 Nevertheless, Edison's battery achieved great success in other applications such as electric and diesel-electric rail vehicles, providing backup power for railroad crossing signals, or to provide power for the lamps used in mines.Until the late 1950s, the zinc–carbon battery continued to be a popular primary cell battery, but its relatively low battery life hampered sales.The Canadian engineer Lewis Urry, working for the Union Carbide, first at the National Carbon Co. in Ontario and, by 1955, at the National Carbon Company Parma Research Laboratory in Cleveland, Ohio, was tasked with finding a way to extend the life of zinc-carbon batteries.