A manifold-based emergency thermal management system for power battery

Abstract

The thermal safety of power batteries has received much attention with the rapid development of electric vehicles. This paper proposes a manifold-based emergency thermal management system that sprays refrigerant onto the surface of overheated batteries to prevent the occurrence of thermal runaway, and the heat transfer characteristics of the manifold are investigated from spray time, spray duty cycle, and spray frequency. Studies indicate that the manifold has excellent cooling capacity for emergency thermal management needs of overheated batteries, the average temperature drop of batteries can be 65 °C in seconds. Decreasing the spray duty cycle can improve the heat transfer efficiency of the system and mitigate the cold shock to overheated batteries during spray cooling. Additionally, the cooling capacity of the system increases about 12% as the spray frequency increases from 0.33Hz to 2Hz, but the temperature uniformity of the battery module gets weakened during spray cooling. In all, the proposed thermal management system can improve the thermal safety of electric vehicles and prevent thermal runaway accidents.

Keywords

• Thermal safety
• Emergency thermal management
• Overheated batteries
• Spray cooling
• Manifold