The liquid metal battery is a technology suitable for grid-scale electricity storage. The liquid battery is the only battery where all three active components are liquid when the battery operates. These batteries improve the integration of renewable resources into the power grid as well as the reliability of an aging grid. These high-capacity batteries consist of molten metals that naturally separate to form two electrodes in layers on either side of the molten salt. A zinc-air battery stores electricity from renewable sourcesby converting zinc oxide to zinc and oxygen. In order to discharge stored electricity when required, the battery converts the electrochemical energy from the zinc by. Besides the common advantage of all metal-air batteries – high energy density – iron–air rechargeable batteries have additional benefits, such as low cost, an abundance of raw material (iron oxide), safety and recyclability. The aluminum-air battery technology is based on the reaction of oxygen in the air with aluminum. Because of their massive energy density, these batteries are perfectly suitable for.