Abstract: In order to study the thermal runaway fire process of the vehicle power battery pack storage device, which is along with early-warning and prevention ability. The significance of the early warning signal sequence of thermal runaway fire was analyzed through real tests and simulation of the vehicle power battery pack, and the temperature distribution near the spread and spread of the battery pack fire was studied. The results show that: The FDS simulation method can effectively simulate the thermal runaway fire in the storage of vehicle power battery pack. The heat release rate and the smoke spreading process are similar to the test process. Through the simulation of the temperature field distribution in the modular thermal runaway scenario, the fire can be controlled in the compartment of the box through effective separation measures and will not affect other spaces and cause serious disasters. The response of different sensors was tested. The 32.8 kHz ultrasonic sensor still collected the thermal runaway state of the battery earlier, significantly earlier than the image and smoke sensors, and the ultrasonic sensor had a more significant detection effect in a relatively closed space.

Key words: decommissioned batteries, detection and early warning, fire separation, ultrasonic detection