Information processing device, program, and information processing method

Abstract

To provide an information processing device, a program, and an information processing method.SOLUTION: In a power system in which a management server and each of one or more power storage systems mutually transmit and receive information via a communication network, the management server 102 includes: a variation detection unit that detects variations of a charge state of a battery; an index value derivation unit that derives a value of a stress index; and an integrated value derivation unit that derives an integrated value of the value of the stress index in either a charge period in which the battery is charged or a discharge period in which the battery is discharged, based on the value of the stress index when the degree of variations satisfies a predetermined condition. The stress index indicates a ratio of the degree of a stress applied to the battery due to the variation detected by the variation detection unit to the degree of the stress applied to the battery due to charging / discharging when the battery is charged / discharged in one cycle of full charging and full discharging.SELECTED DRAWING: Figure 8

Description

[Technical field]

[0001] The present invention relates to an information processing device, a program, and an information processing method. [Background technology]

[0002] Patent Document 1 discloses a method for estimating battery deterioration using the SOC fluctuation range during charging and discharging. Non-Patent Document 1 discloses a battery stress control technology for electric vehicles. (Prior art document) (Patent Documents) (Patent Document 1) JP 2023-047106 A (Non-Patent Literature) (Non-Patent Document 1) Toshiyuki Sakamoto, "Grant-in-Aid for Scientific Research Research Results Report", [online], June 25, 2019, [searched July 3, 2023], Internet<URL:https: / / kaken.nii.ac.jp / file / KAKENHI-PROJECT-16K06975 / 16K06975seika.pdf> Summary of the Invention [Means for solving the problem]

[0003] In a first aspect of the present invention, an information processing device is provided. The information processing device includes, for example, a fluctuation detection unit that detects fluctuations in a state of charge (SOC) of a storage battery. The information processing device includes, for example, an index value derivation unit that derives a stress index value of the storage battery. In the information processing device, the stress index is, for example, an index indicating a ratio of a degree of stress given to the storage battery due to fluctuations detected by the fluctuation detection unit to a degree of stress given to the storage battery by charging and discharging when the storage battery is charged and discharged with full charging and full discharging being one cycle. The information processing device includes, for example, an integrated value derivation unit that derives an integrated value of the stress index value in either a charging period during which the storage battery is charged or a discharging period during which the storage battery is discharged, based on a stress index value when the degree of fluctuation satisfies a predetermined condition.

[0004] In any of the above information processing devices, the predetermined condition may include (i) a condition that the magnitude of the fluctuation is greater than a predetermined first threshold, (ii) a condition that the magnitude of the fluctuation in a reference period having a predetermined length is greater than the first threshold, or (iii) a condition that the ratio of the magnitude of the fluctuation to a reference value, which is the value of the state of charge of the storage battery at a reference point in time, is greater than a predetermined second threshold.

[0005] Any of the above information processing devices may include a determination unit that determines whether the degree of variation satisfies a predetermined condition.

[0006] In any of the above information processing devices, the judgment unit may judge that the degree of fluctuation does not satisfy the predetermined condition during the first period when (a) discharging of the storage battery is initiated at a reference time point or the storage battery is discharged at the reference time point, at least when (i) a first fluctuation amount, which is the absolute value of the difference between the minimum value of the state of charge of the storage battery and the reference value during a first period that is a period from the reference time point to a first discharging time point that is later than the reference time point and is the time point at which the state of charge of the storage battery becomes greater than a reference value, which is the value of the state of charge of the storage battery at the reference time point, is smaller than a predetermined first discharging threshold, or (ii) a ratio of the first fluctuation amount to the reference value is smaller than a predetermined second discharging threshold.

[0007] In any of the above information processing devices, the determination unit may determine that the degree of fluctuation satisfies a predetermined condition at least when (a) discharging of the storage battery is initiated at a reference time point or the storage battery is discharging at the reference time point, (iii) the discharge amount, which is the absolute value of the difference between the state of charge of the storage battery and the reference value, becomes greater than a predetermined third discharge threshold before the state of charge of the storage battery becomes greater than a reference value, which is the value of the state of charge of the storage battery at the reference time point, or (iv) the ratio of the discharge amount to the reference value becomes greater than a predetermined fourth discharge threshold before the state of charge of the storage battery becomes greater than the reference value.

[0008] In any of the above information processing devices, the index value derivation unit may derive the value of the stress index based on the absolute value of a difference between the reference value and a state of charge of the storage battery at a third discharging time point, which is the earliest time point at which charging of the storage battery starts after a second discharging time point, which is the time point at which the discharge amount becomes greater than a third discharging threshold or the ratio of the discharge amount to the reference value becomes greater than a fourth discharging threshold. In any of the above information processing devices, the index value derivation unit may derive the value of the stress index based on the absolute value of a difference between the reference value and a state of charge of the storage battery at a fourth discharging time point, which is the time point at which the charge / discharge state of the storage battery switches from a discharging tendency to a charging tendency after the third discharging time point.

[0009] Any of the above information processing devices may include a correspondence information acquisition unit that acquires correspondence information from a storage device that stores correspondence information indicating a correspondence relationship between a degree of variation in the state of charge of the storage battery and a degree of the stress index. The index value derivation unit may derive a value of the stress index based on the correspondence relationship and an absolute value of a difference between the state of charge of the storage battery and a reference value.

[0010] In any of the above information processing devices, the determination unit may update the reference time point when it is determined that the degree of the fluctuation satisfies a predetermined condition. The updated reference time point may be a second discharging time point, which is a time point when the discharge amount becomes larger than a third discharging threshold or a time point when the ratio of the discharge amount to the reference value becomes larger than a fourth discharging threshold, a third discharging time point, which is the earliest time point when charging of the storage battery starts after the second discharging time point, or a fourth discharging time point, which is a time point when the charge / discharge state of the storage battery changes from a discharging tendency to a charging tendency after the third discharging time point.

[0011] In any of the above information processing devices, the judgment unit may determine that the degree of fluctuation does not satisfy the predetermined condition during the second period when (b) charging of the storage battery is started at a reference time point or the storage battery is being charged at the reference time point, at least when (i) a second fluctuation amount, which is the absolute value of the difference between the maximum value of the state of charge of the storage battery and the reference value during a second period that is the period from the reference time point to a first charging time point that is later than the reference time point and is the time point at which the state of charge of the storage battery becomes smaller than a reference value, which is the value of the state of charge of the storage battery at the reference time point, is smaller than a predetermined first charging threshold, or (ii) a ratio of the second fluctuation amount to the reference value is smaller than a predetermined second charging threshold.

[0012] In any of the above information processing devices, the judgment unit may judge that the degree of fluctuation satisfies a predetermined condition at least when (b) charging of the storage battery is started at a reference time point or when the storage battery is charging at the reference time point, (iii) the charge amount, which is the absolute value of the difference between the charge state of the storage battery and the reference value, becomes greater than a predetermined third charging threshold before the charge state of the storage battery becomes smaller than a reference value, which is the value of the charge state of the storage battery at the reference time point, or (iv) the ratio of the charge amount to the reference value becomes greater than a predetermined fourth charging threshold before the charge state of the storage battery becomes smaller than the reference value.

[0013] In any of the above information processing devices, the index value derivation unit may derive the value of the stress index based on the absolute value of a difference between the reference value and a state of charge of the storage battery at a third charging time point, which is the earliest time point at which discharging of the storage battery starts after a second charging time point, which is the time point at which the charge amount becomes greater than a third charging threshold or the ratio of the charge amount to the reference value becomes greater than a fourth charging threshold. In any of the above information processing devices, the index value derivation unit may derive the value of the stress index based on the absolute value of a difference between the reference value and a state of charge of the storage battery at a fourth charging time point, which is the time point at which the charge / discharge state of the storage battery switches from a charging tendency to a discharging tendency after the third charging time point.

[0014] Any of the above information processing devices may include a correspondence information acquisition unit that acquires correspondence information from a storage device that stores correspondence information indicating a correspondence relationship between a degree of variation in the state of charge of the storage battery and a degree of the stress index. The index value derivation unit may derive a value of the stress index based on the correspondence relationship and an absolute value of a difference between the state of charge of the storage battery and a reference value.

[0015] In any of the above information processing devices, the determination unit may update the reference time point when it is determined that the degree of the fluctuation satisfies a predetermined condition. The updated reference time point may be a second charging time point, which is a time point when the charge amount becomes larger than a third charging threshold, or a time point when the ratio of the charge amount to the reference value becomes larger than a fourth charging threshold, a third discharging time point, which is the earliest time point when discharging of the storage battery starts after the second charging time point, or a fourth charging time point, which is a time point when the charge / discharge state of the storage battery changes from a charging tendency to a discharging tendency after the third discharging time point.

[0016] In any of the above information processing devices, the fluctuation detection unit may detect a fluctuation in the state of charge of each of the multiple storage batteries connected in parallel between the input terminal and the output terminal. In any of the above information processing devices, the index value derivation unit may derive a stress index value for each of the multiple storage batteries. In any of the above information processing devices, the integrated value derivation unit may derive an integrated value of the stress index value in either the charging period or the discharging period of each of the multiple storage batteries. In any of the above information processing devices, at least one of the multiple storage batteries may include multiple storage cells connected in series.

[0017] In a second aspect of the present invention, there is provided an information processing method. The information processing method includes, for example, a fluctuation detection step of detecting a fluctuation in a state of charge (SOC) of a storage battery. The information processing method includes, for example, an index value derivation step of deriving a value of a stress index. In the information processing method, the stress index is, for example, an index indicating a ratio of a degree of stress given to the storage battery by the fluctuation detected in the fluctuation detection step to a degree of stress given to the storage battery by charging and discharging when the storage battery is charged and discharged with full charging and full discharging being one cycle. The information processing method includes, for example, an integrated value derivation step of deriving an integrated value of the value of the stress index in either a charging period during which the storage battery is charged or a discharging period during which the storage battery is discharged, based on a value of the stress index when the degree of the fluctuation satisfies a predetermined condition. In the information processing method, the operating subject of each step may be a computer.

[0018] In a third aspect of the present invention, a program is provided. A computer-readable medium storing the above program may be provided. The computer-readable medium may be a non-transitory computer-readable medium or a computer-readable recording medium. The above program may be a program for causing a computer to function as any of the information processing devices according to the first aspect. The above program may be a program for causing a computer to execute any of the information processing methods according to the second aspect.

[0019] The above summary of the invention does not list all of the necessary features of the present invention. Also, subcombinations of these features may also be inventions. [Brief description of the drawings]

[0020] [Figure 1] 1 illustrates an example of a system configuration of a power system 100. [Diagram 2] 2 shows an example of the internal configuration of a power storage module 110. [Diagram 3] 2 illustrates an example of information processing in the management server 102. [Figure 4] 13 illustrates an example of a determination process when a discharging tendency occurs. [Diagram 5] 13A and 13B illustrate another example of the determination process when there is a tendency to discharge. [Figure 6] 13 illustrates an example of a determination process when a charging tendency occurs. [Figure 7] 13 illustrates an example of a determination process when there is a tendency to charge. [Figure 8] 2 illustrates an example of the internal configuration of the management server 102. [Figure 9] 13 illustrates an example of a process for generating correspondence information. [Figure 10] 2 illustrates an example of the internal configuration of the management server 102. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] The present invention will be described below through embodiments of the invention, but the following embodiments do not limit the invention according to the claims. Not all of the combinations of features described in the embodiments are essential to the solution of the invention. In addition, the embodiments will be described with reference to the drawings, but in the description of the drawings, the same reference numbers may be used for the same or similar parts, and duplicate descriptions may be omitted.

[0022] (Overview of power system 100) FIG. 1 illustrates an example of a system configuration of a power system 100. In this embodiment, the power system 100 includes a management server 102 and one or more power storage systems 104. In this embodiment, the management server 102 and each of the one or more power storage systems 104 can transmit and receive information to and from each other via a communication network 10. In this embodiment, each of the one or more power storage systems 104 is electrically connected to a load device 12 and / or a charging device 14. The power system 100 may include a plurality of power storage systems 104 connected in parallel to the load device 12 and / or the charging device 14. The power system 100 may include a plurality of power storage systems 104 connected in series to the load device 12 and / or the charging device 14.

[0023] In this embodiment, "A and B are electrically connected" is not limited to the case where A and B are physically connected directly. A conductive material may be interposed between A and B. Also, A and B do not have to be physically connected. For example, the input winding and the output winding of a transformer are not physically connected, but are electrically connected. Also, "A and B are connected in series" means that A and B are electrically connected in series, and "A and B are connected in parallel" means that A and B are electrically connected in parallel.

[0024] (Overview of each part related to the power system 100) In this embodiment, the communication network 10 transmits information between multiple devices. The communication network 10 may be a transmission path for wired communication, a transmission path for wireless communication, or a combination thereof. The communication network 10 may be the Internet, a dedicated line, a wireless communication network, or a combination thereof. The communication network 10 may include a P2P network such as an ad-hoc network.

[0025] The communication method in the wireless communication network may be a mobile communication method or a wireless data communication method. Examples of the mobile communication method include the 3G method, the LTE method, the 4G method, the 5G method, and the 6G method. Examples of the wireless data communication method include the wireless PAN method, the wireless LAN method, the wireless MAN method, and the wireless WAN method. The communication method in the wireless communication network may be various short-distance wireless communication methods.

[0026] In this embodiment, the load device 12 receives and consumes power output from one or more power storage systems 104. In this embodiment, the charging device 14 supplies power to each of the one or more power storage systems 104 and charges each of the one or more power storage systems 104.

[0027] In this embodiment, the management server 102 manages each of the one or more power storage systems 104. The management server 102 manages, for example, the degree of deterioration, remaining life (sometimes simply referred to as life), or replacement time of the power storage unit arranged in each of the one or more power storage systems 104. Details of the management server 102 will be described later.

[0028] In this embodiment, for the purpose of facilitating understanding of the management server 102, the details of the power system 100 will be described by taking as an example a case in which the power system 100 includes a single power storage system 104 and the management server 102 manages the single power storage system 104. However, the power system 100 is not limited to this embodiment. In other embodiments, the power system 100 may include a plurality of power storage systems 104 and the management server 102 may manage each of the plurality of power storage systems 104. Furthermore, a person skilled in the art who has come into contact with the description of this specification can understand that even when the power system 100 includes a plurality of power storage systems 104, the management server 102 can manage each of the plurality of power storage systems 104 by the same procedure as when the power system 100 includes a single power storage system 104.

[0029] In this embodiment, the power storage system 104 exchanges power with another device. In one embodiment, the power storage system 104 is electrically connected to the load device 12 and supplies power to the load device 12 (this may be referred to as discharging the power storage system 104). In another embodiment, the power storage system 104 is electrically connected to the charging device 14 and stores power supplied from the charging device 14 (this may be referred to as charging the power storage system 104).

