JP2014124064A - Power storage system, and cartridge - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power storage system capable of improving efficiency of charge or discharge by simultaneously charging or discharging a plurality of cartridges, while preventing occurrence of cross flow between respective cartridges.SOLUTION: A power storage system 6 comprises: a plurality of cartridges 100_1 to 100_4 which are connected in parallel and are composed of a plurality of connected cells; and cross current prevention circuits 65_1 to 65_4 for restricting current through each of the cartridges 100_1 to 100_4 in one direction. The power storage system 6 simultaneously charges the plurality of cartridges 100_1 to 100_4 connected in parallel by converting commercial voltage to direct voltage, or simultaneously discharges the plurality of cartridges 100_1 to 100_4 connected in parallel to output the commercial voltage.

Description

  The present invention relates to a power storage system and a cartridge.

  Demand for storage batteries is expected to grow mainly in electric vehicles. On the other hand, it is also attracting attention for stationary use, and has been highlighted as an energy-saving device that promotes the securing of power in an emergency, leveled power storage accompanying the introduction of renewable energy, and efficient use of energy. The use of storage batteries such as V2H (Vehicle to Home) and storage battery recycling is wide-ranging, and the future storage battery business is expected to attract attention.

In the stationary storage battery that is currently devised, all battery packs are fixed to the system by welding or the like. On the other hand, as a method for effectively utilizing a large-sized secondary battery, there is a method of making the battery into a cartridge. The term “cartridge” as used herein means that the battery is replaceable or easily replaceable and can be transported. For example, by using a storage battery for a housing as a cartridge, it can be used as an extender for an electric vehicle whose cruising distance varies greatly depending on the running state, or when it is used for a bicycle, the battery charging time can be omitted, improving convenience (for example, prior art Reference 1).
In addition, when the amount of electric power used in the home changes, the capacity can be easily increased, and it is not necessary to install a new system, so that high economic efficiency can be obtained. Furthermore, it can be applied to large-scale storage batteries such as community levels and factories, and since only a deteriorated battery pack can be replaced, the system can be very easily updated.

Japanese Patent Laid-Open No. 2001-016706

  However, in the above-described technology, a problem is a housing / battery management system. Conventionally, in residential applications, battery packs are usually fixed by welding, but in order to make them into cartridges, they are absolutely removable. That is, in order to realize a cartridge, it is important that the power storage system and the cartridge are securely and safely connected. Further, even in a situation where one of the plurality of cartridges is not connected, it is essential to supply electric power or charge the cartridge as the power storage system.

  Furthermore, even if batteries with different charge capacities enter the power storage system, they must be managed throughout. When conventional battery packs are connected in series, if the charge capacity of a cartridge with a large charge capacity is 100 and the charge capacity of a cartridge with a small charge capacity is 90, the total battery capacity is not 100 + 90 but 90 × 2 = 180. turn into. That is, the overall voltage is reduced to the lowest cartridge voltage, and the energy capacity that can be extracted is reduced. In parallel, for example, an inrush current (also referred to as a cross current) corresponding to a potential difference may flow from a cartridge having a high voltage to a cartridge having a low unit voltage.

  In order to solve such a problem, it is conceivable to perform a process for equalizing (leveling) the capacity of the cartridges. However, when such prescription is performed, there is a problem that processing of the power storage system becomes complicated.

  On the other hand, as an added value, in order to promote the effective utilization of power from solar cells and grids, it is possible to connect a power storage system to a LAN, obtain weather forecasts, and build an energy total management system that takes into account lifestyle patterns desirable.

  The present invention has been made in view of such circumstances, and an object thereof is to provide a power storage system in which a battery pack is made into a cartridge and electric power can be effectively used. It is another object of the present invention to provide a power storage system that can sufficiently extract the energy of individual cartridges while eliminating the process of energy balance between cartridges by leveling.

In order to solve the above-described problem, a power storage system according to the present invention has a cross current in which a plurality of cartridges each including a plurality of connected cells are connected in parallel, and the current for each of the cartridges is limited to one direction of discharging or charging. A prevention circuit is provided, and a plurality of cartridges connected in parallel are converted into a DC voltage and charged simultaneously, or a plurality of cartridges connected in parallel are discharged simultaneously to output a commercial voltage. To do.
According to this configuration, it is possible to discharge or charge a plurality of cartridges at the same time to increase the efficiency of discharging or charging, and even if a plurality of cartridges are discharged or charged at the same time, cross current is generated. Can be prevented.

Furthermore, the present invention provides the above-described power storage system, which is provided in common for a plurality of cartridges connected in parallel, and simultaneously converts a plurality of cartridges connected in parallel to a commercial voltage into a DC voltage and charges them simultaneously. A power conditioner that simultaneously discharges a plurality of cartridges connected in parallel and outputs a commercial voltage; and a cross-current prevention circuit including a diode and a switch circuit that limits a current to each of the cartridges in one direction of discharge or charging. And a control circuit for controlling conduction or non-conduction of the switch circuits constituting the plurality of cross current prevention circuits.
According to this configuration, it is possible to discharge or charge a plurality of cartridges at the same time to increase the efficiency of discharging or charging, and even if a plurality of cartridges are discharged or charged at the same time, cross current is generated. Can be prevented.

The present invention is the above-described power storage system, wherein the cross current prevention circuit includes a first diode and a first switch circuit connected in series that form a current path only in the discharge direction with respect to each of the cartridges, It includes a second diode and a second switch circuit connected in series which form a current path only in the charging direction for each of them.
According to this configuration, it is possible to prevent a cross current between the cartridges by limiting the current for each of the cartridges to one direction of the discharging direction or the charging direction.

Further, the present invention is the above-described power storage system, wherein the control circuit receives a discharge instruction signal instructing discharge from the power storage system in a discharge direction with respect to a plurality of cartridges connected in parallel. Only the first switch circuit that forms the current path is made conductive at the same time, and the commercial voltage is output until the sustain voltage of the plurality of cartridges becomes the first voltage.
According to this configuration, when a plurality of cartridges are discharged at the same time, it is possible to prevent the occurrence of cross current caused by the difference between the terminal voltages of the cartridges.

In addition, the present invention is the above-described power storage system, and when the control circuit receives a charge instruction signal instructing charging of the power storage system, a plurality of cartridges connected in parallel are charged in the charging direction. Only the second switch circuit that forms the current path is made conductive at the same time, and charging is performed according to the commercial voltage until the sustain voltage of the cartridge becomes the second voltage.
According to this configuration, when a plurality of cartridges are charged at the same time, it is possible to prevent the occurrence of cross current caused by the difference between the terminal voltages of the cartridges.

In addition, the present invention is the above-described power storage system, wherein the control circuit is a case where a discharge instruction signal is input, and a user pulls out one of a plurality of cartridges connected in parallel. When a cartridge extraction signal indicating that the cartridge is intended is input, if the cartridge is being discharged, the first switch circuit that forms a current path only in the discharge direction is made non-conductive with respect to the cartridge. Thus, a signal indicating that the cartridge can be extracted is output.
According to this configuration, during discharge from the cartridge of the power storage system, the user can safely pull out the cartridge intended to be removed.

Further, the present invention is the above-described power storage system, wherein the control circuit is a case where a charging instruction signal is input, and the user pulls out any one of the cartridges connected in parallel. When a cartridge removal signal indicating that the cartridge is intended is input, if the cartridge is being charged, the second switch circuit that forms a current path only in the charging direction is made non-conductive with respect to the cartridge. Thus, a signal indicating that the cartridge can be extracted is output.
According to this configuration, during charging of the cartridge of the power storage system, the user can safely pull out the cartridge intended to be removed.

Further, the present invention is characterized in that a cover is provided on the power storage system and the cartridge side for the connection portion between the power storage system and the cartridge, and when the cartridge is fitted into the power storage system, the connection portion is exposed to form an electrical connection. And
According to this configuration, the power storage system and the cartridge can be reliably and safely connected.

