State of charge management method, state of charge management device, and state of charge management system

Abstract

This charge state management method: sets a provisional target state of charge for a power battery (53) of an electric vehicle (50) for when the power battery (53) is to be charged; and determines an ultimate target state of charge for the power battery (53) on the basis of the provisional target state of charge. The provisional target state of charge set for upcoming charging of the power battery (53) is corrected on the basis of a history (Δ1) of when the provisional target state of charge was modified due to a request by a user of the electric vehicle (50), and a history (Δ2) of a change in the state of charge after charging of the power battery (53) that was charged to the ultimate target state of charge.

Description

CHARGE STATE MANAGEMENT METHOD, CHARGE STATE MANAGEMENT DEVICE, AND CHARGE STATE MANAGEMENT SYSTEM

[0001] The present invention relates to a charge state management method, a charge state management device, and a charge state management system.

[0002] Patent Literature 1 describes a capacity control device that manages the capacity of a battery, which is a driving power source for a vehicle, by dividing it into a capacity that can be used for transmitting and receiving power between the battery and a power grid without relying on instructions from the vehicle user, and a capacity that can be used by the user based on instructions from the user. This device charges and discharges the battery intended for use by the user within the range of the capacity that can be used by the user, without touching the capacity that can be used for transmitting and receiving power to and from the power grid.

[0003] Japanese Patent Application Laid-Open No. 2022-110032

[0004] In the technology of Patent Document 1, the capacity of the battery managed for each purpose of use is fixed. Battery charging control performed within the range of the fixed capacity cannot flexibly respond to situations where, for example, the amount of power required for the battery during vehicle operation changes due to circumstances on the vehicle side.

[0005] The present invention has been made in view of the above circumstances, and an object of the present invention is to be able to flexibly respond to situations in which the amount of electric power required for the power battery changes while the electric vehicle is in operation.

[0006] In order to solve the above-mentioned problems, a state of charge management method according to one aspect of the present invention sets a temporary target state of charge for the power battery of an electric vehicle when charging the power battery, and determines a final target state of charge for the power battery based on the temporary target state of charge. The temporary target state of charge to be set the next time the power battery is charged is corrected based on a history of changes to the temporary target state of charge at the request of the user of the electric vehicle and a history of changes in the state of charge after charging the power battery that was charged to the final target state of charge.

[0007] According to the present invention, it is possible to flexibly respond to situations in which the required amount of charging power for the power battery of an electric vehicle changes.

[0008] Fig. 1 is a diagram showing an example of the overall configuration of a power management system to which a state-of-charge management method according to an embodiment of the present invention is applied. Fig. 2 is a flowchart outlining an example of a procedure for determining a target state of charge for a power battery. Fig. 3 is a diagram showing an example of the relationship between a change in the state of charge of a power battery set to a final target state of charge during operation of an electric vehicle and a tentative target state of charge set by a power supply and demand management device before the next charging after operation ends. Fig. 4 is a flowchart showing an example of the procedure for the state-of-charge management method according to an embodiment of the present invention. Fig. 5 is a flowchart showing an example of the procedure for the state-of-charge management method according to an embodiment of the present invention.

[0009] Hereinafter, an embodiment of the present invention and its modifications will be described with reference to the drawings. In the description of the drawings, the same parts are given the same reference numerals and the description thereof will be omitted.

[0010] An example of the overall configuration of a power management system to which a state-of-charge management method according to an embodiment of the present invention is applied will be described with reference to Fig. 1. The power management system is a system that manages the supply and demand of power in an entire power supply and demand system. As shown in Fig. 1, the power management system includes a power supply and demand system 1, a power system monitoring and control system 2, and a power system 3.

[0011] The electricity supply and demand system 1 is a system that manages, for example, charges related to electricity for a facility, a single consumer location, etc. The system may be a system in which multiple consumer locations are virtually connected, rather than a single consumer location. The facility may be, for example, a building, a factory, a community, or a residence. In the following embodiment, an example of a building will be described. The electricity supply and demand system 1 includes a power meter 10, an electricity supply and demand management device 20, a user interface device 30, an electric vehicle charging and discharging facility 40, a non-controllable load 60, a controllable load 70, and a storage battery unit 90. An electric vehicle 50 is connected to the electric vehicle charging and discharging facility 40. The user interface device 30 is operated by a user of the electric vehicle 50 connected to the electric vehicle charging and discharging facility 40. Hereinafter, the user interface may be abbreviated as "UI." The charge state management method according to the embodiment can be applied when the electricity supply and demand management device 20 manages the charge state of a power battery 53 (described later) of the electric vehicle 50.

[0012] 1 illustrates one UI device 30, one electric vehicle charging / discharging facility 40, one uncontrollable load 60, one controllable load 70, and one storage battery unit 90. The power supply and demand system 1 may include two or more UI devices 30, two or more electric vehicle charging / discharging facilities 40, two or more uncontrollable loads 60, two or more controllable loads 70, and two or more storage battery units 90. The power supply and demand system 1 does not necessarily have to include the two or more uncontrollable loads 60, two or more controllable loads 70, and two or more storage battery units 90.

[0013] The power grid 3 is a power system that integrates power generation, power transformation, power transmission, and power distribution for supplying AC power from a power company to a group of power consumption elements in the power supply and demand system 1. In FIG. 1 , a driving battery 53 (described later) of an electric vehicle 50 connected to the electric vehicle charging and discharging equipment 40, a non-controllable load 60, a controllable load 70, and a storage battery 93 (described later) of the storage battery unit 90 correspond to the power consumption elements. Among the power consumption elements, the driving battery 53 and the storage battery 93 in particular perform both charging and discharging. The power grid 3 is connected to each of the electric vehicle charging and discharging equipment 40, the non-controllable load 60, the controllable load 70, and the storage battery unit 90 via a power meter 10.

[0014] The power system monitoring and control system 2 manages a target amount of power consumption in the power system 3. The target amount of power may be, for example, an annual peak power target value based on peaks in past power supply and demand plans.

[0015] The power meter 10 measures the power consumption by the power consumption elements of the power supply and demand system 1. The power meter 10 also measures the power supplied from the power supply and demand system 1 to the power grid 3.

[0016] The UI device 30 is a device used as a user interface by a user of the electric vehicle 50. The UI device 30 may be, for example, a portable terminal that the user of the electric vehicle 50 carries and uses on a daily basis, or may be provided inside the electric vehicle 50. The UI device 30 provided inside the electric vehicle 50 includes, for example, a general-purpose microcontroller and an input / output device, although these are not shown. The input / output device may be, for example, a display with a touch panel.

[0017] When the UI device 30 is a mobile terminal, the mobile terminal includes, for example, a smartphone or a tablet. The UI device 30 as a mobile terminal can, for example, launch application software (hereinafter referred to as an app) and input information on the app. The app may be a native app installed on the mobile terminal or a web app used by accessing a cloud server on the Internet on a web browser. In the following embodiment, for example, a smartphone on which a native app is installed is used as the UI device 30. By launching the app, a reception unit 301 (described later) can be virtually constructed in the UI device 30.

