Information processing method and charging control device

Abstract

An information processing method executed by a computer executes the following steps: instructing a charging device that charges a battery to repeatedly perform charging control including a set of charging during a first period and stopping charging during a second period, and to end the charging control if a charging amount reaches a prescribed amount; and acquiring operation data indicating a voltage and a charging capacity of the battery at a time of ending each of the second periods in the charging control.

Description

Technical Field

[0001] This invention relates to a technique for analyzing the degradation state of rechargeable batteries. Background Technology

[0002] Previously, the dV / dQ method was known as a non-destructive analysis method for analyzing the degradation of secondary battery components such as the cathode and anode without damaging the battery itself. In this method, the secondary battery is charged or discharged at an extremely low rate, and the open-circuit voltage (OCV) is acquired over time. Then, based on the differential value representing the change in open-circuit voltage relative to the change in the battery's charging capacity, the degradation state of the secondary battery is inferred.

[0003] For example, Patent Document 1 discloses a differential curve Q-dV / dQ that calculates the relationship between the differential value dV / dQ, which represents the ratio of the change in open-circuit voltage V to the change in battery capacity Q during discharge, and a method for inferring the degradation state of a secondary battery based on the peak shape of the differential curve Q-dV / dQ.

[0004] However, since previous non-destructive analysis methods required charging or discharging at low rates, it was time-consuming to infer the degradation state of secondary batteries.

[0005] Existing technical documents

[0006] Patent documents

[0007] Patent Document 1: Publication of Japanese Patent Application No. 2014-511054 Summary of the Invention

[0008] The present invention was made in view of the above-mentioned problems, and its purpose is to shorten the time required to predict the degradation state of a battery using non-destructive analysis methods.

[0009] To address the aforementioned problems, one aspect of the present invention relates to an information processing method executed by a computer, which performs the following steps: instructing a charging device for charging a battery to repeatedly perform a set of charging control comprising a first period of charging and a second period of stopping charging, and allowing the charging device to terminate the charging control when a predetermined amount of charging has been reached; and acquiring operational data representing the battery voltage and charging capacity at the end time of each of the second periods in the charging control. Attached Figure Description

[0010] Figure 1It is a diagram showing the overall structure of the degradation analysis system.

[0011] Figure 2 This is a flowchart illustrating an example of server processing in the process of predicting battery degradation.

[0012] Figure 3 This is a flowchart illustrating an example of the processing of a charging device or adapter during the process of anticipating the state of battery degradation.

[0013] Figure 4 This is a diagram illustrating an example of the charging current supplied to the battery and the battery's open-circuit voltage being detected during maintenance charging.

[0014] Figure 5 This is a graph illustrating an example of the relationship between charging capacity and differential data.

[0015] Figure 6 This is a diagram showing the overall structure of the degradation analysis system in variation example 4.

[0016] Figure 7 This is a diagram showing the overall structure of the degradation analysis system in variation example 5. Detailed Implementation

[0017] (This forms the basis of the understanding in this invention)

[0018] As described above, conventional non-destructive analysis methods, such as the dV / dQ method, are known to analyze the degradation of secondary battery components like the cathode and anode without damaging the battery, as described in Patent Document 1, etc. However, these methods involve charging and discharging the secondary battery at extremely low rates for tens of hours to allow a sufficient change in the open-circuit voltage. Therefore, it is difficult to adequately predict the degradation state of the secondary battery using these conventional non-destructive analysis methods without ceasing its daily use.

[0019] Furthermore, if the battery is charged and discharged at a high rate, differences in the amount of ions and electrons supplied through the electrolyte arise between the regions near the inlet and outlet of the charging and discharging current in the electrode components and other regions, resulting in uneven chemical reactions. In this case, there is a risk that the open-circuit voltage of the battery cannot be obtained with high precision. Therefore, in conventional non-destructive analysis methods, it is necessary to charge and discharge at the lowest possible rate to ensure a uniform distribution of ions and electrons in the electrode components, thereby obtaining the open-circuit voltage of the battery with high precision while suppressing uneven chemical reactions.

[0020] To avoid this problem, the inventors conducted in-depth research and came up with the following technical solution.

[0021] One aspect of the present invention relates to an information processing method executed by a computer, which performs the following steps: instructing a charging device for charging a battery to repeatedly perform a set of charging control comprising a first period of charging and a second period of stopping charging, and having the charging device terminate the charging control when a predetermined amount of charging is reached; and acquiring operating data of the battery voltage and charging capacity at the end time of each second period in the charging control.

[0022] According to this configuration, the charging device performs a set of charging control procedures, consisting of a first period of charging and a second period of stopping charging, until the charge level reaches a predetermined amount. Furthermore, it acquires operational data indicating the battery voltage and charging capacity at the end time of each second period in the charging control.

[0023] Therefore, according to this configuration, even if uneven chemical reactions occur inside the battery during charging in the first period, such unevenness can be suppressed by stopping charging in the second period, resulting in highly accurate working data. Thus, according to this configuration, the battery can be charged at a higher rate than before in the first period, and the battery can be charged to the prescribed amount in a shorter period than before. Accordingly, the time required to predict the battery's degradation state using non-destructive analysis methods can be shortened. As a result, for example, according to this configuration, the battery's degradation state can be appropriately predicted using highly accurate working data without interrupting daily battery use.

[0024] Furthermore, in the aforementioned configuration, the second period may be shorter than the first period.

[0025] According to this configuration, by making the battery charging period longer than the battery charging stop period, it is possible to efficiently perform battery charging for estimating the battery's degradation state. That is, charging time can be shortened.

[0026] Furthermore, in the aforementioned configuration, the number of repetitions of the charging control can be set to ensure that the charging amount reaches the specified amount within a specified time.

