WO2024057770A1

WO2024057770A1 - Power storage device

Info

Publication number: WO2024057770A1
Application number: PCT/JP2023/028591
Authority: WO
Inventors: 竜一伊藤; 清浩藤田
Original assignee: 株式会社Ｇｓユアサ
Priority date: 2022-09-16
Filing date: 2023-08-04
Publication date: 2024-03-21
Also published as: JP2024042861A

Abstract

A power storage device 20 comprises: a cell 31; a switching circuit 50 that is located on the current path of the cell 31; and a control device 100. The switching circuit 50 is a circuit for switching the output impedance Z of the power storage device 20. The control device 100 uses the switching circuit 50 to switch the output impedance of the power storage device 20.

Description

Power storage device

The present invention relates to a technique for controlling the output impedance of a power storage device.

Power storage devices installed in automobiles and the like have current interrupting devices such as FETs. When an abnormality such as overdischarge or overcharging is detected, the power storage device can be protected by opening the current interrupting device and interrupting the current. Patent Document 1 is a document that discloses this type of technology.

WO2019/111872 publication

The required output performance of power storage devices for vehicles differs depending on the purpose, usage situation, etc. For example, while the vehicle is parked, it is only necessary to output a small current, but when the vehicle is running or other conditions other than parking, it is necessary to charge and discharge a larger current than when the vehicle is parked. Conventionally, since the output impedance of a power storage device is fixed, the structure has been such that the output performance cannot be changed. Similar problems have also occurred in power storage devices other than those for vehicles.

An object of the present invention is to provide a power storage device with an output impedance switching function.

The power storage device includes a cell, a switching circuit located on a current path of the cell, and a control device. The switching circuit is a circuit that switches the output impedance of the power storage device, and the control device uses the switching circuit to switch the output impedance of the power storage device according to predetermined conditions. The predetermined conditions include, for example, the purpose of the power storage device, usage status, actual capacity, internal resistance, and state of deterioration.

In a power storage device, the output performance of the power storage device can be changed by switching the output impedance.

car side view Perspective view of battery Exploded perspective view of battery Block diagram showing the electrical configuration of the battery Circuit diagram of switching circuit Diagram showing details of switch circuit Battery schematic diagram Chart summarizing battery output impedance and usage Flowchart of output impedance switching control Flowchart of output impedance switching control Circuit diagram of switching circuit

(Summary of this embodiment)
(1) A power storage device according to an embodiment of the present invention includes a cell, a switching circuit located on a current path of the cell, and a control device. The switching circuit is a circuit that switches the output impedance of the power storage device, and the control device uses the switching circuit to switch the output impedance of the power storage device according to predetermined conditions. The predetermined conditions include, for example, the purpose of the power storage device, the usage status, the size of the actual capacity, and the like.

According to the power storage device according to an embodiment of the present invention, by switching the output impedance according to the predetermined conditions, it is possible to exhibit output performance suitable for the predetermined conditions. For example, in the case of a small current application, the current of the power storage device can be reduced by switching the output impedance to a large value. In the case of large current applications, switching the output impedance to a small value makes it easier for the current to flow, making it easier to ensure a sufficient amount of current.

(2) In the power storage device according to (1) above, the control device acquires information on the use or usage status of the power storage device through communication with a vehicle, and depending on the acquired information, It is also possible to switch the output impedance of the

With this configuration, by switching the output impedance according to the purpose and usage situation of the power storage device, the power storage device can exhibit output performance according to the purpose and usage situation. Another advantage is that the output performance can be changed each time the usage status of the power storage device installed in the vehicle changes.

(3) In the power storage device according to (1) above, the control device acquires information on the type of vehicle through communication with the vehicle, and adjusts the output impedance of the power storage device according to the acquired information. You may switch.