  In addition, the present invention is characterized in that a wireless power transport device is provided on the power storage system and the cartridge side of the connection portion between the power storage system and the cartridge, and power can be exchanged without being physically connected. .

In addition, the present invention can be used for general houses, stores, buildings, factories, backup power supplies, mega solar power storage, wind power storage, geothermal power generation storage, electric vehicles, plug-in hybrid vehicles, and power storage systems that can be diverted to hybrid vehicles. It is.
As a result, the cartridge can be used not only for stationary use but also shared with other devices, so that it is possible to supply the power charged in the power storage system to other systems, and the cartridge can be generated by natural energy. It is possible to effectively use the power charged in the battery.

In the present invention, the power storage system is connected to the LAN, and the power generation amount of the future solar cell is calculated based on the weather forecast. As a result, the power generation amount of the solar cell is more than half of the rated output. If a certain period is less than a predetermined time, the output amount of the solar cell is predicted from the weather forecast, and the future solar cell power generation amount is calculated based on the weather forecast. However, if the period that is half or more of the rated output is equal to or longer than a predetermined time, power is not stored from the system.
According to this configuration, in order to promote effective utilization of electric power from solar cells and grids, it is possible to connect a power storage system to a LAN, obtain a weather forecast, and build an energy total management system that takes into account life patterns it can.

  Further, the cartridge of the present invention is characterized in that it can output a DC voltage and an AC voltage independently even when it is removed from the above-described power storage system.

  According to the present invention, a plurality of cartridges can be discharged or charged simultaneously and efficiently. In addition, according to the present invention, since the cross current prevention circuit that restricts the current for each of the cartridges to one direction of the discharge direction or the charge direction is provided, the terminals of the cartridges are discharged when a plurality of cartridges are discharged or charged simultaneously. It is possible to prevent the occurrence of cross current caused by the difference between the voltages.

It is a block diagram which shows the electric power grid | system of the electric power control system provided with the electrical storage system 6 which is one Embodiment of this invention. 2 is a diagram illustrating an external appearance example of a cell 101 and a cartridge 100. FIG. 3 is a diagram illustrating an example of specifications of a cell 101 and a cartridge 100. FIG. 4 is a diagram illustrating an appearance example of a power storage device 60. FIG. It is a figure explaining the connection of cartridge 100_1-100_4 in the electrical storage system 6. FIG. It is a figure explaining the connection of the backflow prevention circuit 65_i in the electrical storage system 6. FIG. 5 is a flowchart for explaining a process of discharging from the power storage system 6; 4 is a flowchart for explaining a process of charging the power storage system 6; 4 is a flowchart for explaining processing when a cartridge is extracted during discharge of the power storage system 6; 5 is a flowchart for explaining processing when a cartridge is extracted while the power storage system 6 is being charged. It is a figure which shows the result of the 1st cycle test of the electrical storage system. It is a figure which shows the result of the 2nd cycle test of the electrical storage system.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.
FIG. 1 is a block diagram illustrating a power system of a power control system including a power storage system according to an embodiment of the present invention. With reference to FIG. 1, an example of a partitioned area, for example, a power control system for a house, will be described. FIG. 1 shows a power supply path in a house, and direct current (DC) and alternating current (AC) are shown as types of power. For example, AC power of 220 V (60 Hz) flows through a home power network. The present invention is not limited to this, and can be used for automobiles and the like.

  The power generated by the power plant through the power supply network 1 is drawn into the home via the power meter 2 in the house. The power plant is a thermal power plant, a nuclear power plant, natural energy such as solar power or wind power. Note that the fee for the owner of the house to purchase the power supplied by the power supply company varies depending on the time of day. For example, a nighttime power charge with low power demand is displayed as a daytime charge and set at a low price.

  The power meter 2 is connected to a power management apparatus 4 that also serves as a gateway for a home power network, for example, via a wireless LAN (Local Area Network). The power meter 2 performs accurate measurement of the power supplied from the power supply network 1 to the home at a predetermined cycle, and transmits the measured value to the power management apparatus 4 through the wireless LAN by the communication unit. In this case, the measurement time is transmitted along with the measurement value. The time is time information common to the power network. For example, the reference time generation source is provided in any place on the power network, for example, in the power management apparatus 4.

  Commercial power that enters the home from the power meter 2 is supplied to the power distribution device 3 (plug strip). The power distribution device 3 is an instrument having a plurality of power plugs for supplying AC power. AC power is supplied to the power management device 4, the energization monitor 5, and the power storage system 6 of the present invention via the power distribution device 3. The power distribution device 3 supplies AC power to an electric appliance 51 in the home, for example, a television device and lighting, through the energization monitor 5. In addition, these electric appliances are examples, and actually more types of electric appliances are used in the home.

  The energization monitor 5 measures the power consumption of each of the electric appliances 51 connected to itself at a predetermined cycle, for example, a 1 second cycle. The energization monitor 5 transmits the measured power consumption information of each electric appliance and time information indicating the measurement time to the power management apparatus 4 by wireless communication.

  The solar panel 9 is constituted by a solar battery, generates DC power, and supplies the generated DC power to the solar module 10. The solar module 10 is configured by, for example, a DC-AC inverter, generates AC power synchronized with AC power in the home, and supplies the generated AC power to the power distribution device 3. In the power distribution device 3, the AC power from the power meter 2, the AC power from the solar module 10, and the AC power from the power storage system 6 are added and used as power in the house. Not only the solar panel 9 but also a wind power generator or the like that generates power with renewable energy may be used as the power generation device.

  The solar module 10 is connected to the power management apparatus 4 via a wireless LAN. The solar module 10 measures the direct-current power generated by the solar panel 9 and the alternating-current power supplied to the power network after the direct-current power is converted. The solar module 10 transmits the measured value of the AC power amount and time information indicating the measurement time to the power management apparatus 4 by wireless communication.

  The power storage system 6 includes a power storage device 60 in which, for example, four cartridges 100_1 to 100_4 are stored, a PCS (power conditioner), and a control circuit 62 as power storage devices in the home. The control circuit 62 controls operations such as charging and discharging of the cartridges 100_1 to 100_4 by the PCS according to an instruction signal transmitted from the power management apparatus 4 (details will be described later). The PCS converts the DC power stored in the power storage system 6 into AC power, and outputs the converted AC power to the power distribution device 3. The PCS converts AC power from the power distribution device 3 into DC power and charges the cartridges 100_1 to 100_4. The cartridges 100_1 to 100_4 and the PCS are connected by a wired interface such as SPI (Serial Peripheral Interface).

The power storage device 60 includes a plurality of electrical connection portions as connection portions into which the cartridges 100_1 to 100_4 are inserted and removed, respectively. This will be described later.
The control circuit 62 manages the state of the cartridges 100_1 to 100_4 and monitors safety and reliability. The control circuit 62 is connected to the power management apparatus 4 via a wireless LAN. The power management device 4 constantly receives information (storage capacity information) on the cartridges 100_1 to 100_4 from the control circuit 62, and transmits a control signal related to the cartridges 100_1 to 100_4 to the control circuit 62. Although details will be described later, each cartridge is configured to be removable from the power storage system 6 and is removed for use in other applications. That is, it is used as a power source for an electric device, for example, the electric vehicle 18.

The power management device 4 includes at least a control device 4a and an operation panel 4b.
The power management apparatus 4 is connected to an external server 17 on the Internet 16 via, for example, ADSL (Asymmetric Digital Subscriber Line).
The control device 4a receives various communication signals from various switches on the operation panel 4b, which is a driving operation unit that allows a user (resident) to set a driving operation, an external server 17 on the Internet 16, and a power storage system. Input circuit (not shown in FIG. 1). In addition, the control device 4a wirelessly outputs a signal for controlling the power meter 2 and the power storage system 6 on the basis of the microcomputer that executes various calculations using signals from the input circuit. Circuit. This microcomputer incorporates a RAM for storing calculation results and the like, and a ROM for storing preset control programs and updatable control programs, and controls the operation of a power storage system 6 and the like which will be described later.

