Structural Optimization and Thermal Performance Analysis of a Bio-Inspired Leaf-Vein Liquid Cooling System for Lithium-Ion Batteries: A Case Study of Agricultural Electric Forklifts

To improve the thermal management performance of lithium-ion batteries under high discharge rates and complex operating conditions, a bidirectional parallel bionic flow-channel cooling plate is proposed, with agricultural electric forklifts taken as the representative application background. Numerical simulations were first carried out to compare the heat dissipation characteristics of a conventional leaf-vein flow channel, a unidirectional parallel bionic leaf-vein flow channel, and a bidirectional parallel bionic leaf-vein flow channel. On this basis, the effects of structural parameters on the thermal performance of the liquid cooling plate were systematically investigated using a single-factor analysis method. Furthermore, an orthogonal optimization experiment was performed for four major influencing factors. The results indicate that the unidirectional parallel bionic leaf-vein flow channel improved the coolant coverage relative to the conventional leaf-vein structure; however, owing to the one-sided coolant supply mode, a high-temperature retention zone tended to appear at the end of the channel. In contrast, the bidirectional parallel bionic design effectively alleviated this problem by supplying coolant synchronously from both sides. The main channel width, branch channel width, total channel height, and branch inclination angle were identified as the dominant factors affecting heat dissipation performance. Under the optimized structure and operating condition, the maximum temperature and temperature difference of the battery module were reduced to 29.85 °C and 4.48 °C, respectively.