Via
NewAtlas.com:
MIT's 'crazy' fuel cell could power electric planes (Sodium-Air Fuel-Cell Aircraft) by Ben Coxworth
Scientists have developed a fuel cell system which they say could ultimately have enough energy capacity to power regional electric aircraft. They state that the technology is capable of carrying over three times as much energy per unit of weight as a lithium-ion battery.
Picture: A proof-of-concept "H-cell" with a liquid sodium metal chamber on the left, an air chamber on the right, and a solid ceramic electrolyte (black) in the middle (Gretchen Ertl)
Created by Prof. Yet-Ming Chiang and colleagues at MIT, the current prototype device consists of two chambers linked by a solid ceramic electrolyte material. The fuel, namely liquid sodium metal, is in one of the chambers, while the other is filled with humid air.
Putting it simply, sodium ions pass from the one chamber, through the electrolyte, into the other chamber. Upon contact with the air, they chemically react with the oxygen in the gas, producing electricity. A porous electrode on the air-chamber-side of the electrode assists in this reaction.
The process does create sodium oxide as a byproduct, which the researchers state would soak up excess carbon dioxide from the atmosphere when expelled from aircraft in the exhaust.
Through a cascading series of reactions, the sodium oxide would ultimately form into sodium bicarbonate, aka baking soda. Chiang's team says that if the non-toxic compound were to end up falling into the ocean, it would de-acidify the water, actually helping to reverse one of the damaging effects of greenhouse gases...
