Investigation of the position of Li+ ions in a polyacrylonitrile-based electrolyte by Raman and infrared spectroscopy

✍ Scribed by Zhaoxiang Wang; Biying Huang; Hong Huang; Liquan Chen; Rongjian Xue; Fosong Wang

• Publisher: Elsevier Science
• Year: 1996
• Tongue: English
• Weight: 365 KB
• Volume: 41
• Category: Article
• ISSN: 0013-4686
• DOI: 10.1016/0013-4686(95)00392-4

✦ Synopsis

The Raman spectra of polyacrylonitrile (PAN) and/or lithium perchlorate (LiClO,) complex containing plasticizer ethylene carbonate and the infrared spectra of the polymer electrolytes with different mass ratios of PAN to LiClO, have been studied. It has been found that the lithium ions strongly interact with the C=N groups of PAN. However, at the ordinarily used content, say, the concentration of Li* ions is as low as 5X, because of the high intensity of the characteristic vibration of the C'N group of PAN, it is very difficult to observe the interaction between the ions and the molecules. When the content of LiCIO, is raised to a certain extent, this interaction can be detected by way of Raman and IR spectroscopy.

In both the Raman and IR spectra of the system of EC/PAN/LiCIO, with various mass ratios of PAN and LiCIO,, a striking shoulder was observed at about 2270cm-'. By comparing the spectra of the system with that of EC/PAN and EC/LiCIO,, the new shoulder was assigned to the interaction between Li' ions and the CEN groups of the PAN molecules.