JP2017208983A - Composite battery system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a composite battery system capable of keeping safety even when a failure occurs in a voltage sensor, a current sensor, a temperature sensor, etc. provided in a lithium ion secondary battery and capable of improving user's convenience and saving labor and time in system construction.SOLUTION: A composite battery system 10 includes: a plurality of battery units 20 connected in parallel to one another; and a composite battery control unit 22. Each of the plurality of battery units 20 comprises: a plurality of composite batteries 30 connected in series/in parallel to one another; and a unit isolator 32 capable of electrically separating the plurality of composite batteries 30. Each of the plurality of composite batteries 30 includes a voltage detector 54 for detecting a voltage value of each composite battery 30. The composite battery control unit 22, depending on a signal from the voltage detector 54, opens/closes the unit isolator 32.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a composite battery system using a composite battery comprising a lead storage battery and a lithium ion secondary battery.

  Conventional automobiles mainly using fossil fuel as driving energy have an adverse effect on the global environment due to the exhaust gas. On the other hand, the use of more electric vehicles that do not emit exhaust gas or hybrid vehicles that significantly reduce their emissions is greatly expected from the viewpoint of environmental improvement, and effective use of surplus power at night is also expected. It is also recommended from a point of view. Furthermore, it is desired to provide a distributed power storage system for stabilizing the power supply.

  On the other hand, the conventional lead-acid battery has a problem that the stored energy per weight is small because it is very heavy, and in order to solve this problem, a composite battery in which two types of secondary batteries having different properties are combined is disclosed. Yes. For example, Patent Document 1 discloses a composite battery that can increase the retained energy per weight by connecting a lead storage battery and a lithium ion secondary battery in parallel, and can particularly improve low-temperature power performance. It is disclosed.

  Conventional lithium-ion secondary batteries have a risk of explosion, fire, and explosion due to overcharge, etc., and therefore there is a problem that a protection switch and a protection circuit are necessary. Although it is possible to absorb the overcharge of the secondary battery, it has been common to provide a protection switch and a protection circuit as usual in order to provide redundancy for safety. Patent Document 1 discloses that a protection circuit mounted on a circuit unit monitors the voltage, current, temperature, and the like of an auxiliary battery such as a lithium ion secondary battery, and shuts off the circuit when an abnormality occurs.

JP 2014-175128 A

  However, it is not expected that each sensor provided in the lithium ion secondary battery will fail, and in that case, there is a problem that the protection circuit cannot shut off the circuit of the lithium ion secondary battery.

  The present invention has been made in view of such a conventional problem, and the object of the present invention is, even when a voltage sensor, a current sensor, a temperature sensor or the like provided in a lithium ion secondary battery fails, It is an object of the present invention to provide a composite battery system that can maintain safety, improve user convenience, and save time and effort for system construction.

  In order to achieve the above object, the present inventor has conducted extensive research, and as a result, in addition to the voltage sensor, current sensor, temperature sensor, etc. provided in the lithium ion secondary battery, the voltage value is assigned to each composite battery. The voltage provided to the lithium ion secondary battery by installing a voltage detector to detect, opening and closing the unit disconnector of the composite battery unit according to the signal from the voltage detector, and electrically disconnecting in units of the composite battery unit It has been found that safety can be maintained even when a sensor, a current sensor, a temperature sensor, or the like fails.

  Further, the present inventor has found that the convenience of the user can be improved by arranging the device that the user needs to access outside the housing for housing the plurality of composite battery units. Has been reached.

