Thermal management analysis of simulative power batteries using phase change material and flat heat pipe

This study proposes a hybrid thermal management system (TMS) for simulative power batteries using paraffin as a phase change material (PCM) and flat heat pipes. A two-dimensional numerical model is constructed to investigate the thermal behavior of the TMS. The computed and measured results of the maximum temperature (T_Max) within the battery pack agree well for three values of heat generation rate (2, 4, and 6 W/cell). The temperature distribution and liquid fraction of PCM are also illustrated. The present results show that this system can keep T_max below the safety limit. The effects of PCM's thermal conductivity, flow rate, and inlet temperature of the water tank on T_max and temperature contour were numerically investigated. The increase in the inlet flow rate and PCM's thermal conductivity reduced the T_max in the module. As the flowrate increases from 0.5 to 0.75 l/min, T_max decreases by 7.4 °C. By adding expanded graphite (EG) to paraffin, the PCM's thermal conductivity was increased from 0.22 to 0.82 W/m K, and T_max dropped by 5.3 °C.