Effects of the battery enclosure on the thermal behaviors of lithium-ion battery module during thermal runaway propagation by external-heating

Insights into thermal behaviors of thermal runaway (TR) and propagation in a battery enclosure are significant for the safe application of lithium-ion batteries. In this study, the thermal behaviors of TR and its propagation over a lithium-ion battery module in a battery enclosure are investigated via thermal abuse experiments. The conduction heat flux between adjacent cells is measured for the first time. The results show that the onset time of the TR with the enclosure is later than that without the enclosure. However, the cells in the enclosure have a higher maximum TR temperature, and their temperature distribution is more uniform. Moreover, the duration of the TR propagation to adjacent cells in the enclosure is significantly shorter. And the occurrence of a jet fire further increases the maximum temperature of the cell in the enclosure. The measurement of the heat flux shows that the heat conduction intensity between the cells in the enclosure is greater than that without the enclosure. This work is beneficial for understanding the mechanism of TR and its propagation in practical applications and provides valuable references for the safety management of lithium-ion batteries.