Electrochromic devices

• US 6,266,177 B1
• Filed: 11/18/1999
• Issued: 07/24/2001
• Est. Priority Date: 11/18/1999
• Status: Expired due to Term

• Current Assignee: Donelly Corporation
• Original Assignee: Donnelly Corporation (Magna International Incorporated)
• Inventors: Ingle, Andrew, Kennedy, Steven R., Allemand, Pierre Marc, Yao, Yongjin, Agrawal, Anoop, Boulton, Jonathan M., Cronin, John P., Tonazzi, Juan Carlos Lopez
• Primary Examiner(s): Ben, Loha
• Application Number:
  US09/443,109
• Time in Patent Office: 614 Days
• Field of Search: 359/265, 359/267, 359/269, 359/270, 359/271, 359/272, 359/273, 359/275, 252/500, 252/583, 252/600
• US Class Current: 359/265
• CPC Class Codes: G02F 1/1524 Transition metal compounds
• CPC Class Codes: G02F 1/1525 characterised by a particular ion transporting layer, e.g. electrolyte
• CPC Class Codes: G02F 2001/1555 Counter electrode

Abstract

Electrochromic devices incorporate reversible oxidizers to improve device kinetics, incorporate counterelectrodes composed of an alkali metal oxide and vanadium oxide to improve stability, and doped tungsten or molybdenum oxide in the electrochromic layer to improve UV durability.

Claims

1. A method to enhance the kinetics of an electrochromic device having at least an electrolyte layer comprising an anodic compound and a cathodic electrochromic layer, said method comprising the step of:

adding an augmenting amount of an oxidizer to the electrolyte layer in an amount effective to enhance a bleaching rate of the electrochromic layer.

2. A method to enhance the kinetics of an electrochromic device having at least an electrolyte layer comprising a cathodic compound and an anodic electrochromic layer, said method comprising the step of:

adding an augmenting amount of a reducer to the electrolyte layer in an amount effective to enhance a bleaching rate of the electrochromic layer.

3. An electrochromic device comprising:

two conducting layers, at least one of which is transparent, having at least an electrochromic layer and

an electrolyte layer disposed therebetween, said electrolyte layer containing an augmenting amount of an oxidizer effective to enhance a bleaching rate of said electrochromic layer.

4. The electrochromic device according to claim 3, wherein said electrochromic layer is comprised of WO₃, said electrolyte layer is comprised of ferrocene and said oxidizer is a ferrocenium salt.

5. An electrochromic device comprising:

two conducting layers, at least one of which is transparent, having at least an electrochromic layer and an electrolyte layer disposed therebetween, said electrolyte layer containing an augmenting amount of a reducer effective to enhance a bleaching rate of said electrochromic layer.

6. The electrochromic device according to claim 5, wherein said electrochromic layer is comprised of polyaniline or its derivatives.

7. An electrochromic device exhibiting reduced photochromism, said electrochromic device comprising:

a first conducting layer and a second conducting layer, at least one of said conducting layers being transparent

an electrochromic layer formed from an oxide of tungsten or molybdenum disposed between the first and second conducting layers; and

a photochromism reducing layer disposed between the transparent conducting layer and the electrochromic layer, formed from an oxide of tungsten or molybdenum doped with at least one of lithium, sodium, or potassium, cobalt, chromium, copper or barium.

8. The electrochromic device according to claim 7, wherein said photochromism reducing layer has a thickness from about 5 nm to about 100 nm.

9. An electrochromic device exhibiting reduced photochromism, compared to a device without a layer of an oxide of M₂, said electrochromic device comprising:

a first conductor layer and a second conductor layer, at least one of said conductor layers being transparent;

an electrochromic layer formed from an oxide of tungsten or molybdenum disposed between said first and second conductor layers; and

a photochromism reducing layer disposed between the transparent conductor layer and the electrochromic layer, said photochromism reducing layer formed from an oxide of M₂, effective to reduce photochromism, wherein M₂ is an element of Group 2A or an element of the 4^th period in a standard periodic table of the elements.

10. The electrochromic device according to claim 9, wherein said photochromism reducing layer has a thickness from about 5 nm to about 100 nm.

11. The electrochromic device according to claim 9, wherein M₂ is at least one of barium, vanadium, chromium, cobalt, or copper.

12. An electrochromic device comprising a UV resistant electrochromic layer disposed between two conductor layers, at least one of which is transparent, said electrochromic layer formed from a composition described by formula:

13. The electrochromic device according to claim 12, wherein the atomic ratio p/r of M₁ to M₃ is in the range of from about 0.1 to about 1.

14. The electrochromic device according to claim 12, wherein the atomic ratio q/r of M₂ to M₃ is in the range of from about 0.01 to about 0.2.

15. An electrochromic device comprising a UV resistant electrochromic layer disposed between two conducting layers, at least one of which is transparent, said electrochromic layer formed from a composition described by formula:

16. The electrochromic device according to claim 15, wherein the atomic ratio q/r of M₄ to M₃ is in the range of from about 0.01 to about 0.2.

17. An electrochromic device comprising two conducting layers, at least one of which is transparent, having disposed therebetween an electrochromic layer and a counterelectrode where the counterelectrode is formed from a composition described by formula:

18. The electrochromic device according to claim 17, wherein M₅ is at least one of lithium, sodium, or potassium.

19. An electrochromic device comprising two conducting layers, at least one of which is transparent, having disposed therebetween an electrochromic layer and a counterelectrode formed from a composition described by formula:

20. The electrochromic device according to claim 19, wherein M₅ is at least one of lithium, sodium, or potassium.

21. An electrochromic device comprising two conducting layers, at least one of which is transparent, having disposed therebetween an electrochromic layer and a counterelectrode formed from a composition described by formula:

22. An electrochromic device comprising two conducting layers, at least one of which is transparent, having disposed therebetween (i) an electrochromic layer comprised of at least one of tungsten oxide, molybdenum oxide and niobium oxide and (ii) a counterelectrode comprised of an inorganic oxide matrix with a dye incorporated therein.

23. An electrochromic device comprising two conducting layers, at least one of which is transparent, having disposed therebetween (i) an electrochromic layer comprised of conductive polymer and (ii) a counterelectrode comprised of an inorganic oxide matrix with a dye incorporated therein.

24. The electrochromic device according to claim 23, wherein said conductive polymer is polyaniline or a derivative thereof.

25. A counterelectrode for an electrochromic device comprising at least one inorganic oxide and an incorporated dye, wherein said counterelectrode has a haze of less than 1% as measured by ASTM method D1003.