Experimental Study on Effective Thermal Management and Thermal Runaway Suppression of Lithium-Ion Battery Pack Using High Enthalpy Inorganic Hydrated Salt /Expanded Graphite Composite

Abstract

Fire and explosion incidents brought on by thermal runaway (TR) of lithium-ion batteries (LIBs) have seriously threatened people's lives and property safety. In this study, we propose an inorganic hydrated salt/expanded graphite composite (PCM-XR-39/EG CPCM) that integrates phase change and chemical thermal storage for thermal management and thermal runaway suppression of LIB pack. PCM-XR-39/EG CPCM melts at 34.5-51.6 ℃ and decomposes at 85-115 ℃ with sum thermal storage density of 1276 kJ/kg, is efficient for thermal management and thermal runaway suppression of batteries. The maximum temperature and maximum temperature difference of LIB pack are restricted within 36 ℃ and 2.5 ℃ during one charge/discharge cycle, within 50 ℃ and 5 ℃ at 10 consecutive cycles. Significantly, the temperature of needled battery is suppressed to 305 ℃ while other batteries is below 95 ℃ when TR occurs, thus TR propagation is prevented. While TR propagation occurs in battery pack with aerogel or paraffin composites (OP44/EG CPCM). The results denote that PCM-XR-39/EG CPCM has transparent advantages over aerogel and OP44/EG CPCM in preventing TR propagation. In addition, it can be concluded that to properly dredge the heat released from the runaway battery may be more effective than to simply block them.

Keywords: Inorganic hydrated salt, Phase change thermal storage, Chemical thermal storage, Thermal management, Thermal runaway propagation