JP2014239611A - Battery module and battery pack system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To ensure high reliability while satisfying request for large power supply.SOLUTION: A plurality of battery modules according to an embodiment are capable of being connected in series between a high potential side power supply terminal and low potential side power supply terminal which configure a battery pack device. A battery module includes a battery unit which comprises a plurality of battery cells capable of being charged/discharged and is connected between the high potential side power supply terminal and low potential side power supply terminal. A normally open contact unit includes a normally open contact capable of being connected in series with a control signal line for closing or opening a closed circuit for power transfer between the battery unit and an external apparatus through the high potential side power supply terminal and low potential side power supply terminal. A monitoring control unit detects a state of the battery unit, and performs open/close control of the normally open contact unit.

Description

  Embodiments described herein relate generally to a battery module and an assembled battery system.

  Conventionally, in order to apply a lithium ion battery (LIB) to industrial equipment and in-vehicle equipment, since one cell has a low voltage, it is necessary to always connect cells in series to form an assembled battery (for example, , See Patent Document 1).

  In addition, in order to meet the demand for high power supply, there is an increasing demand for higher capacity in a system that uses an assembled battery as a drive power supply or auxiliary power supply in order to improve performance and extend the usable time. ing.

  As a technique for this purpose, an assembled battery device is used in which a number of batteries are connected in series to form a battery group, and the battery group is connected in parallel to form an assembled battery. In this case, in order to facilitate the handling of the battery, a plurality of batteries may be connected in parallel and in series and modularized to form a battery module.

JP 2009-277647 A

  By the way, when the assembled battery system is configured by using a plurality of battery modules, and communication is performed between the battery modules and the cooperative operation is performed, it is possible to eliminate the possibility that a communication abnormality occurs due to external noise or the like. Can not.

For this reason, in an assembled battery system that requires high reliability, it is desirable to construct the system electrically without using communication.
Therefore, an object of the present invention is to provide a battery module and an assembled battery system that can ensure high reliability while meeting the demand for large power supply.

The battery module of the embodiment is a battery module that can be connected between a plurality of high-potential-side power terminals and low-potential-side power terminals that constitute the assembled battery device.
The battery unit of the battery module includes a plurality of chargeable / dischargeable battery cells, and is connected between the high potential side power supply terminal and the low potential side power supply terminal.

The normally open contact portion is a control signal for closing or opening a closed circuit for power transfer between the battery unit and an external device via the high potential side power supply terminal and the low potential side power supply terminal. It has a normally open contact that can be connected in series to the line.
On the other hand, the monitoring control unit detects the state of the battery unit and performs opening / closing control of the normally open contact portion.

FIG. 1 is a schematic configuration block diagram when the assembled battery system of the first embodiment is applied to an electric system of a power backup system. FIG. 2 is a schematic configuration block diagram of the assembled battery system. FIG. 3 is a schematic configuration block diagram when the assembled battery system of the second embodiment is applied to an electric system of a power backup system. FIG. 4 is an explanatory diagram of a schematic configuration of the battery module of the third embodiment. FIG. 5 is an operation processing flowchart for cell balancing according to the third embodiment.

Next, embodiments will be described with reference to the drawings.
[1] First Embodiment FIG. 1 is a schematic configuration block diagram when the assembled battery system of the first embodiment is applied to an electric system of a power backup system.
The electric system 10 of the power supply backup system is roughly classified, and is charged by receiving power supply from the power conversion circuit 13 and power conversion circuit 13 that performs power conversion from the commercial AC power supply 11 and supplies it to the load 12. An assembled battery system 14 that supplies power to the load 12 as a backup target when the commercial AC power supply 11 cannot supply power to the load 12 via the power conversion circuit 13 due to a power failure or the like. Yes.

