Lithium-ion batteries are usually composed of a metal coil and a flammable lithium-ion liquid. Small metal fragments are floating in the liquid. The contents of the battery pack are under pressure. Therefore, if a piece of metal fragments pierce the separator that adheres to the object, or the battery is pierced, high temperature will occur, which will react strongly with water in the air, and sometimes cause the lithium battery to catch fire. .

  Lithium battery packs provide high power output with minimal weight. The battery pack is designed to be lightweight, which means that there is a thin partition between the battery and the thin case. The partition wall and coating are very fragile and easily pierced. If the battery is damaged, a short circuit will occur. A spark can also ignite highly active lithium. Another possibility is that the lithium battery is heated to an uncontrollable degree. Here, the heat of the contents exerts pressure on the battery, which may cause the lithium battery to explode.

  The method to prevent the fire or explosion of lithium-ion batteries must first find out the thermal explosion mechanism of lithium-ion batteries. The thermal explosion mechanism is: the battery is subjected to thermal shock, overcharge, overdischarge, short circuit, vibration, squeeze and other misuse conditions. There will be a chemical interaction between the internal active material and the electrolyte and other components. The electrochemical action generates a large amount of heat and gas, causing the battery to heat up. Assuming that the heat generation rate inside the lithium-ion battery is greater than the heat loss rate, the system The reaction temperature will continue to rise, and when the heat and internal pressure accumulate to a certain level, it will cause the battery to burn or explode.

  1. Add flame retardant to the existing electrolyte. However, in order to achieve the ideal flame retardant performance, a large amount of flame retardant must be added to the electrolyte, so that the ionic conductivity of the electrolyte decreases, thereby affecting Lithium battery's electrochemical performance and energy density.

  2. Realize maintenance by adding a dedicated maintenance circuit, such as: to prevent overcharging of lithium-ion batteries, install a PTC polymer switch or explosion-proof safety valve in the battery safety helmet.

  3. The thermal stability of lithium batteries is related to the type of cathode material and electrolyte. By optimizing the synthesis conditions and improving the synthesis method, a positive electrode material with good thermal stability was synthesized.

  4. Weak oxidation on the surface of carbon materials, such as reduction, doping, surface modification, etc.; or use spherical, fibrous carbon anode materials to improve the thermal stability of lithium batteries.

  In order to better utilize the advantages of lithium battery to prevent fire incidents For huge losses, it is necessary to investigate the real cause of the fire in order to make preventive measures, use it correctly, and prevent losses. Standardize soil conservation and sprinkle water for conservation.