[0027] According to this configuration, the charging control is repeated a set number of times within a specified time. Therefore, according to this configuration, the same amount of work data as the set number of times can be acquired. Furthermore, since work data for analysis can be acquired within a specified time, charging and work data acquisition can be performed before battery utilization begins.

[0028] Furthermore, in the aforementioned configuration, the first period and the second period can be configured to allow the charge amount to reach the specified amount within a specified time.

[0029] According to this configuration, by repeatedly performing a set set of charging periods including a first set period and a second set period of stopping charging, the charge level can be reached within a specified time. Furthermore, since operational data for analysis can be acquired within the specified time, charging and data acquisition can be performed before battery use begins.

[0030] Furthermore, in the aforementioned configuration, the instruction can be given when the battery can be charged for a period of time or longer.

[0031] According to this configuration, since the instruction is given for a period of time that can ensure the battery is charged for a specified time or more, it is possible to avoid the battery being undercharged when it is first used.

[0032] Furthermore, in the aforementioned configuration, the differential data of the voltage relative to the charging capacity can be calculated using the operating data, and the degradation state of the battery can be inferred by analyzing the peak values ​​in the differential data.

[0033] Based on this configuration, by analyzing the peak value in the differential data of voltage relative to charging capacity calculated using working data, the time required to predict the battery's degradation state can be shortened.

[0034] Furthermore, in the aforementioned configuration, the peak values ​​in the differential data may include at least one of a first peak value corresponding to the positive electrode of the battery and a second peak value corresponding to the negative electrode of the battery. When inferring the degradation state of the battery, the degradation state of at least one of the positive and negative electrodes of the battery is inferred by analyzing at least one of the first peak value and the second peak value.

[0035] According to this configuration, since at least one of the first peak corresponding to the positive electrode and the second peak corresponding to the negative electrode in the differential data appears to an analyzable extent, it is possible to infer the degradation state of at least one of the positive and negative electrodes of the battery while shortening the time required to infer the degradation state of at least one of the positive and negative electrodes of the battery.

[0036] Furthermore, in the aforementioned configuration, the number of repetitions of the charging control can be set such that the number of repetitions during the period when the charging capacity is within a first range is greater than the number of repetitions during the period when the charging capacity is outside the first range.

[0037] According to this configuration, the number of repetitions of the charging control during the period when the charging capacity is within the first range is greater than the number of repetitions of the charging control during the period when the charging capacity is outside the first range. Therefore, with this configuration, more working data representing the charging capacity within the first range can be acquired than working data representing the charging capacity outside the first range. Thus, the accuracy of the prediction of the deterioration state can be maintained or improved. Furthermore, since the number of times or the duration of the aforementioned charging stop outside the first range is relatively reduced, the time required to reach the specified charging amount can be shortened while ensuring the working data required for analysis within the first range is maintained. Additionally, outside the first range, the aforementioned charging control can be performed intermittently and repeatedly, or the repetition of the charging control can be stopped and charging can continue.

[0038] Furthermore, in the aforementioned configuration, the charging current in the charging control can be set such that the charging current during a period when the charging capacity is within a first range is less than the charging current during a period when the charging capacity is outside the first range.

[0039] According to this configuration, the charging current during the period when the charging capacity is within a first range is set to be less than the charging current during the period when the charging capacity is outside the first range. Accordingly, the increase in charging capacity during the period when the charging capacity is within the first range is less than the increase in charging capacity during the period when the charging capacity is outside the first range. Therefore, the number of repetitions of the charging control during the period when the charging capacity is within the first range is greater than the number of repetitions of the charging control during the period when the charging capacity is outside the first range. As a result, according to this configuration, more working data representing the charging capacity within the first range can be obtained than working data representing the charging capacity outside the first range. Therefore, the accuracy of the prediction of the degradation state can be maintained or improved. Furthermore, when the charging capacity is within the first range, compared to when the charging capacity is outside the first range, uneven chemical reactions occurring inside the battery during the first period can be suppressed. Furthermore, since the charging rate is suppressed to a lower level, degradation caused by charging can be suppressed.

[0040] Furthermore, in the aforementioned configuration, the second period can be set such that the second period of the charging capacity within the first range is longer than the second period of the charging capacity outside the first range.

[0041] According to this configuration, the second period during which the charging capacity is within the first range is set to be longer than the second period during which the charging capacity is outside the first range. Therefore, according to this configuration, during the period of the charging capacity within the first range, it is possible to acquire working data that reduces the inhomogeneity of chemical reactions occurring inside the battery during the first period. In other words, compared to the period when the charging capacity is outside the first range, the effect of this inhomogeneity in the acquired working data can be suppressed. Accordingly, according to this configuration, it is possible to acquire working data suitable for predicting the degradation state. In other words, it is possible to improve the accuracy of predicting the degradation state using the working data.

[0042] Furthermore, in the aforementioned configuration, the first range may be the range of the charging capacity in which a peak occurs in the differential data of the voltage relative to the charging capacity calculated using the operating data.

[0043] According to this configuration, the first range is the range of charging capacities where a peak occurs in the differential data representing the change in voltage relative to the change in charging capacity, calculated using the operating data. Therefore, according to this configuration, the differential data calculated using the operating data representing the charging capacity within the first range can include the peak value. Accordingly, this configuration improves the accuracy of inferring the battery's degradation state using analysis employing this peak value.

[0044] Another aspect of the present invention relates to a charging control device for controlling a charging device for charging a battery, comprising: an instruction unit that instructs the charging device to repeatedly perform a set of charging control including a first period of charging and a second period of stopping charging, and to terminate the charging control when the charging amount reaches a predetermined amount; and an acquisition unit that acquires operating data of the battery voltage and charging capacity at the end time of each second period in the charging control.

