Vanadium oxide gels can be synthesized either from vanadic acid or vanadium alkoxides. The chemical nature, the structure and the properties of the resulting materials can then be quite different. The aqueous route, or a high hydrolysis ratio, leads to ordered gels with a layered structure. These gels behave as a host structure for intercalation. They exhibit improved properties as reversible cathodes in lithium batteries. Amorphous oxopolymers can be obtained from alkoxide precursors. They lead to optically transparent thin films that can advantageously be used for electrochromic devices. Moreover, the alkoxide route allows the preparation of mixed oxide materials and highly porous aerogels.