Study on the Temperature Uniformity of Lithium Batteries Based on Gradient Porous Metal Foam Saturated Liquid Cooling Plate

To improve the thermal management and temperature uniformity of lithium-ion batteries, this study proposes and evaluates a novel liquid cooling plate structure featuring gradient porous metal foam(GPFM). A fully integrated three-dimensional electrochemical-thermal coupled model was developed to accurately capture the battery's internal thermal behavior and assess the cooling plate's performance. The numerical simulations for this model were conducted using COMSOL Multiphysics. The study systematically investigated the influence of key input parameters—specifically, four distinct porosity gradient variations (defined by the gradient index n) and discharge rates (e.g., 2C, 5C, 7C)—on the primary output parameters: the battery's peak temperature and maximum temperature difference ( ). The results indicate that the designed GPFM cooling plate effectively lowers the peak temperature while markedly improving thermal uniformity. The enhancement was most evident when the gradient variation index n=2. The impact of the gradient design varied with the discharge rate. The maximum temperature reduction peaked at 13.5% under a 7C discharge rate. Conversely, the temperature difference achieved its highest percentage reduction of 58.1% at a 2C discharge rate. This study demonstrates that optimizing the porosity gradient design is an effective approach to enhancing temperature uniformity in lithium-ion batteries, particularly offering significant benefits under high-discharge-rate conditions.