Patent US4836140A successfully refreshed from Google Patents.
Patent US5214385A successfully refreshed from Google Patents.
US5214385A
Expired / Lapsed
US
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Apparatus and method for utilizing polarization voltage to determine charge state of a battery
Assignee: Commonwealth Edison Co
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Filing: 1991-05-22
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Granted: 1993-05-25
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Expires: 2011-05-22
Abstract
Abstract An apparatus for measuring charge state of a battery having multiple cells includes a transmitter that is connected to the battery to apply a test signal across the battery. This test signal is preferably a continuous square wave signal having a frequency less than 3 Hz. The test signal alternates between a voltage adequate to charge the battery and a lower voltage, and the charging voltage is retained for a time sufficient to allow a polarization voltage to develop across individual cells. A receiver is connected to the cell to monitor the polarization voltage across a cell as it develops in response to the test signal. This polarization voltage can be monitored for example using a DC voltmeter, or by displaying the voltage versus time waveform. In either case an accurate indication of the state of the charge of the cell is provided.
Inventors
- 👤 Charles M. Gabriel
- 👤 Merlin E. Burkum
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 12:52
CPC Classifications
G; G01; G01R; G01R19/00; G01R19/165; G01R19/16533; G01R19/16538; G01R19/16542
Claims Analysis
Total Claims: 38
Claim 1
Independent Claim
118 words
An apparatus for measuring charge state of a battery comprising at least one cell which exhibits a polarization voltage when fully charged, said apparatus comprising: a transmitter connected to the battery and operative to apply a charging test signal to the cell when the cell is fully charged, said test signal characterized by at least one transition to a voltage value greater than the voltage of the cell to provide charging signal which is retained for a time sufficient to modify the polarization voltage when present across the cell; and a receiver connected to the cell and operative to monitor the polarization voltage across the cell to provide an indication of the state of charge of the cell.
Claim 2
Independent Claim
118 words
An apparatus for measuring charge state of a battery comprising at least one cell which exhibits a polarization voltage when fully charged, said apparatus comprising: a transmitter connected to the battery and operative to apply a charging test signal to the cell when the cell is fully charged, said test signal characterized by at least one transition to a voltage value greater than the voltage of the cell to provide charging signal which is retained for a time sufficient to modify the polarization voltage when present across the cell; and a receiver connected to the cell and operative to monitor the polarization voltage across the cell to provide an indication of the state of charge of the cell.
Claim 3
Dependent Claim
21 words
The apparatus of claim 1 wherein the test signal is repetitive and is characterized by a periodic series of the transitions.
Claim 4
Dependent Claim
21 words
The apparatus of claim 2 wherein the test signal comprises a square wave having a frequency less than about 3 Hz.
Claim 5
Dependent Claim
15 words
The apparatus of claim 3 wherein the frequency is no greater than about 1 Hz.
Claim 6
Independent Claim
28 words
The apparatus of claim i wherein the battery is connected to a battery charger and a load, and wherein the battery is being charged by the battery charger.
Claim 7
Dependent Claim
23 words
The apparatus of claim 1 wherein the receiver comprises a DC voltmeter, and wherein the indication comprises a measure of the polarization voltage.
Claim 8
Dependent Claim
44 words
The apparatus of claim 6 wherein the receiver further comprises: means for receiving a first voltage signal from the cell; and a filter operative to attenuate DC components of the first voltage signal and to supply a filtered voltage signal to the DC voltmeter.
Claim 9
Dependent Claim
22 words
The apparatus of claim 1 wherein the receiver comprises a display, and wherein the indication comprises a waveform of the polarization voltage.
Claim 10
Independent Claim
160 words
An apparatus for determining charge state of a battery comprising a first positive terminal and a first negative terminal, said battery comprising a cell comprising a second positive terminal and a second negative terminal, said battery connected to and being charged by a battery charger, said apparatus comprising: a. transmitter means connected to said first positive terminal and first negative terminal for applying thereto a square wave charging current signal at a selected frequency below about 3 Hz; b. receiver means connected to said second positive terminal and said second negative terminal for receiving a first voltage signal from said cell, said receiver means comprising: filter means for attenuating DC components of said first voltage signal and outputting a filtered second voltage signal; and measuring means connected to said filter means for measuring a characteristic of said second voltage signal, which varies with a polarization voltage of the cell to provide an indication of the charge state of said cell.
