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US4861345A
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Method of bonding a conductive layer on an electrode of an electrochemical cell
Assignee: Siemens Energy Inc
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Filing: 1988-05-13
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Granted: 1989-08-29
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Expires: 2008-05-13
Abstract
Abstract A dense, electronically conductive interconnection layer 26 is bonded onto a porous, tubular, electronically conductive air electrode structure 16, optionally supported by a ceramic support 22, by (A) providing an air electrode surface, (B) forming on a selected portion of the electrode surface 24, without the use of pressure, particles of LaCrO 3 doped with an element selected from the group consisting of Sr, Mg, Ca, Ba, Co, and mixtures thereof, where the particles have a deposit on their surface comprising calcium oxide and chromium oxide; (C) heating the particles with the oxide surface deposit in an oxidizing atmosphere at from 1,300° C. to 1,550° C., without the application of pressure, to provide a dense, sintered, interconnection material 26 bonded to the air electrode 16, where calcium and chromium from the surface deposit are incorporated into the structure of the LaCrO 3 . A solid electrolyte layer 18 can be applied to the uncovered portion of the air electrode, and a fuel electrode 20 can be applied to the solid electrolyte, to provide an electrochemical cell 10.
Inventors
- 👤 Jeffrey C. Bowker
- 👤 Prabhakar Singh
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 20:55
CPC Classifications
H; H01; H01M; H01M4/00; H01M4/02; H01M4/06; H01M4/08; H01M4/86; H01M4/88; H01M4/8878; H01M4/8882; H01M4/8885; C; C23; C23C; C23C16/00; C23C16/02; C23C16/0272; C23C16/22; C23C16/30; C23C16/40; H01M8/00; H01M8/02; H01M8/0202; H01M8/0204; H01M8/0215; H01M8/0217; H01M8/0219; Y; Y02; Y02E; Y02E60/00; Y02E60/30; Y02E60/50; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49108; Y10T29/49115
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
130 words
A method of bonding a dense, electronically conductive layer on a porous, electronically conductive electrode structure comprising the steps: (A) providing an electrode surface; (B) forming, on a selected portion of the electrode surface, without the application of pressure, particles of LaCrO 3 doped with an element selected from the group consisting of Sr, Mg, Ca, Ba, Co, and mixtures thereof, where the particles have a deposit on their surface comprising calcium oxide and chromium oxide; (C) heating the particles with the oxide surface deposit in an oxidizing atmosphere at from 1,300° C. to 1,550° C., without the application of pressure, to provide a dense, sintered, interconnection material bonded to the electrode, where calcium and chromium from the surface deposit are incorporated into the structure of the LaCrO 3 .
Claim 2
Independent Claim
130 words
A method of bonding a dense, electronically conductive layer on a porous, electronically conductive electrode structure comprising the steps: (A) providing an electrode surface; (B) forming, on a selected portion of the electrode surface, without the application of pressure, particles of LaCrO 3 doped with an element selected from the group consisting of Sr, Mg, Ca, Ba, Co, and mixtures thereof, where the particles have a deposit on their surface comprising calcium oxide and chromium oxide; (C) heating the particles with the oxide surface deposit in an oxidizing atmosphere at from 1,300° C. to 1,550° C., without the application of pressure, to provide a dense, sintered, interconnection material bonded to the electrode, where calcium and chromium from the surface deposit are incorporated into the structure of the LaCrO 3 .
Claim 3
Dependent Claim
36 words
The method of claim 1, where the weight ratio of calcium oxide:chromium oxide is from 0.4 to 9.0:1 and the weight ratio of calcium oxide and chromium oxide:doped LaCrO 3 particles is from 0.005 to 0.10:1.
Claim 4
Dependent Claim
40 words
The method of claim 1, where the electrode is an air electrode, a solid electrolyte is applied to the uncovered portion of the air electrode, and a fuel electrode is applied to the solid electrolyte, to provide an electrochemical cell.
Claim 5
Independent Claim
166 words
A method of bonding a dense, electronically conductive interconnection layer on a porous, tubular, electronically conductive air electrode structure comprising the steps: (A) providing an air electrode surface; (B) depositing, on a selected portion of the air electrode surface, without the application of pressure, a mixture of: (1) particles of LaCrO 3 doped with an element selected from the group consisting of Sr, Mg, Ca, Ba, Co, and mixtures thereof, and (2) a salt solution comprising calcium and chromium, capable of forming oxides upon heating; (C) heating the mixture up to 800° C. so that the particles have a deposit on their surface comprising calcium oxide and chromium oxide; (D) continuing heating the particles with the oxide surface deposit, in an oxidizing atmosphere up to from 1,300° C. to 1,550° C., without the application of pressure, to provide a dense, sintered, interconnection material bonded to the air electrode, where calcium and chromium from the surface deposit are incorporated into the structure of the LaCrO 3 .
Claim 6
Independent Claim
166 words
A method of bonding a dense, electronically conductive interconnection layer on a porous, tubular, electronically conductive air electrode structure comprising the steps: (A) providing an air electrode surface; (B) depositing, on a selected portion of the air electrode surface, without the application of pressure, a mixture of: (1) particles of LaCrO 3 doped with an element selected from the group consisting of Sr, Mg, Ca, Ba, Co, and mixtures thereof, and (2) a salt solution comprising calcium and chromium, capable of forming oxides upon heating; (C) heating the mixture up to 800° C. so that the particles have a deposit on their surface comprising calcium oxide and chromium oxide; (D) continuing heating the particles with the oxide surface deposit, in an oxidizing atmosphere up to from 1,300° C. to 1,550° C., without the application of pressure, to provide a dense, sintered, interconnection material bonded to the air electrode, where calcium and chromium from the surface deposit are incorporated into the structure of the LaCrO 3 .
Claim 7
Dependent Claim
36 words
The method of claim 4, where the weight ratio of calcium oxide:chromium oxide is from 0.4 to 9.0:1 and the weight ratio of calcium oxide and chromium oxide:doped LaCrO 3 particles is from 0.005 to 0.10:1.
Claim 8
Dependent Claim
61 words
The method of claim 4, where the doped LaCrO 3 has the chemical formula La 1-x M x CrO 3 , where M is a dopant element selected from the group consisting of Sr, Mg, Ca, Ba, Co, and mixtures thereof, x=0.075 to 0.25, and the air electrode is comprised of doped oxides or mixtures of oxides of the perovskite family.
Claim 9
Dependent Claim
74 words
The method of claim 4, where, in step (D), during continued heating the calcium oxide and chromium oxide initially melt at approximately 1,050° C. to 1,250° C., completely cover the doped LaCrO 3 particles, and flow into voids between the particles, and as the temperature is raised to from 1,300° C. to 1,550° C., doped LaCrO 3 near the melt dissolves into the melt and then solidifies after step (D) substantially filling the voids.
Claim 10
Dependent Claim
23 words
The method of claim 4, where the calcium oxide and chromium oxide are a mixture of CaO plus Cr 2 O 3 .
Claim 11
Dependent Claim
19 words
The method of claim 4, where the salt solution deposited in step (B) is calcium nitrate plus chromium nitrate.
Claim 12
Dependent Claim
34 words
The method of claim 4, where a solid electrolyte is applied to the uncovered portion of the air electrode, and a fuel electrode is applied to the solid electrolyte, to provide an electrochemical cell.
References Cited (Backward Citations)
US4547437A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-08-28 | 1993-02-27 | 1993-08-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-08-28 | 1997-02-27 | 1997-08-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-08-28 | 2001-02-27 | 2001-08-29 | $7700.00 | Window Closed / Lapsed |