Enhancing Thermal Stability in Prismatic Lithium-ion Battery Pack in Electric Vehicle through Optimization for an Indirect Liquid-cooling System

Abstract In an electric vehicle battery pack, thermal stability degradation due to temperature differences is the cause of performance degradation and thermal runaway. Therefore, an effective battery cooling system design is essential to increase the thermal stability of the battery pack. In this study, surrogate model-based optimization is used to minimize the maximum temperature difference of a prismatic lithium-ion battery pack with an indirect cooling system. In the optimization process, the cooling system mass is constrained along with the maximum temperature of the battery and pumping power. Design of experiments is utilized to identify significant design variables, analyse influence of design variables on responses, and generate a surrogate model. The optimization results showed a 14.48% reduction in the maximum temperature difference, from 8.21 to 7.02 K, relative to the initial cooling system design.