JP2013031310A - Control device, battery system, electric vehicle, mobile body, power storage device, and power supply device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control device, a battery system, an electric vehicle, a mobile body, a power storage device and a power supply device which can extend the life of a battery cell.SOLUTION: A charge of electricity by input power from a power input unit IN to at least one of a main battery module 100 and an auxiliary battery module 200 is controlled by a battery ECU 300 so that the SOC of a main battery module 100 follows an SOC expected value function which changes in a time axis direction. On the other hand, supply of electric power by a discharge of at least one of the main battery module 100 and the auxiliary battery module 200 is controlled by the battery ECU 300. Furthermore, a charge and a discharge of electricity to and from the main battery module 100 and the auxiliary battery module 200 are controlled by the battery ECU 300 so that the SOC of the main battery module 100 follows the SOC expected value function.

Description

  The present invention relates to a control device, a battery system including the control device, an electric vehicle, a moving body, a power storage device, and a power supply device.

  A battery system including a chargeable / dischargeable battery cell is used for a moving body such as an electric automobile or a power supply device that stores electric power. It is known that the lifetime of such a battery cell changes depending on how it is used. Patent Document 1 describes a power supply device control method for an electric vehicle for extending the life of a secondary battery.

  In the power supply device control method described in Patent Document 1, a power supply device including a main power supply and a sub power supply is connected to a load device. The main power supply supplies current at a set constant value. Here, when the current required by the load device is less than the current supplied from the main power supply, the difference current is supplied to the sub-power supply. In this case, the sub power supply is charged. On the other hand, when the current required by the load device is larger than the current supplied from the main power supply, the difference current is supplied by the sub power supply. In this case, the sub power supply is discharged.

Japanese Patent Laid-Open No. 10-80008

  In the power supply device control method of Patent Document 1, it is described that the life of the main power supply can be extended by suppressing a rapid change in supply current. It is known that a secondary battery such as a lithium ion battery has a life (cycle life) that deteriorates by repeatedly charging and discharging and a life (calendar life) that deteriorates by maintaining a high charge state. However, in the power supply device control method disclosed in Patent Document 1, when the current required by the load device frequently changes, the frequency of charging and discharging the battery cells increases. Further, when no current is supplied to the load device for a long time, the battery cell is kept in a high charged state for a long time. Therefore, the life of the main power source cannot be extended due to the limitation of the cycle life or the calendar life.

  An object of the present invention is to provide a control device, a battery system, an electric vehicle, a moving body, a power storage device, and a power supply device that can extend the life of a battery cell.

  The battery system according to the present invention follows a main function including a battery cell, an auxiliary battery module connected to the main battery module, and a target function in which the state of charge of the main battery module changes in a preset time axis direction. To control the charging of at least one of the main battery module and the auxiliary battery module by power supplied from the outside, and to control the supply of power to the external load by discharging at least one of the main battery module and the auxiliary battery module And a controller for controlling charging and discharging between the main battery module and the auxiliary battery module.

  The state of charge here is defined by, for example, SOC (State of Charge) represented by the ratio of the remaining capacity to the full charge capacity. That is, the target function means a function having time as a variable and giving an SOC value.

  The change in the time axis direction of the target function means, for example, a change between the value of the target function at a certain first time point and the value of the target function at the subsequent second time point. The change in the time axis direction includes a periodic change. The periodical change only needs to include at least one period of change, and the periods do not have to have the same time width.

  According to the present invention, the life of the battery cell can be prolonged.

It is a block diagram which shows the structure of the battery system which concerns on 1st Embodiment. It is a flowchart which shows control of the electric power supply of a battery system. It is a flowchart which shows control of the electric power supply of a battery system. It is a flowchart which shows control of the electric power supply of a battery system. It is a flowchart which shows control of the electric power supply of a battery system. It is a flowchart which shows control of the electric power supply of a battery system. It is a figure which shows the result of the simulation of SOC of the main battery module and auxiliary battery module in a 1st control example. It is a figure which shows the result of the simulation of SOC of the main battery module and auxiliary battery module in a 2nd control example. It is a figure which shows the result of the simulation of SOC of the main battery module and auxiliary battery module in a 3rd control example. It is a block diagram which shows the structure of an electric vehicle provided with a battery system. It is a block diagram which shows the structure of a power supply device provided with a battery system.

  A battery system according to an embodiment of the present invention includes a main battery module including battery cells, an auxiliary battery module connected to the main battery module, and a state of charge of the main battery module that changes in a preset time axis direction. And controlling charging of at least one of the main battery module and the auxiliary battery module by electric power supplied from the outside so as to follow the target function to be performed, and discharging to at least one of the main battery module and the auxiliary battery module to an external load While controlling supply of electric power, the control apparatus which controls charge and discharge between a main battery module and an auxiliary battery module is provided.

  In this battery system, the control device controls charging of at least one of the main battery module and the auxiliary battery module with electric power supplied from the outside so that the charging state of the main battery module follows a target function that changes in the time axis direction. Controlled by In addition, the control device controls the supply of electric power to an external load by discharging at least one of the main battery module and the auxiliary battery module so that the charging state of the main battery module follows a target function that changes in the time axis direction. The Furthermore, charging and discharging between the main battery module and the auxiliary battery module are controlled by the control device so that the charging state of the main battery module follows a target function that changes in the time axis direction.

  Therefore, it is possible to supply power to an external load while making the state of charge of the main battery module follow the target function. In this case, by appropriately setting the target function, the charge / discharge frequency of the main battery module can be controlled regardless of the state of power supply to the external load. Thereby, deterioration of the main battery module due to cycle life can be alleviated.

  In addition, by appropriately setting the target function, it is possible to prevent the main battery module from being maintained for a long time in a high charge state or a low charge state. Thereby, deterioration of the main battery module due to the calendar life can be alleviated. As a result, the life of the main battery module can be extended.

  Furthermore, by appropriately setting the target function, the state of charge of the main battery module is temporarily set to a predetermined value while supplying power to the external load by the auxiliary battery module, and the main battery in a predetermined period. The state of charge of the module can be made to follow a specific target function. Thereby, it becomes possible to contribute to the improvement of the measurement accuracy of the state of charge of the main battery module.

  The control device is based on the comparison result between the target function and the state of charge of the main battery module, and at least one of the power supplied from the outside, the power required from the external load, and the power stored in the auxiliary battery module. The charging and discharging of the main battery module and the auxiliary battery module may be controlled.

  In this case, based on the comparison result between the target function and the state of charge of the main battery module, and at least one of the power supplied from the outside, the power required from the external load, and the power stored in the auxiliary battery module The main battery module is charged by the power supplied from the outside or the auxiliary battery module, or the main battery module is discharged to supply power to the external load or the auxiliary battery module. As a result, the required power can be supplied to the external load while the charging state of the main battery module reliably follows the target function.

  The control device may selectively perform charging of the main battery module by discharging the auxiliary battery module and charging of the auxiliary battery module by discharging the main battery module based on the target function.

  In this case, part or all of the power for charging the main battery module is supplied by discharging the auxiliary battery module. Thereby, for example, even when power is not supplied from the outside, the main battery module can be charged. Further, part or all of the power for charging the auxiliary battery module is supplied by discharging the main battery module. Thereby, for example, even when electric power is not supplied from the outside, the auxiliary battery module can be charged. Therefore, when power is not supplied to an external load, power can be stored in the main battery module and the auxiliary battery module without wasting power.

  When the state of charge of the main battery module is smaller than the target function value, the control device externally controls the main battery module to be charged by at least one of power supplied from the outside and power supplied from the auxiliary battery module. And the power supply from the auxiliary battery module is controlled, and when the state of charge of the main battery module is larger than the value of the target function, the main battery module is supplied by supplying power to an external load and / or the auxiliary battery module. You may control supply of the electric power to an external load and an auxiliary battery module so that it may be discharged.

  According to this control, when the state of charge of the main battery module is smaller than the value of the target function, the main battery module is charged with at least one of power supplied from the outside and power supplied from the auxiliary battery module. Thereby, the main battery module can be charged. When the state of charge of the main battery module is larger than the target function value, the main battery module is discharged by supplying power to at least one of the external load and the auxiliary battery module. Thereby, the main battery module can be discharged without wasting power.

  When the power supplied from the outside is larger than the power required from the external load and the state of charge of the main battery module is larger than the value of the target function, the control device The power supply from the outside and the main battery module is controlled so that the auxiliary battery module is charged by at least one of the power supplied from the outside, and the power supplied from the outside is smaller than the power required from the external load. Or when the state of charge of the main battery module is smaller than the value of the target function, the external battery and the main battery module are discharged so that the auxiliary battery module is discharged by supplying power to at least one of the external load and the main battery module. You may control supply of the electric power to a battery module.

  In this case, the auxiliary battery module is charged with at least one of the electric power supplied from the outside and the main battery module. Further, the auxiliary battery module is discharged by supplying power to at least one of the external load and the main battery module. Thereby, the auxiliary battery module can be charged and discharged while the charging state of the main battery module follows the target function.

