Real-time lithium-oxigen reaction process visualized for the first time

Researchers from the RIKEN Byon Initiative Research Unit have succeeded in visualizing the lithium-oxygen (Li−O₂) electrochemical reaction that takes place in nonaqueous Li-O₂ batteries, for the first time. 

The researchers used a technique called operando atomic force microscopy (AFM), coupled with electrochemical equipment to observe the reaction process at the nano/micrometer scale. They used a highly oriented pyrolytic graphite (HOPG) electrode, an O₂ gas-saturated lithium ion–containing tetraglyme, representative of the carbon cathode, and an ether–based electrolyte extensively used in Li–O₂ batteries.

They observe the nucleation, growth, and decomposition of Li₂O₂ nanoplates, product of the Li-O₂ reaction, formed following the oxygen reduction reaction.

Their observations provide the first visualization of the Li−O₂ reaction process and reveal useful information about the reaction and its products, and will help scientists understand the reaction and design the optimum conditions for Li–O₂ batteries.

The work is published in the Journal of the American Chemical Society DOI: 10.1021/ja405188g