A comparative study of the venting gas of lithium-ion batteries during thermal runaway triggered by various methods

Different thermal runaway triggering methods in battery safety accidents can lead to different outcomes. In this study, four testing methods, including side heating, nail penetration, overcharging, and oven heating, are used to trigger two types of batteries (prismatic cells and pouch cells) within a closed bomb. Several safety properties are investigated, including temperature, amount of venting gas and pressure, gas composition, and the mass of the thermal runaway product. Gas chromatography analysis reveals that the main components in the venting gas are CO, CO2, H2, C2H4, and CH4. Among the four tests conducted for both battery types, overcharging is identified as posing the greatest threat to battery safety. The findings from this study can contribute to assessing the risk associated with different triggers for thermal runaway.