Lattice vibrations of materials for lithium rechargeable batteries. VI: Ordered spinels

Raman scattering spectra have been investigated to evaluate the local structure of lithiated oxides used as electrode materials for lithium-ion batteries. We report the analysis of the vibrational spectra of ordered spinel phases including the partially delithiated λ-Li0.5Mn2O4 (F4¯3m SG), the partial charge-ordered LiMn2O4 orthorhombic form (Fddd SG) and the LiNi0.5Mn1.5O4 substituted oxide (P4132 SG). Analysis of spectroscopic data is performed using the classical factor group theory and the vibration features are compared with those of the ordered lithium ferrite α-LiFe5O8 and the normal spinels LiMn2O4 and LiNi0.5Mn1.5O4 (Fd3m SG), and the inverse spinel LiNiVO4.