Pouch Lithium Battery with a Passive Thermal Management System Using Form-Stable and Flexible Composite Phase Change Materials

Paraffin (PA) as a phase change material (PCM) has become one of the research hotspots for battery thermal management systems owing to its high latent heat, low cost, simple structure, and other merits. However, it has been inevitably restricted by its low thermal conductivity, heat-storage saturation, and poor adaptability, especially for a battery module. In this study, a novel form-stable and flexible composite PCM (CPCM) with high latent heat has been successfully prepared; styrene–butadiene–styrene (SBS) and thermoplastic ester elastomer (TPEE) as the supporting skeleton material and collaborative packaging material can effectively improve the flexibility and deformation of CPCM. Besides, expanded graphite (EG) is utilized to enhance the heat-dissipating capacity and balance the temperature difference. The results indicate that CPCM has good physical and chemical compatibility, and it can also achieve stable deformation performance such as bending and stretching without fracture, which are beneficial to reduce thermal contact resistance and improve external force resist as a buffer layer. Besides, the thermal management system with TPEE-SBS/EG/PA for the battery module can exhibit an excellent temperature-controlling performance. Thus, it should be concluded that the form-stable and flexible CPCM can be used for a long-term thermal management system and has potential application prospects in heat storage and other fields.