Information processing device, information processing method, computer program, and information processing system

Abstract

To provide an information processing device, an information processing method, a computer program, and an information processing system with which it is possible to accurately determine the state of a storage battery.SOLUTION: An information processing device according to the present embodiment comprises a processing unit that: acquires a plurality of items of operation data, including the minimum voltage from among the voltages of a plurality of cells of a storage battery that includes the plurality of cells, the maximum voltage from among the voltages of the plurality of cells, and information with which it is possible to discriminate between charging and discharging of the storage battery; combines, on the basis of the plurality of items of operation data, one from among a charging maximum voltage group and a charging minimum voltage group and one from among a discharging maximum voltage group and a discharging minimum voltage group, and generates a voltage group to be evaluated; and determines the state of the storage battery on the basis of the voltage distribution of the voltage group to be evaluated.SELECTED DRAWING: Figure 1

Description

[Technical Field]

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

[0002] The use of secondary batteries (storage batteries) is increasing with the aim of stabilizing the power grid and reducing exhaust gas emissions in an effort to decarbonize. Even when a storage battery is operating normally, it gradually deteriorates depending on the frequency and duration of use. To avoid sudden battery failure, it is necessary to monitor the degree of deterioration (health) of the storage battery.

[0003] For example, a storage battery is constructed as a collection of battery modules connected in series or parallel, and the battery modules themselves are collections of battery cells. Therefore, to accurately grasp abnormalities in a storage battery, it is ideal to determine whether there is an abnormality at the module level or cell level (abnormality determination). However, to achieve such abnormality determination, operational data at the module or cell level is required. As the size of a storage battery increases, the number of modules and cells also increases, making it often difficult to accumulate data at the module and cell level.

[0004] To address this issue, there is a method for determining whether or not there is localized degradation based on the operating data of the storage battery, taking into account the state of each battery module. However, when using this method, even if there is no localized degradation, if there is a cell imbalance, it may be detected as an abnormality. In this case, it is not possible to determine whether there was localized degradation or a cell imbalance. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] International Publication No. 2021 / 044635 [Patent Document 2] Patent No. 6313502 [Patent Document 3] International Publication No. 2022 / 049745 Summary of the Invention [Problem to be solved by the invention]

[0006] The present embodiment provides an information processing device, an information processing method, a computer program, and an information processing system that are capable of accurately determining the state of a storage battery. [Means for solving the problem]

[0007] The information processing device of this embodiment includes a processing unit that acquires a plurality of operational data including a minimum voltage among the voltages of a storage battery including a plurality of battery cells, a maximum voltage among the voltages of the plurality of battery cells, and information that can identify charging or discharging of the storage battery, and generates a group of voltages to be evaluated based on the plurality of operational data by combining one of the group of maximum charging voltages and the group of minimum charging voltages with one of the group of maximum discharging voltages and the group of minimum discharging voltages, and determines the state of the storage battery based on the voltage distribution of the group of voltages to be evaluated. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a block diagram showing an example of a battery monitoring device that is an information processing device according to an embodiment of the present invention. [Figure 2] FIG. 1 illustrates an example of the configuration of a power storage system as one embodiment of a storage battery. [Figure 3A] FIG. 1 shows an example of the configuration of one module. [Figure 3B] A diagram showing an image of localized degradation and cell imbalance. [Figure 4] FIG. 10 is a diagram showing an example of an operation DB. [Figure 5] FIG. 10 is a diagram showing an example of voltage distribution. [Figure 6] FIG. 10 is a diagram showing another example of voltage distribution. [Figure 7]FIG. 2 is a diagram showing an example of a storage battery monitoring device that is a modified example of the device in FIG. 1. [Figure 8] FIG. 10 is a diagram showing an example of determination logic. [Figure 9] 10A and 10B are diagrams for explaining cases in which cell imbalance occurs. [Figure 10] FIG. 10 is a diagram illustrating a case where localized deterioration occurs. [Figure 11] 10A and 10B are diagrams illustrating a case where both cell imbalance and localized degradation occur. [Figure 12] FIG. 10 is another diagram illustrating a case where both cell imbalance and localized degradation occur. [Figure 13] 10 is a flowchart showing an example of processing by a determination unit. [Figure 14] FIG. 10 is a diagram showing an example of determination result data including the value of each ratio and the presence or absence of local deterioration or cell imbalance for each battery panel. [Figure 15] FIG. 10 is a diagram showing, in a table format, determination result data including the determination results for each battery panel in chronological order. [Figure 16] FIG. 10 is a diagram showing an example of output data including the values ​​of each ratio in time series. [Figure 17] 4 is a flowchart illustrating an example of the operation of the battery monitoring device according to the present embodiment. [Figure 18] FIG. 10 is a diagram showing an example of a battery monitoring device as an information processing device according to a second embodiment. [Figure 19] FIG. 10 is a diagram showing an example of case data. [Figure 20] FIG. 11 is a diagram showing an example of a battery monitoring device as an information processing device according to a third embodiment. [Figure 21] FIG. 1 is a diagram showing an example of the hardware configuration of a battery monitoring device according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0010] 1 is a block diagram of an example of an information processing system 10 including a battery monitoring device 100, which is an information processing device according to this embodiment. The information processing system 10 includes a battery 11, an operation DB 101, and the battery monitoring device 100. The battery monitoring device 100 includes an input unit 102, a processing unit 120, and an output unit 109.

[0011] The storage battery 11 is a battery that can be repeatedly charged and discharged. The storage battery 11 is also called a secondary battery, as opposed to a primary battery that can only discharge, but will be referred to as a storage battery hereinafter. In this embodiment, the term "charging and discharging" includes at least one of charging and discharging.

[0012] The storage battery 11 may be used for any purpose. For example, the storage battery 11 may be a storage battery for power supply purposes that stores electricity and then operates, such as a battery installed in a mobile object that operates using electrical energy as a power source, such as an electric vehicle (EV), an electric bus, a train, a next-generation light rail transit system (LRT), a bus rapid transit system (BRT), an automated guided vehicle (AGV), an airplane, or a ship, or a battery installed in industrial equipment. Alternatively, the storage battery may be a storage battery such as a stationary storage battery used for frequency fluctuation suppression in a power system. The storage battery may also be a storage battery for other purposes. The storage battery may be a battery used for a single purpose or for multiple purposes. For example, the storage battery may be a battery that was used for frequency fluctuation suppression and then reused to be used as a power source for an EV or the like or for storing power for demand response.

[0013] FIG. 2 shows an example configuration of a power storage system 201 as one form of the storage battery 11. The power storage system 201 includes battery panels (battery packs) 1, 2, ... N. The multiple battery panels are connected in series, in parallel, or in series and parallel so as to obtain the desired output depending on the use of the storage battery. Each battery panel includes multiple modules. Battery panel 1 includes modules 1-1 to 1-M, battery panel 2 includes modules 2-1 to 2-M, and battery panel N includes modules N-1 to NM. The multiple modules in each battery panel are connected in series, in parallel, or in series and parallel. In this example, each battery panel includes the same number of modules, but this does not have to be the same.

[0014] FIG. 3A shows an example of the configuration of one module. The module includes multiple battery cells C. Battery cells are also called cells. The multiple battery cells C are connected in series, in parallel, or in series and parallel. As an example, two or more battery cells C are connected in series and then connected in parallel.

[0015] In this embodiment, the storage battery to be evaluated (target storage battery) is a battery panel, a module, or a power storage system. The device 100 detects abnormalities in the storage battery. More specifically, the device 100 determines whether or not there is cell imbalance and whether or not there is localized deterioration in the storage battery.