  For example, the control device 4 a calculates the AC power that can be supplied by the solar module 10 based on the radio signal from the solar module 10 based on the DC voltage input from the solar panel 9 to the solar module 10. Further, the control device 4a calculates the AC power that can be supplied by the power storage system 6 based on the charging capacity of each cartridge that is input by a wireless signal from the power storage system 6. Further, the control device 4a receives AC power required for the electric appliance 51 from the energization monitor 5 by a radio signal. The control device 4a controls the power meter 2 based on the AC power that these devices communicate with each other by radio signals, and controls, for example, limits the input of AC power from the power supply network 1 to the power distribution device 3. Alternatively, the control device 4 a controls the power distribution device 3 to supply AC power from the solar module 10 to the power storage system 6, supply AC power from the power meter 2 to the power storage system 6, the power storage system 6 or the solar module 10. To supply AC power to the electric appliance 51. The operation status of the power storage system 6 and the charge capacity of each cartridge are displayed on a display screen provided on the operation panel 4b by an output signal from the control device 4a.

Further, the control device 4a has a power generation amount prediction means for obtaining a predicted value of the power generation amount by the solar panel 9 based on the weather prediction result in the external server 17 on the Internet 16 and the past power generation amount results in the house. Yes. In addition, the control device 4a has a function as a storage amount calculation unit that calculates a storage amount stored in the storage system in accordance with a predicted value of the power generation amount.
For example, when the user inputs an instruction to shift the power storage system 6 to an operating state via a switch on the operation panel 4b, the control device 4a displays the weather prediction result and the amount of power stored in the power storage system 6. In consideration of this, the amount of power stored in the power storage system 6 in the late-night charge time zone is determined. This power storage amount is calculated, for example, by subtracting the power storage amount remaining in the power storage system 6 and the power generation amount of the next day (predicted value of power generation amount) from the learning value based on the past actual power consumption by the user. The Then, the control device 4a sends a communication signal to the power meter 2 so as to receive the AC power from the power supply network 1 during the midnight charge time period when the power is cheap, for the amount of power calculated as the power storage amount calculation means. Wireless communication. The power meter 2 supplies AC power to the power storage system 6 via the power distribution device 3. Control device 4a wirelessly communicates a communication signal (charging instruction signal) for instructing current conversion to control circuit 62 of power storage system 6. The power storage system 6 converts the AC power from the power distribution device 3 into DC power and charges the cartridges 100_1 to 100_4.

  In addition, when the user inputs an instruction to shift the power storage system 6 to an operating state via a switch on the operation panel 4b, the control device 4a is in a state in which power can be generated by the solar panel 9 during the sunshine hours. A communication signal for instructing power conversion to the solar module 10 is communicated wirelessly. In addition, the control device 4a wirelessly communicates a communication signal (charging instruction signal) that instructs current conversion to the control circuit 62 of the power storage system 6. The solar module 10 takes in DC power from the solar panel 9, converts the DC power into AC power, and supplies it to the power storage system 6 via the power distribution device 3. The PCS of the power storage system 6 converts the AC power from the power distribution device 3 into DC power, and charges the cartridges 100_1 to 100_4 of the power storage system 6.

  In addition, when the user inputs an instruction to shift the power storage system 6 to an operating state via a switch on the operation panel 4b, the control device 4a, for example, contract power amount (power amount from the power supply network 1) ) So that AC power from the power storage system 6 is used. Specifically, a radio signal (discharge instruction signal) instructing power discharge from the cartridges 100_1 to 100_4 is output to the control circuit 62 of the power storage system 6. The PCS of the power storage system 6 converts the DC power maintained by the cartridge into AC power and outputs it to the power distribution device 3. The power distribution device 3 supplies AC power to the electric appliance 51 via the energization monitor 5. For example, if the AC power amount from the solar module 10 and the AC power amount from the power storage system 6 are larger than the power consumption amount of the electric appliance 51 used by the user, it is not necessary to use AC power from the power supply network 1. Therefore, the power management apparatus 4 can reduce the payment amount of the electricity bill by controlling the power meter 2 so that the power meter 2 does not receive AC power from the power supply network 1. Of course, although not shown in FIG. 1, when the electric appliance 51 is not used, the AC power from the solar module 10, or the AC power from the solar module 10 and the AC power from the power storage system 6, It is good also as a structure which sells electric power to etc.

Control device 4a performs the following control when the user inputs an intention to remove any cartridge in power storage system 6 via a switch on operation panel 4b. That is, the control device 4a wirelessly sends a cartridge extraction signal and a signal indicating the identification number of the cartridge to the control circuit 62 of the power storage system 6 regardless of whether the power storage system 6 is being charged or discharged. connect. The control circuit 62 of the power storage system 6 is a switch circuit provided in the power storage system 6 depending on whether the power storage system 6 is being charged or discharged, and depending on the power storage state of the cartridge (discharged or charged). Conduction or non-conduction control (described later) is performed.
Details of the control (charging, discharging, cartridge removal) of the power storage system by the instruction signal from the power management device 4 will be described later, and the configuration of the power storage system 6 that is a characteristic part of the present application will be described in detail below.

FIG. 2 is a diagram illustrating an appearance example of the cell 101 and the cartridge 100. FIG. 3 is a diagram illustrating an example of specifications of the cell 101 and the cartridge 100.
As shown in FIG. 2A, the cell 101 has a substantially rectangular parallelepiped shape, and tabs (a positive electrode terminal and a negative electrode terminal) are provided on one surface. As shown in FIG. 3, for example, the size of the cell 101 is about 160 mm in horizontal width, about 3 mm in height (thickness), and about 80 mm in vertical width (depth). Note that the size of the cell is not limited to this, and can be freely designed according to each application. For example, in the case of residential use, the width is about 100 to 300 mm, the height (thickness) is about 1 to 10 mm, and the vertical width (depth) is about 50 to 200 mm from the viewpoint of replacement or use alone. More preferably, the lateral width is about 130 to 180 mm, the height (thickness) is about 2 to 5 mm, and the vertical width (depth) is about 60 to 100 mm. In the case of large-scale applications, from the viewpoint of replacement, it is preferable that the width is about 200 to 1000 mm, the height (thickness) is about 5 to 20 mm, the vertical width (depth) is about 200 to 1000 mm, and the width is 300 to 1000 mm. More preferably, it is about 700 mm, the height (thickness) is about 8 to 15 mm, and the vertical width (depth) is about 300 to 700 mm. The shape of the cell is not limited to that shown in FIG. 2, but is a combination of an ellipsoid, a cylinder, a cuboid, a cuboid, a rhombus, or a plurality of ellipsoids, a cylinder, a cuboid, a cuboid, and a rhombus. However, it may be a combination of different types of shapes. In view of productivity, it is preferably a rectangular parallelepiped, a rectangular parallelepiped, an ellipsoid, a cylindrical shape, or a combination thereof.
The cell 101 as a device for storing electricity includes a lithium ion secondary battery (hereinafter also referred to as LiB), a nickel metal hydride secondary battery, a lead storage battery, a nickel cadmium battery, a redox flow battery, a zinc chlorine battery, a zinc bromine battery, a lithium air battery, and aluminum. It is comprised from either an air battery, an air zinc battery, a sodium sulfur battery, a lithium iron sulfide battery, or an air magnesium battery.

