The paper discusses the theoretical basis of electrochromism, the concept of electrochromic devices and materials that can be used to create them. Most attention is paid to oxide materials such as WO₃, V₂O₅, TiO₂, Cr₃O₈, NiO, MoO₃. Characteristics of these materials and their preparation methods are shown. The paper presents experimental data on the nickel oxide thin films production using a solution method to be applied without vacuum equipment. It is shown that the obtained and investigated electrochromic material changes the light transmittance upon application of a voltage and can cycling the processes of darkening and discoloration for a long time.