[0045] According to this configuration, the charging device performs a set of charging control procedures, consisting of a first period of charging and a second period of stopping charging, until the charge level reaches a predetermined amount. Furthermore, it acquires operational data indicating the battery voltage and charging capacity at the end time of each second period in the charging control.

[0046] Therefore, according to this configuration, even if uneven chemical reactions occur inside the battery during charging in the first period, such unevenness can be suppressed by stopping charging in the second period, resulting in highly accurate working data. Thus, according to this configuration, the battery can be charged at a higher rate than before in the first period, and the battery can be charged to the prescribed amount in a shorter period than before. Accordingly, the time required to predict the battery's degradation state using non-destructive analysis methods can be shortened. As a result, for example, according to this configuration, the battery's degradation state can be appropriately predicted using highly accurate working data without interrupting daily battery use.

[0047] Furthermore, in the aforementioned configuration, the charging device includes: a receiving unit for receiving a charging instruction; a charging control unit for repeatedly performing a set of charging control consisting of a first period of charging and a second period of stopping charging according to the charging instruction, and ending the charging control when the charging amount reaches a predetermined amount; and a transmitting unit for transmitting operating data representing the voltage and charging capacity of the battery during the charging control.

[0048] According to this configuration, by sending a charging instruction to the charging device, it is possible to obtain working data from the charging device indicating the battery voltage and charging capacity when repeatedly performing a set of charging control including a first period of charging and a second period of stopping charging.

[0049] Therefore, according to this configuration, even if uneven chemical reactions occur inside the battery during charging in the first period, such unevenness can be suppressed by stopping charging in the second period, resulting in highly accurate working data. Thus, according to this configuration, the battery can be charged at a higher rate than before in the first period, and the battery can be charged to the prescribed amount in a shorter period than before. Accordingly, the time required to predict the battery's degradation state using non-destructive analysis methods can be shortened. As a result, for example, according to this configuration, the battery's degradation state can be appropriately predicted using highly accurate working data without interrupting daily battery use.

[0050] (Implementation Method)

[0051] Hereinafter, the degradation analysis system according to embodiments of the present invention will be described with reference to the accompanying drawings. Figure 1 This is a diagram showing the overall structure of the degradation analysis system 1. The degradation analysis system 1 is a system that analyzes the degradation state of the battery 45 installed in the vehicle 4, which is a vehicle commonly used for delivering goods, company use, and commuting.

[0052] Specifically, such as Figure 1 As shown, the degradation analysis system 1 includes a vehicle 4, an adapter 3, a charging device 5, and a server 2 (charging control device).

[0053] Vehicle 4 includes battery 45. Battery 45 is a rechargeable secondary battery, mainly composed of a positive electrode, a negative electrode, an electrolyte, and a separator. Vehicle 4 operates using the power supplied to battery 45. Battery 45 is connected to charging device 5 via adapter 3. Battery 45 supplies the charged power to various parts of vehicle 4.

[0054] Adapter 3 is positioned between battery 45 and charging device 5. Adapter 3 communicates with server 2 and charging device 5, causing charging device 5 to operate according to control information received from server 2. Specifically, adapter 3 includes a communication unit 32, a power adapter 33, a sensor 31, and a control unit 30.

[0055] The communication unit 32 includes a communication interface circuit for communicating with external devices such as the server 2 and the charging device 5 via a network 7 such as a LAN (Local Area Network) or the Internet. The communication unit 32 outputs information received from external devices to the control unit 30 and sends information input from the control unit 30 to external devices.

[0056] The power adapter 33 is connected to the power supply unit 51 of the charging device 5 and the battery 45 of the vehicle 4, and has an internal power line (not shown) connecting the power supply unit 51 and the battery 45. Furthermore, the power adapter 33 is connected to the control unit 30 and the sensor 31, and has an internal communication line (not shown) connecting the control unit 30 and the sensor 31.

[0057] Sensor 31 includes, for example, a current sensor and a voltage sensor. Sensor 31 is connected to the power lines provided inside the power adapter 33 and detects the charging current supplied from the charging device 5 to the battery 45 and the open-circuit voltage (battery voltage) between the positive and negative terminals of the battery 45.

[0058] The control unit 30 includes a microcomputer equipped with a CPU (Central Processing Unit) and memory. The control unit 30 controls the various parts of the adapter 3 by executing a control program stored in the memory.

[0059] For example, if the communication unit 32 receives control information from the server 2 for controlling the charging device 5, the control unit 30 transmits the received control information to the charging device 5 via the communication unit 32. Accordingly, the control unit 30 operates the charging device 5 according to the control information received from the server 2. Furthermore, the control unit 30 calculates the charging capacity of the battery 45 based on the detection results of the sensor 31. The charging capacity of the battery 45 refers to the amount of electricity charged into the battery 45.

[0060] The charging device 5 controls the charging of the battery 45 according to the control information received from the server 2 via the adapter 3. Specifically, the charging device 5 includes a communication unit 52 (transmitting and receiving units), a power supply unit 51, and a control unit 50 (charging control unit).

[0061] The communication unit 52 includes a communication interface circuit for communicating with external devices such as the server 2 and the adapter 3 via the network 7. The communication unit 52 outputs information received from external devices to the control unit 50, and sends information input from the control unit 50 to external devices.

[0062] The power supply unit 51 includes an AC / DC converter and / or a DC / DC converter. Under the control of the control unit 50, the power supply unit 51 converts the power supplied from the commercial power source into specified AC or DC power, and supplies the converted power to the battery 45 of the vehicle 4 to charge the battery 45.

[0063] The control unit 50 includes a microcomputer equipped with a CPU (Central Processing Unit) and memory. The control unit 50 controls each part of the charging device 5 by executing a control program stored in the memory.