  That is, the present invention includes a plurality of composite batteries connected in series and / or in parallel with each other and a unit disconnector capable of electrically disconnecting the plurality of composite batteries, respectively, and a plurality of power supplies connected in parallel to each other. A composite battery unit and a composite battery control unit connected to each of the plurality of unit disconnectors, each of the plurality of composite batteries, a sub-module, a lead storage battery connected in parallel to the sub-module, A voltage detector for detecting a voltage value of each composite battery, and the submodule includes a plurality of lithium ion secondary batteries connected in series and / or in parallel with each other, and a plurality of lithium ion secondary batteries A sub-module disconnector that can be electrically disconnected, and a sub-module controller connected to the sub-module disconnector, and a composite battery control The knit opens and closes the unit disconnector in response to a signal from the voltage detector, and the sub-module control device has at least one of over-temperature, over-current, over-charge and over-discharge in each lithium ion secondary battery constituting the sub-module. The present invention provides a composite battery system that opens and closes a sub-module disconnector when it is detected.

Here, in the above, a housing for housing a plurality of composite battery units, a connection terminal for connecting an external device, a breaker connected between the unit disconnector and the connection terminal, The composite battery control unit, the connection terminal, and the breaker are preferably disposed outside the housing.
When at least one of overtemperature, overcurrent, overcharge, and overdischarge is detected in each lithium ion secondary battery that constitutes the submodule, the submodule control device includes a plurality of lithium ion secondary batteries that constitute the submodule. The sub-module disconnector corresponding to the sub-module is operated so as to electrically disconnect the secondary battery, and the composite battery control unit detects that at least one of overcharge and overdischarge is detected by the voltage detector. It is preferable to operate the unit disconnector corresponding to the composite battery unit so as to electrically disconnect a plurality of composite batteries included in the same composite battery unit as the composite battery including the voltage detector.
The withstand voltages of the submodule disconnector, the submodule controller and the voltage detector are preferably higher than the maximum voltage of the composite battery and lower than the maximum voltage of the composite battery system.

  According to the present invention, safety can be maintained even when a voltage sensor, a current sensor, a temperature sensor, or the like provided in a lithium ion secondary battery fails, and the convenience of the user is improved and the time and labor for system construction are increased. And save time.

FIG. 1 is a block diagram showing a composite battery system of the present invention. FIG. 2 is a block diagram showing a composite battery constituting the composite battery system of FIG.

  Hereinafter, a composite battery system of the present invention will be described in detail based on preferred embodiments shown in the accompanying drawings. FIG. 1 is a block diagram showing a composite battery system of the present invention, and FIG. 2 is a block diagram showing a composite battery constituting the composite battery system of FIG.

  The composite battery system 10 of the present invention includes a plurality of composite battery units 20 and a composite battery control unit 22 connected in parallel to each other. Each of the plurality of composite battery units 20 includes a plurality of composite batteries 30 connected in series and / or in parallel to each other, and a unit disconnector 32 that can electrically disconnect the plurality of composite batteries 30. It is. The composite battery control unit 22 is connected to each of the plurality of unit disconnectors 32. As an example, FIG. 1 shows three composite battery units 20 connected in parallel to each other, and 24 composite batteries 30 connected in parallel and four in series.

  Each of the plurality of composite batteries 30 includes a submodule 40, a lead storage battery 52 connected in parallel to the submodule 40, and a voltage detector 54 for detecting the voltage value of each composite battery 30. is there. The submodule 40 includes a plurality of lithium ion secondary batteries 42 connected in series and / or in parallel to each other, a submodule disconnector 44 capable of electrically disconnecting the plurality of lithium ion secondary batteries 42, And a sub-module control device 46 connected to the module disconnector 44. The some lithium ion secondary battery 42 which comprises the submodule 40 of this invention may also contain a lithium ion secondary battery cell. The lead storage battery 52 constituting the composite battery 30 of the present invention may be a plurality of lead storage batteries connected in series and / or in parallel.

  The composite battery control unit 22 opens and closes the unit disconnector 32 by a signal from the voltage detector 54. The submodule control device 46 opens and closes the submodule disconnector 44 when at least one of overtemperature, overcurrent, overcharge and overdischarge is detected in each lithium ion secondary battery 42 constituting the submodule 40. Is.

