What causes the active material of UPS battery to fall off?

The reason why the active material of UPS battery falls off The active material of UPS battery plate is lead dioxide and porous metal lead. In long-term use, the battery continues to charge and discharge the active material of the electrode plate to undergo oxidation-reduction reaction, the volume changes, expansion and contraction are repeated, and the active material gradually becomes soft and falls off, especially the positive plate is more obvious, which should be regarded as normal. It is an abnormal phenomenon that some batteries have a large amount of active material shedding in the early stage, which is characterized by: decreased capacity, increased temperature, turbid electrolyte, and large outgassing. ①The temperature and density of the electrolyte are too high during charging; once the active material of the negative plate encounters the high-density electrolyte, the active material will fall off after several cycles of charging. ②When the UPS battery is installed improperly and driving, it will be impacted due to the bumps of the car, so that the frame of the pole plate is likely to be broken and the active material will be accelerated to fall off. ③The charging current is too large, the time is too long, the temperature is too high, there is a large amount of hydrogen, oxygen gas, and excessive impact active materials; often the overcharged active materials are excessively oxidized, loose, the grid is corroded, and the ability to carry active materials is lost. ④ The active material falls off. It is important that the active material lead dioxide on the positive plate falls off. In severe cases, the electrolyte is turbid and brown. When the UPS battery is charging, there are brown substances rising from the bottom, the voltage rises too fast, the boiling occurs prematurely, and the relative density rises slowly; the voltage drops too fast and the capacity decreases during discharge. ⑤The chemical change inside the UPS battery with high current discharge for a long time is more rapid, which causes the bending and deformation of the electrode plate, which makes the active material easily fall off from the skeleton; in addition, when the specific gravity of the electro-hydraulic and the temperature of the electro-hydraulic are too high, the sulfuric acid will affect the skeleton and The corrosive use of the active material is great, and the reduction of its mechanical strength will also accelerate the shedding of the active material. ⑥ The negative plate of the UPS battery is frozen. UPS battery plate processing generally adopts the drying method of hot air circulation. The active material on the surface of the plate is dried first, and the active material on the inner layer is dried afterwards. The temperature in the warehouse where the polar plates are stored in the cold atmosphere in winter is very low, and the negative plates will be frozen if they are not fully dried. ⑦The lead dioxide itself is not firmly bonded to each other, and lead sulfate is generated during discharge, and it is restored to lead dioxide during charging. The molar volume of lead sulfate is about 2 times that of lead dioxide. The volume of the active material expands during discharge and shrinks during charging. Repeated contraction and expansion will gradually loosen the bond between the lead dioxide particles and easily fall off. 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: Compared with lead-acid batteries, what are the advantages of lithium iron phosphate battery packs?