Abstract: Abstract: This paper analyzed the accident investigation process of a blade battery damaged by impingement and then caught fire due to moisture. The location of the fire was determined through video analysis, on-site investigation. The fire cause was identified by the theoretical knowledge of electrical faults, thermal runaway of lithium-ion batteries, remote monitoring data, personnel description and other evidence. The field experiment was used to analyze the formation of the impact hole on the lower guard plate and the hole on the cover plate. Combined with the knowledge of electrical theory, problems of the blade battery were analyzed, and some suggestions were put forward to improve its quality.

Key words: Key words: new energy vehicle, blade battery, impingement and moisture, fire investigation