How to prevent lithium batteries from burning and exploding?

How to prevent lithium battery explosion Lithium is the smallest and most vivid metal on the periodic table. Because of its small size and high capacity density, it is well received by customers and engineers. However, the chemical reaction is too active and it brings a high risk. 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 these data forms a nanoscale microbattery that can be used to store lithium atoms. In this way, even if the battery casing breaks and oxygen enters, the oxygen molecules are too large to fit into the tiny battery, so lithium atoms will not come into contact with oxygen, thereby preventing its explosion. This principle of lithium batteries enables people to achieve safety while achieving high capacity density. When a lithium battery is charged, lithium atoms lose electrons and oxidize to lithium ions. Lithium ions swim to the negative electrode through the electrolyte, enter the negative electrode storage unit, obtain electrons, and the electrons are reduced to lithium atoms. When unloading, the whole process is reversed. In order to prevent the short circuit caused by the direct contact between the positive electrode and the negative electrode of the battery, many small holes of diaphragm paper are added to the battery to prevent short circuit. A good diaphragm paper can also automatically close the pores when the battery temperature is too high, so that lithium ions cannot pass through, so as not to waste time and prevent risks. Safeguard measures The overcharge voltage of lithium batteries is higher than 4.2v, and secondary uses will begin to appear. The greater the pressure, the greater the risk. When the voltage of the 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 capacity. If the battery is continuously charged, subsequent lithium metal will accumulate on the surface of the negative electrode, because the negative electrode storage chamber is already full of lithium atoms. These lithium atoms grow dendrites from the surface of the negative electrode to the direction of lithium ions. These lithium crystals will pass through the diaphragm paper, shorting the anode and cathode. Sometimes a short circuit occurs before the battery ruptures, because during the overcharging process, the electrolyte and other information will decompose to produce gas, causing the battery case or pressure valve to expand and break, allowing oxygen to enter and reacting lithium atoms accumulate on the negative surface, and then explode. Therefore, when charging a lithium battery, a voltage upper limit must be set to take into account the battery's life, capacity and safety. The most ideal charging voltage upper limit is 4.2v. Lithium battery discharge must also have a lower voltage limit. When the battery voltage is lower than 2.4v, some data will be damaged at the beginning. And because the battery will self-discharge, the longer the voltage, the lower it is. Therefore, it is best not to stop the discharge to 2.4V. During the discharge from 3.0v to 2.4v, the lithium battery can only release about 3% of its capacity. Therefore, 3.0v is the ideal discharge cut-off voltage. When charging and discharging, in addition to voltage constraints, current constraints are also necessary. When the current is too large, lithium ions have no time to enter the memory cell and will accumulate on the data surface. When these lithium ions gain electrons, they will crystallize lithium atoms on the surface of the data. This is the same as overcharging and poses a certain risk. If the battery box is broken, it will explode. Therefore, the maintenance of lithium batteries should include at least three aspects: the upper limit of the charging voltage, the lower limit of the discharge voltage, and the upper limit of the current. In addition to the lithium battery, the general lithium battery pack also has a maintenance board. The maintenance board is important to provide these three maintenance. However, the maintenance of these three maintenance boards is obviously insufficient, and explosions of lithium batteries still occur frequently worldwide. In order to ensure the safety of the battery system, it is necessary to conduct a more detailed analysis of the cause of the battery explosion. 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: How to determine the battery capacity?