Abstract: Take the lithium-ion phosphate battery for electric vehicles as the research object, to explore the changes of voltage and temperature of lithium-ion battery of electric vehicle when it is used as ignition source and summarize its characteristics of residue patterns, the main abuse ways of mechanical damage, electrical damage and thermal damage were used in the experiment. The results show that the higher the SOC value is, the greater the damage is, the worse the integrity of the aluminum-plastic packaging, the richer the color variation, and the more obvious the folds. When the lithium-ion phosphate battery has thermal runaway, it will release much energy for a long time.

Key words: lithium-ion battery, thermal runaway, pattern characteristics, fire investigation