FIG. 2 is a schematic configuration block diagram of the assembled battery system.
The assembled battery system 14 includes a high-potential power supply terminal 21 and one of a pair of contact terminals connected to the high-potential power supply terminal 21 and one of a pair of coil terminals connected to the relay drive high-potential power supply RLH. The discharge relay 22, the first backflow prevention diode 23 whose cathode terminal K is connected to the other contact terminal of the discharge relay 22, and one of the pair of contact terminals are connected to the high potential side power supply terminal 21. The charging relay 24 connected in parallel to the discharging relay 22 and the anode terminal A are connected to the other contact terminal of the charging relay 24, and the cathode terminal K is connected to the anode terminal A of the first backflow prevention diode 23. And a second backflow prevention diode 25.

  Further, the assembled battery system 14 includes (assembled) battery modules BM1, BM2,... BMn (n is an integer of 2 or more) and one of a pair of coil terminals connected to the relay driving high potential side power supply RLH. Is connected to the other coil terminal of the common relay 26, the anode terminal A is connected to the other coil terminal, and the cathode terminal K is connected to the other coil terminal of the discharge relay 22. And a fourth backflow prevention diode 28 having an anode terminal A connected to the anode terminal A of the backflow prevention diode 27 and a cathode terminal K connected to the other coil terminal of the charging relay 24.

In the above configuration, since the battery modules BM1, BM2,..., BMn have the same configuration, the battery module BM1 will be described as an example.
The battery module BM1 includes a high potential side power supply terminal 31, a low potential side power supply terminal 32, a plurality of battery cells 33 connected in series between the high potential side power supply terminal 31 and the low potential side power supply terminal 32, and a plurality of battery cells 33. A battery management unit (BMU) 34 that functions as a monitoring control unit that monitors the state of the battery cell 33 and controls the connection between the plurality of battery cells 33 and the power conversion circuit 13.

  Further, the battery module BM1 is connected between the pair of discharge control terminals 35, and is in a closed (on) state when the plurality of battery cells 33 are in a dischargeable state under the control of the BMU 34. It is connected between a contact (normally open contact) 36 and a pair of charge control terminals 37, and is closed (on) when a plurality of battery cells 33 are in a chargeable state under the control of the BMU 34. And a second normally open contact (normally open contact) 38.

Here, the connection state of each battery module will be described.
The high potential side power supply terminal 31 of the battery module BM1 is connected to a connection point between the anode terminal A of the first backflow prevention diode 23 and the cathode terminal K of the second backflow prevention diode 25. One discharge control terminal 35 of the battery module BM1 is connected to the coil terminal of the discharge relay 22, and one charge control terminal 37 is connected to the coil terminal of the charge relay 24.

  The high potential side power supply terminal 31 of the battery module BM2 is connected to the low potential side power supply terminal 32 of the battery module BM1. Further, one discharge control terminal 35 of the battery module BM2 is connected to the other discharge control terminal 35 of the battery module BM1, and one charge control terminal 37 is connected to the other charge control terminal 37 of the battery module BM1. Yes.

  Similarly, the high potential side power supply terminal 31 of the battery module BMx (3 ≦ x <n: x is an integer) is connected to the low potential side power supply terminal 32 of the battery module BM (x−1). Further, one discharge control terminal 35 of the battery module BMx is connected to the other discharge control terminal 35 of the battery module BM (x-1), and one charge control terminal 37 is connected to the battery module BM (x-1). The other charge control terminal 37 is connected.

  Furthermore, the high potential side power supply terminal 31 of the battery module BMn is connected to the low potential side power supply terminal 32 of the battery module BM (n−1). In addition, one discharge control terminal 35 of the battery module BMn is connected to the other discharge control terminal 35 of the battery module BM (n−1), and one charge control terminal 37 is connected to the battery module BM (n−1). The other charge control terminal 37 is connected.

