How do iron-air batteries work?
Unlike lithium-ion, iron-air batteries don’t require any expensive materials. The principal behind it is called “reversible rusting.”
Iron-air batteries are comprised of iron-air cells, which are surrounded by an electrolyte. Using reverse-rusting, the cells take in air transforming the iron into iron oxide (rust) and produce energy. To charge the battery back up, a current reverses the oxidation turning the cell back to iron.
NASA first experimented with the technique in the late 1960s. Obviously it went nowhere.
Why?
Iron-air batteries are big. Each Form Energy iron-air battery is about the size of a washer/dryer set. But that isn’t the major drawback. The biggest obstacle is that they are slow to recharge.
Well see if Form Energy is the company that can overcome the downsides of iron-air technology and produce a commercially viable product.