Electrochromic material and electro-optical device using same

Claim 1

An electro-optical device comprising a first substrate, a first electronic contact disposed over said first substrate, a layer comprised of M y CrO 2+x where 0.33≦y≦2.0, x≦2, and M=Li, Na, or K, said M y CrO 2+x coloring on oxidation, a layer comprised of an electrochromic material, said electrochromic material coloring on reduction, a Li + ion conducting layer disposed between said M y CrO 2+x and said reductively coloring electrochromic layer, said M y CrO 2+x layer or said reductively coloring electrochromic layer being disposed on said first electronic contact a second electronic contact disposed over said previous layers wherein, one or both of said M y CrO 2+x and said reductively coloring electrochromic material are partially reduced by electro-active lithium, and whereby said electro-active lithium is distributed between said M y CrO 2+x and said reductively coloring electrochromic layer in a manner determined by the magnitude and polarity of a voltage applied between said electronic contacts, said electro-active lithium distribution determining the optical state of said device.