Electric Vehicle Lithium-Ion Battery Thermal Management by Numerical Simulation with PCM and Fins over Shell

The study aims to develop a Battery Thermal Management System (BTMS) that incorporates phase change material (PCM) and various types and quantities of fins to reduce the battery surface temperature when discharging at varied C rates. A computational model is created to study an NMC Lithium-Ion Battery (LIB) having a form factor of 21700 and a capacity of 4900 mAh. The cylindrical battery's anisotropic thermal conductivity and specific heat capacity are used to develop a precise thermal model representing its temperature distribution. The battery is placed inside the aluminum cylindrical shell, and the fins are mounted on that shell. The gap between the shells is filled with the PCM. The investigation covers several situations, such as 1C and 2C battery discharge rates, the number of fins, and fin shapes. The fins act as a network of heat sources to disperse thermal energy evenly between the LIB and the PCM. Studying the impact of various fin shapes on the BTMS performance showed small variations in battery temperature among different fin forms. The numerical study showed that the optimal Battery Thermal Management System consisting of PCM with 10 rhombus fins could keep the battery temperature within the optimum operating range of 313.15 K when the batteries are discharged at 2C rate.