The battery provides stored energy for 150 hours and costs one-tenth the price of traditional lithium-ion batteries.
The battery works thanks to “reversible oxidation of iron”. While in operation and discharging, the iron rusts under the effect of oxygen in the air – it turns into iron oxide while providing energy in the course of a chemical reaction.
While it is being charged, oxygen is released and it becomes iron again and energy is stored in the process. The battery is charged over the course of several days and is capable of providing energy for 100-150 hours. And the battery’s size is considerable – each block contains 20 cells, each measuring 90 cm by 90 cm.
The cost of a kilowatt hour for a block will amount to no more than $20 – and therefore from 1/10 to 1/4 the cost of lithium-ion batteries.
Form Energy’s CEO previously worked at Tesla – Mateo Jaramillo – and he purchased the patent for the iron-air battery from a U.S. company in Arizona. His investors come from the Breakthrough Energy Ventures Fund backed by Bill Gates and Jeff Bezos as well as the world’s largest steelmaker, ArcelorMittal.
The company’s plans call for a pilot project with a capacity of 300 MW to be brought on stream in 2023 for the Minnesota-based utility Great River Energy. The air battery is a relatively new development – the first company to announce the creation of an air-zinc battery was the Canadian company Zinc8.