High Performance 4.6 V LiCoO <sub>2</sub> Cathode Materials Enabled by Surface Lattice Modulation
Abstract
ABSTRACT Charging the cathode of LiCoO 2 (LCO) to higher voltages, typically 4.6 V, is able to increase reversible capacity, but meanwhile raises serious stability issues. Here, through a decomposition‐induced reconstruction (DIR) process, we demonstrate the possibility of modulating the surface lattice of LCO with high precision in depth control, thereby enabling the 4.6 V LCO cathode to have both high capacity and structural integrity. Following the precise construction of a conformal Y(OH)CO 3 nanoshell, a sintering process induces the hydrocarbonate decomposition, which releases CO 2 to transform the layered structure of the LCO crust into rock‐salt‐like lattices, forming a renovated surface with high electrochemical and mechanical stability. The prepared LCO cathode delivers a high reversible capacity of 215.8 mAh g −1 at 0.1 C with an extraordinary capacity retention of 93.0% after 100 cycles at 4.6 V. The much‐improved stability is meanwhile manifested by cyclability test at 1 C (85.5% vs 13.6% of pristine LCO after 500 cycles), as well as tests at harsh conditions. Our results highlight the essential role played by the surface chemistry in addressing the stability issue of high voltage LCO cathode, and provide useful guidelines for the development of lithium‐ion batteries with higher energy density.
Article Details
Authors (11)
Qi‐Wen Liu
CAS Key Laboratory of Molecular Nanostructure and Nanotechnology and Beijing National Laboratory for Molecular Sciences Institute of Chemistry Chinese Academy of Sciences (CAS) Beijing P. R. China
Si‐Jie Guo
CAS Key Laboratory of Molecular Nanostructure and Nanotechnology, and Beijing National Laboratory for Molecular Sciences, Institute of Chemistry Chinese Academy of Sciences (CAS) Beijing 100190 P.R. China
Xin‐Cheng Lei
Beijing National Laboratory for Condensed Matter Physics Institute of Physics, Chinese Academy of Sciences (IPCAS) Beijing P. R. China
Hao Huang
Si‐Qi Lu
CAS Key Laboratory of Molecular Nanostructure and Nanotechnology and Beijing National Laboratory for Molecular Sciences Institute of Chemistry Chinese Academy of Sciences (CAS) Beijing P. R. China
Si‐Dong Zhang
CAS Key Laboratory of Molecular Nanostructure and Nanotechnology and Beijing National Laboratory for Molecular Sciences Institute of Chemistry Chinese Academy of Sciences (CAS) Beijing 100190 China
Ting‐Ting Wu
CAS Key Laboratory of Molecular Nanostructure and Nanotechnology, and Beijing National Laboratory for Molecular Sciences, Institute of Chemistry Chinese Academy of Sciences (CAS) Beijing 100190 P.R. China
Wen‐Bo Ma
CAS Key Laboratory of Molecular Nanostructure and Nanotechnology and Beijing National Laboratory for Molecular Sciences Institute of Chemistry Chinese Academy of Sciences (CAS) Beijing P. R. China
Wei‐Dong Zhou
Beijing Advanced Innovation Center for Soft Matter Science and Engineering State Key Laboratory of Organic‐Inorganic Composites Beijing University of Chemical Technology Beijing P. R. China
Dong Su
Beijing National Laboratory for Condensed Matter Physics, Institute of Physics
An‐Min Cao
CAS Key Laboratory of Molecular Nanostructure and Nanotechnology Beijing National Laboratory For Molecular Sciences Institute of Chemistry Chinese Academy of Sciences Beijing China