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 (TMax) 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 Tmax below the safety limit. The effects of PCM's thermal conductivity, flow rate, and inlet temperature of the water tank on Tmax and temperature contour were numerically investigated. The increase in the inlet flow rate and PCM's thermal conductivity reduced the Tmax in the module. As the flowrate increases from 0.5 to 0.75 l/min, Tmax 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 Tmax dropped by 5.3 °C.