  For example, as the submodule 40 in the composite battery 30, two submodules 40 each having a plurality of lithium ion secondary batteries 42 connected so that the rated voltage is 24V may be connected in parallel and used. it can. Further, as the lead storage battery 52 in the composite battery 30, two sets of two lead storage batteries having a rated voltage of 12 V connected in series with each other can be connected in parallel.

  The overtemperature is set to detect, for example, 61 ° C. or more or 0 ° C. or less, the overcurrent is set to detect, for example, 81 to 117 A or more, and the overcharge is, for example, a single cell For example, the overdischarge is set to detect 2.4 V or less per unit cell.

  With such a configuration, the composite battery system of the present invention can maintain safety even when a voltage sensor, a current sensor, a temperature sensor, or the like provided in the lithium ion secondary battery fails.

  The composite battery system 10 of the present invention may further include a housing 62, a connection terminal 64, and a breaker 66. The housing 62 is for housing a plurality of composite battery units 20. The connection terminal 64 is for connecting the external device 70. The breaker 66 is connected between the unit disconnector 32 and the connection terminal 64. The composite battery control unit 22, the connection terminal 64, and the breaker 66 are disposed outside the housing 62. The external device 70 is, for example, a PCS (Power Conditioning System).

  That is, when the composite battery control unit 22 is arranged outside the housing 62, it is easier to access at the time of software change or program input. It is easier to connect the external device 70 to the connection terminal 64 when the connection terminal 64 is disposed outside the housing 62. When the breaker 66 is disposed outside the housing 62, it is easier to access when the composite battery system 10 is manually detached. With this configuration, user convenience can be improved.

  The sub-module control device 46 of the composite battery system 10 of the present invention, when at least one of over-temperature, over-current, over-charge and over-discharge is detected in each lithium ion secondary battery 42 constituting the sub-module 40, The submodule disconnector 44 corresponding to the submodule 40 may be operated so that the plurality of lithium ion secondary batteries 42 constituting the submodule 40 are electrically disconnected.

  The composite battery control unit 22 includes a plurality of composite battery units 20 included in the same composite battery unit 20 as the composite battery 30 including the voltage detector 54 when at least one of overcharge and overdischarge is detected by the voltage detector 54. The unit disconnector 32 corresponding to the composite battery unit 20 may be operated so that the composite battery 30 is electrically disconnected. In this case, the remaining composite battery unit 20 can be used continuously.

  With such a configuration, the composite battery system of the present invention can maintain safety even when a voltage sensor, a current sensor, a temperature sensor, or the like provided in the lithium ion secondary battery fails.

  The composite battery system 10 of the present invention has a plurality of composite batteries 30 connected in series and / or in parallel. Each of the plurality of composite batteries 30 includes a submodule 40, a lead storage battery 52 connected in parallel to the submodule 40, and a voltage detector 54 for detecting the voltage value of each composite battery 30. is there. The submodule 40 includes a plurality of lithium ion secondary batteries 42 connected in series and / or in parallel to each other, a submodule disconnector 44 capable of electrically disconnecting the plurality of lithium ion secondary batteries 42, And a sub-module control device 46 connected to the module disconnector 44.

  The submodule control device 46 opens and closes the submodule disconnector 44 when at least one of overtemperature, overcurrent, overcharge and overdischarge is detected in each lithium ion secondary battery 42 constituting the submodule 40. Is. The withstand voltages of the submodule disconnector 44, the submodule controller 46 and the voltage detector 54 are higher than the maximum voltage of the composite battery 30 and lower than the maximum voltage of the composite battery system 10.

  Usually, the withstand voltage of an electric circuit of a system including a lithium ion secondary battery needs to be higher than the maximum voltage of the system. However, in the composite battery 30, since the lead storage battery 52 always regulates the maximum voltage of the composite battery 30 as a power source, the withstand voltage of the electric circuit of the composite battery system 10 is higher than the maximum voltage of the composite battery 30 and is combined. The voltage can be lower than the maximum voltage of the battery system 10. For example, the withstand voltages of the submodule disconnector 44, the submodule controller 46, and the voltage detector 54 are less than 50V, higher than the maximum voltage 28.8V of the composite battery 30, and lower than the system voltage 72 to 1000V.

