What causes lithium battery fires?

The essence of a lithium battery fire is that the heat in the battery fails to be released according to the design intention, causing the internal and external combustion materials to ignite and then catch fire . The main causes are external short circuit and high external temperature. and internal short circuit. Here are the specific reasons why lithium batteries are prone to catch fire: Internal short circuit: due to abuse of the battery, such as dendrites caused by overcharging and overdischarging, dust of impurities in the process of battery production, etc. , will deteriorate and pierce the diaphragm, causing a micro short circuit. The release of electrical energy will cause the temperature to increase, and the chemical reaction of the material caused by the temperature increase will widen the short circuit path and form a more short circuit current.important. This mutually cumulative and reinforcing damage will result in thermal runaway. External short circuit: A long-term external short circuit usually causes the weak circuit connection points to burn out and rarely causes thermal runaway of the battery. High external temperature: Due to the structural characteristics of lithium batteries, various reactions generate a large amount of heat. The diaphragm melts, causing an internal short circuit, and the release of electrical energy increases heat production. Due to this cumulative and mutually reinforcing destructive effect, electrolyte is ejected, resulting in combustion and fire.