Developer, ReVolt Technology Ltd is ready to bring to market new zinc-air batteries that can store three times the energy of lithium-ion batteries, by volume, while costing only half as much. The first plan to sell small "button cell" batteries for hearing aids starting next year and to incorporate its technology into ever larger batteries, introducing cell-phone and electric bicycle batteries in the next few years. It is also starting to develop large-format batteries for electric vehicles. The MIT site Technology Review has more info about the tecnology and some of the hurdles zinc-air storage needs to overcome.