Inhibiting thermal runaway propagation in lithium-ion battery pack by internal heat transfer enhancement

Abstract Safety issues caused by thermal runaway (TR) in lithium-ion batteries hinder the development of new energy technologies. Blocking the thermal runaway propagation (TRP) in battery packs is a primary approach to mitigating its hazards. This paper proposes a method for suppressing TRP by enhancing internal heat transfer in the battery. By adding heat-averaging layers to the side surfaces of the battery cores, the internal temperature distribution is optimized, allowing for effective blocking of TRP while reducing the use of thermal insulation materials. Simulation results indicate that the combination of heat-averaging layers and insulation layers can effectively suppress the TRP. The heat-averaging layers significantly improve the uniformity of temperature distribution in the thickness direction, though they may exacerbate temperature unevenness on the major surfaces. Since the thickness of the heat-averaging layers has a negligible impact on their effectiveness in blocking TRP, this method can significantly reduce the spatial requirements for TRP protection, thereby enhancing the system’s energy density.