US3894887A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hydrogen-bromine secondary battery
Assignee: California Institute of Technology
•
Filing: 1973-07-11
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Granted: 1975-07-15
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Expires: 1993-07-11
Abstract
Abstract A secondary battery utilizing hydrogen and halogen as primary reactants comprises inert anode and cathode initially contacting an aqueous solution of an acid and an alkali metal bromide. The hydrogen generated during charging of the cell is stored as gas, while the bromine becomes dissolved predominantly in the lower layers of the acid electrolyte. Preferred components comprise phosphoric acid and lithium bromide.
Inventors
- 👤 Christopher England
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 16:23
CPC Classifications
H; H01; H01M; H01M10/00; H01M10/36; Y; Y02; Y02E; Y02E60/00; Y02E60/10
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
105 words
A SECONDARY ELECTRICAL CELL COMPRISING A BODY OF AQUEOUS ELECTROLYTE WHICH, IN UNCHARGED CONDITION OF THE CELL, CONSISTS ESSENTIALLY OF ACID FROM THE GROUP CONSISTING OF PHOSPHORIC AND SULFURIC ACIDS, AND ALKALI METAL BROMIDE FROM THE GROUP CONSISTING OF LITHIUM, SODIUM AND POTASSIUM BROMIDES, THE RELATIVE ACID AND BROMIDE CONCENTRATIONS BEING SUCH THAT THE ATOMIC RATIO OF HYDROGEN TO BROMINE IS AT LEAST ABOUT UNITY, ANODE AND CATHODE STRUCTURES FORMED OF ELECTRICALLY CONDUCTIVE AND CHEMICALLY INERT MATERIALS CONTACTING THE ELECTROLYTE WITH THE ANODE SPACED ABOVE THE CATHODE, AND HOUSING STRUCTURE FOR THE ELECTROLYTE INCLUDING MEANS FOR CONTAINING HYDROGEN PRODUCED DURING THE CHANGING OF THE CELL.
Claim 2
Dependent Claim
105 words
A SECONDARY ELECTRICAL CELL COMPRISING A BODY OF AQUEOUS ELECTROLYTE WHICH, IN UNCHARGED CONDITION OF THE CELL, CONSISTS ESSENTIALLY OF ACID FROM THE GROUP CONSISTING OF PHOSPHORIC AND SULFURIC ACIDS, AND ALKALI METAL BROMIDE FROM THE GROUP CONSISTING OF LITHIUM, SODIUM AND POTASSIUM BROMIDES, THE RELATIVE ACID AND BROMIDE CONCENTRATIONS BEING SUCH THAT THE ATOMIC RATIO OF HYDROGEN TO BROMINE IS AT LEAST ABOUT UNITY, ANODE AND CATHODE STRUCTURES FORMED OF ELECTRICALLY CONDUCTIVE AND CHEMICALLY INERT MATERIALS CONTACTING THE ELECTROLYTE WITH THE ANODE SPACED ABOVE THE CATHODE, AND HOUSING STRUCTURE FOR THE ELECTROLYTE INCLUDING MEANS FOR CONTAINING HYDROGEN PRODUCED DURING THE CHANGING OF THE CELL.
Claim 3
Dependent Claim
57 words
A secondary cell according to claim 1 in which, in uncharged condition of the cell, said acid is present in the electrolyte in approximately the concentration producing maximum electrical conductivity, and said bromide is present in the electrolyte in such concentration that the atomic ratio of hydrogen to bromine exceeds unity by at least about 3 percent.
Claim 4
Dependent Claim
53 words
A secondary cell according to claim 1 in which said body of electrolyte has a free surface within said housing means, said cathode structure contacts the electrolyte body predominantly in the lower portion thereof and said anode structure contacts the electrolyte body predominantly in the upper portion thereof and adjacent the free surface.
Claim 5
Dependent Claim
34 words
A secondary cell according to claim 3 including a generally horizontal separator permeable to the electrolyte and mounted between the anode and cathode structures and dividing said body of electrolyte into said two portions.
Claim 6
Dependent Claim
20 words
A secondary cell according to claim 1 in which said acid is phosphoric acid and said bromide is lithium bromide.
References Cited (Backward Citations)
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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) | 1978-07-14 | 1979-01-13 | 1979-07-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-07-14 | 1983-01-13 | 1983-07-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-07-14 | 1987-01-13 | 1987-07-15 | $7700.00 | Window Closed / Lapsed |