[0018] The electric vehicle charging / discharging equipment 40 is equipment to which an electric vehicle 50 is connected and which charges / discharges the power battery 53 of the electric vehicle 50. The electric vehicle charging / discharging equipment 40 may be located, for example, in a parking lot (not shown) of a building managed by the power supply and demand system 1. An electric vehicle 50 parked in the parking lot can be connected to the electric vehicle charging / discharging equipment 40 located in the parking lot. The electric vehicle charging / discharging equipment 40 is connected to the electric vehicle 50 via, for example, a power connector and charges the power battery 53 with power supplied from the power grid 3. The electric vehicle charging / discharging equipment 40 may also discharge stored power from the power battery 53 and supply the discharged power to the power grid 3 (this is called reverse power flow). Note that the connection method between the electric vehicle charging / discharging equipment 40 and the electric vehicle 50 and the charging / discharging method are not particularly limited. In the following description, two or more electric vehicles 50 connected to two or more electric vehicle charging / discharging equipment 40 of the power supply and demand system 1 may be referred to as an electric vehicle group.

[0019] The uncontrollable load 60 is a device or facility, such as a hair dryer, whose power demand (power consumption) cannot be controlled by an external command. On the other hand, the controllable load 70 is a facility, such as an air conditioning facility or a lighting facility, whose power demand (power consumption) can be controlled by an external command. The uncontrollable load 60 and the controllable load 70 are connected to the power grid 3 via a power meter 10. The controllable load 70 receives power from the power grid 3 in accordance with commands from a power supply and demand management device 20, which will be described later.

[0020] The storage battery unit 90 is installed, for example, in a building managed by the power supply and demand system 1. The storage battery unit 90 includes a charge / discharge control device 91, a charge / discharge device 92, and a storage battery 93. The charge / discharge control device 91 controls the charging and discharging of the storage battery 93. The charge / discharge control device 91 receives a command value for a target state of charge (SOC) of the storage battery 93 from the power supply and demand management device 20, which will be described later. The charge / discharge control device 91 controls the charging and discharging of the storage battery 93 so that the state of charge (SOC) of the storage battery 93 becomes the target state of charge of the command value received from the power supply and demand management device 20. The charge / discharge control device 91 charges the storage battery 93 when the command value is higher than the current SOC of the storage battery 93, and discharges the storage battery 93 when the command value is lower than the current SOC of the storage battery 93. The charge / discharge device 92 is an on-board charger (OBC) that charges and discharges the storage battery 93 under the control of the charge / discharge control device 91. The charging / discharging device 92 charges the storage battery 93 with power supplied from the power grid 3. The charging / discharging device 92 may also discharge the stored power from the storage battery 93 and supply the discharged power to the power grid 3 by reverse power flow.

[0021] The connection between the charge / discharge control device 91 and the power supply and demand management device 20 may be wired or wireless, or may be via the Internet, for example. When the power supply and demand system 1 has two or more storage battery units 90, the charge / discharge control device 91 of each storage battery unit 90 controls the charge and discharge of the storage batteries 93 of each storage battery unit 90 independently and in parallel. In the following description, the storage batteries 93 of the two or more storage battery units 90 included in the power supply and demand system 1 may be referred to as a storage battery group.

[0022] The electric vehicle 50 has a charge / discharge control device 51, a charge / discharge device 52, and a power battery 53. The charge / discharge control device 51 controls the charging and discharging of the power battery 53. The charge / discharge control device 51 receives a target state-of-charge command value (described later) for the power battery 53 from the power supply and demand management device 20. The charge / discharge control device 51 controls the charging and discharging of the power battery 53 so that the state of charge of the power battery 53 becomes the target state of charge of the command value received from the power supply and demand management device 20. The charge / discharge control device 51 charges the power battery 53 when the command value is higher than the current state of charge of the power battery 53, and discharges the power battery 53 when the command value is lower than the current state of charge of the power battery 53. The charge / discharge device 52 is an on-board charger (OBC) that charges and discharges the power battery 53 under the control of the charge / discharge control device 51. The charge / discharge device 52 charges the power battery 53 with power supplied from the power grid 3 via the electric vehicle charging / discharging equipment 40. Furthermore, the charging / discharging device 52 may discharge the stored power from the power battery 53 and supply the discharged power to the power grid 3 via the electric vehicle charging / discharging equipment 40 by reverse power flow.

[0023] The connection between the charge / discharge control device 51 and the power supply and demand management device 20 may be, for example, a wired connection via the connected electric vehicle charging / discharging facility 40, or a wireless connection using direct wireless communication between the charge / discharge control device 51 and the power supply and demand management device 20. The connection between the charge / discharge control device 51 and the power supply and demand management device 20 may be, for example, a connection via the Internet. When electric vehicles 50 are connected to two or more electric vehicle charging / discharging facilities 40 in the power supply and demand system 1, the charge / discharge control devices 51 of each electric vehicle 50 connected to each electric vehicle charging / discharging facility 40 control the charging and discharging of the power batteries 53 of each electric vehicle 50 independently and in parallel with each other.

[0024] The charge / discharge control devices 51, 91 of the electric vehicle 50 and the storage battery unit 90 each have a general-purpose microcontroller (not shown). The microcontroller includes a central processing unit (CPU) (not shown) having an input / output unit and a calculation unit, and a memory. The memory includes a read-only memory (ROM) and a random access memory (RAM). The microcontroller can virtually configure multiple information processing circuits by, for example, having the CPU execute a program stored in the memory. The multiple information processing circuits of the charge / discharge control devices 51, 91 can be used by the charge / discharge control devices 51, 91 to realize charge / discharge control of the power battery 53 and the storage battery 93 based on command values. The information processing circuit of the charge / discharge control device 51 can constitute a detection unit 511. The detection unit 511 can detect the charge state of the power battery 53 and changes in the charge state. The charge / discharge control device 51 having the detection unit 511 functions as a status monitoring device that monitors the charge state of the power battery 53.

[0025] In this embodiment, an example is shown in which multiple information processing circuits that implement the charge / discharge control of the power battery 53 and the storage battery 93 and the detection unit 511 of the charge / discharge control device 51 are implemented by software. Of course, it is also possible to configure the information processing circuits by providing dedicated hardware for executing the charge / discharge control of the power battery 53 and the storage battery 93 and the processing of the detection unit 511. Alternatively, the multiple information processing circuits may be configured by individual hardware. The dedicated hardware includes devices such as an application specific integrated circuit (ASIC) or conventional circuit components arranged to execute the charge / discharge control of the power battery 53 and the storage battery 93 and the processing of the detection unit 511.