  A control device according to another embodiment of the present invention is connected to a main battery module including battery cells and an auxiliary battery module connected to the main battery module, and is set in advance to change in the time axis direction. A storage unit that stores a target function of the charging state of the module, and controls charging of at least one of the main battery module and the auxiliary battery module by power supplied from the outside so that the charging state of the main battery module follows the target function A power control unit for controlling power supply to an external load due to discharge of at least one of the main battery module and the auxiliary battery module and for controlling charging and discharging between the main battery module and the auxiliary battery module. It is to be prepared.

  According to this control device, at least one of the main battery module and the auxiliary battery module using electric power supplied from the outside so that the state of charge of the main battery module follows a target function that changes in the time axis direction stored in the storage unit. One charging is controlled by the power supply controller. In addition, power is supplied to an external load by discharging at least one of the main battery module and the auxiliary battery module so that the state of charge of the main battery module follows a target function that changes in the time axis direction stored in the storage unit. Is controlled by the power supply controller. Furthermore, charging and discharging between the main battery module and the auxiliary battery module are controlled by the control device so that the charging state of the main battery module follows a target function that changes in the time axis direction stored in the storage unit. .

  Therefore, it is possible to supply power to an external load while making the state of charge of the main battery module follow the target function. In this case, by appropriately setting the target function, the charge / discharge frequency of the main battery module can be controlled regardless of the state of power supply to the external load. Thereby, deterioration of the main battery module due to cycle life can be alleviated.

  In addition, by appropriately setting the target function, it is possible to prevent the main battery module from being maintained for a long time in a high charge state or a low charge state. Thereby, deterioration of the main battery module due to the calendar life can be alleviated. As a result, the life of the main battery module can be extended.

  Furthermore, by appropriately setting the target function, the state of charge of the main battery module is temporarily set to a predetermined value while supplying power to the external load by the auxiliary battery module, and the main battery in a predetermined period. The state of charge of the module can be made to follow a specific target function. Thereby, it becomes possible to contribute to the improvement of the measurement accuracy of the state of charge of the main battery module.

  An electric vehicle according to still another embodiment of the present invention includes the battery system, a motor driven by electric power from a main battery module of the battery system, and driving wheels that rotate by the rotational force of the motor. is there.

  In this electric vehicle, the motor is driven by the electric power from the main battery module. The drive wheel is rotated by the rotational force of the motor, so that the electric vehicle moves.

  Since the battery system is used for this electric vehicle, the life of the main battery module of the electric vehicle can be extended. Therefore, the reliability and cost reduction of the electric vehicle can be achieved.

  A moving body according to still another embodiment of the present invention includes the battery system, a moving main body, and a power source that converts electric power from the main battery module of the battery system into power for moving the moving main body. And a drive unit that moves the moving main body by the power converted by the power source.

  In this moving body, the electric power from the battery system is converted into power by a power source, and the drive unit moves the moving main body by the power.

  Since the battery system is used for the moving body, the life of the main battery module of the moving body can be extended. Therefore, it is possible to improve the reliability of the moving body and reduce the cost.

  A power storage device according to still another embodiment of the present invention includes the battery system and a system control unit that performs control related to charging or discharging of a main battery module of the battery system.

  In this power storage device, control related to charging or discharging of the main battery module is performed by the system control unit. Thereby, deterioration, overdischarge and overcharge of the main battery module can be prevented.

  Since the battery system is used for the power storage device, the life of the main battery module of the power storage device can be extended. Therefore, it is possible to improve the reliability and reduce the cost of the power storage device.

  A power supply device according to still another embodiment of the present invention is connectable to the outside, and is controlled by the power storage device and a system control unit of the power storage device, and is a main battery module of a battery system of the power storage device. And a power conversion device that performs power conversion with the outside.

  In this power supply device, power conversion is performed between the main battery module and the outside by the power conversion device. Control related to charging or discharging of the main battery module is performed by controlling the power conversion device by the system control unit of the power storage device. Thereby, deterioration, overdischarge and overcharge of the main battery module can be prevented.

  Since the battery system is used for the power supply device, the life of the main battery module of the power supply device can be extended. Therefore, it is possible to improve the reliability and reduce the cost of the power supply device.

[1] First Embodiment A battery system according to a first embodiment will be described below with reference to the drawings. The battery system is mounted on a moving body such as an electric vehicle that uses electric power as a drive source, or a power supply apparatus having an electric power storage device. In addition, the battery system can be mounted on a consumer device or the like including a battery cell that can be charged and discharged.

(1) Configuration of Battery System FIG. 1 is a block diagram showing the configuration of the battery system according to the first embodiment. The battery system 500 according to the first embodiment includes a main battery module 100, an auxiliary battery module 200, and a battery ECU (Electronic Control Unit) 300. The battery system 500 includes a power input unit IN and a power output unit OUT. Further, the battery system 500 may include a battery management function such as state monitoring and protection of the main battery module 100. In this embodiment, the main battery module 100 and the auxiliary battery module 200 are connected in parallel.

  Main battery module 100 includes a plurality of battery cells 10. In the main battery module 100, the plurality of battery cells 10 are connected in series. The main battery module 100 may include a plurality of battery cells 10 connected in parallel, or may include a plurality of battery cells 10 connected in series and connected in parallel. The main battery module 100 may include a battery pack including a plurality of battery cells 10 connected in series and in parallel. Further, the main battery module 100 may include a single battery cell 10. Each battery cell 10 is a secondary battery. In this embodiment, a lithium ion battery is used as the secondary battery. In the present embodiment, a plurality of battery cells 10 connected in series constitute a battery module. The main battery module 100 is connected to the auxiliary battery module 200, the power input unit IN, and the power output unit OUT in a chargeable / dischargeable manner. The main battery module 100 performs charge / discharge based on control by the battery ECU 300.

  The auxiliary battery module 200 is a chargeable / dischargeable large capacity capacitor such as an electric double layer capacitor. A lead storage battery may be used as the auxiliary battery module 200. Further, as the auxiliary battery module 200, a battery module having the same configuration as that of the main battery module 100 may be used. The auxiliary battery module 200 is connected to the main battery module 100, the power input unit IN, and the power output unit OUT in a chargeable / dischargeable manner. The auxiliary battery module 200 performs charging / discharging based on control by the battery ECU 300.

  The battery ECU 300 includes, for example, a CPU (Central Processing Unit) 310, a memory 320, and the like. Battery ECU 300 may be a microcomputer. Battery ECU 300 is communicably connected to main battery module 100, auxiliary battery module 200, power input unit IN, and power output unit OUT via bus BS. The battery ECU 300 performs control related to charging / discharging of at least one of the main battery module 100 and the auxiliary battery module 200. In this embodiment, control related to charging / discharging of both the main battery module 100 and the auxiliary battery module 200 is performed.

  The power input unit IN is, for example, a charging circuit. The power output unit OUT is a power supply circuit for supplying power to a load such as a mobile phone, a personal computer or a motor of an electric vehicle, a home appliance, an indoor facility, a factory facility, or a stationary power storage device. Electric power from a commercial power source or a solar cell is input to the power input unit IN. Regenerative power of the electric vehicle may be input to the power input unit IN. Hereinafter, the power input to the power input unit IN is referred to as input power. The power input unit IN has a function of supplying power to the main battery module 100, the auxiliary battery module 200, and the power output unit OUT based on the input power. The power output unit OUT outputs the supplied power to the load. The power output from the power output unit OUT is hereinafter referred to as output power. In this embodiment, DC (direct current) power is supplied from the power input unit IN. DC power is input to the power output unit OUT. DC or AC (alternating current) power is supplied from the power output unit OUT. The power output unit OUT may include a DC / DC (direct current / direct current) converter or a DC / AC (direct current / alternating current) converter. The power input unit IN and the power output unit OUT may be configured as one power input / output unit having a power input function and an output function.

  In the following description, supplying power to the main battery module 100 from the power input unit IN or the auxiliary battery module 200 means charging the main battery module 100. Supplying power to the auxiliary battery module 200 by the power input unit IN or the main battery module 100 means charging the auxiliary battery module 200. Further, supplying power to the auxiliary battery module 200 or the power output unit OUT by the main battery module 100 means discharging the main battery module 100. Supplying power to the main battery module 100 or the power output unit OUT by the auxiliary battery module 200 means that the auxiliary battery module 200 is discharged.

  In FIG. 1, power supply from the power input unit IN to the main battery module 100, the auxiliary battery module 200, and the power output unit OUT is indicated by arrows a, b, and c, respectively. Supply of power from the main battery module 100 and the auxiliary battery module 200 to the power output unit OUT is indicated by arrows d and e, respectively. The supply of power from the main battery module 100 to the auxiliary battery module 200 is indicated by an arrow f, and the supply of power from the auxiliary battery module 200 to the main battery module 100 is indicated by an arrow g. Input power is indicated by an arrow h, and output power is indicated by an arrow i.

  In this battery system 500, the main battery module 100 and the auxiliary battery using the power supplied from the power input unit IN so as to follow a later-described SOC expected value function in which the state of charge of the main battery module 100 changes in the time axis direction. Charging of at least one of the modules 200 is controlled by the battery ECU 300. In addition, supply of power to the power output unit OUT by discharging at least one of the main battery module 100 and the auxiliary battery module 200 so that the state of charge of the main battery module 100 follows an expected SOC function that changes in the time axis direction. Is controlled by the battery ECU 300. Further, charging and discharging between the main battery module 100 and the auxiliary battery module 200 are controlled by the battery ECU 300 so that the state of charge of the main battery module 100 follows an SOC expected value function that changes in the time axis direction.

