Research on thermal management system of lithium-ion battery with a new type of spider web liquid cooling channel and phase change materials

Phase change materials (PCM) possess outstanding temperature control capabilities; however, it is difficult for pure PCM to satisfy the thermal management requirements under high discharge rates (4C-5C) in electric vehicles. This study designs and numerically simulates a Battery Thermal Management System (BTMS) that combines PCM with a spider web liquid cooling channel and compares it to pure PCM cooling. The results reveal that the new hybrid BTMS exhibits exceptional heat dissipation performance. Compared to pure PCM cooling, the hybrid cooling structure can maintain the Tmax of the battery module below 40 °C. Under a 5C discharge rate, the Tmax and ΔTmax of the battery module can be controlled at 39.6 °C and 4.9 °C. Based on this, the study analyzes the effects of coolant inlet Reynolds number, inlet temperature, and ambient temperature on the battery's Tmax, ΔTmax, coolant pressure drop, and PCM phase change rate under different discharge rates. This study aims to control the liquid phase rate at around 80 % and to minimize the pressure drop in the coolant as much as possible while meeting thermal management requirements. Finally, in a low temperature environment of −30 °C, with an inlet Re of 300 and an inlet temperature of 7 °C, the heating rate of the battery module with the newly designed hybrid cooling structure can reach 3.67 °C/min.