Lattice vibrations of materials for lithium rechargeable batteries - II. Lithium extraction-insertion in spinel structures

Lithiated spinel manganese oxides with various amounts of lithium have been prepared through solid-state reaction and electrochemical intercalation and deintercalation. Local structure of the samples are studied using Raman scattering and Fourier transform infrared spectroscopy. We report vibrational spectra of lithiated manganese oxides LixMn2O4 as a function of lithium concentration in the range 0.1 less than or equal to x less than or equal to 2.0. Raman and Fourier transform infrared (FTIR) spectral results indicated multiple-phase reactions when the lithium content is modified in the spinel lattice. Lattice dynamics of lithiated spinel manganese oxides have been interpreted using either a classical factor-group analysis or a local environment model. The structural modifications have been studied on the basis of vibrations of LiO4 tetrahedral and MnO6 octahedral units when Li/Mn less than or equal to 0.5, and LiO4, LiO6, and MnO6 structural units when Li/Mn > 0.5. (C) 2003 Elsevier B.V. All rights reserved.