The maximum current required for the power storage device may differ depending on the type of vehicle. For example, a large vehicle requires a larger maximum current than a light vehicle. With this configuration, it is possible to supply a maximum current from the power storage device to the vehicle, with a magnitude depending on the type of vehicle. Therefore, there is an advantage that the power storage device can be used universally in different types of vehicles. The type of vehicle is not limited to light vehicles or large vehicles, and may be of any type as long as it classifies vehicles with different maximum current requirements.

(4) In the power storage device according to (1) above, the control device includes a storage unit that stores information on the size of the actual capacity of the power storage device or information related to the usage, and The output impedance of the power storage device may be switched depending on the actual capacity of the device or information regarding the usage.

With this configuration, the output impedance of the power storage device can be switched depending on the actual capacity of the power storage device and the application. Therefore, the power storage device can exhibit output performance depending on the size of the actual capacity and the purpose. This configuration has the advantage that the power storage device can autonomously change its output impedance even when there is no communication function with a host device such as a vehicle.

(5) In the power storage device according to (1) above, the control device may switch the output impedance of the power storage device depending on the internal resistance or deterioration state of the cell.

According to this configuration, by switching the output impedance according to the internal resistance of the cell, it is easy to maintain the total resistance of the power storage device constant regardless of the passage of time after manufacture or the increase in internal resistance due to long-term use. Become. Therefore, heat generation can be suppressed while maintaining the ability to supply power to the load. A configuration in which the output impedance of the power storage device is switched depending on the state of deterioration has a similar effect.

(6) In the power storage device according to any one of (1) to (5) above, the switching circuit is a plurality of energizing circuits connected in parallel, and the plurality of energizing circuits have different line resistances. , the control device may switch the output impedance of the power storage device by selecting or combining the energizing circuits.

With this configuration, the output impedance of the power storage device can be switched by selecting or combining the energizing circuits. Furthermore, since the current can be cut off by turning off all current-carrying circuits, it can also be used as a protection device for power storage devices.

<Embodiment 1>
1. Description of Battery FIG. 1 is a side view of an automobile, FIG. 2 is a perspective view of the battery, FIG. 3 is an exploded perspective view of the battery, and FIG. 4 is a block diagram showing the electrical configuration of the battery. In FIG. 1, only the automobile 1 and the battery 20 are shown, and other parts constituting the automobile are omitted.

As shown in FIG. 1, an automobile (an example of a vehicle) 1 includes a battery 20 that is a power storage device. As shown in FIG. 2, the battery 20 has a block-shaped battery case 21, and the battery case 21 houses a battery pack 30 made up of a plurality of cells 31, a circuit board 120, and the like.

In the following description, when referring to FIGS. 2 and 3, the vertical direction of the battery case 21 when the battery case 21 is placed horizontally without tilting with respect to the installation surface is the Y direction, and the long side of the battery case 21 is The following description will be made assuming that the direction along the direction is the X direction and the depth direction of the battery case 21 is the Z direction.

As shown in FIG. 3, the battery case 21 includes a box-shaped case body 23 that opens upward, a positioning member 24 that positions the plurality of cells 31, and an inner lid 25 that is attached to the top of the case body 23. It is configured to include an upper lid 29 attached to the upper part of the inner lid 25. Inside the case main body 23, a plurality of cell chambers 23A in which each cell 31 is individually housed are provided side by side in the X direction.

As shown in FIG. 3, the positioning member 24 has a plurality of bus bars 24A arranged on its upper surface, and the positioning member 24 is arranged above the plurality of cells 31 arranged in the case body 23. Therefore, the plurality of cells 31 are positioned and connected in series by the plurality of bus bars 24A.

As shown in FIG. 3, the inner lid 25 has a substantially rectangular shape in a plan view, and a pair of

external terminals

22P and 22N to which harness terminals (not shown) are connected are provided at both ends in the X direction. The pair of

external terminals

22P and 22N are made of metal such as lead alloy, for example, and 22P is for the positive electrode and 22N is for the negative electrode.

As shown in FIG. 3, a circuit board 120 is arranged on the upper surface of the inner lid 25, and the upper lid 29 closes the upper part of the circuit board 120.