[0030] The power storage system 104 is used, for example, in a power storage device, an electric appliance, a transportation device, etc. Examples of the power storage device include a stationary power storage device, a portable or mobile power storage device, etc. Examples of the transportation device include an electric car, a hybrid car, an electric two-wheeled vehicle, a railroad car, an airplane, an elevator, a crane, etc.

[0031] In this embodiment, the energy storage system 104 includes a connection terminal 106, a connection terminal 107, wiring 108 electrically connecting the connection terminals 106 and 107, an energy storage module 110 having a positive terminal 112 and a negative terminal 114, an energy storage module 120 having a positive terminal 122 and a negative terminal 124, and a system control unit 140.

[0032] In this embodiment, the details of the power storage system 104 will be described by taking as an example a case where the power storage module 110 and the power storage module 120 are connected in parallel using the wiring 108. However, the power storage system 104 is not limited to this embodiment. In other embodiments, the power storage system 104 may include a single power storage module, or may include three or more power storage modules. In still other embodiments, the power storage system 104 may include multiple power storage modules connected in series.

[0033] In this embodiment, the connection terminal 106 and the connection terminal 107 electrically connect the power storage system 104 to the load device 12 or the charging device 14. In this embodiment, the wiring 108 electrically connects the connection terminal 106 and the connection terminal 107 to the power storage module 110 and the power storage module 120, respectively.

[0034] In this embodiment, each of the storage modules 110 and 120 exchanges power with other devices. In one embodiment, each of the storage modules 110 and 120 supplies power to the load device 12. In another embodiment, each of the storage modules 110 and 120 stores power supplied from the charging device 14.

[0035] In this embodiment, each of the power storage module 110 and the power storage module 120 is detachably held in a housing of the power storage system 104. This allows each of the power storage module 110 and the power storage module 120 to be replaced individually.

[0036] In this embodiment, each of the power storage modules 110 and 120 can switch the connection relationship between the power storage unit of each power storage module and the wiring 108 based on a control signal from the system control unit 140 or a user operation. For example, each of the power storage modules 110 and 120 can electrically connect the power storage unit of each power storage module to the wiring 108 or electrically disconnect the power storage unit of each power storage module from the wiring 108 based on a control signal from the system control unit 140 or a user operation.

[0037] As a result, even if the voltage of a storage module to be newly installed in the storage system 104 differs from the voltage of a storage module already installed in the storage system 104, each of the multiple storage modules included in the storage system 104 can be replaced individually without worrying about damage or deterioration of the storage modules.

[0038] In this embodiment, the system control unit 140 controls each unit of the power storage system 104. The system control unit 140 switches the connection relationship between the wiring 108 and at least one of the power storage units of the power storage module 110 and the power storage module 120, for example.

[0039] The system control unit 140 determines the order in which the power storage units of the power storage modules are electrically connected to the wiring 108 based on, for example, the voltage of the power storage unit of each power storage module. In one embodiment, when the power storage system 104 is started to operate, and the state of the power storage system 104 starts from a charging state, the system control unit 140 electrically connects the power storage units of the power storage modules with a lower voltage to the wiring 108 first. On the other hand, when the power storage system 104 is started to operate, and the state of the power storage system 104 starts from a discharging state, the system control unit 140 electrically connects the power storage units of the power storage modules with a higher voltage to the wiring 108 first. In another embodiment, the system control unit 140 may determine the order in which the power storage units of the power storage modules are electrically connected to the wiring 108 based on the terminal voltage of each power storage module.

[0040] For example, the system control unit 140 transmits a signal for connecting the power storage unit to the wiring 108 to each power storage module in the determined order. Each power storage module electrically connects the power storage unit of each power storage module to the wiring 108 in accordance with the signal from the system control unit 140. The system control unit 140 may select the power storage module with the smallest voltage or SOC or the power storage module with the largest voltage or SOC, and transmit a signal for connecting the power storage unit to the wiring 108 only to the selected power storage module.

[0041] The system control unit 140 may monitor the state of the power storage system 104 and / or at least one of the power storage module 110 and the power storage module 120. Examples of the state include power ON / OFF, an operating state, etc. Examples of the operating state include charging, discharging, stopped, etc.

[0042] The system control unit 140 may collect information on the battery characteristics of each of the power storage module 110 and the power storage module 120. The information on the battery characteristics of each of the power storage module 110 and the power storage module 120 may be information on the battery characteristics of the power storage unit included in each of the power storage module 110 and the power storage module 120. Examples of the information on the battery characteristics of the power storage unit include information on at least one selected from a voltage value of the power storage unit, a current value flowing through the power storage unit, a battery capacity of the power storage unit, a State Of Charge (SOC) of the power storage unit, a temperature of the power storage unit, and a deterioration state of the power storage unit.

[0043] Examples of the information on the deterioration state of the power storage unit include information on the power storage unit at any time, such as (i) battery capacity in a fully charged state, (ii) SOC under a predetermined temperature condition, (iii) SOH (State Of Health), (iv) equivalent series resistance (DCR, sometimes referred to as internal resistance), (v) an integrated value of usage time during a period from an initial state or a predetermined timing to the arbitrary time, at least one of the number of charges during the period, the electric capacity charged during the period, the number of discharges during the period, the electric capacity discharged during the period, and the number of charge / discharge cycles during the period, and (vi) at least one of a temperature stress element and / or an overcurrent stress element during a period from an initial state or a predetermined timing to the arbitrary time. The information on the battery characteristics of the power storage unit may be stored by associating information on the deterioration state of the power storage unit with information on the time at which the information was acquired. The information on the battery characteristics of the power storage unit may store information on the deterioration state of the power storage unit at a plurality of times.

[0044] SOH [%] is expressed, for example, as the fully charged capacity at the time of degradation (e.g., the current fully charged capacity) [Ah]÷initial fully charged capacity [Ah]×100. There are no particular limitations on the method of calculating or estimating the SOH, but, for example, the SOH of the power storage unit is calculated or estimated based on at least one of the DC resistance value and the open circuit voltage value of the power storage unit. The SOH may be a value converted into a value under predetermined temperature conditions using an arbitrary conversion formula or the like.

[0045] The method for determining the deterioration state of the power storage unit is not particularly limited, and any currently known or future developed method can be used. In general, as the deterioration of the power storage unit progresses, the available battery capacity decreases and the equivalent series resistance increases. Therefore, for example, the deterioration state of the battery can be determined by comparing the current battery capacity, SOC, or equivalent series resistance with the initial battery capacity, SOC, or equivalent series resistance.

[0046] The SOC [%] is expressed, for example, as remaining capacity [Ah]÷full charge capacity [Ah]×100. There is no particular limitation on the method of calculating or estimating the SOC, but the SOC is calculated or estimated based on at least one of (i) the measurement result of the voltage of the power storage unit, (ii) IV characteristic data of the voltage of the power storage unit, and (iii) an integrated value of the current value of the power storage unit, for example. The SOC may be a value converted into a value under a predetermined temperature condition using an arbitrary conversion formula or the like.

[0047] The system control unit 140 may collect information on the specifications of each of the power storage module 110 and the power storage module 120, or the power storage units included in each power storage module. Examples of the information on the specifications of the power storage units include information on the type or model of the power storage unit, the connection state of the power storage unit, the type of charging method that can charge the power storage unit, the type of charging method that cannot charge the power storage unit, the rated battery capacity (sometimes referred to as rated capacity), the rated voltage, the rated current, the energy density, the maximum charge / discharge current, the charging characteristics, the charging temperature characteristics, the discharging characteristics, the discharging temperature characteristics, the self-discharge characteristics, the charge / discharge cycle characteristics, the equivalent series resistance in the initial state, the battery capacity in the initial state, the SOC [%] in the initial state, the storage voltage [V], and the like.

[0048] Examples of the charging method include the CCCV method, the CC method, and the trickle charging method. Examples of the connection state of the power storage unit include the type of unit cells constituting the power storage unit, the number of the unit cells, and the connection format of the unit cells. Examples of the connection format of the unit cells include the number of unit cells connected in series and the number of unit cells connected in parallel. The energy density is expressed as the volumetric energy density [Wh / m 3 ] or gravimetric energy density [Wh / kg].

[0049] The system control unit 140 may transmit and receive information to and from the management server 102 via the communication network 10. The system control unit 140 transmits, for example, information relating to the battery characteristics of at least one of the power storage module 110 and the power storage module 120 to the management server 102. The system control unit 140 may transmit, to the management server 102, information relating to the battery characteristics of the power storage unit included in at least one of the power storage module 110 and the power storage module 120.

[0050] The system control unit 140 may be realized by hardware or software. It may also be realized by a combination of hardware and software. In one embodiment, the system control unit 140 may be realized by an analog circuit, a digital circuit, or a combination of an analog circuit and a digital circuit. In another embodiment, the system control unit 140 may be realized by executing a program for controlling each unit of the system control unit 140 in a general information processing device including a data processing device having a CPU, a ROM, a RAM, a communication interface, etc.

[0051] The power system 100 may be an example of an information processing device. The management server 102 may be an example of an information processing device. The power storage module 110 may be an example of a storage battery. The power storage unit of the power storage module 110 may be an example of a storage battery. The power storage module 120 may be an example of a storage battery. The power storage unit of the power storage module 120 may be an example of a storage battery.

[0052] 2 shows an example of an internal configuration of the power storage module 110. The power storage module 120 may have a similar configuration to the power storage module 110.

[0053] In this embodiment, the power storage module 110 includes, for example, a power storage unit 210 having a positive terminal 212 and a negative terminal 214, a switching unit 230, a module control unit 240, a protection unit 250, and a balance correction unit 260. In this embodiment, the power storage unit 210 includes, for example, a power storage cell 222 and a power storage cell 224.

[0054] In the present embodiment, the details of the power storage module 110 will be described by taking as an example a case in which the positive electrode terminal 212 of the power storage unit 210 is electrically connected to the wiring 108 via the positive electrode terminal 112 of the power storage module 110 and the switching unit 230, and the negative electrode terminal 214 of the power storage unit 210 is electrically connected to the wiring 108 via the negative electrode terminal 114 of the power storage module 110. However, the power storage module 110 is not limited to this embodiment. In other embodiments, the negative electrode terminal 214 of the power storage unit 210 may be electrically connected to the wiring 108 via the negative electrode terminal 114 of the power storage module 110 and the switching unit 230, and the positive electrode terminal 212 of the power storage unit 210 may be electrically connected to the wiring 108 via the positive electrode terminal 112 of the power storage module 110.

[0055] In this embodiment, the power storage unit 210 exchanges power with another device. In one embodiment, the power storage unit 210 supplies power to the load device 12. In another embodiment, the power storage unit 210 stores power supplied from the charging device 14.

[0056] In this embodiment, the power storage cell 222 and the power storage cell 224 exchange power with other devices. In this embodiment, the power storage cell 222 and the power storage cell 224 are connected in series. The power storage cell 222 and the power storage cell 224 may be a secondary battery or a capacitor. At least one of the power storage cell 222 and the power storage cell 224 may be a lithium ion battery. At least one of the power storage cell 222 and the power storage cell 224 may further include a plurality of power storage cells connected in series, in parallel, or in a matrix shape inside the storage cell.

[0057] In this embodiment, the switching unit 230 is disposed between the wiring 108 and the power storage unit 210. In this embodiment, the switching unit 230 switches the connection state of the wiring 108 and the power storage unit 210 based on a signal generated by the module control unit 240. This makes it possible to electrically connect the power storage unit 210 to the wiring 108 or electrically disconnect the power storage unit 210 from the wiring 108. When the power storage module 110 is implemented in the power storage system 104, the power storage module 110 may be attached to the power storage system 104 in a state in which the power storage unit 210 and the wiring 108 are electrically disconnected by the switching unit 230. This can suppress damage or deterioration of the power storage module 110.

[0058] The switching unit 230 may be realized by hardware, software, or a combination of hardware and software. The switching unit 230 may be realized by an analog circuit, a digital circuit, or a combination of an analog circuit and a digital circuit. The switching unit 230 may have one or more elements. The switching unit 230 may have one or more switching elements. Each of the one or more switching elements may be disposed between the positive terminal 112 and the positive terminal 212, or between the negative terminal 114 and the negative terminal 214. Examples of the switching element include a relay, a thyristor, and a transistor. The thyristor may be a bidirectional thyristor (sometimes called a triac). The transistor may be a semiconductor transistor. The semiconductor transistor may be a bipolar transistor or a field effect transistor. The field effect transistor may be a MOSFET.

[0059] The module control unit 240 controls a current flowing between the power storage unit 210 of the power storage module 110 and the wiring 108. In this embodiment, the module control unit 240 controls the switching unit 230 so that the switching unit 230 electrically connects the power storage unit 210 and the wiring 108 when the terminal voltage of the switching unit 230 (in this embodiment, the voltage between the positive electrode terminal 112 and the positive electrode terminal 212) satisfies a predetermined condition. The switching unit 230 may electrically connect the power storage unit 210 and the wiring 108 by electrically connecting the power storage unit 210 and the positive electrode terminal 112.

[0060] On the other hand, when the terminal voltage of the switching unit 230 does not satisfy the predetermined condition, the switching unit 230 controls the switching unit 230 so as to electrically disconnect the power storage unit 210 and the wiring 108 or the positive terminal 112. The switching unit 230 may electrically disconnect the power storage unit 210 and the wiring 108 by electrically disconnecting the power storage unit 210 and the positive terminal 112.

[0061] The predetermined condition may be a condition that the absolute value of the terminal voltage of the switching unit 230 is within a predetermined range. The predetermined range may be 3V or less, 1V or less, 0.1V or less, 10mV or less, or 1mV or less. The predetermined range may be 0.5mV or more, or 1mV or more. The predetermined range may be 0.5mV or more and 3V or less. The predetermined range may be 1mV or more and 3V or less, 1mV or more and 1V or less, 1mV or more and 0.1V or less, 1mV or more and 10mV or less, 10mV or more and 1V or less, 10mV or more and 0.1V or less, or 0.1V or more and 1V or less. The terminal voltage of the switching unit 230 may be the voltage between the positive terminal 112 and the positive terminal 212, or may be the voltage between the wiring 108 and the power storage unit 210.

[0062] The predetermined range may be set based on the impedance of the power storage unit 210. The predetermined range may be set based on the rated current or allowable current of the power storage unit 210. The predetermined range may be set based on the impedance of the power storage unit 210 and the rated current or allowable current of the power storage unit 210. The predetermined range may be set based on the rated current or allowable current of an element having the smallest rated current or allowable current among the elements constituting the power storage module 110. The predetermined range may be set based on the impedance of the power storage module 110 and the rated current or allowable current of an element having the smallest rated current or allowable current among the elements constituting the power storage module 110.

[0063] As a result, when a power storage module is replaced, the wiring 108 and the power storage unit 210 of the newly mounted power storage module are maintained in an electrically disconnected state until the voltage difference between the newly mounted power storage module and the already mounted power storage module falls within a predetermined range. Then, when the voltage difference between the newly mounted power storage module and the already mounted power storage module falls within a predetermined range due to charging or discharging of the already mounted power storage module, the power storage unit of the newly mounted power storage module is electrically connected to the wiring 108. In this way, according to the present embodiment, the newly mounted power storage module is automatically electrically connected to the other power storage modules.

