Patent US2731682A successfully refreshed from Google Patents.
Patent US4294893A successfully refreshed from Google Patents.
US4294893A
Expired / Lapsed
US
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Graphite-resin composite electrode structure, and a process for its manufacture
Assignee: Centro Ricerche Fiat SCpA
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Filing: 1979-05-21
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Granted: 1981-10-13
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Expires: 1999-05-21
Abstract
Abstract A composite graphite-resin porous electrode structure is made by intimately mixing powdered graphite with the resin monomers and partially polymerizing and grinding the mixture before forming a moulding composition by adding a pore-forming agent removable by decomposition or leaching to form uniformly-sized pores. A catalyst for the electrode reaction is incorporated in the electrode with the pore-forming agent or in a thin layer during moulding and an electrically-conductive strengthening element which acts as a rheophore is also incorporated during moulding. Layers having different pore sizes may be formed and a water-repellent film is applied to one face of the electrode.
Inventors
- 👤 Giuliano Iemmi
- 👤 Diego Macerata
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 08:02
CPC Classifications
H; H01; H01M; H01M4/00; H01M4/86; H01M4/96; H01M4/02; H01M4/62; Y; Y02; Y02E; Y02E60/00; Y02E60/10; Y02E60/30; Y02E60/50
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
141 words
A press-formed fuel cell electrode comprising an electrically conductive porous plate portion contoured by an electrically conductive compact carrier frame portion integral with said plate portion, the structure of each of said portions being formed by resin-bonded particles of a conductive carbon, the bonding resin being a cross-linked polyimide resin in an amount of 15-50% while the carbon particles are correspondingly in an amount of 85-50% on the joint weight of the carbon particles and resin, and wherein the porous plate portion has been obtained by a process comprising pressing at cross-linking temperature a particulate mixture of (a) particles of a prepolymer of said polyimide resin filled with said carbon particles and (ii) particles of a pore-forming agent removable by volatilization or leaching, one face of the porous plate portion being coated with sintered particles of polytetrafluoroethylene rendering said face hydrophobic.
Claim 2
Dependent Claim
141 words
A press-formed fuel cell electrode comprising an electrically conductive porous plate portion contoured by an electrically conductive compact carrier frame portion integral with said plate portion, the structure of each of said portions being formed by resin-bonded particles of a conductive carbon, the bonding resin being a cross-linked polyimide resin in an amount of 15-50% while the carbon particles are correspondingly in an amount of 85-50% on the joint weight of the carbon particles and resin, and wherein the porous plate portion has been obtained by a process comprising pressing at cross-linking temperature a particulate mixture of (a) particles of a prepolymer of said polyimide resin filled with said carbon particles and (ii) particles of a pore-forming agent removable by volatilization or leaching, one face of the porous plate portion being coated with sintered particles of polytetrafluoroethylene rendering said face hydrophobic.
Claim 3
Dependent Claim
30 words
The electrode of claim 1, wherein the polyimide resin is the reaction product of 4,4'-carbonyl diphthalic anhydride and 5-norbornane-2,3-dicarboxyl anhydride in 1:1 molar ratio with stoichiometrically equivalent amount of diamino-diphenyl-methane.
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) | 1984-10-12 | 1985-04-13 | 1985-10-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-10-12 | 1989-04-13 | 1989-10-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-10-12 | 1993-04-13 | 1993-10-13 | $7700.00 | Window Closed / Lapsed |