Surface-to-bulk engineering with high-valence W^(6+) enabling stabilized single-crystal LiNi_(0.9)Co_(0.05)Mn_(0.05)O_(2) cathode  

作　　者：Jun-Ke Liu Xue-Rui Yang Chuan-Wei Wang Zu-Wei Yin Yi-Yang Hu Li Deng Zhen Wang Yao Zhou Jun-Tao Li 

机构地区：[1]College of Energy,Xiamen University,Xiamen 361005,Fujian,China [2]College of Chemistry and Chemical Engineering,Xiamen University,Xiamen 361005,Fujian,China [3]School of Physics and Materials Science,Nanchang University,Nanchang 330031,Jiangxi,China

出　　处：《Journal of Energy Chemistry》2024年第11期67-76,共10页能源化学（英文版）

基　　金：National Key Research and Development Program of China (2022YFB2502103);National Natural Science Foundation of China (22279107, 22309153);Fundamental Research Funds for the Central Universities (20720230039)。

摘　　要：Single-crystal Nickel-rich layered oxides has been recognized as one of the promising cathodes for nextgeneration lithium batteries on account of their high capacity,while its practical application was hindered by structural instability and slow Li^(+) transfer kinetics.Herein,a surface-to-bulk engineered single-crystal LiNi_(0.9)Co_(0.05)Mn_(0.05)O_(2)(Ni90) cathode,which features W-doped bulk and Li_(2)WO_(4) surface layer,was successfully achieved by a one-step high-valence W^(6+) modification.The as-obtained W-modified Ni90 delivers excellent cycling stability(89.8% capacity retention after 300 cycles at 0.5 C)and rate capability.The enhanced electrochemical performance was ascribed to the doped-W induced stabilized lattice oxygen,reduced Li^(+)/Ni^(2+) mixing and inhibited H2-H3 phase transition in the bulk,and Li_(2)WO_(4) layer generated stabilized cathode/electrolyte interface.In addition,the thinner LiF-rich cathode electrolyte interphase(CEI) on surface and smaller grain size for W-modified Ni90 benefit to its Li^(+) diffusion dynamics.The effect of high-valence W^(6+)on single-crystal Ni-rich cathode was firstly revealed in detail,which deepens the understanding of electrochemical behavior of Ni-rich cathode with high-valence cations modification,and provides clues for design of high-performance layered cathodes.

关 键 词：Single-crystal Ni-rich cathode Surface-to-bulk engineering High-valence cations Structural stability Interfacial side reaction 

分 类 号：TM912[电气工程—电力电子与电力传动]