Design of an Air-Liquid Coupled Thermal Management System for Battery Packs in Energy Storage Cabinets

Efficient thermal management is critical for ensuring the performance and safety of large-capacity battery packs. Traditional air or liquid cooling methods often fail to provide sufficient cooling and to maintain uniform temperature distribution. To address these limitations, a novel hybrid air-liquid cooling system was developed in this study. A 3D model of the proposed cooling structure was constructed. Heat transfer and fluid flow resistance were analyzed using computational fluid dynamics (CFD) simulations based on the developed model. The model was validated through experimental measurements. These included discharge temperature rise measurements on individual battery cells and flow resistance tests on the liquid cooling plate. The thermal performance of the air-liquid hybrid cooling system was evaluated at various discharge rates and compared with only air or liquid cooling methods. Results indicated that the hybrid cooling system significantly enhanced heat dissipation. At a 0.5C discharge rate, the maximum temperature difference was decreased by more than 4°C compared to air cooling and by more than 2°C compared to liquid cooling. Peak temperatures were decreased by more than 9°C compared to air cooling and by 2°C compared to liquid cooling. The effects of key parameters, such as coolant flow rate, fan speed, channel width, and channel depth, on cooling performance were investigated. A turbulence-inducing structure was proposed to improve cooling efficiency. Under the 0.5C discharge condition, the optimized cooling system maintained peak temperatures of the batteries below 35°C and temperature differences within 5°C. This study presents an effective hybrid air-liquid cooling solution for large-capacity battery packs and provides valuable insights for developing advanced thermal management systems.