[0026] The power supply and demand management device 20 has a function (power supply and demand management function) of managing the power supply and demand of the entire power supply and demand system 1, which includes the electric vehicles 50 connected to the electric vehicle charging and discharging equipment 40, the non-controllable loads 60, the controllable loads 70, the storage battery units 90, etc. The power supply and demand management device 20 predicts a power supply and demand plan that indicates trends in the power supply and demand of the power consumption elements excluding the electric vehicles and the storage batteries from the entire power supply and demand system 1. The power supply and demand management device 20, for example, stores past information on the power consumption of the power consumption elements excluding the electric vehicles and the storage batteries from the entire power supply and demand system 1. The power supply and demand management device 20 predicts the power demand of the building using, for example, the current power consumption of the power consumption elements excluding the electric vehicles and the storage batteries from the entire power supply and demand system 1, calculated from measurements by the power meter 10, etc., and the stored past power consumption. The power supply and demand management device 20 may predict the power demand of the building by taking into consideration, for example, calendar information including the day of the week and weather forecast information obtained from a weather forecast system (not shown). The power supply and demand management device 20 may also obtain, for example, an annual peak power target value of the power system 3 from the power system monitoring and control system 2, and predict the power demand of the building based on this.

[0027] The power supply and demand management device 20 has a function (electric vehicle group power management function) of managing the power charged and discharged to the power batteries 53 of the electric vehicles 50 connected to one or more electric vehicle charging / discharging facilities 40. The power supply and demand management device 20 also has a function (storage battery group power management function) of managing the power charged and discharged to the storage batteries 93 of one or more storage battery units 90. The power supply and demand management device 20 calculates target state-of-charge command values ​​for the power batteries 53 and the storage batteries 93 of the electric vehicles 50 connected to each electric vehicle charging / discharging facility 40. The power supply and demand management device 20 can determine the command values ​​based on the difference in power obtained by subtracting the actual power amount of power consumed by the power consumption elements of the entire group from the target power amount of power consumed by the power consumption elements of the entire group in the power supply and demand system 1. The power supply and demand management device 20 calculates the target power amount from the demand power predicted as a power supply and demand plan. The power supply and demand management device 20 calculates a difference in power amount by subtracting the actual power amount, which is the cumulative value of the power consumption of the power consumption elements measured by the power meter 10, from the target power amount. The power supply and demand management device 20 checks the state of charge of the power batteries 53 of the electric vehicles 50 connected to each electric vehicle charging / discharging equipment 40 and each storage battery 93 using the power management function of the electric vehicle group and the storage battery group. The power supply and demand management device 20 can calculate a command value for each power battery 53 and each storage battery 93 based on the checked state of charge and the above-mentioned difference in power amount. The power supply and demand management device 20 transmits, for example, a command value for the corresponding power battery 53 or storage battery 93 to the electric vehicles 50 and storage battery units 90 connected to each electric vehicle charging / discharging equipment 40.

[0028] The power supply and demand management device 20 has a general-purpose microcontroller (not shown). The microcontroller includes a central processing unit (CPU) and a memory. The memory includes a read-only memory (ROM) and a random access memory (RAM). The microcontroller can virtually construct multiple information processing circuits by having the CPU execute a program stored in the memory.

[0029] The multiple information processing circuits of the power supply and demand management device 20 can be used by the power supply and demand management device 20 to realize a power supply and demand management function, an electric vehicle group power management function, and a storage battery group power management function. The multiple information processing circuits can constitute each of the units 201 to 206 described below of the power supply and demand management device 20. In this embodiment, an example is shown in which the multiple information processing circuits are realized by software. Of course, it is also possible to configure the information processing circuits by providing dedicated hardware for executing the information processing of each of the units 201 to 206 described below. Alternatively, the multiple information processing circuits may be configured by individual hardware. The dedicated hardware includes devices such as application specific integrated circuits (ASICs) and conventional circuit components arranged to perform the functions of each of the units 201 to 206.

[0030] In addition to the microcontroller, the power supply and demand management device 20 includes a data storage 210 connected to the microcontroller. The data storage 210 may be, for example, a solid state drive (SSD) or a hard disk drive (HDD).

[0031] For example, when electric vehicles 50 are connected to electric vehicle charging / discharging equipment 40, the power supply and demand management device 20 uses its electric vehicle group power management function to determine a target state of charge when charging the power battery 53 of each electric vehicle 50 connected to electric vehicle charging / discharging equipment 40. Hereinafter, the target state of charge when charging the power battery 53 will be referred to as the target state of charge. The power supply and demand management device 20 that determines the target state of charge of the power battery 53 functions as a state of charge management device for the power battery 53.

[0032] Fig. 2 is a flowchart showing an outline of an example of a procedure for determining a target state of charge of the power battery 53. The procedure in the example of Fig. 2 progresses chronologically from the left, in order, before charging the power battery 53, after charging, and before the next charge. The procedure in the example of Fig. 2 involves the electric vehicle 50, the power supply and demand management device 20, and the UI device 30. In Fig. 2, the procedure involving the electric vehicle 50 is shown in the upper part, the procedure involving the power supply and demand management device 20 is shown in the middle part, and the procedure involving the UI device 30 is shown in the lower part.

[0033] When determining the target state of charge, the power supply and demand management device 20 sets a tentative target state of charge for the power battery 53 before charging the power battery 53 (step S1). Hereinafter, the tentative target state of charge will be referred to as the tentative target state of charge. The tentative target state of charge may be, for example, a predetermined value, or may be a value determined on an ad hoc basis taking into account the current state of charge of the power battery 53 or the differential power amount in the power supply and demand system 1 at the time the tentative target state of charge is set. The power supply and demand management device 20 notifies the UI device 30 of the set tentative target state of charge, and inquires of the user of the electric vehicle 50 via the UI device 30 whether or not there is a request to change the tentative target state of charge.

[0034] The user checks the tentative target state of charge set by the power supply and demand management device 20 on the UI device 30 and inputs a response to the inquiry into the UI device 30. When the user requests a change to the tentative target state of charge, the user inputs the change to the tentative target state of charge as a response to the UI device 30. The change to the tentative target state of charge may be, for example, the value of the tentative target state of charge after the change requested by the user, or the value of the difference Δ1 between the notified tentative target state of charge and the changed tentative target state of charge. The following description will be given of a case where the user inputs the difference Δ1 as the change. When requesting an increase in the tentative target state of charge, the user inputs a positive (+) value as the difference Δ1. When requesting a decrease in the tentative target state of charge, the user inputs a negative (-) value as the difference Δ1.

[0035] The UI device 30 accepts a response to the request to change the temporary target state of charge input by the user (step S3). The UI device 30 notifies the power supply and demand management device 20 of the user's response, including the difference Δ1, as a history of user requests to change the temporary target state of charge. The power supply and demand management device 20 stores the notified user's response in the data storage 210 of the power supply and demand management device 20. A database of the history of requests to change the temporary target state of charge is constructed in the data storage 210.