  As a result, between the relay driving high potential side power supply RLH and the relay driving low potential side power supply RLL, a plurality of first coils corresponding to the coils constituting the discharge relay 22 and the battery modules BM1 to BMn are provided. The normally open contact 36 is connected in series. Here, the signal line connecting the coil-relay driving low potential side power source RLL constituting the relay driving high potential side power source RLH and the discharging relay 22 constitutes a discharge control signal line.

  Further, between the relay driving high potential side power supply RLH and the relay driving low potential side power supply RLL, a plurality of second normally open coils corresponding to the coils constituting the charging relay 24 and the battery modules BM1 to BMn are provided. The contacts 38 are connected in series. Here, the signal line connecting the coil-relay driving low potential side power source RLL constituting the relay driving high potential side power source RLH and the charging relay 24 constitutes a charging control signal line.

Therefore, if the first normally open contact 36 corresponding to at least one of the plurality of BMUs 34 corresponding to the battery modules BM1 to BMn is kept open, the discharge relay 22 remains open. It becomes.
Similarly, when the second normally open contact 38 corresponding to at least one of the plurality of BMUs 34 corresponding to the battery modules BM1 to BMn is kept open, the charging relay 24 remains open. It becomes.

Next, the operation of the first embodiment will be described.
In this case, in the initial state, the battery modules BM1 to BMn are assumed to be in a fully charged state.

First, the operation when the battery modules BM1 to BMn perform discharge will be described.
The BMU 34 corresponding to each of the battery modules BM1 to BMn monitors the terminal voltage of the plurality of battery cells 33, and no power is supplied from the power conversion circuit 13, that is, power is supplied to the load 12 due to a power failure or the like. When it is determined that it is necessary to supply, the first normally open contact 36 is closed.

  When the first normally open contact 36 corresponding to the BMU 34 of all the battery modules BM1 to BMn is closed, a voltage is applied to the coil terminal of the discharging relay 22 from the relay driving high potential side power supply RLH. The normally open contact of the discharge relay 22 is closed.

  Therefore, the high potential side power supply terminal 21, the first backflow prevention diode 23, the battery modules BM1 to BMn, and the low potential side power supply terminal 22 are closed as discharge circuits, and the electric power stored in the battery modules BM1 to BMn is loaded. 12 and the load 12 continues to drive.

Next, the operation when the battery modules BM1 to BMn are charged will be described.
The BMU 34 corresponding to each of the battery modules BM <b> 1 to BMn monitors the terminal voltages of the plurality of battery cells 33 and determines that it is necessary to charge the plurality of battery cells 33 with the power supplied from the power conversion circuit 13. In such a case, the second normally open contact 38 is closed.

  When the second normally open contact 38 corresponding to the BMU 34 of all the battery modules BM1 to BMn is closed, a voltage is applied to the coil terminal of the charging relay 24 from the relay driving high potential side power supply RLH. The normally open contact of the charging relay 24 is closed.

  Therefore, the high potential side power supply terminal 21, the second backflow prevention diode 25, the battery modules BM1 to BMn, and the low potential side power supply terminal 22 are closed as a charging circuit, and power is supplied to the battery modules BM1 to BMn from the power conversion circuit 13. The plurality of battery cells 33 supplied and constituting the battery modules BM1 to BMn are charged and store electric power.

As described above, according to the first embodiment, it is not necessary to communicate with each other in order to link the battery modules BM <b> 1 to BMn, and it is possible to perform discharging or charging with effective cooperation. .
Therefore, since it is not necessary to perform communication with low reliability, the reliability of the system can be improved.
In this embodiment, the BMU 34 performs state monitoring and control of the load and the main power supply. However, these functions may be executed separately for the BMU and BCU (Battery Control Unit).

[2] Second Embodiment FIG. 3 is a schematic configuration block diagram when the assembled battery system of the second embodiment is applied to an electric system of a power backup system.
In FIG. 3, the same parts as those in the assembled battery system of FIGS. 1 and 2 are denoted by the same reference numerals.

  In the following description, the assembled battery system 14A is used in place of the assembled battery system 14 in FIG.

