JP2024067196A - Battery pack system, battery module, edge module, and parallelization module - Google Patents

Abstract

[Problem] To provide a battery pack system, a battery module, an end module, and a paralleling module that can easily increase the degree of commonality. [Solution] A battery pack system includes a battery string 3 in which a plurality of battery modules 2 are connected in a row and have a first end 31 and a second end 32, and an end module 4 connected to the second end 32 of the battery string 3, and each battery module 2 includes a first positive terminal Tp1, a first negative terminal Tm1, a second positive terminal Tp2, a second negative terminal Tm2, a positive side path portion 21, and a negative side path portion 22, and between adjacent battery modules 2, the first positive terminal Tp1 of one side is electrically connected to the second positive terminal Tp2 of the other side, and the first negative terminal Tm1 of one side is electrically connected to the second negative terminal Tm2 of the other side, and at least one of the positive side path portion 21 and the negative side path portion 22 includes a power storage unit B1 and switching elements SW1, SW2 that switch the connection state of the power storage unit B1, and a third positive terminal Tp3 of the end module 4 is electrically connected to a third negative terminal Tm3. [Selected Figure] Figure 1

Description

The present invention relates to a battery pack system including a battery, a battery module, an end module, and a parallelization module.

In recent years, battery packs installed in electric vehicles have become known (see, for example, Patent Document 1).

Patent Publication 2022-115495

However, the required electrical specifications, such as voltage, of electric vehicles vary depending on the model and manufacturer. The required electrical specifications, such as voltage, of motor-driven devices other than electric vehicles also vary. This makes it difficult to standardize battery packs.

The object of the present invention is to provide a battery pack system, a battery module, an end module, and a paralleling module that facilitates increasing the degree of commonality.

The battery pack system according to the present invention comprises a battery string in which a plurality of battery modules are connected in a row and has a first end and a second end, and an end module connected to the second end of the battery string, and each of the battery modules comprises a first positive terminal and a first negative terminal provided on the first end side of each of the battery modules, a second positive terminal and a second negative terminal provided on the second end side of each of the battery modules, a positive side path portion for passing a current between the first positive terminal and the second positive terminal, and a negative side path portion for passing a current between the second negative terminal and the first negative terminal, and when the plurality of battery modules are connected, a current is generated between adjacent battery modules. The first positive terminal on one side and the second positive terminal on the other side, and the first negative terminal on one side and the second negative terminal on the other side are electrically connected, and at least one of the positive side path section and the negative side path section includes a storage unit that stores electric charge, and a switching circuit that switches the connection state including an insertion state in which the storage unit is inserted into the current path in the at least one path section and a removal state in which the storage unit is removed from the current path, and the end module includes a third positive terminal connected to the second positive terminal and a third negative terminal connected to the second negative terminal of the battery module located at the second end of the battery string, and the third positive terminal and the third negative terminal are electrically connected.

According to this configuration, the end module is connected to a battery string in which multiple battery modules are connected in a row, and the storage units of the multiple battery modules are connected in series. Therefore, the output voltage can be changed by increasing or decreasing the number of battery modules according to the voltage required for each electric device, such as an electric vehicle. As a result, the battery pack system can be applied to various electric devices, making it easy to increase the degree of commonality. Furthermore, since the output waveform can be changed by dynamically changing the number of series connections of the storage units using a switching circuit, it is possible to adapt the voltage waveform required for each electric device, making it easy to increase the degree of commonality.

The positive side path section preferably includes the storage unit and the switching circuit that switches between connection states including the joining state in which the storage unit is added to the current path of the positive side path section and the disconnection state in which the storage unit is disconnected from the current path of the positive side path section, and the negative side path section preferably includes the storage unit and the switching circuit that switches between connection states including the joining state in which the storage unit is added to the current path of the negative side path section and the disconnection state in which the storage unit is disconnected from the current path of the negative side path section.

With this configuration, a storage unit is provided on both the positive path and the negative path of each battery module, making it easy to increase the number of storage units connected in series.

It is also preferable that each of the battery modules further includes a first communication terminal provided on the first end side of each of the battery modules and a second communication terminal provided on the second end side of each of the battery modules, and that when the plurality of battery modules are connected, the first communication terminal of one of the battery modules and the second communication terminal of the other battery module are electrically connected between adjacent battery modules, and that each of the battery modules further includes an internal module control unit that switches the connection state by the switching circuit in response to control information obtained from the first communication terminal or the second communication terminal.

With this configuration, it is possible to control the switching of the connection state of each battery module by inputting a control signal to a first communication terminal provided at a first end of the battery string or a second communication terminal provided at a second end of the battery string.

It is also preferable that the control unit further includes a control unit that outputs a first signal, which is a combination of the control information for each battery module in the order in which the battery modules are connected in the battery string, to the first communication terminal of the battery module located at the first end, and the module control unit acquires the control information combined with one end of the first signal obtained from the first communication terminal of its own battery module as its own control information, and outputs the remaining signal, obtained by deleting the control information for itself from the first signal, as a new first signal to the second communication terminal of its own battery module.

With this configuration, the control unit only needs to output control information for each battery module to the first communication terminal of the battery module located at the first end by connecting the battery modules in the order in which they are connected, and there is no need for the communication address of the destination battery module. Therefore, even when adding, removing, or replacing battery modules, there is no need to set a communication address for each battery module.

It is preferable that each of the battery modules further includes a third communication terminal provided on the second end side of each of the battery modules and a fourth communication terminal provided on the first end side of each of the battery modules, and that the module control unit connects module information related to its own battery module to one end of the second signal obtained from the third communication terminal of its own battery module and outputs the resulting new second signal to the fourth communication terminal of its own battery module.

According to this configuration, a second signal in which the module information of each battery module is connected in the order in which the battery modules are connected is output from the fourth communication terminal at the first end of the battery string. Therefore, even if a communication address is not set in the destination battery module, it is possible to correctly obtain the module information of each battery module from the second signal. As a result, even when adding, removing, or replacing battery modules, there is no need to set a communication address in each battery module.

It is also preferable that the module control unit connects module information related to its own battery module to one end of the second signal obtained from the second communication terminal of its own battery module and outputs the resulting new second signal to the first communication terminal of its own battery module.