[0036] If the notified user's response includes the difference Δ1, the power supply and demand management device 20 changes the tentative target state of charge to a value obtained by adding the difference Δ1. After changing the tentative target state of charge if requested by the user, the power supply and demand management device 20 determines a final target state of charge, which will be the target state of charge when charging the power battery 53, based on the tentative target state of charge (step S5). Hereinafter, the final target state of charge will be referred to as the final target state of charge. Hereinafter, the tentative target state of charge and the final target state of charge will also be referred to as the tentative target SOC and the final target SOC. The procedures of steps S1 and S3 establish a mechanism by which the user can change the tentative target SOC of the power battery 53 set by the power supply and demand management device 20. With this mechanism, the power supply and demand management device 20 determines a final target SOC that reflects the change in the tentative target SOC made by the user. If the final target SOC is higher than the current state of charge, the power battery 53 is charged by charge / discharge control using the final target SOC as a command value. If the final target SOC is lower than the current state of charge, the power battery 53 is discharged by charge / discharge control using the final target SOC as a command value.

[0037] After charging and discharging the power battery 53, the electric vehicle 50 is disconnected from the electric vehicle charging and discharging equipment 40 and is in operation. While the electric vehicle 50 is in operation, for example, the state of charge of the power battery 53 decreases from the final target SOC due to power consumption caused by the running of the electric vehicle 50. Changes in the state of charge of the power battery 53 that occur during operation of the electric vehicle 50, including decreases in the state of charge due to power consumption of the power battery 53, are not reflected in the final target SOC determined by the power supply and demand management device 20 before charging the power battery 53.

[0038] 3 is a diagram showing an example of the relationship between a change in the state of charge of the power battery 53, which has been set as the final target SOC, during operation of the electric vehicle 50, and the tentative target SOC set by the power supply and demand management device 20 before the next charge after the operation ends. The graph in the upper left of FIG. 3 shows a case where, before charging the power battery 53, the user requests an increase in the tentative target SOC, and the power supply and demand management device 20 changes the tentative target SOC to a value obtained by adding a difference Δ1, the increase amount requested by the user, to the tentative target SOC. In this case, the final target SOC of the power battery 53 is determined to be the changed tentative target SOC, and then the power battery 53 is charged to the final target SOC.

[0039] After the power battery 53 is charged, the state of charge of the power battery 53 drops from the final target SOC due to power consumption by the electric vehicle 50 during operation. The graph shown on the left side at the bottom center of FIG. 3 shows an example of the state of charge of the power battery 53 before the next charge when the electric vehicle 50 after operation is connected to the electric vehicle charging / discharging equipment 40. The graph on the right side shows an example of the distribution of the state of charge of the power battery 53 at the start and end of past charging. It is considered that the state of charge of the power battery 53 at the start and end of past charging is distributed near the lower and upper limits, respectively, of the range of state of charge acceptable to the user for the power battery 53. In the example shown in the left graph, the state of charge of the power battery 53 before charging has decreased to a value close to the minimum value of the distribution range of the state of charge at the start of past charging of the power battery 53. If the state of charge of the power battery 53 further drops, the power battery 53 may approach the end-of-discharge voltage. If the state of charge of the power battery 53 drops to a similar value while the electric vehicle 50 is being operated after the next charge, it becomes necessary for the user to take measures such as additionally charging the power battery 53 at a facility (not shown) other than the electric vehicle charging / discharging equipment 40. In order to prevent the state of charge of the power battery 53 from dropping too much while the electric vehicle 50 is being operated, it is effective to reflect the details of the change in the state of charge of the power battery 53 that occurs while the electric vehicle 50 is being operated in the final target SOC of the power battery 53 that is determined at the time of the next charge.

[0040] As shown in FIG. 2 , during operation of the electric vehicle 50, the charge / discharge control device 51 records a deviation amount Δ2 as a history of changes in the state of charge of the power battery 53 after charging (step S7). The deviation amount Δ2 represents a history of the degree to which the state of charge detected by the detection unit 511 after charging the power battery 53 deviates from a predetermined range acceptable to the user. The deviation amount Δ2 can be, for example, the difference between the state of charge of the power battery 53 that is outside the user's acceptable range and the upper or lower limit of the acceptable range, whichever is closer to the state of charge. If the state of charge of the power battery 53 is within the user's acceptable range, the deviation amount Δ2 is set to 0. If the state of charge of the power battery 53 exceeds the upper limit of the acceptable range, the deviation amount Δ2 is set to a positive (+) value. If the state of charge of the power battery 53 falls below the lower limit of the acceptable range, the deviation amount Δ2 is set to a negative (-) value. The state of charge of the power battery 53 falls below the lower limit of the allowable range as the state of charge of the power battery 53 decreases. The deviation amount Δ2 when the state of charge of the power battery 53 falls below the lower limit of the allowable range is a parameter that includes the amount of decrease in the state of charge of the power battery after charging. For example, each time the detection unit 511 detects the state of charge of the power battery 53, the charge / discharge control device 51 can record the deviation amount Δ2 in association with a timestamp as a history of changes in the state of charge of the power battery 53 after charging.

[0041] The charge / discharge control device 51 can notify the recorded deviation amount Δ2 to a device outside the electric vehicle 50. The destination of the notification of the deviation amount Δ2 may be, for example, the power supply and demand management device 20 or a data management device 80 installed by a provider of a service provided to the electric vehicle 50. The data management device 80 may be installed outside the power supply and demand system 1. The service provided to the electric vehicle 50 may be, for example, a service utilizing the connected function of the electric vehicle 50. The power supply and demand management device 20 and the data management device 80, which are the destinations of the notification, store the notified deviation amount Δ2 in their own data storage. The deviation amount Δ2 may be stored separately for each operation of the electric vehicle 50. A database of a history of changes in the state of charge after charging the power battery 53 is constructed in the data storage. In this embodiment, a case will be described in which the charge / discharge control device 51 notifies the data management device 80 of the deviation amount Δ2. The connection between the charge / discharge control device 51 and the data management device 80 can be wireless, for example, via the Internet.

[0042] Before the next charge, the power supply and demand management device 20 sets a tentative target SOC based on correction amounts ΔSOC1 and ΔSOC2 corresponding to the difference Δ1 and the deviation amount Δ2, respectively (step S9). The tentative target SOC set by the power supply and demand management device 20 reflects the history of the user's request to change the tentative target SOC, including the difference Δ1, and the history of changes in the state of charge of the power battery 53 after charging, which is represented by the deviation amount Δ2. After setting the tentative target SOC based on the correction amounts ΔSOC1 and ΔSOC2, the procedures of steps S11 and S13, which are similar to steps S3 and S5 described above, continue. After the tentative target SOC of the power battery 53 is initially set and the final target SOC is initially determined through the procedures of steps S1 to S5, the procedures of steps S7 to S13 are repeated. Through the procedure of steps S7 to S13, before the next charge, the power supply and demand management device 20 sets a tentative target SOC that reflects the history of requests made by the user to change the tentative target SOC and the changes in the state of charge of the power battery 53 during operation of the electric vehicle 50. As shown in the graph in the upper right of Fig. 3 , the correction amounts ΔSOC1 and ΔSOC2 are reflected in the tentative target SOC set by the power supply and demand management device 20 before the next charge.

[0043] 1, the power supply and demand management device 20 includes a notification unit 201, a first acquisition unit 202, a change unit 203, a determination unit 204, a second acquisition unit 205, and a correction unit 206. These units 201 to 206, the reception unit 301 of the UI device 30, and the detection unit 511 of the charge / discharge control device 51 of the electric vehicle 50 can be used to realize the procedure illustrated in FIG.