  The assembled battery system 14A includes a high-potential-side power supply terminal 21, a shared relay 26 in which one of a pair of coil terminals is connected to the relay-drive high-potential-side power supply RLH, a low-potential-side power supply terminal 32, and a high-potential-side power supply. And a plurality of battery units 41-1 to 41-n connected to the terminal 21, the other coil terminal of the common relay 26, and the low-potential-side power supply terminal 32, respectively.

  In the above configuration, since the plurality of battery units 41-1 to 41-n have the same configuration, the battery unit 41-1 will be described.

  The battery unit 41-1 has a discharge relay 22 in which one of a pair of contact terminals is connected to the high potential side power supply terminal 21 and one of a pair of coil terminals is connected to the relay drive high potential side power supply RLH. The cathode terminal K is connected to the other contact terminal of the discharge relay 22, the first backflow prevention diode 23, and one of the pair of contact terminals is connected to the high potential side power supply terminal 21 and connected in parallel to the discharge relay 22. The charging relay 24, the anode terminal A is connected to the other contact terminal of the charging relay 24, and the cathode terminal K is connected to the anode terminal A of the first backflow prevention diode 23. The battery modules BM1, BM2,..., BMn (n is an integer of 2 or more) connected in series to the relay driving high potential side power source RLH of the shared relay 26 are connected. The anode terminal A is connected to the other coil terminal not connected, and the cathode terminal K is connected to the anode terminal A of the third backflow prevention diode 27 and the third backflow prevention diode 27 connected to the other coil terminal of the discharge relay 22. And a fourth backflow prevention diode 28 having an anode terminal A connected thereto and a cathode terminal K connected to the other coil terminal of the charging relay 24.

Next, the operation of the second embodiment will be described.
In this case, in the initial state, the battery modules BM1 to BMn constituting each of the battery units 41-1 to 41-n are assumed to be in a fully charged state. Further, the battery modules BM1 to BMn constituting each of the battery units 41-1 to 41-n can operate independently.

First, an operation when the battery modules BM1 to BMn of the battery units 41-1 to 41-n perform discharge will be described.
The BMU 34 corresponding to each of the battery modules BM1 to BMn of each battery unit 41-1 to 41-n monitors the terminal voltage of the plurality of battery cells 33, that is, no power is supplied from the power conversion circuit 13, that is, When it is determined that power needs to be supplied to the load 12 due to a power failure or the like, the first normally open contact 36 is closed.

  And among the battery units 41-1 to 41-n, the first normally open contacts 36 corresponding to the BMUs 34 of all the battery modules BM1 to BMn of at least one battery unit (for example, the battery unit 41-1) are closed. In this case, a voltage is applied to the coil terminal of the discharge relay 22 from the relay driving high potential side power source, and the normally open contact of the discharge relay 22 is closed.

In parallel with this, the normally open contact of the shared relay is closed.
Therefore, the high potential side power supply terminal 21 of the battery unit 41-x (x: an integer of 1 to n) in which the first normally open contacts 36 corresponding to the BMUs 34 of all the battery modules BM1 to BMn are in the closed state, the first The backflow prevention diode 23, the battery modules BM1 to BMn, and the low potential side power supply terminal 22 are closed as a discharge circuit, and the electric power stored in the battery modules BM1 to BMn is supplied to the load 12, and the load 12 is driven. Will continue.

Next, an operation when the battery modules BM1 to BMn of the battery units 41-1 to 41-n are charged will be described.
The BMU 34 corresponding to each of the battery modules BM1 to BMn of each battery unit 41-1 to 41-n monitors the terminal voltage of the plurality of battery cells 33 and is supplied to the plurality of battery cells 33 from the power conversion circuit 13. When it is determined that it is necessary to perform charging with the electric power, the second normally open contact 38 is closed.

