Thermal–hydraulic design and multi-objective optimisation of a cicada-wing-vein-inspired liquid cooling plate for lithium-ion battery thermal management

To improve the thermal safety and temperature uniformity of lithium-ion batteries under high-rate discharge, a cicada-wing-vein-inspired liquid cooling plate with hierarchical branching and lateral interconnections was developed. Three channel configurations, including rectangular, inclined-branched, and multilevel biomimetic branched channels, were progressively constructed to clarify the influence of branch evolution on coolant distribution, heat transfer, temperature uniformity, and hydraulic resistance. The results demonstrate that the multilevel lateral interconnections of the cicada-wing-vein-inspired structure promote transverse coolant redistribution and provide a favourable thermal–hydraulic balance. Subsequently, the branch number, branch angle, channel width, and channel height were optimised using orthogonal design, surrogate modelling, and the Non-dominated Sorting Genetic Algorithm II (NSGA-II). Compared with the initial biomimetic plate, the parameter-optimised plate reduced the maximum temperature and average temperature by 1.79% and 1.39%, respectively, improved temperature uniformity by 13.28%, and reduced the pressure drop by 29.85%. Topology optimisation was then employed as a further structural refinement using the optimised biomimetic channel as the initial configuration. At a coolant mass-flow rate of 3.5 g/s, the resulting biomimetic topology-optimised plate reduced the maximum temperature, average temperature, and temperature standard deviation by 0.36°C, 0.34°C, and 0.09°C, respectively, while decreasing the pressure drop by 49.39 Pa relative to the parameter-optimised plate. Unlike conventional tree-like biomimetic channels, whose daughter branches are not directly connected after bifurcation, the proposed design provides multiple cross-branch flow paths for lateral coolant redistribution. It therefore offers an effective approach for balancing cooling performance, temperature uniformity, and hydraulic resistance in battery thermal management systems.