[0064] For example, if the communication unit 52 receives control information indicating a charging instruction for the battery 45, the control unit 50 controls the power supply unit 51 to start, stop, and stop supplying power to the battery 45 according to the charging instruction shown in the control information, and adjusts the amount of power supplied to the battery 45. Accordingly, the control unit 50 starts, stops, and stops charging the battery 45 according to the charging instruction shown in the control information, and adjusts the amount of charging.

[0065] Server 2 communicates with adapter 3 to control charging device 5 to charge battery 45 of vehicle 4. Specifically, server 2 includes storage unit 24, communication unit 22, and control unit 20.

[0066] The storage unit 24 includes storage devices such as an SSD (Solid State Drive) and / or HDD (Hard Disk Drive) that store a predetermined control program, and stores various information related to the charging of the battery 45. The information related to the charging of the battery 45 includes, for example, information indicating the materials of the components constituting the positive electrode, negative electrode, and electrolyte of the battery 45.

[0067] The communication unit 22 includes a communication interface circuit for communicating with external devices such as the adapter 3 and the charging device 5 via the network 7. The communication unit 22 outputs information received from the external device to the control unit 20, and sends information input from the control unit 20 to the external device.

[0068] The control unit 20 includes a microcomputer (computer) equipped with a CPU, etc. The control unit 20 controls the various parts of the server 2 by executing the control program stored in the storage unit 24.

[0069] For example, the control unit 20 functions as the instruction unit 200 and the acquisition unit 201 by executing the control program stored in the storage unit 24.

[0070] The instruction unit 200 instructs the charging device 5 to repeatedly perform a set of charging control consisting of a first period of charging and a second period of stopping charging, and terminates the charging control when the charging amount reaches a predetermined amount. The acquisition unit 201 acquires operating data indicating the voltage and charging capacity of the battery 45 at the end time of each second period in the charging control.

[0071] The above description illustrates an example of communication between the communication unit 32 of the adapter 3, the communication unit 52 of the charging device 5, and the communication unit 22 of the server 2 via the network 7. However, this is not a limitation; the communication units 32 of the adapter 3, 52 of the charging device 5, and 22 of the server 2 may also communicate directly with each other without using the network 7, for example, according to communication standards such as Bluetooth (registered trademark).

[0072] The following describes the operation of the degradation analysis system 1 in predicting the degradation state of battery 45. Figure 2 This is a flowchart illustrating an example of server 2's processing in the action of speculating on the deterioration state of battery 45. Figure 3 This is a flowchart illustrating an example of the processing of the charging device 5 or adapter 3 during the operation of predicting the deterioration state of the battery 45.

[0073] Assume the user uses a charging cable (not shown) and connects to the power supply adapter 33 via adapter 3. Figure 1 After connecting the battery 45 of vehicle 4 to the charging device 5, a prescribed operation to begin charging the battery 45 is performed. This prescribed operation can be performed on any of the charging device 5, vehicle 4, adapter 3, and server 2. Alternatively, it can be performed on a portable terminal such as a user's smartphone. Upon performing this prescribed operation, information indicating the start of charging of the battery 45 is sent to server 2. Alternatively, information indicating the start of charging can be sent to server 2 based on a charging plan, instead of the prescribed operation. Furthermore, if server 2 manages the charging plan, it can also determine whether charging has started.

[0074] If the communication unit 22 of server 2 receives information indicating an instruction to start charging battery 45, then the instruction unit 200... Figure 2The system determines whether it is time to perform maintenance charging (step S1). Maintenance charging is a charging operation performed on battery 45 to assess the degradation state of battery 45.

[0075] For example, in step S1, if a predetermined period (e.g., 3 months) has elapsed since the last maintenance charging, the indicator unit 200 determines that it is time to perform maintenance charging (yes in step S1). On the other hand, if no predetermined period has elapsed since the last maintenance charging, the indicator unit 200 determines that it is not time to perform maintenance charging (no in step S1).

[0076] Furthermore, when vehicle 4 is a company vehicle or a delivery vehicle for goods, the scheduled date and time for the next use of vehicle 4 are sometimes predetermined. In this case, information indicating the scheduled date and time for the next use of vehicle 4 can be stored in advance in the storage unit 24 of server 2. Then, in step S1, the instruction unit 200 determines whether it is time to perform maintenance charging based on whether a specified time or more can be ensured before the scheduled date and time for the next use of vehicle 4. The specified time can be, for example, a time longer than the time required for maintenance charging (e.g., 10 hours).

[0077] In step S1, if the indication unit 200 determines that it is not the right time to perform maintenance charging (no in step S1), it sends control information indicating normal charging to the adapter 3 through the communication unit 22 (step S6).

[0078] like Figure 3 As shown, in adapter 3, if communication unit 32 receives control information indicating normal charging sent in step S6 (no in step S11), control unit 30 controls communication unit 32 to send the control information to charging device 5. In charging device 5, if communication unit 52 receives the control information, control unit 50 performs normal charging according to the charging instruction shown in the control information (step S19). That is, control unit 50 instructs power supply unit 51 to convert the power supplied from commercial power supply into specified AC or DC power, and supplies the converted power to battery 45 of vehicle 4.

[0079] On the other hand, such as Figure 2As shown, in step S1, if the indication unit 200 determines that it is time to perform maintenance charging (yes in step S1), it sends control information indicating a maintenance charging instruction to the adapter 3 via the communication unit 22 (step S2). The maintenance charging instruction refers to an instruction to repeatedly perform charging control by charging the battery 45 with a specified current value in a first period and then stopping charging in a second period, and to end the charging control when the specified amount of charge is reached.

