Thermal management performance and optimization of a novel system combining heat pipe and composite fin for prismatic lithium-ion batteries

The heat dissipation is a main factor affecting the performance of lithium -ion batteries, and a battery thermal management system (BTMS) with excellent comprehensive performance is vital to the safety of the battery module. This study proposed a novel BTMS that utilized the heat pipe coupling composite fin (HPCF) which consisted of aluminum fin, phase change material and liquid cooling tube. The thermal performance of four passive systems including natural cooling, single heat pipe cooling, heat pipe coupling traditional fin cooling and HPCF were compared by model, among which the HPCF displayed superior thermal performance to other systems. The temperature of HPCF were still within the desired range without intervention of active technology even at the ambient temperature of 30 C-degrees and discharge rate of 2C. A novel comprehensive criterion, thermogravimetric coefficient integrating maximum temperature, temperature difference, energy density was developed to assist in optimizing the structure of passive BTMS. By single parameter and response surface analysis, the comprehensive performance of the HPCF was improved by 22.19 %. Finally, an optional liquid cooling strategy of the controllable ambient temperature range at a certain flow velocity was proposed for high ambient temperature and discharge rate, which can not only meet the battery heat dissipation requirements in extreme environments, but minimize the energy consumption and mechanical losses caused by frequent regulation of the flow velocity.