Experimental investigation of heat pipes and liquid cooling based hybrid Battery Thermal Management System

The thermal management system (TMS) for lithium-ion (Li-ion) batteries in electric vehicles (EVs) is an essential requirement to ensure their smooth operation due to the high temperature generated by the batteries during high C rate charging or discharging. In the current study, this paper presents an analysis of the performance of a heat pipe-assisted hybrid cooling battery thermal management system (BTMS) for electric vehicle (EV). Combining a cooling channel and round heat pipes (RHP) at system level, this study examines the vertical position of the RHP under various heat load conditions and liquid temperatures. Moreover, the study also goes through thermal resistance network of the entire system and determines the part with high temperature gap. Experimental results demonstrated that the current design with heat pipes in vertical position is capable of transferring heat released at 1.126 10 6 / 3 (10W) from heater cartridges. This was enough to keep the battery surface temperature below 59C and the difference in temperature between them under 2C. Furthermore, the heater cartridge surface temperature showed 39C when 5W heat power was released. The two test cases were conducted at 0.33 L/min and 20C water temperatures which is the average ambient temperature. Finally, it should be noted that the decrease in the temperature of the water from the cooling tower is proportional to the decrease in the temperature of both ends of the heat pipe.