The change in structure of vanadium pentoxide due to the discharge/charge profess of V2O5 prepared by the ozone oxidation method (O-3-V2O5) was studied using an in situ X-ny diffraction technique. The diffraction peaks of (600), (020), (420) and (710) shifted to lower angles as Li+ intercalation progressed until about x=0.8. Then they disappeared and a new broad peak appeared at 47 degrees, which means that lattice extension and structure change occurred. When the O-2-V2O5 was discharged to x=1.8 and then charged, the XRD pattern recovered to almost its initial pattern. The change in the chemical diffusion coefficient (D) for O-3-V2O5 measured using the GIT and the AC techniques closely corresponded to the behavior observed using the in situ XRD technique, i.e, the change in diffusion coefficient levelled at about x=0.8, but after that the value Of D decreased. The changes in the chemical diffusion coefficients of other types of V2O5 (orthorhombic, electrochemically prepared and amorphous V2O5) were also measured and their changes due to Li+ intercalation are discussed.