Simulation and analysis of heat dissipation performance of power battery based on phase change material enhanced heat transfer variable fin structure

The further development of battery thermal management phase change material (PCM) cooling technology is limited by the low thermal conductivity of a single PCM. In order to enhance the performance of thermal conductivity of phase change materials and improve the heat dissipation capacity of power battery, the fin with high thermal conductivity is used as a style of enhance heat transfer to phase change materials. The computational fluid dynamics (CFD) method is used to study the effect of parameters, such as shape, number and material of high thermal conductivity fins added in PCM as well as the air convection coefficient of shell on the heat dissipation performance of lithium ion power battery. The results show that the maximum temperature of the battery decreases the most, which is 5.57 K, when the oblique-oblique fins are added, compared with the fin without enhanced heat transfer in PCM. In the limited available space, the decrease rate of the maximum temperature of the battery does not increase with the increase of the number of oblique-oblique fins. When four oblique-oblique fins are added, the rate of decrease in the maximum temperature of the battery is the maximum, which is 0.47%. According to the thermal physical properties of each fin material and the simulation results, aluminum is the best choice for fin material. As for the convection coefficient of the air, the greater the value, the better the heat dissipation effect of the battery is.