Consumer battery having a built-in indicator

• US 6,483,275 B1
• Filed: 04/23/1999
• Issued: 11/19/2002
• Est. Priority Date: 04/23/1999
• Status: Expired due to Fees

• Current Assignee: Board of Trustees of The University of Illinois
• Original Assignee: Board of Trustees of The University of Illinois
• Inventors: Gartstein, Vladimir, Nebrigic, Dragan Danilo
• Primary Examiner(s): TOATLEY, GREGORY J
• Application Number:
  US09/298,804
• Time in Patent Office: 1,306 Days
• Field of Search: 320/107, 320/112, 320/135, 320/136, 324/426, 324/427, 324/433, 429/90, 429/91, 429/92, 429/93, 340/636
• US Class Current: 320/135
• CPC Class Codes: G01R 31/3648 comprising digital calculation means, e.g. for performing an algorithm
• CPC Class Codes: G01R 31/3835 involving only voltage measurements
• CPC Class Codes: H01M 10/4257 Smart batteries, e.g. electronic circuits inside the housing of the cells or batteries
• CPC Class Codes: H01M 10/48 Accumulators combined with arrangements for measuring, testing or indicating the condition of cells, e.g. the level or density of the electrolyte constructional details of current conducting connections for detecting conditions inside cells or batteries, e.g. details of voltage sensing terminals, H01M50/569
• CPC Class Codes: H01M 10/488 Cells or batteries combined with indicating means for external visualization of the condition, e.g. by change of colour or of light density
• CPC Class Codes: H01M 6/5044 Cells or batteries structurally combined with cell condition indicating means
• CPC Class Codes: H02J 2207/20 Charging or discharging characterised by the power electronics converter
• CPC Class Codes: H02J 9/061 for DC powered loads
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

A built-in battery integrated circuit (50) in the form of a flexible circuit board (70) of a consumer battery (10) senses a voltaic cell electrode (32″, 34″) voltage, and when the voltage is indicative of a low state of charge, activates an indicating system (11), alerting a user to the impending battery failure. In addition, a tester actuator button (15) is placed exteriorly on the battery container (12) to manually activate the indicating system (11) to verify that the battery has not become so low of charge as to prevent the indicating system from functioning. Advantageously, the tester actuator button (15) may further enable the built-in battery integrated circuit, thus having all internal electronics unpowered until a user decides to use the battery (10). The indicating system (11) includes an analog indicator such as a bargraph and/or a pulse indicator (64) such as an LED or LCD.

Claims

1. A battery comprising:

a primary voltaic cell including a positive electrode and a negative electrode, said primary voltaic cell storing electrical charge resulting in an electrode voltage across said positive and said negative electrodes;

an indicating system including an indicator and an indicator controller, said indicator controller interposed between said electrodes and said indicator, said indicator controller responsive to said electrode voltage for controlling said indicator;

a container substantially enclosing said primary voltaic cell and said indicating system; and

,

wherein said indicator controller includes a voltage threshold detector electrically coupled to said electrodes, said voltage threshold detector responsive to said electrode voltage declining to a voltage threshold whereupon said voltage threshold detector activates said indicating system to thereby activate said indicator.

2. The battery of claim 1 wherein said indicating system includes a voltage reference and wherein said voltage threshold detector includes a trigger coupled to said electrodes and coupled to said voltage reference.

3. The battery of claim 1 wherein said voltage threshold detector comprises a differential-input hysteretic Schmitt trigger having a first and a second input and a trigger output, said first input electrically coupled to said electrode voltage and said second input electrically coupled to a voltage divider biased by said voltage reference, said voltage divider generating a predetermined voltage threshold, said output controlling battery power to the remaining portion of said indicating system.

4. The battery of claim 1 wherein said indicator controller further includes a slow pulse oscillator electrically enabled by said voltage threshold detector and controlling said indicator.

5. The battery of claim 4 wherein said indicator includes a pulse indicator.

6. The battery of claim 5 wherein said pulse indicator comprises one of a Light Emitting Diode and a Liquid Crystal Display.

7. The battery of claim 1 further including a reserve switch and a reserve voltaic cell substantially enclosed by said container, said reserve switch interposed between said primary voltaic cell and said reserve voltaic cell and controlled by said indicating system to selectively augment the electrical charge of said primary voltaic cell.

8. The battery of claim 7 wherein said reserve voltaic cell includes a positive electrode and a negative electrode, said reserve negative electrode electrically coupled to said primary negative electrode, and wherein said reserve switch switchably connects said primary positive electrode and said reserve positive electrode to said indicating system.

9. The battery of claim 1 wherein said indicating system further includes a positive conductor, a negative conductor, and a grounding strap, and wherein said indicator controller comprises a flexible circuit board, said positive conductor electrically coupled with said positive electrode of said primary voltaic cell and said negative conductor electrically coupled with said negative electrode of said primary voltaic cell, said flexible circuit board electrically coupled to said positive conductor and to said grounding strap, said grounding strap electrically coupled to said negative conductor, wherein said indicator is exteriorly placed on said container, said container further including a positive terminal and a negative terminal, said flexible circuit board electrically coupled to said positive terminal, and said negative terminal electrically coupled to said negative electrode, negative conductor, and said ground strap;

wherein an artificial load resistor is provided on said flexible circuit board to provide a representative measurement of said electrode voltage for determining said voltaic cell storage charge.

10. The battery of claim 9 wherein said positive terminal comprises a top cap sized and configured to enclose a portion of said flexible circuit board.