Claim 11
Independent Claim
160 words
An apparatus for determining charge state of a battery comprising a first positive terminal and a first negative terminal, said battery comprising a cell comprising a second positive terminal and a second negative terminal, said battery connected to and being charged by a battery charger, said apparatus comprising: a. transmitter means connected to said first positive terminal and first negative terminal for applying thereto a square wave charging current signal at a selected frequency below about 3 Hz; b. receiver means connected to said second positive terminal and said second negative terminal for receiving a first voltage signal from said cell, said receiver means comprising: filter means for attenuating DC components of said first voltage signal and outputting a filtered second voltage signal; and measuring means connected to said filter means for measuring a characteristic of said second voltage signal, which varies with a polarization voltage of the cell to provide an indication of the charge state of said cell.
Claim 12
Dependent Claim
13 words
The apparatus of claim 9 wherein said measuring means comprises a DC voltmeter.
Claim 13
Dependent Claim
26 words
The apparatus of claim 9 wherein said measuring means comprises a visual display means for displaying a voltage vs. time waveform of said second voltage signal.
Claim 14
Dependent Claim
17 words
The apparatus of claim 9 wherein said selected frequency is in the range of about 0.1-1.0 Hz.
Claim 15
Dependent Claim
22 words
The apparatus of claim 9 further comprising means for blocking current flow from said battery and battery charger to said transmitter means.
Claim 16
Dependent Claim
15 words
The apparatus of claim 9 wherein said battery is connected to an active electrical load.
Claim 17
Independent Claim
106 words
A method for determining charge state of a battery comprising at least one cell which exhibits a polarization voltage when fully charged, said method comprising the following steps: a. applying a charging test signal across the cell when the cell is fully charged, said test signal characterized by at least one transition to a voltage value greater than the voltage of the cell to provide a charging signal which is retained for a time sufficient to modify the polarization voltage when present across the cell; and b. monitoring the polarization voltage across the cell to provide an indication of the state of charge of the cell.
Claim 18
Independent Claim
106 words
A method for determining charge state of a battery comprising at least one cell which exhibits a polarization voltage when fully charged, said method comprising the following steps: a. applying a charging test signal across the cell when the cell is fully charged, said test signal characterized by at least one transition to a voltage value greater than the voltage of the cell to provide a charging signal which is retained for a time sufficient to modify the polarization voltage when present across the cell; and b. monitoring the polarization voltage across the cell to provide an indication of the state of charge of the cell.
Claim 19
Dependent Claim
18 words
The method of claim 15 wherein step (b) comprises the step of measuring magnitude of the polarization voltage.
Claim 20
Dependent Claim
21 words
The method of claim 15 wherein step (b) comprises the step of observing a waveform of the polarization voltage versus time.
Claim 21
Dependent Claim
68 words
The method of claim 15 comprising the following additional steps: c. discharging said cell after step (b); d. applying the test signal across the cell after the start of step (c); e. monitoring the polarization voltage across the cell after the start of step (d) to provide a second indication of the state of charge of the cell; and f. comparing the indications of steps (b) and (e).
Claim 22
Dependent Claim
55 words
The method of claim 16 comprising the following additional steps: c. discharging said cell after step (b); d. applying the test signal across the cell after the start of step (c); e. measuring the magnitude of the polarization voltage after the start of step (d); and f. comparing the magnitudes of steps (b) and (e).
Claim 23
Dependent Claim
57 words
The method of claim 17 comprising the following additional steps: c. discharging said cell after step (b); d. applying the test signal across the cell after the start of step (c); e. observing a waveform of the polarization voltage versus time after the start of step (d); and f. comparing the waveforms of steps (b) and (e).