  The change in the time axis direction of the SOC expected value function is, for example, a change between the value of the SOC expected value function at a certain first time point and the value of the SOC expected value function at the subsequent second time point. means. The periodical change only needs to include at least one period of change, and the periods do not have to have the same time width. In this embodiment, an example in which the SOC expected value function periodically changes will be described as an example of the change in the time axis direction.

  Therefore, it is possible to supply power to the power output unit OUT while making the state of charge of the main battery module 100 follow the SOC expected value function. In this case, by appropriately setting the SOC expected value function, the charge / discharge frequency of the main battery module 100 can be controlled regardless of the power supply state of the power output unit OUT. Thereby, deterioration of the main battery module 100 due to cycle life can be alleviated.

  Further, by appropriately setting the SOC expected value function, it is possible to prevent the main battery module 100 from being maintained for a long time in a high charge state or a low charge state. Thereby, deterioration of the main battery module 100 due to the calendar life can be alleviated. As a result, the life of the main battery module 100 can be extended.

  Furthermore, by appropriately setting the SOC expected value function, it is possible to temporarily set the charging state of the main battery module 100 to a predetermined value while supplying power to the power output unit OUT by the auxiliary battery module 200. Thereby, it becomes possible to contribute to the improvement of the measurement accuracy of the state of charge of the main battery module 100.

(2) SOC Expected Value Function In the following description, the amount of charge accumulated in the main battery module 100 in the fully charged state is referred to as the full charge capacity. The amount of charge stored in the main battery module 100 in an arbitrary state is called the remaining capacity. The ratio of the remaining capacity to the full charge capacity of the main battery module 100 is referred to as a charging rate (SOC). The state of charge includes SOC, open-circuit voltage, remaining capacity, depth of discharge, accumulated current value, difference in charged amount, etc. In this embodiment, the SOC of main battery module 100 is an example of the state of charge of main battery module 100. Is used.

  In the battery system 500 of FIG. 1, the SOC of the main battery module 100 can be changed following the preset change pattern by the control described below. A preset SOC change pattern is called an SOC expected value function, and an SOC value at each point of the SOC expected value function is called an SOC expected value. The expected SOC value is a target value of the SOC. The SOC expected value function is an expected value function of the SOC target value that changes in the time axis direction. The SOC expected value function is stored in memory 320 of battery ECU 300. In the present embodiment, the SOC expected value function is a sine wave (sine curve), but may be a square wave or another waveform. Further, the SOC expected value function may change into a sine wave, a square wave, or another waveform in terms of time. Furthermore, the SOC expected value function may have a period during which the target value is set to zero. The period of the SOC expected value function may be constant, or each period in the SOC expected value function may change.

  CPU 310 of battery ECU 300 (hereinafter simply referred to as battery ECU 300) compares the SOC of main battery module 100 with the expected SOC value of the expected SOC function. When the SOC of the main battery module 100 is smaller than the expected SOC value, the battery ECU 300 causes the power input unit to charge the main battery module 100 with at least one of the power supplied from the power input unit IN and the auxiliary battery module 200. The power supply from the IN and auxiliary battery module 200 is controlled.

  On the other hand, when the SOC of main battery module 100 is larger than the expected SOC value, battery ECU 300 supplies power so that main battery module 100 is discharged by supplying power to at least one of power output unit OUT and auxiliary battery module 200. The power supply to the output unit OUT and the auxiliary battery module 200 is controlled.

  Battery ECU 300 also compares the input power from power input unit IN with the output power to power output unit OUT. When the input power is greater than the output power and the SOC of the main battery module 100 is greater than the expected SOC value, the battery ECU 300 causes the auxiliary battery module 200 to use at least one of the power input from the power input unit IN and the main battery module 100. Is controlled to supply power from the power input section IN and the main battery module 100. On the other hand, battery ECU 300 supplies power to at least one of power output unit OUT and main battery module 100 when the input power is smaller than the output power or when the SOC of main battery module 100 is smaller than the expected SOC value. Thus, the supply of power to the power output unit OUT and the main battery module 100 is controlled so that the auxiliary battery module 200 is discharged.

(3) Operation of Battery ECU FIGS. 2 to 6 are flowcharts showing control of power supply of the battery system 500. Hereinafter, control of power supply of the battery system 500 by the battery ECU 300 will be described with reference to FIGS. 1 and 2 to 6. 2 is connected to the connector A in FIG. The connector B in FIG. 2 is connected to the connector B in FIG. The connector C in FIG. 3 is connected to the connector C in FIG. The connector D in FIG. 2 is connected to the connector D in FIG. The connector E in FIG. 4 is connected to the connector E in FIG. The connector F in FIG. 5 is connected to the connector F in FIG. The connector G in FIG. 5 is connected to the connector G in FIG. The connector H in FIG. 6 is connected to the connector H in FIG. The connector I in FIG. 4 and the connector I in FIG. 5 are connected to the connector I in FIG.

  First, the battery ECU 300 determines whether or not the input power to the power input unit IN is greater than or equal to the output power from the power output unit OUT (step S1). When the input power is equal to or higher than the output power, all the power required from the load connected to the power output unit OUT can be supplied from the power input unit IN. In this case, battery ECU 300 performs the following plurality of processes (steps S2, S3, S4, and S7) in parallel.

  When the input power is greater than or equal to the output power in step S1, the power input unit IN can supply sufficient power. Therefore, as indicated by an arrow c in FIG. 1, as one of the parallel processes, the battery ECU 300 supplies power from the power input unit IN to the power output unit OUT (step S2). Thereby, the input power to the power input unit IN is supplied to the load connected to the power output unit OUT.

  Further, when the input power is equal to or higher than the output power in step S1, power is not supplied from the main battery module 100 to the power output unit OUT. Therefore, as one of the parallel processes, the battery ECU 300 stops supplying power from the main battery module 100 to the power output unit OUT (step S3).

  Further, when the input power is greater than or equal to the output power in step S1, as one of the parallel processes, the battery ECU 300 causes the SOC of the main battery module 100 to be less than the SOC expected value of the SOC expected value function and for a predetermined time. It is determined whether or not the SOC of main battery module 100 does not reach 100% after Δt (step S4 via connector A). Note that the SOC after the predetermined time Δt is a predicted value from the present time. The same applies to the following description. In this embodiment, the predetermined time Δt is set to, for example, about 0.1 seconds to 1 second. The range of the predetermined time Δt is not limited to 0.1 second to 1 second. The range of the predetermined time Δt can be appropriately set by a trade-off between the accuracy of processing by the battery ECU 300 and the performance of the CPU 310 of the battery ECU 300 that performs the processing.

  If the SOC of the main battery module 100 is less than the expected SOC value and the SOC of the main battery module 100 does not reach 100% after the predetermined time Δt in step S4, the SOC of the main battery module 100 follows the expected SOC value. The battery module 100 is charged. Therefore, as shown by an arrow a in FIG. 1, the battery ECU 300 supplies power from the power input unit IN to the main battery module 100 (step S5). Thereby, the main battery module 100 is charged.

  On the other hand, when the SOC of the main battery module 100 is equal to or higher than the expected SOC value in step S4, or when the SOC of the main battery module 100 reaches 100% after a predetermined time Δt, the main battery module 100 is not charged. Therefore, battery ECU 300 stops supplying power from power input unit IN to main battery module 100 (step S6).

  If the input power is greater than or equal to the output power in step S1, power is not supplied from the auxiliary battery module 200 to the power output unit OUT. Therefore, as one of the parallel processes, the battery ECU 300 stops supplying power from the auxiliary battery module 200 to the power output unit OUT (step S7 via the connector A).

  In the present embodiment, battery ECU 300 simultaneously executes the process of step S2, the process of step S3, the process of step S5 or step S6 via step S4, and the process of step S7. The process of simultaneously executing the process of step S2, the process of step S3, the process of step S5 or step S6, and the process of step S7 is referred to as a first process.

  On the other hand, when the input power is less than the output power in step S1, all of the power required from the load connected to the power output unit OUT cannot be supplied from the power input unit IN. In this case, for example, the battery ECU 300 performs the following plurality of processes (steps S8, S9, S6, S11) in parallel.

  When the input power is less than the output power in step S1, the power input unit IN cannot supply sufficient power. Therefore, as one of the parallel processes, the battery ECU 300 stops the supply of power from the power input unit IN to the power output unit OUT (step S8).

  When the input power is less than the output power in step S1, as one of the parallel processes, the battery ECU 300 causes the main battery module 100 to exceed the SOC expected value of the SOC expected value function and the main battery after a predetermined time Δt. It is determined whether or not the SOC of the module 100 does not decrease to 0% (step S9).

  In step S9, if the SOC of the main battery module 100 exceeds the SOC expected value and the SOC of the main battery module 100 does not decrease to 0% after a predetermined time Δt, the SOC of the main battery module 100 follows the expected SOC value. The battery module 100 is discharged. Therefore, as shown by the arrow d in FIG. 1, the battery ECU 300 supplies power from the main battery module 100 to the power output unit OUT (step S10). Thereby, the main battery module 100 is discharged, and the power from the main battery module 100 is supplied to the load connected to the power output unit OUT.

