Effects of vertical position of exhaust valve on jet fire situations caused by thermal runaway in electric vehicle battery packs

The jet fire phenomenon caused by thermal runaway (TR) in electric vehicle (EV) battery packs is a key factor affecting people’s trust in EV safety. This phenomenon has already affected the development of EVs. The gas vent of EV battery packs, which serves as the main fuel for jet fire, has a considerable influence on it. The gas vent process directly affects the overall safety performance of the vehicle. Therefore, it makes sense to study the vertical arrangement of the exhaust valve position. In this study, the effect of Vertical position of EV on TR induced jet fire in an electric vehicle battery pack is investigated using numerical analysis. Results indicate that placing the exhaust valve in a high position reduces the interaction between the gas vent and the ground, resulting in a decrease in the spread distance and speed of jet fire; high-placed exhaust valves result in a decrease of 2 m in maximum flame length compared with low-placed exhaust; when reaching its peak for the first time, the high-positioned exhaust valve experiences delays of 1.23s and 1.62 s compared with when it is centrally or low positioned, respectively.