Characteristics of lithium-ion battery fire
1 Rapid fire speed and long duration
According to NFPA (National Fire Protection Association) experiments, the fire spreads rapidly within the power lithium-ion battery module in just a few seconds and lasts for about 27 minutes.
2 High combustion temperature
Lithium-ion battery combustion is characterized by high temperatures, according to NFPA experiments, the maximum temperature outside the battery in the combustion can reach 283-1090 degrees Celsius, the temperature inside the battery can reach 572-1121 degrees Celsius, such high temperatures are enough to ignite the battery module inside the car and other combustible materials, resulting in a larger fire.
3 Extinguishing Difficulty
For lithium batteries, most of the combustion reaction occurs inside the battery shell, the battery shell impedes the role of extinguishing agents, in practice, lithium battery fire extinguishing time is often more than the firefighters carry oxygen cylinders for oxygen supply time, the firefighters pose a certain threat to personal safety.
4 long time spontaneous combustion or even explosion
Lithium batteries are capable of spontaneous combustion, followed by an explosion due to overheating. The causes of overheating include electrical short circuit, rapid discharge, overcharging, manufacturing defects, poor design or mechanical damage. Overheating can lead to the process of "thermal runaway", which is most likely to occur during the charging and discharging process of a battery, i.e., an exothermic reaction within the battery that causes the internal temperature and pressure of the battery to rise at a very rapid rate, thus wasting energy.
Due to the lithium-ion battery itself has a certain internal resistance, in the output of electrical energy for electric vehicles to provide power at the same time will produce a certain amount of heat, making their own temperature becomes high, when their own temperature exceeds its normal operating temperature range will damage the entire battery life and safety.
Lithium batteries have a special danger, in the fire manifested as a chain of internal decomposition reaction, so the face of lithium battery fire using the correct fire extinguisher is very important!
Fire extinguishing treatment for lithium batteries allows us to do a little operation:
1. If the small battery suffered a small fire, the flame did not spread to the high-pressure battery part, you can use carbon dioxide or ABC dry powder extinguishers to extinguish the fire. You can also use the hose to flush water for a period of time to let the flame as well as the battery to achieve cooling.
2. If it is a high-voltage battery, a very large open fire, there are a lot of smoke these, and can clearly see the battery or equipment in the fire bending, twisting, damage, in short, it is becoming out of shape, or suspect that the battery problem. Then this time to fight the fire will need to use a lot of water, and must be guaranteed to cut off all the electricity in the case of fire extinguishing, extinguishing the fire when the amount of water can not be too little, the fire fighting water to have enough.
3. When checking the fire thoroughly, do not contact with any battery parts and high voltage parts with bare hands, and always use insulated tools for checking. To prevent poisoning or electrical conductivity.
4.Battery fires can take up to 24 hours to fully extinguish. Using a thermal imaging camera will ensure that the high voltage battery is completely cooled down before the incident is over. Without a thermal imaging camera, the battery must be monitored for re-ignition. Smoking indicates that the battery is still hot, and monitoring should be maintained until at least an hour after the battery stops smoking.