[0080] like Figure 3 As shown, in adapter 3, if communication unit 32 receives control information indicating a maintenance charging instruction sent in step S2 (yes in step S11), control unit 30 controls communication unit 32 to send the control information to charging device 5. Furthermore, control unit 30 controls sensor 31 to periodically detect the charging current supplied to battery 45 and the open-circuit voltage of battery 45. Additionally, control unit 30 periodically calculates the charging capacity of battery 45 based on the detection results of sensor 31.

[0081] On the other hand, in the charging device 5, if the communication unit 52 receives control information indicating a maintenance charging instruction, the control unit 50 starts the charging operation of the battery 45 according to the maintenance charging instruction shown in the control information (step S12). Specifically, in step S12, the control unit 50 controls the power supply unit 51 to supply a charging current of a predetermined current value to the battery 45.

[0082] After the charging operation of the battery 45 begins in step S12, the control unit 50 continues the charging operation for a period up to the first period T1 (if not in step S13). Furthermore, if the first period T1 has elapsed after the start of the charging operation (if yes in step S13), the control unit 50 stops the charging operation (step S14). Specifically, in step S14, the control unit 50 controls the power supply unit 51 to stop supplying charging current to the battery 45.

[0083] After the charging operation stops in step S14, the control unit 50 remains in standby mode for the period up to the second period T2 (if not in step S15). If the second period T2 has elapsed after the charging operation stops in step S14 (if yes in step S15), the control unit 50 sends a message indicating the end of the second period T2 to the adapter 3. In the adapter 3, if the communication unit 32 receives the message indicating the end of the second period T2, the control unit 30 records the operating data, which includes the open-circuit voltage of the battery 45 detected by the sensor 31 at the time of reception and the calculated charging capacity of the battery 45 at the time of reception, in its memory in correspondence with the date and time of reception (step S16). On the other hand, the control unit 50 determines whether the charging amount has reached a predetermined amount (step S17). Here, the charging amount represents the amount of electricity supplied to the battery 45.

[0084] Specifically, in step S17, the control unit 50 calculates the cumulative value of the charging current supplied to the battery 45 as the charging amount, and determines whether the calculated charging amount is above a predetermined amount. In step S17, if the control unit 50 determines that the charging amount has reached the predetermined amount (yes in step S17), it sends a message to the adapter 3 indicating that the maintenance charging has ended.

[0085] In adapter 3, if the communication unit 32 receives information indicating the end of maintenance charging, the control unit 30 controls the communication unit 32 to send the working data stored in the memory and information indicating the date and time corresponding to the working data to the server 2 (step S18).

[0086] On the other hand, in step S17, if the control unit 50 determines that the charging amount has not reached the predetermined amount (no in step S17), it repeatedly performs the processing from step S12 onwards. Accordingly, the control unit 50 repeatedly performs a set of charging control including the charging operation during the first period T1 and the charging stop during the second period T2.

[0087] like Figure 2 As shown, in server 2, if communication unit 22 receives information representing work data and date and time after step S2, acquisition unit 201 sequentially acquires the work data received by communication unit 22 starting from the data corresponding to the information representing the earlier date and time (step S3).

[0088] Next, the control unit 20 calculates the differential data of the open-circuit voltage relative to the charging capacity using the operating data obtained in step S3 (step S4). Specifically, the control unit 20 calculates the differential data using the following formula (1).

[0089] dV / dQ(n)=(V n -V n-1 ) / (Q n -Qn-1 (1)

[0090] In equation (1), dV / dQ(n) represents the differential data of date and time n. n Q represents the open-circuit voltage contained in the working data corresponding to date and time n. n This represents the charging capacity included in the working data corresponding to date and time n. V n-1 This represents the open-circuit voltage contained in the working data corresponding to date and time n-1, which was obtained before the working data corresponding to date and time n. Q n-1 This represents the charging capacity contained in the working data corresponding to date and time n-1, which was previously acquired. Furthermore, to suppress noise components in the aforementioned differential data dV / dQ(n), processing such as addition arithmetic averaging of differential data dV / dQ(n) from similar dates and times can be implemented.

[0091] Next, the control unit 20 infers the degradation state of the battery 45 by analyzing the peak values ​​in the differential data calculated in step S4 (step S5), and then ends the process. Details of step S5 will be explained later.

[0092] In addition, after sending control information indicating a maintenance charging instruction to the adapter 3 in step S2, the control unit 20 is in a waiting state until it receives the working data. However, instead, the control unit 20 may also send control information indicating execution instructions for steps S12 and S14 to the charging device 5 through the adapter 3 to perform judgment processing for steps S13, S15, and S17.

[0093] In this case, in order for the control unit 20 to perform the judgment process of step S17, the control unit 30 of the adapter 3 can send the information indicating the charging current detected by the sensor 31 to the server 2 through the communication unit 32 after the communication unit 32 receives the control information indicating the execution instruction of step S12.

[0094] (Specific examples of charging current and open-circuit voltage)

[0095] Next, a specific example will be described of the charging current supplied to battery 45 and the open-circuit voltage of the battery that are detected during maintenance charging. In this specific example, it is assumed that maintenance charging begins from a state where battery 45 is empty. Figure 4 This is a diagram showing an example of the charging current I supplied to battery 45 and the open-circuit voltage V of battery 45 being detected during maintenance charging.

[0096] exist Figure 4The upper part of Figure G1 shows the time series variation of the charging current I during maintenance charging, with the horizontal axis representing time and the vertical axis representing the charging current I. Figure 4 The lower part of the figure G2 is a graph showing the time series change of the open circuit voltage V of the battery 45 detected by the sensor 31 during maintenance charging. The horizontal axis represents time and the vertical axis represents the open circuit voltage V.

[0097] If maintenance charging begins, as shown in Figure G1, during the first period T1, a charging current I with a current value Ic is supplied to battery 45. Accordingly, as shown in Figure G2, the open-circuit voltage V of battery 45 detected by sensor 31 gradually increases.