[0064] In this embodiment, the module control unit 240 receives a signal indicating that the terminal voltage of the power storage module 110 is smaller than the terminal voltages of the other power storage modules from the system control unit 140. When the module control unit 240 receives the above signal when the power storage system 104 transitions to a charging state, the module control unit 240 controls the switching unit 230 so that the switching unit 230 electrically connects the power storage unit 210 and the wiring 108. This makes it possible to efficiently charge the multiple power storage modules 110 connected in parallel.

[0065] In this embodiment, the module control unit 240 receives a signal indicating that the terminal voltage of the power storage module 110 is greater than the terminal voltages of the other power storage modules from the system control unit 140. When the module control unit 240 receives the signal when the power storage system 104 transitions to a discharging state, the module control unit 240 controls the switching unit 230 so that the switching unit 230 electrically connects the power storage unit 210 and the wiring 108. This allows the multiple power storage modules 110 connected in parallel to be efficiently discharged.

[0066] In this embodiment, the module control unit 240 receives a signal indicating that the terminal voltage of the power storage cell 222 or the power storage cell 224 is not within a predetermined range from the protection unit 250. Upon receiving the signal, the module control unit 240 controls the switching unit 230 so that the switching unit 230 electrically disconnects the power storage unit 210 and the wiring 108. This makes it possible to suppress deterioration or damage of the power storage unit 210 due to overcharging or overdischarging.

[0067] In this embodiment, the module control unit 240 accepts a user operation and receives an instruction from the user to turn on or off the switching unit 230. Upon receiving the user's instruction, the module control unit 240 controls the switching unit 230 in accordance with the instruction.

[0068] In this embodiment, the module control unit 240 may acquire information on the battery characteristics of the power storage unit 210. The module control unit 240 may output the information on the battery characteristics of the power storage unit 210 to an external device. This allows the external device to use the information on the battery characteristics of the power storage unit 210. Examples of the external device include the load device 12 and the charging device 14. The external device may be an output device that outputs information to a user.

[0069] The module control unit 240 may be realized by hardware or software. Also, it may be realized by a combination of hardware and software. In one embodiment, the module control unit 240 may be realized by an analog circuit, a digital circuit, or a combination of an analog circuit and a digital circuit. In another embodiment, the module control unit 240 may be realized by executing a program for controlling the module control unit 240 in a general information processing device including a data processing device having a CPU, a ROM, a RAM, a communication interface, etc.

[0070] In this embodiment, the protection unit 250 protects the power storage unit 210. In this embodiment, the protection unit 250 protects the power storage unit 210 from overcharging and overdischarging. When the protection unit 250 detects that the terminal voltage of the power storage cell 222 or the power storage cell 224 is not within a predetermined range, the protection unit 250 transmits a signal indicating that to the module control unit 240. The protection unit 250 may transmit information regarding the terminal voltage of the power storage unit 210 to the system control unit 140. The protection unit 250 may be realized by hardware, software, or a combination of hardware and software. The protection unit 250 may be realized by an analog circuit, a digital circuit, or a combination of an analog circuit and a digital circuit.

[0071] In this embodiment, the balance correction unit 260 equalizes the voltages of the multiple storage cells. The operating principle of the balance correction unit 260 is not particularly limited, and any balance correction device can be used. When the power storage unit 210 has three or more storage cells, the power storage module 110 may have multiple balance correction units 260. For example, when the power storage unit 210 has n (n is an integer equal to or greater than 2) storage cells, the power storage module 110 has n-1 balance correction units 260.

[0072] The balance correction unit 260 may be realized by hardware, software, or a combination of hardware and software. The balance correction unit 260 may be realized by an analog circuit, a digital circuit, or a combination of an analog circuit and a digital circuit. In one embodiment, the balance correction unit 260 is an active type balance correction device. The active type balance correction unit may be a balance correction unit that transfers charge between two storage cells via an inductor as described in Japanese Patent Application Publication No. 2006-067742, or may be a balance correction unit that transfers charge using a capacitor as described in Japanese Patent Application Publication No. 2012-210109. In another embodiment, the balance correction unit 260 may be a passive type balance correction device. The passive type balance correction device releases excess charge using, for example, an external resistor.

[0073] The power storage unit 210 may be an example of a storage battery. The power storage cell 222 may be an example of a storage battery. The power storage cell 224 may be an example of a storage battery.

[0074] (An example of another embodiment) In the present embodiment, the case where the power storage unit 210 has two storage cells connected in series has been described. However, the power storage unit 210 is not limited to this embodiment. In other embodiments, the power storage unit 210 may have three or more storage cells connected in series. Furthermore, the power storage unit 210 may have a plurality of storage cells connected in parallel, or a plurality of cells connected in a matrix.

[0075] Fig. 3 illustrates an example of information processing in the management server 102. An example of a procedure in which the management server 102 estimates the replacement time or lifespan of at least one of the power storage modules 110 and the power storage module 120 arranged in a specific power storage system 104 will be described with reference to Fig. 3. In this embodiment, in order to facilitate understanding of the above procedure, the details of the above procedure will be described using as an example a case in which the management server 102 estimates the replacement time or lifespan of each of the power storage modules 110 and the power storage module 120.

[0076] (Outline of estimation procedure) When a manufacturer or seller (sometimes referred to as a manufacturer, etc.) of a storage module (e.g., the above-mentioned storage module 110 and / or storage module 120) sets or guarantees the replacement time or lifespan of the storage module, the set value or guaranteed value of the replacement time or lifespan of the storage module is expressed, for example, using the number of charge / discharge cycles (sometimes referred to as the number of charge / discharge cycles or the number of cycles) at which the SOH of the storage module reaches a predetermined value when the storage module is repeatedly charged and discharged, with full charge and full discharge being one cycle. The number of cycles at which the SOH of the storage module reaches a predetermined value is called, for example, the cycle life.

[0077] In the above charge / discharge cycle, the SOC in the fully charged state of the power storage module may be 100% or may be an upper limit value of the SOC set by the manufacturer, etc. of the power storage module. In the above charge / discharge cycle, the SOC in the fully discharged state of the power storage module may be 0% or may be a lower limit value of the SOC set by the manufacturer, etc. of the power storage module.

[0078] In actual use of a storage module, it is rare for the storage module to be repeatedly charged and discharged, with full charge and full discharge being one cycle, and in many cases, the amount of variation in SOC during a single charge event or a single discharge event is less than 100%. The amount of variation in SOC during discharge is also called the depth of discharge (DOD). The depth of discharge indicates, for example, the ratio [%] of the amount of discharged electricity to the discharge capacity. The deeper the depth of discharge, the greater the stress on the storage module.

[0079] The charging event of the power storage module indicates, for example, the period from when charging of the power storage module starts to when charging ends, and the discharging event of the power storage module indicates, for example, the period from when discharging of the power storage module starts to when discharging ends.

[0080] The stress applied to the storage module differs between when the amount of SOC fluctuation during charging and discharging is relatively small and when the storage module is repeatedly charged and discharged, with full charging and full discharging being one cycle. In particular, when the amount of SOC fluctuation is very small, the electrodes of the storage module can function as a capacitor. In this case, almost no oxidation or reduction reactions occur in the electrodes of the storage module, and almost no deterioration of the storage module progresses.

[0081] In this way, the degree of deterioration of an energy storage module when the energy storage module is repeatedly charged and discharged, with full charge and full discharge constituting one cycle, differs from the degree of deterioration of the energy storage module in the actual usage environment of the energy storage module. Therefore, it is difficult to accurately estimate the degree of deterioration, remaining lifespan, or replacement time of an energy storage module that is actually being used, using the number of cycles set on the premise that the energy storage module is repeatedly charged and discharged, with full charge and full discharge constituting one cycle.

[0082] Therefore, according to this embodiment, a value (sometimes referred to as a stress index value) of an index (sometimes referred to as a stress index) indicating the ratio (B / A)[-] of the degree of stress (B) applied to the storage module due to fluctuations in SOC during use of the storage module to the degree of stress (A) applied to the storage module when the storage module is charged and discharged, with full charge and full discharge being one cycle, is derived. Also, according to this embodiment, the degree of deterioration, remaining life or replacement time of the storage module is estimated based on the above stress index value. More specifically, the degree of deterioration, remaining life or replacement time of the storage module is estimated based on an integrated value of the stress index value.

[0083] For example, if the stress index value in period Ta is 0.1, the stress value in period Tb following period Ta is 0.3, and the stress index value in period Tc following period Tb is 0.1, the integrated stress index value during periods Ta, Tb, and Tc is 0.5. Here, if the integrated stress index value corresponding to the fluctuation in the SOC of the power storage module during a specific period is N (N is a positive number), this means that deterioration has progressed by an amount equivalent to N cycles, where full charging and full discharging are considered to be one cycle, during that specific period, and a lifespan equivalent to that N cycles has been consumed.

[0084] Factors that cause deterioration of a power storage module include (i) cycle deterioration with an increase in the number of cycles, (ii) storage deterioration caused by leaving the power storage module in a state where the SOC is very high (e.g., a fully charged state) or in a state where the SOC is very high (e.g., a completely discharged state), and (iii) temperature deterioration due to a high temperature environment, but in many cases, cycle deterioration is predominant. Therefore, the degree of deterioration, remaining lifespan, or replacement time of the power storage module can be accurately estimated using the integrated value of the stress index value of the power storage module.

[0085] (Details of the estimation procedure) According to this embodiment, first, in step 322 (step may be abbreviated as S), the management server 102 acquires information indicating the SOC of each of the power storage modules 110 and 120 from the power storage system 104. In one embodiment, the management server 102 acquires information indicating the SOC of each of the power storage modules 110 and 120 at one or more times. In another embodiment, the management server 102 acquires information indicating the amount of change in the SOC of each of the power storage modules 110 and 120 from the previous time for each of the one or more times.

[0086] Next, the management server 102 detects fluctuations in the SOC of each of the power storage modules 110 and 120 based on the information acquired from the power storage system 104. The management server 102 detects fluctuations in the SOC of each power storage module based on, for example, the SOC value (sometimes referred to as a reference value) of each power storage module at a specific point in time (sometimes referred to as a reference point in time).

[0087] The management server 102 may update the reference time and / or the reference value at an appropriate timing. The procedure for updating the reference time and / or the reference value will be described later in detail.

[0088] Next, in S324, the management server 102 determines whether or not the degree of SOC fluctuation satisfies a predetermined condition (sometimes referred to as an integration condition) for each of the power storage module 110 and the power storage module 120. Examples of the degree of fluctuation include the magnitude of the fluctuation and the rate of the fluctuation.

[0089] The integration conditions include, for example, (i) that the magnitude of the fluctuation detected in S322 is greater than a predetermined threshold (may be referred to as a first threshold), (ii) that the magnitude of the fluctuation in a period having a predetermined length (may be referred to as a reference period) is greater than the first threshold, or (iii) that the ratio of the magnitude of the fluctuation to the reference value is greater than a predetermined threshold (may be referred to as a second threshold). This makes it possible to determine whether the degree of SOC fluctuation in each power storage module is relatively large.

[0090] The accumulation condition may be an example of a condition for determining a target of a process for deriving a stress index value in S326 described later (sometimes referred to as an index value derivation process).The accumulation condition may be an example of a condition for determining a target of a process for deriving an accumulated value of stress index values ​​in S328 described later (sometimes referred to as an accumulated value derivation process).

[0091] Next, in S326, the management server 102 derives the above-mentioned stress index value for each of the power storage module 110 and the power storage module 120. More specifically, the management server 102 derives a stress index value according to the degree of the fluctuation detected in S322 for each of the power storage module 110 and the power storage module 120. The management server 102 may generate and store, for each of one or more periods, information in which identification information for each period is associated with information indicating the stress index value for each period.

[0092] The management server 102 may derive a stress index value corresponding to the degree of fluctuation detected in S322 for each of the power storage modules 110 and 120, based on information (sometimes referred to as correspondence information) indicating a correspondence relationship between the degree of SOC fluctuation in each power storage module and the degree of stress index (e.g., stress index value). Examples of the correspondence information include (i) information indicating a function with the degree of SOC fluctuation as an explanatory variable and the stress index value as a response variable, and (ii) information indicating a table in which one or more categories related to the degree of SOC fluctuation are associated with one or more categories related to the stress index value. Details of the correspondence information will be described later.

[0093] In one embodiment, for example, for each of the power storage modules 110 and 120, (i) when it is determined in S324 that the degree of SOC fluctuation of the power storage module satisfies the integration condition, the management server 102 derives a stress index value of the power storage module, and (ii) when it is not determined in S324 that the degree of SOC fluctuation of the power storage module satisfies the integration condition, the management server 102 does not derive a stress index value of the power storage module. In another embodiment, the management server 102 may derive the stress index value of each of the power storage modules 110 and 120 regardless of the determination result in S324.

[0094] Next, in S328, the management server 102 derives an integrated value of the stress index value in either the charging period or the discharging period of each of the power storage modules 110 and 120. The charging period of each power storage module indicates the period during which the power storage module is charged. The discharging period of each power storage module indicates the period during which the power storage module is discharged.

[0095] When a power storage module is used for a relatively long period of time, the total length of the charging periods during that period is approximately equal to the total length of the discharging periods during that period. Similarly, when a power storage module is used for a relatively long period of time, the total amount of electricity discharged by the power storage module during that period due to discharging events during that period is approximately equal to the amount of electricity stored in the power storage module during that period due to charging events during that period. Therefore, even if an integrated value of the stress index value during both the charging period and the discharging period of each power storage module is not derived, the degree of deterioration, remaining life span, or replacement time of each power storage module can be appropriately managed.

[0096] According to one embodiment, in S326, for each of the power storage modules 110 and 120, (i) when it is determined in S324 that the degree of SOC fluctuation of the power storage module satisfies the integration condition, the management server 102 derives a stress index value of the power storage module, and (ii) when it is determined in S324 that the degree of SOC fluctuation of the power storage module does not satisfy the integration condition, the management server 102 does not derive a stress index value of the power storage module. In this case, in S328, the stress index value when it is determined that the degree of SOC fluctuation of each power storage module satisfies the integration condition is integrated.

[0097] According to another embodiment, in S326, the management server 102 derives the stress index values ​​of the power storage modules 110 and 120, regardless of the determination result in S324. In this case, in S328, the management server 102 derives the above-mentioned integrated value based on the stress index value when it is determined that the degree of SOC fluctuation of each power storage module 110 and 120 satisfies the integration condition. Specifically, the management server 102 integrates the stress index value when it is determined that the degree of SOC fluctuation of each power storage module satisfies the integration condition, for each power storage module 110 and 120. In this case, the stress index value when it is not determined that the degree of SOC fluctuation of each power storage module satisfies the integration condition is excluded from the integration process.

