Edison Nickel Iron Battery Section views, 1918

Although the Nickel Iron battery had been invented, patented and abandoned in Europe in the 19th century, Edison developed the technology and took out US and German patents for it in 1901. The projected use was for electric vehicles, as the energy density was higher than lead acid batteries of the time. These section models and drawings were done to promote the technology. 

 Unfortunately electric vehicles soon went out of production but the technology found uses for forklifts, standby power units and similar as the battery is very robust and long-lived, tolerating misuse like constant charging, overcharging, heavy discharge rates and even short circuits. Edison manufactured them till 1972, when the technology was sold to Exide Battery who discontinued them shortly afterwards. There has been recent interest in the technology as a storage battery for solar power.

Thanks, Rolf!