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Prevailing Li‐rich layered oxide cathodes (LLOs) possessing with polycrystalline morphology suffer from unsatisfactory cyclic stability due to serious structural failures including irreversible oxygen release, phase transformation, and microcrack, further limiting its commercial application for high‐energy‐density lithium‐ion batteries. Herein, single‐crystallization combining with a simple boric acid treatment strategy is applied to robust the stability of lattice structure for achieving the reversible oxygen anionic redox of LLOs. The obtained single‐crystal LLOs display less grain boundaries and excellent mechanical stability, contributing to suppress the accumulation of lattice strain and microcracks. Additionally, the induced surface Li2B4O7 with spinel phase coating and bulk gradient B doping after boric acid treatment significantly inhibit the irreversible oxygen release and enhance the stability of lattice structure. Besides, lattice structure regulation also boosts the Li+ diffusion kinetics due to the existence of oxygen defects, fast Li‐ion conductive coating, and enlarged Li+ layer spacing. As a result, the modified SC‐LLOs showcase superior cyclic stability with a capacity retention of 87.42% after 300 cycles at 1 C and excellent rate performance with a high capacity of 144.9 mAh g−1 at 5 C. This work provides some significant references to strengthen the structural stability of single‐crystal LLOs with long‐term cyclic capability via lattice engineering. [ABSTRACT FROM AUTHOR]

Anionic and cationic redox chemistries boost ultrahigh specific capacities of Li‐rich Mn‐based oxides cathodes (LRMO). However, irreversible oxygen evolution and sluggish kinetics result in continuous capacity decay and poor rate performance, restricting the commercial fast‐charging cathodes application for lithium ion batteries. Herein, the local electronic structure of LRMO is appropriately modulated to alleviate oxygen release, enhance anionic redox reversibility, and facilitate Li+ diffusion via facile surface defect engineering. Concretely, oxygen vacancies integrated on the surface of LRMO reduce the density of states of O 2p band and trigger much delocalized electrons to distribute around the transition metal, resulting in less oxygen release, enhancing reversible anionic redox and the MnO6 octahedral distortion. Besides, partially reduced Mn and lattice vacancies synchronously stimulate the electrochemical activity and boost the electronic conductivity, Li+ diffusion rate, and fast charge transfer. Therefore, the modified LRMO exhibits enhanced cyclic stability and fast‐charging capability: a high discharging capacity of 212.6 mAh·g−1 with 86.98% capacity retention after 100 cycles at 1 C is obtained and to charge to its 80%, SOC is shortened to 9.4 min at 5 C charging rate. This work will draw attention to boosting the fast‐charging capability of LRMO via the local electronic structure modulation. [ABSTRACT FROM AUTHOR]