The two most important points of the lithium-ion battery packaging process

Many people think that welding lithium-ion battery cells together is not a lithium-ion battery? Isn't it easy to do? The lithium-ion battery market is gradually becoming more and more widely used. Many businesses who are optimistic about the lithium-ion battery industry have begun to purchase and sell. However, in order to obtain more profit margins, assembling lithium-ion batteries has become the best choice for major businesses . It is easy to assemble a lithium-ion battery, but if you want to make it well, it will not be as simple as your friends think it will be used for a long time! Because the lithium-ion battery market is in the development period, the individual assembly and production technology cannot be perfected. For safer processing and production, systematic technical learning is indispensable. To know more lithium-ion battery technology, you can pay attention to the public account. There are two important points in assembling a lithium-ion battery pack: 1. The battery cell 2. The spot welding is not enough. Either the battery life is very short, or the cruising range decays quickly, and the consequences of false welding and missing welding. It's more serious. Use three battery cells to assemble the battery to fool people, and make their so-called lithium-ion batteries that can only be used at the time, and even lead-acid batteries can’t do it. If they use good batteries to make batteries that are not as good as our ordinary batteries. For a long time, they don’t care if you can use it for a long time, but you didn’t discuss it. If you really want to make lithium-ion batteries well, safe and stable, long life, slow decay, and you don’t need three batteries, it’s not that simple. Before lithium batteries are assembled into battery packs, they often have to go through the precise matching of voltage/resistance/capacitance in order to achieve the maximum effect of each cell; the result of no precise pairing is that the battery pack will use the worst cell (or That string) external output, yes, it is the barrel effect. Many people think that the batteries they bought are well-distributed by distributors (some self-proclaimed 'manufacturers'), and they don't need to be tested by themselves, they can be installed directly. Leaving aside the full inspection, at least you have to take random inspections, otherwise the mentality of quick success will only make you continue to do after-sales for the battery in the future. When assembling any battery pack, don't take the mentality of cutting corners. The auxiliary materials must be used, and they must go through a series of steps such as capacity classification, sorting, spot welding, inspection, and aging. 16-channel 5V10A lithium-ion battery detection sub-capacity equalizer application example The inconsistency of lithium-ion battery parameters mainly refers to the inconsistency of capacity, internal resistance, and open circuit voltage. If inconsistent batteries are used in series and used together, the following problems will occur: 1) Capacity loss, the single batteries form a battery pack, and the capacity conforms to the 'barrel principle'. The capacity of the worst battery determines the entire battery pack ability. In order to prevent the battery from overcharging and discharging, the logic of the battery management system is set up as follows: when discharging, when the lowest cell voltage reaches the discharge cut-off voltage, the entire battery pack stops discharging; when charging, when the highest cell voltage touches the charge cut-off voltage To stop charging. Take two batteries in series as an example. One battery has a capacity of C, and the other has a capacity of only 0.9C. In a series connection, two batteries pass the same amount of current. When charging, the battery with small capacity must be fully charged first, and the charging cut-off condition is reached, and the system will not continue to charge. When discharging, a battery with a small capacity will inevitably emit all available energy first, and the system will stop discharging immediately. In this way, batteries with small capacity are always fully discharged, while batteries with large capacity always use part of the capacity. Part of the capacity of the entire battery pack is always in an idle state. 2) Life loss. Similarly, the life of the battery pack is determined by the cell with the shortest life. It is very likely that the cell with the shortest life span is the cell with a small capacity. Small-capacity batteries are fully charged and discharged every time, and the output is too strong, which is likely to reach the focus of life first. When the battery cell's life ends all the time, a group of battery cells welded together will die. 3) The internal resistance increases, the same current flows through different internal resistances, and the cells with large internal resistance generate more heat. The battery temperature is too high, causing the deterioration rate to accelerate, and the internal resistance will further increase. Internal resistance and temperature rise form a pair of negative feedback, which accelerates the deterioration of high internal resistance cells. 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: What factors affect the life of lead-acid batteries?