Abstract : The capacity and long life of gel electrolyte batteries is connected with gas recombination producting PbO2 and Pb electrode. We were prepared with sulfuric acid gel electrolyte to know gel characteristics per density to assemble valve regulated lead-acid(VRLA) batteries. We studied by measuring electrolyte dispersion using Brewster-angle microscope(BAM), charge-discharge cycle and electrode structure using scanning election microscope(SEM) per electrolyte density. As a results, sulfuric acid density 1.210 was excellent gel dispersion in sol condition, electrode condition after fifty cycles in this study.