US4303604A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of making a high rate carbon cathode
Assignee: United States Department of the Army
•
Filing: 1980-04-14
•
Granted: 1981-12-01
•
Expires: 2000-04-14
Abstract
Abstract A high rate carbon cathode is made by mixing a carbon powder having a surface area of about 1000 square meters/gram with polytetrafluoroethylene and a sufficient amount of water to form a coherent mixture. The mixture is applied to an electrically conductive screen; the cathode formed while wet to an intermediate thickness, the cathode vacuum dried at about 100 degrees C., and the cathode cold compressed to obtain a final electrode porosity of greater than 80 percent. The cathode can be used in a lithium primary cell using a solution of an inorganic lithium salt in sulfuryl chloride as the electrolyte.
Inventors
- 👤 Sol Gilman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 18:30
CPC Classifications
H; H01; H01M; H01M4/00; H01M4/86; H01M4/96; Y; Y02; Y02E; Y02E60/00; Y02E60/30; Y02E60/50
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
97 words
Method of making a high rate carbon cathode for use in lithium-sulfuryl chloride battery cells, said method including the steps of: (A) mixing a carbon powder having a surface area of about 1000 square meters/gram with polytetrafluoroethylene and a sufficient amount of water to form a coherent mixture; (B) applying the mixture to an electrically conductive screen, (C) forming the cathode while wet to an intermediate thickness; (D) vacuum drying the cathode at a temperature of about 100 degrees C.; and (E) cold compressing the cathode to obtain a final electrode porosity of greater than 80 percent.
Claim 2
Dependent Claim
97 words
Method of making a high rate carbon cathode for use in lithium-sulfuryl chloride battery cells, said method including the steps of: (A) mixing a carbon powder having a surface area of about 1000 square meters/gram with polytetrafluoroethylene and a sufficient amount of water to form a coherent mixture; (B) applying the mixture to an electrically conductive screen, (C) forming the cathode while wet to an intermediate thickness; (D) vacuum drying the cathode at a temperature of about 100 degrees C.; and (E) cold compressing the cathode to obtain a final electrode porosity of greater than 80 percent.
Claim 3
Dependent Claim
26 words
Method according to claim 1 wherein in Step (A) the polytetrafluoroethylene is about 7 to 14 weight percent on a dry basis of the coherent mixture.
Claim 4
Dependent Claim
17 words
Method according to claim 1 wherein the electrically conductive screen is resistant to corrosion in sulfuryl chloride.
Claim 5
Dependent Claim
25 words
Method according to claim 3 wherein the electrically conductive screen is a nickel screen having a high tortuosity for good anchoring of the polytetrafluoroethylene-carbon mixture.
Claim 6
Dependent Claim
126 words
Method of making a high rate carbon cathode for use in lithium sulfuryl chloride battery cells, said method including the steps of: (A) mixing a carbon powder having a surface area of about 1000 square meters/gram with polytetrafluoroethylene and a sufficient amount of water to form a coherent mixture, the polytetrafluoroethylene being about 7 to 14 weight percent on a dry basis of the coherent mixture, (B) applying the mixture to a nickel screen having a high tortuosity for good anchoring of the polytetrafluoroethylene carbon mixture, (C) forming the cathode while wet to an intermediate thickness, (D) vacuum drying the cathode at a temperature of about 100 degrees C., and (E) cold compressing the cathode to obtain a final electrode porosity of greater than 80 percent.
Claim 7
Dependent Claim
126 words
Method of making a high rate carbon cathode for use in lithium sulfuryl chloride battery cells, said method including the steps of: (A) mixing a carbon powder having a surface area of about 1000 square meters/gram with polytetrafluoroethylene and a sufficient amount of water to form a coherent mixture, the polytetrafluoroethylene being about 7 to 14 weight percent on a dry basis of the coherent mixture, (B) applying the mixture to a nickel screen having a high tortuosity for good anchoring of the polytetrafluoroethylene carbon mixture, (C) forming the cathode while wet to an intermediate thickness, (D) vacuum drying the cathode at a temperature of about 100 degrees C., and (E) cold compressing the cathode to obtain a final electrode porosity of greater than 80 percent.
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) | 1984-11-30 | 1985-06-01 | 1985-12-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-11-30 | 1989-06-01 | 1989-12-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-11-30 | 1993-06-01 | 1993-12-01 | $7700.00 | Window Closed / Lapsed |