US3697822A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrolytic capacitor having an electrode with a metallized cracked oxide surface
Assignee: Sprague Electric Co
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Filing: 1971-07-21
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Granted: 1972-10-10
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Expires: 1991-07-21
Abstract
Abstract An aluminum surface is treated with hot water to produce a hydrous aluminum oxide film. The film is then heated treated so as to crack the oxide film. A thin film of aluminum is then deposited over this skeletal structure, and the resulting thin film contacts the original aluminum surface through the cracks in the oxide film. A high surface area electrode that is economical to manufacture is obtained in this fashion.
Inventors
- 👤 Robert S Alwitt
- 👤 Robert W Santway
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 05:22
CPC Classifications
H; H01; H01G; H01G9/00; H01G9/004; H01G9/04; H01G9/048
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
12 words
The electrolytic capacitor of claim 1 wherein said metallized layer is aluminum.
Claim 2
Dependent Claim
16 words
The electrolytic capacitor of claim 1 wherein said at least one electrode is said cathode electrode.
Claim 3
Dependent Claim
52 words
The electrolytic capacitor of claim 3 wherein said formed anode electrode includes an aluminum substrate having a cracked oxide film thereon, an outer metallized layer of at least one metal taken from the group consisting of aluminum and tantalum in direct contact with said aluminum substrate, and an anodized layer formed thereon.
Claim 4
Dependent Claim
12 words
The electrolytic capacitor of claim 4 wherein said metallized layer is aluminum.
Claim 5
Dependent Claim
47 words
An electrode for an electrolytic capacitor comprising an aluminum substrate having a cracked oxide film thereon, and an outer metallized layer of at least one metal taken from the group consisting of aluminum and tantalum in direct contact with said aluminum substrate through said cracked oxide film.
Claim 6
Dependent Claim
16 words
The electrode of claim 6 wherein said outer metallized layer has an anodized layer formed thereon.
Claim 7
Dependent Claim
11 words
The electrode of claim 6 wherein said metallized layer is aluminum.
Claim 8
Dependent Claim
99 words
A process for making an electrode for an electrolytic capacitor comprising: a. reacting a surface of an aluminum substrate with hot water so as to produce a hydrous oxide film thereon; b. heating said hydrous oxide film at a temperature of between 400*-650* C so as to crack said Oxide film; c. depositing a film of at least one metal selected from the group consisting of aluminum and tantalum on said cracked oxide film so as to directly contact said aluminum substrate through said cracked oxide film; said metal film ranging in thickness from 500 A to 10,000 A.
Claim 9
Dependent Claim
12 words
The process of claim 9 wherein said deposited metal film is anodized.
Claim 10
Dependent Claim
22 words
The process of claim 10 wherein said hydrous oxide film is heated at 450* C, and said deposited metal film is aluminum.
Claim 11
Dependent Claim
22 words
The process of claim 9 wherein said hydrous oxide film is heated at 450* C; and said deposited metal film is aluminum.
Claim 12
Dependent Claim
14 words
The process of claim 12 wherein said metal film is deposited by vacuum deposition.
Claim 13
Dependent Claim
155 words
A process for making an electrolytic capacitor comprising: a. providing a formed valve metal anode electrode and a cathode contact electrode; b. reacting a surface of an aluminum substrate of at least one of said electrodes with hot water so as to produce a hydrous oxide film thereon; c. heating said hydrous oxide film at a temperature of between 400*-650* C so as to crack said oxide film; d. depositing a film of at least one metal selected from the group consisting of aluminum and tantalum on said cracked oxide film so as to directly contact said aluminum substrate through said cracked oxide film, and said metal film ranging in thickness from 500 A to 10,000 A, thereby increasing the surface area thereof for at least one of said electrodes; e. assembling said at least one electrode and the other electrode spaced from each other, and an electrolyte in contact with both of said electrodes.
Claim 14
Dependent Claim
15 words
The process of claim 14 wherein said at least one electrode is said cathode electrode.
Claim 15
Dependent Claim
22 words
The process of claim 15 wherein said hydrous oxide film is heated at 450* C, and said deposited metal film is aluminum.
Claim 16
Dependent Claim
11 words
The process of claim 14 wherein said deposited metal is anodized.
Claim 17
Dependent Claim
22 words
The process of claim 14 wherein said hydrous oxide film is heated at 450* C; and said deposited metal film is aluminum.
Claim 18
Dependent Claim
14 words
The process of claim 18 wherein said metal film is deposited by vacuum deposition.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-10-10 | 1976-04-10 | 1976-10-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-10-10 | 1980-04-10 | 1980-10-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-10-10 | 1984-04-10 | 1984-10-10 | $7700.00 | Window Closed / Lapsed |