This configuration allows the communication terminal to be used for both transmission and reception.

It is also preferable that the control unit further includes a control unit that outputs a first signal, which is a combination of the control information for each battery module in the order in which the battery modules are connected in the battery string, to the second communication terminal of the battery module located at the second end, and the module control unit acquires the control information combined with one end of the first signal obtained from the second communication terminal of its own battery module as its own control information, and outputs the remaining signal, obtained by deleting the control information for itself from the first signal, as a new first signal to the first communication terminal of its own battery module.

With this configuration, the control unit only needs to output control information for each battery module to the second communication terminal of the battery module located at the second end by connecting the battery modules in the order in which they are connected, and there is no need for the communication address of the destination battery module. Therefore, even when adding, removing, or replacing battery modules, there is no need to set a communication address for each battery module.

It is preferable that each of the battery modules further includes a third communication terminal provided on the second end side of each of the battery modules and a fourth communication terminal provided on the first end side of each of the battery modules, and that the module control unit connects module information related to its own battery module to one end of the second signal obtained from the fourth communication terminal of its own battery module and outputs the resulting new second signal to the third communication terminal of its own battery module.

According to this configuration, a second signal in which the module information of each battery module is connected in the order in which the battery modules are connected is output from a third communication terminal at the second end of the battery string. Therefore, even if a communication address is not set in the destination battery module, it is possible to correctly obtain the module information of each battery module from the second signal. As a result, even when adding, removing, or replacing battery modules, there is no need to set a communication address in each battery module.

It is also preferable that the module control unit connects module information related to its own battery module to one end of the second signal obtained from the first communication terminal of its own battery module and outputs the resulting new second signal to the second communication terminal of its own battery module.

This configuration allows the communication terminal to be used for both transmission and reception.

It is also preferable that the end module further includes an inductor interposed between the third positive terminal and the third negative terminal, and an intermediate connection terminal that is electrically connected to the midpoint of the inductor.

This configuration makes it possible for the battery pack system to operate as an inverter circuit.

The battery array further includes a parallelization module for connecting the battery arrays in parallel, the parallelization module being provided for each battery array and including a first positive connection terminal connected to the first positive terminal of the battery module located at the first end, a first negative connection terminal connected to the first negative terminal of the battery module located at the first end, a positive output terminal and a positive parallel terminal in electrical conduction with the first positive connection terminal, and a negative output terminal and a negative parallel terminal in electrical conduction with the first negative connection terminal, the first positive connection terminal and the first negative connection terminal being located on the outer surface of the parallelization module in a direction perpendicular to the column direction of the battery array, and the positive parallel terminal and the negative parallel terminal being located on the outer surface of the parallelization module opposite to the first positive connection terminal and the first negative connection terminal.

With this configuration, it is possible to connect multiple battery strings in parallel by connecting multiple battery strings connected with parallelization modules in a direction perpendicular to the row direction of the battery strings. As a result, it is possible to increase the current capacity of the battery pack system.

It is also preferable that the parallelization module further includes a filter that smoothes the voltage obtained from the first positive connection terminal and the first negative connection terminal.

With this configuration, the output voltage of each battery string is smoothed by the filter, reducing momentary differences in output voltage between multiple battery strings connected in parallel. As a result, the momentary input/output of current between battery strings can be reduced.

It is also preferable that each battery module includes a plurality of the power storage units, and the switching circuit switches the connection state for each of the power storage units.

With this configuration, each battery module contains multiple power storage units, making it easy to increase the number of series-connected power storage units in the entire battery pack system.

The battery module according to the present invention is the battery module used in the above-mentioned battery pack system.

This configuration makes it easier to increase the degree of commonality with the battery pack system described above.

The end module of the present invention is the end module used in the above-mentioned battery pack system.

This configuration makes it easier to increase the degree of commonality with the battery pack system described above.

The parallelization module according to the present invention is the parallelization module used in the above-mentioned battery pack system.

This configuration makes it easier to increase the degree of commonality with the battery pack system described above.

Battery pack systems, battery modules, end modules, and paralleling modules configured in this way make it easy to increase the degree of commonality.

1 is a perspective view showing an example of the appearance of a battery pack system according to one embodiment of the present invention; FIG. 2 is a perspective view showing the outline of the appearance of the battery module, the end module, and the parallelization module shown in FIG. 1 . 2 is a block diagram illustrating an example of an electrical configuration of the series block illustrated in FIG. 1. FIG. 2 is a schematic circuit diagram for explaining the configuration of a unit module. FIG. 11 is a conceptual circuit diagram showing an example of a unit module EM using a full bridge as a switching circuit. 10 is an explanatory diagram for explaining an example of a transmission and reception operation of a first serial signal; FIG. 11 is an explanatory diagram for explaining an example of a transmission and reception operation of a second serial signal; FIG. FIG. 13 is an explanatory diagram for explaining a parallel connection of series blocks. 2 is a schematic perspective view showing another embodiment of the battery pack system shown in FIG. 1. FIG. 10 is a schematic circuit diagram of the battery pack system shown in FIG. 9 . 10 is a schematic perspective view showing another embodiment of the battery pack system shown in FIG. 9. FIG. 12 is a schematic circuit diagram of the battery pack system shown in FIG. 11 . 10 is a schematic perspective view showing another embodiment of the battery pack system shown in FIG. 9. FIG. 14 is a schematic circuit diagram of the battery pack system shown in FIG. 13. 12 is a schematic perspective view showing another embodiment of the battery pack system shown in FIG. 11. FIG. 16 is a schematic circuit diagram of the battery pack system shown in FIG. 15 . 16 is a schematic perspective view showing another embodiment of the battery pack system shown in FIG. 15. FIG. 18 is a schematic circuit diagram of the battery pack system shown in FIG. 17.

The following describes an embodiment of the present invention with reference to the drawings. Note that components with the same reference numerals in each drawing are the same, and their description will be omitted. In each drawing, XYZ orthogonal coordinate axes are appropriately shown to clarify the directional relationships. Figure 1 is a perspective view showing an example of the external appearance of a battery pack system according to one embodiment of the present invention.

