In situ EXAFS study of nickel hydroxide electrodes during discharge

Abstract

The energy dispersive EXAFS technique has been used to determine the structure of a nickel hydroxide film in situ during the discharge process. Each measurement of the nickel K-edge absorption took approximately 150 s so that the process could be followed accurately. We report changes in the energy of the nickel edge, which gives the charge state of nickel ions in the electrode, and changes in the local structure around the nickel atoms during the discharge process. These variations are correlated with the total charge on the electrode.