The cartridge 100 is composed of a plurality of cells 101. In FIG. 2B, the case where the cartridge 100 is composed of 17 cells is illustrated. In the cartridge 100, 17 cells are stored side by side, and the tabs of the cells are electrically connected by welding, and are stored in the housing of the cartridge.
For example, as shown in FIG. 3, the cartridge has a width of about 200 mm, a height (thickness) of about 50 mm, and a vertical width (depth) of about 120 mm. The size of the cartridge is not limited to this, and can be freely designed according to each application. For example, in the case of home placement, the width is about 150 to 700 mm, the height (thickness) is about 10 to 150 mm, and the vertical width (depth) is about 75 to 500 mm from the viewpoint of replacement and use alone. More preferably, the lateral width is about 200 to 500 mm, the height (thickness) is about 30 to 120 mm, and the vertical width (depth) is about 100 to 300 mm. In the case of large-scale applications, from the viewpoint of installation and maintenance, the width is preferably about 300 to 2000 mm, the height (thickness) is about 40 to 300 mm, and the vertical width (depth) is preferably about 300 to 2000 mm. Is more preferably about 300 to 1500 mm, the height (thickness) is about 50 to 150 mm, and the vertical width (depth) is about 300 to 1500 mm.
When the cells are mounted on the cartridge 100, the cells are connected in series on the cartridge 100 side. In FIG. 2B and FIG. 3, the case where the cartridge has 17 cells has been described. However, the number of cells is not limited to this, and the number of cells is not limited to this. It can be designed freely according to the voltage and power amount. For example, in the case of residential use, the number is preferably about 10 to 150, more preferably about 15 to 120, from the viewpoint of system interconnection and use of the cartridge alone. In the case of large-scale applications, from the viewpoint of grid connection, about 80 to 300 are preferable, and 100 to 250 are more preferable. Further, when creating a thin cartridge, one, two, or four or more may be used.

A safety circuit 102 is provided in the cartridge 100. The safety circuit 102 controls charging / discharging of each cell so that overcharge and overdischarge do not occur. In order to control uniform charging to these cells 101, an active cell balance and a passive cell balance BMS (Battery Management System) may be installed in the cartridge. The BMS and the safety circuit are controlled by a control circuit 62 described later, but the description of the present application is omitted because it is not a characteristic part. On the other hand, the BMS may be installed not on the cartridge but on the power storage system side. In that case, it is necessary to incorporate a circuit so that the voltage of each cell in the cartridge can be detected from the BMS on the storage battery system side.
The handle 103 is provided outside the cartridge, and is used when the cartridge 100 is attached to, detached from, and transported from the power storage device 60. Further, the cartridge 100 is provided with a positive terminal 111 that is a positive terminal and a negative terminal 112 that is a negative terminal. From the + terminal 111 and the −terminal 112 of the cartridge 100, the DC voltage of the cells 101 connected in series can be taken out of the cartridge. Further, by applying a DC voltage between the terminals, it is possible to charge the cells connected in series.
If the cartridge 100, the cell 101, the safety circuit 102, the handle 103, the positive (+) terminal 111 as the positive terminal, and the negative (-) terminal 112 as the negative terminal can perform the above functions, FIG. 5 is not limited to FIG. 5 and can be freely designed according to each application.

  The cartridge 100 is a cartridge type pack in which a plurality of cells 101 are connected. The cartridge 100 is a component that can be detached from the power storage device 60 as described below. The weights and ratings of the cell 101 and the cartridge 100 are as shown in FIG. For example, the energy of the cell 101 is 11.1 Wh, but the energy is not limited to this, and it can be designed freely according to each application. For example, in the case of residential use, it is preferably about 5 to 500 Wh, more preferably about 10 to 300 Wh, from the viewpoint of using the cartridge alone. In the case of a large-scale application, it is preferably about 100 to 5000 Wh, more preferably about 500 to 3000 Wh from the viewpoint of maintenance.

FIG. 4 is a diagram illustrating an appearance example of the power storage device 60. In this figure, a cover 22 is provided on one side of the power storage device 60 so as to be openable and closable. This cover 22 opens in the lateral direction. Two terminals are provided in the cover 22 as electrical connection portions for inputting and outputting voltage (not shown in FIG. 4). When the cartridge 100 is fitted into the power storage device 60, the cover 22 is opened, and the electrical connection portion on the power storage device 60 side with the + terminal 111 and the − terminal 112 of the cartridge 100 is exposed. When the cartridge is fitted into the power storage device 60, an electrical connection between the power storage device 60 and the cartridge 100 is formed at the connection portion of the power storage device 60. In FIG. 4, three cartridges (cartridges 100_1, 100_2, and 100_3) are mounted on the power storage device 60.
In the present embodiment, the power storage device 60 can be connected to four cartridges having substantially the same shape at the maximum. Further, even if the shape of the receptacle on the power storage system side is changed, the cartridge can be used even if the shape and capacity of the cartridge are different. The size of the power storage device 60 can be freely changed depending on the application environment of the power storage system 6, and four or more cartridges can be connected.

  In addition, each cartridge can be easily attached / detached (inserted and removed) from the power storage device 60. In the power storage device 60, the cartridges are connected in parallel to a switch circuit described later via a PCS (not shown in FIG. 4). According to these inventions, not only can it be used as a power storage system for houses, buildings, factories, etc., but also a cartridge and PCS, or a single cartridge can be diverted to an electric vehicle 18 (see FIG. 1), Further, maintenance is facilitated by the control of the control circuit 62 as will be described later.

FIG. 5 is a diagram illustrating the connection of the cartridges 100_1 to 100_4 in the power storage system 6. FIG. 6 is a diagram for explaining the connection of the backflow prevention circuit 65 — i in the power storage system 6.
The power storage system 6 includes a power storage device 60, a PCS (power conditioner), a control circuit 62, and a cross current prevention circuit (CCP) 65_1 to 65_4. The PCS includes a bidirectional DC-DC converter 61a and a bidirectional DC-AC inverter 61b.

  The cross current prevention circuit 65_i (the symbol i is any one of 1 to 4, and the symbol i is used as a symbol corresponding to the configuration (circuit and control signal) to be controlled) is as shown in FIG. In addition, a diode 66_i (second diode), a switch circuit 67_i (second switch circuit), a switch circuit 68_i (first switch circuit), and a diode 69_i (first diode) are included. The cross current prevention circuit 65_i limits the current to each of the cartridges 100_1 to 100_4 in one direction, thereby preventing the occurrence of cross current.

The diode 66_i and the switch circuit 67_i are connected in series. The diode 66_i and the switch circuit 67_i form a current path that allows the current Ia to flow only in one direction of charging with respect to the cartridge 100_i.
That is, in the diode 66_i, the anode terminal is connected to one end of the switch circuit 67_i, and the cathode terminal is connected to the + terminal 111_i of the cartridge 100_i. In the switch circuit 67_i, one end is connected to the anode terminal of the diode 66_i, and the other end is connected to the input / output terminal (positive terminal) of the bidirectional DC-DC converter 61a.

The diode 69_i and the switch circuit 68_i are connected in series. The diode 69_i and the switch circuit 68_i form a current path through which the current Ib flows only in one direction of the discharge direction.
That is, one end of the switch circuit 68_i is connected to the + terminal 111_i of the cartridge 100_i, and the other end is connected to the anode terminal of the diode 69_i. In the diode 69_i, the anode terminal is connected to the other end of the switch circuit 68_i, and the cathode terminal is connected to the input / output terminal (positive terminal) of the bidirectional DC-DC converter 61a.

  The switch circuit 67_i is controlled by a PCS control signal PCSC_i from the control circuit 62. That is, the switch circuit 67_i is turned off when the PCS control signal PCSC_i is at the L level, and turned on when the PCS control signal PCSC_i is at the H level. The switch circuit 68_i is controlled by a PCS control signal PCSD_i from the control circuit 62. That is, the switch circuit 68_i is turned off when the PCS control signal PCSD_i is at the L level, and turned on when the PCS control signal PCSD_i is at the H level.

  When the switch circuit 68_i is off and the switch circuit 67_i is on, the current Ia can be limited to flow only in the charging direction of the cartridge 100_i. When the switch circuit 67_i is off and the switch circuit 68_i is on, the current Ib can be limited to flow only in the discharge direction of the cartridge 100_i.

