Enhancing the performance of the hybrid battery thermal management system with different fin structures at extreme discharge conditions

This study aims to enhance the performance of the air-cooled hybrid battery thermal management system (BTMS) by using fins under extreme discharge conditions such as 7C, 9C, and 11C. In this context, five different fin structures, Type-I (no fin), Type-II (rectangular), Type-III (extended), Type-IV (blade), and Type-V (triangular), were modeled, and numerical analyses of the developed BTMSs were performed using COMSOL Multiphysics software. In the numerical analysis, three different phase change materials (PCM-1, PCM-2, and PCM-3) with three different thicknesses (tPCM) of 4, 6, and 8 mm were considered, and the airflow was supplied to the system at three different Reynolds (Re) numbers of 100, 200, and 400. In this way, the effects of the BTMS types, tPCM, PCM types, and air velocity on the battery pack temperature distribution (Delta T), PCM melting uniformity (Delta F), and maximum battery cell temperature (Tmax) in the hybrid BTMS were investigated. As a result of the analyses, the maximum Delta T was found to be 5.58 degrees C for the case involving Type-II and PCM-1 with tPCM of 4 mm at 11C. PCM-2 exhibited the best performance for all BTMS types with a tPCM of 4 mm at 9C. However, at 11C, only the case involving PCM-3 with a tPCM of 6 mm and Type-V could maintain the Tmax under 60 degrees C. Moreover, the results obtained from the numerical analysis revealed that the use of fins significantly increased the PCM melting uniformity.