Nickel-Zinc Battery

The nickel-zinc battery is a rechargeable cell that pairs a zinc negative electrode with a nickel oxyhydroxide positive electrode, producing zinc oxide and nickel hydroxide as it discharges. Thomas Edison patented an early version of the concept in 1901, and Irish chemist James Drumm later developed it further, with Drumm-type nickel-zinc batteries powering railway cars between Dublin and Bray from 1932 to 1949, though the chemistry struggled commercially for decades afterward because repeated cycling caused the zinc electrode to deform and lose capacity. Modern nickel-zinc cells deliver a nominal voltage of about 1.65 volts, higher than the 1.2 volts of nickel-cadmium or nickel-metal-hydride batteries and close enough to a standard alkaline cell to serve as a drop-in replacement in many devices. Renewed development since the 2000s has addressed the older durability problems, and the chemistry is now marketed for power tools and other high-drain uses partly because, unlike older rechargeable chemistries, it contains no mercury, lead or cadmium.