The battery pack system 1 shown in FIG. 1 generally comprises a plurality of battery modules 2, a plurality of end modules 4, and a plurality of paralleling modules 5. The battery modules 2, the end modules 4, and the paralleling modules 5 each have a housing that is approximately rectangular parallelepiped shaped.

The multiple battery modules 2 are connected in a row along the X direction to form a battery string 3. The +X side end of the battery string 3 is the first end 31, and the -X side end of the battery string 3 is the second end 32. In other words, the +X direction is the first end 31 side, and the -X direction is the second end 32 side.

An end module 4 is connected to the second end 32 of the battery string 3, and a parallelization module 5 is connected to the first end 31 of the battery string 3. A battery pack system 1 is formed by connecting multiple series blocks 11, each of which is made up of a parallelization module 5, a battery string 3, and an end module 4, in the Y-axis direction. The battery modules 2, end modules 4, and parallelization modules 5 are detachable from one another.

Figure 2 is a perspective view that shows a schematic appearance of the battery module 2, end module 4, and parallelization module 5 shown in Figure 1. A first positive terminal Tp1, a first negative terminal Tm1, a first communication terminal Tc1, and a fourth communication terminal Tc4 are provided on the +X side outer wall surface of the battery module 2. A second positive terminal Tp2, a second negative terminal Tm2, a second communication terminal Tc2, and a third communication terminal Tc3 are provided on the -X side outer wall surface of the battery module 2.

A third positive terminal Tp3, a third negative terminal Tm3, a fifth communication terminal Tc5, and a sixth communication terminal Tc6 are provided on the +X side outer wall surface of the end module 4. An intermediate connection terminal Ti is provided on the +Z side outer wall surface of the end module 4. Note that the intermediate connection terminal Ti is not limited to being provided on the +Z side outer wall surface, but may also be provided on the -Z side or -X side outer wall surface.

The -X side outer wall surface of the paralleling module 5 is provided with a first positive connection terminal Tpc1, a first negative connection terminal Tmc1, a first communication connection terminal Tcc1, and a second communication connection terminal Tcc2. The -Y side outer wall surface of the paralleling module 5, which is perpendicular to the X direction, is provided with a positive output terminal Tpo and a negative output terminal Tmo. The +Y side outer wall surface of the paralleling module 5, which is perpendicular to the X direction and is opposite the positive output terminal Tpo and the negative output terminal Tmo, is provided with a positive parallel terminal Tpp and a negative parallel terminal Tmp. The positive output terminal Tpo and the negative output terminal Tmo may be provided on the +Y side outer wall surface, and the positive parallel terminal Tpp and the negative parallel terminal Tmp may be provided on the -Y side outer wall surface.

When multiple battery modules 2 are connected, the first positive terminal Tp1, first negative terminal Tm1, first communication terminal Tc1, and fourth communication terminal Tc4 of one battery module are connected to the second positive terminal Tp2, second negative terminal Tm2, second communication terminal Tc2, and third communication terminal Tc3 of the other battery module.

When the battery module 2 located at the second end 32 and the end module 4 are connected, the second positive terminal Tp2, the second negative terminal Tm2, the second communication terminal Tc2, and the third communication terminal Tc3 of the battery module 2 located at the second end 32 are connected to the third positive terminal Tp3, the third negative terminal Tm3, the fifth communication terminal Tc5, and the sixth communication terminal Tc6 of the end module 4, respectively.

In addition, when the battery module 2 located at the first end 31 and the parallelization module 5 are connected, the first positive terminal Tp1, the first negative terminal Tm1, the first communication terminal Tc1, and the fourth communication terminal Tc4 of the battery module 2 located at the first end 31 are connected to the first positive connection terminal Tpc1, the first negative connection terminal Tmc1, the first communication connection terminal Tcc1, and the second communication connection terminal Tcc2 of the parallelization module 5, respectively.

When multiple series blocks 11, each of which is made up of a battery module 2, an end module 4, and a parallelization module 5, are connected in the Y direction in this manner, the positive output terminal Tpo and the negative output terminal Tmo of one side are connected to the positive parallel terminal Tpp and the negative parallel terminal Tmp of the other side between adjacent parallelization modules 5.

Figure 3 is a block diagram showing an example of the electrical configuration of the series block 11 shown in Figure 1. Each battery module 2 includes, within its housing, a positive side path section 21 for passing a current between the first positive terminal Tp1 and the second positive terminal Tp2, a negative side path section 22 for passing a current between the second negative terminal Tm2 and the first negative terminal Tm1, and an intra-module control section 23.

The positive path section 21 and the negative path section 22 each include a plurality of unit modules EM. The unit modules EM each have a terminal T1 (first terminal) and a terminal T2 (second terminal).

The multiple unit modules EM in the positive side path section 21 are connected in series, and between adjacent unit modules EM, the terminal T2 of the unit module EM on the high potential side is connected to the terminal T1 of the unit module EM on the low potential side. The terminal T1 of the unit module EM on the highest potential side is connected to the first positive terminal Tp1, and the terminal T2 of the unit module EM on the lowest potential side is connected to the second positive terminal Tp2. As a result, the positive side path section 21 forms a current path from the first positive terminal Tp1 to the second positive terminal Tp2.

The negative side path section 22 is configured similarly to the positive side path section 21, except that the terminal T1 of the unit module EM on the highest potential side is connected to the second negative terminal Tm2, and the terminal T2 of the unit module EM on the lowest potential side is connected to the first negative terminal Tm1. As a result, the negative side path section 22 forms a current path from the second negative terminal Tm2 to the first negative terminal Tm1.

The number of unit modules EM in the positive path section 21, i.e., the number of power storage units B1, may be one, and the number of unit modules EM in the negative path section 22, i.e., the number of power storage units B1, may be one.

Figure 4 is a schematic circuit diagram for explaining the configuration of the unit module EM. The unit module EM includes terminals T1 and T2, a storage unit B1 that stores electric charge, and switching elements SW1 and SW2 (switching circuit) that switch the electrical connection state of the storage unit B1 to the terminals T1 and T2. The switching elements SW1 and SW2 are an example of a switching circuit, and in the example shown in Figure 4, they form a half bridge.

