Patent US4354958A successfully refreshed from Google Patents.
US4354958A
Expired / Lapsed
US
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Fibrillated matrix active layer for an electrode
Assignee: Eltech Systems Corp
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Filing: 1980-10-31
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Granted: 1982-10-19
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Expires: 2000-10-31
Abstract
Abstract The present disclosure is directed to an improved fibrillated matrix-type active layer for an electrode of improved strength and durability and capable of operation at high current density with enhanced resistance to mechanical failure, and to a process for producing such improved active layers. The process is characterized by alternately or simultaneously producing two components; combining the components; shear blending (fibrillating) the mixture; drying; chopping to a fine powder form, and rolling into a self-sustaining, coherent shear form. Alternatively, the active layer can be formed by wet deposition of the powder on a filter paper or like medium. The term "matrix" as used herein means that the active carbon particles are present within an unsintered network of carbon black/PTFE (fibrillated) material.
Inventors
- 👤 Frank Solomon
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 20:01
CPC Classifications
C; C25; C25B; C25B11/00
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
154 words
A method of preparation of matrix active layer for an electrode comprising intimately mixing carbon black particles having a particle size of from about 50 to about 3000 Angstroms and having a surface area of from about 25 to about 300 square meters per gram, with an aqueous dispersion of fibrillatable polytetrafluoroethylene particles; said mixture containing from 65 to about 75 percent carbon black particles and 25 to 35 percent polytetrafluoroethylene by weight; drying said mixture at temperatures in the range from about 250° to 325° C. from 10 to about 90 minutes; combining the thus dried PTFE/carbon black particulate component with deashed active carbon catalyst particles to form an intimate mix said catalyst particles amounting from between 40 to 80 weight percent of the entire mix; fibrillating said intimate mix and forming said fibrillated mixture into an active layer containing active carbon particles present within a network of carbon black and fibrillated polytetrafluoroethylene.
Claim 2
Independent Claim
154 words
A method of preparation of matrix active layer for an electrode comprising intimately mixing carbon black particles having a particle size of from about 50 to about 3000 Angstroms and having a surface area of from about 25 to about 300 square meters per gram, with an aqueous dispersion of fibrillatable polytetrafluoroethylene particles; said mixture containing from 65 to about 75 percent carbon black particles and 25 to 35 percent polytetrafluoroethylene by weight; drying said mixture at temperatures in the range from about 250° to 325° C. from 10 to about 90 minutes; combining the thus dried PTFE/carbon black particulate component with deashed active carbon catalyst particles to form an intimate mix said catalyst particles amounting from between 40 to 80 weight percent of the entire mix; fibrillating said intimate mix and forming said fibrillated mixture into an active layer containing active carbon particles present within a network of carbon black and fibrillated polytetrafluoroethylene.
Claim 3
Dependent Claim
14 words
A method as in claim 1 wherein said carbon black is an acetylene black.
Claim 4
Dependent Claim
13 words
A method as in claim 1 wherein said active carbon particles contain platinum.
Claim 5
Dependent Claim
21 words
A method as in claim 1 wherein said active carbon particles range in size from about 1 to about 30 microns.
Claim 6
Dependent Claim
24 words
A method as in claim 1 wherein the total mix contains from about 25 to about 50 weight percent of a pore-forming bulking agent.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-10-18 | 1986-04-19 | 1986-10-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-10-18 | 1990-04-19 | 1990-10-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-10-18 | 1994-04-19 | 1994-10-19 | $7700.00 | Window Closed / Lapsed |