Performance study and optimization of a hybrid liquid cooling integrated with vapor chamber and phase change material for cylindrical lithium-ion battery

To address critical thermal management challenges in high-capacity cylindrical lithium-ion batteries under high discharge rates, this study proposes a novel hybrid battery thermal management system (BTMS) that synergistically integrates liquid cooling (LC), vapor chambers (VCs), and phase change material (PCM). The innovation lies in a strategic dual-VC layout specifically designed for cylindrical batteries to significantly enhance temperature uniformity. Numerical simulations evaluate various configurations, and a multi-objective optimization framework based on artificial neural network (ANN) and genetic algorithm (GA) is developed. Results indicate that the LC-2VCs-PCM system significantly reduces battery temperature and improves uniformity. Under a 4C discharge rate with 0.02 m/s coolant flow velocity, it maintains a maximum temperature ( T max ) of 309.53 K and a maximum temperature difference (∆ T max ) of 4.56 K. These values represent improvements of 27.79 K and 25.16 K, respectively, over conventional liquid cooling. The optimized design achieves a system energy density ( ED ) of 132.12 Wh/kg, a 7.1% improvement, while reducing ∆ T max by 21% at reduced flow rate. This dual enhancement underscores the effectiveness of the proposed optimization approach in delivering superior thermal regulation and energy efficiency. Furthermore, by maintaining temperatures within a safe and uniform range, this design significantly advances battery safety by mitigating thermal runaway risks and preventing premature degradation. This study provides valuable insights for designing advanced hybrid cooling solutions.