[0016] Figure 3B(A) shows an image of localized degradation. Localized degradation occurs in cell C, which is indicated by diagonal lines. Localized degradation occurs when a portion of multiple cells is locally degraded.

[0017] Figure 3B(B) shows an image of cell imbalance. The shaded cell C has a large SoC, while the other cells C have small SoCs. In other words, there is variation in the SoCs of the multiple cells C. This variation in the SoCs of the multiple cells indicates a cell imbalance. Variation can mean, for example, that the standard deviation of the SoCs of the multiple cells is greater than a certain value, or that the difference in the SoCs of any two cells is greater than a certain value, or it can be defined in other ways.

[0018] The battery monitoring device 100 is connected to an operation DB 101. The operation DB 101 stores operation data acquired from one or more storage batteries 11 in chronological order. The operation data may be data acquired from an operating storage battery when the storage battery is used for an actual purpose, or may be data acquired through experiments. The operation data may be acquired per module, battery panel, or set of multiple battery panels. Operation data may be acquired for multiple acquisition units. The operation data may be acquired per module or battery panel, as long as it is a collection of battery cells. The maximum cell voltage and minimum cell voltage are the voltages of the battery cell with the maximum voltage and the battery cell with the minimum voltage among all battery cells in the data acquisition unit. The battery cell voltage is also referred to as cell voltage. The maximum cell voltage and minimum cell voltage values ​​are values ​​known by the storage battery or power storage system to prevent overcharging and over-discharging.

[0019] FIG. 4 shows an example of the operation DB 101. The operation data includes measurement data related to the storage battery 11. More specifically, the operation data includes a battery ID, time (measurement time), voltage value, SoC (State of Charge), power value, temperature, maximum cell voltage, and minimum cell voltage. The temperature is the temperature measured by the storage battery 11. Charging and discharging can be distinguished by whether the current or power is positive or negative. In other words, positive and negative are an example of information for identifying charging or discharging. A configuration may be adopted in which charging and discharging are distinguished by providing a charging / discharging flag, such as "charging" or "discharging." In this case, the charging / discharging flag corresponds to information for identifying charging or discharging.

[0020] The operation data may also include other information such as the use of the storage battery 11, humidity, or weather. For example, the operation data may also include a flag indicating the state of the storage battery when measurement data is acquired from the storage battery, such as charging, discharging, system operation (hereinafter referred to as operation), or system non-operation (hereinafter referred to as non-operation). The type of flag may vary depending on the type of storage battery. Examples of the types of storage batteries include, as mentioned above, storage batteries used to suppress frequency fluctuations in power systems and storage batteries (such as EV storage batteries). The operation data may also include a value indicating the state of the storage battery, specifically, the state of health (SoH) of the storage battery. The SoH indicates the degree of deterioration of the storage battery and is an index of the deterioration state indicating the extent to which the deterioration of the storage battery has progressed. For example, the SoH is defined as the battery capacity divided by the specified capacity of the storage battery. However, the definition of the SoH is not limited to this. For example, the SoH may be defined according to the magnitude of the internal resistance.

[0021] In the example of FIG. 4, the operation data is acquired at one-second intervals, but the acquisition interval may be another value, such as one minute, five minutes, or one hour. The acquisition interval may also vary depending on, for example, the time of day or the usage pattern of the storage battery, rather than being a fixed interval. The voltage value is the charging voltage value if the voltage is measured during charging, or the discharging voltage value if the voltage is measured during discharging. Instead of the power value, the operation data may include a current value. In this case, the battery monitoring device 100 may calculate the power value by integrating the current value and the voltage value. The SoC is an index indicating the charge level of the battery. For example, the SoC is calculated by dividing the amount of power (charge) stored in the storage battery by the specified capacity of the storage battery. If the operation data does not include the SoC but does include a current value, the battery monitoring device 100 may integrate the current value and calculate the SoC from the integrated value.

[0022] The input unit 102 acquires operation data from the operation DB 101 and provides the data to the voltage combination unit 103. The period during which the operation data is acquired is the period during which the storage battery 11 is to be evaluated.

[0023] The maximum charge voltage / minimum discharge voltage identifying unit 104 (hereinafter, identifying unit 104) identifies the maximum cell voltage (hereinafter, maximum charge voltage) for each piece of charging operation data among the operation data for the evaluation period, and acquires a group of maximum charge voltages. It also identifies the minimum cell voltage (hereinafter, minimum discharge voltage) for each piece of discharging operation data, and acquires a group of minimum discharge voltages. As described above, charging and discharging in the operation data are distinguished by the positive and negative values ​​of the current or power. For example, positive corresponds to discharging, and negative corresponds to charging. If the operation data includes a charging / discharging flag, charging and discharging may be distinguished based on the flag.

[0024] The minimum charge voltage / maximum discharge voltage specifying unit 105 (hereinafter, specifying unit 105) specifies the minimum charge cell voltage (hereinafter, minimum charge voltage) for each piece of charge operation data among the operation data for the evaluation period, and acquires a group of minimum charge voltages. Also, it specifies the maximum discharge cell voltage (hereinafter, maximum discharge voltage) for each piece of discharge operation data, and acquires a group of maximum discharge voltages.

[0025] The voltage combination unit 103 generates a group of voltages to be evaluated by combining one of the maximum charge voltage group and the minimum charge voltage group acquired by the identification units 104 and 105 with one of the minimum discharge voltage group and the maximum discharge voltage group. As an example, the voltage combination unit 103 generates a group of voltages to be evaluated, each consisting of a group of maximum charge voltages and a group of minimum discharge voltages, a group of minimum charge voltages and a group of maximum discharge voltages, a group of maximum charge voltages and a group of maximum discharge voltages, and a group of minimum charge voltages and a group of minimum discharge voltages. Although four groups (groups of voltages to be evaluated) are generated in this example, the number of groups to be generated may vary depending on the type of abnormality to be detected, as described below. For example, if it is desired to detect at least whether or not a cell imbalance has occurred, it may generate only a group of minimum charge voltages and a group of maximum discharge voltages.

[0026] The voltage distribution of the set of maximum charge voltage group and minimum discharge voltage group is described as voltage distribution (maximum charge voltage, minimum discharge voltage), the voltage distribution of the set of minimum charge voltage group and maximum discharge voltage group is described as voltage distribution (minimum charge voltage, maximum discharge voltage), the voltage distribution of the set of maximum charge voltage group and maximum discharge voltage group is described as voltage distribution (maximum charge voltage, maximum discharge voltage), and the voltage distribution of the set of minimum charge voltage group and minimum discharge voltage group is described as voltage distribution (minimum charge voltage, minimum discharge voltage).

[0027] The voltage spread calculation unit 106 (feature calculation unit) calculates a feature amount (called the degree of voltage spread) relating to the spread of the voltage distribution for each of the voltage distributions (maximum charging voltage, minimum discharging voltage), (minimum charging voltage, maximum discharging voltage), (maximum charging voltage, maximum discharging voltage), and (minimum charging voltage, minimum discharging voltage). A specific example of the degree of voltage spread will be shown using the voltage distribution (maximum charging voltage, minimum discharging voltage) as an example.

[0028] As an example, the degree of voltage spread is the standard deviation of the voltage distribution (maximum charge voltage, minimum discharge voltage). Alternatively, it is the difference between the maximum value and the minimum value of the voltage distribution (maximum charge voltage, minimum discharge voltage). Alternatively, it is the difference between the maximum value of the maximum charge voltage and the minimum value of the minimum discharge voltage in the voltage distribution (maximum charge voltage, minimum discharge voltage). The degree of voltage spread may also be defined in other ways.

