The main reason why lithium battery electric vehicles caught fire

In recent years, fires of lithium battery electric vehicles have occurred from time to time. Investigations have shown that overcharging, short circuits of lithium batteries, and the use of inferior chargers are the main reasons for the fires of lithium battery electric vehicles. Once an electric car catches fire, the fire temperature can reach thousands of degrees in just 3 minutes, and the consequences will be disastrous. ●External impacts External impacts can cause damage to the internal structure of lithium battery electric vehicles or damage to the outer shell. In severe cases, the electrodes of the lithium battery will be exposed to the air. Because the lithium battery is inserted into the negative electrode of lithium, it has strong reducibility, which is close to the metal state of lithium. , Once in contact with the air, it will generate heat and smoke, and it will catch fire if it is not controlled in time. ●Internal short circuit During the use of lithium batteries, lithium dendrites will appear due to factors such as ambient temperature and electrode characteristics. The accumulation of lithium dendrites will damage the diaphragm and cause a short circuit between the positive and negative electrodes. Heat concentration will cause spontaneous combustion of lithium batteries in electric vehicles. In addition to the formation of lithium dendrites in the membrane causing internal short circuits, defects in the separator and current collector burrs can also damage the separator and cause internal short circuits. ●Overcharged and over-discharged lithium batteries. Excessive charging of electric vehicles will cause the electrolyte to heat up and analyze the gas. The gas builds up pressure inside the sealed battery, causing the lithium battery to expand. If the diaphragm breaks during the expansion process, the positive and negative electrodes contact will cause a short circuit And caught fire. Similarly, external high-power over-discharge will also cause the internal heating and expansion of the battery, and a damage process similar to that of over-charge will cause fire. ●Charger quality problems The main reason for the fire of lithium batteries in electric vehicles is overcharging. If the battery is qualified, the charger is not qualified. If the power cannot be cut off in time after the overflow, or the charging current is too large, it will simply cause overcharging. At this time, it becomes a fire hazard time. Therefore, the lithium battery charger must be qualified. Disclaimer: Some pictures and content of articles published on this site are from the Internet. If there is any infringement, please contact to delete.