FIG. 4 is a block diagram showing the electrical configuration of the battery 20. The battery 20 includes a battery pack 30, a voltage measurement section 41, a current measurement section 43, a temperature sensor 45, a switching circuit 50, and a management device 100.

There are, for example, four cells 31 of the assembled battery 30 (see FIG. 2), and the four cells 31 are connected in series. The cell is not limited to a prismatic cell, and may be a cylindrical cell or a pouch cell having a laminate film case. The cell 31 is, for example, a lithium ion secondary battery cell.

The assembled battery 30, current measurement section 43, and switching circuit 50 are connected in series via a power line 35P and a power line 35N.

As shown in FIG. 4, the power line 35P connects the positive external terminal 22P and the positive electrode of the assembled battery 30. The power line 35N connects the negative external terminal 22N and the negative electrode of the assembled battery 30. The

external terminals

22P and 22N are terminals for connection to the automobile 10, and can be electrically connected to an on-vehicle auxiliary device 15 and a vehicle ECU (Electronic Control Unit) 16 via the

external terminals

22P and 22N.

The voltage measurement unit 41 can measure the cell voltage Vs of each cell 31A to 31D and the total voltage of the assembled battery 30.

The current measurement unit 43 is provided on the negative power line 35N. The current measuring section 43 may be a shunt resistor. The resistive current measuring section 43 can measure the current I of the assembled battery 30 based on the voltage across the current measuring section 43 . Alternatively, the current measuring section 43 may be a magnetic sensor.

The temperature sensor 45 is attached to the assembled battery 30 and detects the temperature of the assembled battery 30 or its surroundings.

The switching circuit 50 is mounted on the circuit board 120 and is provided on the positive power line 35P. The switching circuit 50 is a circuit that switches the output impedance Z of the battery 20. Details of the switching circuit 50 will be described later.

The management device 100 is mounted on a circuit board 120, and includes a CPU 101, a storage section 103, and a communication section 105, as shown in FIG. The management device 100 corresponds to the "control device" of the present invention. The storage unit 103 stores information for specifying the purpose of the battery 50. For example, it is information on the part number of the battery 50.

The management device 100 monitors the state of the battery 20 based on the outputs of the voltage measurement unit 41, current measurement unit 43, and temperature sensor 45. That is, the management device 100 monitors the cell voltage Vs of each cell 31, the temperature of the assembled battery 30, the current I, and the total voltage V.

The communication unit 105 is for communication connection with the vehicle ECU 16. Management device 100 can be connected to vehicle ECU 16 via communication section 105, connector 106, and communication line 107.

The storage unit 103 stores a battery 20 monitoring program, an output impedance Z switching program, and data necessary for executing these programs. The storage unit 103 further stores information (for example, a part number) for specifying the use of the battery 20.

The vehicle ECU 16 can determine the usage of the battery 20 by reading out information for identifying the usage (for example, a part number) from the battery 20, such as when starting communication with the battery 20. For example, if you have a reference table that stores part numbers and applications in association with each other, it is possible to identify the application from the part number. The battery 20 is used for auxiliary equipment, engine starting, and the like.

The program may be stored in a recording medium such as a CD-ROM and used, transferred, lent, etc. The program may be distributed using telecommunications lines.

2. Output Impedance Switching Control FIG. 5 is a circuit diagram of the switching circuit 50. The switching circuit 50 is a circuit that switches the output impedance Z of the battery 20. In this embodiment, the switching circuit 50 has three energizing circuits 51A to 51C connected in parallel.

The first energizing circuit 51A to the third energizing circuit 51C each have switch circuits 53A to 53C, and by turning off the switch circuits 53A to 53C, each of the energizing circuits 51A to 51C can be cut off. By turning on the circuits 53A to 53C, each of the energizing circuits 51A to 51C is turned on, allowing current to flow.

The switch circuits 53A to 53C can be configured, for example, as shown in FIG. 6, by two FETs (field effect transistors) 54 and 55 connected back to back.