[0029] The voltage spread calculation unit 106 also calculates the average cell voltage (average voltage) for each piece of operation data. The average voltage can be calculated, for example, by dividing the voltage included in the operation data by the number of cells connected in series. If the voltage of the operation data is module or battery panel data, the average cell voltage can be calculated by dividing the voltage by the number of cells connected in series. The average voltage may be included in the operation data. In this case, the average voltage can be obtained from the operation data. The voltage spread calculation unit 106 classifies the average voltage calculated for each piece of operation data into an average charging voltage (average charging voltage) and an average discharging voltage (average charging voltage) to obtain a group of average charging voltages and a group of average discharging voltages. The voltage distribution of the set of the average charging voltage group and the average discharging voltage group (reference voltage group) is referred to as a reference voltage distribution (average charging voltage, average discharging voltage). The voltage spread calculation unit 106 also calculates a feature quantity (degree of voltage spread) related to the spread of the voltage distribution for the reference voltage distribution (average charging voltage, average discharging voltage). The method for calculating the degree of voltage spread may be the same as the example described above.

[0030] An example of calculating the degree of voltage spreading will be shown using Figures 5 and 6. The explanations of Figures 5 and 6 can be applied to any of the five types of degree of voltage spreading described above.

[0031] FIG. 5 shows an example of calculating the degree of voltage spread from a voltage distribution. This voltage distribution may be any of the five types of voltage distributions mentioned above. This distribution has a shape close to a normal distribution. This distribution is obtained from a storage battery used for power conditioning, such as a stationary storage battery. In the case of such a distribution, the standard deviation can be calculated as the degree of voltage spread. FIG. 5 shows an example of calculating the standard deviation.

[0032] FIG. 6 shows another example of calculating the degree of voltage spread from a voltage distribution. This distribution has two peaks, one during charging and one during operation (discharging). This type of distribution is obtained from a storage battery used as a power source for electric vehicles and industrial equipment that temporarily stores electricity before operation. In the case of this type of distribution, the difference between the average voltage during charging and the average voltage during discharging can be used as the degree of voltage spread.

[0033] The device 100 may determine the intended use of the storage battery and determine the type of spread of the voltage distribution (feature value) to be calculated depending on the determined intended use. A feature value determination unit that determines the type of feature value depending on the intended use of the storage battery may be provided in the battery monitoring device 100 of FIG.

[0034] FIG. 7 shows an example of an information processing system 10A including a battery monitoring device 100A, which is a modified example of the device 100 in FIG. 1. A feature type determination unit 107 is added. The feature type determination unit 107 determines the intended use of the storage battery 11 and determines the type of feature to be calculated. As an example, the operation DB 101 may store type information indicating the intended use of the storage battery 11, and the feature type determination unit 107 may determine the intended use of the storage battery 11 based on the type information. Alternatively, the feature type determination unit 107 may determine the type of the storage battery 11 from the shape of the voltage distribution described above (see FIGS. 5 and 6).

[0035] Furthermore, a storage battery has a tendency that the more charged it is, the higher its open circuit voltage (OCV). To eliminate differences in open circuit voltage, the degree of voltage spread may be calculated according to the SoC. For this reason, the voltage combination unit 103 may generate the above-mentioned five types of voltage combinations (voltage groups to be evaluated) only for operation data having a specific SoC or operation data belonging to a specific SoC range. The input unit 102 may acquire only operation data having a specific SoC or operation data belonging to a specific SoC range from the operation DB 101.

[0036] The voltage spread degrees calculated from the five voltage distributions mentioned above (maximum charge voltage, minimum discharge voltage), (minimum charge voltage, maximum discharge voltage), (maximum charge voltage, maximum discharge voltage), (minimum charge voltage, minimum discharge voltage), and (average charge voltage, average discharge voltage) are referred to as voltage spread degrees (large-small), (small-large), (large-large), (small-small), and (average), respectively.

[0037] The local degradation / cell imbalance determination unit 108 (hereinafter referred to as the determination unit 108) performs a determination process to determine whether at least one of local degradation and cell imbalance has occurred based on the degree of voltage spread (large / small), (small / large), (large / large), (small / small), and (average). The determination process can result in four possible outcomes: local degradation has occurred, cell imbalance has occurred, both local degradation and cell imbalance have occurred, and neither local degradation nor cell imbalance has occurred.

[0038] The determination unit 108 calculates the ratios of the voltage spread degrees (large / small), (small / large), (large / large), (small / small) and (average) to the voltage spread degree, thereby obtaining the ratios (large / small), (small / large), (large / large), and (small / small). That is, the ratios (large / small), (small / large), (large / large), and (small / small) are calculated by dividing the voltage spread degrees (large / small), (small / large), (large / large), and (small / small) by the voltage spread degree (average), respectively.

[0039] The judgment unit 108 compares the ratios (large / small), (small / large), (large / large), and (small / small) with at least one threshold value, and judges whether local degradation and cell imbalance have occurred based on the comparison result and judgment logic.

[0040] FIG. 8 shows an example of the determination logic in the form of a determination table. Two thresholds, a lower threshold and an upper threshold, are used for the ratios (large / small), (small / large), (large / large), and (small / small). The lower threshold is 1-α1, and the upper threshold is 1+α2. α1 and α2 are both positive real numbers. α1 and α2 may be the same or different values. In the example of FIG. 8, the same threshold is used for the ratios (large / small), (small / large), (large / large), and (small / small). However, different thresholds may be used for each. For example, lower threshold 1-β1 and upper threshold 1+β2 may be used for the ratio (small / large), lower threshold 1-γ1 and upper threshold 1+γ2 may be used for the ratio (large / large), and lower threshold 1-θ1 and upper threshold 1+θ2 may be used for the ratio (small / small). The thresholds are predetermined and may vary depending on the temperature or battery type. The thresholds may also vary depending on the pattern of charge / discharge command values ​​executed by the storage battery 11. The storage battery 11 is assumed to charge or discharge at a specified power value at sampling intervals in accordance with the charge / discharge command value. The charge / discharge command value may be estimated from the power value included in the operation data and information identifying charge / discharge. Correspondence data that associates temperature, battery type, or charge / discharge command value patterns with thresholds is prepared in advance, and the threshold to be used is determined using this correspondence data.

[0041] The determination logic of FIG. 8 will be explained below. [Case 1] If the ratios (large / small), (small / large), (large / large), and (small / small) are all equal to or greater than the lower threshold 1-α1 and equal to or less than the upper threshold 1+α2, it is determined that neither local degradation nor cell imbalance has occurred. If α1 and α2 are sufficiently smaller than 1, and the ratios (large / small), (small / large), (large / large), and (small / small) are all around 1, it can be said that neither local degradation nor cell imbalance has occurred. In this embodiment, α1 and α2 are set to values ​​sufficiently smaller than 1. α1 and α2 are set to values ​​of, for example, 0.1 or less. 0.1 is merely an example, and larger values ​​may be set.

[0042] [Case 2] If the ratios (large / small), (large / large), and (small / small) are all greater than the upper threshold 1 + α2, and the ratio (small / large) is greater than or equal to the lower threshold 1 - α1 and less than or equal to the upper threshold 1 + α2, it is determined that local degradation has occurred.

[0043] [Case 3] If both the ratio (large-small) and (large-large) are greater than the upper threshold 1 + α2, and the ratio (small-large) is less than the lower threshold 1 - α1, it is determined that both local degradation and cell imbalance have occurred. The value of the ratio (small-small) can be any value. The "*" in the figure means don't care (any value is acceptable). Alternatively, if both the ratio (large / small) and (small / small) are greater than the upper threshold 1 + α2, and the ratio (small / large) is less than the lower threshold 1 - α1, it is determined that both local degradation and cell imbalance have occurred. The value of the ratio (large / large) can be any value.