  On the other hand, when the SOC of the main battery module 100 is equal to or lower than the expected SOC value in step S9, or when the SOC of the main battery module 100 decreases to 0% after a predetermined time Δt, the main battery module 100 cannot be discharged. Therefore, battery ECU 300 stops the supply of power from main battery module 100 to power output unit OUT (step S3).

  Furthermore, when the input power is less than the output power in step S1, the power input unit IN cannot supply sufficient power. Therefore, as one of the parallel processes, the battery ECU 300 stops the supply of power from the power input unit IN to the main battery module 100 (step S6 via the connector B).

  When the input power is less than the output power in step S1, as one of the parallel processes, the battery ECU 300 determines whether or not the SOC of the auxiliary battery module 200 does not decrease to 0% after a predetermined time Δt (connector) Step S11) via B.

  If the SOC of the auxiliary battery module 200 does not decrease to 0% after the predetermined time Δt in step S11, the auxiliary battery module 200 can supply sufficient power. Therefore, as shown by an arrow e in FIG. 1, the battery ECU 300 supplies power from the auxiliary battery module 200 to the power output unit OUT (step S12). As a result, the auxiliary battery module 200 is discharged, and power is supplied from the auxiliary battery module 200 to the load connected to the power output unit OUT.

  On the other hand, when the SOC of the auxiliary battery module 200 decreases to 0% after the predetermined time Δt in step S11, the auxiliary battery module 200 cannot supply sufficient power. Therefore, battery ECU 300 stops the supply of power from auxiliary battery module 200 to power output unit OUT (step S7).

  In the present embodiment, battery ECU 300 executes step S8, step S10 or step S3, step S6, and step S12 or step S7 simultaneously. The process of step S8, the process of step S10 or step S3 via step S9, the process of step S6, and the process of step S12 or step S7 are executed simultaneously.

  Battery ECU 300 waits for a predetermined time Δt after the first process or the second process (step S13 and step S13 via connector C). Thereafter, the battery ECU 300 returns to the process of step S1 and proceeds to the process of step S14 in FIG. The process after step S1 performed after the process of step S13 is hereinafter referred to as the second and subsequent processes.

  Battery ECU 300 executes the processes of steps S1 to S13 in the second and subsequent rounds, and determines whether or not the input power to power input unit IN is equal to or higher than the output power from power output unit OUT (connector D Through step S14). In the present embodiment, battery ECU 300 simultaneously performs the process in step S1 and the process in step S14 for the second and subsequent rounds. When the input power is equal to or higher than the output power, all the power required from the load connected to the power output unit OUT can be supplied from the power input unit IN.

  When the input power is greater than or equal to the output power in step S14, the power input unit IN can supply sufficient power. In this case, the battery ECU 300 determines whether or not the supply of power from the power input unit IN to the main battery module 100 is stopped (step S15).

  When the supply of power from the power input unit IN to the main battery module 100 is stopped in step S15, the SOC of the main battery module 100 is equal to or higher than the expected SOC value in step S4, or the main battery module 100 after the predetermined time Δt. The SOC of the battery module 100 reaches 100%. Therefore, the main battery module 100 is discharged. In this case, the battery ECU 300 determines whether the SOC of the auxiliary battery module 200 does not reach 100% after a predetermined time Δt (step S16).

  If the SOC of the auxiliary battery module 200 does not reach 100% after the predetermined time Δt in step S16, the auxiliary battery module 200 can be charged. Therefore, as shown by the arrow b in FIG. 1, the battery ECU 300 supplies power from the power input unit IN to the auxiliary battery module 200 (step S17). Thereby, the auxiliary battery module 200 is charged. In the present embodiment, battery ECU 300 performs the first or second processing for the second and subsequent rounds and the processing in step S17 simultaneously.

  On the other hand, when the input power is less than the output power in step S14, the power input unit IN cannot supply sufficient power. Therefore, battery ECU 300 stops the supply of power from power input unit IN to auxiliary battery module 200 (step S18).

  If the supply of power from the power input unit IN to the main battery module 100 is not stopped in step S15, the main battery module 100 has an SOC less than the expected SOC value in the above step S4 and after a predetermined time Δt, the main battery The SOC of the module 100 will not reach 100%. Therefore, the main battery module 100 is charged. In this case, in order to charge the main battery module 100, the power input unit IN supplies power to the main battery module 100 as shown by an arrow a in FIG. Therefore, battery ECU 300 stops the supply of power from power input unit IN to auxiliary battery module 200 (step S18).

  Furthermore, when the SOC of the auxiliary battery module 200 reaches 100% after the predetermined time Δt in step S16, the auxiliary battery module 200 is not charged. Therefore, battery ECU 300 stops the supply of power from power input unit IN to auxiliary battery module 200 (step S18). In the present embodiment, battery ECU 300 performs the first or second processing after the second round and the processing in step S18 simultaneously.

  Battery ECU 300 waits for a predetermined time Δt after the process of step S17 or step S18 (step S13 via connector I). Thereafter, the battery ECU 300 returns to the process of step S1 after the second round and proceeds to the process of step S19 in FIG.

  The battery ECU 300 executes the processes of steps S1 to S18 in the second and subsequent rounds, and determines whether or not the supply of power from the power input unit IN to the main battery module 100 and the auxiliary battery module 200 is stopped ( Step S19) via connector E). When the supply of power from the power input unit IN to the main battery module 100 and the auxiliary battery module 200 is stopped, the input power is less than the output power in Step S1 and Step S14 described above. Therefore, the power input unit IN cannot supply sufficient power. In this case, battery ECU 300 performs the following plurality of processes (the processes of steps S20 and S23) in parallel.

  When the supply of power from the power input unit IN to the main battery module 100 and the auxiliary battery module 200 is stopped in step S19, as one of the parallel processes, the battery ECU 300 determines that the SOC of the main battery module 100 satisfies the SOC expected value. It is determined whether or not the SOC of the main battery module 100 does not decrease to 0% after the predetermined time Δt and the SOC of the auxiliary battery module 200 does not reach 100% after the predetermined time Δt (step S20).

  In step S20, the SOC of the main battery module 100 exceeds the SOC expected value, the SOC of the main battery module 100 does not decrease to 0% after a predetermined time Δt, and the SOC of the auxiliary battery module 200 reaches 100% after the predetermined time Δt. If not, the main battery module 100 is discharged in order to cause the SOC of the main battery module 100 to follow the expected SOC value. Moreover, the auxiliary battery module 200 can be charged. Therefore, as shown by the arrow f in FIG. 1, as one of the parallel processes, the battery ECU 300 supplies power from the main battery module 100 to the auxiliary battery module 200 (step S21). Here, the power supplied from the main battery module 100 to the auxiliary battery module 200 corresponds to the difference between the SOC of the main battery module 100 and the expected SOC value. Thereby, the main battery module 100 is discharged and the auxiliary battery module 200 is charged.

  On the other hand, if the SOC of the main battery module 100 is equal to or lower than the expected SOC value in step S20, the SOC of the main battery module 100 decreases to 0% after a predetermined time Δt, or the SOC of the auxiliary battery module 200 is 100 after the predetermined time Δt. When reaching%, the main battery module 100 is not discharged or the auxiliary battery module 200 is not charged. Therefore, battery ECU 300 stops supplying power from main battery module 100 to auxiliary battery module 200 (step S22).

  On the other hand, if the supply of power from the power input unit IN to both the main battery module 100 and the auxiliary battery module 200 is not stopped in step S19, the input power is greater than or equal to the output power in step S1 and step S14 described above. become. Therefore, the power input unit IN can supply sufficient power. Here, when the power input unit IN supplies power to the main battery module 100, the main battery module 100 cannot discharge. On the other hand, when the power input unit IN supplies power to the auxiliary battery module 200, the main battery module 100 does not supply power to the auxiliary battery module 200. Therefore, in any case, battery ECU 300 stops the supply of electric power from main battery module 100 to auxiliary battery module 200 (step S22).

  When the supply of power from the power input unit IN to the main battery module 100 and the auxiliary battery module 200 is stopped in step S19, the battery ECU 300 causes the SOC of the main battery module 100 to reach 100% after a predetermined time Δt. It is determined whether or not the SOC of the auxiliary battery module 200 does not decrease to 0% after a predetermined time Δt (step S23 via the connector F).

  If the SOC of the main battery module 100 does not reach 100% after the predetermined time Δt in step S23, and the SOC of the auxiliary battery module 200 does not decrease to 0% after the predetermined time Δt, the main battery module 100 is charged. Further, the auxiliary battery module 200 can supply sufficient power. Therefore, as shown by the arrow g in FIG. 1, the battery ECU 300 supplies power from the auxiliary battery module 200 to the main battery module 100 (step S24). Here, the electric power supplied from the main body 200 to the main battery module 100 corresponds to the difference between the SOC of the main battery module 100 and the expected SOC value. Thereby, the main battery module 100 is charged and the auxiliary battery module 200 is discharged.

