Summary of Causes of Lithium Battery Explosion and Preventive Measures

Overview of the causes of lithium battery explosion and preventive measures Lithium is the smallest and most vivid metal on the periodic table. Because of its small size and high capacity density, it is deeply loved by users and engineers. However, the chemical properties are too distinctive, which brings high risks. When lithium is exposed to the air, it undergoes a violent oxidation reaction with oxygen. In order to improve safety and voltage, scientists have made it possible to store lithium atoms in materials such as graphite and lithium cobalt oxide. The molecular structure of the data forms a grid of nano-scale micro-storage cells that can be used to store lithium atoms. In this way, even if the lithium battery casing breaks and oxygen enters, the oxygen molecules are too large to fit into the tiny battery, thereby preventing lithium atoms from contacting with oxygen and exploding. Analysis of the cause of lithium battery explosion. Insufficient ability to negative. When the positive position is in the negative part of the lack of ability, or work, no ability to charge part or all of the lithium anode graphite can not penetrate the layer structure, analyze the appearance of the cathode, forming a protrusion When the dendrites are charged next time, the protruding parts of lithium are deposited in a simple form. After hundreds of cycles of charging and discharging, the dendrites will grow up and will eventually pierce the barriers of the paper and cause internal short-circuits. The rapid discharge of cells, a large amount of heat, and the burning gap, constitute a larger short-circuit phenomenon. High temperature will decompose the electrolyte into gas, and carbon dioxide and blank paper will burn, which constitutes an internal pressure that is too large. When the shell of the cell is unacceptable Stress, the cell ruptures. Electrolyte and batteries with excessive moisture content and moisture, when gas appears, lithium can be generated when charging, and lithium oxide can be generated, which will cause the loss of battery capacity, and it is easy to overcharge the battery and process natural gas, and the water breakdown voltage is low, and the charging is easy Decomposition produces gas. When the series of gas generated can make the internal pressure of the battery unacceptable, the battery will rupture. The internal short circuit is due to the internal short circuit phenomenon, the core of the large current discharge, a large amount of heat, the combustion gap, and a larger short circuit phenomenon. Therefore, the core will undergo high temperature and the electrolyte will decompose into gas, which constitutes the internal pressure. The core shell cannot accept pressure, and the core will burst. When gluing and laser welding, heat conduction passes through the active ears of Shell, so that the temperature of the active ears is high. If the ears and gaps on the front of the adhesive paper are not separated, the hot active ears will burn the paper or shorten the gap, forming an internal short circuit. , Constitute blasting. High-temperature adhesive tape covers the cathode ears. When customers spot welding on the anode ears, heat is transferred through the anode ears. If the high-temperature adhesive paper is not adhered firmly, the heat on the anode ears will burn out the gaps, forming an internal short circuit and blasting. The bottom glue does not completely cover the bottom. When the customer spot-welds the aluminum-nickel composite tape at the bottom, a lot of heat will occur on the bottom shell wall and the core of the bottom of the conductive rod. If the high-temperature adhesive paper does not completely cover the gap, the gap will burn. An internal short circuit is formed, which constitutes blasting. When the rechargeable battery is charged, the excessive release of lithium in the positive electrode will cause the structure of the positive electrode to change, and the excessive release of lithium just cannot penetrate into the negative electrode, and it is only processed lithium, the appearance of the negative electrode, when the voltage reaches more than 4.5v, the electrolyte will decompose A large amount of gas is present. All this can be explosive. External short circuit The external short circuit may be caused by improper operation or abuse. Due to the external short circuit, the battery discharge current is large, which will heat the battery, and the high temperature will shorten the gap within the cell or completely destroy it, forming an internal short circuit, thus exploding. Maintenance measures: if the overcharge voltage of the lithium battery is higher than 4.2v, secondary use will begin to appear. The greater the pressure, the greater the risk. When the voltage of a lithium battery is higher than 4.2v, less than half of the lithium atoms remain in the anode data, and the battery often collapses, thereby permanently reducing the battery's capacity. 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 post: What are the differences between lithium batteries and lead-acid batteries?