BATTERY MONITOR CIRCUIT, STORAGE APPARATUS, ELECTRONIC APPARATUS, ELECTRIC-POWERED VEHICLE, AND POWER SYSTEM

• US 20160072282A1
• Filed: 11/02/2015
• Published: 03/10/2016
• Est. Priority Date: 06/30/2011
• Status: Active Grant

• Current Assignee: Murata Manufacturing Co Limited
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Kumagai, Eiji, Sampei, Akira, Yanagihara, Kazuharu
• Granted Patent: US 9,966,759 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B60L 50/51 characterised by AC-motors
• 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: H02J 1/10 Parallel operation of dc sources
• CPC Class Codes: H02J 7/0014 Circuits for equalisation of charge between batteries
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries

Abstract

A battery monitor circuit includes a first monitoring unit for detecting voltages of battery cells in a first group, a second monitoring unit for detecting voltages of battery cells in a second group, and a current cancellation unit for canceling a difference between first and second currents that flow through the first and second monitoring units, respectively. One terminal of a series connection of the battery cells in the first and second groups and one terminal of the first monitoring unit are connected, the other terminal of the first monitoring unit and one terminal of the second monitoring unit are connected, and the other terminal of the second monitoring unit and the other terminal of the series connection are connected. The current cancellation unit is disposed between a connection point between the first and second monitoring units and a middle connection point in the middle of the series connection.

Claims

1. A battery monitor circuit comprising:

a first monitoring unit configured to detect voltages of battery cells included in a first group;

a second monitoring unit configured to detect voltages of battery cells included in a second group; and

a current cancellation unit configured to cancel a differential current that is a difference between a first current flowing through the first monitoring unit and a second current flowing through the second monitoring unit, and

wherein the battery cells included in the first group and the battery cells included in the second group form a series connection,

wherein one terminal of the series connection and one power terminal of the first monitoring unit are connected, the other power terminal of the first monitoring unit and one power terminal of the second monitoring unit are connected, and the other power terminal of the second monitoring unit and the other terminal of the series connection are connected, and

wherein the current cancellation unit is disposed between a connection point between the other power terminal of the first monitoring unit and one power terminal of the second monitoring unit and a middle connection point in the middle of the series connection.

2. The battery monitor circuit according to claim 1,

wherein the current cancellation unit is an operational amplifier having a negative-side input terminal connected to the connection point, a positive-side input terminal connected to the middle connection point, and an output terminal connected to the negative-side input terminal, and

wherein positive-side power and negative-side power for the operational amplifier are supplied from one terminal and the other terminal of the series connection, respectively.

3. The battery monitor circuit according to claim 1,

wherein the current cancellation unit is an operational amplifier having a negative-side input terminal connected to the connection point, a positive-side input terminal connected to the middle connection point, and an output terminal connected to the negative-side input terminal, and

wherein one terminal of the series connection is connected to a positive-side power terminal of the operational amplifier via a first power supply circuit, and the other terminal of the series connection is connected to a negative-side power terminal of the operational amplifier via a second power supply circuit.

4. The battery monitor circuit according to claim 1, wherein cell balance control is performed so that charging amounts of the battery cells in the series connection are equal to one another.

5. A storage apparatus comprising:

a series connection of a plurality of battery cells; and

a battery monitor circuit configured to detect voltages of the plurality of battery cells, and

wherein the plurality of battery cells in the series connection are classified into at least two groups, a first group and a second group,

wherein the battery monitor circuit includes,

a first monitoring unit configured to detect voltages of battery cells included in the first group,

a second monitoring unit configured to detect voltages of battery cells included in the second group, and

a current cancellation unit configured to cancel a differential current that is a difference between a first current flowing through the first monitoring unit and a second current flowing through the second monitoring unit,

wherein one terminal of the series connection and one power terminal of the first monitoring unit are connected, the other power terminal of the first monitoring unit and one power terminal of the second monitoring unit are connected, and the other power terminal of the second monitoring unit and the other terminal of the series connection are connected, and

wherein the current cancellation unit is disposed between a connection point between the other power terminal of the first monitoring unit and one power terminal of the second monitoring unit and a middle connection point in the middle of the series connection.

6. A storage apparatus comprising the storage apparatus according to claim 5, and

wherein power is supplied to an electronic apparatus connected to the storage apparatus.

7. An electronic apparatus that receives power from the storage apparatus according to claim 5.

8. An electric-powered vehicle comprising:

a conversion apparatus configured to receive power from the storage apparatus according to claim 5 and convert the power into a driving force for the vehicle; and

a control apparatus configured to perform information processing related to vehicle control on the basis of information about the storage apparatus.

9. A power system comprising a power information transmission and receiving unit configured to transmit and receive a signal to and from another apparatus via a network, and

wherein, with information received by the power information transmission and receiving unit, charging control and discharging control are performed on the storage apparatus according to claim 5.

10. A power system that receives power from the storage apparatus according to claim 5 or supplies power from a generator or a power network to the storage apparatus.