Investigation on the optimization strategy of phase change material thermal management system for lithium-ion battery

Due to the lack of detailed comparison and reliability validation of paraffin (PA)-based optimization methods for lithium-ion thermal management systems, in this work, PA was selected as a phase change material (PCM). Both expanded graphite (EG) and the fin were used to optimize the thermal management performance of the PA. Charging and discharging experiments under different optimization methods were conducted, and the thermal properties of both PCMs before and after cycling were recorded to assess reliability. The experimental results indicated that both PCMs had similar thermal properties and maintained good thermal management performance after cycling. PA/EG exhibited better thermal management performance than the PA/Fin due to its excellent thermal conductivity network. Higher ambient temperatures also reduced the thermal management performance of PCM and affected the optimization of EG and Fin in the meantime. PA/EG/Fin offered the best thermal management performance, achieving a maximum 35.5 % reduction in battery temperature and controlling the temperature increase of the battery even at extremely high temperatures. This work may serve as a reference for the design of thermal management systems for lithium-ion battery, providing a basis for the application of intelligent algorithms in the optimization of thermal management of PCMs. • Different optimization methods of the paraffin-based lithium-ion battery thermal management system is investigated. • The mechanism of different optimization methods is deeply studied. • The optimization effect at different temperature is analyzed. • The reliability of phase change materials is verified.