Thin films of CeVO 4 prepared via the sol-gel route, with a tetragonal (I4 1 /amd) crystalline structure, show good ion-storage properties. The sol-gel route combined with the dip-coating deposition technique allowed thin solid films and powders with a specific Ce/V molar ratio (Ce/V=2:1, 1:1 (CeVO 4 ), 1:2) to be made. The structure of films and powders prepared at 400 o C, and at different times of heat-treatment, was determined using X-ray diffractometry (XRD). It is shown that films containing more ceria than vanadia (Ce/V>1) are nanocrystalline with a CeO 2 grain size up to 100 9, but a tetragonal CeVO 4 (Wakefieldite) phase is formed when the Ce/V molar ratio is 1:1. By using cyclic voltammetry it was possible to observe the Ce 4 + /Ce 3 + and V 5 + /V 4 + redox changes occurring in the films, while in-situ UV-VIS spectroelectrochemical measurements confirmed the sole presence of V 5 + /V 4 + redox changes in tetragonal CeVO 4 films. The small (~0.1-0.5 cm 2 /C) coloration efficiency of CeVO 4 films suggests their utilization as counter electrodes in electrochromic (EC) devices. Comparison of the IR transmission spectra of as-deposited CeVO 4 with CeVO 4 films charged to x 0.9 revealed that besides A 2 u and E u modes - attributed to the VO 4 3 - stretching vibrations predicted by factor group analysis, the Raman active E g and B 2 g modes appear in IR spectra. This suggests that inserted Li + ions occupy the accessible sites within the structure resulting in the loss of inversion symmetry and the consequent disappearance of the distinction between g and u modes. Charging to x 2.3 causes instability of the film structure.