[0044] [Case 4] If the ratio (large / small) is greater than the upper threshold 1 + α2, the ratio (small / large) is less than the lower threshold 1 - α1, and both the ratios (large / large) and (small / small) are greater than or equal to the lower threshold 1 - α1 and less than or equal to the upper threshold 1 + α2, it is determined that a cell imbalance has occurred.

[0045] The basis for the determination in the determination logic of FIG. 8 will be explained in detail for each case with reference to FIGS.

[0046] FIG. 9 is a diagram illustrating cases where cell imbalance occurs. The explanation is based on a coordinate system with the horizontal axis representing the SoC of the storage battery 11 and the vertical axis representing the voltage. The thick vertical arrow indicates the average degree of voltage spread of the average deteriorated cell. The dashed line schematically represents the OCV curve. Generally, the higher the charge amount, the higher the OCV, and the corresponding charge voltage and discharge voltage also increase.

[0047] Since no localized degradation has occurred, the degree of voltage spread of the average-degraded cells is approximately the same for all SoCs. Because cell balance is disrupted, there are average-degraded cells with different SoCs (here, the SoC of the cells, not the SoC of the battery module or battery panel). In this state, the maximum charge voltage, minimum charge voltage, minimum discharge voltage, and maximum discharge voltage are as shown in the figure. Since no localized degradation has occurred, the average-degraded cell has both the maximum charge voltage and the minimum discharge voltage. The voltage spread degrees (large / small), (small / large), (large / large), (small / small), and (average) are as shown by the arrows on the right side of the figure. The voltage spread degree (large / small) is greater than the voltage spread degree (average), and the voltage spread degree (small / large) is smaller than the voltage spread degree (average).

[0048] FIG. 10 is a diagram illustrating a case where localized degradation occurs. Because localized degradation has occurred, the voltage spread degree (very large) is larger than the voltage spread degree (average), unlike the case of cell imbalance in FIG. 9. The voltage spread degree (very small) is larger than the voltage spread degree (average), as in the case of cell imbalance. However, while in the case of cell imbalance, the average-degraded cell has both the maximum charge voltage and the minimum discharge voltage, in the case of localized degradation, the locally-degraded cell has both the maximum charge voltage and the minimum discharge voltage (see the vertically shaded arrow). The voltage spread degree (small large) is similar to the voltage spread degree (average), and the voltage spread degree (small small) is larger than the voltage spread degree (average).

[0049] 11 and 12 are diagrams illustrating cases where both cell imbalance and localized degradation occur. When both cell imbalance and localized degradation occur, the average-degraded cell has one of the maximum charge voltage and the minimum discharge voltage, and the locally degraded cell has the other. There are two patterns: when the average-degraded cell has the maximum charge voltage and when it has the minimum discharge voltage, and as shown in FIGS. 11 and 12, these are divided into two cases.

[0050] FIG. 11 shows a case where the average degraded cell has the maximum charge voltage and the locally degraded cell has the minimum discharge voltage. FIG. 12 shows a case where the locally degraded cell has the maximum charge voltage and the average degraded cell has the minimum discharge voltage. Comparing FIG. 11 and FIG. 12, in FIG. 11, the voltage spread degree (very large) is similar to the voltage spread degree (average), but the voltage spread degree (small small) is sufficiently larger than the voltage spread degree (average). On the other hand, in FIG. 12, the voltage spread degree (small small) is similar to the voltage spread degree (average), but the voltage spread degree (very large) is sufficiently larger than the voltage spread degree (average). In both FIG. 11 and FIG. 12, the voltage spread degree (large small) is larger than the voltage spread degree (average), and the voltage spread degree (small large) is smaller than the voltage spread degree (average).

[0051] In cases where neither cell imbalance nor local degradation occurs, the average degraded cells have the same or approximately the same SoC (here, the cell SoC), so the degree of voltage spread (large / small), (small / large), (large / large), (small / small) will be approximately the same as the degree of voltage spread (average) (not shown).

[0052] By combining the results of the case classification shown in FIGS. 9 to 12, the decision table shown in FIG. 8 can be derived.

[0053] In the determination table of FIG. 8, limited knowledge can be obtained by using some of the ratios. For example, if only the ratio (small / large) is used and the ratio (small / large) is smaller than the lower threshold 1-α1, it can be determined that at least a cell imbalance has occurred. Furthermore, if only the ratio (large / small) is used and the ratio (large / small) is about 1 (greater than or equal to the lower threshold and less than or equal to the upper threshold), it can be determined that neither a cell imbalance nor localized degradation has occurred. If the ratio (large / small) is greater than the upper threshold, it can be determined that at least one of a cell imbalance and localized degradation has occurred.

[0054] While the determination table in Fig. 8 shows a method for determining the presence or absence of cell imbalance and local degradation using the ratio to the voltage spread degree (average), the determination may also be made using the difference from the voltage spread degree (average). In that case, the lower threshold "1-α1" and the upper threshold "1+α2" in the determination table in Fig. 8 can be changed to "-α1" and "α2", respectively. In other words, the determination is made based on whether the difference between the voltage spread degree (large small), (small large), (large large), or (small small) and the voltage spread degree (average) is approximately 0 (greater than or equal to the lower threshold "-α1" and the upper threshold "α2"), greater than the upper threshold, or smaller than the lower threshold.

[0055] 13 is a flowchart showing an example of the process of the determination unit 108. The determination unit 108 performs the process in accordance with the procedure based on the determination table of FIG.

[0056] It is determined whether the ratio (large / small) is about 1 (greater than or equal to the lower threshold and less than or equal to the upper threshold) or greater than the upper threshold (S11). If it is about 1, it is determined that neither localized degradation nor cell imbalance has occurred (S12). From the determination table of FIG. 8, when the ratio (large / small) is about 1 (greater than or equal to the lower threshold and less than or equal to the upper threshold), it simply means that neither localized degradation nor cell imbalance has occurred, and therefore the determination can be made without referring to the values ​​of other types of ratios.

[0057] If the ratio (large / small) is greater than the upper threshold, it is determined whether the ratio (small / large) is approximately 1 or less than the lower threshold (S13). If the ratio (small / large) is approximately 1, it is determined that local degradation has occurred (S14).

[0058] If the ratio (large / small) is smaller than the lower threshold, it is determined whether the ratio (large / large) is about 1 or greater than the upper threshold (S15).If the ratio (large / large) is greater than the upper threshold, it is determined that both local degradation and cell imbalance have occurred (S16).

[0059] If the ratio (large large) is about 1, it is determined whether the ratio (small small) is about 1 or greater than the upper threshold (S17). If the ratio (small small) is greater than the upper threshold, it is determined that both local degradation and cell imbalance have occurred (S16). If the ratio (small small) is about 1, it is determined that cell imbalance has occurred (S18).

[0060] The above-described process is an example, and other procedures may be used as long as they conform to the determination table in Fig. 8. Furthermore, when it is determined in step S16 that both localized degradation and cell imbalance have occurred, if the ratio (very large) is greater than the upper threshold, it is possible to know that the locally degraded cell is out of balance in the direction of low charge. Furthermore, if the ratio (small small) is greater than the upper threshold, it is possible to know that the opposite is true, that is, that the locally degraded cell is out of balance in the direction of high charge.

[0061] The output unit 109 generates data indicating the determination result of the determination unit 108 and outputs it as determination result data. For example, the output unit 109 outputs the determination result data to a display device that can be viewed by the user.

[0062] 14 and 15 each show an example of the determination result data.

[0063] Figure 14 shows an example of the judgment result data for each battery panel (pack), including the value of each ratio and the presence or absence of an abnormality (local degradation or cell imbalance). The judgment result data in Figure 14 clearly shows which battery panels (packs) have been judged to be abnormal, and the value of each ratio at that time can also be confirmed.

