They called them Edison Cells. About 1.2 VDC per cell. 1.0 dead. About 1.5 to 1.6 fully charged. Alkaline. Not acid. Big, heavy and kinda very spendy. Bundle them up to get what voltage needed and you would be good to go. Not very efficient weight wise for the wattage provided. But ... they are still used in many applications. HB of CJ (old coot)
Now wondering if they have licked the shorting out problem using very thin close plates? This might reduce the size, weight and cost.