CELL CONTROLLER AND BATTERY-MONITORING DEVICE

• US 20150340883A1
• Filed: 01/25/2013
• Published: 11/26/2015
• Est. Priority Date: 01/25/2013
• Status: Active Grant

• Current Assignee: Hitachi Astemo Ltd. (Hitachi, Ltd.)
• Original Assignee: Hitachi Automotive Systems Limited (Hitachi, Ltd.)
• Inventors: KANAI, Tomonori, KIKUCHI, Mutsumi, KUDOH, Akihiko, MIURA, Hikaru, NODA, Mitsuo
• Granted Patent: US 9,755,453 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H01M 10/482 for several batteries or cells simultaneously or sequentially
• CPC Class Codes: H01M 2010/4271 Battery management systems including electronic circuits, e.g. control of current or voltage to keep battery in healthy state, cell balancing
• CPC Class Codes: H01M 2220/20 Batteries in motive systems, e.g. vehicle, ship, plane
• CPC Class Codes: H02J 7/0016 using shunting, discharge or bypass circuits
• CPC Class Codes: H02J 7/00306 Overdischarge protection
• CPC Class Codes: H02J 7/0048 Detection of remaining charge capacity or state of charge [SOC]
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 90/16 Information or communication technologies improving the operation of electric vehicles

Abstract

A cell controller in a battery-monitoring device that monitors an assembled battery having a single cell group or a plurality of cell groups, each made up with a plurality of battery cells connected in series, includes: a startup terminal to which a first discharge resistor is connected and a startup voltage is applied; and a cell-balancing unit that executes cell balancing operation in order to adjust charge levels of the plurality of battery cells during a time period through which the startup voltage remains equal to or greater than a predetermined voltage, wherein: the startup voltage is applied for a predetermined length of time by a first timer unit that includes a passive element capable of accumulating electric energy and capable of discharging electric energy to the startup terminal.

Claims

1. A battery-monitoring device that monitors an assembled battery having a single cell group or a plurality of cell groups, each made up with a plurality of battery cells connected in series, comprising:

a cell controller that is started up in response to a startup voltage applied thereto and includes a cell-balancing unit that executes cell balancing operation in order to adjust charge levels of the plurality of battery cells during a time period through which the startup voltage remains equal to or greater than a predetermined voltage;

a control unit that applies the startup voltage to the cell controller and controls the cell controller;

a first timer unit that includes a passive element capable of accumulating/discharging electric energy and applies the startup voltage to the cell controller for a predetermined length of time to the startup terminal, wherein;

the control unit can be engaged in operation in a low power consumption mode for minimizing power consumption, and the control unit does not apply the startup voltage equal to or greater than the predetermined voltage to the cell controller when the control unit is engaged in operation in the low power consumption mode; and

after the control unit shifts into the low power consumption mode, the first timer unit applies the startup voltage equal to or greater than the predetermined voltage to the cell controller for the predetermined length of time.

2. The battery-monitoring device according to claim 1, wherein:

the passive element included in the first timer unit is a capacitor; and

the electric energy accumulated in the capacitor is discharged to the cell controller at a time constant determined based upon a capacitance of the capacitor.

3. The battery-monitoring device according to claim 1, wherein:

the first timer unit is built into the cell controller.

5. The battery-monitoring device according to claim 1, wherein:

the predetermined length of time changes in correspondence to a voltage value of the startup voltage applied by the control unit to the cell controller.

6. The battery-monitoring device according to claim 5, wherein:

the control unit further includes a voltage-setting unit that sets a voltage value for the startup voltage to be applied to the cell controller.

8. The battery-monitoring device according to claim 5, further comprising:

a second timer unit that counts a length of time elapsing after the control unit shifts into the low power consumption mode and starts up the control unit from the low power consumption mode when the length of elapsing time becomes equal to a specific time length, wherein;

the control unit further includes a time setting unit that sets the specific time length.

9. The battery-monitoring device according to claim 8, wherein:

the cell controller further includes a voltage-measuring unit that measures voltages of the plurality of battery cells during the time period through which the startup voltage remains equal to or greater than the predetermined voltage;

the control unit further includes a decision-making unit that makes a decision, based upon voltage measurement results provided by the voltage-measuring unit, as to whether or not the cell balancing operation needs to be executed by the cell-balancing unit; and

the control unit makes the decision by the decision-making unit after the control unit is started up from the low power consumption mode by the second timer unit.

10. The battery-monitoring device according to claim 9, wherein:

the cell controller further comprises an open/close control unit that opens/closes a transmission path used to discharge the electric energy accumulated in the capacitor; and

when the decision-making unit decides that the cell balancing operation does not need to be executed, the control unit engages the open/close control unit in the cell controller in operation to close the transmission path.

4. (canceled)

7. (canceled)