By adopting such a configuration, the composite battery system of the present invention does not need to design an electric circuit in consideration of the system voltage every time the system is constructed, so that it is possible to save time and effort for system construction.
The composite battery system of the present invention is basically configured as described above.

  The composite battery system of the present invention has been described in detail above. However, the present invention is not limited to the above description, and various improvements and modifications may be made without departing from the spirit of the present invention. .

  The composite battery system of the present invention can maintain safety even when a voltage sensor, a current sensor, a temperature sensor or the like provided in a lithium ion secondary battery breaks down, and enhances user convenience and system construction. This is industrially useful because it can save labor and time.

DESCRIPTION OF SYMBOLS 10 Composite battery system 20 Composite battery unit 22 Composite battery control unit 30 Composite battery 32 Unit disconnector 40 Submodule 42 Lithium ion secondary battery 44 Submodule disconnector 46 Submodule controller 52 Lead storage battery 54 Voltage detector 62 Case 64 Connection terminal 66 Breaker 70 External device

Claims (4)

A plurality of composite battery units connected in parallel with each other, each comprising a plurality of composite batteries connected in series and / or in parallel and a unit disconnector capable of electrically disconnecting the plurality of composite batteries;
A composite battery control unit connected to each of the plurality of unit disconnectors,
Each of the plurality of composite batteries includes a sub module, a lead storage battery connected in parallel to the sub module, and a voltage detector for detecting a voltage value of each composite battery,
The submodule includes a plurality of lithium ion secondary batteries connected in series and / or in parallel to each other, a submodule disconnector capable of electrically disconnecting the plurality of lithium ion secondary batteries, and the submodule. A sub-module control device connected to the disconnector,
The composite battery control unit opens and closes the unit disconnector by a signal from the voltage detector,
The sub-module control device is a composite that opens and closes the sub-module disconnector when at least one of over-temperature, over-current, over-charge and over-discharge is detected in each lithium ion secondary battery constituting the sub-module. Battery system. Furthermore, a housing for storing the plurality of composite battery units, a connection terminal for connecting an external device, and a breaker connected between the unit disconnector and the connection terminal,
The composite battery system according to claim 1, wherein the composite battery control unit, the connection terminal, and the breaker are disposed outside the housing. The submodule control device is configured to detect a plurality of lithium ions constituting a submodule when at least one of overtemperature, overcurrent, overcharge and overdischarge is detected in each lithium ion secondary battery constituting the submodule. Operate the sub-module disconnector corresponding to the sub-module so as to electrically disconnect the ion secondary battery,
When at least one of overcharge and overdischarge is detected by the voltage detector, the composite battery control unit electrically connects a plurality of composite batteries included in the same composite battery unit as the composite battery including the voltage detector. The combined battery system according to claim 1 or 2, wherein the unit disconnector corresponding to the combined battery unit is operated so as to be disconnected. A composite battery system having a plurality of composite batteries connected in series and / or in parallel with each other,
Each of the plurality of composite batteries includes a sub module, a lead storage battery connected in parallel to the sub module, and a voltage detector for detecting a voltage value of each composite battery,
The submodule includes a plurality of lithium ion secondary batteries connected in series and / or in parallel to each other, a submodule disconnector capable of electrically disconnecting the plurality of lithium ion secondary batteries, and the submodule. A sub-module control device connected to the disconnector,
The submodule control device opens and closes the submodule disconnector when at least one of overtemperature, overcurrent, overcharge and overdischarge is detected in each lithium ion secondary battery constituting the submodule,
A combined battery system in which a withstand voltage of the submodule disconnector, the submodule control device, and the voltage detector is higher than a maximum voltage of the composite battery and lower than a maximum voltage of the composite battery system.

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