Abstract: The lithium battery puncture experiment platform was built, to simulate the electric vehicle accident scene of the battery system in collision. The fire behaviors of lithium iron phosphate battery and ternary lithium battery by puncture were analyzed. Also the fire extinguishing experiment was carried out on a lithium iron phosphate battery module. As the result shows, the lithium iron phosphate battery got longer burning time and weaker flame intensity, while the ternary lithium battery got shorter burning time and higher flame intensity; it was effective for the dry powder fire extinguishing agent to extinguish the lithium iron phosphate battery fire; however, it cannot prevent the reactions occurring inside the battery so that the risk of re-ignition is high. The fire rescue personnel should pay attention to prevent the re-ignition of the power battery system when handling electric vehicle fire accidents in collision.

Key words: electric vehicle fire, lithium battery fire, puncture, dry powder fire extinguishing agent