A battery that stores electricity from wind and solar energy for several days

The development of an Iron-Air battery in the United States that can store electricity from wind or solar power plants for several days at a time, and slowly discharge it to the grid. It will help tackle climate change by reducing the need for fossil fuel power plants, according to technology startup Form Energy, of Massachusetts, US.

The Iron-Air battery is a new class of cost-effective multi-day energy storage systems, which can feed electricity for 100 hours at a cost of 1/10 the cost of lithium-ion, the holy grail of renewable energy technology.

It is made using iron, one of the most common elements on Earth, and works by inhaling oxygen, converting iron into rust, and returning rust to iron. As it takes oxygen and shifts iron back and forth, the battery is charged and discharged, a process that keeps the energy stored for longer. If development continues at a rapid pace, Form Energy hopes the first batteries will power the grid by 2025.

This will solve one of the most common problems facing renewable energy, which is how to cheaply store large amounts of electricity and supply it to the power grid when the sun isn't shining for solar panels or when the wind isn't blowing for the turbines. The electric grid now faces the challenge of how to manage this disparity in supply without sacrificing energy reliability or affordability.

Form Energy claims a new battery system is an answer to this growing problem.

They did an extensive review of all available technologies and ended up reinventing the iron air battery, said Matteo Jaramillo, CEO, and co-founder of Form Energy, in order to improve it for multi-day energy storage for the electric grid.

The company says the battery it is developing will allow countries to fully retire thermal assets such as coal and natural gas power plants.

Jaramillo said, with this technology, we are addressing the biggest obstacle to deep decarbonization: providing renewable energy when and where needed, even during multiple days of severe weather or grid outages.

It would also be cheaper, the company said, using a lithium-iron battery cell using the metals nickel-cobalt, lithium-manganese, and costing up to $80 per kilowatt-hour of storage.

Using an iron, Form hopes to get less than $6 per kWh in terms of metal costs per cell, and package them into a complete battery system to keep the cost under $20 per kWh of energy storage.

Investors in the company include Breakthrough Energy Ventures, a climate investment fund backed by Bill Gates, Jeff Bezos, and others, which also secured funding from steelmaker ArcelorMittal, a global leader in iron ore production.

Form Energy is working with ArcelorMittal to develop iron materials that ArcelorMittal will supply non-exclusively to Form battery systems. The company plans to source the iron locally in the United States, then build batteries near where it is located, including within the American Iron Range in Minnesota for Great River Energy.

Greg Ludkowski, global head of research and development at ArcelorMittal, which will supply the iron, said Form Energy has been leading the development of long-term grid-scale battery storage solutions.

He said, the multi-day energy storage technology they developed holds exciting potential to overcome the problem of intermittent supply of renewable energy.

The company was founded by lithium battery pioneer Yi-Mingqiang, a professor at the Massachusetts Institute of Technology, and Jaramillo, who studied economics before moving into battery technology, including a seven-year tenure at Tesla."The founding team has 100 years of battery experience, Chiang told The Wall Street Journal.

In early 2018, the first small tests of the new battery technology began, and in 2020, they were able to purchase patents for an Arizona-based battery company. The final design will see 20 individual cells assembled into a battery with thousands of batteries assembled together inside the warehouse. Each warehouse will then store enough electricity for a week, and it takes days to fully charge but discharge over 150 hours.

It will be charged by renewable energy plants such as wind and solar during operation, to create a 150-hour buffer when they are not producing energy, thus ensuring a continuous supply of electricity to the grid.