Computational Investigation on Phase Change Material based Hybrid Battery Thermal Management System for Electric Vehicle

Abstract

The future of the automobile industry is moving towards the electrification of vehicles due to the increase in pollution and global warming. The thermal management of the battery is necessary to enhance the performance of the battery module at extreme operating conditions. Battery thermal management systems using phase change material can be used to control the temperature extremity and to achieve uniformity in temperature inside battery module. In this work, the conventional battery layout system is modified to induce the passive cooling with the use of PCM (paraffin wax) which has been placed around the periphery of each cell in the battery pack. Different thickness of PCM layer 2mm, 3mm and 4mm have been taken. This reduces the weight and cost compared to the existing PCM based BTMS. This also ensures improvise in the efficiency of the battery. The battery thermal behaviour is studied using ANSYS for various discharge rate condition (4C, 3C, 2C and 1C) with air assisted cooling system having an air flow rate of 4m/s. From the analysis, it is found that maximum temperature of a battery pack at 4C discharge rate without any BTMS is, about 60C. Elevated temperature of the battery pack covered with a PCM, for same discharge rate with same air flow rate for 2mm is 33.5C and for 3mm it is 34.4C and for 4mm it is 34.07C which falls under the optimal temperature. While adding expanded graphite to the PCM it is found that the temperature reduces to 30C for 2mm thickness PCM.