The electrochromic characteristics of titanium oxide films prepared by reactive thermal evaporation and ion-assisted deposition have been investigated. It is found that their properties depend on the deposition and post-annealing process, and there is slight conflict between charge capacity and cyclic stability. With a compromise, a TiO2 film with above 7.6 mC cm(-2) Li+ ion capacity and above 10(6) color/bleach cycles is gained. The film is deposited at 50 similar to 80 degrees C substrate temperature and 250 similar to 260 degrees C post-annealing in an oxidizing atmosphere. With the post-annealed TiO2 film as the counter electrode, durable electrochromic devices, glass/ITO/TiO2/PPG-PMMA-LiClO4/WOx/ITO, are obtained.