  On the other hand, when the SOC of the main battery module 100 reaches 100% after the predetermined time Δt in step S23, or when the SOC of the auxiliary battery module 200 decreases to 0% after the predetermined time Δt, the main battery module 100 is not charged. Alternatively, the auxiliary battery module 200 cannot supply sufficient power. Therefore, battery ECU 300 stops the supply of electric power from auxiliary battery module 200 to main battery module 100 (step S25).

  In the present embodiment, the battery ECU 300 passes the first or second process after the second round, the process of step S17 or step S18 via steps S14 to S16 after the second round, and steps S19 and S20. The process of step S21 or step S22 and the process of step S24 or step S25 via step S23 are executed simultaneously. The process of simultaneously executing the process of step S21 or step S22 and the process of step S24 or step S25 is referred to as a third process.

  Further, when the supply of power from the power input unit IN to both the main battery module 100 and the auxiliary battery module 200 is not stopped in step S19, the input power is equal to or higher than the output power in step S1 and step S14 as described above. It will be. Therefore, the power input unit IN can supply sufficient power. Here, when the power input unit IN supplies power to the main battery module 100, the auxiliary battery module 200 does not supply power to the main battery module 100. On the other hand, when the power input unit IN supplies power to the auxiliary battery module 200, the auxiliary battery module 200 cannot discharge. Therefore, in any case, battery ECU 300 stops the supply of power from auxiliary battery module 200 to main battery module 100 (step S25 via connector G).

  In the present embodiment, battery ECU 300 simultaneously executes the first or second process after the second round, the process at step S17 or step S18 after the second round, the process at step S22, and the process at step S25. . The process of simultaneously executing the process of step S22 and the process of step S25 is referred to as a fourth process.

  The battery ECU 300 waits for a predetermined time Δt after the third process or the fourth process (step S13 via the connector I and the connectors H and I), and performs the process of step S1 after the second round. Return.

(4) First Control Example of SOC of Main Battery Module FIG. 7 is a diagram showing a simulation result of SOC of the main battery module 100 and the auxiliary battery module 200 in the first control example. In FIG. 7 and FIGS. 8 and 9 described later, the horizontal axis is time, and the vertical axis is SOC. In FIG. 7 and FIGS. 8 and 9 to be described later, the alternate long and two short dashes line indicates the change in the SOC expected value (SOC expected value function). An alternate long and short dash line indicates a change in the SOC of the main battery module 100 when the control by the battery ECU 300 is not performed. That is, FIGS. 7, 8, and 9 show the input power from the power input unit IN so that the change in the SOC of the main battery module 100 when the control by the battery ECU 300 is not performed becomes the change indicated by the alternate long and short dash line. This is an example assuming output power to the power output unit OUT. A dotted line indicates a change in the SOC of the auxiliary battery module 200. A solid line indicates a change in the SOC of the main battery module 100 when the control by the battery ECU 300 is performed.

  In the first control example, it is assumed that a regularly used load is connected to the power output unit OUT. The SOC expected value function is set so as to draw a sine curve when the SOC expected value is between 20% and 80%, as indicated by a two-dot chain line in FIG. The sine curve is set to have a low frequency that can prolong the cycle life of the main battery module 100 with respect to the input power from the power input unit IN and the output power to the power output unit OUT.

  When the SOC of the main battery module 100 is not controlled, power of at least one of the power input unit IN and the main battery module 100 is supplied to the power output unit OUT. As a result, as indicated by the one-dot chain line in FIG. Further, the power of the power input unit IN is supplied to the main battery module 100. As a result, as indicated by the alternate long and short dash line in FIG. 7, the main battery module 100 is charged in a short cycle until the SOC reaches 100%.

  As described above, when the control by the battery ECU 300 is not performed, the main battery module 100 is deteriorated by repeatedly charging and discharging the main battery module 100 in a short cycle between SOC 0% and 100%. Thereby, the cycle life of the main battery module 100 is shortened.

  On the other hand, when the SOC of the main battery module 100 is controlled, as shown by a solid line in FIG. 7, the main battery module 100 is configured so that the SOC of the main battery module 100 follows a change in the expected SOC value (an expected SOC function). 100 charging / discharging is performed.

  When the SOC of the main battery module 100 exceeds the SOC expected value, power corresponding to the difference between the SOC and the SOC expected value is supplied from the main battery module 100 to at least one of the power output unit OUT and the auxiliary battery module 200. . Further, the power of the power input unit IN is not supplied to the main battery module 100 but is supplied to at least one of the power output unit OUT and the auxiliary battery module 200. Thereby, the SOC of the main battery module 100 follows the change of the SOC expected value (SOC expected value function), and desired power is supplied to the power output unit OUT.

  When the SOC of the main battery module 100 is less than the expected SOC value, power corresponding to the difference between the SOC and the expected SOC value is supplied to the main battery module 100 from at least one of the power input unit IN and the auxiliary battery module 200. The Moreover, the power of the main battery module 100 is not supplied to the power output unit OUT, and at least one of the power input unit IN and the auxiliary battery module 200 is supplied to the power output unit OUT. Thereby, the SOC of the main battery module 100 follows the change of the SOC expected value (SOC expected value function), and desired power is supplied to the power output unit OUT.

  In the first control example, the SOC expected value function is set so that the SOC expected value changes between 20% and 80% and a rapid change is suppressed. Therefore, the SOC of main battery module 100 is limited to between 20% and 80%, and the frequency of charging / discharging of main battery module 100 is reduced. Thereby, the cycle life of the main battery module 100 is prolonged. In the first control example, the SOC of the main battery module 100 is set to a predetermined value (for example, less than 80%). Therefore, main battery module 100 is not maintained for a long time in a state where the SOC is as high as 80% or more. Thereby, the calendar life of the main battery module 100 is prolonged. As a result, the life of the main battery module 100 can be extended.

(5) Second Control Example of SOC of Main Battery Module FIG. 8 is a diagram illustrating a result of SOC simulation of the main battery module 100 and the auxiliary battery module 200 in the second control example.

  In the second control example, it is assumed that a low-use load is connected to the power output unit OUT. In this case, since the frequency with which power is supplied from the main battery module 100 to the power output unit OUT is low, the main battery module 100 is charged until the SOC of the main battery module 100 is 80% or more, as shown by a one-dot chain line in FIG. Maintained.

  As described above, when the control by the battery ECU 300 is not performed, the main battery module 100 is deteriorated by maintaining a high SOC state (for example, 80% or more). Thereby, the calendar life of the main battery module 100 is shortened.

  On the other hand, the SOC expected value function is set so as to draw a sine curve between the SOC expected value of 15% and 85%, as indicated by a two-dot chain line in FIG. Therefore, when the SOC of the main battery module 100 is controlled, as shown by a solid line in FIG. 8, the charging / discharging of the main battery module 100 is performed so that the SOC follows a change in the SOC expected value (SOC expected value function). Done.

  When the SOC of the main battery module 100 exceeds the SOC expected value, power corresponding to the difference between the SOC and the SOC expected value is supplied from the main battery module 100 mainly to the auxiliary battery module 200, and if necessary. It is also supplied to the power output unit OUT. Further, the power of the power input unit IN is not supplied to the main battery module 100, but is supplied mainly to the auxiliary battery module 200, and is also supplied to the power output unit OUT as necessary. Thereby, the SOC of the main battery module 100 follows the change of the SOC expected value (SOC expected value function), and desired power is supplied to the power output unit OUT.

  When the SOC of the main battery module 100 is less than the expected SOC value, power corresponding to the difference between the SOC and the expected SOC value is supplied to the main battery module 100 from at least one of the power input unit IN and the auxiliary battery module 200. The Further, the power of the main battery module 100 is not supplied to the power output unit OUT, and at least one of the power input unit IN and the auxiliary battery module 200 is supplied to the power output unit OUT as necessary. Thereby, the SOC of the main battery module 100 follows the change of the SOC expected value (SOC expected value function), and desired power is supplied to the power output unit OUT.

  In the second control example, the SOC expected value function is set so that the SOC expected value changes between a predetermined value (for example, 15% to 85%) and a sudden change is suppressed. Therefore, the main battery module 100 is not maintained for a long time in a state of high SOC of 85% or more. Thereby, the calendar life of the main battery module 100 is prolonged. Further, in the second control example, the SOC of the main battery module 100 is limited to between 15% and 85%, and the charge / discharge frequency of the main battery module 100 is reduced. Thereby, the cycle life of the main battery module 100 is prolonged. As a result, the life of the main battery module 100 can be extended.

  In addition, as in the X part of FIG. 8, it may be necessary to supply power to the power output unit OUT when the SOC of the main battery module 100 is reduced to 15%. In this case, as shown by a dotted line in FIG. 8, the SOC of the auxiliary battery module 200 is maintained in a high state. Therefore, power can be supplied from the auxiliary battery module 200 to the power output unit OUT. Thus, when the SOC of the main battery module 100 decreases, the SOC of the auxiliary battery module 200 increases. Therefore, even when the SOC of the main battery module 100 is reduced to 15%, the battery system 500 can supply power to the load.

