase change material based thermal management system for lithium-ion batteries

This review aims to provide an insight into the composite phase change material (CPCM) based battery thermal management system (BTMS), with a focus on the improvement of battery thermal management (BTM) performance using both passive and hybrid BTMS. The mechanism of battery heat generation and temperature effect on batteries are discussed. Challenges of CPCM based BTMS are found to be mainly associated with phase change material (PCM), which has a low thermal conductivity, low form stability, bad mechanical property, and flammability issues for organic PCM. The building of heat conduction paths could effectively increase the thermal conductivity. Discussion on methods addressing this is made, including the incorporation of PCM into porous materials and dispersing thermally conductive nanomaterials within the PCM. The effects of structure/size and surface modification on the thermal conductivity enhancement are analysed. Recent progress in the PCM adsorption into porous materials and melt blending or copolymerizing with polymers have been reviewed. The methods could improve the form stability and increase mechanical property. Formulation of CPCM using flame retardant and inorganic PCMs is found to be promising to address the flammability challenge. Compared with passive cooling, the hybrid BTMS uses active cooling and thus provides a stronger cooling capacity, and the use of CPCM can enhance heat transfer further and provide better temperature uniformity. The review suggests future research focus on developing assembly methods to minimize interfacial thermal resistance, maximising the mechanical property of CPCM, and enhancing the manufacturing readiness of the CPCM based BTMS.