Application of Refrigerant Cooling in a Battery Thermal Management System under High Temperature Conditions: A Review

Battery thermal management (BTM) is crucial for the lifespan and safety of batteries. Refrigerant cooling is a novel cooling technique that is being used gradually. As the core fluid of refrigerant cooling, refrigerants need to possess excellent properties while meeting environmental requirements. This paper elucidates the current state of refrigerants (single refrigerants and mixed refrigerants), synchronously summarizing them from the perspectives of refrigerant properties and refrigerant cooling (immersion and cold plate indirect). It outlines the advantages and disadvantages of single and mixed refrigerants as well as the research and development in the vehicle thermal management system (TMS). The choice of refrigerant directly affects cooling performance, and research on vehicle air conditioning (AC) systems can indirectly guide the BTM. R1234yf and R152a can directly replace R134a, while although R744 has a strong heating capacity, it cannot directly replace R134a. Specific mixed refrigerants reduce the global warming potential (GWP) and flammability issues, thereby improving system efficiency. Additionally, immersion cooling controls the temperature through container pressure. Coordinated control strategies are crucial for indirect cold plate cooling, offering broad prospects for optimizing the cold plate design and intelligent control. The selection of refrigerant and the optimal design of the cooling method greatly improve the thermal performance of the battery. This may promote the good development of BTM.