Patent US3655845A successfully refreshed from Google Patents.
US3655845A
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Heating a sintered alumina article in atmosphere containing sodium or potassium ions
Assignee: Toyota Central R&D Labs Inc
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Filing: 1969-07-29
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Granted: 1972-04-11
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Expires: 1989-07-29
Abstract
Abstract A METHOD FOR PRODUCING A PERMEABLE PRODUCT OF THE BETA-ALUMINA TYPE CAPABLE OF PASSING SODIUM AND/OR POTASSIUM IONS AND PRIMARILY USEFUL AS THE SEPARATOR IN A BATTERY CELL, COMPRISING THE STEPS OF FROMING AN ALPHAALUMINA SINTERED MEMBER INTO A DESIRED SHAPE, PLACING SAID SINTERED MEMBER IN AN ALKALI METAL ATMOSPHERE, E.G., SODIUM POTASSIUM, OR OXIDES THEREOF AT AN ELEVATED TEMPERATURE, AND DIFFUSING THE ALKALI METAL OR ITS OXIDE INTO SAID ALPH-ALUMINA MEMBER, WHEREBY TO FORM AN ION PERMEABLE SEPARATOR HAVING A DENSE STRUCTURE AND SUFFICIENT STRENGTH FOR ITS INTENDED USE.
Inventors
- 👤 Takewo Chiku
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 20:47
CPC Classifications
C; C04; C04B; C04B41/00; C04B41/009; C04B35/00; C04B35/01; C04B35/10; C04B35/111; C04B35/113; C04B41/45; C04B41/50; C04B41/80; C04B41/81; C04B41/85; H; H01; H01M; H01M10/00; H01M10/36; H01M10/39; H01M10/3909; H01M10/3918; Y; Y02; Y02E; Y02E60/00; Y02E60/10
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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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) | 1975-04-11 | 1975-10-11 | 1976-04-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-04-11 | 1979-10-11 | 1980-04-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-04-11 | 1983-10-11 | 1984-04-11 | $7700.00 | Window Closed / Lapsed |