[0064] Figure 15 shows the judgment result data in table format, which includes the judgment results for each battery panel (pack) in chronological order. The judgment result data in Figure 15 includes the judgment results for each month from March to August 2018. The judgment result data in Figure 15 allows you to comprehensively check the judgment results for each battery panel in chronological order.

[0065] The output unit 109 may output data indicating the value of each ratio together with the determination result data as shown in FIG. 14 or FIG. 15 or separately from the determination result data.

[0066] FIG. 16 shows an example of output data including the values ​​of each ratio in chronological order. The data is shown in graph form. The vertical axis represents the ratio value, and the horizontal axis represents time. However, the horizontal axis may also represent a value indicating the operating capacity of the storage battery, such as Ah or Wh (for example, the cumulative value of the charged and discharged current). The horizontal axis may also represent the number of cycles obtained by dividing the operating capacity by the rated value. Alternatively, the operating capacity and the number of cycles may be output in combination.

[0067] FIG. 17 shows a flowchart of an example of the operation of the battery monitoring device 100 according to this embodiment. The input unit 102 reads out operation data for an evaluation period from the operation DB 101 (S51). The voltage combination unit 103 causes the identification units 104 and 105 to identify the maximum charge voltage, minimum discharge voltage, minimum charge voltage, and maximum discharge voltage for each operation data. The voltage combination unit 103 combines these identified voltages to generate a set of a maximum charge voltage group and a minimum discharge voltage group, a set of a minimum charge voltage group and a maximum discharge voltage group, a set of a maximum charge voltage group and a maximum discharge voltage group, and a set of a minimum charge voltage group and a minimum discharge voltage group. Furthermore, the voltage combination unit 103 calculates the average voltage for each operation data and generates a set of an average charge voltage group and an average discharge voltage group (S52). The voltage spread calculation unit 106 calculates the degree of voltage spread (large / small), (small / large), (large / large), (small / small), and (average) as a feature based on the voltage distribution of each group (S53). The determination unit 108 calculates the ratio between each voltage spread degree (large / small), (small / large), (large / large), (small / small) and the voltage spread degree (average) to obtain the ratios (large / small), (small / large), (large / large), (small / small). The determination unit 108 determines the presence or absence of an abnormality by executing the process shown in Fig. 13 based on the obtained ratios (large / small), (small / large), (large / large), (small / small). The output unit 109 outputs data including the determination result by the determination unit 108 (determination result data).

[0068] As described above, according to this embodiment, it is possible to determine the occurrence of localized deterioration and cell imbalance in a storage battery without storing data (for example, voltage data) of all battery cells included in the storage battery.

[0069] (Second embodiment) In this embodiment, the lower and upper thresholds used in the first embodiment are determined by learning. 18 shows an example of an information processing system 10B including a battery monitoring device 100B as an information processing device according to the second embodiment. A threshold learning unit 110 and a case DB 111 are added to the battery monitoring device 100 of FIG.

[0070] The case DB 111 stores case data created based on operational data. The operational data from which the case data is generated may be operational data different from the operational DB 101 that stores the operational data to be evaluated. The case data may be stored in the case DB 111 in advance, or the device 100B may generate the case data from the operational data. In this case, the operational data is associated with the presence or absence of cell imbalance and local degradation.

[0071] FIG. 19 shows an example of case data. Each case contains a case ID, a battery ID, various ratio values, and whether or not cell imbalance and localized degradation have occurred. The case DB 111 stores cases in which cell imbalance has occurred, localized degradation, both of these, and neither of these. One operational data item corresponds to one case. While the presence or absence of localized degradation and cell imbalance is expressed as a binary value, a quantified value representing the degree of occurrence may also be used. For example, in the case of localized degradation, the difference between the SoH of the least degraded battery cell and the SoH of the most degraded battery cell may be used. In the case of cell imbalance, the difference between the SoC of the most charged battery cell and the SoC of the least charged battery cell may be used. Furthermore, operational data may be associated with each case instead of the ratios. In this case, the ratios can be calculated from the operational data.

[0072] The threshold learning unit 110 learns the lower and upper thresholds based on case data. For example, when performing an abnormality determination using the procedure in Fig. 13, the lower and upper thresholds are determined according to the procedure in Fig. 13 so that the determination result is correct. For example, in the branch at step S11 in Fig. 13, if the ratio (large / small) is about 1 (greater than or equal to the lower threshold and less than the upper threshold), it is determined that neither local degradation nor cell imbalance has occurred, so the lower and upper thresholds are determined so that this determination is correct. Specifically, the lower and upper thresholds should be determined so that the classification index such as precision or recall is high.

[0073] The determination unit 108 uses the lower and upper thresholds determined by the threshold learning unit 110 to make a determination based on the procedure of FIG. 13 or the determination table of FIG.

[0074] The method for determining whether local degradation and cell imbalance have occurred may be a method other than the method based on the procedure of FIG. 13 or the determination table of FIG. 8. For example, if a sufficient number of cases have been accumulated in the case DB 111, a classification model may be generated by machine learning using each ratio as an explanatory variable and the occurrence or non-occurrence of local degradation and cell imbalance as an objective variable. The determination unit 108 determines whether or not local degradation and cell imbalance have occurred based on the various ratios calculated from the operational data and the model generated by learning. Examples of classification models include decision trees, logistic regression, a neighborhood method, a support vector machine, a neural network, and a random forest.

[0075] There may also be a method for determining whether local degradation and cell imbalance have occurred without calculating various ratios. For example, multiple voltage distributions are prepared for each abnormality occurrence pattern in case data (local degradation only, cell imbalance only, both, and neither). A neural network is generated by machine learning, using a voltage group included in any one type of voltage distribution or a voltage group included in all types of voltage distributions as input, and outputting the presence or absence of local degradation and cell imbalance. Any one or all types of voltage distributions obtained based on operational data are input to the generated neural network, and the presence or absence of local degradation and cell imbalance is estimated.

[0076] (Third embodiment) 20 shows an example of an information processing system 10C including a battery monitoring device 100C as an information processing device according to the third embodiment. An SoH estimation unit 112 is added to the battery monitoring device 100B of the second embodiment. The SoH estimation unit 112 may also be added to the battery monitoring device 100 of the first embodiment or the battery monitoring device 100A of the first embodiment or a variation thereof.

[0077] The SoH estimation unit 112 estimates the State of Health (SoH) from each voltage spread degree (large / small), (small / large), (large / large), (small / small), and (average). The unit calculates a ratio between the SoH estimated from the voltage spread degree (large / small), (small / large), (large / large), and (small / small) and the SoH estimated from the voltage spread degree (average). Because the voltage spread degree correlates with the state of health (SoH) of the storage battery, a model for estimating the SoH from the voltage spread degree can be trained in advance for each voltage spread degree (large / small), (small / large), (large / large), (small / small), and (average). The SoH estimation unit 112 estimates each SoH based on the value of each voltage spread degree and the trained model corresponding to each voltage spread degree. The SoH estimation method disclosed in Japanese Patent Publication No. 6313502 or International Publication No. 2021 / 186512 may be used to estimate the SoH from the voltage spread. The voltage spread can vary depending on the battery temperature or the aforementioned charge / discharge command value pattern. Using the SoH can reduce these effects. Therefore, calculating the ratio using the SoH is expected to enable more stable abnormality detection. When calculating the ratio using the SoH, the comparison of whether the value is greater than the upper threshold and whether it is less than the lower threshold in the determination table of FIG. 8 is reversed. For example, in the case of the ratio (large / small), ">1 + α2" (greater than the upper threshold), which corresponds to the occurrence of localized degradation (Case 2), is changed to "<1 - α1" (less than the lower threshold).

