Aiming to improve electrochromic properties of niobium pentoxide (Nb2O5) there were synthesized new, doped with lithium trifluoromethane sulfonate salt (LiCF3SO3), and vanadium pentoxide (Nb2O5:Li+:V2O5) thin films. A study of these films focused on influence of doping on the electrochromic performance of these films. It was observed that Nb2O5:Li+:V2O5 presents a reversible and fast insertion/extraction kinetics. A maximum charge density for three layers' film was -36.0 mC cm(-2), and it corresponded to spectral transmission change of Delta T = 66%, i.e., variation from 80 to 20% from transparent to colored states.