Electrode of nickel oxide intercalated with lithium ions and electrochromic devices which incorporate such an electrode.

A nickel oxide electrode, interlaced with lithium ions, is obtained by: - ​​vacuum evaporation of nickel oxide (Ni2O3) under vacuum and depositing a nickel oxide film on a conducting glass substrate in which the atomic ratio between nickel and oxygen varies from 0.7 / 1 to 0.9 / 1, up to a thickness of 100 nm; and - activating the thin film of nickel oxide by electrochemical interleaving of a quantity of lithium ions with a charge of 100 to 1,000 C / m2. - An electrocromic window is described comprising: - (a) a tungsten oxide electrode (WO3) on a transparent and conductive glass plate; (b) an electrode of nickel oxide activated for electrochemical lithium intercalation on a transparent and conductive glass plate;