[0078] (Hardware configuration) Figure 21 shows an example of the hardware configuration of a battery monitoring device according to an embodiment of the present invention. This hardware configuration can be used for the battery monitoring devices 100, 100A, 100B, and 100C according to the above-mentioned embodiments. The hardware configuration of Figure 21 is configured as a computer 150. The computer 150 includes a CPU 151, an input interface 152, a display device 153, a communication device 154, a main memory device 155, and an external memory device 156, which are connected to each other via a bus 157 so that they can communicate with each other.

[0079] The input interface 152 acquires measurement data of the storage battery via wiring or the like. The input interface 152 may be an operating means by which the user gives instructions to the device. Examples of the operating means include a keyboard, a mouse, and a touch panel. The communication device 154 includes wireless or wired communication means and performs wired or wireless communication with the EV 200. The measurement data may be acquired via the communication device 154. The input interface 152 and the communication device 154 may each be configured as separate circuits such as integrated circuits, or may be configured as a single circuit such as an integrated circuit. The display device 153 is, for example, a liquid crystal display device, an organic EL display device, a CRT display device, or the like. The display device 153 corresponds to the output unit 109 in FIG. 1.

[0080] The external storage device 156 includes, for example, storage media such as an HDD, SSD, memory device, CD-R, CD-RW, DVD-RAM, DVD-R, etc. The external storage device 156 stores programs for causing the CPU 151, which is a processor, to execute the functions of each processing unit of the battery monitoring device. Each DB provided in the battery monitoring device is also included in the external storage device 156. Although only one external storage device 156 is shown here, multiple external storage devices 156 may be present.

[0081] Under the control of CPU 151, main memory device 155 loads the control program stored in external memory device 156 and stores data required when executing the program, data generated by the execution of the program, etc. Main memory device 155 includes any memory or storage unit, such as volatile memory (DRAM, SRAM, etc.) or non-volatile memory (NAND flash memory, MRAM, etc.). The control program loaded in main memory device 155 is executed by CPU 151, thereby executing the functions of each processing unit of the storage battery monitoring device. Each DB provided in the storage battery monitoring device may also be included in main memory device 155.

[0082] The present invention is not limited to the above-described embodiments, and the components can be modified and embodied in practice without departing from the spirit of the invention. Furthermore, various inventions can be created by appropriately combining multiple components disclosed in the above-described embodiments. For example, configurations in which some components are omitted from all the components shown in each embodiment may also be considered. Furthermore, components described in different embodiments may be appropriately combined.

[0083] This embodiment can also be configured as follows. [Note] [Item 1] acquiring a plurality of pieces of operational data including a minimum voltage among the voltages of a plurality of battery cells of a storage battery including the plurality of battery cells, a maximum voltage among the voltages of the plurality of battery cells, and information that can identify whether the storage battery is being charged or discharged; generating an evaluation target voltage group by combining one of the maximum charging voltage group and the minimum charging voltage group with one of the maximum discharging voltage group and the minimum discharging voltage group based on the plurality of operation data; a processing unit that determines a state of the storage battery based on a voltage distribution of the evaluation target voltage group. An information processing device comprising: [Item 2] The processing unit generates a first voltage group as the evaluation target voltage group by combining the minimum charging voltage group and the maximum discharging voltage group, and determines whether or not a cell imbalance, which is a variation in the charge amounts of the plurality of battery cells, has occurred as the state of the storage battery based on the first voltage group. Item 1. An information processing device according to item 1. [Item 3] The processing unit generates a second voltage group as the evaluation target voltage group by combining the maximum charging voltage group and the maximum discharging voltage group, and determines whether local degradation, which is local degradation of some of the plurality of battery cells, is also occurring at the same time as the cell imbalance, based on the second voltage group. Item 2. An information processing device according to item 2. [Item 4] The processing unit generates a third voltage group by combining the minimum charging voltage group and the minimum discharging voltage group as the evaluation target voltage group, and determines whether the local degradation has occurred simultaneously with the cell imbalance based on the third voltage group. Item 2 or 3. The information processing device according to item 2 or 3. [Item 5] The processing unit generates a fourth voltage group as the evaluation target voltage group by combining the maximum charging voltage group and the minimum discharging voltage group, and determines whether at least one of the cell imbalance and the local degradation has occurred based on the fourth voltage group. Item 3. The information processing device according to item 3 or 4. [Item 6] the operational data includes a voltage of the storage battery or an average voltage of the plurality of battery cells during the charging or discharging; the processing unit calculates or acquires an average voltage of the plurality of battery cells based on the operation data, and calculates a voltage distribution of an average voltage group of the plurality of battery cells during the charging and discharging; The state of the storage battery is determined by comparing the voltage distribution of the evaluation target voltage group with the voltage distribution of the average voltage group. 6. The information processing device according to any one of items 1 to 5. [Item 7] The processing unit calculates a feature amount representing a spread of the voltage distribution of the evaluation target voltage group and a reference feature amount representing a spread of the voltage distribution of the average voltage group, and determines the state of the storage battery based on a ratio between the calculated feature amount and the reference feature amount. Item 7. An information processing device according to item 6. [Item 8] The processor determines the state of the battery by comparing the ratio to at least one threshold. Item 7. An information processing device according to item 7. [Item 9] The processing unit generates a first voltage group by combining the minimum charging voltage group and the maximum discharging voltage group as the evaluation target voltage group, and determines whether or not a cell imbalance, which is a variation in the charge amounts of the plurality of battery cells, has occurred by comparing a first ratio between a first feature amount representing a spread of a voltage distribution of the first voltage group and the reference feature amount with the at least one threshold value. Item 9. An information processing device according to item 8. [Item 10] The processing unit further generates a second voltage group by combining the maximum charging voltage group and the maximum discharging voltage group as the evaluation target voltage group, and determines whether local degradation, which is local degradation of some of the plurality of battery cells, is also occurring simultaneously with the cell imbalance by comparing a second ratio between a second feature amount representing a spread of a voltage distribution of the second voltage group and the reference feature amount with the at least one threshold value. Item 10. The information processing device according to item 9. [Item 11] The processing unit further generates a third voltage group by combining the minimum charging voltage group and the minimum discharging voltage group as the evaluation target voltage group, and determines whether the local degradation has occurred simultaneously with the cell imbalance by comparing a third ratio between the reference characteristic amount and a third characteristic amount representing a spread of a voltage distribution of the third voltage group with the at least one threshold value. Item 11. The information processing device according to item 9 or 10. [Item 12] The processing unit generates a fourth voltage group by combining the maximum charging voltage group and the minimum discharging voltage group as the evaluation target voltage group, and determines whether at least one of the cell imbalance and the local degradation has occurred by comparing a fourth ratio of a fourth feature amount representing a spread of a voltage distribution of the fourth voltage group to the reference feature amount with the at least one threshold value. Item 12. The information processing device according to item 10 or 11. [Item 13] The processing unit estimates an SoH of the storage battery based on the feature amount, estimates a reference SoH that is the SoH of the storage battery based on the reference feature amount, and determines a state of the storage battery based on a ratio between the SoH and the reference SoH. The information processing device according to any one of items 7 to 12. [Item 14] The processor determines the state of the battery by comparing the ratio to at least one threshold. Item 14. The information processing device according to item 13. [Item 15] The processing unit generates a first voltage group by combining the minimum charging voltage group and the maximum discharging voltage group as the evaluation target voltage group, and determines whether or not a cell imbalance, which is a variation in charge amount among the plurality of battery cells, has occurred as the state of the storage battery based on a first ratio between a first feature amount representing a spread of a voltage distribution of the first voltage group and the reference feature amount. Item 15. An information processing device according to item 14. [Item 16] The processing unit further generates a second voltage group by combining the maximum charging voltage group and the maximum discharging voltage group as the evaluation target voltage group, and determines whether local degradation, which is local degradation of some of the plurality of battery cells, is also occurring simultaneously with the cell imbalance by comparing a second ratio between a second feature amount representing a spread of a voltage distribution of the second voltage group and the reference feature amount with the at least one threshold value. Item 16. An information processing device according to item 15. [Item 17] The processing unit further generates a third voltage group by combining the minimum charging voltage group and the minimum discharging voltage group as the evaluation target voltage group, and determines whether the local degradation has occurred simultaneously with the cell imbalance by comparing a third ratio between the reference characteristic amount and a third characteristic amount representing a spread of a voltage distribution of the third voltage group with the at least one threshold value. Item 17. The information processing device according to item 15 or 16. [Item 18] The processing unit generates a fourth voltage group by combining the maximum charging voltage group and the minimum discharging voltage group as the evaluation target voltage group, and determines whether at least one of the cell imbalance and the local degradation has occurred by comparing a fourth ratio of a fourth feature amount representing a spread of a voltage distribution of the fourth voltage group to the reference feature amount with the at least one threshold value. Item 18. The information processing device according to item 16 or 17. [Item 19] The processing unit determines the at least one threshold value based on a temperature of the storage battery or a charge / discharge command value pattern of the storage battery. 19. The information processing device according to any one of items 8 to 18. [Item 20] The processing unit learns the at least one threshold value based on a plurality of case data including the first ratio, the second ratio, the third ratio, the fourth ratio, the presence or absence of the cell imbalance, and the presence or absence of the local degradation. 20. The information processing device according to any one of items 8 to 19. [Item 21] acquiring a plurality of pieces of operational data including a minimum voltage among the voltages of a plurality of battery cells of a storage battery including the plurality of battery cells, a maximum voltage among the voltages of the plurality of battery cells, and information that can identify whether the storage battery is being charged or discharged; generating an evaluation target voltage group by combining one of the maximum charging voltage group and the minimum charging voltage group with one of the maximum discharging voltage group and the minimum discharging voltage group based on the plurality of operation data; The state of the storage battery is determined based on the voltage distribution of the voltage group to be evaluated. Information processing methods. [Item 22] acquiring a plurality of pieces of operational data including a minimum voltage among voltages of a plurality of battery cells of a storage battery including the plurality of battery cells, a maximum voltage among voltages of the plurality of battery cells, and information that can identify whether the storage battery is being charged or discharged; generating a group of voltages to be evaluated by combining one of the group of maximum charging voltages and the group of minimum charging voltages with one of the group of maximum discharging voltages and the group of minimum discharging voltages based on the plurality of operation data; determining the state of the storage battery based on the voltage distribution of the voltage group to be evaluated; A computer program for causing a computer to execute the above. [Item 23] a storage battery including a plurality of battery cells; a processing unit that acquires a plurality of operation data including a minimum voltage among the voltages of the plurality of battery cells, a maximum voltage among the voltages of the plurality of battery cells, and information that can identify charging or discharging of the storage battery, generates an evaluation target voltage group based on the plurality of operation data by combining one of the group of maximum charging voltages and the group of minimum charging voltages with one of the group of maximum discharging voltages and the group of minimum discharging voltages, and determines a state of the storage battery based on a voltage distribution of the group of voltages to be evaluated; An information processing system comprising: [Explanation of symbols]

