US5519303A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fast battery charging method and apparatus with temperature gradient detection
Assignee: Motorola Solutions Inc
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Filing: 1993-09-30
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Granted: 1996-05-21
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Expires: 2013-09-30
Abstract
Abstract A control circuit and method of operating a battery charging system are provided capable of disabling charging of a rechargeable battery (320) based upon a second derivative (410) of a temperature of the battery. A thermistor (330), contained in a rechargeable battery pack together with the rechargeable battery (320), detects the temperature of the battery. Charging of the battery can be disabled when the second derivative (410) of the temperature of the battery is positive and the first derivative (390) of the temperature of the battery is higher than a predetermined threshold.
Inventors
- 👤 Terrance J. Goedken
- 👤 Daniel J. Theobald
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 04:40
CPC Classifications
H; H02; H02J; H02J7/00; H02J7/90; H02J7/971; H02J7/975; H02J7/40; H02J7/443; H01; H01M; H01M10/00; H01M10/42; H01M10/44; H02J7/485; H02J7/70; H02J7/751; H02J7/977; Y; Y02; Y02E; Y02E60/00; Y02E60/10
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
104 words
A control circuit for charging a battery, comprising: a temperature sensor for sensing a temperature of the battery; a first derivative calculating means for calculating a first derivative of the temperature of the battery; a second derivative calculating means for calculating a second derivative of the temperature of the battery; and a switch operatively coupled to said temperature sensor, said first derivative calculating means and said second derivative calculating means for disabling charging of the battery when both the second derivative of the temperature of the battery is positive and the first derivative of the temperature of the battery is above a predetermined threshold.
Claim 2
Dependent Claim
104 words
A control circuit for charging a battery, comprising: a temperature sensor for sensing a temperature of the battery; a first derivative calculating means for calculating a first derivative of the temperature of the battery; a second derivative calculating means for calculating a second derivative of the temperature of the battery; and a switch operatively coupled to said temperature sensor, said first derivative calculating means and said second derivative calculating means for disabling charging of the battery when both the second derivative of the temperature of the battery is positive and the first derivative of the temperature of the battery is above a predetermined threshold.
Claim 3
Dependent Claim
22 words
A control circuit for charging a battery according to claim 1, wherein said temperature sensor includes a pair of contacts coupled thereto.
Claim 4
Dependent Claim
18 words
A control circuit for charging a battery according to claim 1, wherein said temperature sensor comprises a thermistor.
Claim 5
Dependent Claim
110 words
A battery charger for charging a battery pack, comprising: a plurality of contacts for mating with the battery pack, at least a pair of said contacts providing a temperature signal indicative of a temperature of the battery pack; a derivative calculating circuit operatively coupled to said pair of contacts to receive the temperature signal for calculating derivatives of the temperature of the battery pack; and a switch operatively connected to said derivative calculating circuit to disable charging of the battery pack when both a second derivative of the temperature of the battery pack is positive and a derivative of the temperature of the battery pack is above a predetermined threshold.
Claim 6
Dependent Claim
110 words
A battery charger for charging a battery pack, comprising: a plurality of contacts for mating with the battery pack, at least a pair of said contacts providing a temperature signal indicative of a temperature of the battery pack; a derivative calculating circuit operatively coupled to said pair of contacts to receive the temperature signal for calculating derivatives of the temperature of the battery pack; and a switch operatively connected to said derivative calculating circuit to disable charging of the battery pack when both a second derivative of the temperature of the battery pack is positive and a derivative of the temperature of the battery pack is above a predetermined threshold.
Claim 7
Dependent Claim
31 words
A battery charger according to claim 4 further comprising a charger base having at least one receptacle for holding the battery pack with said contacts of the charger base coupled thereto.
Claim 8
Dependent Claim
86 words
A battery charging system, comprising: a rechargeable cell having a temperature sensor configured to sense a temperature of the rechargeable cell; a derivative calculating circuit connectable to said rechargeable cell for calculating derivatives of the temperature of the rechargeable cell; and a switch operatively connected to said derivative calculating circuit to disable charging of the rechargeable cell when both a second derivative of the temperature of the rechargeable cell is positive and a derivative of the temperature of the rechargeable cell is above a predetermined threshold.
Claim 9
Dependent Claim
86 words
A battery charging system, comprising: a rechargeable cell having a temperature sensor configured to sense a temperature of the rechargeable cell; a derivative calculating circuit connectable to said rechargeable cell for calculating derivatives of the temperature of the rechargeable cell; and a switch operatively connected to said derivative calculating circuit to disable charging of the rechargeable cell when both a second derivative of the temperature of the rechargeable cell is positive and a derivative of the temperature of the rechargeable cell is above a predetermined threshold.
Claim 10
Independent Claim
71 words
A method of charging a battery, comprising: (a) sensing a temperature of the battery; (b) calculating a first derivative of the temperature of the battery; (c) calculating a second derivative of the temperature of the battery; and (d) disabling charging of the battery when both the second derivative of the temperature of the battery is positive and the first derivative of the temperature of the battery is above a predetermined threshold.
Claim 11
Independent Claim
71 words
A method of charging a battery, comprising: (a) sensing a temperature of the battery; (b) calculating a first derivative of the temperature of the battery; (c) calculating a second derivative of the temperature of the battery; and (d) disabling charging of the battery when both the second derivative of the temperature of the battery is positive and the first derivative of the temperature of the battery is above a predetermined threshold.
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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) | 1999-05-21 | 1999-11-20 | 2000-05-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-05-21 | 2003-11-20 | 2004-05-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-05-21 | 2007-11-20 | 2008-05-21 | $7700.00 | Window Closed / Lapsed |