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Ni‐rich cathode material possesses a considerable theoretical capacity, yet achieving their full capacity potential remains challenging. Elevating its operation voltage is an effective approach, while the stability of Ni‐rich cathode material is relatively poor, which is limited by Li+/Ni2+ mixing. Herein, a strategy of cation/anion co‐doping is proposed for single‐crystal ultrahigh‐nickel cathode LiNi0.92Co0.04Mn0.04O2 operated at 4.5 V. The enhancement mechanism is explicitly revealed by in situ/ex situ tests and theory calculations. Specifically, Mo6+ and F− are introduced to construct an appropriate Li+/Ni2+ antisite defects structure at the particle surface, which can maintain the low‐defect Li+ layered channel inside the bulk simultaneously, inducing a stable access portal for Li+ transport from the cathode/electrolyte interface. More importantly, the Li+/Ni2+ antisite passivation layer on the surface can uphold the stability of Li‐layer and optimize the reactive behavior of Ni2+, thus boosting the interfacial stability and reducing the lattice mismatch. As a result, it can achieve high capacity (204 mAh g−1 at 1 C) and stable retention during long‐term high‐voltage measurements both in half‐cell (87.1% after 200 cycles) and full‐cell (91.9% after 400 cycles). This facile strategy provides a feasible technical reference for further exploiting the ultrahigh‐capacity of Ni‐rich cathode for commercial application. [ABSTRACT FROM AUTHOR]

We report the improved kinetic mechanism of a nickel-rich LiNi0.84Mn0.10Co0.03Al0.03O2 cathode. The important role of Co/Al in inhibiting cation disorder to increase the lithium ion diffusion rate is revealed. Impressively, it retains an excellent capacity retention of 76.8% after 200 cycles under the high-rate condition (5C). [ABSTRACT FROM AUTHOR]

It is crucial to minimize cobalt content in Ni‐rich layered single‐crystal cathodes due to their high price and limited availability, yet it will inevitably lead to cation disordering, capacity degradation, and thermal issues. Herein, to overcome the intrinsic trade‐off between performance and composition of Ni‐rich Co‐less single‐crystal cathodes, a precursor engineering strategy with an epitaxially grown cobalt enrichment on the surface is innovatively proposed. In contrast to traditional coating modifications with random orientation and rigid surface‐bulk boundary, the epitaxially enriched surface cobalt layer on the precursor undergoes rapid interdiffusion with the internal Ni3+ during the optimized sintering process. This interdiffusion eliminates the surface‐bulk boundary, promoting the uniform distribution of cobalt and synergistically addressing the Li/Ni intermixing. Moreover, an enhanced surface Li+ diffusion is obtained, thereby suppressing the Li+ concentration gradient and intragranular cracks generation. Consequently, the modified LiNi0.7Co0.07Mn0.23O2 exhibits impressive cycling stability with increased capacity retention in both coin‐type half‐cells and pouch‐type full‐cells (91% after 1000 cycles), even under the harsh condition of high‐temperature, surpassing the majority of previously reported Ni‐rich cathodes. This work opens new avenues toward the low cost, high energy density, thermal stability, and long cyclic life for Ni‐rich Co‐less cathodes and sheds light on large‐scale commercial production. [ABSTRACT FROM AUTHOR]