Accelerated Oxygen Redox Kinetics via Synergistic Electron Modulation at Asymmetric Dual 180° Oxygen Bonds in Co-Free Li-Rich Cathodes

While oxygen redox in Li-rich cathodes enables exceptionally high capacities, its sluggish kinetics often lead to poor rate capability and severe voltage decay. Here, we construct asymmetric, near-180° Li–O–Al and Li–O–Na configurations that target the oxygen states in a Co-free, Mn-rich cathode. We demonstrate that Li–O–Al configuration lowers the energy barrier for oxygen electron excitation through strong Al–O covalency, whereas the Li–O–Na structure enhances the electron-loss capability of active oxygen. The interplay between these two configurations improves the kinetics of the oxygen redox reaction. This modulation effectively accelerates both electronic and ionic transport in lithium-rich materials during high-voltage cycling. The Al/Na codoped cathode delivers 314.8 mAh g–1 at 0.1 C and 151.2 mAh g–1 at 5 C, compared with 222.6 and 85.8 mAh g–1 for the undoped cathode. This dual-configuration strategy enables high-capacity and accelerated oxygen redox in Mn-rich, Co-free, and Li-rich cathodes.