Effect of fin design and continuous cycling on thermal performance of PCM-HP hybrid BTMS for high ambient temperature applications

Abstract

In the present work, the thermal performance assessment of fins for a Phase Change Material-Heat Pipe (PCM-HP) based hybrid battery thermal management system (BTMS) for maintaining the average temperature of the battery surface below the safe temperature limits during continuous discharge and charge cycles is presented. A 2D computational model is used for fin design selection and to investigate the thermal performance of the PCM-HP hybrid BTMS. Two base designs and twelve fin designs with varying geometry are studied. The optimal design is chosen based on the effectiveness of the fins, the maximum battery temperature, and the PCM melt fraction. With the optimized fin design, the PCM-HP hybrid BTMS reduces the maximum battery surface temperature by 2.95 °C from 62.85 °C to 59.9 °C as compared to PCM-HP BTMS without fin. Using the selected fin the maximum battery surface temperature is maintained below 60 °C with minimum PCM melt fraction at a heat transfer coefficient of 90 W/m2K for three continuous cycles at an ambient temperature of 40 °C. Experiments are performed to verify the thermal performance of the optimized design. Further, it is observed that increasing the latent heat and thermal conductivity enhances the thermal performance of the PCM-HP hybrid BTMS.