metal oxygen battery

Metal-air batteries are based on a technology that has been known for years and is experiencing a renaissance. In metal-air batteries, the anode consists of a metallic powder, while the cathode is formed by the oxygen in the air. Between the two electrodes there is a liquid or solid electrolyte in which metal ions transfer the charge from one electrode to the other. The anode can be made of metals such as zinc or aluminum, or alkali metals such as lithium or sodium.

This means that there are zinc-air batteries and aluminum-air batteries, and also sodium-air and lithium-air batteries. Some of the types mentioned can currently only work as primary cells, which are batteries, whereas others work as secondary cells and are rechargeable.

One advantage of metal-air batteries is their high energy density, whose theoretical values can exceed 10,000 Wh/kg. This value applies to lithium-air batteries. Other metal-air cells, such as the zinc-air battery, achieve 500 Wh/kg. The power density is between 300 and 2,000 W/kg and the number of charging cycles between 200 and 1,000. Other advantages are the low weight and that air is available in sufficient quantities.