A startup named Form Energy is working to switch completely from fossil fuels for power generation. For the same purpose, the firm thinks that Iron is the key to building better batteries, as it is cheap as well as abundant. The company’s “iron-air” batteries cost less than a tenth of lithium-ion batteries and can store energy for days.
One of the biggest challenges related to the usage of renewable energy involves the fact that when the Sun is not shining and the wind is not blowing, the grid still needs a source of power. Lithium-ion batteries like the giant batteries that Tesla has installed in Australia are capable of storing the energy generated by renewables. But they are quite expensive for long-term storage.
“It became very clear that although lithium-ion was cheap, and continues to get cheaper—and will be deployed at large scales on the grid—it was still too expensive to go after the biggest opportunity and the biggest opportunity on the grid, which was being able to be cheap enough so you can fully replace coal plants, natural gas plants, with renewable,” says Form Energy CEO Mateo Jaramillo, who launched the startup in 2017 after leaving Tesla.
According to Jaramillo, dealing with intermittent renewable energy for a few hours, or overnight is not as hard. But backing up that power for a longer period of time is much more difficult. After leaving Tesla, he did not know how to resolve the issue.
Thus the team worked on multiple possibilities for the technology.“The problem that we were going after is a very large problem, and it’s a very large market,” he says. “So any option we were considering had to be able to scale to meet the size of the challenge—thousands of terawatt-hours capability. And it also had to be safe. It had to be fundamentally cheap, fundamentally scalable, and fundamentally safe.”
Finally, they reached the conclusion that the iron-air batteries would be suitable and had proven to work in earlier tests. Each of the batteries at the company pulls in oxygen and converts iron inside to rust, and then charges by using the electricity to “unrust”. This conversion of iron to rust again generates a current. Jaramillo says, “By providing electricity to that anode, we’re essentially driving off that rust and returning the iron back to its metallic state.”
Moreover, iron is one of the most abundant elements on Earth. Companies like Tesla are working on the means to incorporate iron into their lithium batteries to replace other rare minerals, including cobalt. Iron-air batteries work well for providing energy over days to the electric grid, and as they discharge power slowly, so may not be a good fit for an electric car. power