Achieving High Reversible Anionic Redox Activity of Li‐Rich Layered Oxides via Mg and Mo Co‐Doping

Abstract Li‐rich layered oxides (LLO) exhibit a distinctive anionic redox capability, enabling them to deliver exceptionally high specific capacity. However, the irreversibility of anionic redox in LLO gives rise to significant issues, including oxygen release and structure phase transitions. These challenges adversely affect performance, resulting in capacity and voltage degradation, thereby hindering the commercialization of LLO. Here, density functional theory (DFT) is employed to explore the electronic structure of LLO, and reveal that the incorporation of Mg and Mo elements into LLO enhances the overlap between the O 2p nonbonding orbital and the (TM─O) ^* antibonding orbital, thereby boosting anionic redox reversibility. Experimental results corroborate the theoretical predictions, demonstrating that the initial Coulombic efficiency rises from 80.8% to 90.1%, while capacity retention increases from 70.8% to 95.3% after 300 cycles at 1 C. Additionally, the full cell delivers a reversible capacity of 262.6 mAh g ⁻¹ at 0.1 C. This work presents a novel method for modifying the electronic structure of LLO through Mg and Mo co‐doping, offering new insights for the development of high‐performance lithium‐ion batteries.