  When the second normally open contact 38 corresponding to the BMU 34 of all the battery modules BM1 to BMn is closed, a voltage is applied to the coil terminal of the charging relay 24 from the relay driving high potential side power supply RLH. The normally open contact of the charging relay 24 is closed.

Therefore, the high potential side power supply terminal 21, the second backflow prevention diode 25, the battery modules BM1 to BMn, and the low potential side power supply terminal 22 are closed as a charging circuit, and power is supplied to the battery modules BM1 to BMn from the power conversion circuit 13. The plurality of battery cells 33 supplied and constituting the battery modules BM1 to BMn are charged and store electric power.
The operation of the battery unit 41-1 is also performed independently in parallel in the other battery units 41-2 to 41-n.

As described above, according to the second embodiment as well, it is not necessary to communicate with each other in order to link the battery modules BM <b> 1 to BMn, and it is possible to perform discharging or charging with effective cooperation.
Therefore, since it is not necessary to perform communication with low reliability, the reliability of the system can be improved.
In this embodiment, the BMU 34 performs state monitoring and control of the load and the main power supply. However, these functions may be executed separately for the BMU and BCU (Battery Control Unit).

[3] Third Embodiment Each of the above embodiments does not consider the cell balance of the plurality of battery cells 33 constituting the battery modules BM1 to BMn, but the third embodiment considers the cell balance. This is an embodiment.
FIG. 4 is an explanatory diagram of a schematic configuration of the battery module of the third embodiment.
FIG. 5 is an operation processing flowchart for cell balancing according to the third embodiment.
Since the battery modules BM1 to BMn have the same configuration, in FIG. 4, the battery module BM1 will be described as an example including four battery units.

The BMU 34 corresponding to the battery module BM1 determines whether or not the cell voltage of the battery cell 33 having the highest voltage among the battery cells 33 constituting the battery module BM1 is equal to or higher than the predetermined voltage Vth1 (step S11). ).
In the determination of step S11, when the cell voltage of the battery cell 33 having the highest voltage among the battery cells 33 constituting the battery module BM1 is less than the predetermined voltage Vth1 (step S11; No), charging is performed. It will be in a standby state to continue.

  In the determination of step S11, when the cell voltage of the battery cell 33 having the highest voltage among the battery cells 33 constituting the battery module is equal to or higher than the predetermined voltage Vth1 (step S11; Yes), the voltage exceeds the predetermined voltage. The discharge resistance switch corresponding to the battery cell 33 having the cell voltage is closed (ON state), and the stored power of the battery cell 33 is discharged through the discharge resistor 52 (step S12).

Subsequently, the BMU 34 corresponding to the battery module BM1 determines whether the cell voltage of the battery cell 33 having the highest voltage among the battery cells 33 constituting the battery module BM1 is less than a predetermined voltage Vth2 (<Vth1). Is determined (step S13).
In the determination in step S13, when the cell voltage of the battery cell 33 having the highest voltage among the battery cells 33 constituting the battery module BM1 is equal to or higher than the predetermined voltage Vth2 (step S13; No), charging is performed. It will be in a standby state to continue.

  In the determination of step S13, when the cell voltage of the battery cell 33 having the highest voltage among the battery cells 33 constituting the battery module is less than the predetermined voltage Vth2 (step S13; Yes), the predetermined voltage Vth2 The discharge resistance switch corresponding to the battery cell 33 that has become less than the open state is opened (off state), the process proceeds to step S11 again, and the same process is performed thereafter.

As a result, the battery cells 33 constituting the battery module BM1 can be charged up to a fully charged state, and the fully charged state can be maintained.
As a result, the battery cell 33 which comprises several battery module BM1-BMn can be charged to a full charge state, and can hold | maintain the said full charge state.

