Why does the maintenance-free UPS battery expand?

Why does the maintenance-free UPS battery swell the battery? There are many reasons for the expansion of UPS batteries, and maintenance-free batteries are generally valve-controlled sealed, which have more opportunities for expansion than ordinary batteries. Let's look at several reasons for using UPS battery expansion: 1. Normal expansion. During the use of maintenance-free UPS batteries, in order to extend the battery life, minimize the number of battery safety valve activations. Therefore, under the internal pressure of the UPS battery, the outer wall will bulge. When there is internal pressure, the safety valve will not open, and the shell will swell normally. As long as it does not exceed the specified swelling range, it is a normal phenomenon. 2. Balanced charging causes bulging of the outer wall. When the maintenance-free UPS battery has just been transferred from the discharged state to the charged state, its internal electrochemical conversion efficiency is relatively high, and there is less oxygen. When the battery is close to a fully charged state, the electrochemical conversion efficiency is reduced, and the oxygen appears to increase, causing the internal pressure of the battery to rise slightly, and the outer wall of the battery also swells. Under normal circumstances, after the battery is fully charged, this swelling will reach equilibrium. 3. Abnormal expansion. Abnormal expansion may be caused by the following reasons: 1. The temperature difference and voltage difference beyond the normal value can also cause the maintenance-free battery to swell. 2. The safety valve is out of control. During the charging process, when the internal gas is too large, the safety valve fails and does not open, resulting in excessive internal pressure and bulging of the outer wall. 3. Excessive charging voltage is the most important reason for the swelling of the valve-regulated sealed lead-acid battery shell. 4. Thermal runaway causes the maintenance-free UPS battery to swell and deform. 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: What factors are related to the battery capacity?