As shown in FIG. 5, the first energizing circuit 51A includes only a switch circuit 53A and does not have a current limiting element. The second energizing circuit 51B and the third energizing circuit 51C include current limiting

elements

57 and 58 in addition to switch

circuits

53B and 53C.

The current limiting element 57 and the current limiting element 58 are resistors. The two current limiting

elements

57 and 58 have different resistance values, and the current limiting element 58 of the third energizing circuit 51C has a larger resistance value than the current limiting element 57 of the second energizing circuit 51B.

In other words, in the three energizing circuits 51A to 51B, the resistance values of the lines LA to LC that connect the positive electrode of the assembled battery 30 and the positive external terminal 22P are different. The resistance values of the lines LA to LC increase in the order of the first energizing circuit 51A, the second energizing circuit 51B, and the third energizing circuit 51C, and the resistance value of the line LC of the third energizing circuit 51C increases. It is the largest. The resistance value of the lines LA to LC is the sum of the resistance of the lines themselves and the resistance of the current limiting element provided on the lines.

(Size relationship of line resistance)
RA<RB<RC
RA: Resistance value of the line LA of the first energizing circuit 51A RB: Resistance value of the line LB of the second energizing circuit 51B RC: Resistance value of the line LC of the third energizing circuit 51C

From the above, the output impedance Z of the battery 20 can be switched by using the first energizing circuit 51A to the third energizing circuit 51C selectively or in combination.

FIG. 7 is a simplified equivalent circuit of the battery 20, in which VC indicates the internal electromotive force of the assembled battery 30, and Z indicates the output impedance. The output impedance Z is the impedance when the battery 20 is viewed from the

output terminals

22P and 22N side (when the battery 20 is viewed from the direction A in FIG. 7).

For example, as shown in FIG. 8, when the first energizing circuit 51A with a small line resistance is selected, the output impedance Z of the battery 20 is small.

On the other hand, when the second energizing circuit 51B with a medium line resistance is selected, the output impedance Z of the battery 20 is medium, and when the third energizing circuit 51C with a high line resistance is selected, the output impedance Z of the battery 20 is large. .

When the output impedance Z is small, current flows easily and charging/discharging of a large current is possible, so it is suitable for large current applications. When the output impedance Z is large, the current is limited, so it is suitable for small current applications.

FIG. 9 is a flowchart of output impedance Z switching control. The switching control of the output impedance Z is composed of four steps S10 to S40, and is executed using, for example, the start of communication with the vehicle ECU 16 as the battery 20 is installed in the vehicle as a trigger.

When the switching control of the output impedance Z starts, the management device 100 first accesses the vehicle ECU 16 and acquires information on the usage of the battery 20 from the vehicle EUC 16. The battery 20 is used for, for example, auxiliary equipment or engine starting.

For engine starting, a cranking current of several hundred A to 1000 A is discharged, so it is a large current application. The battery for auxiliary equipment is used for medium current as it charges and discharges from several tens of A to 500 A.

When the battery 20 is used for auxiliary equipment (medium current), the management device 100 shuts off the first energization circuit 51A, and turns on the second energization circuit 51B and the third energization circuit 51C. Thereby, the output impedance Z of the battery 20 used for auxiliary equipment can be switched to "medium" (S30).

When the battery 20 is used for engine starting (large current), the management device 100 controls all of the first energizing circuit 51A to the third energizing circuit 51C to be ON. Thereby, the output impedance Z of the battery 20 used for engine starting can be switched to "low" (S40).

4. Effects According to this configuration, the output impedance Z of the battery 20 can be switched depending on the use of the battery 20. Therefore, the battery 20 can exhibit output performance depending on the application.

For example, for engine starting, by switching the output impedance Z to "small", current flows more easily than when the output impedance Z is "medium" or "large". Therefore, it is possible to discharge sufficient current necessary for starting the engine, and the startability of the engine can be ensured.

