Structural models for nickel electrode active mass

Raman spectroscopic data allow one to distinguish nickel electrode active mass, alpha- and beta-phase materials. Discharged active mass is not isostructural with beta-Ni(OH)2. This is contrary to the generally accepted model for the discharged beta phase of active mass. It is concluded that charged active mass displays a disordered and nonstoichiometric, non-closepacked structure of the , NiOOH structure type. Raman spectral data and X-ray diffraction data are analyzed and shown to be consistent with this structural model.