Lithium Batteries Cooling by Phase Change Material Partially Filled with Metal Foam

Abstract

Electric cars can be a turning point for climate problems. One of the main problems of electric cars is the thermal control of the batteries, since below and above a certain temperature range, the vehicle’s range decreases abruptly, creating inconveniences to the owners of these cars. The thermal control of lithium batteries for electric cars must take into account both the problems of thermal rise due to the operation of the battery itself, and the climatic conditions outside the vehicle that negatively affect the performance of the car, reducing both the autonomy and the battery life. In this study, a thermal control system based on a phase change material (PCM) partially filled with metallic foam is investigated to evaluate its possible use in the cooling of lithium batteries. A two-dimensional model is considered to numerically study thermal control with different chargedischarge cycles. The metal foam partially fills the PCM. The governing equations, written assuming the local thermal equilibrium for the metal foam, are solved by the finite volume method using the ANSYS Fluent commercial code. Different cases are simulated for different values of the external convective heat transfer coefficient. The results, carried out for metal foams and PCM, are given in terms of temperature and liquid fraction. In addition, some comparisons with pure PCM and fully foam filled PCM are provided within the thermal control system to show the advantages of the composite thermal control system with PCM inside the metal foam.