US3562634A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for determining the state of charge of nickel cadmium batteries by measuring the farad capacitance thereof
Assignee: United States Atomic Energy Commission
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Filing: 1968-12-16
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Granted: 1971-02-09
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Expires: 1988-12-16
Abstract
Abstract Method for predicting the capacity of nickel-cadmium batteries with a standard reference curve that indicates battery capacitance as a function of the state-of-charge of a given nickel-cadmium battery type wherein the standard reference curve is used with the measurement of the capacitance of any battery of the given type to indicate the state-of-charge of the battery.
Inventors
- 👤 Norman Latner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 15:25
CPC Classifications
G; G01; G01N; G01N27/00; G01N27/02; G01N27/22; G01N27/223; G01R; G01R31/00; G01R31/36; G01R31/378
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
51 words
The method of claim 1 for determining the state-of-charge of a nickel-cadmium battery wherein the batteries are initially discharged, fully charged, left standing for three hours, and then the farad capacitance thereof is measured whereby the measured capacitance indicates the state-of-charge of the battery with reference to the standard reference curve.
Claim 2
Dependent Claim
36 words
The method of claim 2 in which said initial discharging is down to 1.1 volts at a ten hour rate and is followed by charging that breaks down oxide on the cadmium electrode of said battery.
Claim 3
Dependent Claim
57 words
Method for measuring the capacity of nickel-cadmium batteries whose terminal voltage remains constant over a relatively wide range of charge, comprising the steps of nondestructively measuring the farad capacitance of said nickel-cadmium batteries substantially independently of contact and internal battery resistance and selectively determining from said capacitance measurement the state-of-chargE of said batteries without discharging the same.
Claim 4
Dependent Claim
39 words
The method claim 4 in which said measured farad capacitance is a function of the state-of-charge of said batteries corresponding to the curve of FIG. 3 for the use of said batteries as remote energy sources for balloon flights.
Claim 5
Dependent Claim
56 words
The method of claim 4 wherein said measured farad capacitance corresponds to the relationship of the farad capacitance to the state-of-charge of nickel-cadmium batteries of a single type selected from the group, consisting of button, cylindrical and button stack nickel-cadmium batteries, and said measurement of said farad capacitance is selectively made with batteries of that type.
Claim 6
Dependent Claim
39 words
The method of claim 4 wherein said farad capacitance of said batteries is measured with a 60 Hz four lead, transformer ratio arm bridge for measuring said capacitance substantially independently of the contact and internal resistance of said batteries.
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) | 1974-02-08 | 1974-08-10 | 1975-02-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-02-08 | 1978-08-10 | 1979-02-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-02-08 | 1982-08-10 | 1983-02-09 | $7700.00 | Window Closed / Lapsed |