11. The battery of claim 1 further including a tester actuator exteriorly placed of said container, said tester actuator responsive to manual input for electrically coupling said electrodes of said primary voltaic cell to a first end of a test resistor having a second end electrically coupled to said negative electrode, said tester actuator further responsive to manual input for activating said indicator.

12. The battery of claim 11 wherein said tester actuator switchably couples said positive electrode to said indicator in response to manual input for activating said indicator.

13. The battery of claim 11 wherein said indicator includes a bargraph indicator.

14. The battery of claim of claim 11 wherein said container further includes a positive terminal electrically coupled to said indicating system and a negative terminal electrically coupled to said negative electrode, said battery further including a latch electrically interposed between said electrodes and said terminals and closably responsive to said tester actuator.

15. The battery of claim 14 wherein said latch comprises a one-shot multivibrator.

16. The battery of claim 1 further including a positive terminal and a negative terminal and wherein said indicating system includes a power converter electrically interposed between said electrodes and said terminals for converting the electrode voltage at said electrodes to a terminal voltage at said terminals, said battery further including a latch electrically interposed between said electrodes and said terminals and closably responsive to said tester actuator wherein said electrode voltage is increased in response to detecting said electrode voltage declining below a threshold level.

17. The battery of claim 16 wherein said power converter includes a power control state machine with stop-step oscillator for selectively increasing the terminal voltage in response to the electrode voltage declining to a threshold.

18. A battery as in claim 1 further comprising:

an indicating system comprising an indicator and an indicator controller, said indicator controller measuring voltage across said positive and said negative electrodes when said battery is connected to an external load.

19. A battery as in claim 1 further comprising:

an indicating system comprising an indicator and an indicator controller, said indicator controller measuring voltage across said positive and said negative electrodes using an internal artificial load.

20. A battery having a predetermined outer dimension substantially equal to a consumer battery and a terminal voltage, the battery comprising:

a primary voltaic cell including a positive electrode and a negative electrode, said primary voltaic cell storing electrical charge resulting in an electrode voltage across said positive and said negative electrodes;

an indicating system including an indicator and an indicator controller, said indicator controller interposed between said electrodes and said indicator, said indicator controller responsive to said electrode voltage for controller said indicator; and

,

a container substantially enclosing said primary voltaic cell and said indicating system, said container conforming to the predetermined outer dimensions of the consumer battery, said container including a positive terminal and a negative terminal providing the terminal voltage.

21. A method for indicating with a built-in integrated circuit a state of charge of a battery having a voltaic cell, the method including:

detecting with said built-in integrated circuit an electrode voltage of said voltaic cell indicative of a state of charge of said voltaic cell;

comparing said electrode voltage to a reference voltage;

indicating the state of charge of said voltaic cell in response to said electrode voltage declining below the reference voltage;

measuring an electrode voltage of said voltaic cell while connected to an outside load; and

,

measuring an electrode voltage of said voltaic cell when it is connected to an internal artificial load.

22. The method of claim 21 further including:

boosting the electrode voltage in response to detecting the electrode voltage declining below a threshold.

23. A battery comprising:

a primary voltaic cell including a positive electrode and a negative electrode, the cell storing electrical charge resulting in an electrode voltage across the positive and negative electrodes;

a power sensing circuit operatively connected across the positive and negative electrodes to sense the electrode voltage, said circuit generating a conditioned voltage representative of the stored electrical charge;

a battery container enclosing the voltaic cell and the power sensing circuit, the container including an indicator operatively coupled to the power sensing circuit for generating an indication exterior to the container in response to the conditioned voltage; and

,

wherein said indicator controller includes a voltage threshold detector electrically coupled to said electrodes, said voltage threshold detector responsive to said electrode voltage declining to a voltage threshold whereupon said voltage threshold detector activates said indicating system to thereby activate said indicator.

24. A battery as in claim 23 further comprising:

an internal artificial load connected across said positive and said negative electrodes to generate an electrode voltage representative of said stored electrical charge.

25. A consumer battery having a standard outer dimension and standard nominal terminal voltage, the consumer battery comprising:

a voltaic cell including a positive electrode and a negative electrode, the voltaic cell storing electrical charge resulting in an electrode voltage across the positive and negative electrodes;

a battery container enclosing the voltaic cell and including a positive terminal and a negative terminal;

a latch configured to electrically couple said electrodes to said terminals; and

an actuator exteriorly placed in said battery container and operably coupled to said latch to command said latch to close in response to manual activation by a user.

26. The consumer battery of claim 25 wherein said latch comprises a one-shot latch remaining closed after first actuation.

27. A battery comprising:

a voltaic cell including a positive electrode and a negative electrode, said voltaic cell storing electrical charge resulting in an electrode voltage across said positive and said negative electrodes;

an indicating system including a pulse indicator and an indicator controller, said indicator controller interposed between said electrodes and said pulse indicator, said indicator controller responsive to said electrode voltage for controlling said pulse indicator with a pulse rate indicative of the state of charge of the voltaic cell; and

a container substantially encompassing said voltaic cell and said indicating system.

28. A battery comprising:

a primary voltaic cell including a positive electrode and a negative electrode, the cell storing electrical charge resulting in an electrode voltage across the positive and negative electrodes;

a battery container enclosing the voltaic cell, the container including a positive terminal and a negative terminal; and

a power converter within the container, said power converter electrically coupled between said electrodes and said terminals for boosting the electrode voltage to a terminal voltage across said terminals, the power converter including a first switch electrically coupled across said electrodes, a second switch electrically coupled to said positive electrode and said positive terminal, and a power control state machine with stop-step oscillator operatively coupled to said first switch and said second switch.