Researchers at the Kaist Institute in South Korea have developed a new material that can capture oxygen from the atmosphere. This material can be used in conjunction with lithium air batteries, which are not powered by oxygen, but, until now, have not been able to absorb it directly from the air.
Battery that “breathes”
The new discovery could start mass production of batteries that “breathe”. This is because, since the battery draws oxygen from the air, while being charged, and loses oxygen by a similar process – only in reverse – while in use, the charging and discharging process is very similar to breathing in living beings.
Although the discovery is promising, there is a major challenge to be overcome. In theory, oxygen and lithium batteries have an energy density 10 times greater than lithium-ion batteries, but their usage cycles are so low that they become practically disposable.
Increasing the durability of use cyclNew battery
When the size of an electrocatalyst material is reduced to the atomic level, the increase in surface energy leads to an increase in activity, but it also significantly accelerates the material’s agglomeration, causing the battery to deteriorate.
Therefore, the researchers are testing a method to reduce the excess potential of the electrocatalysts in the electrodes.
It was there that the team, coordinated by Jeung Kang, found a metal-organic structure (MOF: metal-organic framework), which functions as a spongy material full of microscopic pores.
The pores of the material are so small that they allow chemical reactions to be controlled at the molecular level, with the catalysts remaining stable because the nanopores prevent them from clumping together.
As the excess potential of the cobalt catalyst was reduced by 63.9%, the battery usage cycle was increased by 10 times.
Finally, this technique can be used to diversify materials according to various combinations of binders and organics, expanding the development of catalysts and other research fields.