The American company Form Energy plans to build the world's largest battery with a capacity of 8,500 MWh. The project involves converting a former pulp and paper mill in Lincoln, Maine, into a large-scale energy storage facility capable of supplying up to 85 MW to the grid, reports Interesting Engineering.
Instead of the traditional lithium-ion batteries used for energy storage, Form Energy uses iron-air battery technology. This technology is ten times cheaper to implement, has a longer service life and carries fewer risks, especially in extreme temperatures.
The engineers explained: iron-air batteries work on the principle reversible process of rusting, using non-flammable water-based electrolyte. During discharge, the battery absorbs oxygen from the air, turning metallic iron into iron oxide or rust. During charging, this process is reversed, and the iron oxide is converted back into iron, releasing oxygen.
Each module of an iron-air battery, the size of a typical washing machine, contains about 50 cells, immersed in electrolyte. These modules are then grouped into megawatt units protected from adverse weather conditions. The Form Energy battery will store energy from wind and solar power plants and help meet the needs of the grid at times when energy production becomes critically low.
The project is funded by the US Department of Energy, which allocated $147 million for its implementation. . The world's largest battery is expected to be operational by 2028.