Abstract: Lithium was inserted electrochemically from an electrolyte into V₂O₅ thin films prepared by evaporation and posttreated at different temperatures in air
so that Li_xV₂O₅ was obtained. Li⁺ storage properties, reversibiliy of Li⁺ intercalation/deintercalation in V₂O₅ thin films and influence of
Li⁺ insertion on their optical properties were investigated. The experimental results show that two factors, the V⁵⁺ concentration and the sum total of
sites in V₂O₅ thin films, control the capacity of Li⁺ insertion into V₂O₅ thin films, and that these thin films have a good Li⁺ storage characteristic,
stability and reversibility.

Key words: thin film, V₂O₅, electrochemistry, electrochromism