Influence of temperature dependent short-term storage on thermal runaway characteristics in lithium-ion batteries

In practical applications, lithium-ion batteries inevitably encounter short-term exposure to high or low temperatures due to geographical climate variations and specific usage scenarios. This study explored the impact of short-term storage at temperatures ranging from −40 to 60 °C on the thermal stability of batteries. Combustion behavior, onset time (tTR) and onset temperature (TTR) of thermal runaway (TR), flame heat flux and mass loss were measured. It demonstrates that following short-term high/low temperature storage, the amount of gas in the exhaust phase increased significantly, and the intensity of the flame jet was enhanced. The experimental results showed that the tTR and TTR initially increased and then decreased with the storage temperature decreased from 20 °C to −40 °C. High temperature storage led to earlier TR and lower TTR. Interestingly, storage at 0 °C caused a delay in the occurrence of TR. Furthermore, an analysis of the heat transfer process, spanning from the safety valve opening to the onset of TR, was performed by leveraging the characteristic time and temperature parameters observed during the TR process. The findings of this research contribute to enhancing the safety and reliability of battery applications, particularly in scenarios involving temperature variations and potential thermal risks.