[0098] If the first period T1 passes, the charging operation stops during the second period T2, as shown in Figure G1, and the charging current I is not supplied to the battery 45. Accordingly, the unevenness of the chemical reaction occurring inside the battery 45 during the first period is gradually suppressed, as shown in Figure G2, and the open-circuit voltage V of the battery 45 detected by the sensor 31 gradually decreases. Furthermore, at the end of the second period T2, at time Ts, the operating data indicating the open-circuit voltage V detected by the sensor 31 and the charging capacity of the battery 45 calculated by the control unit 30 are sent to the server 2.

[0099] Therefore, during maintenance charging, a set of charging control consisting of a first period T1 and a second period T2 is repeatedly performed. Then, maintenance charging ends at a time Tm when the amount of charge supplied from the charging device 5 to the battery 45 reaches a predetermined amount. In addition, the amount of charge supplied from the charging device 5 to the battery 45 is calculated by the following formula (2).

[0100] Pc=Ic×T1×m (2)

[0101] In equation (2), Pc represents the amount of charge supplied from the charging device 5 to the battery 45, and m represents the number of times the first period T1 is charged up to the time when the amount of charge is calculated.

[0102] In addition, Figure 4 In this example, the second period T2 is determined to be shorter than the first period T1. That is, in this specific example, by making the period during which the battery 45 is charged longer than the period during which the charging of the battery 45 stops, maintenance charging for predicting the degradation state of the battery 45 can be carried out efficiently. However, this is not a limitation; the second period T2 can also be determined to be longer than the first period T1 if a longer charging time can be ensured.

[0103] In addition, Figure 3In this example, to enable maintenance charging to bring battery 45 to a fully charged state within a specified time (e.g., approximately 7 hours), the charging current I value Ic, the first period T1, and the second period T2 are set. Specifically, the charging current I value Ic is set to charge battery 45 to 0.2C within 5 hours. The first period T1 is set to 3 minutes, and the second period T2 is set to 1 minute. However, the charging current I value Ic and the first period T1 are not limited to these values; they can be set to bring the charge level in the first period T1 to 1% of the state of charge (SOC) of battery 45. In other words, maintenance charging is performed approximately 100 times, starting from an empty state and continuing until battery 45 reaches a fully charged state.

[0104] Alternatively, the number of repetitions of the charging control can be appropriately set so that the charging amount reaches a predetermined amount within a specified period (e.g., 8 hours) from the start of maintenance charging. Furthermore, the number of repetitions of the charging control (e.g., 100 times) can be set so that the charging amount reaches a predetermined amount within a specified period (e.g., 8 hours) from the start of maintenance charging, and the first period T1 and the second period T2 can be appropriately set based on this number of repetitions.

[0105] Furthermore, if it is difficult to adjust the number of charging control repetitions, the first period T1, and the second period T2 in a way that ensures the charge amount reaches the specified amount over a predetermined period from the start of maintenance charging, the current value Ic of the charging current I in the first period T1 can also be adjusted. However, the higher the current value Ic, the greater the unevenness of the chemical reaction occurring inside the battery during the first period T1. Therefore, the higher the current value Ic, the longer the second period T2 can be adjusted.

[0106] (A hypothetical example of the degradation state of battery 45)

[0107] Next, the steps in S5 will be explained. Figure 2 ) is a specific example of the inferred degradation state of battery 45. Figure 5 This indicates the charging capacity Q. n Figure G3 shows an example of the relationship between the differential data dV / dQ(n). Figure 5 The vertical axis represents the vertical axis in step S4 ( Figure 2 The differential data dV / dQ(n) of the calculated date and time n. Figure 5 The horizontal axis represents the battery charging capacity Q at that date and time n (45). n In step S5 ( Figure 2 ), control unit 20 Figure 5As shown, the charging capacity Q of battery 45 is generated. n Plot G3 shows the relationship between the differential data dV / dQ(n).

[0108] In the generated graph G3, the control unit 20 sets the inflection points N1, P1, N2, and P2 where the differential data dV / dQ(n) changes from an increasing trend to a decreasing trend as the peak values ​​in the differential data dV / dQ(n).

[0109] Furthermore, each peak value can be identified as the open-circuit voltage of either the positive or negative electrode based on experimental values ​​and the materials of the components constituting the positive and negative electrodes of battery 45. Figure 5 In the example, the inflection points N1, P1, N2, and P2, which are the peak values ​​appearing in the differential data dV / dQ(n), correspond to the open-circuit voltages of the negative, positive, negative, and positive terminals, respectively.

[0110] Then, the control unit 20 sets the charging capacity Q corresponding to the peak values, i.e., the inflection points P1 and P2, of the open-circuit voltage corresponding to the positive electrode. n The differential data dV / dQ(n) are analyzed and processed to infer the degradation state of the positive electrode's capacity. Furthermore, the control unit 20 calculates the charging capacity Q corresponding to the peak values, i.e., inflection points N1 and N2, of the open-circuit voltage corresponding to the negative electrode. n The differential data dV / dQ(n) are analyzed and processed to infer the degradation state of the negative electrode capacity.

[0111] Furthermore, the control unit 20 measures the charging capacity Q corresponding to the inflection points N1, P1, N2, and P2. n The differential data dV / dQ(n) are analyzed and processed to infer the reaction equilibrium between the positive and negative electrodes.

[0112] Furthermore, depending on the materials of the components constituting the positive and negative electrodes of the battery 45, the differential data dV / dQ(n) may sometimes only show a peak value corresponding to the open-circuit voltage of either the positive or negative electrode. In this case, the control unit 20 infers the capacity degradation state of that electrode by analyzing the peak value corresponding to the open-circuit voltage of that electrode.

