US3753784A
Expired / Lapsed
US
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Separator for maintenance-free cells
Assignee: Robert Bosch GmbH
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Filing: 1970-09-28
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Granted: 1973-08-21
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Expires: 1990-09-28
Abstract
Abstract A separator for a maintenance-free cell consisting of several layers and being sufficiently porous to serve as the electrolyte holder. At least one of the layers is micro-porous, resistant to migration of heavy metal ions, and proof against short circuits.
Inventors
- 👤 W Eisenacher
- 👤 Roda E Von
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 23:41
CPC Classifications
H; H01; H01M; H01M50/00; H01M50/40; H01M50/409; H01M50/449; H01M50/457; H01M50/489; H01M50/491; Y; Y02; Y02E; Y02E60/00; Y02E60/10
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
39 words
The cell as defined in claim 1, wherein said micro-porous material is selected from the group consisting of silica gel particles held together with a binder, diatomaceous earth held together with a binder, and ribless paper containing a binder.
Claim 2
Dependent Claim
38 words
The cell as defined in claim 1, wherein said fibrous material is selected from the group consisting of glass, polyethylene, polypropylene, polyvinylchloride, polytetrafluoroethylene, polyesters, polyacrylonitrile, modified polyvinylchloride-polyacrylonitrile, cellulose fibers coated with polyethylene, and cellulose fibers coated with polypropylene.
Claim 3
Dependent Claim
18 words
The cell as defined in claim 1, said separator having a thickness between 1 mm and 6 mm.
Claim 4
Dependent Claim
52 words
The cell as defined in claim 1, wherein said microporous material is selected from the group consisting of diatomaceous earth, silica gel and cellulose, bound together with a material selected from the group consisting of natural rubber, isoprene, chloroprene, butadiene styrol, phenolic resins, resins based on cresol and resins based on melamine.
Claim 5
Dependent Claim
19 words
The cell as defined in claim 1, wherein said microporous material has pores with diameters ranging from 1-20 microns.
Claim 6
Dependent Claim
19 words
The cell as defined in claim 1, wherein said microporous material has pores with diameters ranging from 5-15 microns.
Claim 7
Dependent Claim
25 words
A combination as defined in claim 1, at least said third layer of microporous material having a porosity between substantially 50 and substantially 95 percent.
Claim 8
Dependent Claim
25 words
A combination as defined in claim 1, at least said third layer of microporous material having a porosity between substantially 70 and substantially 80 percent.
Claim 9
Dependent Claim
19 words
A combination as defined in claim 1, said fibrous material comprising fibers having a thickness less than 1 micron.
Claim 10
Dependent Claim
24 words
A combination as defined in claim 1, said microporous material comprising fibers having diameters of about 4 microns and lengths of about 100 microns.
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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) | 1976-08-20 | 1977-02-19 | 1977-08-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-08-20 | 1981-02-19 | 1981-08-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-08-20 | 1985-02-19 | 1985-08-21 | $7700.00 | Window Closed / Lapsed |