  The diode 66_i and the switch circuit 67_i in the cross current prevention circuit 65_i may be connected in series. The switch circuit 67_i is disposed on the + terminal 111_i side, and the diode 66_i is disposed on the bidirectional DC-DC converter 61a side. These may be connected in series. The diode 69_i and the switch circuit 68_i in the cross current prevention circuit 65_i only need to be connected in series. The diode 69_i is disposed on the + terminal 111_i side, and the switch circuit 68_i is disposed on the bidirectional DC-DC converter 61a side. These may be connected in series.

  Returning to FIG. 5, the + terminals 111_1 to 111_4 of the cartridges 100_1 to 100_4 are connected to the input / output terminals (positive terminal) on the power storage device 60 side of the bidirectional DC-DC converter 61a via the cross current prevention circuits 65_1 to 65_4. Connected. The negative terminals 112_1 to 112_4 of the cartridges 100_1 to 100_4 are connected to the input / output terminals (negative terminal) on the power storage device 60 side of the bidirectional DC-DC converter 61a.

In the bidirectional DC-DC converter 61a constituting the PCS, the input / output terminal (positive terminal) on the power storage device 60 side is connected to the + terminals 111_1 of the cartridges 100_1 to 100_4 via the cross current prevention circuits 65_1 to 65_4 as described above. To 111_4, respectively. In the bidirectional DC-DC converter 61a constituting the PCS, the input / output terminals (negative terminal) on the power storage device 60 side are connected to the negative terminals 112_1 to 112_4 of the cartridges 100_1 to 100_4.
In the bidirectional DC-AC inverter 61b constituting the PCS, the input / output terminal on the power storage device 60 side is connected to the input / output terminal on the power distribution device 3 side of the bidirectional DC-DC converter 61a. Input / output terminals (nodes that output a commercial voltage) are connected to the power distribution device 3.

  In the present embodiment, the configuration of the PCS (power conditioner) includes a bidirectional DC-DC converter and a bidirectional DC-AC inverter. However, this is only an example, and the configuration of the PCS is provided with two sets of unidirectional DC-DC converters and unidirectional DC-AC inverters (respectively PCS1 and PCS2), each set in the opposite direction. It is good also as a structure which supplies a voltage to. In the case of adopting this configuration, the connection between each of the PCS1 and PCS2, the cartridges 100_1 to 100_4, and the power distribution device 3 is as follows.

That is, in PCS1, the input terminal (positive electrode side terminal) on the power storage device 60 side is connected to the + terminals 111_1 to 111_4 of the cartridges 100_1 to 100_4 via the cross current prevention circuits 65_1 to 65_4, respectively. In PCS1, the input terminal (negative terminal) on the power storage device 60 side is connected to the negative terminals 112_1 to 112_4 of the cartridges 100_1 to 100_4. In PCS 1, the output terminal on the power storage device 60 side is connected to the power distribution device 3.
On the other hand, in PCS2, the output terminal (positive terminal) on the power storage device 60 side is connected to the + terminals 111_1 to 111_4 of the cartridges 100_1 to 100_4 through the cross current prevention circuits 65_1 to 65_4, respectively. In PCS2, the output terminal (negative electrode side terminal) on the power storage device 60 side is connected to the negative terminals 112_1 to 112_4 of the cartridges 100_1 to 100_4. In the PCS 2, the input terminal on the power storage device 60 side is connected to the power distribution device 3.
As described above, the PCS (power conditioner) converts the commercial voltage into a DC voltage by simultaneously charging a plurality of cartridges 100_1 to 100_4 connected in parallel, or simultaneously charges a plurality of cartridges 100_1 to 100_4 connected in parallel. What is necessary is just to discharge and output a commercial voltage, and any of a bidirectional | two-way, one-way DC-DC converter, and a DC-AC inverter may be used.

The control circuit 62 is a control signal (discharge instruction signal, charge instruction signal) transmitted by the power management device 4 for the step-up / step-down operation by the bidirectional DC-DC converter 61a and the power conversion operation by the bidirectional DC-AC inverter 61b. Depending on
Specifically, when a discharge instruction signal is input, the control circuit 62 controls the bidirectional DC-DC converter 61a so as to input a DC voltage (cartridge sustain voltage) input to the input / output terminal on the power storage device 60 side. ) And the boosted DC voltage (for example, a DC voltage of 300 V) is output to the input / output terminal on the power distribution apparatus 3 side. In addition, the control circuit 62 controls the bidirectional DC-AC inverter 61b to convert the DC voltage input to the input / output terminal on the power storage device 60 side into an AC voltage (for example, an AC voltage of 100V or 200V), Output to the input / output terminal on the power distribution device 3 side. The power distribution device 3 receives this AC voltage and supplies an operating voltage to the electric appliance 51 via the energization monitor 5, for example. Note that control of the PCS by the control circuit 62 is performed throughout a period in which the discharge instruction signal is input.

  In addition, when a charging instruction signal is input, the control circuit 62 controls the bidirectional DC-AC inverter 61b to convert the AC voltage input to the input / output terminal on the power distribution device 3 side into a DC voltage, Output to the input / output terminal on the device 60 side. In addition, the control circuit 62 controls the bidirectional DC-DC converter 61a to step down the direct current voltage input to the input / output terminal on the power distribution device 3 side, and the reduced direct current voltage is input / output on the power storage device 60 side. Output to the terminal. The cartridges 100 </ b> _ <b> 1 to 100_ <b> 4 in the power storage device 60 are transferred to a state where they are supplied with this DC voltage. Note that control of the PCS by the control circuit 62 is performed throughout a period in which the charge instruction signal is input.

  Further, the control circuit 62 opens and closes (non-conducting and conducting) the switch circuits 67_1 to 67_4 and the switch circuits 68_1 to 68_4 constituting the cross current prevention circuits 65_1 to 65_4 according to a control signal transmitted from the power management device 4. Control.

  Specifically, when neither the discharge instruction signal nor the charge instruction signal is input (in the default state), the control circuit 62 includes the switch circuits 67_1 to 67_4 and the switch circuits 68_1 to 68_4 in the cross current prevention circuits 65_1 to 65_4. Are all open (non-conducting, off-state).

  When the control signal is a discharge instruction signal (a signal indicating a discharge instruction from power storage device 60), control circuit 62 sets PCS control signals PCSD_1 to PCSD_4 to H level and sets PCS control signals PCSC_1 to PCSC_4 to L level. In the cross current prevention circuits 65_1 to 65_4, the control circuit 62 performs control so that the switch circuits 68_1 to 68_4 are turned on and the switch circuits 67_1 to 67_4 are turned off. In this case, in each cross current prevention circuit 65_i, the switch circuit 68_i and the diode 69_i form a current path through which the current Ib flows only in one direction of the discharge direction.

  When the control signal is a charging instruction signal (a signal indicating a charging instruction to power storage device 60), control circuit 62 sets PCS control signals PCSC_1 to PCSC_4 to H level and sets PCS control signals PCSD_1 to PCSD_4 to L level. The control circuit 62 performs control so that the switch circuits 67_1 to 67_4 in the cross current prevention circuits 65_1 to 65_4 are turned on and the switch circuits 68_1 to 68_4 are turned off. In this case, in each cross current prevention circuit 65_i, the switch circuit 67_i and the diode 66_i form a current path through which the current Ia flows only in one direction of the charging direction.

  Further, it is assumed that the control signal input from the power management apparatus 4 during discharging is a cartridge extraction signal and a signal indicating the identification number of the cartridge. As described above, during discharge, in the cross current prevention circuits 65_1 to 65_4, the switch circuits 68_1 to 68_4 are turned on and the switch circuits 67_1 to 67_4 are turned off. When the control circuit 62 receives the cartridge extraction signal and the signal indicating the identification number of the cartridge, the control circuit 62 sets the PCS control signal PCSD_j (j indicates the cartridge to be extracted) to the L level, and the user extracts it. The switch circuit 68_j corresponding to the cartridge intended for is turned off. Then, the control circuit 62 outputs to the power management apparatus 4 a signal for instructing that the user may remove the cartridge that the user intends to remove. The power management device 4 displays on the display unit of the operation panel 4b that the cartridge may be removed, and the user can safely remove the cartridge from the power storage device 60.