[0113] (Variation Example 1)

[0114] In the above embodiment, an example of detecting the open-circuit voltage between the positive and negative terminals of battery 45 during maintenance charging was described. However, in a laboratory setting where battery 45 can be disassembled, sensor 31 can also be used. Figure 1The open-circuit voltage of the positive terminal and the open-circuit voltage of the negative terminal are detected separately. Correspondingly, the adapter 3 can send operating data to the server 2, representing the detected open-circuit voltages of the positive and negative terminals and the charging capacity of the battery 45.

[0115] In this case, in step S4 ( Figure 2 The control unit 20 can also utilize step S3 ( Figure 2 The obtained working data are used to separately calculate the differential data of the open circuit voltage of the positive electrode relative to the charging capacity (hereinafter referred to as the positive electrode differential data) and the differential data of the open circuit voltage of the negative electrode relative to the charging capacity (hereinafter referred to as the negative electrode differential data).

[0116] Furthermore, the control unit 20 can also generate a charging capacity Q representing the battery 45. n A graph showing the relationship between the cathode differential data and the peak values ​​appearing in the cathode differential data in the graph is used to infer the capacity degradation of the cathode.

[0117] Similarly, the control unit 20 generates a charging capacity Q representing the battery 45. n A graph showing the relationship between the negative electrode differential data and the peak values ​​appearing in the negative electrode differential data in the graph is analyzed to infer the capacity degradation of the negative electrode.

[0118] Alternatively, in the same manner, sensor 31 may detect only one of the open-circuit voltages of the positive and negative electrodes and infer only the capacity degradation of that one electrode.

[0119] (Variation Example 2)

[0120] In the above embodiment, an example was described in which, during maintenance charging, a set of charging and stopping operations, including the first period T1 and the second period T2, were repeatedly performed without changing the current value Ic of the charging current I, the first period T1, and the second period T2. However, alternatively, the charging capacity Q of the battery 45 could also be considered. n The charging control is repeatedly performed by changing one or more of the following: the current value Ic of the charging current I, the first period T1, and the second period T2.

[0121] For example, assuming that the degradation state of battery 45 can be predicted in advance, such as... Figure 5 The charging capacity Q of the battery 45 shown is... n The relationship between the differential data dV / dQ(n) of the battery 45 and the capacity range (e.g., 0.5Ah-0.8Ah) in the differential data dV / dQ(n) of the battery 45 where the peak value (e.g., N1) occurs can be determined as the first range.

[0122] First, during the period when the charging capacity of the battery 45 calculated by the control unit 30 is within a first range, either the current value Ic of the charging current I and the first period T1 can be changed for the charging capacity within the first range and for the period outside the first range. Accordingly, compared to the period outside the first range of the charging capacity, charging control can be performed more times, increasing the amount of working data obtained, thereby improving the accuracy of the peak values ​​appearing in the differential data dV / dQ of the battery 45.

[0123] Specifically, during the period when the charging capacity is within a first range, the current value Ic of the charging current I can be set to be less than the current value during the period when the charging capacity is outside the first range. Alternatively, during the period when the charging capacity is within the first range, the first period T1 can be set to be shorter than the first period during the period when the charging capacity is outside the first range. By doing so, the amount of charge received during the first period T1 can be reduced during the period when the charging capacity is within the first range, thereby increasing the number of charging control repetitions when the charging capacity is within the first range.

[0124] Second, during the period when the charging capacity is within the first range, the second period T2 can be set to be longer than the second period during the period when the charging capacity is outside the first range. Accordingly, the accuracy of the peak values ​​appearing in the differential data dV / dQ(n) of the battery 45 can be improved. Uneven chemical reactions occurring inside the battery 45 during the charging process in the first period T1 can be suppressed.

[0125] Furthermore, in the first or second case described above, during the period when the charging capacity is outside the first range, the second period T2 can be made shorter (it can be set to 0). Additionally, during the period when the charging capacity is outside the first range, the current value Ic of the charging current I can be set to be greater than the current value during the period when the charging capacity is within the first range. Accordingly, the time required for maintenance charging can be shortened.

[0126] Alternatively, one or more of the above-mentioned methods for changing the charging current I value Ic, the first period T1, and the second period T2 can be combined.

[0127] (Variation Example 3)

[0128] In the above embodiments, utilizing Figure 4 This example illustrates starting maintenance charging from a state where battery 45 is empty. However, maintenance charging can also begin when battery 45 is not empty and end when the charge level reaches a predetermined amount. Similarly, maintenance charging can be started from a state where battery 45 is empty and ended when the charge level reaches a predetermined amount at other opportunities.

[0129] As mentioned above, maintenance charging can also be performed in multiple opportunities, in step S5 ( Figure 2 The degradation state of battery 45 is inferred by selecting an appropriate peak from the recurring peaks in the differential data dV / dQ(n) calculated from the working data obtained from the multiple opportunities, or by averaging the analysis results of the recurring peaks.

[0130] (Variation Example 4)

[0131] In the above-described embodiments and variations, an example of inferring the degradation state of battery 45 in server 2 was described. Alternatively, server 2 may be omitted, and the degradation analysis system may be configured to infer the degradation state of battery 45 in adapter.

[0132] Figure 6 This is a diagram showing the overall structure of system 1a in the degradation analysis of variant example 4. Specifically, as shown... Figure 6 As shown, the adapter 3a (charging control device) of the degradation analysis system 1a in this modified example includes a storage unit 24 (…). Figure 1 Similar to the storage unit 34. The control unit 30a of the adapter 3a is similar to the control unit 20 of the server 2. Figure 1 It functions similarly to the instruction unit 200 and the acquisition unit 201. Figure 1 The similar indicator unit 300 and acquisition unit 301 also function. In addition, in this modified example, the communication unit 32 of the adapter 3a and the communication unit 52 of the charging device 5 can also communicate directly without going through the network 7.

