Battery voltage monitoring apparatus

• US 8,330,469 B2
• Filed: 01/04/2008
• Issued: 12/11/2012
• Est. Priority Date: 01/05/2007
• Status: Active Grant

• Current Assignee: Renesas Electronics Corporation
• Original Assignee: Renesas Electronics Corporation
• Inventors: Miyamoto, Manabu
• Primary Examiner(s): Tso, Edward
• Assistant Examiner(s): TORRES RUIZ, JOHALI ALEJANDRA
• Application Number:
  US12/007,028
• Publication Number:
  US 20080164881A1
• Time in Patent Office: 1,803 Days
• Field of Search: 324/429, 324/433
• US Class Current: 324/433
• CPC Class Codes: G01R 15/04 Voltage dividers
• CPC Class Codes: G01R 19/16542 for batteries charge condition monitoring in G01R31/36
• 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: G01R 31/396 Acquisition or processing of data for testing or for monitoring individual cells or groups of cells within a battery

Abstract

A battery voltage monitoring apparatus monitoring an assembled battery voltage, the assembled battery including a plurality of battery cells, includes a voltage sensor detecting potential of the plurality of battery cells; an output logic circuit outputting a potential detect signal based on an output of the voltage sensor, the potential detect signal representing that abnormal potential is detected; and a delay circuit adding certain delay to the output of the voltage sensor and outputting the delayed voltage detect signal to the output logic circuit; wherein, the voltage sensor comprises at least one comparator having hysteresis characteristic, and detects the potential of the battery cell based on an output of the comparator.

Claims

1. A battery voltage monitoring apparatus for monitoring an assembled battery voltage, the assembled battery including a plurality of battery cells, said battery voltage monitoring apparatus comprising:

a plurality of input terminals, each input terminal connected to the plurality of battery cells respectively through a potential measurement line;

a voltage sensor connected to plurality of input terminals the voltage sensor detecting a potential of the plurality of battery cells;

an output logic circuit outputting a potential detect signal based on an output of the voltage sensor, the potential detect signal representing that an abnormal potential is detected; and

a current source,

wherein the voltage sensor comprises;

a reference voltage generating circuit generating a reference voltage; and

a comparator having a hysteresis characteristic and comprising a first terminal and a second terminal, the second terminal inputting the reference voltage, and

wherein one end of the current source is connected between the one of the plurality of input terminals and the first terminal, and the output of the voltage sensor is generated based on an output of the comparator.

2. The battery voltage monitoring apparatus according to claim 1, wherein the comparator having the hysteresis characteristic shorts at least a part of a resistor connected to an input terminal of the comparator according to the output of the comparator, so that said hysteresis characteristic is obtained.

3. The battery voltage monitoring apparatus according to claim 1, further comprising a level shift circuit connected between a delay circuit to add a certain delay to an output of the voltage sensor and the output logic circuit.

4. The battery voltage monitoring apparatus according to claim 3, wherein the delay circuit comprises a resistance component and a capacitance component.

5. The battery voltage monitoring apparatus according to claim 1, further comprising:

a first input terminal, a second input terminal, and a third input terminal each connected to the plurality of battery cells through a first voltage measurement line, a second voltage measurement line, and a third voltage measurement line, respectively;

a first resistor connected to the first and second input terminals, the first resistor to maintain a potential deference between the first and the second input terminals at a first certain value on a condition that there is no disconnection of the first and the second voltage measurement lines; and

a second resistor connected to the second and the third input terminals, the second resistor to maintain a potential difference between the second and the third input terminals at a second certain value on a condition that there is no disconnection of the second and the third voltage measurement line.

8. The battery voltage monitoring apparatus according to claim 1, wherein the comparator having a hysteresis characteristic comprises a comparator for excess voltage detection to detect an excess voltage of the battery cell.

9. The battery voltage monitoring apparatus according to claim 1, wherein the voltage sensor comprises:

a first resistor queue connected to the plurality of battery cells in parallel;

a second resistor queue connected to the plurality of battery cells in parallel; and

a comparator being supplied with a divided point of the first resistor queue to one input terminal, and being supplied with an output potential to the other input terminal, and

wherein the comparator having a hysteresis characteristic comprises;

a switching element shorting a part of the first resistor queue; and

a comparator being supplied with the first resistor queue connected to the switching element to one input terminal.