Specifically, the storage unit B1 and the switching element SW1 are connected in series, and the switching element SW2 is connected in parallel to the series circuit of the storage unit B1 and the switching element SW1. The connection point between the switching element SW1 and the switching element SW2 is connected to the terminal T1, and the connection point between the switching element SW2 and the storage unit B1 is connected to the terminal T2.

Terminal T1 is connected to terminal T2 of the unit module EM that is at a higher potential than the own module, and terminal T2 is connected to terminal T1 of the unit module EM that is at a lower potential than the own module. This allows multiple unit modules EM to be connected in series.

Various switching elements can be used as the switching elements SW1 and SW2, and semiconductor switching elements such as transistors can be preferably used. The switching elements SW1 and SW2 are turned on and off in response to a control signal from the module control unit 23.

Various secondary batteries can be suitably used as the power storage unit B1, and are not limited to single cells. A battery pack consisting of multiple secondary batteries may also be used as the power storage unit B1.

The power storage unit B1 of the unit module EM indicated by the symbol A is in a connected state, and the power storage unit B1 of the unit module EM indicated by the symbol B is in a disconnected state. In the connected state, the switching element SW1 is on and the switching element SW2 is off, so that the power storage unit B1 is connected to the current paths of the positive side path portion 21 and the negative side path portion 22. In the disconnected state, the switching element SW1 is off and the switching element SW2 is on, so that the power storage unit B1 is disconnected from the current paths of the positive side path portion 21 and the negative side path portion 22.

The unit module EM may use a full bridge as a switching circuit. FIG. 5 is a conceptual circuit diagram showing an example of a unit module EM using a full bridge as a switching circuit. The full-bridge unit module EM shown in FIG. 5 further includes switching elements SW3 and SW4 in addition to the half-bridge unit module EM shown in FIG. 4. The switching elements SW3 and SW4 may be the same as the switching elements SW1 and SW2.

Specifically, the series circuit of switching elements SW3 and SW4 is connected in parallel with the series circuit of switching elements SW1 and SW2. The connection point of switching elements SW1 and SW2 is connected to terminal T1, and the connection point of switching elements SW3 and SW4 is connected to terminal T2.

The full-bridge unit module EM shown in FIG. 5 can be in the joined state indicated by symbol A, the unjoined state indicated by symbol B, and the inverted state indicated by symbol C. In the unit module EM in the inverted state, the power storage unit B1 is connected with the polarity reversed.

In the join state, switching elements SW1 and SW4 are on, and switching elements SW2 and SW3 are off. In the disconnect state, switching elements SW1 and SW3 are off, and switching elements SW2 and SW4 are on. In the inverted state, switching elements SW1 and SW4 are off, and switching elements SW2 and SW3 are on. Note that in the disconnect state, switching elements SW1 and SW3 may be on, and switching elements SW2 and SW4 may be off.

The module control unit 23 is configured with, for example, a CPU (Central Processing Unit) that executes predetermined logical operations, a RAM (Random Access Memory) that temporarily stores data, a non-volatile storage device, a serial communication circuit, and peripheral circuits thereto, and operates by executing a predetermined program.

The intra-module control unit 23 turns on and off the switching elements SW1 and SW2 in response to control information obtained from the first communication terminal Tc1, and switches the connection state of each unit module EM in the own battery module 2. Hereinafter, the intra-module control unit 23 controlling the switching elements SW1 and SW2 to control the connection state including the join state and the disconnect state, or controlling the switching elements SW1 to SW4 to control the connection state including the join state, the disconnect state, and the inverted state, will be simply described as controlling the connection state.

The end module 4 includes in its housing inductors L1 and L2, an end control unit 41, and a current sensor 42. One end of the inductor L1 is connected to the third positive terminal Tp3, the other end of the inductor L1 is connected to one end of the inductor L2, and the other end of the inductor L2 is connected to the third negative terminal Tm3. That is, the inductors L1 and L2 are interposed between the third positive terminal Tp3 and the third negative terminal Tm3.

The connection point of inductors L1 and L2, i.e., the midpoint of inductors L1 and L2, is conductively connected to intermediate connection terminal Ti. Note that a center-tapped reactor may be used instead of inductors L1 and L2, and the center tap may be connected to intermediate connection terminal Ti.

By providing the end module 4 with inductors L1 and L2, the battery pack system 1 can be operated as an inverter circuit. Note that the end module 4 does not need to include the inductors L1 and L2 and the intermediate connection terminal Ti, and the third positive terminal Tp3 and the third negative terminal Tm3 may be short-circuited.

The current sensor 42 detects the current flowing through the battery string 3 and outputs the current value to the end control unit 41.

The end control unit 41 is configured with, for example, a CPU that executes predetermined logical operations, a RAM that temporarily stores data, a non-volatile storage device, a serial communication circuit, and peripheral circuits therefor, and operates by executing a predetermined program.

The end control unit 41 transmits the current value detected by the current sensor 42 as a second serial signal SS2 (second signal) to the sixth communication terminal Tc6. The transmission and reception operation of the second serial signal SS2 will be described later.

The parallelization module 5 includes a control unit 51 and a filter 52 in its housing. The filter 52 is a so-called LC filter that includes an inductor L interposed between the first positive terminal Tp1 and the positive output terminal Tpo, and a capacitor C interposed between the positive output terminal Tpo and the negative output terminal Tmo. The positive parallel terminal Tpp is conductively connected to the positive output terminal Tpo, and the negative parallel terminal Tmp is conductively connected to the negative output terminal Tmo.

The control unit 51 is configured with, for example, a CPU that executes predetermined logical operations, a RAM that temporarily stores data, a non-volatile storage device, a serial communication circuit, and peripheral circuits therefor, and operates by executing a predetermined program.

The control unit 51 outputs a first serial signal SS1 (first signal) that links control information for each battery module 2 and end module 4 in the order in which the multiple battery modules 2 and end modules 4 are connected in the serial block 11 to the first communication terminal Tc1 of the battery module 2 located at the first end 31 via the first communication connection terminal Tcc1. The transmission and reception operation of the first serial signal SS1 will be described later.

