Аннотация
ABSTRACT Chemo‐mechanical degradation, typically manifested as microcrack formation and parasitic electrode–electrolyte interfacial reactions, remains a critical obstacle to the practical implementation of state‐of‐the‐art Ni‐rich layered oxide cathodes in lithium‐ion batteries (LIBs). Herein, we propose a gradient configurational entropy engineering strategy to enhance the chemo‐mechanical robustness of LiNi 0.8 Co 0.15 Al 0.05 O 2 ; the resulting gradient‐entropy‐engineered cathode (denoted as GE) features an entropic gradient layer approximately 40 nm thick, with the outermost region reaching a configurational entropy of 1.6 R (> 1.5 R ). Notably, the introduction of a high‐entropy gradient surface effectively modulated the potential of the H2‒H3 phase transition, reduced volume changes during this process, and minimized side reactions at the electrode‒electrolyte interface. Consequently, the GE cathode exhibited markedly improved cycling stability, with the capacity retention increasing from 46.5% for the bare cathode to 88.1% for the GE cathode after 100 cycles at 1 C. This study establishes a configurational‐entropy‐based surface engineering strategy for stabilizing Ni‐rich layered cathodes and provides new insights into the rational design of high‐energy‐density cathode materials with improved chemo‐mechanical durability.