Patent attributes
Electrolyte solutions for electrochromic devices such as rear view mirrors and displays with low leakage currents are prepared using inexpensive, low conductivity conductors. Preferred electrolytes include bifunctional redox dyes and molten salt solvents with enhanced stability toward ultraviolet radiation. The solvents include lithium or quaternary ammonium cations, and perfluorinated sulfonylimide anions selected from trifluoromethylsulfonate (CF3SO3−), bis(trifluoromethylsulfonyl)imide ((CF3SO2)2N−), bis(perfluoroethylsulfonyl)imide ((CF3CF2SO2)2N−) and tris(trifluoromethylsulfonyl)methide ((CF3SO2)3C−). Electroluminescent, electrochromic and photoelectrochromic devices with nanostructured electrodes include ionic liquids with bifunctional redox dyes. Some of the electrolyte solutions color to red when devices employing the solutions are powered, leading to red or neutral electrooptic devices.