Experimental comparison of the Li-ion battery thermal management systems using a new hybrid model of flat heat pipe coupled with phase change materials

The usage of an effective battery thermal management system (BTMS) to achieve optimal lithium-ion battery operation and prevent thermal runaway is essential. The usage of heat pipes (HPs) is considered one of the most effective techniques to cool batteries due to its high thermal conductivity. In this study, a BTMS equipped with a new model of flat HP coupled with phase change material (PCM) is experimentally investigated. The new flat HP consists of a double circular grooved evaporator and a finned condenser. The thermal performance of the new model is compared with the pure PCM model, air cooling model, and the same HP without the PCM combination. Different BTMS models are examined using various discharge rates (1C, 2C, and 3C) and air velocities, at 35 °C ambient temperature. The results indicated that the new model displays a good cooling performance, especially at high discharge rates and it can provide better protection for the batteries. Where the new model can reduce maximum operating temperature Tmax at 3C by 20.1 % and 21.1 % than the Air-Model and pure PCM-Model, respectively. Furthermore, the largest value of Tmax and maximum temperature difference using the new model did not exceed 48.1 °C and 1.8 °C, respectively. Additionally, we found the adding of the PCM to the new HP model can reduce the Tmax by 4 °C at 3C.