[0084] 1~N: Battery panel (battery pack, storage battery) 1-1~1-M Module (storage battery) 10, 10A, 10B, 10C Information Processing Systems 11 Storage battery 100, 100A, 100B, 100C storage battery monitoring device 101 Operating DB 102 Input section 103 Generation part 104 Charging maximum voltage / discharging minimum voltage specification section 105 Minimum charge voltage / maximum discharge voltage specification section 106 Voltage spread calculation unit (feature calculation unit) 107 Feature type determination unit 108 Local Degradation / Cell Balance Determination Unit (Determination Unit) 109 Output section 110 Threshold learning unit 111 Case DB 112 SoH estimation section 120 Processing section 150 Computers 152 Input Interface 153 Display device 154 Communication equipment 155 Main memory 156 External storage device 157 Bus 201 Energy Storage System C Battery cell

Claims

1. acquiring a plurality of pieces of operational data including a minimum voltage among the voltages of a plurality of battery cells of a storage battery including the plurality of battery cells, a maximum voltage among the voltages of the plurality of battery cells, and information that can identify whether the storage battery is being charged or discharged; a processing unit that generates a first voltage group by combining the charging minimum voltage group and the discharging maximum voltage group based on the plurality of operation data, generates a second voltage group by combining the charging maximum voltage group and the discharging maximum voltage group, and determines, based on the first voltage group and the second voltage group, whether or not a cell imbalance, which is a variation in the charge amounts of the plurality of battery cells, and local degradation, which is local degradation of some of the plurality of battery cells, are occurring as the state of the storage battery. An information processing device comprising:

2. The processing unit generates a third voltage group by combining the charging minimum voltage group and the discharging minimum voltage group, and determines whether the local degradation has occurred simultaneously with the cell imbalance based on the third voltage group. The information processing device according to claim 1 .

3. The processing unit generates a fourth voltage group by combining the maximum voltage group for charging and the minimum voltage group for discharging, and determines whether at least one of the cell imbalance and the local degradation has occurred based on the fourth voltage group. The information processing device according to claim 2 .

4. A storage battery including a plurality of battery cells is provided with a plurality of operation data including a minimum voltage among the voltages of the plurality of battery cells, a maximum voltage among the voltages of the plurality of battery cells, information that can identify charging or discharging of the storage battery, and the voltage of the storage battery or an average voltage of the plurality of battery cells during charging or discharging; generating a group of voltages to be evaluated by combining one of the group of maximum charging voltages and the group of minimum charging voltages with one of the group of maximum discharging voltages and the group of minimum discharging voltages based on the plurality of operation data; Calculating or acquiring an average voltage of the plurality of battery cells based on the plurality of operation data, and calculating a voltage distribution of an average voltage group of the plurality of battery cells during the charging and discharging; a processing unit that determines the state of the storage battery by comparing the voltage distribution of the evaluation target voltage group with the voltage distribution of the average voltage group; An information processing device comprising:

5. The processing unit calculates a feature amount representing a spread of the voltage distribution of the evaluation target voltage group and a reference feature amount representing a spread of the voltage distribution of the average voltage group, and determines the state of the storage battery based on a ratio between the calculated feature amount and the reference feature amount. The information processing device according to claim 4 .

6. The processor determines the state of the battery by comparing the ratio to at least one threshold. The information processing device according to claim 5 .

7. The processing unit generates a first voltage group by combining the minimum charging voltage group and the maximum discharging voltage group as the evaluation target voltage group, and determines whether or not a cell imbalance, which is a variation in the charge amounts of the plurality of battery cells, has occurred by comparing a first ratio between a first feature amount representing a spread of a voltage distribution of the first voltage group and the reference feature amount with the at least one threshold value. The information processing device according to claim 6 .

8. The processing unit further generates a second voltage group as the evaluation target voltage group by combining the maximum charging voltage group and the maximum discharging voltage group, and determines whether local degradation, which is local degradation of some of the plurality of battery cells, is also occurring simultaneously with the cell imbalance by comparing a second ratio of a second feature amount representing a spread of a voltage distribution of the second voltage group to the reference feature amount with the at least one threshold value. The information processing device according to claim 7 .