  Further, it is assumed that the control signal input from the power management device 4 during charging is a cartridge extraction signal and a signal indicating the identification number of the cartridge. As described above, during charging, in the cross current prevention circuits 65_1 to 65_4, the switch circuits 67_1 to 67_4 are turned on and the switch circuits 68_1 to 68_4 are turned off. When the control circuit 62 receives the cartridge extraction signal and the signal indicating the identification number of the cartridge, the control circuit 62 sets the PCS control signal PCSC_j (j indicates the cartridge to be extracted) to the L level, and the user extracts it. The switch circuit 67_j corresponding to the cartridge intended for is turned off. Then, the control circuit 62 outputs to the power management apparatus 4 a signal for instructing that the user may remove the cartridge that the user intends to remove. The power management device 4 displays on the display unit of the operation panel 4b that the cartridge may be removed, and the user can safely remove the cartridge from the power storage device 60.

FIG. 7 is a flowchart for explaining a process of discharging from the power storage system 6.
The control circuit 62 turns off the switch circuits 67_1 to 67_4 and the switch circuits 68_1 to 68_4 in the cross current prevention circuits 65_1 to 65_4 in a state where neither the discharge instruction signal nor the charge instruction signal is input from the power management device 4. (Step S1). Specifically, the control circuit 62 maintains all the PCS control signals PCSC_1 to PCSC_4 and the PCS control signals PCSD1 to PCSD4 at the L level.

  When the discharge instruction signal is input from the power management device 4 (step S2), the control circuit 62 shifts to an AC voltage supply operation from the cartridge to the power distribution device 3. The control circuit 62 changes the PCS control signals PCSD_1 to PCSD_4 from the L level to the H level. As a result, in the cross current prevention circuits 65_1 to 65_4, the switch circuits 68_1 to 68_4 are turned on (step S3). For this reason, in each cross current prevention circuit 65_i, the switch circuit 68_i and the diode 69_i form a current path through which the current Ib flows only in the discharge direction of the cartridge 100_i.

  Further, the control circuit 62 controls the bidirectional DC-DC 61a to boost the DC voltage input from each cartridge 100_1 to 100_4 to, for example, a DC voltage of 300V. In addition, the control circuit 62 controls the bidirectional DC-AC inverter 61b to convert the DC voltage input from the bidirectional DC-DC converter 61a into, for example, an AC voltage of 100V or 200V. The power distribution device 3 is supplied with an AC voltage converted from each DC voltage of each of the cartridges 100_1 to 100_4, and supplies an operating voltage to the electric appliance 51 through the energization monitor 5, for example. Accordingly, the plurality of cartridges 100_1 to 100_4 are simultaneously discharged (step S4).

  The control circuit 62 monitors the cartridge voltage, and when the cartridge voltages of all the cartridges 100_1 to 100_4 become 46.8V (first voltage) or less (step S5), the PCS control signals PCSD_1 to PCSD_4 are changed from the H level. Change to L level. Thereby, the switch circuits 68_1 to 68_4 in the cross current prevention circuits 65_1 to 65_4 are turned off (step S6), and the current paths of both the discharge current Ib and the charge current Ia are blocked in each of the cross current prevention circuits 65_i.

  For example, the control circuit 62 outputs a signal indicating the end of discharge to the power management apparatus 4 (step S7). The power management apparatus 4 displays on the display device provided on the operation panel 4b that the discharge operation from the power storage system 6 has been completed. Note that the power management device 4 may be configured to display that the power storage system 6 is discharging from when the power management device 4 outputs a discharge instruction signal to the power storage system 6 until the end of the discharge.

Next, a process for charging the power storage system 6 will be described. FIG. 8 is a flowchart for explaining a process of charging the power storage system 6.
The control circuit 62 turns off the switch circuits 67_1 to 67_4 and the switch circuits 68_1 to 68_4 in the cross current prevention circuits 65_1 to 65_4 in a state where neither the discharge instruction signal nor the charge instruction signal is input from the power management device 4. (Step S11). Specifically, the PCS control signals PCSC_1 to PCSC_4 and the PCS control signals PCSD_1 to PCSD_4 are maintained at the L level.

  When the charge instruction signal is input from the power management device 4 (step S12), the control circuit 62 shifts to a DC voltage supply operation to the cartridge. The control circuit 62 changes the PCS control signals PCSC_1 to PCSC_4 from the L level to the H level. As a result, in the cross current prevention circuits 65_1 to 65_4, the switch circuits 67_1 to 67_4 are turned on (step S13). For this reason, in each cross current prevention circuit 65_i, the switch circuit 67_i and the diode 66_i form a current path through which the current Ia flows only in the charging direction of the cartridge 100_i.

  In addition, the control circuit 62 controls the bidirectional DC-AC inverter 61b to convert the AC voltage input from the power distribution device 3 into a DC voltage. The control circuit 62 controls the bidirectional DC-DC converter 61a to step down the direct current voltage input from the bidirectional DC-AC converter 61a to the direct current voltage. Thereby, the plurality of cartridges 100_1 to 100_4 are simultaneously charged. (Step S14)

  The control circuit 62 monitors the cartridge voltage, and when the cartridge voltages of all the cartridges 100_1 to 100_4 become 68 V (second voltage) or more (step S15), the PCS control signals PCSC_1 to PCSC_4 are changed from the H level to the L level. To change. Thereby, in the cross current prevention circuits 65_1 to 65_4, the switch circuits 67_1 to 67_4 are turned off (step S16), and the current paths of both the discharge current Ib and the charge current Ia are blocked in each of the cross current prevention circuits 65_i. However, when the number of cells in the cartridge changes, the second voltage changes. For example, when the end voltage of the cell is 4.15V, the second voltage is 415V for 100 cartridges connected in series.

  For example, the control circuit 62 outputs a signal indicating the end of charging to the power management apparatus 4 (step S17). The power management apparatus 4 displays on the display device provided on the operation panel 4b that the charging operation from the power storage system 6 has been completed. Note that the power management device 4 may be configured to display that the power storage system 6 is being charged from when the power management device 4 outputs a charging instruction signal to the power storage system 6 until the end of charging.

Next, processing when the cartridge is extracted during discharge to the power storage system 6 will be described. FIG. 9 is a flowchart for explaining processing when the cartridge is removed during discharging of the power storage system 6.
FIG. 9 shows processing when the cartridge extraction signal and the signal indicating the identification number of the cartridge 100 — j are input to the control circuit 62 while the cartridge is discharged. Note that the cartridge 100_j indicates a cartridge to be extracted from the cartridges 100_1 to 100_4.

  The control circuit 62 turns off the switch circuits 67_1 to 67_4 and the switch circuits 68_1 to 68_4 in the cross current prevention circuits 65_1 to 65_4 in a state where neither the discharge instruction signal nor the charge instruction signal is input from the power management device 4. It is in a state (step S21). Specifically, the control circuit 62 maintains the PCS control signals PCSC_1 to PCSC_4 and the PCS control signals PCSD_1 to PCSD_4 at the L level.