[4] Modification of Embodiment In the above embodiment, the discharging relay 22 and the charging relay 24 are provided on the high potential side power line, and the common relay 26 is provided on the low potential side power line. 22 and the charging relay 24 may be provided on the low potential side power line, and the common relay 26 may be provided on the high potential side power line.
The control program executed by the battery module or the assembled battery system of the present embodiment may be configured to be provided by being incorporated in advance in a ROM or the like.
The control program executed by the battery module or the assembled battery system of the present embodiment is a file in an installable format or an executable format, and is a CD-ROM, flexible disk (FD), CD-R, DVD (Digital Versatile Disk). For example, the program may be recorded on a computer-readable recording medium.

  Furthermore, the control program executed by the battery module or the assembled battery system of the present embodiment may be stored on a computer connected to a network such as the Internet and provided by being downloaded via the network. . Moreover, you may comprise so that the control program run with the battery module or assembled battery system of this embodiment may be provided or distributed via networks, such as the internet.

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

DESCRIPTION OF SYMBOLS 10 Electric system 11 Commercial AC power supply 12 Load 13 Power conversion circuit 14, 14A Battery assembly system 21 High potential side power supply terminal 22 Discharge relay 23 1st backflow prevention diode 24 Charging relay 25 2nd backflow prevention diode 26 Shared relay 27 1st 3 Backflow prevention diode 28 4th backflow prevention diode 31 High potential side power supply terminal 32 Low potential side power supply terminal 33 Battery cell 34 BMU
35 discharge control terminal 36 first normally open contact 37 charge control terminal 38 second normally open contact 41-1 to 41-n battery unit 52 discharge resistance A anode terminal BM to BMn battery module RLH relay driving high potential side power supply RLL relay Low-potential side power supply for driving Vth predetermined voltage BM1 to BMn Battery module Vth1 predetermined voltage Vth2 predetermined voltage

Claims (8)

A battery module connectable between a plurality of high potential side power supply terminals and low potential side power supply terminals constituting the assembled battery device,
A plurality of chargeable / dischargeable battery cells, a battery unit connected between the high potential side power supply terminal and the low potential side power supply terminal,
Can be connected in series to a control signal line for closing or opening a closed circuit for power transfer between the battery unit and an external device via the high potential side power supply terminal and the low potential side power supply terminal A normally open contact portion having a normally open contact;
A monitoring control unit that detects the state of the battery unit and performs open / close control of the normally open contact unit;
Battery module with The control signal line is a discharge control signal line for closing or opening a discharge circuit for discharging the battery unit to supply power to an external device;
A charging control signal line for closing or opening a charging circuit for charging the battery unit in response to power supply from an external device capable of supplying power; and
The normally open contact portion includes a first normally open contact that can be connected in series to the discharge control signal line, and a second normally open contact that can be connected in series to the charge control signal line.
The battery module according to claim 1. The monitoring control unit detects the state of the battery unit, and performs control to close the first normally open contact when the battery unit satisfies a predetermined discharge condition,
When the battery unit satisfies a predetermined charging condition, the second normally open contact is controlled to be closed.
The battery module according to claim 2. The battery unit has a cell balance circuit for balancing the battery cells when charging the battery cells,
The supervisory control unit controls the cell balance circuit;
The battery module according to any one of claims 1 to 3. A high potential side power supply terminal;
A low-potential side power supply terminal;
A battery unit comprising the battery module according to any one of claims 1 to 4, wherein a plurality of the high potential side power supply terminals and the low potential side power supply terminals are connected.
An assembled battery system comprising: In the battery unit, the battery modules are connected in series.
The assembled battery system according to claim 5. A plurality of the battery units are connected in parallel between the high potential side power supply terminal and the low potential side power supply terminal,
The assembled battery system according to claim 5 or 6. A discharge relay provided on either one of the high potential side power line or the low potential side power line and connected to the discharge control line;
A charging relay connected in parallel with the discharging relay and connected to the charging control line;
Of the high potential side power line or the low potential side power line, a shared relay provided on the other,
An assembled battery system according to any one of claims 5 to 7, further comprising:

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