9. The processing unit further generates a third voltage group by combining the minimum charging voltage group and the minimum discharging voltage group as the evaluation target voltage group, and determines whether the local degradation has occurred simultaneously with the cell imbalance by comparing a third ratio of a third feature amount representing a spread of a voltage distribution of the third voltage group to the reference feature amount with the at least one threshold value. The information processing device according to claim 8 .

10. The processing unit generates a fourth voltage group by combining the maximum charging voltage group and the minimum discharging voltage group as the evaluation target voltage group, and determines whether at least one of the cell imbalance and the local degradation has occurred by comparing a fourth ratio of a fourth feature amount representing a spread of a voltage distribution of the fourth voltage group to the reference feature amount with the at least one threshold value. The information processing device according to claim 9 .

11. The processing unit estimates the SoH of the storage battery based on the feature amount, estimates a reference SoH that is the SoH of the storage battery based on the reference feature amount, and determines the state of the storage battery based on a ratio between the SoH and the reference SoH. The information processing device according to claim 5 .

12. The processor determines the state of the battery by comparing the ratio to at least one threshold. The information processing device according to claim 11.

13. The processing unit generates a first voltage group as the evaluation target voltage group by combining the minimum charging voltage group and the maximum discharging voltage group, and determines whether or not a cell imbalance, which is a variation in charge amount among the plurality of battery cells, has occurred as the state of the storage battery based on a first ratio between a first feature amount representing a spread of a voltage distribution of the first voltage group and the reference feature amount. The information processing device according to claim 12.

14. The processing unit further generates a second voltage group as the evaluation target voltage group by combining the maximum charging voltage group and the maximum discharging voltage group, and determines whether local degradation, which is local degradation of some of the plurality of battery cells, is also occurring simultaneously with the cell imbalance by comparing a second ratio of a second feature amount representing a spread of a voltage distribution of the second voltage group to the reference feature amount with the at least one threshold value. The information processing device according to claim 13.

15. The processing unit further generates a third voltage group by combining the minimum charging voltage group and the minimum discharging voltage group as the evaluation target voltage group, and determines whether the local degradation has occurred simultaneously with the cell imbalance by comparing a third ratio of a third feature amount representing a spread of a voltage distribution of the third voltage group to the reference feature amount with the at least one threshold value. The information processing device according to claim 14.

16. The processing unit generates a fourth voltage group by combining the maximum charging voltage group and the minimum discharging voltage group as the evaluation target voltage group, and determines whether at least one of the cell imbalance and the local degradation has occurred by comparing a fourth ratio of a fourth feature amount representing a spread of a voltage distribution of the fourth voltage group to the reference feature amount with the at least one threshold value. The information processing device according to claim 15.

17. The processing unit determines the at least one threshold value based on a temperature of the storage battery or a charge / discharge command value pattern of the storage battery. The information processing device according to any one of claims 6 to 10 and 12 to 16.

18. The processing unit learns the at least one threshold value based on a plurality of case data including the first ratio, the second ratio, the third ratio, the fourth ratio, the presence or absence of the cell imbalance, and the presence or absence of the local degradation.

17. The information processing device according to claim 10 or 16.

19. acquiring a plurality of pieces of operational data including a minimum voltage among the voltages of a plurality of battery cells of a storage battery including the plurality of battery cells, a maximum voltage among the voltages of the plurality of battery cells, and information that can identify whether the storage battery is being charged or discharged; a first voltage group is generated by combining the minimum charging voltage group and the maximum discharging voltage group based on the plurality of operation data, a second voltage group is generated by combining the maximum charging voltage group and the maximum discharging voltage group, and based on the first voltage group and the second voltage group, it is determined whether or not the state of the storage battery is experiencing cell imbalance, which is a variation in the charge amounts of the plurality of battery cells, as well as local degradation, which is local degradation of some of the plurality of battery cells. Information processing methods.

20. A storage battery including a plurality of battery cells is provided with a plurality of operation data including a minimum voltage among the voltages of the plurality of battery cells, a maximum voltage among the voltages of the plurality of battery cells, information that can identify whether the storage battery is being charged or discharged, and the voltage of the storage battery or an average voltage of the plurality of battery cells during the charging or discharging, generating a group of voltages to be evaluated by combining one of the group of maximum charging voltages and the group of minimum charging voltages with one of the group of maximum discharging voltages and the group of minimum discharging voltages based on the plurality of operation data; Calculating or acquiring an average voltage of the plurality of battery cells based on the plurality of operation data, and calculating a voltage distribution of an average voltage group of the plurality of battery cells during the charging and discharging; determining the state of the storage battery by comparing the voltage distribution of the evaluation target voltage group with the voltage distribution of the average voltage group; Information processing methods.

21. acquiring a plurality of pieces of operational data including a minimum voltage among voltages of a plurality of battery cells of a storage battery including the plurality of battery cells, a maximum voltage among voltages of the plurality of battery cells, and information that can identify whether the storage battery is being charged or discharged; generating a first voltage group by combining the charging minimum voltage group and the discharging maximum voltage group based on the plurality of operation data; generating a second voltage group by combining the charging maximum voltage group and the discharging maximum voltage group based on the plurality of operation data; determining, based on the first voltage group and the second voltage group, whether or not the state of the storage battery is experiencing cell imbalance, i.e., variation in charge amounts among the plurality of battery cells, as well as local degradation, i.e., local degradation of some of the plurality of battery cells; A computer program for causing a computer to execute the above.

22. A step of acquiring a plurality of operational data including the minimum voltage among the voltages of the plurality of battery cells of a storage battery including the plurality of battery cells, the maximum voltage among the voltages of the plurality of battery cells, information capable of identifying charging or discharging of the storage battery, and the voltage of the storage battery or the average voltage of the plurality of battery cells during the charging or discharging; generating a group of voltages to be evaluated by combining one of the group of maximum charging voltages and the group of minimum charging voltages with one of the group of maximum discharging voltages and the group of minimum discharging voltages based on the plurality of operation data; calculating or acquiring average voltages of the plurality of battery cells based on the plurality of operation data, and calculating a voltage distribution of average voltages of the plurality of battery cells during the charging and discharging; determining the state of the storage battery by comparing the voltage distribution of the evaluation target voltage group with the voltage distribution of the average voltage group; A computer program for causing a computer to execute the above.

23. a storage battery including a plurality of battery cells; a processing unit that acquires a plurality of pieces of operation data including a minimum voltage among the voltages of the plurality of battery cells, a maximum voltage among the voltages of the plurality of battery cells, and information that can identify charging or discharging of the storage battery, generates a first voltage group that combines the group of minimum charging voltages and the group of maximum discharging voltages based on the plurality of operation data, generates a second voltage group that combines the group of maximum charging voltages and the group of maximum discharging voltages, and determines, based on the first voltage group and the second voltage group, whether or not local degradation, which is local degradation of some of the plurality of battery cells, is occurring as a state of the storage battery. An information processing system comprising:

24. A storage battery including a plurality of battery cells; acquiring a plurality of pieces of operational data including a minimum voltage among the voltages of the plurality of battery cells of a storage battery including the plurality of battery cells, a maximum voltage among the voltages of the plurality of battery cells, information capable of identifying whether the storage battery is being charged or discharged, and the voltage of the storage battery or an average voltage of the plurality of battery cells during the charging or discharging; generating a group of voltages to be evaluated by combining one of the group of maximum charging voltages and the group of minimum charging voltages with one of the group of maximum discharging voltages and the group of minimum discharging voltages based on the plurality of operation data; Calculating or acquiring an average voltage of the plurality of battery cells based on the plurality of operation data, and calculating a voltage distribution of an average voltage group of the plurality of battery cells during the charging and discharging; a processing unit that determines the state of the storage battery by comparing the voltage distribution of the evaluation target voltage group with the voltage distribution of the average voltage group; An information processing system comprising:

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