[0098] Next, in S330, the management server 102 estimates the degree of deterioration, remaining lifespan, or replacement time of each power storage module based on the integrated value of the stress index value of each power storage module derived in S328. As described above, when the integrated value of the stress index value corresponding to the fluctuation in the SOC of a power storage module in a specific period is N (N is a positive number), it means that deterioration has progressed by an amount equivalent to N cycles, where full charging and full discharging are considered to be one cycle, in the specific period, and the lifespan equivalent to the N cycles has been consumed.

[0099] In one embodiment, the life of each power storage module is represented by a cycle life. The cycle life of each power storage module is determined, for example, by the manufacturer of each power storage module. The management server 102 may obtain information indicating the cycle life of each power storage module from the manufacturer of each power storage module.

[0100] The management server 102 may estimate the remaining life of each power storage module based on the cycle life of each power storage module and the integrated value of the stress index value of each power storage module. For example, the remaining life of each power storage module is estimated by subtracting the integrated value of the stress index value of each power storage module from the cycle life of each power storage module.

[0101] The management server 102 may derive the amount of increase in the integrated value of the stress index value per unit time (sometimes referred to as the rate of increase in the integrated value) for each of the power storage module 110 and the power storage module 120. The management server 102 may estimate the replacement time for each power storage module based on the remaining life of each power storage module and the rate of increase in the integrated value of each power storage module. For example, the replacement time for each power storage module is estimated by dividing the remaining life of each power storage module by the rate of increase in the integrated value of each power storage module.

[0102] In another embodiment, the lifetime of each power storage module is determined by, for example, the SOH of each power storage module. The management server 102 derives the SOH of each power storage module, for example, in S326 or S328.

[0103] The management server 102 may generate and store, for each of one or more periods, information in which identification information for each period, an integrated value of the stress index value at a time representative of each period, and an SOH at a time representative of each period are associated with each other. The management server 102 may generate and store, for each of one or more periods, information in which identification information for each period, information indicating the stress index value for each period, information indicating the integrated value of the stress index value at a time representative of each period, and information indicating the SOH at a time representative of each period are associated with each other.

[0104] The management server 102 may derive a correspondence relationship between the integrated value of the stress index value and the SOH for each of the power storage module 110 and the power storage module 120. In one embodiment, the management server 102 generates and stores information indicating a function with the integrated value of the stress index value as an explanatory variable and the SOH as a response variable. In another embodiment, the management server 102 generates and stores information indicating a table in which one or more categories related to the integrated value of the stress index value are associated with one or more categories related to the SOH.

[0105] The management server 102 derives an integrated value of the stress index value of each power storage module when the SOH of each power storage module reaches a predetermined value (sometimes referred to as an integrated value at the end of the life or when it is time to replace the module) based on the correspondence between the integrated value of the stress index value and the SOH. The above-mentioned predetermined value may be a value set by the manufacturer or the like of each power storage module as the SOH of each power storage module at the end of its life or when it is time to replace the module.

[0106] The management server 102 may estimate the remaining life of each power storage module based on the integrated value at the end of the life or when it is time to replace each power storage module and the integrated value of the current stress index value of each power storage module. For example, the remaining life of each power storage module is estimated by subtracting the integrated value of the current stress index value of each power storage module from the integrated value at the end of the life or when it is time to replace each power storage module.

[0107] The management server 102 may derive the amount of increase in the integrated value of the stress index value per unit time (sometimes referred to as the rate of increase in the integrated value) for each of the power storage module 110 and the power storage module 120. The management server 102 may estimate the replacement time for each power storage module based on the remaining life of each power storage module and the rate of increase in the integrated value of each power storage module. For example, the replacement time for each power storage module is estimated by dividing the remaining life of each power storage module by the rate of increase in the integrated value of each power storage module.

[0108] S322 may be an example of a fluctuation detection step, S324 may be an example of a determination step, S326 may be an example of an index value derivation step, and S328 may be an example of an integrated value derivation step.

[0109] (An example of another embodiment) In the present embodiment, the details of the information processing in the management server 102 have been described by taking as an example a case in which it is determined in S324 whether the degree of SOC fluctuation satisfies the integration condition for each of the power storage module 110 and the power storage module 120. However, the information processing in the management server 102 is not limited to this embodiment. According to another embodiment, a process of determining whether the integration condition is met may be performed in S326. According to yet another embodiment, a process of determining whether the integration condition is met may be performed in S328.

[0110] Fig. 4 shows an example of a determination process for a power storage module 110 that is tending to discharge. In Fig. 4, a solid line 420 indicates a fluctuation history of the SOC of the power storage module 110. An example of the determination process during the discharging period of the power storage module 110 will be described with reference to Fig. 4. Specifically, an example of the determination process by the management server 102 will be described with reference to a case where the management server 102 determines that the degree of fluctuation in the SOC of the power storage module 110 satisfies the above-mentioned integration condition.

[0111] In this embodiment, an example of the determination process by the management server 102 will be described using as an example a case where the discharge of the power storage module 110 starts at the reference time point described above, or a case where the power storage module 110 is discharged at the reference time point described above. Note that the determination process for the power storage module 120 tending to discharge can be executed by a procedure similar to that of the determination process for the power storage module 110 tending to discharge.

[0112] (time ta~time tb) According to this embodiment, first, at time ta, the power storage system 104 is powered on. At this time, the SOC of the power storage module 110 arranged in the power storage system 104 is Sa [%]. Then, at time tb, the power storage module 110 starts discharging.

[0113] In this embodiment, the management server 102 sets the time tb as the reference time point that is set first after the power storage system 104 is turned on. The management server 102 may set the time tb as the reference time point regarding the discharge of the power storage module 110. In addition, Sa, which is the SOC of the power storage module 110 at the time tb, is set as the reference value.

[0114] (Time tb ~ Time tc) After the discharge of the power storage module 110 starts at time tb, the SOC of the power storage module 110 decreases, for example, by repeatedly decreasing and increasing, and becomes smaller than Sta [%] at time tc. During part of the period from time tb to time tc, no fluctuation in the SOC may be observed. In another embodiment, the SOC of the power storage module 110 may decrease monotonically during the period from time tb to time tc.

[0115] According to this embodiment, in the period from time tb to time tc, the SOC of the power storage module 110 is equal to or smaller than Sa. Also, in the period from time tb to time tc, the SOC of the power storage module 110 is greater than or equal to Sta.

[0116] In one embodiment, Sta is set so that the absolute value of the difference between Sta and Sa, which is a reference value during the period from time tb to time tc, is a predetermined value (sometimes referred to as a third discharge threshold). According to this embodiment, after the discharge of the power storage module 110 starts at time tb, the absolute value of the difference between the SOC of the power storage module 110 and the reference value Sa (sometimes referred to as a discharge amount) becomes greater than the third discharge threshold before the SOC of the power storage module 110 becomes greater than the reference value Sa.

[0117] At this time, the management server 102 may determine that the degree of fluctuation in the SOC of the power storage module 110 during the period from time tb to time tc satisfies the above-described integration condition. The management server 102 may also determine that the degree of fluctuation in the SOC of the power storage module 110 during the period from time tb to time tc satisfies the integration condition related to discharging.

[0118] In another embodiment, Sta is set so that the ratio of the absolute value of the difference between Sa and Sta to the above-mentioned reference value Sa (i.e., (Sa-Sta) / Sa) becomes a predetermined value (sometimes referred to as a fourth discharge threshold). According to this embodiment, after discharging of the energy storage module 110 starts at time tb, the ratio of the absolute value of the difference between Sa and Sta to the reference value Sa becomes greater than the fourth discharge threshold before the SOC of the energy storage module 110 becomes greater than the reference value Sa.

[0119] At this time, the management server 102 may determine that the degree of fluctuation in the SOC of the power storage module 110 during the period from time tb to time tc satisfies the above-described integration condition. The management server 102 may also determine that the degree of fluctuation in the SOC of the power storage module 110 during the period from time tb to time tc satisfies the integration condition related to discharging.

[0120] (Time tc~Time td) Thereafter, as the power storage module 110 is discharged, the SOC of the power storage module 110 also decreases. According to this embodiment, when the SOC of the power storage module 110 reaches Sd [%] at time td, the discharging of the power storage module 110 ends and charging of the power storage module 110 starts. In the embodiment shown in Fig. 4, time td is the earliest time point at which charging of the power storage module 110 starts after time tc. As described above, time tc is the time point at which it is determined that the degree of fluctuation in the SOC of the power storage module 110 satisfies the integration condition.

[0121] (time td~time te) According to this embodiment, after charging of the power storage module 110 starts at time td, charging and discharging of the power storage module 110 are repeated, and as a result, the SOC of the power storage module 110 becomes smaller than Sd at time te. During part of the period from time td to time te, no fluctuation in the SOC may be observed.

[0122] According to this embodiment, in the period from time td to time te, the SOC of the power storage module 110 is smaller than Std [%]. Also, in the period from time td to time te, the SOC of the power storage module 110 is larger than or equal to Sd. In this case, the absolute value Vde [%] of the difference between the maximum value of the SOC of the power storage module 110 in the period from time td to time te and Sd is smaller than the absolute value of the difference between Std and Sd.

[0123] In one embodiment, Std is set so that the absolute value of the difference between Sd and Std is a predetermined value (sometimes referred to as a first charging threshold). According to this embodiment, the absolute value Vde of the difference between the maximum SOC of the power storage module 110 in the period from time td to time te and Sd is smaller than the first charging threshold. At this time, the management server 102 may determine that the degree of fluctuation in the SOC of the power storage module 110 in the period from time td to time te does not satisfy the integration condition for charging.

[0124] In another embodiment, Std is set so that the ratio of the absolute value of the difference between Sd and Std to Sd (i.e., (Std-Sd) / Sd) is a predetermined value (sometimes referred to as the second charging threshold). According to this embodiment, the ratio of Vde to Sd is smaller than the second charging threshold. At this time, the management server 102 may determine that the degree of fluctuation in the SOC of the storage module 110 during the period from time td to time te does not satisfy the accumulation condition for charging.

[0125] (time te~time tf) Thereafter, the SOC of the power storage module 110 decreases as the power storage module 110 discharges. According to this embodiment, when the SOC of the power storage module 110 reaches Sf [%] at time tf, the discharging of the power storage module 110 ends and charging of the power storage module 110 starts.

[0126] (time tf~time tg) According to this embodiment, after charging of the power storage module 110 starts at time tf, charging and discharging of the power storage module 110 are repeated, and as a result, the SOC of the power storage module 110 becomes greater than Stf [%] at time tg. During part of the period from time tf to time tg, no fluctuation in the SOC may be observed. In other embodiments, the SOC of the power storage module 110 may monotonically increase during the period from time tf to time tg.

[0127] According to this embodiment, in the period from time tf to time tg, the SOC of the power storage module 110 is equal to or greater than Sf. Also, in the period from time tf to time tg, the SOC of the power storage module 110 is smaller than or equal to Stf.

[0128] In one embodiment, Stf is set so that the absolute value of the difference between Sf and Stf is a predetermined value (sometimes referred to as a third charging threshold). According to this embodiment, after charging of the power storage module 110 starts at time tf, the absolute value of the difference between the SOC of the power storage module 110 and Sf (sometimes referred to as a charging amount) becomes greater than the third charging threshold before the SOC of the power storage module 110 becomes smaller than Sf.

[0129] At this time, the management server 102 may determine that the degree of fluctuation in the SOC of the power storage module 110 during the period from time tf to time tg satisfies the above-described integration condition. The management server 102 may determine that the degree of fluctuation in the SOC of the power storage module 110 during the period from time tf to time tg satisfies the integration condition related to charging.

[0130] In another embodiment, Stf is set so that the ratio of the absolute value of the difference between Sf and Stf to Sf (i.e., (Stf-Sf) / Sf) is a predetermined value (sometimes referred to as a fourth charging threshold). According to this embodiment, after charging of the power storage module 110 starts at time tf, the ratio of the absolute value of the difference between Sf and Stf to Sf becomes greater than the fourth charging threshold before the SOC of the power storage module 110 becomes smaller than Sf.

[0131] At this time, the management server 102 may determine that the degree of fluctuation in the SOC of the power storage module 110 during the period from time tf to time tg satisfies the above-described integration condition. The management server 102 may determine that the degree of fluctuation in the SOC of the power storage module 110 during the period from time tf to time tg satisfies the integration condition related to charging.

[0132] According to this embodiment, the integration condition for discharging is satisfied in the period from time tb to time tf, and the integration condition for charging is satisfied in the period from time tf to time tg. Therefore, for example, at time tg, the management server 102 determines that the charge / discharge state of the power storage module 110 at time tf has switched from a discharging tendency to a charging tendency.

[0133] At time tg, the management server 102 may decide to update the reference time point. Specifically, the management server 102 sets time tf as a new reference time point. The management server 102 may set time tf as a reference time point for charging the power storage module 110. In addition, Sf, which is the SOC of the power storage module 110 at time tf, is set as a reference value.

[0134] (time tg~time th) Thereafter, the SOC of the power storage module 110 also increases as the power storage module 110 is charged. According to this embodiment, at time th, the SOC of the power storage module 110 becomes greater than Sa.

[0135] As described above, according to the present embodiment, after the discharge of the power storage module 110 starts at time tb, the SOC of the power storage module 110 decreases from Sa to Sf while repeatedly slightly increasing and decreasing. Thereafter, the SOC of the power storage module 110 increases from Sf to Sa while repeatedly slightly increasing and decreasing. Sf, which is the SOC of the power storage module 110 at time tf, may be the minimum value of the SOC of the power storage module 110 during the period from time tb to time th.

[0136] In this embodiment, the management server 102 detects that the SOC of the power storage module 110 has changed from Sa to Sf in the period from time tb to time th. The management server 102 derives a stress index value for the period from time tb to time th based on the detected amount of change in SOC and the above-mentioned correspondence information. As a result, a stress index value for the discharge period (i.e., the period from time tb to time tf) of the period from time tb to time th is derived.

[0137] For example, the management server 102 accumulates one or more stress index values ​​and manages the degree of deterioration, remaining life span, or replacement time of the power storage module 110 based on the accumulated value. The management server 102 may derive the accumulated value of the stress index values ​​every time a new stress index value is derived, or may derive the accumulated value of one or more stress index values ​​derived within an arbitrary period.

[0138] Time tb in FIG. 4 may be an example of a reference time point for discharging the power storage module 110. Sa in FIG. 4 may be an example of a reference value for discharging the power storage module 110. Time tc in FIG. 4 may be an example of a second discharging time point. Time td in FIG. 4 may be an example of a third discharging time point. Time tf in FIG. 4 may be an example of a fourth discharging time point. Time tf in FIG. 4 may be an example of a reference time point for charging the power storage module 110. Sf in FIG. 4 may be an example of a reference value for charging the power storage module 110.