[0133] (Variation Example 5)

[0134] Unlike the above-described embodiments and variations, this system does not include server 2 and adapters 3 and 3a. Instead, the degradation analysis system is configured to predict the degradation state of battery 45 in a vehicle.

[0135] Figure 7 This is a diagram showing the overall structure of system 1b in the degradation analysis of variant example 5. Specifically, as shown... Figure 7 As shown, in the degradation analysis system 1b of this modified example, the vehicle 4b (charging control device) includes a storage unit 24 (… Figure 1 Similar to the storage unit 44; and the power adapter 33, sensor 31, and communication unit 32 of the adapter 3. Figure 1 Similar to power adapter 43, sensor 41, and communication unit 42. Furthermore, vehicle 4b includes a power adapter 3a ( Figure 6The control unit 40b is similar to the control unit 30a, and functions as the indicator unit 400 and the acquisition unit 401, which are similar to the indicator unit 300 and the acquisition unit 301. In addition, in this modification, the communication unit 42 of the vehicle 4b and the communication unit 52 of the charging device 5 can also communicate directly without going through the network 7.

[0136] (Variation Example 6)

[0137] In the above-described embodiments and variations, the charging device 5 may also include a power adapter 33. Figure 1 Similar power adapters and with sensor 31 ( Figure 1 Similar sensors, the control unit 50 of the charging device 5 ( Figure 1 , Figure 6 , Figure 7 The charging capacity of battery 45 is calculated based on the detection results of the sensor. Furthermore, the control unit 50 of the charging device 5 ( Figure 1 , Figure 6 , Figure 7 The operating data representing the detected and calculated open-circuit voltage and charging capacity of battery 45 will be transmitted via the communication unit 52. Figure 1 , Figure 6 , Figure 7 ) sent to the acquisition unit 201 of server 2 ( Figure 1 ), Adapter 3a acquisition unit 301 ( Figure 6 ) and the acquisition unit 401 of vehicle 4b ( Figure 7 ).

[0138] Alternatively, it can be connected to power adapter 33 ( Figure 1 Similar power adapters and sensors 31 Figure 1 Similar sensors are installed in vehicle 4 ( Figure 1 ), 4b Figure 7 ), Adapter 3 ( Figure 1 ), 3a ( Figure 6 Server 2 Figure 1 ) and charging device 5 ( Figure 1 , Figure 6 , Figure 7 The detection result of the sensor is sent to server 2 at any time from any one of the following: Figure 1 ), Adapter 3a ( Figure 6 ) and vehicle 4b ( Figure 7 Additionally, it can also be obtained from the acquisition section 201 of server 2. Figure 1 ), Adapter 3a acquisition unit 301 ( Figure 6 ) and the acquisition unit 401 of vehicle 4b ( Figure 7 The charging capacity of battery 45 is calculated in the computer to obtain working data.

[0139] Industrial availability

[0140] According to the present invention, it is valuable in appropriately predicting the degradation state of a secondary battery through non-destructive analysis methods without stopping its daily use.

Claims

1. An information processing method, executed by a computer, characterized in that... Perform the following steps: The charging device for charging the battery is instructed to repeatedly perform a set of charging control consisting of a first period of charging and a second period of stopping charging, and the charging device is instructed to terminate the charging control when the amount of charge reaches a predetermined amount. Acquire operational data representing the battery voltage and charging capacity at the end time of each of the second periods in the charging control; as well as The degradation state of the battery can be inferred using the aforementioned working data. The second period is set such that the second period of the charging capacity within the first range is longer than the second period of the charging capacity outside the first range.

2. The information processing method according to claim 1, characterized in that, The second period is shorter than the first period.

3. The information processing method according to claim 1 or 2, characterized in that, The number of repetitions of the charging control is set to ensure that the charging amount reaches the specified amount within a specified time.

4. The information processing method according to claim 1 or 2, characterized in that, The first period and the second period are set to allow the charge amount to reach the specified amount within a specified time.

5. The information processing method according to claim 1 or 2, characterized in that, The instruction is given when it is possible to charge the battery for a period of time exceeding the specified time.

6. The information processing method according to claim 1 or 2, characterized in that, The differential data of the voltage relative to the charging capacity is calculated using the working data. The degradation state of the battery can be inferred by analyzing the peak values ​​in the differential data.

7. The information processing method according to claim 6, characterized in that, The peak values ​​in the differential data include at least one of a first peak value corresponding to the positive electrode of the battery and a second peak value corresponding to the negative electrode of the battery. When inferring the degradation state of the battery, the degradation state of at least one of the positive and negative electrodes of the battery is inferred by analyzing at least one of the first peak and the second peak.

8. The information processing method according to claim 1 or 2, characterized in that, The number of repetitions of the charging control is set such that the number of repetitions during the period when the charging capacity is within a first range is greater than the number of repetitions during the period when the charging capacity is outside the first range.

9. The information processing method according to claim 1 or 2, characterized in that, The charging current in the charging control is set such that the charging current during the period when the charging capacity is within a first range is less than the charging current during the period when the charging capacity is outside the first range.

10. The information processing method according to claim 1 or 2, characterized in that, The first range is the range of charging capacities where a peak occurs in the differential data of the voltage relative to the charging capacity calculated using the working data.

11. A charging control device for controlling a charging device for charging a battery, characterized in that... include: The instruction unit instructs the charging device to repeatedly perform a set of charging control consisting of a first period of charging and a second period of stopping charging, and to terminate the charging control when the charging amount reaches a predetermined amount. as well as The acquisition unit acquires operational data representing the battery voltage and charging capacity at the end time of each second period in the charging control, the operational data being used to infer the battery's degradation state. The second period is set such that the second period of the charging capacity within the first range is longer than the second period of the charging capacity outside the first range.

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