Researchers are working on a lithium–oxygen battery
Researchers at the University of Illinois at Chicago and at Argonne National Laboratory have been working on a new lithium-oxygen battery that works in a natural-air environment and that can still function after an astonishing 750 charge/discharge cycles.
These findings have been reported in the journal Nature.
Researchers estimate that Lithium-air batteries are capable of holding up to five times more energy than the lithium-ion batteries.
The development of this technology has been going on for years now but, until recently, but many obstacles have stood in the way of this research.
Larry Curtiss, Argonne Distinguished Fellow and co-principal investigator explained how the magazine Nature was very interested in their article as “others have tried to build lithium-air battery cells that run on air, but they failed because of little cycle life.”
Content of the article
How a lithium-oxygen battery works
A normal battery supplies electrons by undergoing reversible chemical reactions. Until now, all the reactants to the process had to be inside the battery, a design that obviously added volume and weight to the battery itself.
Lithium-air batteries could, in theory, completely change this approach.
They are designed to have as one as one electrode a lithium metal rather than a lithium-containing chemical. On the other electrode, the lithium reacts with oxygen in the air. When the battery is charged again, the reaction reverses, and the oxygen returns to our atmosphere.
This technology allows fewer chemicals inside the battery, making possible to achieve a much higher energy density.
Some tests have show how lithium-air batteries with an energy density five times that of current lithium-ion tech.
Two key discoveries
The first key discovery of the team’s battery cell in an innovative protective coating for the lithium metal anode, which prevents the anode from reacting with oxygen reducing deterioration.
The second one is new electrolyte mixture that allows the cell to function in an air atmosphere.
As already mentioned, during tests under an air environment, this cell maintained high performance for more than 700 cycles, far surpassing any previous similar technology.
“Our lithium-air battery design represents a revolution in the battery community,” said Amin Salehi-Khojin, co-corresponding author of the paper and assistant professor of mechanical and industrial engineering. “This first demonstration of a true lithium-air battery is an important step toward what we call ‘beyond lithium-ion’ batteries, but we have more work to do in order to commercialize it.”
Uses of lithium-oxygen batteries
Lithium-air cells are indeed very interesting for the automotive industry. Their high theoretical specific and volumetric energy density could be much higher compared to petrol.
Electric motors can already provide high efficiency (95% compared to 35% for a conventional petrol engine) but, lithium-air cells while offering a range equivalent to today’s vehicles, could be designed with a battery pack ⅓ the size of standard fuel tanks.
The high capacity and their potential long-lasting lifespan of Lithium-air battery could also be used very successfully in microgrid and other energy storage systems helping to resolve the issue of renewable energies intermittency.