Thermal management for the 18650 lithium-ion battery pack by immersion cooling with fluorinated liquid

In this work, a new battery thermal management system (BTMS) utilizing a SF33-based liquid immersion cooling (LIC) scheme has been proposed. Firstly, the comparative investigation focuses on the temperature response of the LIC and forced air cooling (FAC) modules in different scenarios. The results demonstrate that LIC module effectively mitigates heat accumulation, thereby presenting notable advantages in terms of temperature control and equalization, even though the LIC module works under the stage without phase change occurrence. During 2C and 3C charging, the highest temperatures of the LIC module are observed to be 10 degrees C and 19.1 degrees C only lower than those of the FAC module, respectively. Furthermore, the highest temperature differences of the LIC module are only 12.89 % and 8.57 % of the corresponding values exhibited by the FAC module. Moreover, the associated cooling energy consumption for the LIC module is greatly reduced, amounting to only 16.47 % and 43.76 % of that required by the FAC module. Subsequently, an active control scheme for the LIC is initially proposed, and the phase change process of the LIC under various discharging rates is recorded and analyzed using a high-speed camera. This study serves as a preliminary proof of concept for the feasibility of SF33-based LIC scheme in BTMS.