Although the first serial signal SS1 is shown as an example of the first signal and the second serial signal SS2 is shown as an example of the second signal, the first signal and the second signal may be parallel signals. The first communication terminal Tc1 to the sixth communication terminal Tc6, the first communication connection terminal Tcc1, and the second communication connection terminal Tcc2 may be configured as connectors in which conductors are in contact with each other. Or, they may be configured to be connected one-to-one by non-contact means such as radio waves or light.

When the multiple battery modules 2, end modules 4, and paralleling modules 5 configured as described above are connected, the power storage units B1 in the joined state in all the battery modules 2 are connected in series via inductors L1 and L2, and the sum of the output voltages of the power storage units B1 is output as the output voltage Vout of the battery pack system 1 between the positive output terminal Tpo and the negative output terminal Tmo.

The battery pack system 1 can increase or decrease the number of battery modules 2 connected to it, so the output voltage Vout can be changed by increasing or decreasing the number of battery modules 2 according to the voltage required for each electrically-driven device, such as an electric vehicle. Therefore, the battery pack system 1 can be applied to various electrically-driven devices, making it easy to increase the degree of commonality.

Furthermore, since the number of connected storage units B1 can be dynamically changed using the control information, it becomes possible to finely adjust the output voltage Vout according to the charge state and output voltage of the storage unit B1. Furthermore, when the end module 4 is configured to include inductors L1, L2 and an intermediate connection terminal Ti, it becomes possible to operate the battery pack system 1 as an inverter circuit, output a single-phase AC voltage from the intermediate connection terminal Ti using two battery pack systems 1, and output a three-phase AC voltage from the intermediate connection terminal Ti using three battery pack systems 1.

Figure 6 is an explanatory diagram for explaining an example of the transmission and reception operation of the first serial signal SS1. In Figure 6, the battery module 2 located at the first end 31 is described as battery module 2(1), the battery module 2 adjacent to battery module 2(1) is described as battery module 2(2), and the battery module 2 adjacent to battery module 2(2) and located at the second end 32 is described as battery module 2(3). In addition, control information for battery module 2(1) is described as D1, control information for battery module 2(2) is described as D2, control information for battery module 2(3) is described as D3, and control information for end module 4 is described as D4.

First, the control unit 51 transmits a first serial signal SS1, which links the control information D1 to D4 for each battery module 2 and end module 4 in the connection order of each battery module 2 and end module 4, from the first communication connection terminal Tcc1 to the battery module 2(1). In FIG. 6, an example is shown in which the control information D1 to D4 is linked in the connection order from the closest to the parallelization module 5, but the control information D1 to D4 may be linked in the connection order from the furthest from the parallelization module 5.

The module control unit 23 of the battery module 2(1) acquires one end of the first serial signal SS1 obtained from the first communication terminal Tc1 of the battery module 2(1), for example the control information D1 linked to the beginning, and outputs the remaining control information D2 to D4 obtained by deleting the control information D1 from the first serial signal SS1 as a new first serial signal SS1 from the second communication terminal Tc2 of the battery module 2(1) to the battery module 2(2).

The module control unit 23 of the battery module 2(1) controls the connection state of each power storage unit B1 in the battery module 2(1) based on the control information D1 obtained in this manner.

The module control unit 23 of the battery modules 2(2) and 2(3), like the module control unit 23 of the battery module 2(1), acquires its own control information linked to the beginning of the first serial signal SS1 obtained from the first communication terminal Tc1 of its own battery module 2, and outputs the remaining control information obtained by deleting its own control information from the first serial signal SS1 as a new first serial signal SS1 from the second communication terminal Tc2 of its own battery module 2.

The module control units 23 of the battery modules 2(2) and 2(3) control the connection state of each power storage unit B1 in the battery modules 2(2) and 2(3) based on their own control information obtained in this manner.

When the control unit 51 connects the control information D1 to D4 in the order of connection from the furthest from the parallelization module 5, the battery modules 2(1) to 2(3) simply acquire the control information connected to the end of the first serial signal SS1 obtained from the first communication terminal Tc1 as their own control information.

In this way, the control unit 51 can control each battery module 2 and end module 4 by transmitting a first serial signal SS1 in which the control information D1 to D4 is linked in the order in which each battery module 2 and end module 4 is linked, so there is no need to set an address for each battery module 2 and end module 4. Therefore, even if the battery modules 2 are added, removed, or replaced, there is no need to set an address for each battery module 2, making it easy to increase or decrease the number of battery modules 2 according to the voltage required for each electrically-powered device, such as an electric vehicle.

Figure 7 is an explanatory diagram for explaining an example of the transmission and reception operation of the second serial signal SS2. In Figure 7, module information related to battery module 2(1) is indicated as M1, module information related to battery module 2(2) is indicated as M2, module information related to battery module 2(3) is indicated as M3, and module information related to end module 4 is indicated as M4.

First, the end control unit 41 of the end module 4 transmits, for example, a current value detected by the current sensor 42 as module information M4 related to the end module 4 from the sixth communication terminal Tc6 to the battery module 2 (3).

Then, the module control unit 23 of the battery module 2(3) connects the module information M3 related to the battery module 2(3) to one end, for example the terminal end, of the second serial signal SS2 obtained from the third communication terminal Tc3 in the battery module 2(3), and outputs the resulting signal as a new second serial signal SS2 from the fourth communication terminal Tc4 of the battery module 2(3) to the battery module 2(2).

The module control unit 23 can set, for example, the terminal voltage of each storage unit B1 in the battery module 2 (3) and the SOC (State Of Charge) of each storage unit B1 as module information M3. The terminal voltage of each storage unit B1 can be detected, for example, by providing a voltage detection circuit (not shown) in each unit module EM.

The SOC of each storage unit B1 may be obtained from the open circuit voltage of each storage unit B1, for example, by detecting the open circuit voltage of the storage unit B1 in the disconnected state and referring to an open circuit voltage-SOC characteristics table that shows the relationship between the open circuit voltage and the SOC.

Alternatively, a current detection circuit (not shown) may be provided to detect the current flowing through each storage unit B1, and the current flowing through each storage unit B1 may be integrated, with the current value in the charging direction being positive and the current value in the discharging direction being negative, and the SOC of each storage unit B1 may be calculated from the ratio of the integrated current value to the full charge capacity of each storage unit B1.

