Iron and air batteries began to be talked about a long time ago, and there is already a company called Form Energy https://formenergy.com/ which will build its first facility in West Virginia.
The idea is not new, since around the year 1960 NASA investigated the subject without reaching any concrete result. But the pressure to find viable alternatives to energy storage has reopened the issue, and technological developments today allow us to obtain these types of batteries at competitive prices.
Current batteries are dominated by lithium, but they have a few drawbacks like their high cost, their environmental effects to obtain lithium, when it is time to discharge it does not last long (less than 10 hours), and the scarcity of many products used in its manufacture.
Iron is the fourth most abundant product in nature, so iron-air batteries can be built with abundant and cheap materials and without affecting the environment. They have the advantage that their discharge lasts much longer than lithium ones, up to 100 hours, and they have the disadvantage that they take much longer to charge than lithium ones and are larger, so they cannot be used in vehicles, and electronic equipment.
The process is fairly simple. It is based on oxidizing and deoxidizing iron using a principle called “reverse rusting”.
When discharged, the battery breathes oxygen from the air and turns iron metal into rust, producing electricity.
When charged, a current is passed through it and iron oxide is converted to iron, and oxygen is expelled from the battery
With this type of batteries in operation, temporary drops in the supply of renewable energies (solar and wind) can be avoided much better, and not have to depend so much on fossil fuel energy.
Our entire energy generation and supply system must be renewed if we really want to have sustainable energy. And as we are fighting against time, all viable alternatives are positive and should be considered and promoted by our administrations.
We are very, very far from becoming sustainable in 2050 according to the Goals of the Paris Agreement. Many are already beginning to throw out the towel to achieve those objectives and I think it is a mistake, despite how difficult it is.
If we really wanted to achieve it, we could do it, because there are technical and economic means to do it. We just have to develop them with due priority and the necessary economic contribution.
But I have very serious doubts that we will do it, because there are many opposing interests of very, very powerful people. We are that selfish and short-sighted.
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