Experimental study of thermal runaway propagation suppression of lithium-ion battery module in electric vehicle power packs

In this study, the thermal runaway (TR) suppression test platform of battery modules was built based on the real power battery pack to reduce the thermal runaway propagation (TRP) of electric vehicle power battery packs. The inhibition effect of different fire extinguishing devices on TRP of ternary lithium-ion battery modules was experimentally investigated. Big scale tests yielded combustion behaviors, TRP intervals, peak temperatures, cooling efficacy of extinguishants, heat transfer, and fire traces of the battery modules. Notably, perfluorohexanone application prolonged the TRP by 427 s relative to the blank control experiment, reducing the cell casing temperature to 267 ℃, although it did not fully arrest TRP between cells. However, water mist application effectively halted inter-cell TRP, ensuring post-spray temperatures at thermocouple sites remained below 100 ℃ and reduced heat transfer best. These findings deliver crucial experimental insights that bolster the development of fire extinguishing strategies for the safety management of electric vehicle power battery assemblies.