Patent US4851377A successfully refreshed from Google Patents.
US4851377A
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US
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Fuel cell, a fuel cell electrode, and a method for making a fuel cell electrode
Assignee: UTC Power Corp
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Filing: 1988-04-15
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Granted: 1989-07-25
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Expires: 2008-04-15
Abstract
Abstract A fuel cell electrode having a non-uniform catalyst loading is disclosed. The electrode has a layer of a hydrophobic polymer and a platinum or platinum alloy catalyst supported on the surface of a porous substrate. The thickness of the layer increases along one axis of the surface so that the electrode has a catalyst loading that increases along the one axis of the surface. A process for making such an electrode having steps of contacting the upper surface of a porous substrate with a mixture of a hydrophobic polymer and a carbon supported catalyst, and establishing a reduced pressure distribution along the lower surface of the porous substrate to cause the catalyst mixture to be deposited as a non-uniform layer on the upper surface of the substrate. A fuel cell utilizing such an electrode is also disclosed.
Inventors
- 👤 Richard D. Breault
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 17:17
CPC Classifications
H; H01; H01M; H01M4/00; H01M4/86; H01M4/8605; H01M4/8663; H01M4/8668; H01M4/88; H01M4/8803; H01M4/8807; H01M4/8825; H01M4/8828; H01M4/8878; H01M4/8896; H01M4/90; H01M4/92; H01M4/921; 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: 9
Claim 1
Independent Claim
116 words
A process for applying a catalyst layer to a surface of a porous substrate to form a fuel cell electrode, said substrate having an upper surface and a lower surface, comprising: contacting the upper surface of the substrate with a mixture comprising a hydrophobic polymer and a catalyst; and establishing a selected distribution of reduced pressure over the lower surface of the porous substrate to cause the mixture to be deposited in a layer of non-uniform thickness on the upper surface of the porous substrate, said thickness increasing along one axis of the upper surface so that the electrode has a catalyst loading per unit area of the upper surface that increases along the one axis.
Claim 2
Dependent Claim
116 words
A process for applying a catalyst layer to a surface of a porous substrate to form a fuel cell electrode, said substrate having an upper surface and a lower surface, comprising: contacting the upper surface of the substrate with a mixture comprising a hydrophobic polymer and a catalyst; and establishing a selected distribution of reduced pressure over the lower surface of the porous substrate to cause the mixture to be deposited in a layer of non-uniform thickness on the upper surface of the porous substrate, said thickness increasing along one axis of the upper surface so that the electrode has a catalyst loading per unit area of the upper surface that increases along the one axis.
Claim 3
Dependent Claim
26 words
The process of claim 1 wherein the mixture additionally comprises an inert carrier gas to form a fluidized mixture and the substrate is an electrode substrate.
Claim 4
Dependent Claim
19 words
The process of claim 1 wherein the mixture additionally comprises water to form an aqueous suspension of flocced particles.
Claim 5
Dependent Claim
12 words
The process of claim 3 wherein the substrate is an electrode substrate.
Claim 6
Dependent Claim
32 words
The process of claim 3 wherein the substrate is a filter medium and the non-uniform layer of catalyst coposition is transferred from the filter medium to a surface of an electrode substrate.
Claim 7
Dependent Claim
16 words
The process of claims 1, 2, 3, 4, or 5 wherein the hydrophobic polymer comprises polytetrafluoroethylene.
Claim 8
Dependent Claim
25 words
The process of claims 1, 2, 3, 4, or 5 wherein the catalyst comprises an alloy of platinum, chromium and cobalt dispersed on carbon particles.
Claim 9
Dependent Claim
19 words
The process of claims 2, 3, 4 or 5 wherein the electrode substrate is porous carbon paper electrode substrate.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-07-24 | 1993-01-23 | 1993-07-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-07-24 | 1997-01-23 | 1997-07-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-07-24 | 2001-01-23 | 2001-07-25 | $7700.00 | Window Closed / Lapsed |