Abstract: A charge-retention battery includes in a cover a plurality of reservoirs corresponding to the cells of the battery. The cover has the lateral dimensions of a conventional battery case and shortened sides. Minimum length transfer tubes run between the reservoirs and the cells, through the lid of the battery. The tubes fit between adjacent battery plates, with only slight modification of the plates required. To remove electrolyte from the cells and prevent self-discharge, inert gas under pressure is fed to the cells. The gas forces the electrolyte from the cells, through the transfer tubes and into the reservoirs. To place battery in service, the gas is released and electrolyte flows from each of the reservoirs, through the transfer tubes to the associated cells.

Abstract: An electric storage battery is provided wherein the electrolyte is transferred under pressure of an inert gas to a reservoir for containment during periods of non-use of the battery. The inert gas also serves to blanket the battery electrodes during such non-use periods, preventing oxidation while not exposed to electrolyte. Thus, there is no discharge of the battery during even prolonged periods of non-use and on return of the electrolyte to the battery cells the battery is in ready condition for use at relatively full charge.