Battery voltage monitoring apparatus

• US 20080164881A1
• Filed: 01/04/2008
• Published: 07/10/2008
• Est. Priority Date: 01/05/2007
• Status: Active Grant

• Current Assignee: Renesas Electronics Corporation
• Original Assignee: NEC Electronics Corporation (Renesas Electronics Corporation)
• Inventors: Miyamoto, Manabu
• Granted Patent: US 8,330,469 B2
• Time in Patent Office: Days
• US Class Current: 324/429
• 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 monitoring an assembled battery voltage, the assembled battery including a plurality of battery cells, comprising;

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.

2. The battery voltage monitoring apparatus according to claim 1, wherein

the comparator having hysteresis characteristic shorts at least a part of resistor connected to an input terminal of the comparator according to the output of the comparator, so that hysteresis characteristic is obtained.

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

a level shift circuit connected between the delay circuit and the output logic circuit.

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

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

and

a plurality of current sources connected to the plurality of input terminals, the current source applying current through the plurality of input terminals on the condition that there is no disconnection of the potential measurement line.

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

a first, a second, and a third input terminals connected to the plurality of battery cells through a first, a second, and a third voltage measurement lines respectively;

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

6. The battery voltage monitoring apparatus according to claim 1, wherein

the battery voltage monitoring apparatus comprises a plurality of voltage sensor modules, each voltage sensor module including a plurality of voltage sensors, and

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

7. The battery voltage monitoring apparatus according to claim 1, wherein

the delay circuit comprises resistance component and capacitance component.

8. The battery voltage monitoring apparatus according to claim 1, wherein

the comparator having hysteresis characteristic is a comparator for excess voltage detection detecting 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 battery cell in parallel;

a second resistor queue connected to the battery cell in parallel; and

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

the comparator having 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. A battery voltage monitoring apparatus monitoring an assembled battery voltage, the assembled battery including a plurality of battery cells, comprising;

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 a comparator operating with output potential of battery cell as potential source, the battery cell being an object to be monitored, and

the comparator has hysteresis characteristic.

11. The battery voltage monitoring apparatus according to claim 10, wherein

the comparator having hysteresis characteristic shorts at least a part of resistor connected to an input terminal of the comparator according to the output of the comparator, so that hysteresis characteristic is obtained.

12. The battery voltage monitoring apparatus according to claim 10, further comprising,

a level shift circuit connected between the delay circuit and the output logic circuit.

13. The battery voltage monitoring apparatus according to claim 10, further comprising,

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

and

a plurality of current sources connected to the plurality of input terminals, the current source applying current through the plurality of input terminals on the condition that there is no disconnection of the potential measurement line.

14. The battery voltage monitoring apparatus according to claim 10, wherein

the battery voltage monitoring apparatus comprises a plurality of voltage sensor modules, each voltage sensor module including a plurality of voltage sensors, and

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

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

a comparator detecting potential of the battery cell, and outputting a potential signal representing results of detection based on certain hysteresis characteristic;

a delay circuit adding certain delay to the potential signal; and

a logic circuit outputting a potential detect signal based on an output of the delay circuit.