Regulating Li Extraction in Transition Metal Layer for High‐Performance Li‐Excess Layered Oxide Cathode with Intergrowth Structure
Abstract
ABSTRACT In lithium‐excess layered oxide cathodes, the extra lithium within transition metal (TM) layers (i.e., Li [TM] ) can trigger anionic redox to provide additional capacity. However, substantial extraction of Li [TM] may induce irreversible/detrimental local structural rearrangements. The conventional edge‐shared connecting configuration between LiO 6 and TMO 6 octahedra facilitates interlayer migration of Li [TM] . In contrast, the face‐shared configuration has the potential to limit the mobility of Li [TM] , but this metastable configuration cannot be harvested via traditional calcination. Herein, during Na‐to‐Li ion exchange in P2 phase Na 0.66 [Li 0.22 TM 0.78 ]O 2 precursor, we observe that the random gliding of TMO 2 layers yielding Li 0.66 [Li 0.22 TM 0.78 ]O 2 with O2/O6 intergrowth structure. Despite the random gliding, the functional face‐shared configuration is successfully obtained and proven to effectively restrict interlayer migration of Li [TM] during charging. Consequently, we observe the suppressed formation of aggregated vacancies and O–O dimers within the TM layers. Ultimately, our synthesized O2/O6 Li‐excess demonstrates enhanced structural reversibility and improved capacity/voltage retention. This oxygen‐stacking engineering provides a compelling strategy for developing cathodes with enhanced local structural reversibility.
Article Details
Authors (21)
Yawen Yan
State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering Xiamen University Xiamen P. R. China
Guifan Zeng
Discipline of Intelligent Instrument and Equipment the State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical Engineering Xiamen University Xiamen P. R. China
Chenglin Pua
School of Materials Science and Engineering Tsinghua University Beijing China
Shiyuan Zhou
Yonglin Tang
State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 P. R. China
Juping Xu
Institute of High Energy Physics
Wen Yin
Yongfu Qiu
School of Environment and Civil Engineering Research Institute of Interdisciplinary Science Dongguan University of Technology Dongguan Guangdong 523808 P.R. China
Linzhi Chen
Hong‐Gang Liao
State Key Laboratory of Physical Chemistry of Solid Surfaces Department of Chemistry College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 P.R. China
Songyan Bai
College of Chemistry Fuzhou University Fuzhou Fujian 350116 China
Qingsong Wang
Maolin Yang
Yinguo Xiao
Ting Lin
Beijing National Center for Electron Microscopy and Laboratory of Advanced Materials, School of Materials Science and Engineering
Zhen Chen
Qingyuan Li
Yang Sun
Lin Gu
Yu Qiao
Shi‐Gang Sun
State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical Engineering Xiamen University Xiamen P. R. China