DETECTING AN OPEN WIRE BETWEEN A BATTERY CELL AND AN EXTERNAL CIRCUIT

• US 20130041606A1
• Filed: 08/10/2011
• Published: 02/14/2013
• Est. Priority Date: 08/10/2011
• Status: Abandoned Application

• Current Assignee: O2 Micro International Limited (O2 Micro Incorporated)
• Original Assignee: Guoxing Li, Xiaohu Tang
• Inventors: TANG, Xiaohu, LI, Guoxing
• Application Number:
  US13/207,255
• Publication Number:
  US 20130041606A1
• Time in Patent Office: Days
• US Class Current: 702/63
• CPC Class Codes: G01R 31/396 Acquisition or processing of data for testing or for monitoring individual cells or groups of cells within a battery
• CPC Class Codes: G01R 31/52 Testing for short-circuits, leakage current or ground faults
• CPC Class Codes: G01R 31/54 Testing for continuity

Abstract

A device for detecting an open wire coupled to a battery includes a first pin and a second pin. The first pin is coupled to a positive terminal of a battery cell through a connection circuit. The second pin is coupled to a negative terminal of the battery cell through the connection circuit. A path of a current through the connection circuit changes in response to a wire between the connection circuit and the battery cell becoming open, and a change in a detecting voltage across the first pin and the second pin indicates a change in the path.

Claims

1. A device for detecting an open wire coupled to a battery, said device comprising:

a first pin coupled to a positive terminal of a battery cell through a connection circuit; and

a second pin coupled to a negative terminal of said battery cell through said connection circuit, wherein a path of a current through said connection circuit changes in response to a wire between said connection circuit and said battery cell becoming open, and wherein a change in a detecting voltage across said first pin and said second pin indicates a change in said path.

2. The device of claim 1, wherein said connection circuit comprises a capacitor coupled in parallel with said battery cell.

3. The device of claim 1, further comprising a selector coupled to said connection circuit via said first pin and said second pin, wherein said selector selects said battery cell from a plurality of battery cells in said battery.

4. The device of claim 1, further comprising an amplifier coupled to said selector to amplify said detecting voltage.

5. The device of claim 1, further comprising an ND converter coupled to said connection circuit that outputs a voltage reading based on said detecting voltage and that converts said voltage reading from analog to digital.

6. The device of claim 1, further comprising a micro control unit (MCU) that compares said detecting voltage with a range, wherein said wire is indicated as being open if said detecting voltage is outside said range.

7. The device of claim 1, further comprising a memory for storing a voltage reading that is based on said detecting voltage, wherein said memory further comprises a flag register for storing a status flag that indicates whether said wire is open.

8. The device of claim 1, further comprising an open-wire detection module coupled to said connection circuit and operable for generating said current.

9. A circuit for detecting open wires coupled to a plurality of battery cells, said circuit comprising:

a selector coupled to said plurality of battery cells and operable for selecting a target battery cell from said battery cells;

an open-wire detection module coupled to said selector and operable for generating a current;

a connection circuit including a plurality of wires coupled between said battery cells and said selector and providing a plurality of paths for said current based on states of said wires, wherein said connection circuit further generates a detecting voltage that is based on a path of said current through said connection circuit; and

a micro control unit (MCU) coupled to said open-wire detection module and said selector and operable for determining an state of a wire based on said detecting voltage.

10. The circuit of claim 9, wherein said connection circuit comprises a capacitor coupled in parallel with said battery cell.

11. The circuit of claim 9, wherein said selector comprises a plurality of first switches and a plurality of second switches.

12. The circuit of claim 9, further comprising an amplifier coupled to said selector to amplify said detecting voltage.

13. The circuit of claim 12, further comprising an ND converter coupled to said amplifier that outputs a voltage reading based on said detecting voltage and converts said voltage reading from analog to digital.

14. The circuit of claim 9, wherein said MCU further comprises a memory for storing a voltage reading based on said detecting voltage.

15. The circuit of claim 9, wherein said MCU comprises a flag register for storing status flags that indicate said states of said wires.

16. The circuit of claim 9, wherein said open-wire detection module comprises a current source and a current sink.

17. A method for detecting open wires coupled to a plurality of battery cells, said method comprising:

selecting a target battery cell from said battery cells;

generating a current through a connection circuit connected to said target battery cell;

measuring a detecting voltage that is based on a path of said current through said connection circuit;

indicating a change in said path by detecting a change in said detecting voltage; and

determining whether a wire in said connection circuit is open based on said change in detecting voltage.

18. The method of claim 17, further comprising:

processing said detecting voltage to output a voltage reading; and

comparing said voltage reading with a voltage range to determine whether said wire is open.

19. The method of claim 17, further comprising converting said detecting voltage in analog to said voltage reading in digital.

20. The method of claim 17, further comprising storing a status flag that indicates whether said wire is open.