The Zinc Evonyx car fuel cell oxidizes zinc with oxygen from the air. A hydrogen fuel cell oxidizes hydrogen with oxygen from the air. In both processes, the energy released in the oxidation is converted to electricity and heat.
Fuel cells are generally defined by chemists as electrical cells designed to convert the energy from the combustion of fuels such as hydrogen and carbon and hydrogen containing molecules into electrical energy. Are we combusting the Zinc? Many metals burn in air, Zinc included. I think we could extend the fuel cell definition to Zinc, Aluminum etc., and other metals that burn in air.
The information at the companies website suggests that the oxidized zinc can be easily removed from the cell, and a new zinc fuel bar or strip inserted to continue the trip, which is analogous to going to the gas pumps and fueling up. In a normal battery, reactions would occur at both cathode and anode that have to be reversed to recharge the battery. This is not the case with this cell, because the only thing that appears to be happening is the oxidation of Zinc. The anode and electrolyte remain chemically the same, and act only to transfer electrons.
Based on the above, I would call the Zinc electrical cell powering the car, a "zinc fuel cell". Having said this, it could also be used as a rechargeable battery by reversing the oxidation of zinc at the cathode,...thus recharging it. |