[0139] Time td in Fig. 4 may be an example of a reference time point regarding charging of the power storage module 110. Sd in Fig. 4 may be an example of a reference value regarding charging of the power storage module 110. Time te in Fig. 4 may be an example of a first charging time point. The period from time td to time te in Fig. 4 may be an example of a second period. Vde in Fig. 4 may be an example of a second fluctuation amount.

[0140] (An example of another embodiment) In the present embodiment, an example of the determination process by the management server 102 has been described using as an example a case where the reference time point that is set first after the power storage system 104 is turned on is time tb. However, the determination process by the management server 102 is not limited to this embodiment. In other embodiments, the time ta may be set as the reference time point that is set first after the power storage system 104 is turned on.

[0141] In the present embodiment, an example of the process of determining whether the accumulation condition is met by the management server 102 has been described, taking as an example a case in which the reference time point is updated when the charge / discharge state of the power storage module 110 shifts from a discharging tendency to a charging tendency. However, the determination process by the management server 102 is not limited to this embodiment. In other embodiments, the reference time point may be updated when it is determined that the degree of variation in the SOC of the power storage module 110 satisfies the accumulation condition. For example, time tc, time td, or time te may be set as a new reference time point.

[0142] The management server 102 may detect a fluctuation in the SOC of the power storage module 110 each time the reference time point is updated. The management server 102 may derive an amount of fluctuation in the SOC of the power storage module 110 each time the reference time point is updated. The management server 102 may derive a stress index value each time the reference time point is updated.

[0143] Fig. 5 shows an outline of another example of the determination process for the power storage module 110 that is tending to discharge. In Fig. 5, a solid line 520 indicates the fluctuation history of the SOC of the power storage module 110. An example of the determination process during the discharging period of the power storage module 110 will be described with reference to Fig. 5. Specifically, an example of the determination process by the management server 102 will be described with reference to a case where the management server 102 determines that the degree of fluctuation in the SOC of the power storage module 110 does not satisfy the above-mentioned integration condition.

[0144] In this embodiment, an example of the determination process by the management server 102 will be described using as an example a case where the discharge of the power storage module 110 starts at the reference time point described above, or a case where the power storage module 110 is discharged at the reference time point described above. Note that the determination process for the power storage module 120 tending to discharge can be executed by a procedure similar to that of the determination process for the power storage module 110 tending to discharge.

[0145] (time ta~time tb) According to this embodiment, first, at time ta, the power storage system 104 is powered on. At this time, the SOC of the power storage module 110 arranged in the power storage system 104 is Sa [%]. Then, at time tb, the power storage module 110 starts discharging.

[0146] In this embodiment, the management server 102 sets the time tb as the reference time point that is set first after the power storage system 104 is turned on. The management server 102 may set the time tb as the reference time point regarding the discharge of the power storage module 110. In addition, Sa, which is the SOC of the power storage module 110 at the time tb, is set as the reference value.

[0147] (time tb ~ time ti) After the discharge of the power storage module 110 starts at time tb, for example, charging and discharging of the power storage module 110 are repeated. According to this embodiment, the SOC of the power storage module 110 reaches the minimum value Sj [%] in the period from time tb to time ti at time tj, and then becomes greater than Sa at time ti. During part of the period from time tb to time ti, no fluctuation in the SOC may be observed.

[0148] According to this embodiment, in the period from time tb to time ti, the SOC of the power storage module 110 is smaller than or equal to Sa. Also, in the period from time tb to time ti, the SOC of the power storage module 110 is larger than Sta [%].

[0149] In one embodiment, Sta is set so that the absolute value of the difference between Sta and Sa, which is a reference value during the period from time tb to time ti, is a predetermined value (sometimes referred to as a first discharge threshold). According to this embodiment, the absolute value Vbi of the difference between Sa and Sj, which is the minimum value of the SOC of the power storage module 110 during the period from time tb to time ti, is smaller than the first discharge threshold. The first discharge threshold may be the same as the third discharge threshold, or may be smaller than the third discharge threshold, or may be larger than the third discharge threshold.

[0150] At this time, the management server 102 may determine that the degree of fluctuation in the SOC of the power storage module 110 does not satisfy the above-mentioned integration condition during the period from time tb to time ti. The management server 102 may determine that the degree of fluctuation in the SOC of the power storage module 110 does not satisfy the integration condition related to discharge during the period from time tb to time ti.

[0151] In another embodiment, Sta is set so that the ratio of the absolute value of the difference between Sa and Sta to the above-mentioned reference value Sa (i.e., (Sa-Sta) / Sa) is a predetermined value (sometimes referred to as the second discharge threshold). According to this embodiment, the ratio of the above-mentioned Vbi to the reference value Sa is smaller than the second discharge threshold. The second discharge threshold may be the same as the fourth discharge threshold, or may be smaller than the fourth discharge threshold, or may be greater than the fourth discharge threshold.

[0152] At this time, the management server 102 may determine that the degree of fluctuation in the SOC of the power storage module 110 does not satisfy the above-mentioned integration condition during the period from time tb to time ti. The management server 102 may determine that the degree of fluctuation in the SOC of the power storage module 110 does not satisfy the integration condition related to discharge during the period from time tb to time ti.

[0153] Time ti in Fig. 5 may be an example of a first discharge point in time. The period from time tb to time ti in Fig. 5 may be an example of a first period. Vbi in Fig. 5 may be an example of a first fluctuation amount.

[0154] Fig. 6 shows an example of a determination process for the power storage module 110 that is in a charging tendency. In Fig. 6, a solid line 620 indicates a fluctuation history of the SOC of the power storage module 110. An example of the determination process during the charging period of the power storage module 110 will be described with reference to Fig. 6. Specifically, an example of the determination process by the management server 102 will be described with reference to a case where the management server 102 determines that the degree of fluctuation in the SOC of the power storage module 110 satisfies the above-mentioned integration condition.

[0155] In this embodiment, an example of the determination process by the management server 102 will be described using as an example a case where charging of the power storage module 110 is started at the above-mentioned reference time point, or a case where the power storage module 110 is being charged at the reference time point. Note that the determination process for the power storage module 120 tending to be charged can be executed by a procedure similar to that of the determination process for the power storage module 110 tending to be charged.

[0156] (time ta~time tb) According to this embodiment, first, at time ta, the power storage system 104 is powered on. At this time, the SOC of the power storage module 110 arranged in the power storage system 104 is Sa [%]. Then, at time tb, charging of the power storage module 110 starts.

[0157] In this embodiment, the management server 102 sets the time tb as the reference time point that is set first after the power storage system 104 is turned on. The management server 102 may set the time tb as the reference time point for charging the power storage module 110. In addition, Sa, which is the SOC of the power storage module 110 at the time tb, is set as a reference value.

[0158] (Time tb ~ Time tc) After charging of the power storage module 110 starts at time tb, the SOC of the power storage module 110 increases while repeatedly increasing and decreasing, and becomes greater than Sta [%] at time tc. During part of the period from time tb to time tc, no fluctuation in the SOC may be observed. In another embodiment, the SOC of the power storage module 110 may increase monotonically during the period from time tb to time tc.

[0159] According to this embodiment, in the period from time tb to time tc, the SOC of the power storage module 110 is equal to or greater than Sa. Also, in the period from time tb to time tc, the SOC of the power storage module 110 is smaller than or equal to Sta.

[0160] In one embodiment, Sta is set so that the absolute value of the difference between Sta and Sa, which is a reference value during the period from time tb to time tc, is a predetermined value (sometimes referred to as a third charging threshold). According to this embodiment, after charging of the power storage module 110 starts at time tb, the absolute value of the difference between the SOC of the power storage module 110 and the reference value Sa (sometimes referred to as the charge amount) becomes greater than the third charging threshold before the SOC of the power storage module 110 becomes smaller than the reference value Sa.

[0161] At this time, the management server 102 may determine that the degree of fluctuation in the SOC of the power storage module 110 during the period from time tb to time tc satisfies the above-described integration condition. The management server 102 may also determine that the degree of fluctuation in the SOC of the power storage module 110 during the period from time tb to time tc satisfies the integration condition related to charging.

[0162] In another embodiment, Sta is set so that the ratio of the absolute value of the difference between Sa and Sta to the above-mentioned reference value Sa (i.e., (Sta-Sa) / Sa) is a predetermined value (sometimes referred to as a fourth charging threshold). According to this embodiment, after charging of the power storage module 110 starts at time tb, the ratio of the absolute value of the difference between Sa and Sta to the reference value Sa becomes greater than the fourth charging threshold before the SOC of the power storage module 110 becomes smaller than the reference value Sa.

[0163] At this time, the management server 102 may determine that the degree of fluctuation in the SOC of the power storage module 110 during the period from time tb to time tc satisfies the above-described integration condition. The management server 102 may also determine that the degree of fluctuation in the SOC of the power storage module 110 during the period from time tb to time tc satisfies the integration condition related to charging.

[0164] (Time tc~Time td) Thereafter, as the power storage module 110 is charged, the SOC of the power storage module 110 also increases. According to this embodiment, when the SOC of the power storage module 110 reaches Sd [%] at time td, charging of the power storage module 110 ends and discharging of the power storage module 110 starts. In the embodiment shown in Fig. 6, time td is the earliest time point at which discharging of the power storage module 110 starts after time tc. As described above, time tc is the time point at which it is determined that the degree of fluctuation in the SOC of the power storage module 110 satisfies the integration condition.

[0165] (time td~time te) According to this embodiment, after the discharge of the power storage module 110 starts at time td, the power storage module 110 is repeatedly discharged and charged, and as a result, the SOC of the power storage module 110 becomes greater than Sd at time te. During part of the period from time td to time te, no fluctuation in the SOC may be observed.

[0166] According to this embodiment, in the period from time td to time te, the SOC of the power storage module 110 is greater than Std [%]. Also, in the period from time td to time te, the SOC of the power storage module 110 is less than or equal to Sd. In this case, the absolute value Vde [%] of the difference between the minimum value of the SOC of the power storage module 110 and Sd in the period from time td to time te is smaller than the absolute value of the difference between Std and Sd.

[0167] In one embodiment, Std is set so that the absolute value of the difference between Sd and Std is a predetermined value (sometimes referred to as a first discharge threshold). According to this embodiment, the absolute value Vde of the difference between the minimum value of the SOC of the power storage module 110 in the period from time td to time te and Sd is smaller than the first discharge threshold. At this time, the management server 102 may determine that the degree of fluctuation in the SOC of the power storage module 110 in the period from time td to time te does not satisfy the accumulation condition for discharge.

[0168] In another embodiment, Std is set so that the ratio of the absolute value of the difference between Sd and Std to Sd (i.e., (Sd-Std) / Sd) is a predetermined value (sometimes referred to as the second discharge threshold). According to this embodiment, the ratio of Vde to Sd is smaller than the second discharge threshold. At this time, the management server 102 may determine that the degree of fluctuation in the SOC of the storage module 110 does not satisfy the accumulation condition for discharge during the period from time td to time te.

[0169] (time te~time tf) Thereafter, the SOC of the power storage module 110 also increases as the power storage module 110 is charged. According to this embodiment, when the SOC of the power storage module 110 reaches Sf [%] at time tf, the charging of the power storage module 110 ends and the discharging of the power storage module 110 starts.

[0170] (time tf~time tg) According to this embodiment, after the discharge of the power storage module 110 starts at time tf, the power storage module 110 is repeatedly discharged and charged, and as a result, the SOC of the power storage module 110 becomes smaller than Stf [%] at time tg. During part of the period from time tf to time tg, no fluctuation in the SOC may be observed. In other embodiments, the SOC of the power storage module 110 may monotonically decrease during the period from time tf to time tg.

[0171] According to this embodiment, in the period from time tf to time tg, the SOC of the power storage module 110 is equal to or smaller than Sf, and in the period from time tf to time tg, the SOC of the power storage module 110 is greater than or equal to Stf.

[0172] In one embodiment, Stf is set so that the absolute value of the difference between Sf and Stf is a predetermined value (sometimes referred to as a third discharge threshold). According to this embodiment, after the discharge of the power storage module 110 starts at time tf, the absolute value of the difference between the SOC of the power storage module 110 and Sf (sometimes referred to as a discharge amount) becomes greater than the third discharge threshold before the SOC of the power storage module 110 becomes greater than Sf.

[0173] At this time, the management server 102 may determine that the degree of fluctuation in the SOC of the power storage module 110 during the period from time tf to time tg satisfies the above-described integration condition. The management server 102 may determine that the degree of fluctuation in the SOC of the power storage module 110 during the period from time tf to time tg satisfies the integration condition related to discharging.

[0174] In another embodiment, Stf is set so that the ratio of the absolute value of the difference between Sf and Stf to Sf (i.e., (Sf-Stf) / Sf) is a predetermined value (sometimes referred to as a fourth discharge threshold). According to this embodiment, after discharging of the power storage module 110 starts at time tf, the ratio of the absolute value of the difference between Sf and Stf to Sf becomes greater than the fourth charge threshold before the SOC of the power storage module 110 becomes greater than Sf.

[0175] At this time, the management server 102 may determine that the degree of fluctuation in the SOC of the power storage module 110 during the period from time tf to time tg satisfies the above-described integration condition. The management server 102 may determine that the degree of fluctuation in the SOC of the power storage module 110 during the period from time tf to time tg satisfies the integration condition related to discharging.

[0176] According to this embodiment, the integration condition for charging is satisfied in the period from time tb to time tf, and the integration condition for discharging is satisfied in the period from time tf to time tg. Therefore, for example, at time tg, the management server 102 determines that the charge / discharge state of the power storage module 110 at time tf has switched from a charging tendency to a discharging tendency.

[0177] At time tg, the management server 102 may decide to update the reference time point. Specifically, the management server 102 sets time tf as a new reference time point. The management server 102 may set time tf as a reference time point for discharging the power storage module 110. In addition, Sf, which is the SOC of the power storage module 110 at time tf, is set as a reference value.

[0178] (time tg~time th) Thereafter, the SOC of the power storage module 110 also decreases as the power storage module 110 discharges. According to this embodiment, at time th, the SOC of the power storage module 110 becomes smaller than Sa.

[0179] As described above, according to this embodiment, after charging of the power storage module 110 starts at time tb, the SOC of the power storage module 110 increases from Sa to Sf while repeatedly slightly increasing and decreasing. Thereafter, the SOC of the power storage module 110 decreases from Sf to Sa while repeatedly slightly increasing and decreasing. Sf, which is the SOC of the power storage module 110 at time tf, may be the maximum value of the SOC of the power storage module 110 during the period from time tb to time th.

[0180] In this embodiment, the management server 102 detects that the SOC of the power storage module 110 has changed from Sa to Sf in the period from time tb to time th. The management server 102 derives a stress index value for the period from time tb to time th based on the detected amount of change in SOC and the above-mentioned correspondence information. As a result, a stress index value for the charging period (i.e., the period from time tb to time tf) in the period from time tb to time th is derived.

