Two-dimensional hetero-spectral Raman/XAS correlation analysis of Li[Ni<sub>0.45sub>Co<sub>0.18sub>Mn<sub>0.25sub>Al<sub>0.12sub>]O<sub>2sub> cathode in the overcharged state
- 作者：Yeonju Park<sup>asup> ; Nam Hoon Kim<sup>asup> ; Hyun Chul Choi<sup>bsup><sup> ; sup><sup>chc12@chonnam.ac.krsup> ; Sung Man Lee<sup>csup> ; Hoon Hwang<sup>asup> ; Yeon Uk Jeong<sup>dsup> ; Young Mee Jung<sup>asup><sup> ; sup><sup>ymjung@kangwon.ac.krsup>
- 关键词：Li-ion battery ; Overcharge ; Raman spectroscopy ; X-ray absorption spectroscopy ; 2D hetero-spectral correlation spectroscopy
- 刊名：Vibrational Spectroscopy
- 出版年：2012
- 期刊代码：113_09242031
- 类别：ms
- 出版时间：May, 2012
- 卷：60
- 期：Complete
- 页码：226-230
- 文件大小：370 K
摘要
We investigated an electrochemical reaction on the cathode surface of an overcharged Li[Ni<sub>0.45sub>Co<sub>0.18sub>Mn<sub>0.25sub>Al<sub>0.12sub>]O<sub>2sub>/Li system at the molecular level by using Raman, X-ray absorption spectroscopy (XAS), and 2D hetero-spectral correlation analyses. Changes in the Raman spectra during the overcharging process showed that variations in the local atomic environment occurred with increasing extraction of Li<sup>+sup> ions. XAS spectra obtained during the overcharging process showed that oxidized transition metals coexisted with inoxidizable transition metals. Additionally, synchronous 2D hetero-spectral Raman/XAS correlation spectra clearly elucidated the correlation between the Raman and XAS bands, confirming their band assignments.