New Lithium-Air Battery Survives Hundreds of Cycles

Batteries supply electrons by undergoing reversible chemical reactions. That has meant that all the reactants have to be inside the battery, which adds to its weight and volume. Lithium-air batteries could potentially change that situation.

At one electrode, they have pure lithium metal rather than a lithium-containing chemical. At the other, the lithium reacts with oxygen in the air. When the battery is charged, this reaction is reversed, and the oxygen is returned to our atmosphere.

Source: arstechnica.com