(6) Third Control Example of SOC of Main Battery Module FIG. 9 is a diagram illustrating a result of SOC simulation of the main battery module 100 and the auxiliary battery module 200 in the third control example.

  In the third control example, it is assumed that the SOC of the main battery module 100 is accurately estimated. The SOC expected value function is set so that the SOC expected value temporarily decreases to 0%, as indicated by a two-dot chain line in FIG. The SOC of main battery module 100 can be estimated by a known method for estimating SOC or an algorithm for estimating SOC based on the open circuit voltage of battery cell 10 or the current flowing through main battery module 100. In this embodiment, the SOC is calculated based on the following formula (1). That is, the SOC is obtained by dividing the difference between the accumulated current amount due to charging and the accumulated current amount due to discharging by the full charge current capacity.

SOC = (charge current integrated amount [Ah] −discharge current integrated amount [Ah])
/ Full charge current capacity [Ah] × 100 [%] (1)
The SOC calculated by Equation (1) has an error. Therefore, it is necessary to periodically reset the calculated current integration amount. The accumulated current amount is reset by discharging the main battery module 100 until the SOC becomes 0%. From this state, the SOC can be accurately calculated by calculating the expression (1) in the subsequent charge / discharge.

  Further, as the main battery module 100 deteriorates, the full charge current capacity of the denominator of the formula (1) changes with time. Therefore, it is necessary to periodically update the full charge current capacity. The full charge current capacity is updated by discharging the main battery module 100 until the SOC changes from 100% to 0%. The discharge current integrated amount supplied from the main battery module 100 by this discharge becomes the full charge current capacity.

  When the SOC of the main battery module 100 is not controlled, the main battery module 100 is maintained in a charged state until the SOC becomes 80% or more, as shown by a one-dot chain line in FIG. Therefore, it is impossible to reset the accumulated current amount of the main battery module 100. Further, the full charge current capacity of the main battery module 100 cannot be updated.

  Thus, depending on the load connected to the power output unit OUT, the main battery module 100 cannot be discharged until the SOC becomes 0%. Even if the main battery module 100 can be discharged until the SOC becomes 0%, the power supplied for discharging is wasted if the load is not used. Further, when the discharge of the main battery module 100 is rapid until the SOC changes from 100% to 0%, the cycle life of the main battery module 100 is shortened.

  Further, as in the second control example, when the SOC of the main battery module 100 is not controlled, the main battery module 100 deteriorates by maintaining a high SOC state (for example, 80% or more). Thereby, the calendar life of the main battery module 100 is shortened.

  On the other hand, when the SOC of the main battery module 100 is controlled, as shown by a solid line in FIG. 9, the charge / discharge of the main battery module 100 is performed so that the SOC follows a change in the SOC expected value (SOC expected value function). Done. The charge / discharge control among the main battery module 100, the auxiliary battery module 200, the power input unit IN, and the power output unit OUT in the third control example is the same as in the first control example and the second control example.

  In the third control example, the SOC expected value function is set so that the SOC expected value gradually decreases from 100% to 0% at a constant rate and then increases gradually at a constant rate. Therefore, the SOC of the main battery module 100 gradually decreases from 100% to 0% at a constant rate. Thereby, the electric current integration amount of the main battery module 100 can be reset. Further, the full charge current capacity of the main battery module 100 can be updated. Thereafter, the SOC of the main battery module 100 gradually increases at a constant rate. Since the SOC at this time is immediately after being reset, it is accurately calculated.

  In the third control example, charging / discharging of the main battery module 100 is performed such that the SOC of the main battery module 100 changes gradually, so that the cycle life of the main battery module 100 is prolonged. Further, since the main battery module 100 is not maintained for a long time in a high SOC state (for example, 80% or more), the calendar life of the main battery module 100 is prolonged. As a result, the life of the main battery module 100 can be extended.

  In the control example 3, the main battery module 100 is discharged until the SOC changes from 100% to 0% in order to reset the accumulated current amount and update the full charge current capacity. Electric power supplied for discharging can be stored in the auxiliary battery module 200. Therefore, even when a load connected to the power output unit OUT is not used, power supplied for discharging is not wasted.

  Furthermore, as shown in the Y part of FIG. 9, it may be necessary to supply power to the power output unit OUT when the SOC of the main battery module 100 decreases to 0%. In this case, as shown by a dotted line in FIG. 9, the SOC of the auxiliary battery module 200 is maintained in a high state. Therefore, power can be supplied from the auxiliary battery module 200 to the power output unit OUT. Thus, when the SOC of the main battery module 100 decreases, the SOC of the auxiliary battery module 200 increases. Therefore, even when the SOC of the main battery module 100 is reduced to 0%, the battery system 500 can supply power to the load.

  Battery ECU 300 can set the SOC expected value function by combining control example 1, control example 2, and control example 3 described above.

(7) Effect In battery system 500 according to the present embodiment, the frequency with which main battery module 100 is discharged is reduced until the SOC of main battery module 100 decreases from 100% to 0%. Similarly, the frequency with which the main battery module 100 is charged until the SOC of the main battery module 100 reaches 0% to 100% is reduced. Thereby, the deterioration of the main battery module 100 due to the cycle life is alleviated. Further, the main battery module 100 is prevented from being maintained for a long time in a high SOC state (for example, 80% or more). Thereby, the deterioration of the main battery module 100 due to the calendar life is alleviated. As a result, the life of the main battery module 100 can be extended.

  Further, when the SOC of the auxiliary battery module 200 does not reach 100% regardless of the load connected to the power output unit OUT, the main battery is maintained until the SOC of the main battery module 100 reaches 0% without wasting power. The module 100 can be discharged. Thereby, the electric current integration amount of the main battery module 100 can be reset. Thereafter, the main battery module 100 can be charged until the SOC of the main battery module 100 reaches 100%. Thereby, the full charge current capacity of the main battery module 100 can be updated more accurately.

  Furthermore, when the SOC of the main battery module 100 is low, the SOC of the auxiliary battery module 200 is controlled to be relatively high. Thereby, even when it becomes necessary to supply power to the power output unit OUT when the SOC of the main battery module 100 decreases, power can be supplied from the auxiliary battery module 200 to the power output unit OUT. On the other hand, when the SOC of the main battery module 100 is high, the SOC of the auxiliary battery module 200 is controlled to be relatively low. Therefore, when the main battery module 100 is discharged, the auxiliary battery module 200 can store the power supplied by the main battery module 100. As a result, even when power is not supplied to the power output unit OUT, the main battery module 100 can be discharged without wasting power.

  As described above, the SOC of the main battery module 100 changes to an optimum value regardless of whether a load is connected to the power output unit OUT, whether the load is used, and how the load is used. Can be made. In addition, values such as the SOC and the full charge current capacity of the main battery module 100 can be accurately measured. As a result, the user can prevent deterioration of the main battery module 100 even when the battery system 500 is connected to or removed from the load, power supply line, or charger at an arbitrary timing.

  As a result, the SOC of the main battery module 100 is maintained at an optimum value while saving the effort of optimizing the method for estimating the SOC, and the values of the SOC and the full charge current capacity of the main battery module 100 are measured more accurately. can do. In addition, the configuration of the algorithm (software) used for estimating the SOC of the main battery module 100 in the battery system 500 can be simplified. That is, the SOC history of the main battery module 100 can be shifted to an optimum state simply by changing the SOC expected value function. Thereby, the trouble of preparing a calculation program for the SOC value optimized for each power request pattern of the load connected to the power output unit OUT is saved. Moreover, the trouble of optimizing the program is saved. In the present embodiment, even when the SOC of the main battery module 100 is lowered, the auxiliary battery module 200 can supply power to the power output unit OUT. Thus, battery ECU 300 can perform control to increase or decrease the SOC value of main battery module 100 as desired. Furthermore, the battery system 500 can be commonly used for various loads.

[2] Second Embodiment Hereinafter, an electric vehicle and other moving bodies will be described as moving bodies according to a second embodiment. The moving body according to the present embodiment includes battery system 500 according to the first embodiment.

(1) Configuration and operation of electric vehicle An electric vehicle will be described as an example of the electric vehicle according to the second embodiment. FIG. 10 is a block diagram illustrating a configuration of an electric vehicle including the battery system 500. As shown in FIG. 10, the electric automobile 600 includes a vehicle body 610. The vehicle body 610 is provided with a battery system 500, a power conversion unit 601, a motor 602, drive wheels 603, an accelerator device 604, a brake device 605, a rotation speed sensor 606, and a main control unit 607. When motor 602 is an alternating current (AC) motor, power conversion unit 601 includes an inverter circuit.

  The battery system 500 is connected to the motor 602 via the power conversion unit 601 and is also connected to the main control unit 607. The main control unit 607 is given a charge amount of the main battery module 100 (see FIG. 1) from a battery ECU 300 (see FIG. 1) constituting the battery system 500. In addition, an accelerator device 604, a brake device 605, and a rotation speed sensor 606 are connected to the main control unit 607. The main control unit 607 is composed of, for example, a CPU and a memory, or a microcomputer.

  The accelerator device 604 includes an accelerator pedal 604a included in the electric automobile 600 and an accelerator detection unit 604b that detects an operation amount (depression amount) of the accelerator pedal 604a. When the accelerator pedal 604a is operated by the driver, the accelerator detector 604b detects the operation amount of the accelerator pedal 604a based on a state where the driver is not operated. The detected operation amount of the accelerator pedal 604a is given to the main control unit 607.

