US4121021A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Silver oxide primary cell
Assignee: Panasonic Holdings Corp
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Filing: 1977-07-07
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Granted: 1978-10-17
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Expires: 1997-07-07
Abstract
Abstract A silver oxide primary cell of flat type comprising a casing composed of a cup and a cap electrically insulated from and received in the cup to define a sealed chamber between the cup and the cap. Within the sealed chamber is placed a stack of negative electrode, electrolyte absorbent layer, separator and positive electrode, with the negative and positive electrode held in contact with the cap and the cup, respectively. In order to avoid any possible sharp contact of the positive electrode with the separator, which may otherwise result in internal stresses set up in the separator, the positive electrode has at least one peripheral edge chamfered.
Inventors
- 👤 Hiromichi Ogawa
- 👤 Kenji Inoue
- 👤 Akira Fujiwara
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 13:41
CPC Classifications
H; H01; H01M; H01M6/00; H01M6/04; H01M6/06; H01M6/12; Y; Y02; Y02E; Y02E60/00; Y02E60/10
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
157 words
A silver oxide primary cell of flat type which comprises: a casing composed of a cup and a cap electrically insulated from and received in the cup to define a sealed chamber between the cup and the cap; a positive electrode having a silver oxide as its principal active material; a separator; an electrolyte absorbent layer impregnated with an electrolyte; a negative electrode having zinc as its principal active material; said positive electrode, separator, electrolyte absorbent layer and negative electrode being stacked one above the other in the order given above, the stack being housed within the casing in a manner such that said positive and negative electrodes are held in contact with the cup and the cap, respectively; and at least one of the opposed peripheral edges on the respective surfaces of the positive electrode being chamfered to provide a chamfered edge, the entire area of said chamfered edge being in intimate contact with the separator.
Claim 2
Dependent Claim
157 words
A silver oxide primary cell of flat type which comprises: a casing composed of a cup and a cap electrically insulated from and received in the cup to define a sealed chamber between the cup and the cap; a positive electrode having a silver oxide as its principal active material; a separator; an electrolyte absorbent layer impregnated with an electrolyte; a negative electrode having zinc as its principal active material; said positive electrode, separator, electrolyte absorbent layer and negative electrode being stacked one above the other in the order given above, the stack being housed within the casing in a manner such that said positive and negative electrodes are held in contact with the cup and the cap, respectively; and at least one of the opposed peripheral edges on the respective surfaces of the positive electrode being chamfered to provide a chamfered edge, the entire area of said chamfered edge being in intimate contact with the separator.
Claim 3
Dependent Claim
18 words
A silver oxide primary cell as claimed in claim 1, wherein said chamfered edge is a bevelled face.
Claim 4
Dependent Claim
18 words
A silver oxide primary cell as claimed in claim 1, wherein said chamfered edge is a rounded edge.
Claim 5
Dependent Claim
31 words
A silver oxide primary cell as claimed n claim 1, wherein both of the opposed peripheral edges on the respective surfaces of the positive electrode are chamfered to provide chamfered edges.
Claim 6
Dependent Claim
18 words
A silver oxide primary cell as claimed in claim 4, wherein each chamfered edge is a bevelled face.
Claim 7
Dependent Claim
18 words
A silver oxide primary cell as claimed in claim 4, wherein each chamfered edge is a rounded edge.
Claim 8
Dependent Claim
49 words
A silver oxide primary cell as claimed in claim 1, wherein the area of the cup which is held in contact with the positive electrode is outwardly recessed to provide a seat for the positive electrode, said seat having a depth smaller than the thickness of the positive electrode.
Claim 9
Dependent Claim
19 words
A silver oxide primary cell as claimed in claim 1, wherein said silver oxide is a monovalent silver oxide.
Claim 10
Dependent Claim
19 words
A silver oxide primary cell as claimed in claim 1, wherein said silver oxide is a divalent silver oxide.
Claim 11
Dependent Claim
94 words
A silver oxide primary cell as claimed in claim 1, wherein the chamfered edge of the positive electrode is in the form of a bevel of an angle within the range of 10° to 30° and having a bevelled face of a length within the range of 1 to 3 mm, or in the form of a rounded edge of radius within the range of 0.2 to 0.4 mm, based on a positive electrode which is in the form of a disc having a diameter of 8 mm and a thickness of 0.9 mm.
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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) | 1981-10-16 | 1982-04-17 | 1982-10-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-10-16 | 1986-04-17 | 1986-10-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-10-16 | 1990-04-17 | 1990-10-17 | $7700.00 | Window Closed / Lapsed |