Electrochromic devices based on lithium insertion

• US 20040021921A1
• Filed: 05/19/2003
• Published: 02/05/2004
• Est. Priority Date: 05/17/2002
• Status: Active Grant

• Current Assignee: Regents of the University of California (University of California)
• Original Assignee: Regents of the University of California (University of California)
• Inventors: Richardson, Thomas J.
• Granted Patent: US 7,042,615 B2
• Time in Patent Office: Days
• US Class Current: 359/196
• CPC Class Codes: G02F 1/1524 Transition metal compounds

Abstract

Electrochromic devices having as an active electrode materials comprising Sb, Bi, Si, Ge, Sn, Te, N, P, As, Ga, In, Al, C, Pb, I and chalcogenides are disclosed. The addition of other metals, i.e. Ag and Cu to the active electrode further enhances performance.

Claims

1. A switching device capable of undergoing a reversible change in light transmittance or reflectance, comprising:

a counter electrode, an electrolyte layer and an active electrode, wherein;

said electrolyte layer is disposed between the counter electrode the active electrode,

said electrolyte layer comprising either an alkali or alkaline earth metal; and

said active electrode comprises at least one element chosen from the group consisting of Sb, Bi, Si, Ge, Sn, Te, N, P, As, Ga, In, Al, C, Pb and I.

2. The switching device as claimed in claim 1,

wherein the alkali metal is Li.

3. The switching device as claimed in claim 2,

wherein upon the application of a current to the switching device the active electrode comprises a compound selected from the group consisting of Li₂Sb, Li₃Sb, Li₂Bi and Li₃Bi.

6. The switching device as claimed in either of claims 1, 2 or 3, further comprising:

a glass layer and a transparent conducting oxide layer disposed between the glass layer and the counter electrode.

11. The switching device as claimed in claim 1, wherein:

the active electrode comprises either Ag or Cu in an amount of from about 1 wt % to about 70 wt %.

12. The switching device as claimed in claim 1, wherein:

the active electrode comprises either Ag or Cu in an amount of from about 12 wt % to about 50 wt %.

4. A switching device capable of undergoing a reversible change in light transmittance or reflectance, comprising:

a counter electrode, an electrolyte layer and an active electrode;

wherein

said electrolyte layer is disposed between the counter electrode and the active electrode, said electrolyte layer comprising either an alkali or alkaline earth metal;

and said active electrode comprises a transition metal chalcogenide.

5. The switching device as claimed in claim 4,

wherein the electrolyte comprises Li.

7. The switching device as claimed in either of claims 4 or 5, further comprising:

a glass layer and a transparent conducting oxide layer disposed between the glass layer and the active electrode.

8. The switching device as claimed in claim 4, wherein:

the active electrode is chosen from the group consisting of TiS₂, NbSe₂, and NbTe₂.

9. The switching device as claimed in claim 4, wherein:

the active electrode comprises either Ag or Cu in an amount of from about 1 wt % to about 70 wt %.

10. The switching device as claimed in claim 4, wherein:

the active electrode comprises either Ag or Cu in an amount of from about 12 wt % to about 50 wt %.