Flexible and multilayer electrochromic devices and methods of making the same
A monolithic tandem electrochromic device, comprising a central transparent conductor ion blocking layer, a first electrochromic multilayer stack arranged on a first surface of the central transparent conductor ion blocking layer, and a second electrochromic multilayer stack arranged on a second surface of the central transparent conductor ion blocking layer is described. The central transparent conductor ion blocking layer can comprise ion conductivities between 10 −4 and 10 −20 S/cm, and electrical resistivity less than 100 Ohm-cm.
1. A monolithic tandem electrochromic device, comprising:
a central transparent conductor layer;
a first electrochromic multilayer stack arranged on a first surface of the central transparent conductor layer; and
a second electrochromic multilayer stack arranged on a second surface of the central transparent conductor layer, wherein the second electrochromic multilayer stack comprises:
a second transparent conductor layer;
a fourth electrochromic layer arranged on a surface of the second transparent conductor layer;
a second ion conductor layer arranged on a surface of the third electrochromic layer; and
a third electrochromic layer arranged at a surface of the second ion conducting layer;
wherein the third electrochromic layer is adjacent to the second surface of the central transparent conductor layer.
2. The monolithic tandem electrochromic device of claim 1 , wherein the central transparent conductor layer comprises:
a flexible transparent film;
a third transparent conductor layer; and
a fourth transparent conductor layer, wherein the third and fourth transparent conductor layers are arranged on either side of the flexible transparent film, and
wherein the tandem monolithic electrochromic device comprises an electrically conductive member forming an electrical connection between the third and the fourth transparent conductor layers.
3. The monolithic tandem electrochromic device of claim 1 , wherein the central transparent conductor layer material comprises conductive nanowires embedded in a polymer, or conductive nanoparticles embedded in a polymer.
4. The monolithic tandem electrochromic device of claim 1 , wherein the first electrochromic multilayer stack comprises:
a first transparent conductor layer;
a first electrochromic layer arranged on the surface of the first transparent conductor layer;
a first ion conductor layer arranged on the surface of the first electrochromic layer; and
a second electrochromic layer arranged on the surface of the first ion conducting layer;
wherein the second electrochromic layer is adjacent to the first surface of the central transparent conductor layer.
5. The monolithic tandem electrochromic device of claim 4 , wherein the second electrochromic layer comprises an electrochromic cathode layer comprising crystalline cathodic electrochromic nanostructures, wherein the electrochromic cathode layer does not comprise a binder.
6. The monolithic tandem electrochromic device of claim 5 , wherein the third EC layer comprises an electrochromic cathode layer comprising crystalline cathodic electrochromic nanostructures, wherein the electrochromic cathode layer does not comprise a binder.
7. The monolithic tandem EC device of claim 4 , further comprising:
a first outer substrate adjacent to the first transparent conductor layer; and
a second outer substrate adjacent to the second transparent conductor layer,
wherein a first and second outer substrate material comprises glass or plastic.
8. The monolithic tandem EC device of claim 1 , wherein the second transparent conductor layer has resistance to current flow substantially parallel to a major surface of a second electrically conductive layer that varies as a function of position within the second electrically conductive layer.
9. The monolithic tandem EC device of claim 4 , wherein the first transparent conductor layer has resistance to current flow substantially parallel to a major surface of a first electrically conductive layer that varies as a function of position within the first electrically conductive layer.
10. A method of producing a monolithic tandem electrochromic device, comprising:
providing central transparent conductor layer;
providing a first electrochromic multilayer stack;
providing a second electrochromic multilayer stack;
arranging the first electrochromic multilayer stack on a first surface of the central transparent conductor layer; and
arranging the second electrochromic multilayer stack on a second surface of the central transparent conductor layer, wherein the second electrochromic multilayer stack comprises:
a second transparent conductor layer;
a fourth electrochromic layer arranged on the surface of the second transparent conductor layer;
a second ion conductor layer arranged on the surface of the third electrochromic layer; and
a third electrochromic layer arranged on the surface of the second ion conducting layer;
wherein the third electrochromic layer is adjacent to the second surface of the central transparent conductor layer.