[0181] For example, the management server 102 accumulates one or more stress index values ​​and manages the degree of deterioration, remaining life span, or replacement time of the power storage module 110 based on the accumulated value. The management server 102 may derive the accumulated value of the stress index values ​​every time a new stress index value is derived, or may derive the accumulated value of one or more stress index values ​​derived within an arbitrary period.

[0182] Time tb in FIG. 6 may be an example of a reference time point for charging the power storage module 110. Sa in FIG. 6 may be an example of a reference value for charging the power storage module 110. Time tc in FIG. 6 may be an example of a second charging time point. Time td in FIG. 6 may be an example of a third charging time point. Time tf in FIG. 6 may be an example of a fourth charging time point. Time tf in FIG. 6 may be an example of a reference time point for discharging the power storage module 110. Sf in FIG. 6 may be an example of a reference value for discharging the power storage module 110.

[0183] Time td in Fig. 6 may be an example of a reference time point regarding the discharge of the power storage module 110. Sd in Fig. 6 may be an example of a reference value regarding the discharge of the power storage module 110. Time te in Fig. 6 may be an example of a first discharge time point. The period from time td to time te in Fig. 6 may be an example of a second period. Vde in Fig. 6 may be an example of a second fluctuation amount.

[0184] (An example of another embodiment) In the present embodiment, an example of the determination process by the management server 102 has been described using as an example a case where the reference time point that is set first after the power storage system 104 is turned on is time tb. However, the determination process by the management server 102 is not limited to this embodiment. In other embodiments, the time ta may be set as the reference time point that is set first after the power storage system 104 is turned on.

[0185] In the present embodiment, an example of the process of determining whether the accumulation condition is met by the management server 102 has been described, taking as an example a case in which the reference time point is updated when the charge / discharge state of the power storage module 110 shifts from a charging tendency to a discharging tendency. However, the determination process by the management server 102 is not limited to this embodiment. In other embodiments, the reference time point may be updated when it is determined that the degree of variation in the SOC of the power storage module 110 satisfies the accumulation condition. For example, time tc, time td, or time te may be set as a new reference time point.

[0186] The management server 102 may detect a fluctuation in the SOC of the power storage module 110 each time the reference time point is updated. The management server 102 may derive an amount of fluctuation in the SOC of the power storage module 110 each time the reference time point is updated. The management server 102 may derive a stress index value each time the reference time point is updated.

[0187] Fig. 7 is a schematic diagram showing another example of the determination process for the power storage module 110 having a charging tendency. In Fig. 7, a solid line 720 indicates the fluctuation history of the SOC of the power storage module 110. An example of the determination process during the charging period of the power storage module 110 will be described with reference to Fig. 7. Specifically, an example of the determination process by the management server 102 will be described by taking as an example a case where the management server 102 determines that the degree of fluctuation in the SOC of the power storage module 110 does not satisfy the above-mentioned integration condition.

[0188] In this embodiment, an example of the determination process by the management server 102 will be described using as an example a case where charging of the power storage module 110 is started at the above-mentioned reference time point, or a case where the power storage module 110 is being charged at the reference time point. Note that the determination process for the power storage module 120 tending to be charged can be executed by a procedure similar to that of the determination process for the power storage module 110 tending to be charged.

[0189] (time ta~time tb) According to this embodiment, first, at time ta, the power storage system 104 is powered on. At this time, the SOC of the power storage module 110 arranged in the power storage system 104 is Sa [%]. Then, at time tb, charging of the power storage module 110 starts.

[0190] In this embodiment, the management server 102 sets the time tb as the reference time point that is set first after the power storage system 104 is turned on. The management server 102 may set the time tb as the reference time point for charging the power storage module 110. In addition, Sa, which is the SOC of the power storage module 110 at the time tb, is set as a reference value.

[0191] (time tb ~ time ti) After charging of the power storage module 110 starts at time tb, for example, charging and discharging of the power storage module 110 are repeated. According to this embodiment, the SOC of the power storage module 110 reaches a maximum value Sj [%] in the period from time tb to time ti at time tj, and then becomes smaller than Sa at time ti. During part of the period from time tb to time ti, no fluctuation in the SOC may be observed.

[0192] According to this embodiment, in the period from time tb to time ti, the SOC of the power storage module 110 is greater than or equal to Sa. Also, in the period from time tb to time ti, the SOC of the power storage module 110 is less than Sta [%].

[0193] In one embodiment, Sta is set so that the absolute value of the difference between Sta and Sa, which is a reference value during the period from time tb to time ti, is a predetermined value (sometimes referred to as a first charging threshold). According to this embodiment, the absolute value Vbi of the difference between Sa and Sj, which is the maximum SOC of the power storage module 110 during the period from time tb to time ti, is smaller than the first charging threshold. The first charging threshold may be the same as the third charging threshold, or may be smaller than the third charging threshold, or may be larger than the third charging threshold.

[0194] At this time, the management server 102 may determine that the degree of fluctuation in the SOC of the power storage module 110 does not satisfy the above-mentioned integration condition during the period from time tb to time ti. The management server 102 may determine that the degree of fluctuation in the SOC of the power storage module 110 does not satisfy the integration condition related to charging during the period from time tb to time ti.

[0195] In another embodiment, Sta is set so that the ratio of the absolute value of the difference between Sa and Sta to the above-mentioned reference value Sa (i.e., (Sta-Sa) / Sa) is a predetermined value (sometimes referred to as the second charging threshold). According to this embodiment, the ratio of the above-mentioned Vbi to the reference value Sa is smaller than the second charging threshold. The second charging threshold may be the same as the fourth charging threshold, or may be smaller than the fourth charging threshold, or may be greater than the fourth charging threshold.

[0196] At this time, the management server 102 may determine that the degree of fluctuation in the SOC of the power storage module 110 does not satisfy the above-mentioned integration condition during the period from time tb to time ti. The management server 102 may determine that the degree of fluctuation in the SOC of the power storage module 110 does not satisfy the integration condition related to charging during the period from time tb to time ti.

[0197] Time ti in Fig. 7 may be an example of a first charging point in time. The period from time tb to time ti in Fig. 7 may be an example of a first period. Vbi in Fig. 7 may be an example of a first fluctuation amount.

[0198] 8 illustrates an example of the internal configuration of the management server 102. In this embodiment, the management server 102 includes, for example, a storage unit 820, a corresponding information acquisition unit 830, and a data collection unit 840. The management server 102 includes, for example, a fluctuation detection unit 852, a determination unit 854, an index derivation unit 856, and an integrated value derivation unit 858. The management server 102 includes, for example, a cycle number estimation unit 860, a SOH derivation unit 874, and a replacement time estimation unit 876.

[0199] In this embodiment, the storage unit 820 stores various types of information. In one embodiment, the storage unit 820 stores various types of information used for information processing in the management server 102. The storage unit 820 stores, for example, the above-mentioned correspondence information. The storage unit 820 may store the above-mentioned correspondence information for each power storage module or for each type of power storage module. In another embodiment, the storage unit 820 stores various types of information generated by information processing in the management server 102.

[0200] In this embodiment, the correspondence information acquisition unit 830 acquires the above-mentioned correspondence information. The correspondence information acquisition unit 830 may output the correspondence information to the index derivation unit 856. In one embodiment, the correspondence information acquisition unit 830 acquires the correspondence information stored in the storage unit 820. In another embodiment, the correspondence information acquisition unit 830 generates the above-mentioned correspondence information. The correspondence information acquisition unit 830 may store the generated correspondence information in the storage unit 820. This allows the correspondence information acquisition unit 830 to acquire the correspondence information. Details of the procedure for generating the correspondence information will be described later.

[0201] In this embodiment, the data collection unit 840 collects various types of data. The data collection unit 840 may execute at least a part of the information processing in S322 described in relation to FIG.

[0202] In one embodiment, the data collection unit 840 collects information on the specifications of each power storage module. The data collection unit 840 may access an information processing device managed or operated by a manufacturer or the like of each power storage module to collect information on the specifications of each power storage module. Examples of the information on the specifications of each power storage module include the full charge capacity in the initial state of each power storage module, the above-mentioned information on the specifications of the power storage unit included in each power storage module, or similar information. In another embodiment, the data collection unit 840 acquires information indicating the SOC of each power storage module. The data collection unit 840 may acquire information indicating the SOC of each power storage module from the power storage system 104.

[0203] The data collection section 840 may store the collected information in the storage section 820. The data collection section 840 may output, to the fluctuation detection section 852, information indicating the SOC of each power storage module.

[0204] In this embodiment, the fluctuation detection unit 852 detects fluctuations in the SOC of each power storage module. The fluctuation detection unit 852 may execute at least a part of the information processing in S322 described in relation to FIG.

[0205] The fluctuation detection unit 852 detects fluctuations in the SOC of each of the power storage modules 110 and 120 based on, for example, information acquired by the data collection unit 840 from the power storage system 104. The fluctuation detection unit 852 may detect fluctuations in the SOC of each power storage module based on a value (sometimes referred to as a reference value) of the SOC of each power storage module at a specific point in time (sometimes referred to as a reference point in time).

[0206] In the present embodiment, the determination unit 854 determines whether the degree of fluctuation in the SOC of each power storage module satisfies the above-described integration condition. The determination unit 854 may execute at least a part of the information processing in S324 described in relation to Fig. 3. The determination unit 854 may determine whether the degree of fluctuation in the SOC of each power storage module satisfies the above-described integration condition in accordance with the procedures described in relation to Figs. 4 to 7.

[0207] In one embodiment, the determination unit 854 outputs information indicating the determination result to, for example, the index derivation unit 856. In another embodiment, the determination unit 854 may output information indicating the determination result to the integrated value derivation unit 858.

[0208] (Discharge judgment process) (a) When discharging of the power storage module 110 starts at the reference time point, or when the power storage module 110 is discharging at the reference time point, the determination unit 854 determines whether or not the degree of fluctuation in the SOC of the power storage module 110 satisfies the integration condition, for example, according to the following procedure. The determination unit 854 may determine whether or not the degree of fluctuation in the SOC of the power storage module 110 satisfies the integration condition for each of one or more periods. Note that the determination unit 854 may also determine whether or not the degree of fluctuation in the SOC of the power storage module 120 satisfies the integration condition, according to a similar procedure.

[0209] (Examples of cases where it is determined that the accumulation conditions are not met) For example, at least (i) when a first fluctuation amount, which is the absolute value of the difference between the minimum value of the SOC of the power storage module 110 and the reference value during a period (may be referred to as a first period) from the reference time point to the time point (may be referred to as a first discharge time point) when the SOC of the power storage module 110 becomes greater than the reference value, is smaller than a predetermined value (may be referred to as a first discharge threshold), or (ii) when the ratio of the first fluctuation amount to the reference value is smaller than a predetermined value (may be referred to as a second discharge threshold), the determining unit 854 determines that the degree of fluctuation in the SOC of the power storage module 110 during the first period does not satisfy the integration condition. The first discharge time point may be a time point later than the reference time point.

[0210] (Examples of cases where it is determined that the accumulation conditions are met) For example, at least when (iii) the discharge amount, which is the absolute value of the difference between the SOC of the power storage module 110 and the reference value, becomes greater than a predetermined value (sometimes referred to as a third discharge threshold) before the SOC of the power storage module 110 becomes greater than the reference value, or when (iv) the ratio of the discharge amount to the reference value becomes greater than a predetermined value (sometimes referred to as a fourth discharge threshold) before the SOC of the power storage module 110 becomes greater than the reference value, the determination unit 854 determines that the degree of fluctuation in the SOC of the power storage module 110 satisfies the integration condition. The third discharge threshold may be the same as the first discharge threshold or may be greater than the first discharge threshold. The fourth discharge threshold may be the same as the second discharge threshold or may be greater than the second discharge threshold.

[0211] (Reference update process during discharge) In this embodiment, the determination unit 854 updates the reference time point at an appropriate timing. At this time, the reference value is also updated with the update of the reference time point. For example, the determination unit 854 updates the reference time point when it is determined that the degree of SOC fluctuation satisfies the integration condition. Examples of the reference time point after the update include (i) a second discharge time point, which is a time point when the discharge amount becomes larger than a third discharge threshold or a time point when the ratio of the discharge amount to the reference value becomes larger than a fourth discharge threshold, (ii) a third discharge time point, which is the earliest time point when charging of the storage module 110 starts after the second discharge time point, or (iii) a fourth discharge time point, which is a time point when the charge / discharge state of the storage module 110 changes from a discharging tendency to a charging tendency after the third discharge time point.

[0212] (Determination process during charging) (b) When charging of the power storage module 110 is started at the reference time point, or when the power storage module 110 is being charged at the reference time point, the determination unit 854 determines whether or not the degree of fluctuation in the SOC of the power storage module 110 satisfies the integration condition, for example, according to the following procedure. The determination unit 854 may determine whether or not the degree of fluctuation in the SOC of the power storage module 110 satisfies the integration condition for each of one or more periods. Note that the determination unit 854 may also determine whether or not the degree of fluctuation in the SOC of the power storage module 120 satisfies the integration condition, according to a similar procedure.

[0213] (Examples of cases where it is determined that the accumulation conditions are not met) For example, at least (i) when a second fluctuation amount, which is the absolute value of the difference between the maximum SOC value of the power storage module 110 and the reference value during a period (sometimes referred to as a second period) from the reference time point to the time point (sometimes referred to as a first charging time point) when the SOC of the power storage module 110 becomes smaller than the reference value, is smaller than a predetermined value (sometimes referred to as a first charging threshold), or (ii) when the ratio of the second fluctuation amount to the reference value is smaller than a predetermined value (sometimes referred to as a second charging threshold). The first charging time point may be a time point later than the reference time point.

[0214] (Examples of cases where it is determined that the accumulation conditions are met) For example, at least when (iii) the charge amount, which is the absolute value of the difference between the SOC of the power storage module 110 and the reference value, becomes greater than a predetermined value (sometimes referred to as a third charge threshold) before the SOC of the power storage module 110 becomes smaller than the reference value, or when (iv) the ratio of the discharge amount to the reference value becomes greater than a predetermined value (sometimes referred to as a fourth charge threshold) before the SOC of the power storage module 110 becomes smaller than the reference value, the determination unit 854 determines that the degree of fluctuation in the SOC of the power storage module 110 satisfies the integration condition. The third charge threshold may be the same as the first charge threshold or may be greater than the first charge threshold. The fourth charge threshold may be the same as the second charge threshold or may be greater than the second charge threshold.

[0215] (Reference update process during charging) In this embodiment, the determination unit 854 updates the reference time point at an appropriate timing. At this time, the reference value is also updated with the update of the reference time point. For example, the determination unit 854 updates the reference time point when it is determined that the degree of SOC fluctuation satisfies the integration condition. Examples of the reference time point after the update include (i) a second charging time point that is a time point when the charge amount becomes larger than a third charging threshold or a time point when the ratio of the charge amount to the reference value becomes larger than a fourth charging threshold, (ii) a third discharging time point that is the earliest time point when the discharge of the storage module 110 starts after the second charging time point, or (iii) a fourth charging time point that is a time point when the charge / discharge state of the storage module 110 changes from a charging tendency to a discharging tendency after the third discharging time point.