Claim 24
Dependent Claim
21 words
The method of claim 15 wherein the test signal is repetitive and is characterized by a periodic series of the transitions.
Claim 25
Dependent Claim
21 words
The method of claim 21 wherein the test signal comprises a square wave having a frequency less than about 3 Hz.
Claim 26
Dependent Claim
15 words
The method of claim 22 wherein the frequency is no greater than about 1 Hz.
Claim 27
Independent Claim
154 words
A method for determining charge state of a battery comprising a first positive terminal and a first negative terminal, said battery comprising a cell comprising a second positive terminal and a second negative terminal, said battery connected to and being charged by a battery charger, said method comprising the following steps: a. applying a square wave charging current signal at a selected frequency less than about 3 Hz to said first positive terminal and said first negative terminal; b. obtaining a first voltage signal indicative of cell voltage between said second positive terminal and said second negative terminal; c. passing said first voltage signal through a filter, said filter selected to attenuate DC components of said first voltage signal and to output a filtered second voltage signal; and d. measuring a characteristic of said second voltage signal which varies with a polarization voltage of the cell to determine the charge state of said cell.
Claim 28
Independent Claim
154 words
A method for determining charge state of a battery comprising a first positive terminal and a first negative terminal, said battery comprising a cell comprising a second positive terminal and a second negative terminal, said battery connected to and being charged by a battery charger, said method comprising the following steps: a. applying a square wave charging current signal at a selected frequency less than about 3 Hz to said first positive terminal and said first negative terminal; b. obtaining a first voltage signal indicative of cell voltage between said second positive terminal and said second negative terminal; c. passing said first voltage signal through a filter, said filter selected to attenuate DC components of said first voltage signal and to output a filtered second voltage signal; and d. measuring a characteristic of said second voltage signal which varies with a polarization voltage of the cell to determine the charge state of said cell.
Claim 29
Dependent Claim
25 words
The method of claim 24 wherein said characteristic of said second voltage signal is measured by observing a first peak-to-peak voltage on a DC voltmeter.
Claim 30
Dependent Claim
22 words
The method of claim 25 comprising the additional step of comparing said first peak-to-peak voltage to a pre-set standard for said battery.
Claim 31
Dependent Claim
22 words
The method of claim 24 wherein said characteristic of said second voltage signal is measured as a first voltage vs. time waveform.
Claim 32
Dependent Claim
24 words
The method of claim 27 comprising the additional step of comparing said first voltage vs. time waveform to a known waveform indicating full charge.
Claim 33
Dependent Claim
38 words
The method of claim 25 comprising the additional steps of discharging said cell using a discharge resistor; measuring a second peak-to-peak voltage of said cell following discharge; and comparing said first peak-to-peak voltage to said second peak-to-peak voltage.
Claim 34
Dependent Claim
80 words
The method of claim 29 wherein the comparing step comprises the step of determining a ratio of said first peak-to-peak voltage to said second peak-to-peak voltage, and wherein the method comprises the additional step of comparing said ratio of peak-to-peak voltages to a pre-set standard for said battery; wherein if said ratio exceeds a first preselected value said cell is classified as fully charged and if said ratio is below a second preselected value said cell is classified as shorted.
Claim 35
Dependent Claim
49 words
The method of claim 27 comprising the additional steps of discharging said cell using a discharge resistor; observing a second voltage vs. time waveform of said cell following discharge; and observing whether said first voltage vs. time waveform collapses following discharge to determine the charge state of said cell.
Claim 36
Dependent Claim
16 words
The method of claim 24 wherein said selected frequency is in the range of 0.1-1.0 Hz.
Claim 37
Dependent Claim
16 words
The method of claim 25 wherein said selected frequency is in the range of 0.1-1.0 Hz.
Claim 38
Dependent Claim
16 words
The method of claim 26 wherein said selected frequency is in the range of 0.1-1.0 Hz.
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 7.5 Years (Year 8) | 2000-05-24 | 2000-11-23 | 2001-05-25 | $3760.00 | Window Closed / Lapsed |
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