The module control unit 23 of the battery modules 2(2) and 2(1), like the module control unit 23 of the battery module 2(3), connects the module information about its own battery module 2 to the end of the second serial signal SS2 obtained from the third communication terminal Tc3 of its own battery module 2 to generate a new second serial signal SS2, and outputs it to the fourth communication terminal Tc4 of its own battery module 2.

In addition, each battery module 2(1) to 2(3) may concatenate module information related to its own battery module 2 to the beginning of the second serial signal SS2 to generate a new second serial signal SS2.

In this way, the second serial signal SS2, which concatenates the module information M1 to M4, is received by the second communication connection terminal Tcc2, and the module information M1 to M4 is acquired by the control unit 51 of the parallelization module 5.

With this configuration, it is possible to identify which battery module 2 and end module 4 each piece of module information belongs to by the connection order of the module information M1 to M4 in the second serial signal SS2. Therefore, there is no need to set an address for each battery module 2 and end module 4. As a result, even if the battery modules 2 are added, removed, or replaced, there is no need to set an address for each battery module 2, making it easy to increase or decrease the number of battery modules 2 according to the voltage required for each electrically-powered device, such as an electric vehicle.

The control unit 51 can also obtain module information M1-M4 related to each battery module 2 and end module 4 by receiving the second serial signal SS2. The control unit 51 can then control the connection state of the power storage unit B1 in each battery module 2 by transmitting control information D1-D4 based on the module information M1-M4 as the first serial signal SS1.

As a result, the control unit 51 can individually control the output of each unit module EM in each battery module 2, allowing the battery pack system 1 to operate as a so-called modular multilevel converter (MMC). Furthermore, while the MMC can in principle only change the output voltage Vout in steps of the voltage width of the power storage unit B1, by combining it with PWM (Pulse Width Modulation) control technology, it becomes possible to output intermediate voltages between steps as the output voltage Vout.

In addition, if the SOC, temperature, continuous current-carrying time, continuous rest time, etc. of each storage unit B1 are treated as module information, the control unit 51 can determine the control contents of the connection state for each storage unit B1 based on this information, thereby making it possible to stably operate the battery pack system 1 and reduce deterioration of the storage unit B1.

In addition, the fourth communication terminal Tc4 and the third communication terminal Tc3 may be omitted by using the second communication terminal Tc2 instead of the third communication terminal Tc3, using the first communication terminal Tc1 instead of the fourth communication terminal Tc4, and using the first communication terminal Tc1 and the second communication terminal Tc2 for both transmission and reception.

Next, the parallel connection of the series block 11 will be described. FIG. 8 is an explanatory diagram for explaining the parallel connection of the series block 11. In FIG. 8, the filter 52, inductors L1 and L2, and intermediate connection terminal Ti are omitted.

When multiple series blocks 11 are connected in the Y-axis direction as shown in FIG. 1, the positive output terminal Tpo and negative output terminal Tmo of one side are connected to the positive parallel terminal Tpp and negative parallel terminal Tmp of the other side between the parallel modules 5 adjacent to each other in the Y-axis direction as shown in FIG. 8.

As a result, multiple series blocks 11 are connected in parallel. This makes it possible to increase the current capacity output between the positive output terminal Tpo and the negative output terminal Tmo. In this way, by using the parallelization module 5, the number of series blocks 11 connected in parallel can be easily increased or decreased. As a result, the current capacity of the battery pack system 1 can be easily changed. Therefore, the battery pack system 1 can easily have a current capacity according to the current required for each electrically-driven device, such as an electric vehicle.

In addition, when multiple series blocks 11 are connected in parallel and the unit modules EM of each series block 11 are switched by MMC control or the like, differences in the instantaneous values of the output voltages occur between the series blocks 11. This undesirably results in repeated instantaneous current inputs and outputs between the series blocks 11. Therefore, a filter 52 is provided in the parallelization module 5 to smooth the output voltages of each series block 11, thereby reducing the instantaneous current inputs and outputs between the series blocks 11.

It is not necessary to provide the filter 52 in the parallelization module 5. Instead of providing the filter 52 in the parallelization module 5, the output voltage of each series block 11 may be PWM-controlled by the control unit 51 to output an intermediate voltage of the voltage step, and the voltage step may be made sufficiently small to reduce the output voltage difference between the series blocks 11. This makes it possible to eliminate the need for the filter 52 in the parallelization module 5. However, it is difficult to make the voltage step small when the power storage unit B1 is configured as a battery module combining multiple battery cells. Therefore, it is more preferable to provide the filter 52.

Furthermore, the parallelization module 5 is not limited to an example having a control unit 51. A control unit may be provided outside the parallelization module 5, and multiple serial blocks 11 may be controlled by a single control unit.

The end control unit 41 may also be provided with a control unit 51. When the end control unit 41 is provided with the control unit 51, the control unit 51 may output the first serial signal SS1 to the second communication terminal Tc2 of the battery module 2 located at the second end 32 via the fifth communication terminal Tc5, and the intra-module control unit 23 of each battery module 2 may obtain the control information of its own module from the first serial signal SS1 obtained from the second communication terminal Tc2, and output the remaining control information with the control information deleted as a new first serial signal SS1 from the first communication terminal Tc1.

Similarly, when the end control unit 41 is provided with a control unit 51, the intra-module control unit 23 of each battery module 2 connects the module information related to its own battery module 2 to one end of the second serial signal SS2 obtained from the fourth communication terminal Tc4 and outputs it to the third communication terminal Tc3 as a new second serial signal SS2, and the control unit 51 acquires the second serial signal SS2 received at the sixth communication terminal Tc6.

In addition, the battery pack system 1 may not include a control unit 51, and the control unit 51 may be provided outside the battery pack system 1.