11. The method of claim 10 , wherein the central transparent conductor layer comprises a flexible transparent film, and a third and a fourth transparent conductor layer on either side of the flexible transparent film.
12. The method of claim 10 , wherein the central transparent conductor layer comprises conductive nanowires embedded in a polymer, or conductive nanoparticles embedded in a polymer.
13. The method of claim 10 , wherein the first electrochromic multilayer stack comprises:
a first electrochromic layer;
a first ion conducting layer;
a second electrochromic layer; and
a first transparent conductor layer.
14. The method of claim 13 , wherein the second electrochromic layer comprises an electrochromic cathode layer comprising crystalline cathodic electrochromic nanostructures, wherein electrochromic cathode layer does not comprise a binder.
15. The method of claim 14 , wherein the third electrochromic layer comprises an electrochromic cathode layer comprising crystalline cathodic electrochromic nanostructures, wherein electrochromic cathode layer does not comprise a binder.
16. The method of claim 10 , wherein the second transparent conductor layer has resistance to current flow substantially parallel to a major surface of a second electrically conductive layer that varies as a function of position within the second electrically conductive layer.
17. The method of claim 13 , wherein the first transparent conductor layer comprises a resistance to current flow substantially parallel to a major surface of the first electrically conductive layer that varies as a function of position within the first electrically conductive layer.
18. A method of producing a monolithic tandem electrochromic device, comprising:
providing a first electrochromic sub-stack, comprising:
providing a first outer substrate;
depositing a first transparent conductor on a surface of the first outer substrate;
depositing a first EC layer on the surface of the first transparent conductor;
providing a central sub-stack, comprising:
providing central transparent conductor layer;
depositing a second electrochromic layer on one side of the central transparent conductor layer;
depositing a third electrochromic layer on the other side of the central transparent conductor layer;
providing a second electrochromic sub-stack, comprising:
providing a second outer substrate;
depositing a second transparent conductor on a surface of the second outer substrate;
depositing a fourth EC layer on the surface of the second transparent conductor;
coupling the first electrochromic sub-stack to the central sub-stack using a first free-standing ion conducting substrate arranged between the first electrochromic layer and the second electrochromic layer; and
coupling the second electrochromic sub-stack to the central sub-stack using a second free-standing ion conducting substrate arranged between the third electrochromic layer and the second electrochromic layer, to form the monolithic tandem electrochromic device.
19. The method of claim 18 , further comprising:
providing a plurality of crystalline cathodic electrochromic particles; and
size-reducing the crystalline cathodic electrochromic particles by grinding to produce crystalline cathodic electrochromic nanostructures;
wherein the depositing the second electrochromic layer and the depositing the third electrochromic layer comprise coating the crystalline cathodic electrochromic nanostructures onto the central transparent conductor layer.
20. The method of claim 19 , wherein the second electrochromic layer and the third electrochromic layer do not comprise a binder.
21. The method of claim 18 , wherein the central transparent conductor layer comprises a flexible transparent film coated with central transparent conductor layers on both sides.
22. The method of claim 18 , wherein the central transparent conductor layer material comprises conductive nanowires embedded in a polymer, or conductive nanoparticles embedded in a polymer.
23. The method of claim 18 , wherein the connecting the first electrochromic sub-stack to the central sub-stack using the first free-standing ion conducting substrate comprises laminating the first electrochromic sub-stack to the central sub-stack using the first free-standing ion conducting substrate as the lamination layer.
24. The method of claim 18 , wherein the connecting the second electrochromic sub-stack to the central sub-stack using the second free-standing ion conducting substrate comprises laminating the first electrochromic sub-stack to the central sub-stack using the second free-standing ion conducting substrate as the lamination layer.