[0216] In this embodiment, the index derivation unit 856 derives the above-mentioned stress index value. The index derivation unit 856 may execute at least a part of the information processing in S326 described in relation to Fig. 3. The index derivation unit 856 may derive the above-mentioned stress index value according to the procedures described in relation to Figs. 4 to 7.

[0217] In one embodiment, the index derivation unit 856 derives a stress index value when the degree of SOC variation satisfies the integration condition, and does not derive a stress index value when the degree of SOC variation does not satisfy the integration condition. In another embodiment, the index derivation unit 856 derives a stress index value regardless of whether the degree of SOC variation satisfies the integration condition.

[0218] (Indicator derivation process during discharge) In this embodiment, the index derivation unit 856 derives the stress index value based on, for example, the absolute value of the difference between the SOC of the power storage module at the second discharge time point described above and a reference value at that time point. The index derivation unit 856 may derive the stress index value based on the absolute value of the difference between the SOC of the power storage module and the reference value (which may be referred to as the discharge amount as described above) and the correspondence relationship described above.

[0219] In this embodiment, the index derivation unit 856 derives the stress index value based on, for example, the absolute value of the difference between the SOC of the power storage module at the third discharge time point described above and a reference value at that time point. The index derivation unit 856 may derive the stress index value based on the absolute value of the difference between the SOC of the power storage module and the reference value (which may be referred to as the discharge amount as described above) and the correspondence relationship described above.

[0220] In this embodiment, the index derivation unit 856 derives the stress index value based on, for example, the absolute value of the difference between the SOC of the power storage module at the fourth discharge time point described above and a reference value at that time point. The index derivation unit 856 may derive the stress index value based on the absolute value of the difference between the SOC of the power storage module and the reference value (which may be referred to as the discharge amount as described above) and the correspondence relationship described above.

[0221] In one embodiment, the index derivation unit 856 inputs the discharge amount in the specific period as an explanatory variable into a function indicating the above-mentioned correspondence information. The above-mentioned function outputs a stress index value. As a result, the stress index value in the above-mentioned specific period is obtained. In another embodiment, the index derivation unit 856 refers to a table indicating the above-mentioned correspondence information to obtain a stress index value corresponding to the discharge amount in the specific period. As a result, the stress index value in the above-mentioned specific period is obtained.

[0222] In the embodiment described in relation to Fig. 4, the discharge amount in the specific period may be the discharge amount from time tb to time tc. The discharge amount may be the discharge amount from time tb to time td, or may be the discharge amount from time tb to time tf.

[0223] (Indicator derivation process during charging) In this embodiment, the index derivation unit 856 derives the stress index value based on, for example, the absolute value of the difference between the SOC of the power storage module at the second charging point described above and a reference value at that point in time. The index derivation unit 856 may derive the stress index value based on the absolute value of the difference between the SOC of the power storage module and the reference value (which may be referred to as the charge amount as described above) and the correspondence relationship described above.

[0224] In this embodiment, the index derivation unit 856 derives the stress index value based on, for example, the absolute value of the difference between the SOC of the power storage module at the third charging time point described above and a reference value at that time point. The index derivation unit 856 may derive the stress index value based on the absolute value of the difference between the SOC of the power storage module and the reference value (which may be referred to as the charge amount as described above) and the correspondence relationship described above.

[0225] In this embodiment, the index derivation unit 856 derives the stress index value based on, for example, the absolute value of the difference between the SOC of the power storage module at the fourth charging time point described above and a reference value at that time point. The index derivation unit 856 may derive the stress index value based on the absolute value of the difference between the SOC of the power storage module and the reference value (which may be referred to as the charge amount as described above) and the correspondence relationship described above.

[0226] In one embodiment, the index derivation unit 856 inputs the charge amount in the specific period as an explanatory variable into a function indicating the above-mentioned correspondence information. The above-mentioned function outputs a stress index value. As a result, the stress index value in the above-mentioned specific period is obtained. In another embodiment, the index derivation unit 856 refers to a table indicating the above-mentioned correspondence information to obtain a stress index value corresponding to the charge amount in the specific period. As a result, the stress index value in the above-mentioned specific period is obtained.

[0227] 6, the charge amount in a specific period may be the charge amount from time tb to time tc. The discharge amount may be the discharge amount from time tb to time td, or may be the charge amount from time tb to time tf.

[0228] In this embodiment, the integrated value derivation unit 858 derives the integrated value of the above-mentioned stress index value. The integrated value derivation unit 858 may execute at least a part of the information processing in S328 described in relation to Fig. 3. The integrated value derivation unit 858 may derive the above-mentioned stress index value according to the procedures described in relation to Figs. 4 to 7.

[0229] In this embodiment, the integrated value derivation unit 858 derives an integrated value of the stress index value in either the period during which the power storage module is charged (sometimes referred to as a charging period) or the period during which the power storage module is discharged (sometimes referred to as a discharging period) based on the stress index value when the degree of variation in the SOC of the power storage module satisfies the above-mentioned integration condition. The integrated value derivation unit 858 may exclude from the above-mentioned integration process the stress index value when the degree of variation in the SOC of the power storage module does not satisfy the above-mentioned integration condition.

[0230] In one embodiment, the integrated value derivation unit 858 integrates the stress index value in each of one or more periods during which the degree of fluctuation in the SOC of the power storage module satisfies the above-described integration condition among multiple periods during which the power storage module is discharged. In another embodiment, the integrated value derivation unit 858 integrates the stress index value in each of one or more periods during which the degree of fluctuation in the SOC of the power storage module satisfies the above-described integration condition among multiple periods during which the power storage module is charged.

[0231] In this embodiment, the cycle number estimation unit 860 estimates the current cycle number of each power storage module. The cycle number estimation unit 860 may execute at least a part of the information processing in S330 described in relation to FIG. 3. The process of estimating the cycle number of the power storage module may be part of a process of estimating the replacement time or lifespan of the power storage module. The replacement time or lifespan of the power storage module may be an example of an index indicating the degree of deterioration of the power storage module.

[0232] In this embodiment, the cycle number estimation unit 860 estimates the current cycle number of each power storage module based on the integrated value of the stress index value of each power storage module output by the integrated value derivation unit 858. Specifically, the cycle number estimation unit 860 determines how many cycles the integrated value of the stress index value of each power storage module output by the integrated value derivation unit 858 corresponds to, assuming that one cycle is full charge and full discharge. As described above, when the integrated value of the stress index value corresponding to the fluctuation in the SOC of the power storage module in a specific period is N (N is a positive number), the current cycle number of each power storage module is N, assuming that one cycle is full charge and full discharge.

[0233] In this embodiment, the SOH derivation unit 874 derives the SOH of each power storage module. The SOH derivation unit 874 may execute at least a part of the information processing at S330 described in relation to FIG. 3. The process of deriving the SOH of the power storage module may be part of a process of estimating the replacement time or lifespan of the power storage module. The replacement time or lifespan of the power storage module may be an example of an index indicating the degree of deterioration of the power storage module.

[0234] The SOH derivation unit 874 derives the SOH of each power storage module, for example, by dividing the current full charge capacity of each power storage module by the full charge capacity in the initial state of each power storage module collected by the data collection unit 840. The full charge capacity in the initial state of the power storage module may be a value presented by the manufacturer or the like of the power storage module, or may be a value estimated by the management server 102 at the time when management by the management server 102 is started.

[0235] In this embodiment, the replacement time estimation unit 876 estimates the replacement time of each power storage module. In one embodiment, the replacement time estimation unit 876 estimates the replacement time of each power storage module based on the SOH of each power storage module derived by the SOH derivation unit 874. In another embodiment, the replacement time estimation unit 876 estimates the replacement time of each power storage module based on the current cycle number of each power storage module estimated by the cycle number estimation unit 860.

[0236] In this embodiment, the replacement time estimation unit 876 estimates the replacement time of each power storage module, for example, according to the procedure described in relation to S330 in Fig. 3. The replacement time of the power storage module may be an example of an index indicating the degree of deterioration or lifespan of the power storage module.

[0237] The replacement time estimation unit 876 may manage the performance of each storage module, or may manage the quality variation between storage module model numbers, or may manage the quality variation between manufacturers, etc., based on (i) information indicating the relationship between the SOH and cycle number of each storage module provided by the manufacturer or the like of each storage module, and (ii) information indicating the relationship between the SOH of each storage module derived by the SOH derivation unit 874 and the current cycle number of each storage module estimated by the cycle number estimation unit 860.

[0238] (Specific configuration of each part of the management server 102) Each part of the management server 102 may be realized by hardware, software, or hardware and software. Each part of the management server 102 may be realized, at least in part, by a single server or by multiple servers. Each part of the management server 102 may be realized, at least in part, on a virtual machine or a cloud system. Each part of the management server 102 may be realized, at least in part, by a personal computer or a mobile terminal. Examples of the mobile terminal include a mobile phone, a smartphone, a PDA (registered trademark), a tablet, a notebook computer or laptop computer, and a wearable computer. Each part of the management server 102 may store information using a distributed ledger technology such as a blockchain or a distributed network.

[0239] When at least a part of the components constituting the management server 102 is realized by software, the components realized by the software may be realized by starting software or a program that defines the operation of the components in an information processing device with a general configuration. The information processing device with the general configuration described above may include (i) a data processing device having a processor such as a CPU or GPU, a ROM, a RAM, a communication interface, etc., (ii) input devices such as a keyboard, a pointing device, a touch panel, a camera, a voice input device, a gesture input device, various sensors, a GPS receiver, etc., (iii) output devices such as a display device, a voice output device, a vibration device, etc., and (iv) storage devices such as a memory, an HDD, an SSD, etc. (including an external storage device).

[0240] In the information processing device of the above general configuration, the above data processing device or storage device may store the above software or program. The above software or program, when executed by a processor, causes the above information processing device to execute the operation defined by the software or program. The above software or program may be stored in a non-transitory computer-readable recording medium. The above software or program may be a program for causing a computer to function as the management server 102 or a part thereof. The above software or program may be a program for causing a computer to execute an information processing method in the management server 102 or a part thereof.

[0241] In this embodiment, the information processing method includes, for example, a fluctuation detection step of detecting a fluctuation in the state of charge of the storage battery. The information processing method includes, for example, an index value derivation step of deriving a stress index value, which is an index indicating a ratio of a degree of stress given to the storage battery by the fluctuation detected in the fluctuation detection step to a degree of stress given to the storage battery by charging and discharging when the storage battery is charged and discharged with full charging and full discharging being one cycle. The information processing method includes, for example, an integrated value derivation step of deriving an integrated value of the stress index value in either a charging period during which the storage battery is charged or a discharging period during which the storage battery is discharged, based on a stress index value when the degree of the fluctuation satisfies a predetermined condition.

[0242] The storage unit 820 may be an example of a storage device. The management server 102 may be an example of a computer. The CPU, GPU, and / or processor included in the management server 102 may be an example of a computer.

[0243] Fig. 9 is a schematic diagram showing an example of a process for generating correspondence information. An example of information processing in the correspondence information acquisition unit 830 will be described with reference to Fig. 9, taking as an example a case where the correspondence information acquisition unit 830 generates the correspondence information of the power storage module 110, and thereby the correspondence information acquisition unit 830 acquires the correspondence information of the power storage module 110.

[0244] In this embodiment, the correspondence information acquisition unit 830 acquires, for example, information 922 indicating the correspondence relationship between the depth of discharge of the power storage module 110 and the cycle life of the power storage module 110. The correspondence information acquisition unit 830 may acquire the above information 922 by accessing an information processing device managed or operated by a manufacturer or the like of the power storage module 110.

[0245] In this embodiment, the correspondence information acquisition unit 830 generates information 924 indicating a correspondence relationship between the charge / discharge depth of the power storage module 110 and the stress index value of the power storage module 110 based on the above information 922. Specifically, first, the correspondence information acquisition unit 830 determines a cycle life at a specific discharge depth as a reference cycle life. For example, the correspondence information acquisition unit 830 determines a cycle life when the discharge depth is 85% as the reference cycle life. The reference cycle life may be a value designated by the manufacturer of the power storage module 110, etc.

[0246] Next, the corresponding information acquisition unit 830 determines a stress index value corresponding to each of the one or more depths of discharge by dividing the reference cycle life by the value of the cycle life at each of the one or more depths of discharge. In this way, the corresponding information acquisition unit 830 generates the above-mentioned information 924.

[0247] 10 illustrates an example of a computer 3000 in which aspects of the present invention may be embodied in whole or in part. At least a portion of the power system 100 may be realized by one or more computers 3000. For example, at least a portion of the management server 102 is realized by one or more computers 3000. For example, at least a portion of the power storage system 104 is realized by one or more computers 3000.

[0248] A program installed on the computer 3000 may cause the computer 3000 to function as or perform operations associated with an apparatus according to an embodiment of the present invention or one or more "parts" of the apparatus, and / or to perform a process or steps of the process according to an embodiment of the present invention. Such a program may be executed by the CPU 3012 to cause the computer 3000 to perform certain operations associated with some or all of the blocks of the flowcharts and block diagrams described herein.

[0249] The computer 3000 according to this embodiment includes a CPU 3012, a RAM 3014, a graphic controller 3016, and a display device 3018, which are connected to each other by a host controller 3010. The computer 3000 also includes input / output units such as a communication interface 3022, a hard disk drive 3024, a DVD-ROM drive 3026, and an IC card drive, which are connected to the host controller 3010 via an input / output controller 3020. The computer also includes legacy input / output units such as a ROM 3030 and a keyboard 3042, which are connected to the input / output controller 3020 via an input / output chip 3040.

[0250] The CPU 3012 operates according to a program stored in the ROM 3030 and the RAM 3014, thereby controlling each unit. The graphic controller 3016 acquires image data generated by the CPU 3012 into a frame buffer or the like provided in the RAM 3014 or into itself, and causes the image data to be displayed on the display device 3018.

[0251] The communications interface 3022 communicates with other electronic devices via a network. The hard disk drive 3024 stores programs and data used by the CPU 3012 in the computer 3000. The DVD-ROM drive 3026 reads programs or data from the DVD-ROM 3001 and provides the programs or data to the hard disk drive 3024 via the RAM 3014. The IC card drive reads programs and data from an IC card and / or writes programs and data to an IC card.

[0252] The ROM 3030 stores therein a boot program or the like executed by the computer 3000 upon activation, and / or a program that depends on the hardware of the computer 3000. The input / output chip 3040 may also connect various input / output units to the input / output controller 3020 via a parallel port, a serial port, a keyboard port, a mouse port, etc.

