Thermal management performance and optimization of a hybrid system integrating liquid cooling and fin-enhanced phase change material for large-capacity energy storage battery pack

Battery energy storage systems become increasingly important to address the intermittency of renewable energies, but their widespread adoption is still hindered by thermal concerns. However, a single thermal management strategy cannot ensure the overall performance of energy storage battery systems. In this study, a hybrid strategy combining topological fin structure, phase change material, and active liquid cooling is established for 280 Ah lithium-ion battery pack. A fluidic-thermal-phase change coupled model is built and verified experimentally. Meanwhile, a novel comprehensive evaluation parameter is defined to feature the overall performance of thermal management system. Based on this, comparative investigations are conducted to assess the efficiency of three cooling strategies. Despite additional weight caused by hybrid design, topological fin structure not only constructs the thermal conduction in phase change material but also dissipates the accumulated heat by connecting cold plate. Additionally, the impacts of fin fraction, thickness of phase change material, and inlet velocity are systematically explored using single-factor analysis. Furthermore, a surrogate-based model is utilized to reveal the interactions between design parameters and system performance, while accomplishing a global optimization. In contrast to original design, comprehensive evaluation parameter is reduced by 0.218, 0.273, 0.256, and 0.2 for discharge rates of 0.25, 0.5, 0.75, and 1C, respectively.