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High‐capacity Ni‐rich layered oxides are considered as promising cathodes for lithium‐ion batteries. However, the practical applications of LiNi0.83Co0.07Mn0.1O2 (NCM83) cathode are challenged by continuous transition metal (TM) dissolution, microcracks and mixed arrangement of nickel and lithium sites, which are usually induced by deleterious cathode–electrolyte reactions. Herein, it is reported that those side reactions are limited by a reliable cathode electrolyte interface (CEI) layer formed by implanting a nonsacrificial nitrile additive. In this modified electrolyte, 1,3,6‐Hexanetricarbonitrile (HTCN) plays a nonsacrificial role in modifying the composition, thickness, and formation mechanism of the CEI layers toward improved cycling stability. It is revealed that HTCN and 1,2‐Bis(2‐cyanoethoxy)ethane (DENE) are inclined to coordinate with the TM. HTCN can stably anchor on the NCM83 surface as a reliable CEI framework, in contrast, the prior decomposition of DENE additives will damage the CEI layer. As a result, the NCM83/graphite full cells with the LiPF6‐EC/DEC‐HTCN (BE‐HTCN) electrolyte deliver a high capacity retention of 81.42% at 1 C after 300 cycles at a cutoff voltage of 4.5 V, whereas BE and BE‐DENE electrolytes only deliver 64.01% and 60.05%. This nonsacrificial nitrile additive manipulation provides valuable guidance for developing aggressive high‐capacity Ni‐rich cathodes.

Ni-rich layered oxides are the most promising cathode materials for Li-ion batteries due to their high specific capacity and reasonable cost. Unfortunately, undesired residual Li compounds (RLCs) tend to form on the surface of Ni-rich materials, causing severe limitations to their commercialization. In this work, water washing and subsequent recalcination strategies were adopted to eliminate surface RLCs as well as guarantee the cycling stability of LiNi 0.83 Co 0.11 Mn 0.06 O 2 materials. The washing/recalcination processes not only induced the migration of Li + and the redox of Ni 2+ /Ni 3+ but also contributed to the variation of the specific surface area. Combined with the electrochemical properties, we found that these structure evolutions showed different impacts on the performance as the recalcination temperatures changed. Taking capacity and cycling stability into account, the optimal recalcination condition was selected. More importantly, the relationships between washing/recalcination processes and structure performance were established. This work reinforces the understanding of modified Ni-rich materials and motivates the development of advanced cathodes for batteries.

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