Spatially Decoupled Bulk‐Surface Engineering of Single‐Crystal Li‐Rich Cathodes via a Rigidified Framework and Frictionless Li‐Ion Pathway

ABSTRACT Lithium‐rich manganese‐based oxides (LRMOs) are attractive next‐generation cathodes for lithium‐ion batteries (LIBs), owing to their ultrahigh capacity and high operating potential. Although single‐crystal LRMOs (SC‐LRMOs) mitigate intergranular fractures associated with polycrystalline particles, they still suffer from sluggish Li + transport and intragranular fatigue driven by uncontrolled oxygen release. Herein, a spatially decoupled “rigidified framework–frictionless pathway” strategy integrating bulk Zr 4+ doping with oleic acid (OA)‐induced surface reconstruction is proposed. Comprehensive characterizations and density functional theory (DFT) calculations reveal that Zr 4+ substitution rigidifies the bulk lattice by reducing the antibonding orbital occupancy of neighboring Mn─O bonds, suppressing oxygen loss and intragranular microcracking. In contrast, surface‐localized OA‐induced thermal reduction generates oxygen vacancies (O v ) and triggers a layered‐to‐spinel reconstruction near the surface, thereby enabling rapid Li + transport. Within the modified framework, the introduced O v upshifts the O 2p band center and enhances local anionic polarizability, effectively screening Li─O electrostatic repulsion and lowering the Li + migration barrier from 0.548 to 0.405 eV. Hence, the optimized Zr‐SC@OA cathode exhibits an initial Coulombic efficiency (ICE) of 86.6% and a reversible capacity of 298.8 mAh g −1 . This bulk‐surface decoupling design offers a rational strategy to reconcile thermodynamic stability with transport kinetics in high‐energy anionic‐redox cathodes.