Patent US4252872A successfully refreshed from Google Patents.
US4252872A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Granulated lead oxides with teflon
Assignee: YERMCO Inc
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Filing: 1980-02-14
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Granted: 1981-02-24
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Expires: 2000-02-14
Abstract
Abstract An improvement in the production of tube electrodes for lead storage batteries comprising mixing a small amount (0.1 to 3 weight percent) of polytetrafluoroethylene (PTFE) with lead powder, the mixture is heated and shear stresses are applied thereto sufficient to convert substantially all of the PTFE in the mixture to fibrous form and to form a non-powdery dough. The dough is then granulated and the doughy granules about 100μ to 500μ in major dimension are used for filling tube elctrodes of a lead-acid storage battery.
Inventors
- 👤 Ove Nilsson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 09:21
CPC Classifications
H; H01; H01M; H01M4/00; H01M4/02; H01M4/14; H01M4/16; H01M4/36; H01M4/48; H01M4/56; Y; Y02; Y02E; Y02E60/00; Y02E60/10; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49108
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
106 words
A method for the production of a tube-type electrode for a lead-acid storage battery comprising applying heat and shear forces to a mixture of lead powder which normally is at least 65% oxidized and from 0.1 to 3 percent by weight of polytetrafluoroethylene to convert said polytetrafluoroethylene into fibrous form and produce a polytetrafluoroethylene - lead powder dough, mechanically granulating said dough to form granules having major dimensions of about 100 to about 500μ and, thereafter positioning said granules in the space between an insulative tube and an electroconductive spine of a tube-electrode structure to provide material convertible in-situ to a polytetrafluoroethylene fiber-bound, battery active mass.
Claim 2
Independent Claim
106 words
A method for the production of a tube-type electrode for a lead-acid storage battery comprising applying heat and shear forces to a mixture of lead powder which normally is at least 65% oxidized and from 0.1 to 3 percent by weight of polytetrafluoroethylene to convert said polytetrafluoroethylene into fibrous form and produce a polytetrafluoroethylene - lead powder dough, mechanically granulating said dough to form granules having major dimensions of about 100 to about 500μ and, thereafter positioning said granules in the space between an insulative tube and an electroconductive spine of a tube-electrode structure to provide material convertible in-situ to a polytetrafluoroethylene fiber-bound, battery active mass.
Claim 3
Dependent Claim
19 words
The method of claim 1 wherein the amount of polytetrafluoroethylene employed is about 0.25% to about 0.7% by weight.
Claim 4
Dependent Claim
10 words
A tube-type electrode made by the process of claim 1.
References Cited (Backward Citations)
US571143A
Cited
GB891537A
Cited
US3647546A
Cited
US4025701A
Cited
US4011370A
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US4071946A
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US4110519A
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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) | 1984-02-24 | 1984-08-25 | 1985-02-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-02-24 | 1988-08-25 | 1989-02-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-02-24 | 1992-08-25 | 1993-02-24 | $7700.00 | Window Closed / Lapsed |