In Situ Raman Spectro-electrochemistry for Cathode Materials in High Voltage Lithium Secondary Batteries

摘要

In Situ Raman spectroscopy has been used for monitoring electrogenerated reactive intermediates, as well as adsorbates on metal, carbon, transition metal oxide surfaces. Since anode and cathode for battery active materials do not always support the SERS (Surface Enhanced Raman Scattring) enhancement, which is a large factor in surface enhanced Raman spectroscopy, In Situ Raman spectroelectrochemistry of battery active materials depends on very sensitive spectrometer system incorporating multichannel detectors. In Situ Raman spectroelectrochemistry is powerful tool for investigating electrochemical energy conversion interfaces. Authors have described electrochemical reactions in lithium ion battery anode and cathode by In Situ Raman spectroelectrochemistry. This combination has directed to be very advantageous in studying reaction occurring at the interfacial reaction field between electrode and electrolyte solutions. We have carried out In Situ Raman spectroelectrochemistry for energy conversion interfaces between electrolyte solutions and cathode electrodes for lithium secondary battery. In this paper, we present here the dynamical motion of the battery cathode active materials; the structural and electronic changes of LiCoO_2 and LiMn_2O_4 on highly electrode potentials.