[0044] The notification unit 201 notifies the user of the electric vehicle 50 equipped with the power battery 53 of the tentative target SOC of the power battery 53 set by the power supply and demand management device 20. The notification of the tentative target SOC to the user can be performed through the UI device 30. The UI device 30, for example, outputs the tentative target SOC notified by the power supply and demand management device 20 to notify the user, and inquires of the user whether or not there is a request to change the tentative target SOC. The UI device 30 can output the tentative target SOC, for example, by displaying it on a display.

[0045] The reception unit 301 of the UI device 30 receives the request to change the tentative target SOC notified to the user as a response to the inquiry. The reception unit 301 may be configured to receive the user's response by the user's operation on a touch panel, for example. When the user's response requests a change in the tentative target SOC, the response received by the reception unit 301 includes a difference Δ1 between the tentative target SOC and the tentative target SOC after the change. The UI device 30 can notify the power supply and demand management device 20 of the content of the user's response received by the reception unit 301.

[0046] The first acquisition unit 202 acquires the content of the user's request to change the tentative target SOC notified by the notification unit 201. When the content of the user's response notified by the UI device 30 requests a change of the tentative target SOC, the first acquisition unit 202 acquires the value of the difference Δ1 included in the content of the response.

[0047] When a user requests a change in the tentative target SOC, the change unit 203 changes the tentative target SOC of the power battery 53 in accordance with the content of the change request acquired by the first acquisition unit 202. For example, when the first acquisition unit 202 acquires the value of the difference Δ1, the change unit 203 changes the tentative target SOC set by the power supply and demand management device 20 to a value obtained by adding the difference Δ1. When the value obtained by adding the difference Δ1 exceeds 100%, the change unit 203 sets the changed tentative target SOC to 100%.

[0048] The determination unit 204 determines the final target SOC of the power battery 53 based on the tentative target SOC of the power battery 53. If the change unit 203 does not change the tentative target SOC, the determination unit 204 sets the tentative target SOC set by the power supply and demand management device 20 as the final target SOC of the power battery 53. If the change unit 203 changes the tentative target SOC, the determination unit 204 sets the tentative target SOC after change by the change unit 203 as the final target SOC of the power battery 53.

[0049] The second acquisition unit 205 acquires a history of changes in the state of charge after charging of the power battery 53 that has been charged to the final target SOC determined by the determination unit 204. "After charging" refers to after the electric vehicle 50 has been disconnected from the electric vehicle charging / discharging equipment 40, and the electric vehicle 50 is in operation after the power battery 53 has been charged. The second acquisition unit 205 acquires the deviation amount Δ2 during operation of the electric vehicle 50 as a history of changes in the state of charge after charging of the power battery 53. The second acquisition unit 205 can acquire, for example, from a notification destination to which the charge / discharge control device 51 has notified the deviation amount Δ2, the deviation amount Δ2 during operation of the electric vehicle 50 that has been accumulated in the data storage of the notification destination.

[0050] Before the next charging when the electric vehicle 50 that has finished operation is connected to the electric vehicle charging / discharging equipment 40 and the power battery 53 is charged, the correction unit 206 corrects the tentative target SOC set by the power supply and demand management device 20 before charging the power battery 53. The correction unit 206 corrects the tentative target SOC that will be set for the next charging, based on the change history of the tentative target SOC made by the change unit 203 before charging and the change history of the state of charge of the power battery 53 after charging, acquired by the second acquisition unit 205. The value of the tentative target SOC after correction shall not exceed 100%.

[0051] 4 and 5 are flowcharts showing an example of the procedure of a state-of-charge management method according to an embodiment of the present invention. This state-of-charge management method can be executed by a state-of-charge management system. The state-of-charge management system according to the embodiment can be configured to include a power supply and demand management device 20, a UI device 30, and a charge / discharge control device 51 for an electric vehicle 50.

[0052] As shown in FIG. 4 , when the electric vehicle 50 is connected to the electric vehicle charging / discharging facility 40, the power supply and demand management device 20 identifies the electric vehicle 50 and the user (step S101). A conventionally known method can be used to identify the electric vehicle 50 and the user. The power supply and demand management device 20 acquires information on the usage history of the identified electric vehicle 50 (step S103). For example, if the data management device 80 collects information about the electric vehicle 50 from the electric vehicle 50 using a connected function and the information includes the usage history of the electric vehicle 50, the power supply and demand management device 20 may acquire the usage history of the electric vehicle 50 from the data management device 80. The usage history of the electric vehicle 50 may include, for example, the mileage of the electric vehicle 50 for each date during operation. The connection between the power supply and demand management device 20 and the data management device 80 may be a wired connection, a wireless connection, or a connection via the Internet, for example.

[0053] The power supply and demand management device 20 acquires information on the charging history of the power battery 53 of the electric vehicle 50 by the identified user (step S105). The charging history of the power battery 53 by the user is a history of requests by the user to change the tentative target SOC set by the power supply and demand management device 20. In step S105, the first acquisition unit 202 of the power supply and demand management device 20 acquires the difference Δ1 in the history of changes to the tentative target SOC by the user from a database constructed in the data storage 210.

[0054] The power supply and demand management device 20 acquires information regarding the range acceptable to the user for the state of charge of the power battery 53 (step S107). This information is information for estimating a predetermined range acceptable to the user for the state of charge of the power battery 53 of the electric vehicle 50 connected to the electric vehicle charging / discharging equipment 40. The upper limit of the user's acceptable range for the state of charge of the power battery 53 can be estimated from the distribution of the state of charge at the end of previous charging of the power battery 53. The lower limit of the user's acceptable range for the state of charge of the power battery 53 can be estimated from the distribution of the state of charge at the start of previous charging of the power battery 53.

[0055] The distribution of the charge states of the power battery 53 at the start of past charging can be identified, for example, from the charge states detected by the detection unit 511 at the end of past operation when the electric vehicle 50 that has finished operation was connected to the electric vehicle charging / discharging equipment 40. For example, if the information about the electric vehicle 50 collected by the data management device 80 includes a history of the charge states of the power battery 53, this history information can be used to identify the distribution of the charge states of the power battery 53 at the start of past charging. The power supply and demand management device 20 may obtain, for example, information about the history of the charge states of the power battery 53 at the end of past operation of the electric vehicle 50 from the data management device 80, as information about the range of charge states that the user accepts for the power battery 53.

[0056] At the end of charging, the power battery 53 has the final target SOC determined by the power supply and demand management device 20. For example, if the information about the electric vehicle 50 collected by the data management device 80 includes a history of the final target SOC notified as a command value to the charge and discharge control device 51, this history information can be used to identify the distribution of the state of charge of the power battery 53 at past end-of-charging times. The power supply and demand management device 20 may acquire, for example, information about the history of past final target SOCs of the power battery 53 from the data management device 80 as information about the range of the state of charge of the power battery 53 that is acceptable to the user.

