Numerical study of paraffin and glass fiber composites for thermal management of lithium‐ion battery packs

Abstract

Abstract Phase change materials (PCMs) have garnered significant interest in the field of passive cooling for lithium‐ion batteries in recent years due to their simple structure, low cost, and stable performance. This paper introduces a passive thermal management strategy based on nonuniform paraffin (PA) and glass fiber for battery modules. It explores the impact of glass fiber on the thermal conductivity and structural strength of PA, as well as the thermal management performance of the composite phase change battery module that combines the two materials. The findings reveal that the composite phase change module with a glass fiber mass fraction of 60%, operating at a discharge rate of 3C, maintains a temperature 0.76°C lower than that of the air‐cooling module. This reduction results in a decreased maximum temperature difference between the modules from 7.3 to 5.0°C and a decrease in the maximum temperature ratio from 16.9% to 11.6%. Moreover, compared to the PA phase change module, heat transfer to adjacent cells decreases by approximately 10% during thermal runaway, effectively suppressing thermal propagation. Additionally, the incorporation of glass fiber in this scheme enhances the compressive strength of the module by a factor of 9.81. This study presents a novel method to address the thermal management needs of batteries for heat dissipation and thermal insulation.