  When the discharge instruction signal is input from the power management device 4 (step S22), the control circuit 62 shifts to an AC voltage supply operation from the cartridges 100_1 to 100_4 to the power distribution device 3. The control circuit 62 changes the PCS control signals PCSD_1 to PCSD_4 from the L level to the H level. As a result, in the cross current prevention circuits 65_1 to 65_4, the switch circuits 68_1 to 68_4 are turned on (step S23). Therefore, in each cross current prevention circuit 65_i, a current path through which the current Ib flows only in the discharge direction to the cartridge 100_i is formed by the switch circuit 68_i and the diode 69_i. Further, the control circuit 62 controls the bidirectional DC-DC converter 61a to boost the DC voltage input from the cartridges 100_1 to 100_4 to, for example, a DC voltage of 300V. In addition, the control circuit 62 controls the bidirectional DC-AC inverter 61b to convert the DC voltage input from the bidirectional DC-DC converter 61a into, for example, an AC voltage of 100V or 200V. The power distribution device 3 receives an AC voltage converted from the DC voltage of the cartridges 100_1 to 100_4, and supplies an operating voltage to the electric appliance 51 through, for example, the energization monitor 5 (step S24).

  When the user inputs an instruction to remove the cartridge 100_j from the operation panel 4b of the power management apparatus 4 until the cartridge voltage of all the cartridges 100_1 to 100_4 reaches 46.8V (first voltage). The control circuit 62 receives a cartridge extraction signal and a signal indicating the identification number of the cartridge 100_j (step S25). However, the first voltage changes as the number of cells in the cartridge changes. For example, when the end voltage of the cell is 2.7V, the second voltage is 270V for 100 cartridges connected in series.

  The control circuit 62 turns off the switch circuit 68_j in the cross current prevention circuit 65_j corresponding to the cartridge 100_j (step S26). Specifically, the control circuit 62 changes the PCS control signal PCSD_j from the H level to the L level. Accordingly, the switch circuit 68_j of the cross current prevention circuit 65_j corresponding to the cartridge 100_j is turned off.

  Next, since the cartridge 100_j is no longer in the discharged state, the control circuit 62 outputs a signal instructing to display that the cartridge 100_j may be removed to the power management apparatus 4. The power management apparatus 4 displays on the display device provided on the operation panel 4b that the cartridge 100_j may be removed from the power storage system 6 (step S27). Since the cartridge 100_j is excluded from the discharge target, the user can safely remove the cartridge 100_j (step S28).

Next, processing when the cartridge is removed during charging from the power storage system 6 will be described. FIG. 10 is a flowchart for explaining processing when the cartridge is removed while the power storage system 6 is being charged.
FIG. 10 shows processing when the cartridge extraction signal and the signal indicating the identification number of the cartridge 100_j are input to the control circuit 62 while the cartridge is being charged. Note that the cartridge 100_j indicates a cartridge to be extracted from the cartridges 100_1 to 100_4.

  The control circuit 62 turns off the switch circuits 67_1 to 67_4 and the switch circuits 68_1 to 68_4 in the cross current prevention circuits 65_1 to 65_4 in a state where neither the discharge instruction signal nor the charge instruction signal is input from the power management device 4. The state is set (step S31). Specifically, the control circuit 62 maintains the PCS control signals PCSC_1 to PCSC_4 and the PCS control signals PCSD_1 to PCSD_4 at the L level.

  When the charging instruction signal is input from the power management device 4, the control circuit 62 shifts to a DC voltage supply operation to the cartridges 100_1 to 100_4 (step S32). The control circuit 62 changes the PCS control signals PCSC_1 to PCSC_4 from the L level to the H level. Thereby, in the cross current prevention circuits 65_1 to 65_4, the switch circuits 67_1 to 67_4 are turned on (step S33). For this reason, in each cross current prevention circuit 65_i, the switch circuit 67_i and the diode 66_i form a current path through which the current Ia flows only in the charging direction of the cartridge 100_i. In addition, the control circuit 62 controls the bidirectional DC-AC inverter 61b to convert the AC voltage input from the power distribution device 3 into a DC voltage. Further, the control circuit 62 controls the bidirectional DC-DC converter 61a to step down the DC voltage input from the bidirectional AC-DC converter 61b (step S34).

  When the user inputs an instruction to remove the cartridge 100_j from the operation panel 4b of the power management apparatus 4 until the cartridge voltage of all the cartridges 100_1 to 100_4 reaches 68V (second voltage), the control is performed. The circuit 62 receives a cartridge extraction signal and a signal indicating the identification number of the cartridge 100_j (step S35).

  The control circuit 62 turns off the switch circuit 67_j in the cross current prevention circuit 65_j corresponding to the cartridge 100_j (step S36). Specifically, the control circuit 62 changes the PCS control signal PCSC_j of the cross current prevention circuit 65_j corresponding to the cartridge 100_j from the H level to the L level. Accordingly, the switch circuit 67_j of the cross current prevention circuit 65_j corresponding to the cartridge 100_j is turned off.

  Next, since the cartridge 100_j is no longer in the charged state, the control circuit 62 outputs a signal instructing to display that the cartridge 100_j may be removed to the power management apparatus 4. The power management apparatus 4 displays on the display device provided on the operation panel 4b that the cartridge 100_j may be removed from the power storage system 6 (step S37). Since the cartridge 100_j is excluded from the charging target, the user can safely remove the cartridge 100_j (step S38).

Next, the results of a cycle test when a plurality of cartridges are charged and discharged simultaneously using this embodiment will be described. FIG. 11 is a diagram illustrating a result of the first cycle test of the power storage system 6. FIG. 12 is a diagram illustrating a result of the second cycle test of the power storage system 6.
In the first test, as shown in FIG. 11A, discharge and charging are repeated using a cartridge having the same capacity (2900 Wh) under the conditions shown in FIG. 11A. FIG. 11B shows the discharge result, and FIG. 11C shows the charge result. In this cycle test, when charging and discharging were not performed, no current value was observed, and it was confirmed that there was no cross current. This is due to the action of the cross current prevention circuit including a diode and a switch circuit. Note that the reason why the charge and discharge capacities do not reach the theoretical values is considered to be the occurrence of heat loss due to the diode.

  In the second test, as shown in FIG. 12A, discharging and charging are repeated under the conditions shown in FIG. 12A using cartridges having different capacities (2900 Wh, 2900 Wh, 2400 Wh). is there. FIG. 12B shows the discharge result, and FIG. 12C shows the charge result. Even in this cycle test, when charging and discharging were not performed, no current value was observed, and it was confirmed that there was no cross current. This is due to the action of the cross current prevention circuit including a diode and a switch circuit. Note that the reason why the charge and discharge capacities do not reach the theoretical values is considered to be the occurrence of heat loss due to the diode.

  As described above, the power storage system 6 according to the present invention connects a plurality of cartridges 100_1 to 100_4 including a plurality of connected cells in parallel, and supplies current to each of the cartridges 100_1 to 100_4 in one direction of discharging or charging. Cross current prevention circuits 65_1 to 65_4 for limiting are provided, and a plurality of cartridges 100_1 to 100_4 connected in parallel are converted into a DC voltage and charged simultaneously, or a plurality of cartridges 100_1 to 100_4 connected in parallel are connected. Are discharged simultaneously to output the commercial voltage.

  The power storage system 6 is provided between a bidirectional DC-DC converter 61a provided in common to the cartridges 100_1 to 100_4 connected in parallel, and a bidirectional DC-DC converter 61a and a node that outputs a commercial voltage. Cross current including bi-directional DC-AC inverter 61b, diodes 66_1-66_4, 69_1-69_4 and switch circuits 67_1-67_4, 68_1-68_4 for limiting the current to each of the cartridges 100_1 to 100_4 in one direction of discharging or charging. And a control circuit 62 that controls conduction or non-conduction of the switch circuits 67_1 to 67_4 and 68_1 to 68_4 constituting the plurality of cross current prevention circuits 65_1 to 65_4.

  According to the electricity storage system 6 of the present invention, since a plurality of cartridges are discharged or charged simultaneously, discharging or charging can be performed efficiently. In addition, according to the power storage system 6 of the present invention, the cross current prevention circuits 65_1 to 65_4 for limiting the current in one direction are provided, so that even if a plurality of cartridges are discharged or charged simultaneously, the occurrence of the cross current is prevented. it can.