[0057] The power supply and demand management device 20 can estimate the user's tolerance range for the state of charge of the power battery 53 from the information acquired in step S107. For example, the power supply and demand management device 20 may estimate the lower limit of a range where the occurrence frequency is equal to or greater than a predetermined value in the distribution of the state of charge of the power battery 53 at the start of past charging shown in FIG. 3 as the lower limit of the user's tolerance range for the state of charge of the power battery 53. For example, the power supply and demand management device 20 may estimate the upper limit of a range where the occurrence frequency is equal to or greater than a predetermined value in the distribution of the state of charge of the power battery 53 at the end of past charging shown in FIG. 3 as the upper limit of the user's tolerance range for the state of charge of the power battery 53. The predetermined value may be different or the same at the start of charging and the end of charging.

[0058] The power supply and demand management device 20 estimates the charge amount of the power battery 53 required for the current charge based on the information acquired in steps S103 to S107 (step S109).

[0059] The power supply and demand management device 20 can estimate a usage pattern that will occur during the next operation of the electric vehicle 50, for example, from the usage history of the electric vehicle 50 during operation on days or periods whose attributes match or are similar to those of today, extracted from the information acquired in step S103. The power supply and demand management device 20 may estimate a decrease in the state of charge of the power battery 53 during the next operation of the electric vehicle 50 from the estimated usage pattern, and use the estimated decrease in the state of charge as the amount of charge of the power battery 53 required for the current charge. The required amount of charge of the power battery 53 estimated by the power supply and demand management device 20 is higher when the estimated decrease in the state of charge of the power battery 53 is large than when it is small. For example, when the tentative target SOC was changed at the user's request during the previous charge, the power supply and demand management device 20 may use the difference between the tentative target SOC after the previous change and the current state of charge of the power battery 53 as the amount of charge required for the power battery 53. For example, when the current state of charge of the power battery 53 is lower than the user's tolerance range, the power supply and demand management device 20 may select a value greater than the difference from the previous tentative target SOC as a candidate for the required charge amount of the power battery 53.

[0060] For example, if the user requested a change in the tentative target SOC before the previous charge of the power battery 53, the power supply and demand management device 20 extracts, from the information acquired in step S105, a difference Δ1 that is a history of changes to the tentative target SOC made by the user before the previous charge. The power supply and demand management device 20 adds together the difference Δ1 extracted for before the previous charge and the tentative target SOC set by the power supply and demand management device 20, just as with the tentative target SOC after change by the change unit 203. The power supply and demand management device 20 may use the sum of the difference Δ1 and the tentative target SOC as a candidate for the required charge amount of the power battery 53.

[0061] The power supply and demand management device 20 checks whether there is a history of the charge state of the power battery 53 being outside the user's tolerance range estimated from the information acquired in step S107, for example, between before the previous charge and before the current charge. The power supply and demand management device 20 can acquire the deviation amount Δ2 from a database in the data storage to which the deviation amount Δ2 is notified, as a history of the charge state of the power battery 53 being outside the user's tolerance range. When the power supply and demand management device 20 acquires the deviation amount Δ2 as the history between before the previous charge and before the current charge, the power supply and demand management device 20 adds the acquired deviation amount Δ2 to the tentative target SOC set by the power supply and demand management device 20. The power supply and demand management device 20 may use the sum of the deviation amount Δ2 and the tentative target SOC as a candidate for the required charge amount of the power battery 53.

[0062] In step S109, the power supply and demand management device 20 may estimate, for example, the highest charge amount candidate among the charge amount candidates obtained from the information acquired in steps S103 to S107 as the required charge amount of the power battery 53.

[0063] The power supply and demand management device 20 acquires information on the power demand of the building (step S111). The power demand of the building may be predicted, for example, using the current power consumption of power consumption elements excluding the electric vehicles and the storage batteries from the entire power supply and demand system 1 and accumulated past power consumption. The power supply and demand management device 20 acquires, for example, information on the power supply from the power grid 3 to the power supply and demand system 1 (step S113). The power supply and demand management device 20 can acquire information on the supplied power from, for example, contract information with a power company. Based on the acquired information on the power demand and power supply, the power supply and demand management device 20 predicts a power supply and demand plan that indicates changes in the power supply and demand of power consumption elements excluding the electric vehicles and the storage batteries from the entire power supply and demand system 1 (step S115).

[0064] The power supply and demand management device 20 may perform the procedures of steps S101 to S109 and the procedures of steps S111 to S115 in parallel, or may perform one procedure after the other.

[0065] The power supply and demand management device 20 sets a tentative target SOC of the power battery 53 for the current charge based on the estimated required charge amount of the power battery 53 and the predicted power supply and demand plan (step S117). The power supply and demand management device 20, for example, predicts the power demand of the building from the power supply and demand plan, calculates a target power amount for the entire group of the power supply and demand system 1 from the predicted power demand, and calculates a difference in power amount by subtracting the actual power amount of power consumed by the power consumption elements from the calculated target power amount. The difference in power amount corresponds to the power that can be supplied to the group of electric vehicles and the group of storage batteries of the power supply and demand system 1. The power supply and demand management device 20 can set the tentative target SOC of the power battery 53 based on the difference in power amount and the estimated required charge amount of the power battery 53.

[0066] As shown in FIG. 5 , the power supply and demand management device 20 acquires a history of changes to the tentative target SOC made by the user from the database in the data storage 210 (step S119). The power supply and demand management device 20 checks, based on the acquired history, whether the change unit 203 changed the tentative target SOC set by the power supply and demand management device 20 at the time of the previous charge in response to a user request (step S121). If the change unit 203 made a change (YES in step S121), the power supply and demand management device 20 sets, for example, a value f(Δ1) proportional to the difference Δ1 included in the change history for the previous charge, as a correction value ΔSOC1 of the set tentative target SOC (step S123). Thereafter, the process proceeds to step S129, which will be described later. The correction value ΔSOC1 can be, for example, a value obtained by multiplying the difference Δ1 by a coefficient based on a constant less than 1. If the change unit 203 did not make a change (NO in step S121), the process proceeds to step S129, which will be described later. In this case, the correction value ΔSOC1 of the tentative target SOC related to the change history of the tentative target SOC by the user becomes substantially zero.

[0067] The power supply and demand management device 20 checks whether the charge state of the power battery 53 has deviated from the user's tolerance range between the time before the last charge of the power battery 53 and the time before the current charge (step S125). The power supply and demand management device 20 can acquire the deviation amount Δ2 during operation of the electric vehicle 50 from the database of the data storage to which the deviation amount Δ2 has been notified as a history of changes in the charge state of the power battery 53 between the time before the last charge and the time before the current charge. The power supply and demand management device 20 can use the acquired deviation amount Δ2 to check whether the charge state of the power battery 53 has deviated from the user's tolerance range between the time before the last charge and the time before the current charge. If there is a history of the charge state being outside the tolerance range (YES in step S125), the power supply and demand management device 20 sets, for example, a value f(Δ2) proportional to the deviation amount Δ2 between the time before the last charge and the time before the current charge as the correction value ΔSOC2 of the set tentative target SOC (step S127). Then, the process proceeds to step S129. The correction value ΔSOC2 may be, for example, a time average value of the deviation amounts Δ2, which is obtained by dividing the sum ΣΔ2 of the deviation amounts Δ2 excluding zero from before the previous charge until before the current charge by the time from before the previous charge until before the current charge. If there is no history of deviations outside the allowable range (NO in step S125), the process proceeds to step S129. In this case, the correction value ΔSOC2 of the tentative target SOC related to the change history of the state of charge of the power battery 53 relative to the user's allowable range is substantially zero.