Figure 9 is a schematic perspective view showing another embodiment of the battery pack system 1 shown in Figure 1. The battery pack system 1a shown in Figure 9 differs from the battery pack system 1 in that it has two rows of series blocks 11a and that the first negative terminals Tm1 of the first ends 31 of each series block 11a are short-circuited by a negative bus bar BB1. In addition, the battery pack system 1a does not have a control unit 51, and a control unit 51 provided outside the battery pack system 1a is connected to the first communication terminal Tc1 and the fourth communication terminal Tc4 of the first ends 31 of each series block 11a. This shows an example in which the battery pack system 1a is controlled by the external control unit 51.

The series block 11a does not include a parallelization module 5, and includes an end module 4a instead of the end module 4 in the series block 11. The end module 4a differs from the end module 4 in that it does not include inductors L1, L2 and an intermediate connection terminal Ti, and the third positive terminal Tp3 and the third negative terminal Tm3 are short-circuited.

Figure 10 is a schematic circuit diagram of the battery pack system 1a shown in Figure 9. In Figure 10, the module control unit 23, the end control unit 41, and the circuits related to communication are omitted. According to the battery pack system 1a, by appropriately controlling the connection state of each unit module EM shown in Figure 10, it is possible to output a single-phase AC voltage between the two first positive terminals Tp1 of the first end 31.

Figure 11 is a schematic perspective view showing another embodiment of the battery pack system 1a shown in Figure 9. The battery pack system 1b shown in Figure 11 differs from the battery pack system 1a in that it includes a series block 11b instead of the series block 11a, and in that in addition to the negative bus bar BB1, the first positive terminals Tp1 of the first ends 31 in each series block 11b are short-circuited by a positive bus bar BB2.

Serial block 11b differs from serial block 11a in that it has an end module 4 instead of end module 4a.

Figure 12 is a schematic circuit diagram of the battery pack system 1b shown in Figure 11. In Figure 12, the intra-module control unit 23, the end control unit 41, and the circuits related to communication are omitted. With the battery pack system 1b, as shown in Figure 12, a so-called inverter circuit can be configured. Therefore, by MMC controlling the connection state of each unit module EM, the battery pack system 1b can be operated as an inverter circuit, and a single-phase AC voltage can be output between the two intermediate connection terminals Ti.

Figure 13 is a schematic perspective view showing another embodiment of the battery pack system 1a shown in Figure 9. The battery pack system 1c shown in Figure 13 differs from the battery pack system 1a in that three series blocks 11a are connected in the Y direction, and the first negative terminals Tm1 of the first ends 31 of the three series blocks 11a are short-circuited by the negative bus bar BB1.

Figure 14 is a schematic circuit diagram of the battery pack system 1c shown in Figure 13. In Figure 13, the module control unit 23, the end control unit 41, and the circuits related to communication are omitted. According to the battery pack system 1c, it is possible to output a three-phase AC voltage between the three first positive terminals Tp1 of the first end 31 by appropriately controlling the connection state of each unit module EM shown in Figure 13.

Figure 15 is a schematic perspective view showing another embodiment of the battery pack system 1b shown in Figure 11. The battery pack system 1d shown in Figure 15 differs from the battery pack system 1b in that three series blocks 11b are connected in the Y direction, and that the three first negative terminals Tm1 of the first end 31 are short-circuited by the negative bus bar BB1, and the three first positive terminals Tp1 of the first end 31 are short-circuited by the positive bus bar BB2.

Figure 16 is a schematic circuit diagram of the battery pack system 1d shown in Figure 15. In Figure 15, the intra-module control unit 23, the end control unit 41, and the circuits related to communication are omitted. With the battery pack system 1d, as shown in Figure 16, a so-called three-phase inverter circuit can be configured. Therefore, by MMC controlling the connection state of each unit module EM, the battery pack system 1d can be operated as a three-phase inverter circuit, and a three-phase AC voltage can be output between the three intermediate connection terminals Ti.

Figure 17 is a schematic perspective view showing another embodiment of the battery pack system 1d shown in Figure 15. The battery pack system 1e shown in Figure 17 differs from the battery pack system 1b in that one of the three series blocks 11b in the battery pack system 1b is replaced with a series block 11c.

Series block 11c differs from series block 11a in that battery module 2 is replaced with battery module 2a. Battery module 2a differs from battery module 2 in that battery module B2 is used instead of battery module B1. Battery module B2 has a larger storage capacity and a smaller current rating than battery module B1.

Figure 18 is a schematic circuit diagram of the battery pack system 1e shown in Figure 17. In Figure 18, the module control unit 23, the end control unit 41, and the circuits related to communication are omitted. According to the battery pack system 1e, as shown in Figure 18, a series block 11c including a power storage unit B2 having a larger storage capacity than the power storage unit B1 is connected in parallel to an inverter circuit composed of a plurality of series blocks 11b.

This makes it possible for an inverter circuit using a storage unit B1 with a large current rating to output a high current between multiple intermediate connection terminals Ti, while also allowing energy to be supplied to the inverter circuit from a series block 11c equipped with a storage unit B2 with a large storage capacity. Furthermore, by adding one more series block 11b, it is also possible to accommodate three-phase AC voltage.

Batteries with both a large current rating and a large storage capacity are difficult to obtain. On the other hand, storage unit B1 with a large current rating and a small storage capacity, and storage unit B2 with a small current rating and a large storage capacity are easier to obtain than batteries with both a large current rating and a large storage capacity. Therefore, it is easier to configure a battery pack system 1e that combines storage units B1 and B2 than to use a battery with both a large current rating and a large storage capacity.