In addition, a program for realizing the function of the power storage system 6 in FIG. 1 is recorded on a computer-readable recording medium, and the program recorded on the recording medium is read into the computer system and executed, thereby executing charge / discharge management. May be performed. Here, the “computer system” includes an OS and hardware such as peripheral devices.
Further, the “computer system” includes a homepage providing environment (or display environment) if a WWW system is used.
The “computer-readable recording medium” refers to a storage device such as a flexible medium, a magneto-optical disk, a portable medium such as a ROM and a CD-ROM, and a hard disk incorporated in a computer system. Further, the “computer-readable recording medium” refers to a volatile memory (RAM) in a computer system that becomes a server or a client when a program is transmitted via a network such as the Internet or a communication line such as a telephone line. In addition, those holding programs for a certain period of time are also included. The program may be a program for realizing a part of the functions described above, and may be a program capable of realizing the functions described above in combination with a program already recorded in a computer system.

  The embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to this embodiment, and includes modifications and the like without departing from the gist of the present invention.

  For example, in the above embodiment, a power storage system that can be diverted to a general house has been described. The power storage system of the present invention may be diverted to stores, buildings, factories, backup power supplies, mega solar power storage, wind power storage, geothermal power generation power storage, electric vehicles, plug-in hybrid vehicles, and hybrid vehicles.

  In the above-described embodiment, an example in which the cartridge and the power storage system are physically connected has been described. With respect to the connection portion between the power storage system and the cartridge, a wireless power transfer device may be provided on the power storage system and cartridge side, and power may be exchanged without being physically connected. When removing the cartridge, for safety reasons, it is desirable not to expose the connection portion such as the electrode tab from the viewpoint of avoiding contact failure. Therefore, an electrical component (such as a spiral wire) may be provided on the power transfer side and the power supply side so that wireless charging can be performed.

  Moreover, in the said embodiment, it was set as the structure which the electric power management apparatus 4 controls the charge to the electrical storage system 6 or the discharge from the electrical storage system 6 based on an electrical forecast. In order to further promote effective utilization of electric power from the solar cell and the system, the following configuration may be adopted. In other words, the future solar cell power generation amount is calculated based on the weather forecast, and if the calculated power generation amount of the solar cell is more than half of the rated output is less than the predetermined time, the weather forecast The output amount of the solar cell is predicted from the weather forecast, and the future solar cell power generation amount is calculated based on the weather forecast. As a result of the calculation, the period during which the solar cell power generation amount is more than half of the rated output is determined in advance. If it is longer than the predetermined time, the power may not be stored from the grid.

  Further, the size and characteristics of the cartridge 100 and the cell 101 shown in FIG. 3 are examples, and are not limited to the dimensions shown in the drawing. Further, the voltage values of the determination voltages (first voltage and second voltage) when the control circuit 62 turns on or off the switch circuits 67_1 to 67_4 and the switch circuits 68_1 to 68_4 are examples, and those voltages It is not limited to the value. Needless to say, the cartridge 100 can output a DC voltage and an AC voltage independently even when the cartridge 100 is detached from the power storage system 6.

DESCRIPTION OF SYMBOLS 2 ... Electric power meter, 3 ... Power distribution apparatus, 4 ... Power management apparatus, 4a ... Control apparatus, 4b ... Operation panel, 5 ... Power supply monitor, 6 ... Power storage system, 60 ... Power storage apparatus, 61a ... Bidirectional DC-DC converter, 61b ... Bidirectional DC-AC inverter, 62 ... Control circuit, 65_1, 65_2, 65_3, 65_4 ... Cross current prevention circuit, 66_1, 66_2, 66_3, 66_4, 69_1, 69_2, 69_3, 69_4 ... Diode, 67_1, 67_2, 67_3 67_4, 68_1, 68_2, 68_3, 68_4 ... switch circuit, 101 ... cell, 102 ... safety circuit, 103 ... handle, 111_1, 111_2, 111_3, 111_4 ... + terminal, 112_1, 112_2, 112_3, 112_4 ...- terminal

Claims (12)

Connect multiple cartridges consisting of connected cells in parallel,
A cross current prevention circuit for limiting the current to each of the cartridges in one direction of discharging or charging;
A power storage device characterized in that a commercial voltage is converted into a DC voltage and simultaneously charged for the plurality of cartridges connected in parallel, or the commercial voltage is output by discharging simultaneously from the plurality of cartridges connected in parallel. system. Provided in common for a plurality of cartridges connected in parallel, convert the commercial voltage to a DC voltage and charge them simultaneously for a plurality of cartridges connected in parallel, or discharge them simultaneously from a plurality of cartridges connected in parallel A power conditioner that outputs commercial voltage;
A cross current prevention circuit including a diode and a switch circuit that limits a current to each of the cartridges in one direction of discharging or charging; and
The power storage system according to claim 1, further comprising: a control circuit that controls conduction or non-conduction of the switch circuit configuring the plurality of cross current prevention circuits. The cross current prevention circuit includes a first diode and a first switch circuit connected in series to form a current path only in a discharge direction with respect to each of the cartridges,
The power storage system according to claim 2, further comprising: a second diode and a second switch circuit connected in series that form a current path only in a charging direction with respect to each of the cartridges. When the control circuit receives a discharge instruction signal instructing discharge from the power storage system,
For a plurality of cartridges connected in parallel, the first switch circuit that forms a current path only in the discharge direction is simultaneously conducted,
The power storage system according to claim 3, wherein the commercial voltage is output until a sustain voltage of the plurality of cartridges reaches a first voltage. When the control circuit receives a charge instruction signal instructing charging of the power storage system,
For a plurality of cartridges connected in parallel, the second switch circuit that forms a current path only in the charging direction is simultaneously conducted,
5. The power storage system according to claim 4, wherein charging is performed in accordance with the commercial voltage until a maintenance voltage of the cartridge reaches a second voltage. The control circuit is a cartridge extraction signal that indicates that the user intends to extract any one of the plurality of cartridges connected in parallel when the discharge instruction signal is input. Is entered,
If the cartridge is being discharged, a signal indicating that the cartridge can be extracted is output to the cartridge by turning off the first switch circuit that forms a current path only in the discharge direction. The power storage system according to any one of claims 4 and 5, wherein: The control circuit is a cartridge extraction signal that indicates that the user intends to extract one of the plurality of cartridges connected in parallel when the charge instruction signal is input Is entered,
If the cartridge is being charged, a signal indicating that the cartridge can be removed is output to the cartridge by turning off the second switch circuit that forms a current path only in the charging direction. The power storage system according to any one of claims 4 to 6, wherein:   The connection portion between the power storage system and the cartridge is provided with a cover on the power storage system and the cartridge side, and when the cartridge is fitted into the power storage system, the connection portion is exposed to form an electrical connection. The electrical storage system of any one of Claims 7.   The connection part between the power storage system and the cartridge is provided with a wireless power transfer device on the power storage system and the cartridge side, and power can be exchanged without being physically connected. The power storage system according to any one of 8.   Claims 1 to 9 that can be diverted to general houses, stores, buildings, factories, backup power sources, mega solar power storage, wind power storage, geothermal power generation power storage, electric vehicles, plug-in hybrid vehicles, and hybrid vehicles. The electrical storage system of any one of them.   The storage system is connected to the LAN, and the future solar cell power generation amount is calculated based on the weather forecast. As a result, the period during which the solar cell power generation amount is more than half of the rated output is determined in advance. If it is less than the specified time, the solar battery output amount is predicted from the weather forecast, and the future solar cell power generation amount is calculated based on the weather forecast. As a result, the solar cell power generation amount is half of the rated output. The power storage system according to any one of claims 1 to 10, wherein power storage from the system is not performed if the above period is equal to or longer than the predetermined time.   A cartridge capable of outputting a DC voltage and an AC voltage independently even if it is detached from the power storage system according to any one of claims 1 to 11.

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