What is the internal structure and working principle of lithium batteries?

1. The internal structure and working principle of the lithium battery. The ignition point of these two electric vehicle spontaneous combustion incidents is the power lithium ion battery. The power lithium ion battery has always been a component that car owners carefully supply, whether it is daily charging and discharging, and then Taking some bad roads, everyone pays great attention to the most expensive power lithium-ion battery in the whole car. All lithium batteries are chemical batteries. The principle of chemical batteries is the flow of electrons between the positive electrode and the negative electrode. There is a separator and electrolyte between the positive electrode material of the lithium battery. If the positive and negative poles of a battery are short-circuited, they will heat up. If the heat is heated to a certain extent, the electrolyte will leak. Then the battery’s cathode material lithium will be exposed to oxygen, and lithium is a very active metal. When metal is exposed to the air, it will react with oxygen violently and ignite and explode. A separator with many pores will be added to the battery to prevent short circuits. A good separator can also automatically close the pores when the battery temperature is too high, so that lithium ions cannot pass through and prevent danger. 2. A slight negligence will cause fire or explosion. Although there is a diaphragm to isolate lithium ions and oxygen molecules, if the battery is impacted by external force or the battery is not made fine enough, small impurities pierce the diaphragm paper, and internal short-circuit phenomenon will occur. , Resulting in fire or explosion. In addition, an external short-circuit phenomenon may occur during actual use. After a short-circuit occurs, the battery temperature will rise sharply, causing the electrolyte to vaporize, bursting the battery casing, and the lithium ion encounters oxygen and catches fire. If there is no problem with the battery quality, but the battery is overcharged. In the case of overcharge, many needle-like lithium metal crystals will appear on the negative electrode, and these crystals will also pierce the diaphragm paper, causing an internal short circuit, causing fire and explosion. In addition, high temperature, impact, and puncture may damage the diaphragm. In the case of an internal short circuit, the problem often occurs suddenly. Because of quality problems or improper use, a short circuit has occurred inside the battery, and the heat of the battery is slowly accumulating, but you can't notice it. When the heat accumulates to a certain level and reaches a critical point, it will cause a fire or explosion without any warning before. Disclaimer: Some pictures and content of articles published on this site are from the Internet. If there is any infringement, please contact to delete. Previous article: Which parts of the lithium battery? What are its advantages?