What is the principle of a battery?

The anode (PbO2) and cathode (Pb) in the battery are immersed in the electrolyte (dilute sulfuric acid), and 2V power will appear between the two poles. This is based on the principle of the battery. After charging and discharging, the cathode, anode and electrolyte will generate as follows Change: (anode) (electrolyte) (cathode) PbO2+2H2SO4+Pb---u003ePbSO4+2H2O+PbSO4 (discharge reaction) (lead peroxide) (sulfuric acid) (sponge lead) (anode) (electrolyte) ) (Cathode) PbSO4+2H2O+PbSO4---u003ePbO2+2H2SO4+Pb (charge reaction) (lead sulfate) (water) (lead sulfate) 1. Chemical changes during discharge When the battery is connected to an external circuit for discharge, dilute sulfuric acid is It will react with the active materials on the anode and cathode plates to form a new compound 'lead sulfate'. The sulfuric acid component is released from the electrolyte through the discharge, and the longer the discharge, the thinner the concentration of sulfuric acid. The consumed component is proportional to the discharge amount. As long as the concentration of sulfuric acid in the electrolyte is measured, that is, the specific gravity is measured, the discharge amount or residual electricity can be known. 2. Chemical changes during charging. Because the lead sulfate that appears on the anode plate and the cathode plate during discharge will be decomposed and reduced to sulfuric acid, lead and lead peroxide during charging, the concentration of the electrolyte in the battery gradually increases. That is, the specific gravity of the electrolyte rises and gradually returns to the concentration before discharge. This change shows that the active material in the battery has been reduced to a state where it can be powered again. When the lead sulfate at the two poles is reduced to the original active material, that is It is equal to the end of charging, and hydrogen appears on the cathode plate, and oxygen appears on the anode plate. At the final stage of charging, the current is almost used for the electrolysis of water, so the electrolyte will be reduced. At this time, pure water should be used to supplement it. 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: What are the differences between lithium batteries and polymer lithium batteries?