Gel battery belongs to a development classification of lead-acid battery. The simplest way is to add a gelling agent to sulfuric acid to make the sulfuric acid electro-hydraulic become colloidal. Batteries with colloidal electrolytes are usually called colloidal lead-acid batteries (VRLA), which are batteries whose electrodes are mainly made of lead and its oxides, and the electrolyte is sulfuric acid solution. In the charged state of the lead-acid battery, the main component of the positive electrode is lead dioxide, and the main component of the negative electrode is lead; in the discharged state, the main component of the positive and negative electrodes is lead sulfate.