Method of making electric storage batteries

A method of making a Plante lead acid cell which comprises electrolytic formation of the positive plate in a sulphuric acid solution characterised in that the positives in electrolytically unformed or only partially formed condition are assembled with negative plates and separators into the battery container, the container filled with sulphuric acid electrolyte and an amount of a corroding agent selected from the group consisting of nitric acid and nitrates having a powerful corrosive action on lead under anodic conditions and reducible under the final cathodic condition at the corresponding negative plate to ionic species which do not interfere with the cell reactions, is incorporated into the cell, such as to convert the lead surface to an extended surface area and provide a sufficient mass of lead dioxide at the extended surface, and subjecting the positive plates to anodic conditions so as to convert the lead surface to an extended surface area and provide a sufficient mass of lead dioxide at the said extended surface, the treatment being for a time sufficient under the cathodic conditions at the negative plates, to convert all of the said corroding agent to the non-interfering ionic species.