1, 1a, 1b, 1c, 1d, 1e Battery pack system 2, 2a Battery module 3 Battery string 4, 4a End module 5 Parallel module 11, 11a, 11b, 11c Series block 21 Positive path section 22 Negative path section 23 Module control section 31 First end section 32 Second end section 41 End control section 42 Current sensor 51 Control section 52 Filters B1, B2 Storage section BB1 Negative bus bar BB2 Positive bus bar C Capacitors D1 to D4 Control information EM Unit modules L, L1, L2 Inductors M1 to M4 Module information SS1 First serial signal (first signal)
SS2 Second serial signal (second signal)
SW1 to SW4 Switching elements T1, T2 Terminal Tc1 First communication terminal Tc2 Second communication terminal Tc3 Third communication terminal Tc4 Fourth communication terminal Tc5 Fifth communication terminal Tc6 Sixth communication terminal Tcc1 First communication connection terminal Tcc2 Second communication connection terminal Ti Intermediate connection terminal Tm1 First negative terminal Tm2 Second negative terminal Tm3 Third negative terminal Tmc1 First negative connection terminal Tmo Negative output terminal Tmp Negative parallel terminal Tp1 First positive terminal Tp2 Second positive terminal Tp3 Third positive terminal Tpc1 First positive connection terminal Tpo Positive output terminal Tpp Positive parallel terminal Vout Output voltage

Claims (16)

a battery string including a plurality of battery modules connected in a row and having a first end and a second end;
an end module coupled to the second end of the battery string;
Each of the battery modules is
a first positive terminal and a first negative terminal provided on the first end side of each of the battery modules;
a second positive terminal and a second negative terminal provided on the second end side of each of the battery modules;
a positive side path portion for passing a current between the first positive terminal and the second positive terminal;
a negative-side path portion for causing a current to flow between the second negative terminal and the first negative terminal,
When the plurality of battery modules are connected to each other, the first positive terminal of one battery module is electrically connected to the second positive terminal of the other battery module, and the first negative terminal of one battery module is electrically connected to the second negative terminal of the other battery module,
At least one of the positive path portion and the negative path portion is
A storage unit that stores electric charge;
a switching circuit that switches a connection state including an adding state in which the power storage unit is added to a current path in the at least one path portion and a removing state in which the power storage unit is removed from the current path,
the end module includes a third positive terminal connected to the second positive terminal and a third negative terminal connected to the second negative terminal of the battery module located at the second end of the battery string,
A battery pack system in which the third positive terminal and the third negative terminal are electrically connected. The positive side path portion is
The power storage unit;
the switching circuit switches a connection state including the connection state in which the power storage unit is connected to the current path of the positive side path portion and the disconnection state in which the power storage unit is disconnected from the current path of the positive side path portion,
The negative path portion is
The power storage unit;
2. The battery pack system according to claim 1, further comprising: a switching circuit that switches a connection state including an insertion state in which the power storage unit is inserted into the current path of the negative side path portion and a removal state in which the power storage unit is removed from the current path of the negative side path portion. Each of the battery modules is
a first communication terminal provided on the first end side of each of the battery modules;
a second communication terminal provided on the second end side of each of the battery modules,
When the plurality of battery modules are connected together, the first communication terminal of one of the battery modules and the second communication terminal of the other battery module are electrically connected to each other between the adjacent battery modules,
The battery pack system according to claim 1 , wherein each of the battery modules further includes an internal module control unit that switches the connection state by the switching circuit in response to control information obtained from the first communication terminal or the second communication terminal. a control unit that outputs a first signal, in which the control information for each of the battery modules is linked in order of linkage of the plurality of battery modules in the battery string, to the first communication terminal of the battery module located at the first end,
The battery pack system of claim 3, wherein the module control unit acquires the control information linked to one end of the first signal obtained from the first communication terminal in its own battery module as the control information for itself, and outputs the remaining signal obtained by deleting the control information for itself from the first signal as a new first signal to the second communication terminal in its own battery module. Each of the battery modules is
a third communication terminal provided on the second end side of each of the battery modules;
a fourth communication terminal provided on the first end side of each of the battery modules,
5. The battery pack system of claim 4, wherein the module control unit links module information regarding its own battery module to one end of a second signal obtained from the third communication terminal in its own battery module and outputs the resulting new second signal to the fourth communication terminal in its own battery module. The battery pack system according to claim 4, wherein the module control unit connects module information related to its own battery module to one end of the second signal obtained from the second communication terminal in its own battery module, and outputs the resulting new second signal to the first communication terminal in its own battery module. a control unit that outputs a first signal, in which the control information for each of the battery modules is linked in order of linkage of the plurality of battery modules in the battery string, to the second communication terminal of the battery module located at the second end,
The battery pack system of claim 3, wherein the module control unit acquires the control information linked to one end of the first signal obtained from the second communication terminal in its own battery module as the control information for itself, and outputs the remaining signal obtained by deleting the control information for itself from the first signal as a new first signal to the first communication terminal in its own battery module. Each of the battery modules is
a third communication terminal provided on the second end side of each of the battery modules;
a fourth communication terminal provided on the first end side of each of the battery modules,
8. The battery pack system of claim 7, wherein the module control unit links module information regarding its own battery module to one end of a second signal obtained from the fourth communication terminal in its own battery module and outputs the resulting new second signal to the third communication terminal in its own battery module. The battery pack system according to claim 7, wherein the module control unit connects module information related to the battery module to one end of the second signal obtained from the first communication terminal of the battery module and outputs the resulting new second signal to the second communication terminal of the battery module. The end module comprises:
an inductor interposed between the third positive terminal and the third negative terminal;
The battery pack system according to claim 2 , further comprising an intermediate connection terminal electrically connected to a midpoint of the inductor. A battery pack according to the present invention includes a battery string,
a parallelization module for connecting the plurality of battery strings in parallel;
the parallelization module is provided for each of the battery strings,
a first positive connection terminal connected to the first positive terminal of the battery module located at the first end;
a first negative connection terminal connected to the first negative terminal of the battery module located at the first end;
a positive output terminal and a positive parallel terminal electrically connected to the first positive connection terminal;
a negative output terminal and a negative parallel terminal electrically connected to the first negative connection terminal;
the first positive connection terminal and the first negative connection terminal are located on an outer surface of the parallelization module in a direction perpendicular to the row direction of the battery row;
The battery pack system according to claim 1 , wherein the positive parallel terminal and the negative parallel terminal are located on an outer surface of the paralleling module opposite to the first positive connection terminal and the first negative connection terminal. The battery pack system of claim 11, wherein the paralleling module further includes a filter that smoothes the voltage obtained from the first positive connection terminal and the first negative connection terminal. Each of the battery modules includes a plurality of the power storage units,
13. The battery pack system according to claim 1, wherein the switching circuit switches the connection state for each of the power storage units. A battery module used in a battery pack system according to any one of claims 1 to 12. An end module used in a battery pack system according to any one of claims 1 to 12. A parallelization module used in the battery pack system according to claim 11 or 12.

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