Delocalized electron holes on oxygen in a battery cathode

Oxide ions in transition metal oxide cathodes can store charge at high voltage offering a route towards higher energy density batteries. However, upon charging these cathodes, the oxidized condense to form molecular O2 trapped material. Consequently, discharge is much lower than charge, leading undesirable hysteresis. Here we capture nature of electron holes on O2? before formation by exploiting suppressed rearrangement ribbon-ordered Na0.6[Li0.2Mn0.8]O2. We show that formed are delocalized across coordinated two Mn (O–Mn2) arranged ribbons layers. Furthermore, track hole states as they gradually localize structure over period days. Establishing important if truly reversible high-voltage O-redox be realized. The mechanism oxygen redox high-energy elusive. authors illustrate electron-hole ions, insights for realizing reversible, cathodes.