Tailoring Stabilized Multilevel Dynamic Structure Evolution Enables 4.6 V High‐Voltage Single‐Crystal Ni‐Rich Cathode

Abstract Ni‐rich layered oxides (Li[Ni x Co y Mn 1‐ x ‐ y ]O 2 (NCM, x ≥0.8)) are promising cathodes for high‐energy lithium‐ion batteries but suffer from the inherent chemomechanical, structural, and interfacial instability, leading to severe dynamic structural degradation, especially under high‐voltage operation. Herein, a self‐engineered lattice modification has been developed for a single‐crystal Ni‐rich cathode by simultaneously incorporating Zr and Al via a facile thermal treatment. The mechanism of high‐voltage stable performance and the optimized multilevel dynamic structure evolution in cation diffusion, microstructure, and interfaces are systematically unraveled by in situ measurement and theory calculation/simulation. The Al/Zr co‐doping effectively suppresses the harmful phase transition and mitigates anisotropic lattice distortions, thus alleviating the formation of intragranular cracking and particle gliding. Moreover, it also reduces the Li/Ni cation mixing, facilitates stable Li + ‐diffusion, and prevents inhomogeneous Li + ‐distribution, effectively suppressing internal stress. Additionally, the irreversible bulk lattice rearrangement and interfacial parasitic reaction are efficiently mitigated, facilitating the stable interface. As anticipated, it demonstrates a notably improved capacity retention rate of 96.8% after 100 cycles at 1C at 3.0–4.5 V, significantly surpassing the pristine cathode (76.0%). Even at a high cutoff voltage of 4.6 V, it retains 87.8% capacity, realizing a high energy density of 774.1 Wh kg −1 cathode. This research offers valuable insights into stabilizing the bulk lattice and surface chemistry of single‐crystal Ni‐rich cathodes, paving the way for the large‐scale development of advanced durable LIBs.