[0253] The programs are provided by a computer-readable storage medium such as a DVD-ROM 3001 or an IC card. The programs are read from the computer-readable storage medium, installed in the hard disk drive 3024, the RAM 3014, or the ROM 3030, which are also examples of computer-readable storage media, and executed by the CPU 3012. Information processing described in these programs is read by the computer 3000, and brings about cooperation between the programs and the various types of hardware resources described above. An apparatus or method may be constructed by realizing an operation or processing of information according to the use of the computer 3000.

[0254] For example, when communication is performed between computer 3000 and an external device, CPU 3012 may execute a communication program loaded in RAM 3014 and instruct communication interface 3022 to perform communication processing based on the processing described in the communication program. Under the control of CPU 3012, communication interface 3022 reads transmission data stored in a transmission buffer area provided in RAM 3014, hard disk drive 3024, DVD-ROM 3001, or a recording medium such as an IC card, and transmits the read transmission data to the network, or writes reception data received from the network to a reception buffer area or the like provided on the recording medium.

[0255] Furthermore, CPU 3012 may cause all or a necessary portion of a file or database stored in an external recording medium such as hard disk drive 3024, DVD-ROM drive 3026 (DVD-ROM 3001), an IC card, etc. to be read into RAM 3014, and perform various types of processing on the data on RAM 3014. CPU 3012 may then write back the processed data to the external recording medium.

[0256] Various types of information, such as various types of programs, data, tables, and databases, may be stored in the recording medium and undergo information processing. The CPU 3012 may perform various types of processing on the data read from the RAM 3014, including various types of operations, information processing, conditional judgment, conditional branching, unconditional branching, information search / replacement, etc., as described throughout this disclosure and specified by the instruction sequence of the program, and writes back the results to the RAM 3014. The CPU 3012 may also search for information in a file, database, etc. in the recording medium. For example, when a plurality of entries each having an attribute value of a first attribute associated with an attribute value of a second attribute are stored in the recording medium, the CPU 3012 may search for an entry whose attribute value of the first attribute matches a specified condition from among the plurality of entries, read the attribute value of the second attribute stored in the entry, and thereby obtain the attribute value of the second attribute associated with the first attribute that satisfies a predetermined condition.

[0257] The above-described programs or software modules may be stored in a computer-readable storage medium on the computer 3000 or in the vicinity of the computer 3000. In addition, a recording medium such as a hard disk or a RAM provided in a server system connected to a dedicated communication network or the Internet can be used as a computer-readable storage medium, thereby providing the above-described programs to the computer 3000 via the network.

[0258] The blocks in the flowcharts and block diagrams in the above embodiments may represent stages of a process in which an operation is performed or "parts" of an apparatus responsible for performing the operation. Particular stages and "parts" may be implemented by dedicated circuitry, programmable circuitry provided with computer readable instructions stored on a computer readable storage medium, and / or a processor provided with computer readable instructions stored on a computer readable storage medium. The dedicated circuitry may include digital and / or analog hardware circuits, and may include integrated circuits (ICs) and / or discrete circuits. The programmable circuitry may include reconfigurable hardware circuits, such as, for example, field programmable gate arrays (FPGAs), programmable logic arrays (PLAs), and the like, including AND, OR, XOR, NAND, NOR, and other logical operations, flip-flops, registers, and memory elements.

[0259] A computer-readable storage medium may include any tangible device capable of storing instructions that are executed by a suitable device, such that a computer-readable storage medium having instructions stored thereon comprises an article of manufacture that includes instructions that can be executed to create means for performing the operations specified in the flowcharts or block diagrams. Examples of computer-readable storage media may include electronic storage media, magnetic storage media, optical storage media, electromagnetic storage media, semiconductor storage media, and the like. More specific examples of computer-readable storage media may include floppy disks, diskettes, hard disks, random access memories (RAMs), read-only memories (ROMs), erasable programmable read-only memories (EPROMs or flash memories), electrically erasable programmable read-only memories (EEPROMs), static random access memories (SRAMs), compact disk read-only memories (CD-ROMs), digital versatile disks (DVDs), Blu-ray disks, memory sticks, integrated circuit cards, and the like.

[0260] The computer readable instructions may include either assembler instructions, instruction set architecture (ISA) instructions, machine instructions, machine-dependent instructions, microcode, firmware instructions, state setting data, or source or object code written in any combination of one or more programming languages, including object-oriented programming languages ​​such as Smalltalk®, JAVA®, C++, etc., and conventional procedural programming languages ​​such as the “C” programming language or similar programming languages.

[0261] Computer readable instructions may be provided to a processor of a general purpose computer, special purpose computer, or other programmable data processing apparatus, or to a programmable circuit, either locally or over a local area network (LAN), a wide area network (WAN), such as the Internet, etc., to cause the processor of the general purpose computer, special purpose computer, or other programmable data processing apparatus, or to a programmable circuit, to execute the computer readable instructions to generate means for performing the operations specified in the flowcharts or block diagrams. Examples of processors include computer processors, processing units, microprocessors, digital signal processors, controllers, microcontrollers, etc.

[0262] Although the present invention has been described above using the embodiments, the technical scope of the present invention is not limited to the scope described in the above embodiments. It is clear to those skilled in the art that various modifications or improvements can be made to the above embodiments. Furthermore, the matters described for a specific embodiment can be applied to other embodiments to the extent that they are not technically inconsistent. Furthermore, each component may have the same features as other components having the same name and different reference numerals. It is clear from the claims that such modified or improved forms may also be included in the technical scope of the present invention.

[0263] It should be noted that the order of execution of each process, such as operations, procedures, steps, and stages, in the devices, systems, programs, and methods shown in the claims, specifications, and drawings is not specifically stated as "before," "prior to," etc., and may be realized in any order unless the output of a previous process is used in a later process. Even if the operational flow in the claims, specifications, and drawings is explained using "first," "next," etc. for convenience, it does not mean that it is essential to perform the process in this order. [Explanation of symbols]

[0264] 10 communication network, 12 load device, 14 charging device, 100 power system, 102 management server, 104 energy storage system, 106 connection terminal, 107 connection terminal, 108 wiring, 110 energy storage module, 112 positive terminal, 114 negative terminal, 120 energy storage module, 122 positive terminal, 124 negative terminal, 140 system control unit, 210 energy storage unit, 212 positive terminal, 214 negative terminal, 222 energy storage cell, 224 energy storage cell, 230 switching unit, 240 module control unit, 250 protection unit, 260 balance correction unit, 420 solid line, 520 solid line, 620 solid line, 720 solid line, 820 storage unit, 830 correspondence information acquisition unit, 840 data collection unit, 852 fluctuation detection unit, 854 Determination unit, 856 index derivation unit, 858 integrated value derivation unit, 860 cycle number estimation unit, 874 SOH derivation unit, 876 replacement time estimation unit, 922 information, 924 information, 3000 computer, 3001 DVD-ROM, 3010 host controller, 3012 CPU, 3014 RAM, 3016 graphic controller, 3018 display device, 3020 input / output controller, 3022 communication interface, 3024 hard disk drive, 3026 DVD-ROM drive, 3030 ROM, 3040 input / output chip, 3042 keyboard

Claims

1. A fluctuation detection unit that detects a fluctuation in a state of charge (SOC) of the storage battery; an index value derivation unit that derives a value of a stress index, which is an index indicating a ratio of a degree of stress applied to the storage battery due to the fluctuation detected by the fluctuation detection unit to a degree of stress applied to the storage battery due to the charging and discharging when the storage battery is charged and discharged, with full charging and full discharging being one cycle; an integrated value derivation unit that derives an integrated value of the value of the stress index in either a charging period in which the storage battery is charged or a discharging period in which the storage battery is discharged, based on the value of the stress index when the degree of the fluctuation satisfies a predetermined condition; An information processing device comprising:

2. The predetermined condition is: (i) the magnitude of the fluctuation is greater than a predetermined first threshold; (ii) the magnitude of the fluctuation in a reference period having a predetermined length is greater than the first threshold value; or (iii) a condition in which a ratio of the magnitude of the fluctuation to a reference value, which is a value of the state of charge of the storage battery at a reference time point, is greater than a predetermined second threshold value; Including, The information processing device according to claim 1 .

3. Further comprising a determination unit that determines whether the degree of the fluctuation satisfies the predetermined condition. The information processing device according to claim 1 .

4. The determination unit is (a) when discharging of the storage battery is started at a reference time point or when the storage battery is discharged at the reference time point, at least (i) when a first fluctuation amount, which is the absolute value of the difference between the minimum value of the state of charge of the storage battery during a first period from the reference time point to a first discharging time point that is a time point after the reference time point and is a time point at which the state of charge of the storage battery becomes greater than a reference value that is the value of the state of charge of the storage battery at the reference time point, and the reference value, is smaller than a predetermined first discharging threshold, or (ii) when a ratio of the first fluctuation amount to the reference value is smaller than a predetermined second discharging threshold, determining that the degree of the fluctuation does not satisfy the predetermined condition during the first period; The information processing device according to claim 3 .

5. The determination unit is (a) when discharging of the storage battery is started at a reference time point or when the storage battery is discharged at the reference time point, at least (iii) when a discharge amount, which is an absolute value of the difference between the state of charge of the storage battery and the reference value, becomes greater than a predetermined third discharge threshold before the state of charge of the storage battery becomes greater than a reference value, which is the value of the state of charge of the storage battery at the reference time point, or (iv) when a ratio of the discharge amount to the reference value becomes greater than a predetermined fourth discharge threshold before the state of charge of the storage battery becomes greater than the reference value, determining that the degree of the fluctuation satisfies the predetermined condition; The information processing device according to claim 3 .

6. The index value derivation unit derives the value of the stress index based on an absolute value of a difference between the reference value and a state of charge of the storage battery at a third discharging time point, which is the earliest time point at which charging of the storage battery is started after a second discharging time point, which is the time point at which the discharge amount becomes larger than the third discharging threshold or the ratio of the discharge amount to the reference value becomes larger than the fourth discharging threshold, or deriving the stress index value based on an absolute value of a difference between the state of charge of the storage battery at a fourth discharging time point, which is a time point at which the charge / discharge state of the storage battery changes from a discharging tendency to a charging tendency after the third discharging time point, and the reference value; The information processing device according to claim 5 .

7. a correspondence information acquisition unit that acquires, from a storage device that stores correspondence information indicating a correspondence relationship between a degree of variation in the state of charge of the storage battery and a degree of the stress index, the correspondence information; The index value derivation unit derives the stress index value based on an absolute value of a difference between the state of charge of the storage battery and the reference value and the correspondence relationship. The information processing device according to claim 6.

8. The determination unit updates the reference time point when it is determined that the degree of the fluctuation satisfies the predetermined condition, The updated reference point is: a second discharge time point, which is a time point when the discharge amount becomes larger than the third discharge threshold value or a time point when the ratio of the discharge amount to the reference value becomes larger than the fourth discharge threshold value; A third discharge time point, which is the earliest time point at which charging of the storage battery is started after the second discharge time point; or a fourth discharging time point at which the charge / discharge state of the storage battery changes from a discharging tendency to a charging tendency after the third discharging time point; That is, The information processing device according to claim 5 .

9. The determination unit is (b) when charging of the storage battery is started at a reference time point or when the storage battery is being charged at the reference time point, at least (i) when a second fluctuation amount, which is the absolute value of the difference between the maximum value of the state of charge of the storage battery during a second period that is a period from the reference time point to a first charging time point that is a time point after the reference time point and at which the state of charge of the storage battery becomes smaller than a reference value that is the value of the state of charge of the storage battery at the reference time point, and the reference value, is smaller than a predetermined first charging threshold, or (ii) when the ratio of the second fluctuation amount to the reference value is smaller than a predetermined second charging threshold, determining that the degree of the fluctuation does not satisfy the predetermined condition during the second period; The information processing device according to claim 3 .

10. The determination unit is (b) when charging of the storage battery is started at a reference time point or when the storage battery is being charged at the reference time point, at least (iii) when the charge amount, which is the absolute value of the difference between the state of charge of the storage battery and the reference value, becomes greater than a predetermined third charge threshold before the state of charge of the storage battery becomes smaller than a reference value, which is the value of the state of charge of the storage battery at the reference time point, or (iv) when the ratio of the charge amount to the reference value becomes greater than a predetermined fourth charge threshold before the state of charge of the storage battery becomes smaller than the reference value, determining that the degree of the fluctuation satisfies the predetermined condition; The information processing device according to claim 3 .

11. The index value derivation unit derives the value of the stress index based on an absolute value of a difference between the reference value and a state of charge of the storage battery at a third charging time point, which is the earliest time point at which discharging of the storage battery starts after a second charging time point, which is the time point at which the charged amount becomes greater than the third charging threshold or the ratio of the charged amount to the reference value becomes greater than the fourth charging threshold, or deriving the stress index value based on an absolute value of a difference between the state of charge of the storage battery at a fourth charging time point, which is a time point at which the charge / discharge state of the storage battery changes from a charging tendency to a discharging tendency after the third charging time point, and the reference value; The information processing device according to claim 10.

12. a correspondence information acquisition unit that acquires, from a storage device that stores correspondence information indicating a correspondence relationship between a degree of variation in the state of charge of the storage battery and a degree of the stress index, the correspondence information; The index value derivation unit derives the stress index value based on an absolute value of a difference between the state of charge of the storage battery and the reference value and the correspondence relationship. The information processing device according to claim 11.

13. The determination unit updates the reference time point when it is determined that the degree of the fluctuation satisfies the predetermined condition, The updated reference point is: a second charging time point, which is a time point when the charged amount becomes greater than the third charging threshold value or a time point when the ratio of the charged amount to the reference value becomes greater than the fourth charging threshold value; A third discharging time point, which is the earliest time point at which discharging of the storage battery is started after the second charging time point; or a fourth charging time point at which the charge / discharge state of the storage battery changes from a charging tendency to a discharging tendency after the third discharging time point; That is, The information processing device according to claim 10.

14. The fluctuation detection unit detects a fluctuation in a state of charge of each of a plurality of storage batteries connected in parallel between an input terminal and an output terminal, the index value derivation unit derives a value of the stress index for each of the plurality of storage batteries; the integrated value derivation unit derives, for each of the plurality of storage batteries, the integrated value of the value of the stress index in either the charging period or the discharging period of each storage battery; At least one of the plurality of storage batteries includes a plurality of storage cells connected in series. The information processing device according to claim 1 .

15. A program for causing a computer to function as the information processing device according to any one of claims 1 to 14.

16. a fluctuation detection stage of detecting a fluctuation in a state of charge (SOC) of the storage battery; an index value derivation step of deriving a value of a stress index which is an index indicating a ratio of a degree of stress applied to the storage battery due to the fluctuation detected in the fluctuation detection step to a degree of stress applied to the storage battery due to the charging and discharging when the storage battery is charged and discharged with full charging and full discharging being one cycle; an integrated value derivation step of deriving an integrated value of the value of the stress index in either a charging period during which the storage battery is charged or a discharging period during which the storage battery is discharged, based on the value of the stress index when the degree of the fluctuation satisfies a predetermined condition; An information processing method comprising the steps of:

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