10. The battery voltage monitoring apparatus according to claim 9, wherein the comparator being supplied with the first resistor queue operates the switching element upon detection of an excess voltage signal.

11. The battery voltage monitoring apparatus according to claim 9, wherein the switching element is connected between the divided point and the one input terminal.

12. The battery voltage monitoring apparatus according to claim 1, wherein the comparator having the hysteresis characteristic comprises a switch for hysteresis.

13. The battery voltage monitoring apparatus according to claim 1, further comprising a delay circuit configured to add a certain delay to the output of the voltage sensor and outputting the delayed potential detect signal to the output logic circuit.

6. The battery voltage monitoring apparatus according to claim , wherein the battery voltage monitoring apparatus comprises a plurality of voltage sensor modules, each voltage sensor module including a plurality of voltage sensors, and

wherein the comparator having a hysteresis characteristic is provided to the voltage sensor, the voltage sensor is connected to a terminal, the terminal is supplied with a source potential of the voltage sensor module.

7. The battery voltage monitoring apparatus according to claim 6, further comprising a plurality of current sources, wherein first ends of the respective current sources are connected between a corresponding one of the plurality of input terminals and a corresponding one of the plurality of battery cells.

14. A battery voltage monitoring apparatus monitoring an assembled battery voltage, the assembled battery including a plurality of battery cells, comprising:

a plurality of input terminals, each input terminal connected to the plurality of battery cells respectively through a potential measurement line;

a voltage sensor connected to one of the plurality of input terminals, the voltage sensor detecting a potential of each of the plurality of battery cells;

an output logic circuit outputting a potential detect signal based on an output of the voltage sensor, the potential detect signal representing that an abnormal potential is detected; and

a current source,

wherein the voltage sensor comprises;

a reference voltage generating circuit generating a reference voltage; and

a comparator having a hysteresis characteristic and comprising a first terminal and a second terminal, the second terminal inputting the reference voltage, and

wherein one end of the current source is connected between the one of the plurality of input terminals and the first terminal, and the output of the voltage sensor is generated based on an output of the comparator.

15. The battery voltage monitoring apparatus according to claim 14, wherein the comparator having the hysteresis characteristic shorts at least a part of a resistor connected to an input terminal of the comparator according to the output of the comparator, so that said hysteresis characteristic is obtained.

16. The battery voltage monitoring apparatus according to claim 14, further comprising a level shift circuit connected between a delay circuit to add a certain delay to an output of the voltage sensor and the output logic circuit.

17. The battery voltage monitoring apparatus according to claim 14, wherein the battery voltage monitoring apparatus comprises a plurality of voltage sensor modules, each voltage sensor module including a plurality of voltage sensors, and

wherein the comparator having the hysteresis characteristic is provided to the voltage sensor, the voltage sensor is connected to terminals setting a source potential of the voltage sensor module.

18. The battery voltage monitoring apparatus according to claim 17, further comprising a plurality of current sources, wherein first ends of the respective current sources are connected between a corresponding one of the plurality of input terminals and a corresponding one of the plurality of battery cells.

19. The battery voltage monitoring apparatus according to claim 14, further comprising a delay circuit configured to add a certain delay to the output of the voltage sensor and outputting the delayed potential detect signal to the output logic circuit.

20. A battery voltage monitoring apparatus monitoring an assembled battery voltage, the assembled battery including a plurality of battery cells, comprising:

a plurality of input terminals, each input terminal connected to the plurality of battery cells respectively through a potential measurement line;

a voltage sensor connected to one of the plurality of input terminals, the voltage sensor detecting a potential of each of the plurality of battery cells; and

a current source,

wherein the voltage sensor comprises;

a reference voltage generating circuit generating a reference voltage; and

a comparator having a hysteresis characteristic and comprising a first terminal and a second terminal, the second terminal inputting the reference voltage, and

wherein one end of the current source is connected between the one of the plurality of input terminals and the first terminal, and the output of the voltage sensor is generated based on an output of the comparator.