Development of electrochromic devices working with hydrophobic lithium electrolyte

This manuscript report on a new lithium electrolyte, allowing the manufacturing of electrochemical systems, such as electrochromic devices, in ambient atmosphere. It is based on lithium bis-trifluoromethane sulfommide dissolved in the following hydrophobic salt, which was first prepared by M. Grätzel et al.: 1-ethyl. 3-methyllimidazolium bis-trifiuoromethane sulfonmide. We have also successfully tested the compatibility of this electrolyte with WO₃ and TiO₂-CeO₂ films acting respectively as efficient electrochromic electrode and counter electrode for smart-window working with Li⁺ions.