For auxiliary equipment, by switching the output impedance Z to "medium", the current will flow more easily than when the output impedance Z is "small". Therefore, Joule heat can be reduced, and heat generation of the battery 20 can be suppressed.

In commonly used batteries, when a short circuit current exceeding a threshold flows due to an external short circuit or the like, the battery 20 is protected by cutting off the current using a relay or the like.

However, the battery 20 cannot be used in a state where the current is cut off, and a special operation may be required and time consuming to release the current cutoff. Further, since the assembled battery 30 and the external terminal 22 are separated, there is also the problem that the voltage of the battery 20 cannot be measured.

In this configuration, by switching the output impedance Z to "medium" for the auxiliary equipment, it becomes more difficult for current to flow than when the output impedance Z is controlled to "small". Therefore, even if an external short circuit or the like occurs, the short circuit current is less likely to exceed the threshold value, so the chances of interrupting the current can be reduced. Therefore, the above problems can be solved.

Also in the battery 20 described in this embodiment, it is possible to cut off the current exceeding the threshold value by controlling all of the energizing circuits 51A to 51C to OFF.

<Embodiment 2>
The second embodiment is different from the first embodiment in the switching control of the output impedance Z. FIG. 10 is a flowchart of output impedance Z switching control in the second embodiment.

The switching control of the output impedance Z is composed of four steps S15 to S45, and is executed at a predetermined period, for example, after the battery 20 is installed in the vehicle. In this example, it is assumed that the battery 20 is for auxiliary equipment.

When the switching control of the output impedance Z starts, the management device 100 first accesses the vehicle ECU 16 and acquires information regarding the state of the automobile 10 from the vehicle EUC 16. Specifically, information is obtained as to whether the automobile 10 is parked or in any other state.

When the automobile 10 equipped with the battery 20 is parked (when the battery 20 is used in the parked automobile 10), the management device 100 turns off the first energizing circuit 51A and the second energizing circuit 51B, and turns off the first energizing circuit 51A and the second energizing circuit 51B. 3 energization circuit 51C is controlled to be ON.

As a result, when the automobile 10 equipped with the battery 20 is parked, the output impedance Z of the battery 20 can be switched to "high" (S35).

When the vehicle 10 equipped with the battery 20 is in a state other than parked (when the battery 20 is used in a vehicle that is running, etc.), the management device 100 shuts off the first energizing circuit 51A and disconnects the second energizing circuit 51B. and the third energizing circuit 51C is controlled to be ON.

As a result, when the automobile 10 equipped with the battery 20 is in a state other than parking, the output impedance Z of the battery 20 can be switched to "medium" (S45).

With this configuration, the output impedance Z of the battery 20 can be switched depending on the usage status of the battery 20. Therefore, the battery 20 can exhibit output performance depending on the usage situation.

Specifically, when the battery 20 is used in a parked car 10 with little charging/discharging, the output current of the battery 20 can be suppressed by switching the output impedance to "high". In addition, when used in a running car that discharges to auxiliary equipment or charges from an alternator, by switching the output impedance to "medium", the current suitable for discharging or charging the auxiliary equipment is charged and discharged. I can do it.

<Embodiment 3>
In the first embodiment, information on the use of the battery 20 is acquired through communication with the vehicle ECU 16, and the output impedance Z of the battery 20 is switched. In the second embodiment, information on the usage status of the battery 20 is acquired through communication with the vehicle ECU 16, and the output impedance Z of the battery 20 is switched.

In the third embodiment, as shown in FIG. 11, data on the actual capacity [Ah] of the battery 20 is written and stored in the storage unit 103 during the production process of the battery 20. In this case, the storage unit 103 is preferably nonvolatile. The actual capacity is the amount of electricity that can be extracted from the battery 20, and is also referred to as full charge capacity [Ah].

After startup, the control device 100 reads data on the actual capacity [Ah] from the storage unit 103 and switches the output impedance Z of the battery 20.

