more (at source): Improved capacity is thanks to the addition of a component that uses oxygen drawn from the air during discharge, replacing one chemical constituent used in rechargeable batteries today. Not having to carry the chemicals around in the battery offers more energy for the same size battery. Reducing the size and weight of batteries with the necessary charge capacity has been a long-running battle for developers of electric cars.

The STAIR (St Andrews Air) cell should be cheaper than today's rechargeables too. The new component is made of porous carbon, which is far less expensive than the lithium cobalt oxide it replaces.

Whoever thought we would be getting energy from air?