  The brake device 605 includes a brake pedal 605a included in the electric automobile 600 and a brake detection unit 605b that detects an operation amount (depression amount) of the brake pedal 605a by the driver. When the brake pedal 605a is operated by the driver, the operation amount is detected by the brake detection unit 605b. The detected operation amount of the brake pedal 605a is given to the main control unit 607.

  The rotation speed sensor 606 detects the rotation speed of the motor 602. The detected rotation speed is given to the main control unit 607.

  The main control unit 607 is given the charge amount of the main battery module 100, the value of the current flowing through the main battery module 100, the operation amount of the accelerator pedal 604a, the operation amount of the brake pedal 605a, and the rotation speed of the motor 602. The main control unit 607 performs charge / discharge control of the main battery module 100 and power conversion control of the power conversion unit 601 based on these pieces of information.

  For example, the electric power of the main battery module 100 is supplied from the battery system 500 to the power conversion unit 601 when the electric vehicle 600 is started and accelerated based on the accelerator operation.

  Further, the main control unit 607 calculates a rotational force (command torque) to be transmitted to the drive wheels 603 based on the given operation amount of the accelerator pedal 604a, and outputs a control signal based on the command torque to the power conversion unit 601. To give.

  The power conversion unit 601 that has received the control signal converts the power supplied from the battery system 500 into power (drive power) necessary for driving the drive wheels 603. As a result, the driving power converted by the power converter 601 is supplied to the motor 602, and the rotational force of the motor 602 based on the driving power is transmitted to the driving wheels 603.

  On the other hand, when the electric automobile 600 is decelerated based on the brake operation, the motor 602 functions as a power generator. In this case, the power conversion unit 601 converts the regenerative power generated by the motor 602 into power suitable for charging the main battery module 100 and supplies the converted power to the main battery module 100. Thereby, the main battery module 100 is charged.

(2) Effects in the Electric Vehicle Since the electric vehicle 600 uses the battery system 500 according to the first embodiment, the life of the main battery module 100 of the electric vehicle 600 can be extended. Therefore, it is possible to improve the reliability and reduce the cost of the electric automobile 600.

(3) Configuration and Operation of Other Mobile Body The battery system 500 may be mounted on another mobile body such as a ship, an aircraft, an elevator, or a walking robot.

  A ship equipped with the battery system 500 includes, for example, a hull instead of the vehicle body 610 in FIG. 10, a screw instead of the drive wheel 603, an acceleration input unit instead of the accelerator device 604, and a brake device 605. Instead, a deceleration input unit is provided. The driver operates the acceleration input unit instead of the accelerator device 604 when accelerating the hull, and operates the deceleration input unit instead of the brake device 605 when decelerating the hull. In this case, the hull corresponds to the moving main body, the motor corresponds to the power source, and the screw corresponds to the drive unit. The ship does not have to include a deceleration input unit. In this case, when the driver operates the acceleration input unit to stop the acceleration of the hull, the hull is decelerated due to the resistance of water. In such a configuration, the motor receives electric power from the battery system 500 and converts the electric power into power, and the hull moves by rotating the screw with the converted power.

  An aircraft equipped with the battery system 500 includes, for example, a fuselage instead of the vehicle body 610 in FIG. 10, a propeller instead of the driving wheel 603, an acceleration input unit instead of the accelerator device 604, and a brake device 605. Instead, a deceleration input unit is provided. Ships and aircraft do not have to include a deceleration input unit. In this case, when the driver operates the acceleration input unit to stop acceleration, the airframe is decelerated due to water resistance or air resistance.

  An elevator equipped with the battery system 500 includes, for example, a saddle instead of the vehicle body 610 in FIG. And a deceleration input unit instead of the brake device 605.

  The walking robot equipped with the battery system 500 includes, for example, a torso instead of the vehicle body 610 in FIG. 10, a foot instead of the driving wheel 603, an acceleration input unit instead of the accelerator device 604, and a brake device 605. A deceleration input unit is provided instead of.

  In these moving bodies, the motor corresponds to a power source, the hull, gas, dredging, and the trunk correspond to the main body, and the screw, propeller, lifting rope and foot correspond to the drive unit. The power source receives electric power from the battery system 500 and converts the electric power into motive power, and the drive unit moves the moving main body portion with the motive power converted by the motive power source.

(4) Effects in Other Moving Objects Since the battery system 500 according to the first embodiment is used also in such various moving objects, the life of the main battery module of the moving object can be prolonged. Therefore, it is possible to improve the reliability of the moving body and reduce the cost.

(5) Modified Example of Moving Body In the electric vehicle 600 of FIG. 10 or another moving body, the main control unit 607 may have the same function as the battery ECU 300 instead of the battery ECU 300 provided in each battery system 500. Good.

[3] Third Embodiment A power supply device according to a third embodiment will be described. The power supply device according to the present embodiment includes a battery system 500 according to the first embodiment.

(1) Configuration and Operation FIG. 11 is a block diagram illustrating a configuration of a power supply device including the battery system 500. As illustrated in FIG. 11, the power supply device 700 includes a power storage device 710 and a power conversion device 720. The power storage device 710 includes a battery system group 711 and a system controller 712. The battery system group 711 includes the battery system 500 according to the first embodiment. Between the plurality of battery systems 500, the plurality of battery cells 10 may be connected to each other in parallel, or may be connected to each other in series.

  The system controller 712 is an example of a system control unit, and includes, for example, a CPU and a memory, or a microcomputer. The system controller 712 is connected to the battery ECU 300 (see FIG. 1) of each battery system 500. The battery ECU 300 of each battery system 500 calculates the charge amount of each battery cell 10 based on the terminal voltage of each battery cell 10 (see FIG. 1), and gives the calculated charge amount to the system controller 712. The system controller 712 controls the power conversion device 720 based on the charge amount of each battery cell 10 given from each battery ECU 300, thereby controlling the discharge or charging of the plurality of battery cells 10 included in each battery system 500. I do.

  Power conversion device 720 includes a DC / DC (direct current / direct current) converter 721 and a DC / AC (direct current / alternating current) inverter 722. The DC / DC converter 721 has an input terminal 721a, an output terminal 721b, and an input / output terminal 721c, and the DC / AC inverter 722 has input / output terminals 722a and 722b. An input terminal 721 a and an output terminal 721 b of the DC / DC converter 721 are connected to the battery system group 711 of the power storage device 710. Similar to the arrow i in FIG. 1, the power output units OUT (see FIG. 1) of the plurality of battery systems 500 output power to the input terminal 721 a of the DC / DC converter 721. Similarly to the arrow h in FIG. 1, the power input units IN (see FIG. 1) of the plurality of battery systems 500 receive power from the output terminal 721 b of the DC / DC converter 721. The input terminal 721a and the input / output terminal 721b may be configured as one input / output terminal as a bidirectional power supply line.

  The input / output terminal 721c of the DC / DC converter 721 and the input / output terminal 722a of the DC / AC inverter 722 are connected to each other and to the power output unit PU1. The input / output terminal 722b of the DC / AC inverter 722 is connected to the power output unit PU2 and to another power system. The power output units PU1, PU2 include, for example, outlets. For example, various loads are connected to the power output units PU1 and PU2. Other power systems include, for example, commercial power sources or solar cells. This is an external example in which power output units PU1, PU2 and another power system are connected to a power supply device.

  The DC / DC converter 721 and the DC / AC inverter 722 are controlled by the system controller 712, whereby the plurality of battery cells 10 included in the battery system group 711 are discharged and charged.

  When the battery system group 711 is discharged, power supplied from the battery system group 711 is DC / DC (direct current / direct current) converted by the DC / DC converter 721, and further DC / AC (direct current / alternating current) conversion is performed by the DC / AC inverter 722. Is done.

  The power DC / DC converted by the DC / DC converter 721 is supplied to the power output unit PU1. The power DC / AC converted by the DC / AC inverter 722 is supplied to the power output unit PU2. DC power is output to the outside from the power output unit PU1, and AC power is output to the outside from the power output unit PU2. The electric power converted into alternating current by the DC / AC inverter 722 may be supplied to another electric power system.

  The system controller 712 performs the following control as an example of control related to the discharge of the plurality of battery cells 10 included in each battery system 500. When the battery system group 711 is discharged, the system controller 712 determines whether to stop discharging based on the charge amount of each battery cell 10 given from each battery ECU 300 (see FIG. 1), and based on the determination result. The power converter 720 is controlled. Specifically, when the charge amount of any one of the plurality of battery cells 10 (see FIG. 1) included in the battery system group 711 becomes smaller than a predetermined threshold, the system controller 712 The DC / DC converter 721 and the DC / AC inverter 722 are controlled so that the discharge is stopped or the discharge current (or discharge power) is limited. Thereby, overdischarge of each battery cell 10 is prevented.

  On the other hand, when the battery system group 711 is charged, AC power supplied from another power system is AC / DC (AC / DC) converted by the DC / AC inverter 722, and further DC / DC (DC) is converted by the DC / DC converter 721. / DC) converted. When power is supplied from the DC / DC converter 721 to the battery system group 711, the plurality of battery cells 10 (see FIG. 1) included in the battery system group 711 are charged.

