Another view of oxygen in cathodes for high energy batteries

The concept of utilizing anionic redox reactions to achieve high energy batteries has been revived for almost a decade by now; however, both its fundamental mechanism and practical implementation remain elusive and highly debated. In this issue of Joule, Weixin Song, Peter D. Nellist, and co-workers utilized electron ptychography to image the oxygen sublattice distortion of a Li-rich material that is known to involve oxygen redox reactions. Through the dose-efficient ptychography reconstruction with picometer resolution, they provide a beautiful demonstration of detecting the atomic placements of both the heavy, i.e., transition metals, and light, i.e., O and Li, elements of the Li-rich electrode at different electrochemical states, inspiring valuable discussions on the oxygen activities in battery cathodes.