Investigation on thermal management of cylindrical lithium-ion batteries based on interwound cooling belt structure

Battery thermal management is a major challenge for battery electric vehicles, with thermal runaway incidents sparking public safety concerns. Aiming to tackle the issues of excessive module temperature and inadequate thermal balance of vehicle power batteries under high discharge rates, a novel interwound cooling belt structure for cylindrical lithium-ion batteries based on the temperature distribution characteristics of battery modules is proposed. A comparative analysis of thermal–hydraulic performance across four cooling structures demonstrates that the proposed design exhibits superior efficacy in battery thermal management applications. The effect of cooling belt geometry on thermal management performance under fixed mass flow rates is systematically investigated. Thermal-hydraulic analysis demonstrates that a bifurcated cooling belt design with 24 mm (main) and 16 mm (branch) heights maximizes heat dissipation efficiency. Orthogonal test design is adopted to evaluate the influence of cooling channel geometry (heights), inlet coolant temperature, and mass flow rate on the thermal performance of the interwound cooling belt structure. Optimal configurations are determined through a balanced multi-parameter optimization approach. The optimized configuration exhibits superior thermal–hydraulic performance relative to the baseline, with maximum temperature (T_max) being 6.31 K lower, maximum temperature difference (ΔT_max) reduced by 0.18 K, and the pressure drop (ΔP) cut by 39.02 %.