Editorial Feature

Iron-Air Batteries: A New Class of Energy Storage

Iron-air batteries are an innovative, exciting development in high-performance energy storage. This article will look at what this technology means for the battery industry and modern society, and the technological solutions provided by Form Energy.

Iron-Air Batteries: A New Class of Energy Storage

Image Credit: Krisana Antharith/Shutterstock.com

Lithium-Ion Batteries: A Green Technology Not Without its Limitations

The impact of modern industrialized society on the environment has become a crucial issue in recent decades.

Fossil fuel exploitation and use in energy generation and heavy industry lead to greenhouse gas emissions, a primary driver of climate change and rising global temperatures.

Renewable energy generation technologies, such as photovoltaic solar cells and wind turbines, electric vehicles, hydrogen-based technologies, and energy storage devices, have all received intense research focus.

Technological developments have accelerated the move toward a post-carbon economy over the past decades.

The rapid electrification of the global electric system, heavy industry, and transportation requires high-performance, reliable, safe, and durable green energy storage technologies. Lithium-ion battery technology has emerged as a forerunner in energy storage.

Lithium-ion batteries are rechargeable, possess high energy efficiency, long life spans, charge faster than conventional rechargeable batteries, have a high energy density, have high charge-discharge cycles, and are small and light.

While lithium-ion batteries have distinct advantages, they also have several critical drawbacks. They are expensive to manufacture, have safety hazards, such as susceptibility to heat, which can cause them to catch fire, and are susceptible to aging effects and deep charge phenomena.

Sustainability and environmental issues are also associated with this battery technology's manufacture. Lithium-ion batteries use rare metals such as nickel and cobalt, and mining critical metals like lithium is a key environmental problem. Growing demand for batteries has increased the cost of rare metals.

Entering the Energy Storage Industry’s “Iron Age”

Lithium-ion batteries are used in many consumer goods, from electric vehicles to smartphones. However, this battery technology is insufficient for the global electric system, where output is measured in megawatts. The electrification of renewable energy grids requires new energy storage technology.

Developing new energy storage solutions based on different metals and materials is currently a critical focus in battery technology research.

One alternative technology, which has recently received much attention, is iron-air batteries. Iron-air batteries are not new, first developed in the 1960s by NASA.

This technology has the potential to overcome several key issues with lithium-based batteries. Iron is the fourth most abundant element on Earth, which overcomes a significant problem with using lithium: the element’s rarity. The use of iron curtails the extensive use of water in lithium mining and groundwater contamination.

Iron-air batteries can provide energy grids with reliable, safe, efficient, and longer-term energy storage capabilities than conventional technologies. This attractive technology has the potential to revolutionize grid-scale energy storage.

Form Energy’s Iron-Air Battery Solutions

Form Energy is a Massachusetts, US-based energy storage and battery technology company developing and providing innovative iron-air battery technologies which can help address the demands of the global electric system.

The company’s flagship commercial product is a washing machine-sized iron-air battery. Technology development is supported by $760 million of funding and the construction of a new manufacturing facility in West Virginia in the US. The company hopes that the first iron-air batteries will enter production in 2024.

The Technology

Each unit holds approximately 50 iron-air cells, surrounded by an electrolyte.

Key to their operation is the principle of “reverse rusting” wherein the cells “breathe” in air. In this process, iron is transformed into iron oxide, producing energy. The reaction can be reversed by applying a current and converting the iron oxide back into iron.

While lithium-ion batteries only provide about four hours of energy storage capacity, iron-air batteries could provide up to one hundred hours of storage, which is around four days. Therefore, iron-air batteries can act as a bridging technology during energy gaps, such as cloudy days, which would otherwise limit solar power plants.

Iron-air batteries do have one disadvantage compared to lithium-ion batteries, however. They are big and recharge slowly. Form Energy envisions that the technology will be used in blocks, providing the capability to handle long load times, with lithium-ion batteries handling spikes in demand.

Form Energy’s battery technology uses safe, abundant, and sustainable materials: iron, water, and air. The optimized energy storage solutions provided by Form Energy have the potential to be cost-effective and cost-competitive with legacy power plants, making cheap, renewable energy available for use year-round.


Form Energy also provides a grid toolkit, FormwareTM, to provide grid planners with the capability to identify investments that will maintain long-term renewable grid energy reliability.

Partnering with leading academic institutions, the company has developed a highly capable, next-generation, and technology-neutral toolkit.

What Does This Mean For the Future of the Industry?

The energy industry is undergoing a revolution currently, with legacy fossil fuel power stations being phased out in favor of cheap, clean, and renewable energy. However, renewables are extremely vulnerable to daily and seasonal fluctuations in power generation capabilities.

For renewable energy to be viable, it must meet the power generation capabilities of current fossil fuel technologies.

It must also be cost-competitive with coal, natural gas, and oil. A key roadblock is long-term and reliable energy storage, which cannot be adequately satisfied by current battery technology.

Form Energy’s next-generation iron-air battery technology could help to revolutionize energy storage for the global electric system. The company predicts tens of gigawatts of demand will be unlocked for multi-day storage over the next decade. This will help the US achieve its net zero commitments.

With this technology, Form Energy could help the US economy (and possibly the world economy) accelerate toward a resilient, reliable full decarbonized energy grid. With full deployment, billions of dollars in savings could be realized for American energy consumers.

References and Further Reading

Form Energy (website) Available at: https://formenergy.com/

Orf, D (2023) Iron-Air Batteries Are Here. They May Alter the Future of Energy [online] popularmechanics.com. Available at: https://www.popularmechanics.com/science/energy/a42532492/iron-air-battery-energy-storage/

Bonheur, K (2019) Lithium-ion Battery: Advantages and Disadvantages [online] profolus.com. Available at: https://www.profolus.com/topics/lithium-ion-battery-advantages-and-disadvantages

Wagner, O.C (1968) Secondary Iron-air Batteries [online] Nasa.gov. Available at: https://ntrs.nasa.gov/citations/19690000955

Disclaimer: The views expressed here are those of the author expressed in their private capacity and do not necessarily represent the views of AZoM.com Limited T/A AZoNetwork the owner and operator of this website. This disclaimer forms part of the Terms and conditions of use of this website.

Reginald Davey

Written by

Reginald Davey

Reg Davey is a freelance copywriter and editor based in Nottingham in the United Kingdom. Writing for AZoNetwork represents the coming together of various interests and fields he has been interested and involved in over the years, including Microbiology, Biomedical Sciences, and Environmental Science.


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