Why are polymer lithium batteries bulging?

Reasons for the bulging of polymer lithium battery 1. The polymer battery cell is overcharged. As mentioned above, when the battery cell voltage exceeds 4.2V, there should be a series of chemical reactions inside the gas, which will be repeated for a long time. Slightly overcharged, the gas inside the cell gradually accumulates and the cell swells. Therefore, we must ensure that the battery core cannot be overcharged during use and testing. When designing the charging circuit and protection board, we should fully consider the charging voltage not to exceed 4.2V. 2. The cell is over-discharged. When the cell is over-discharged (voltage<2.0V) and stored for a long time, due to the electrolysis reaction inside the cell, the copper in the anode current collector decomposes, and gas appears inside the cell. The important reaction process of the gas is as follows: 3. The polymer cell is affected by high temperature, and the cell is inflated in a high temperature environment as listed above. Most of the time, the cell is stored at a higher temperature (such as 50C) for a long time. The temperature will accelerate some chemical reactions inside the cell, forming gas, especially when the cell is fully charged or slightly overcharged, the effect of high-temperature storage is more obvious. Therefore, it is necessary to prevent the cell from being exposed to high temperatures for a long time. storage. The correct approach to polymer lithium batteries is summed up. The most important reminder for the charging and discharging problems of lithium battery packs in use is 1. Charge according to the standard time and procedure, even if it is the first three times; 2. When the machine appears When the battery is too low, you should start charging as soon as possible; 3. There is no special way to activate the lithium battery. The lithium battery will naturally activate during the normal use of the machine. If you insist on using the first three 12-hour long charge activation methods that have been circulated, it will actually not be effective; Statement: Some pictures and content of the articles published on this site are from the Internet. If there is any infringement, please contact to delete the previous article: Lead acid What are the differences between batteries and lithium batteries?