Electrochromic element, materials for use in such element, processes for making such element and such materials and use of such element in an electrochromic glass device
PCT No. PCT/US90/03873 Sec. 371 Date Mar. 12, 1992 Sec. 102(e) Date Mar. 12, 1992 PCT Filed Jul. 13, 1990 PCT Pub. No. WO91/01510 PCT Pub. Date Feb. 7, 1991.An electrochromic element useful in an electrochromic glass or mirror device and a process for making such element. The element is a five-layered structure including an electrolyte ion conducting layer interposed between first and second inorganic electrochromic layers which are interposed between a pair of conductive electrodes. The second inorganic electrochromic layer is amorphous. The first and second inorganic electrochromic layers are different and are capable of exhibiting color-forming properties complementary to one another upon the incorporation of at least one H, Li, Na, K, Ag, Cu or Tl ion. The electrolyte ion conducting layer may be a copolymer of ethylene oxide, butylene oxide or methyl glycidyl ether, and optionally a small amount of allyl glycidyl ether, along with an ionizable salt, or may be a polyurethane gel formed by reacting the copolymer with triisocyanate, along with an ionizable salt. The second inorganic electrochromic layer comprises a transition element chalconide or halide which exhibits a color change when shifting between the +2 and +3 valence states or between the +3 and +4 valence states. The second inorganic electrochromic layer may be produced by an electrochemical process, a chemical process, a physical process or by a solid state process. The electrochromic element may also comprise a plurality of five-layer structures in tandem, each pair separated by a substrate. The electrochromic element of the invention is also useful as a supercapacitor.