For example, for a small capacity battery 20, the output impedance Z is switched to "large", and for a medium capacity battery 20, the output impedance Z is switched to "medium". Furthermore, the output impedance Z of the large capacity battery 20 is switched to "small".

With this configuration, the output impedance Z of the battery 20 can be switched depending on the actual capacity. Therefore, the battery 20 can exhibit output performance that corresponds to the actual capacity. This configuration has the advantage that the battery 20 can autonomously change the output impedance Z even when there is no communication function with a host device such as an automobile.

<Other embodiments>
The present invention is not limited to the embodiments described above and illustrated in the drawings; for example, the following embodiments are also included within the technical scope of the present invention.

(1) The cell (repetitively chargeable/dischargeable electricity storage cell) 31 is not limited to a lithium ion secondary battery cell, but may be any other nonaqueous electrolyte secondary battery cell. A capacitor can also be used instead of the secondary battery cell 31.

(2) In the first to third embodiments above, the vehicle battery 20 was explained. In the case of the third embodiment, the battery 20 is not limited to use in a vehicle, and may be used for other purposes. For example, it may be used for stationary applications such as a power storage device for absorbing fluctuations in a distributed power generation system or a UPS (uninterruptible power supply).

(3) In the first embodiment described above, the vehicle ECU 16 determines the use of the battery 20 based on the part number of the battery 20. The present invention is not limited to this, and the purpose of the battery 20 may be determined based on the actual capacity of the battery 20. In other words, as illustrated in the third embodiment, if data on the actual capacity of the battery 20 is written in the storage unit 103 during the manufacturing process, the data on the actual capacity can be read out from the battery 20 at the start of communication. , the vehicle ECU 16 can also determine the use of the battery 20.

(4) In the first embodiment described above, the purpose of the battery 20 is determined by the vehicle ECU 16, but if vehicle information (vehicle code for identifying the vehicle, etc.) is acquired through communication with the vehicle, the purpose of the battery 20 can be determined by the vehicle ECU 16. It is also possible to make the determination using the battery 20. For example, if a reference table that associates vehicle information and battery usage is stored in the storage unit 103 of the battery 20, by transmitting the vehicle information from the vehicle ECU 16 to the control device 100, the control device 100 can 20 uses can be determined.

(5) In the second embodiment described above, when the battery 20 is used in the parked automobile 10, the output impedance Z of the battery 20 is switched to "high". In addition to this, for example, the output impedance Z of the battery 20 may be switched to "high" before the battery 20 is mounted on the vehicle 10 (during battery transportation, etc.) or when it is removed from the vehicle 10. Attachment and detachment from the automobile 10 can be determined based on the communication state with the vehicle ECU 16. For example, if there has been no communication with the vehicle ECU 16, it can be determined that this is before the vehicle 10 is installed. If there is no communication with the vehicle ECU 16 for a predetermined period of time or more after the communication with the vehicle ECU 16 is started, it can be determined that the battery 20 has been removed from the vehicle 10.

(6) In the first to third embodiments described above, a plurality of energizing circuits 51A to 51C connected in parallel were shown as an example of the switching circuit 50 that switches the output impedance Z. The switching circuit 50 only needs to be able to switch the output impedance Z of the battery 20, and is not limited to the circuit configuration of the embodiment. For example, a circuit using a variable resistor may be used.

(7) In the first to third embodiments described above, the switch circuits 53A to 53C are composed of two FETs. The switch circuits 53A to 53C may have other configurations, such as a single switch, as long as they can turn on and off the current.

(8) In the third embodiment, the data of the actual capacity [Ah] of the battery 20 is written and stored in the storage unit 103 during the production process of the battery 20. Then, when the control device 100 was started, the actual capacity data was read from the storage unit 103 and the output impedance Z was switched. In addition to the actual capacity data, data on the usage of the battery 20 may be written and stored in the storage unit 103 during the production process. Then, when the control device 100 is activated, the output impedance Z may be switched by reading the application data from the storage unit 103.