[0068] In step S129, the power supply and demand management device 20 determines a correction value for the tentative target SOC set in step S117 based on the correction value ΔSOC1 of step S123 and the correction value ΔSOC2 of step S127. For example, the power supply and demand management device 20 may determine the correction value for the tentative target SOC by adding the correction values ​​ΔSOC1 and ΔSOC2 together. The correction unit 206 of the power supply and demand management device 20 corrects the tentative target SOC set in step S117 with the correction value determined in step S129 (step S131). For example, the correction unit 206 may correct the tentative target SOC by adding the correction value of step S129 to the tentative target SOC set in step S117. The notification unit 201 of the power supply and demand management device 20 notifies the UI device 30 of the user of the electric vehicle 50 equipped with the power battery 53 to be charged of the tentative target SOC (step S133). If the tentative target SOC is corrected in step S131, the notification unit 201 notifies the user of the corrected tentative target SOC. Upon receiving this notification, the UI device 30 accepts a response to the request to change the tentative target SOC input by the user (step S201). If the accepted response requests a change to the tentative target SOC, the UI device 30 notifies the power supply and demand management device 20 of a difference Δ1 between the notified tentative target SOC and the changed tentative target SOC as a history of the user's request to change the tentative target SOC.

[0069] The power supply and demand management device 20 checks whether a request to change the tentative target SOC has been input to the UI device 30 based on whether the notification of the difference Δ1 has been received (step S135). If a request to change the tentative target SOC has been input to the UI device 30 (YES in step S135), the power supply and demand management device 20 adds the difference Δ1 of the received notification to the change request history database in the data storage 210 (step S137). Thereafter, the process proceeds to step S139, which will be described later. If a request to change the tentative target SOC has not been input to the UI device 30 (NO in step S135), the power supply and demand management device 20 proceeds to step S139.

[0070] In step S139, the power supply and demand management device 20 determines a final target state of charge based on the corrected tentative target SOC notified to the UI device 30 in step S133. If a request to change the tentative target SOC is input to the UI device 30 in step S135, the power supply and demand management device 20 determines the tentative target SOC changed by the change unit 203 as the final target state of charge. The changed tentative target SOC is obtained by adding the difference Δ1 notified from the UI device 30 to the corrected tentative target SOC notified to the UI device 30 in step S133. If a request to change the tentative target SOC is not input to the UI device 30 in step S135, the power supply and demand management device 20 determines the corrected tentative target SOC notified to the UI device 30 as the final target state of charge. This completes the series of steps of the state of charge management method according to the embodiment.

[0071] In this embodiment, even if the state of charge of the power battery 53, which is charged to a final target SOC determined based on the tentative target SOC, changes from what was expected before operation and falls outside the user's tolerance range, the history of this change is reflected in the tentative target SOC at the next charge. If the user changes the tentative target SOC during charging, the change history is reflected in the tentative target SOC through correction at the next charge. The change history of the tentative target SOC of the power battery 53 requested by the user is likely to reflect differences in the user's tolerance range for the state of charge of the power battery 53. The history of changes in the state of charge of the power battery 53 after charging is likely to reflect the results of power consumption of the power battery 53 by the electric vehicle 50 during operation. By correcting the tentative target SOC based on this history and determining the final target SOC to charge the power battery 53, the state of charge of the power battery 53 can be flexibly adjusted to accommodate situations in which the amount of power required for the power battery 53 changes.

[0072] [First Modification] In the embodiment, in step S127 of FIG. 5 , the power supply and demand management device 20 sets the value f(Δ2) proportional to the deviation Δ2 from before the previous charge of the power battery 53 until before the current charge as the correction value ΔSOC2 of the tentative target SOC. In the first modification of the embodiment, in step S129, the power supply and demand management device 20 estimates the deviation Δ2 from before the current charge of the power battery 53 until before the next charge, and determines the correction value ΔSOC2 of the tentative target SOC using the estimated deviation Δ2. As described in step S109, the power supply and demand management device 20 can estimate the usage pattern during the next operation of the electric vehicle 50 from the information acquired in step S103. The period from before the current charge of the power battery 53 until before the next charge corresponds to the next operation of the electric vehicle 50. The power supply and demand management device 20 can estimate a change in the state of charge of the power battery 53 from before the current charging of the power battery 53 to before the next charging, based on the estimated usage pattern during the next operation of the electric vehicle 50. The power supply and demand management device 20 can estimate, from the estimated change in the state of charge of the power battery 53, whether or not the state of charge of the power battery 53 from before the current charging to before the next charging will fall outside the user's tolerance range, and, if it does fall outside, the amount of deviation Δ2.

[0073] The power supply and demand management device 20 may use, for example, either the deviation amount Δ2 based on the past history described in the embodiment or the estimated deviation amount Δ2 described as a modification example, or both, to determine the correction value ΔSOC2 of the tentative target SOC. For example, when the deviation amount Δ2 based on the past history and the estimated deviation amount Δ2 have the same sign, the power supply and demand management device 20 may use the deviation amount Δ2 with the larger absolute value of the two deviation amounts Δ2 to determine the correction value ΔSOC2 of the tentative target SOC. For example, when the deviation amount Δ2 based on the past history and the estimated deviation amount Δ2 have different signs, the power supply and demand management device 20 may use the deviation amount Δ2 with a positive (+) sign to increase the correction value ΔSOC2 and the deviation amount Δ2 with a negative (−) sign to decrease the correction value ΔSOC2.

[0074] In the first modified example, the power supply and demand management device 20 estimates, before the next charge, a change in the state of charge after charging the power battery 53 when the power battery 53 is charged to the final target SOC. If the estimated change causes the state of charge of the power battery 53 to deviate from a predetermined range, the power supply and demand management device 20 corrects the tentative target SOC used to determine the final target SOC. The correction of the tentative target SOC reduces the degree to which the state of charge after charging the power battery 53 deviates from a predetermined range that is acceptable to the user. If the state of charge of the power battery 53 is expected to deviate from the user's acceptable range after the next charge of the power battery 53, the occurrence of this deviation can be suppressed by correcting the tentative target SOC before the next charge.

[0075] [Second Modification] When the state of charge of power battery 53 from before the current charge to before the next charge, as estimated in the first modification, exceeds the upper limit of the user's tolerance range, power supply and demand management device 20 may adjust the correction amount of the tentative target SOC as follows. The power supply and demand management device 20 may increase the correction amount of the tentative target SOC the longer the time during which the estimated state of charge of power battery 53 exceeds the upper limit of the user's tolerance range, compared to when the time is short. The power supply and demand management device 20 may increase the correction amount of the tentative target SOC the higher the ambient temperature of the power battery, compared to when the ambient temperature is low.

