During the discharge, the lead dioxide in the anode and the spongy lead in the cathode react with the sulfuric acid in the electrolyte to form lead sulfate and water, eleasing the chemical energy into olectrical energy.
When charged, the lead sulfate at the Yin and Yang Poles is converted into lead dioxide and spongy lead, respectively, and the electrical energy is converted into chemical energy for storage. But at the end of charging or over-charging, the over potential of the chemical reaction between the cathode and the node increases, the negative electrode produces hydrogen and the positive electrode produces oxygen, the side reaction of oxygen will dominate, based on the positive electrode charging state reaches 70% when oxygen begins to be produced, when the charge state of the negative electrode reaches 90%, the mechanism of hydrogen production begins. Through the optimized design and the use of PB-CA multi-element alloy, the oxygen produced on the positive electrode can react with the living matter on the negative electrode to produce water, and the internal circulation of oxygen can be realized, at the same time, the over potential of hydrogen evolution is increased, so that the charge state of the negative electrode is always less than 90%, and the hydrogen evolution is well restrained.
