Molten air battery
With support from the National Science Foundation, researchers at George Washington University have created molten air batteries. The scientists used iron, carbon and vanadium boride because of their ability to transfer multiple electrons. These batteries can store three, four and 11 electrons per molecule respectively, giving them 20 to 50 times the storage capacity of a lithium battery, which can only store one electron per molecule of lithium.
Pictured here is a molten air battery configuration: The air electrode (circle, left) and the metal electrode (right) are lowered into the crucible (white cup), then covered with electrolyte, which is then heated until it is molten.
Image credit: William Atkins, the George Washington University