(9) In the first to third embodiments described above, the switching circuit 51 is composed of three energizing circuits 51A to 51C connected in parallel. The three energizing circuits 51A to 51C can be used not only for switching the output impedance Z but also as a backup in the event of a failure (redundancy). For example, if the energizing circuit 51A has an OPEN failure during use, charging and discharging can be continued by using the other energizing

circuits

51B and 51C.

(10) In the first embodiment described above, the output impedance Z was switched depending on the use of the battery 20. In the second embodiment, the output impedance Z is switched depending on the usage status of the battery 20. The output impedance Z of the battery 20 may be switched depending on the type of the automobile 10 as well as the application or usage status of the battery 20. For example, the control device 100 for the battery 20 acquires information on the type of automobile 10 in which the battery 20 is mounted through communication with the vehicle ECU 16. If the vehicle 10 is a type of vehicle that requires a large maximum current, such as a large vehicle, the control device 100 switches the output impedance Z of the battery 20 to a small value. If the vehicle 10 is a type of vehicle that requires a small maximum current, such as a small vehicle, the output impedance Z of the battery 20 is switched to high. With this function, the battery 20 can be used universally (common use) between different types of automobiles.

(11) In the first embodiment described above, the output impedance Z was switched depending on the use of the battery 20. In the second embodiment, the output impedance Z is switched depending on the usage status of the battery 20. The output impedance Z of the battery 20 may be switched depending on the internal resistance of the assembled battery 30, not only the purpose and usage status of the battery 20. For example, by changing the output impedance Z (from large to small) in accordance with the change in internal resistance of the assembled battery 30 (from small to large), the output impedance Z can be changed (from large to small) in response to the change in internal resistance of the assembled battery 30, regardless of the increase in internal resistance due to the passage of time after manufacture or long-term use. First, it becomes easier to keep the total resistance of the battery 20 constant. Therefore, heat generation can be suppressed while maintaining the ability to supply power to the load. The internal resistance of the assembled battery 30 can be calculated from the measured values of the terminal voltage and current of the battery 20. Instead of the internal resistance, the output impedance of the battery 20 may be switched depending on the state of deterioration of the battery 20. In other words, as the battery 20 deteriorates, by lowering the output impedance Z of the battery 20, it is possible to compensate for the decrease in output performance that accompanies the deterioration. The deterioration state of the battery 20 can be determined, for example, using as an index the maintenance rate of the actual capacity (full charge capacity) based on the initial value at the time of manufacture.

10 Automobile 20 Battery 31 Cell 50 Switching circuit 51A to 51C Energizing circuit 100 Management device (control device)

Claims

A power storage device,
cell and
a switching circuit located on the current path of the cell;
comprising a control device;
The switching circuit is a circuit that switches the output impedance of the power storage device,
The control device is a power storage device that switches output impedance of the power storage device using the switching circuit according to a predetermined condition.
The power storage device for a vehicle according to claim 1,
A power storage device, wherein the control device acquires information on the use or usage status of the power storage device through communication with a vehicle, and switches output impedance of the power storage device according to the acquired information.
The power storage device for a vehicle according to claim 1,
The control device is a power storage device in which the control device acquires information on the type of vehicle through communication with the vehicle, and switches the output impedance of the power storage device according to the acquired information.
The power storage device according to claim 1 ,
The control device includes a memory unit that stores information on the actual capacity of the power storage device or information on its intended use, and switches the output impedance of the power storage device in accordance with the information on the actual capacity of the power storage device or its intended use stored in the memory unit.
The power storage device according to claim 1,
The control device is a power storage device that switches output impedance of the power storage device according to an internal resistance or a deterioration state of the cell.
The power storage device according to claim 1 or claim 2,
The switching circuit is a plurality of energizing circuits connected in parallel,
Multiple energized circuits have different line resistances,
In the power storage device, the control device switches output impedance of the power storage device by selecting or combining the energizing circuits.