MIT’s liquid battery is actually composed of two molten metals, acting as electrodes, and one molten salt, acting as an electrolyte.
As always, MIT is coming with lots of interesting ideas that often represent really viable ways of improving our energy sources. This time, MIT has come up with a special type of battery never seen before.
It is a liquid battery, since everything in it is liquid. The liquids are, from bottom to top: antimony, sodium sulfide, and magnesium.
When the liquid battery is fully charged, the two metals are separated from the electrolyte. When you connect a load on the battery, the metals slowly react and dissolve into the electrolyte, ionize, and the electrolyte portion is getting larger, as the electrodes get thinner. When you charge the battery, magnesium ions are reduced and the antimony ions are oxidized, and return to their initial state. The process resembles the picture above.
The scientists have found cheaper and better materials for real world applications, but they are not disclosing them already. One of the liquid battery inventors, Donald Sadoway, envisions this battery powering up the entire New York city at night, while during the day they are being charged from the greatest solar power farm in the world producing 13,000 megawatts. The calculations revel they’d need about 60,000 square meters of battery storage.
Except the fact that these batteries can bear very high currents, “tens of times higher than any [battery] that’s ever been measured”, no other numbers are given (like recharging time, self-discharge, capacity).
Anyway, expect this liquid battery to be used commercially only in the next five years. It’s a more environmentally friendly option for our future electric cars. Let’s hope it’s not too late until decent storage options are actually used, from the moment of their invention.