Abstract: The electronic structures of bare and ZrO2-coated Li(Ni0.8Co0.15Al0.05)O2 electrode systems were investigated using a combination of time-resolved X-ray diffraction and soft X-ray absorption spectroscopy (XAS) techniques. The ZrO2 coating on the surface of Li(Ni0.8Co0.15Al0.05)O2 was effective in elevating the onset temperature of the dissociation of charged Li0.33(Ni0.8Co0.15Al0.05)O2, which will enhance the safety of Li-ion cells. Soft XAS spectra of the Ni LII,III-edge in the partial electron yield mode were obtained, which showed that the enhanced electrochemical properties and thermal stability of the cathode materials by ZrO2 coating can be attributed to the suppression of unwanted Ni oxidation state changes at the surface. Graphical Abstract: The electronic structural effects of a ZrO2 coating on Li(Ni0.8Co0.15Al0.05)O2 were examined by soft X-ray absorption spectroscopy. The coating stabilized the Ni oxidation state at the electrode surface against decomposition [Figure not available: see fulltext.]
Bibliographical noteFunding Information:
This work was supported by the R&D Convergence Program of NST (National Research Council of Science & Technology) of Republic of Korea and the Energy Efficiency & Resources of the Korea Institute of Energy Technology Evaluation and Planning (Project No. 20142020103090) grant funded by the Korea government Ministry of Trade, Industry & Energy. This work was also supported by the Dongguk University Research Fund of 2014. The work done at Brookhaven National Lab. was supported by the U.S. Department of Energy, the Assistant Secretary for Energy Efficiency and Renewable Energy, Office of Vehicle Technologies, under Contract No. DE-SC0012704.
© 2017, Springer Science+Business Media Dordrecht.
All Science Journal Classification (ASJC) codes
- Chemical Engineering(all)
- Materials Chemistry