Reservo Dry-charged batteries have electrolyte fluid. However, the electrolyte fluid contained in dry-charged batteries has a small lead content, making it evaporate less easily and hence is more efficient. A dry-charged lead acid batteries is formed by removing the electrolyte through aperture and then sealing the aperture with a sealing plug with a valve having a rubber valve (check valve) provided therein. Reservo Dry-charge comes with 6V and 12V models with an acid pack to fill activated during first use. No maintenance is required during long storage periods