  The system controller 712 performs the following control as an example of control related to charging of the plurality of battery cells 10 included in each battery system 500. When charging the battery system group 711, the system controller 712 determines whether or not to stop charging based on the charge amount of each battery cell 10 given from each battery ECU 300 (see FIG. 1), and based on the determination result. The power converter 720 is controlled. Specifically, when the charge amount of any one of the plurality of battery cells 10 included in the battery system group 711 exceeds a predetermined threshold value, the system controller 712 stops charging. Or the DC / DC converter 721 and the DC / AC inverter 722 are controlled such that the charging current (or charging power) is limited. Thereby, overcharge of each battery cell 10 is prevented.

(2) Effect As described above, since the power supply apparatus 700 according to the present embodiment is provided with the battery system 500 according to the first embodiment, the life of the main battery module 100 of the power supply apparatus 700 is extended. can do. Therefore, the reliability of the power supply device 700 can be improved and the cost can be reduced.

(3) Modified Example of Power Supply Device In the power supply device 700 of FIG. 11, the system controller 712 may have the same function as the battery ECU 300 instead of providing the battery ECU 300 in each battery system 500.

  The power conversion device 720 may have only one of the DC / DC converter 721 and the DC / AC inverter 722 as long as power can be supplied between the power supply device 700 and the outside. Further, the power conversion device 720 may not be provided as long as power can be supplied between the power supply device 700 and the outside.

  In the power supply device 700 of FIG. 11, a plurality of battery systems 500 are provided, but not limited to this, only one battery system 500 may be provided.

  When the power supply apparatus 700 includes a plurality of battery systems 500, at least one battery system 500 may operate as the main battery module 100, and another battery system 500 may operate as the auxiliary battery module 200. In this case, the system controller 712 performs control related to charging / discharging of each battery system 500.

[4] Other Embodiments (1) In the first embodiment, the positions where the main battery module 100 and the auxiliary battery module 200 are installed are not limited, and the main battery module 100 and the auxiliary battery module 200 are separated from each other. May be installed. For example, the main battery module 100 may be mounted on an electric vehicle as a power source for the electric vehicle, and the auxiliary battery module 200 may be installed in a house as a household power source for saving. Further, the main battery module 100 may be installed in the first house as a household saving power source, and the auxiliary battery module 200 may be installed in the second house as a household saving power source.

  Furthermore, when the main battery module 100 and the auxiliary battery module 200 have the same configuration, the roles of the main battery module 100 and the auxiliary battery module 200 may be exchanged every time. That is, depending on the situation, the main battery module 100 may be the auxiliary battery module 200, and the auxiliary battery module 200 may be the main battery module 100.

  (2) In the first embodiment, the battery system 500 includes one main battery module 100, but is not limited thereto. The battery system 500 may include a plurality of main battery modules. Similarly, the battery system 500 includes one auxiliary battery module 200, but is not limited thereto. The battery system 500 may include a plurality of auxiliary battery modules 200.

  For example, the battery system 500 may include four main battery modules 100 and one auxiliary battery module 200. Similarly, one main battery module 100 in which the battery system 500 is installed in the first house, and four auxiliary battery modules 200 installed in the second, third, fourth, and fifth houses, respectively. May be included.

  (3) Although SOC is used as the state of charge in the first embodiment, the present invention is not limited to this. As the state of charge, an open circuit voltage, a remaining capacity, a depth of discharge, an integrated current value, or a stored charge amount may be used instead of the SOC.

  (4) In the first embodiment, the SOC expected value function is not limited to the SOC expected value function set in the first to third control examples, and can be arbitrarily set.

[5] Correspondence relationship between each constituent element of claim and each part of the embodiment Hereinafter, an example of correspondence between each constituent element of the claim and each part of the embodiment will be described. It is not limited.

  The battery cell 10 is an example of a battery cell, the main battery module 100 is an example of a main battery module, and the auxiliary battery module 200 is an example of an auxiliary battery module. SOC, open-circuit voltage, remaining capacity, depth of discharge, accumulated current value or difference in charged amount are examples of the charged state, and the expected SOC function is an example of the target function. The power input unit IN is an external example, and a mobile phone, a personal computer, or a motor of an electric vehicle is an example of an external load. The battery ECU 300 is an example of a control device, the memory 320 is an example of a storage unit, the CPU 310 is an example of a power supply control unit, and the battery system 500 is an example of a battery system.

  The motor 602 is an example of a motor and an external device, the driving wheel 603 is an example of a driving wheel, and the electric automobile 600 is an example of an electric vehicle. A body 610, a ship hull, an aircraft fuselage, an elevator cage, or a torso of a walking robot are examples of the moving main body. A foot is an example of a power source. An electric vehicle 600, a ship, an aircraft, an elevator, or a walking robot are examples of moving objects. The system controller 712 is an example of a system control unit, the power storage device 710 is an example of a power storage device, the power supply device 700 is an example of a power supply device, and the power conversion device 720 is an example of a power conversion device.

  As each constituent element in the claims, various other elements having configurations or functions described in the claims can be used.

DESCRIPTION OF SYMBOLS 10 Battery cell 100 Main battery module 200 Auxiliary battery module 300 Battery ECU
310 CPU
320 Memory 500 Battery system 600 Electric vehicle 601 Power conversion unit 602 Motor 603 Drive wheel 604 Accelerator device 604a Accelerator pedal 604b Accelerator detector 605 Brake device 605a Brake pedal 605b Brake detector 606 Rotational speed sensor 607 Main controller 700 Power supply 700 710 Power storage device 711 Battery system group 712 System controller 720 Power conversion device 721 DC / DC converter 721a Input terminal 721b Output terminal 721c, 722a, 722b Input / output terminal 722 DC / AC inverter ai arrow BS bus IN Power input unit OUT Power output unit PU1, PU2 Power output unit

Claims (10)

A main battery module including a battery cell;
An auxiliary battery module connected to the main battery module;
Control charging of at least one of the main battery module and the auxiliary battery module with electric power supplied from the outside so that the charging state of the main battery module follows a target function that changes in a preset time axis direction. A control device for controlling supply of electric power to an external load by discharging at least one of the main battery module and the auxiliary battery module, and controlling charging and discharging between the main battery module and the auxiliary battery module A battery system comprising: The control device includes at least one of a comparison result between the target function and the state of charge of the main battery module, power supplied from the outside, power requested from an external load, and power stored in the auxiliary battery module. The battery system according to claim 1, wherein charging and discharging of the main battery module and the auxiliary battery module are controlled on the basis of the voltage. The control device selectively performs charging of the main battery module by discharging of the auxiliary battery module and charging of the auxiliary battery module by discharging of the main battery module based on the target function. 2. The battery system according to 2. The controller is
When the state of charge of the main battery module is smaller than the value of the target function, externally so that the main battery module is charged by at least one of electric power supplied from the outside and electric power supplied from the auxiliary battery module And controlling power supply from the auxiliary battery module,
When the state of charge of the main battery module is larger than the value of the target function, an external load and an external load so that the main battery module is discharged by power supply to at least one of an external load and the auxiliary battery module The battery system as described in any one of Claims 1-3 which controls supply of the electric power to the said auxiliary battery module. The controller is
When the power supplied from the outside is larger than the power required from the external load and the state of charge of the main battery module is larger than the value of the target function, the power supplied from the outside and the main battery module The supply of power from the outside and the main battery module is controlled so that the auxiliary battery module is charged by at least one of the supplied power, and the power supplied from the outside is more than the power required from the external load. The auxiliary battery module is discharged by supplying power to at least one of an external load and the main battery module when the charge is small or when the state of charge of the main battery module is smaller than the value of the target function. Controlling supply of electric power to an external load and the main battery module according to any one of claims 1 to 4. Placing the battery system. Connected to a main battery module including battery cells and an auxiliary battery module connected to the main battery module;
A storage unit for storing a target function of the state of charge of the main battery module set in advance to change in the time axis direction;
Controlling charging of at least one of the main battery module and the auxiliary battery module by electric power supplied from the outside so that a charging state of the main battery module follows the preset target function, and the main battery module And a power supply control unit that controls supply of electric power to an external load due to discharge of at least one of the auxiliary battery modules, and controls charging and discharging between the main battery module and the auxiliary battery module. apparatus. The battery system according to any one of claims 1 to 5,
A motor driven by power from the main battery module of the battery system;
An electric vehicle comprising drive wheels that are rotated by the rotational force of the motor. The battery system according to any one of claims 1 to 5,
A moving body,
A power source for converting electric power from the main battery module of the battery system into power for moving the moving main body,
A moving body comprising: a drive unit that moves the moving main body unit by power converted by the power source. The battery system according to any one of claims 1 to 5,
A power storage device comprising: a system control unit that performs control related to charging or discharging of the main battery module of the battery system. Can be connected to the outside,
The power storage device according to claim 9,
A power supply device comprising: a power conversion device that is controlled by the system control unit of the power storage device and performs power conversion between the main battery module of the battery system of the power storage device and the outside.

Images