[0076] If the state of charge of the power battery 53 exceeds the upper limit of the user's tolerance range for a long period of time, the state of charge of the power battery 53 will remain high for a long period of time. When the state of charge of the power battery 53 is high, the power battery 53 is in a high voltage state, accelerating internal chemical changes. Even when the ambient temperature of the power battery 53 is high, internal chemical changes of the power battery 53 are accelerated. The more internal chemical changes are accelerated, the more the power battery 53 deteriorates. In the second modified example, the more accelerated the internal chemical changes of the power battery 53 are, the greater the correction amount of the tentative target SOC becomes. When the correction amount of the tentative target SOC becomes greater, the final target SOC of the power battery 53, which is determined based on the corrected tentative target SOC, decreases. In the second modified example, the more accelerated the internal chemical changes of the power battery 53 are, the greater the final target SOC of the power battery 53 is, thereby suppressing chemical changes of the power battery 53 and suppressing the progression of deterioration of the power battery 53.

[0077] [Third Modification] When the state of charge of power battery 53 from before the current charge to before the next charge, as estimated in the first modification, is below the lower limit of the range acceptable to the user, power supply and demand management device 20 may adjust the correction amount of the tentative target SOC as follows: The power supply and demand management device 20 may increase the correction amount of the tentative target SOC as the power consumption of electric vehicle 50 during operation, estimated from the surrounding environment of electric vehicle 50, is larger, compared to when the power consumption is small.

[0078] When the state of charge of the power battery 53 falls below the lower limit of the user's tolerance range, if the power consumption of the electric vehicle 50 estimated from the surrounding environment is high, the time when the state of charge of the power battery 53 falls below the lower limit of the user's tolerance range will arrive sooner than if the power consumption is low. In the third modified example, the greater the power consumption of the electric vehicle 50 estimated from the surrounding environment, the greater the correction amount of the tentative target SOC. As the correction amount of the tentative target SOC increases, the final target SOC of the power battery 53 determined based on the corrected tentative target SOC increases. As the final target SOC of the power battery 53 increases, the power consumption after charging to the final target SOC makes it less likely that the state of charge of the power battery 53 will fall below the lower limit of the user's tolerance range. In the third modified example, the more quickly the state of charge of the power battery 53 decreases, the greater the final target SOC of the power battery 53 can be increased, making it less likely that the state of charge of the power battery 53 will fall below the lower limit of the user's tolerance range.

[0079] The above-described embodiment and its modifications are merely examples of the present invention. Therefore, the present invention is not limited to the above-described embodiment, and various modifications can be made to the design and other aspects of the present invention without departing from the technical concept of the present invention.

[0080] 20 Electric power supply and demand management device (state of charge management device) 201 Notification unit 202 First acquisition unit 203 Change unit 204 Determination unit 205 Second acquisition unit 206 Correction unit 30 User interface device 50 Electric vehicle 51 Charging and discharging control device (state monitoring device) 53 Power battery 301 Reception unit 511 Detection unit Δ1 Difference (history of changes in the temporary target state of charge at the request of the user of the electric vehicle) Δ2 Deviation amount (history of changes in the state of charge after charging the power battery charged to the final target state of charge)

Claims

1. A charging state management method for electric vehicle power batteries, comprising setting a provisional target charging state for the power battery and determining the final target charging state of the power battery based on the provisional target charging state, Based on the history of changes in the provisional target charge state at the request of the electric vehicle user and the history of changes in the charge state after the power battery has been charged to the final target charge state, the provisional target charge state to be set when the power battery is charged next time is corrected. Charging status management method.

2. The charge state management method according to claim 1, wherein the history of changes in the charge state of the power battery after charging includes the amount of decrease in the charge state of the power battery after charging.

3. The charge state management method according to claim 1 or 2, wherein the history of changes in the charge state of the power battery after charging includes a history of the charge state of the power battery after charging deviating from a predetermined range.

4. A charging state management method according to claim 1 or 2, wherein the change in the charging state of the power battery after charging when it is charged to the final target charging state is estimated before the next charging, and if the charging state of the power battery deviates from a predetermined range in the estimated change, the provisional target charging state used to determine the final target charging state is corrected so as to reduce the degree of deviation.

5. The charge state management method according to claim 4, wherein, in the estimated change, if the charge state of the power battery exceeds the upper limit within the predetermined range, the provisional target charge state is reduced by correction, and the longer the time the charge state exceeds the upper limit, or the higher the ambient temperature of the power battery, the larger the amount of correction for the provisional target charge state is compared to when the time the charge state exceeds the upper limit is short or when the ambient temperature of the power battery is low.

6. The charging state management method according to claim 4, wherein, in the estimated change, if the charging state of the power battery falls below the lower limit within the predetermined range, the provisional target charging state is increased by correction, and the greater the estimated power consumption of the electric vehicle from the surrounding environment, the greater the amount of correction for the provisional target charging state compared to when the estimated power consumption of the electric vehicle is small.

7. A charging state management device that sets a provisional target charging state for the power battery of an electric vehicle when charging the power battery, and determines the final target charging state of the power battery based on the provisional target charging state, A first acquisition unit that acquires a request from the user of the electric vehicle to change the provisional target charging state, A modification unit that modifies the provisional target charging state in accordance with the content of the change request acquired by the first acquisition unit, A second acquisition unit acquires the change in the charge state after the power battery has been charged to the final target charge state, A correction unit corrects the provisional target charge state to be set when the power battery is charged next time, based on the history of changes in the provisional target charge state by the modification unit and the history of changes in the charge state acquired by the second acquisition unit. A charging status management device equipped with the following features.

8. A charging state management device that sets a provisional target charging state for the power battery of an electric vehicle when charging the power battery, A user interface device operated by the user of the electric vehicle, A condition monitoring device for monitoring the charge status of the aforementioned power battery and A charging state management system comprising: A notification unit that notifies the user of the provisional target charging state set by the charging state management device, A reception unit that receives a user's request to change the provisional target charging state notified by the notification unit, A first acquisition unit that acquires the change request received by the reception unit, A modification unit that modifies the provisional target charging state in accordance with the content of the change request acquired by the first acquisition unit, A determination unit that determines the final target charge state of the power battery based on the provisional target charge state, A detection unit for detecting changes in the charge state after the power battery has been charged to the final target charge state, A second acquisition unit acquires the change in charging state detected by the aforementioned detection unit, A correction unit corrects the provisional target charge state to be set when the power battery is charged next time, based on the history of changes in the provisional target charge state by the modification unit and the history of changes in the charge state acquired by the second acquisition unit. Equipped with, The reception unit is provided in the user interface device, the detection unit is provided in the status monitoring device, and the notification unit, the first acquisition unit, the change unit, the determination unit, the second acquisition unit and are provided in the charging status management device. Charging status management system.

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