US3790410A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for the manufacture of powdered tungsten carbide containing electrode material
Assignee: Siemens AG
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Filing: 1972-02-17
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Granted: 1974-02-05
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Expires: 1992-02-17
Abstract
Abstract Method of making electrode material containing tungsten carbide particles which comprises mixing tungsten carbide with a solid or liquid cokable organic substance. A solution of such organic substance may also be used. The organic substance in the mixture is precoked. The organic substance is subsequently coked at a temperature of 800* to 1,000* C.
Inventors
- 👤 K Mund
- 👤 G Richter
- 👤 M Wenzel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 08:59
CPC Classifications
H; H01; H01M; H01M4/00; H01M4/86; H01M4/90; H01M4/8663; H01M4/8673; H01M4/88; H01M4/8825; Y; Y02; Y02E; Y02E60/00; Y02E60/30; Y02E60/50
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
36 words
The method of claim 1, wherein the amount of organic substance added to the mixture is such that the final product contains 1 to 100 percent by weight of free carbon, based on the tungsten carbide.
Claim 2
Dependent Claim
16 words
The method of claim 2, wherein the added organic substance is a carbohydrate or a polymer.
Claim 3
Dependent Claim
48 words
The method of claim 3, wherein tungsten carbide is mixed with an aqueous solution of a carbohydrate; that the mixture is dried and the carbohydrate is precoked at a temperature of up to 300* C and is subsequently coked at about 900* C in a protective gas atmosphere.
Claim 4
Dependent Claim
54 words
The method of claim 1, wherein a chemical activating agent selected from the group consisting of magnesium chloride, zinc chloride, calcium chloride, potassium thiocyanate, potassium sulfide, sulfuric acid, phosphoric acid and alkali hydroxides is added to the mixture of tungsten carbide and the Organic substance to provide an increased porosity in the finished product.
Claim 5
Dependent Claim
15 words
The method of claim 5, wherein zinc chloride is used as the pore forming agent.
Claim 6
Dependent Claim
15 words
The method of claim 5, wherein magnesium chloride is used as the pore forming agent.
Claim 7
Dependent Claim
12 words
The method of claim 1 wherein said electrochemical cells are fuel cells.
Claim 8
Dependent Claim
25 words
The method of claim 1 wherein said tungsten carbide is mixed with said organic cokable substance with the latter in the form of a solid.
Claim 9
Dependent Claim
25 words
The method of claim 1 wherein said tungsten carbide is mixed with said organic cokable substance with the latter in the form of a liquid.
Claim 10
Dependent Claim
25 words
The method of claim 1 wherein said tungsten carbide is mixed with said organic cokable substance with the latter in the form of a solution.
Claim 11
Dependent Claim
18 words
The method of claim 1 wherein said organic substance is heated preferably to 900* C during said coking.
References Cited (Backward Citations)
GB213252A
Cited
US2083303A
Cited
US3297490A
Cited
US3248303A
Cited
US3413152A
Cited
DE2005395A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-02-04 | 1977-08-06 | 1978-02-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-02-04 | 1981-08-06 | 1982-02-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-02-04 | 1985-08-06 | 1986-02-05 | $7700.00 | Window Closed / Lapsed |