Solid dry electrochromic display

• US 4,150,879 A
• Filed: 11/12/1976
• Issued: 04/24/1979
• Est. Priority Date: 11/12/1976
• Status: Expired due to Term

• Current Assignee: Texas Instruments, Inc.
• Original Assignee: Texas Instruments, Inc.
• Inventors: Bayard, Michel L.
• Primary Examiner(s): Miller, Jr., Stanley D.
• Assistant Examiner(s): Davie, James W.
• Application Number:
  US05/741,320
• Time in Patent Office: 893 Days
• Field of Search: 350/160 R, 350/357, 340/324 M, 340/336, 252/408, 252/518
• US Class Current: 359/270
• CPC Class Codes: C09K 9/00 Tenebrescent materials, i.e. materials for which the range of wavelengths for energy absorption is changed as a result of excitation by some form of energy
• CPC Class Codes: G02F 1/1524 Transition metal compounds

Abstract

A totally dry solid electrochromic display cell comprising a tungsten oxide display electrode, a ceramic-like ion conductive electrolyte of a sodium zirconium silicon phosphoric oxide electrolyte and a counter electrode of a sodium "bronze" having a metallic coating.

Claims

1. An electrochromic display cell comprising:

a transparent front panel member of sufficient thickness to act as the structural support substrate of said cell,

a plurality of display electrodes supported on and visible through said front panel and comprised of an oxide of tungsten or vanadium,

a counter-electrode comprised of a sodium tungstate or vanadate;

a dry solid electrolyte interposed between and contacting said display electrodes and said counter-electrode, said electrolyte being electrically insulating but conductive of sodium ions; and

electrical contact means to each of said electrodes.

2. An electrochromic display cell as defined in claim 1 wherein said electrolyte is comprised of a material which is a member of the series Na_1+x Zr₂ Si_x P_3-x O₁₂ and x is from 0.8 to 2.4.

3. An electrochromic display cell as defined in claim 2 wherein x is equal to 2.

4. An electrochromic display cell as defined in claim 1 wherein said display electrode is comprised of WO₃ and said counter-electrode is comprised of Na_y WO₃ and y is about 0.3.

5. An electrochromic display cell as defined in claim 4 wherein said electrolyte is comprised of a material which is a member of the series Na_1+x Zr₂ Si_x P_3-x O₁₂ and x is from 0.8 to 2.4.

6. An electrochromic display cell as defined in claim 1 wherein said display electrode is comprised of WO₃, said counter-electrode is comprised of Na₀.3 WO₃ and said electrolyte is comprised of Na₃ Zr₂ Si₂ PO₁₂.