离域电子
阴极
材料科学
电子结构
晶体结构
结构稳定性
电子顺磁共振
电化学
格子(音乐)
离子
共振(粒子物理)
凝聚态物理
四方晶系
限制
过渡金属
金属
相变
失真(音乐)
相(物质)
雅恩-泰勒效应
化学物理
核磁共振
结晶学
作者
Yi Li,Qinwen Cui,Ke Li,X. Li,Liang Yin,Erhong Song,Youwei Wang,Xiaolin Zhao,Jianjun Liu
摘要
ABSTRACT High‐nickel layered oxides are considered key cathode materials for high‐energy‐density lithium‐ion batteries due to their high specific capacity. However, the spin state localization of Ni 3+ (t 2g 6 e g 1 ) leads to severe Jahn–Teller distortion and structural degradation, limiting their cycling stability. This study proposes a high‐entropy transition metal (TM) regulation strategy, which introduces multicomponent vacant orbital TM ions (Mn, Ti, Nb, Ta, W, and Mo) to construct a Ni‐OO‐TM electronic resonance network, promoting the delocalization of Ni 3+ e g electrons, thereby suppressing spin disorder and enhancing structural stability. On the basis of this, a high‐entropy high‐nickel cathode material (HE‐LNF, LiNi 0.8 Fe 0.14 Mn 0.01 Ti 0.01 Nb 0.01 Ta 0.01 W 0.01 Mo 0.01 O 2 ) was designed. Combining first‐principles calculations with experimental characterization, the weakening effect of electronic resonance on magnetic frustration was revealed: This effect increases the phase transition temperature to 294.23°C by reducing the amplitude of lattice vibrations, while electronic delocalization reduces local nuclear repulsion, maintaining excellent structural stability with minimal lattice strain evolution after cycling. Electrochemical testing shows that HE‐LNF maintains a capacity retention rate of 91% after 100 cycles at a 0.33‐C rate, significantly outperforming traditional high‐nickel materials. This study provides new insights into the design of high‐stability high‐nickel cathodes based on electronic structure regulation.
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