US4680241A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for restoring the lost capacity of nickel batteries and batteries formed thereby
Assignee: Nokia Bell Labs
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Filing: 1985-02-25
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Granted: 1987-07-14
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Expires: 2005-02-25
Abstract
Abstract A method for partially or fully restoring the lost capacities of nickel batteries, as well as the batteries produced by this method, is disclosed. In accordance with the inventive method, a nickel battery is cycled at least 10 times, with each cycle including a discharging step during which the capacity achieved at the end of the previous cycle is reduced by at least 5 percent, and a charging step. The charging rate employed during the charging step is greater than about C/10 per hour. Moreover, while the ratio of the amount of charge delivered to the battery during the charging step of each cycle to the amount of charge withdrawn from the battery during the previous cycle is greater than one, this ratio is chosen so that the temperature of the electrolyte of the battery does not exceed about 30 degrees Centigrade.
Inventors
- 👤 Christopher K. Dyer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 10:18
CPC Classifications
H; H01; H01M; H01M10/00; H01M10/42; H01M10/44; H02; H02J; H02J7/00; H02J7/90; H02J7/927; Y; Y02; Y02E; Y02E60/00; Y02E60/10
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
135 words
A method for making a battery which includes a nickel positive electrode, a negative electrode, and an electrolyte, said nickel positive electrode having an initial capacity less than a theoretical capacity, C, of said battery, comprising the step of cycling said battery at least 10 times, each cycle including both a discharging step during which the amount of charge withdrawn from the battery, q D , is greater than or equal to about 5 percent of the capacity achieved during the previous cycle, and a charging step in which the charging rate is greater than C/10 per hour, the amount of charge delivered to said battery during said charging step, q C , is greater than q D and is chosen so that a temperature of said electrolyte does not exceed about 30 degrees Centigrade.
Claim 2
Independent Claim
135 words
A method for making a battery which includes a nickel positive electrode, a negative electrode, and an electrolyte, said nickel positive electrode having an initial capacity less than a theoretical capacity, C, of said battery, comprising the step of cycling said battery at least 10 times, each cycle including both a discharging step during which the amount of charge withdrawn from the battery, q D , is greater than or equal to about 5 percent of the capacity achieved during the previous cycle, and a charging step in which the charging rate is greater than C/10 per hour, the amount of charge delivered to said battery during said charging step, q C , is greater than q D and is chosen so that a temperature of said electrolyte does not exceed about 30 degrees Centigrade.
Claim 3
Dependent Claim
23 words
The method of claim 1 wherein q is chosen so that said temperature of said electrolyte does not exceed about 10 degrees Centigrade.
Claim 4
Dependent Claim
25 words
The method of claim 1 wherein q D is greater than or equal to about 20 percent of the capacity achieved during the previous cycle.
Claim 5
Dependent Claim
16 words
The method of claim 1 wherein said charging rate is less than about 6C per hour.
Claim 6
Dependent Claim
20 words
The method of claim 1 wherein said charging rate ranges from about c/6 per hour to about 2C per hour.
Claim 7
Dependent Claim
27 words
The method of claim 1 wherein the ratio of q C to q D is greater than or equal to about 1.01 but less than about 1.6.
Claim 8
Dependent Claim
12 words
The method of claim 1 wherein said battery is a nickel-hydrogen battery.
Claim 9
Dependent Claim
12 words
The method of claim 1 wherein said battery is a nickel-cadmium battery.
Claim 10
Dependent Claim
12 words
The method of claim 1 wherein said battery is a nickel-zinc battery.
Claim 11
Dependent Claim
12 words
The method of claim 1 wherein said battery is a nickel-iron battery.
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) | 1990-07-13 | 1991-01-12 | 1991-07-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-07-13 | 1995-01-12 | 1995-07-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-07-13 | 1999-01-12 | 1999-07-14 | $7700.00 | Window Closed / Lapsed |