Information processing method and charge control device

Abstract

This information processing method, to be executed by a computer, includes: instructing a charging device for charging a battery to repeat charging control, comprising a group of charging for a first period and stopping charging for a second period, and to terminate the charging control when the amount of charge reaches a prescribed amount; and acquiring operation data indicating the voltage and the charging capacity of the battery at the termination point of each second period during the charging control.

Description

[Technical field]

[0001] The present disclosure relates to techniques for analyzing the state of health of a rechargeable battery. [Background technology]

[0002] Conventionally, a non-destructive analysis method called the dV / dQ method is known for analyzing the deterioration of components of a secondary battery, such as a positive electrode and a negative electrode, without destroying the secondary battery. In the non-destructive analysis method, the secondary battery is charged or discharged at an extremely low rate, and the open circuit voltage (OCV (Open Circuit Voltage)) of the secondary battery during the charging or discharging is acquired in time series. Then, the deterioration state of the secondary battery is estimated based on a differential value indicating the amount of change in the open circuit voltage relative to the amount of change in the charge capacity of the secondary battery.

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

[0004] However, conventional non-destructive analysis methods require charging or discharging at a low rate, and therefore take a long time to estimate the deterioration state of a secondary battery. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent Application No. 2014-511054 Summary of the Invention

[0006] The present disclosure has been made in consideration of the above-mentioned problems, and aims to reduce the time required to estimate the degradation state of a battery using a non-destructive analysis method.

[0007] In order to solve the above problem, an information processing method according to one embodiment of the present disclosure is an information processing method executed by a computer, which instructs a charging device that charges a battery to repeat a charging control set of charging for a first period and stopping charging for a second period, and to end the charging control when the charged amount reaches a predetermined amount, and obtains operating data indicating the voltage and charging capacity of the battery for each end point of the second period during the charging control. [Brief description of the drawings]

[0008] [Figure 1] 1 is a diagram showing an overall configuration of a deterioration analysis system. [Diagram 2] 10 is a flowchart showing an example of a process of a server in an operation of estimating a deterioration state of a battery. [Diagram 3] 10 is a flowchart showing an example of processing of a charging device or an adapter in an operation for estimating a deterioration state of a battery. [Figure 4] 4 is a graph showing an example of a charging current supplied to a battery and an open circuit voltage of the battery detected during maintenance charging. [Diagram 5] 11 is a graph showing an example of the relationship between charge capacity and differential data. [Figure 6] FIG. 13 is a diagram showing the overall configuration of a degradation analysis system according to a fourth modified example. [Figure 7] FIG. 13 is a diagram showing an overall configuration of a degradation analysis system according to a fifth modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] (Findings on which this disclosure is based) As described above, a non-destructive analysis method called the dV / dQ method is known for analyzing the deterioration of components of a secondary battery, such as a positive electrode and a negative electrode, without destroying the battery, as described in Patent Document 1 and the like. However, in the conventional non-destructive analysis method, the secondary battery is charged and discharged at an extremely low rate for several tens of hours so that a sufficient change is observed in the open-circuit voltage of the secondary battery. For this reason, it has been difficult to appropriately estimate the deterioration state of a secondary battery using the conventional non-destructive analysis method without stopping the daily operation of the secondary battery.

[0010] In addition, when a battery is charged and discharged at a high rate, the amount of ions and electrons supplied through the electrolyte differs between the area near the inlet and outlet of the charge / discharge current in the electrode component and other areas, causing unevenness in the chemical reaction. In this case, there is a risk that the open-circuit voltage of the battery cannot be obtained accurately. For this reason, in conventional non-destructive analysis methods, it is necessary to charge and discharge at the slowest possible rate to distribute ions and electrons evenly among the electrode component and to obtain the open-circuit voltage of the battery accurately while suppressing unevenness in the chemical reaction.

[0011] The present inventors have conducted extensive research to avoid such problems and have come up with the following disclosed embodiment.

[0012] An information processing method according to one aspect of the present disclosure is an information processing method executed by a computer, which instructs a charging device that charges a battery to repeat a charging control set of charging for a first period and stopping charging for a second period, and to terminate the charging control when the charged amount reaches a predetermined amount, and obtains operating data indicating the voltage and charging capacity of the battery for each end point of the second period during the charging control.

[0013] According to this aspect, the charging device performs charging control of a set of charging for a first period and stopping charging for a second period until the amount of charge reaches a predetermined amount, and acquires operation data indicating the voltage and charge capacity of the battery at each end point of the second period during the charging control.

[0014] Therefore, in this embodiment, even if an unevenness occurs in the chemical reaction inside the battery during charging of the battery in the first period, the unevenness of the chemical reaction can be suppressed by stopping charging for the second period, and accurate operation data can be obtained. Therefore, in this embodiment, the battery is charged at a higher rate than before during the first period, and a predetermined amount of charge can be applied to the battery in a shorter period than before. This shortens the time required to estimate the deterioration state of the battery using a non-destructive analysis method. As a result, for example, this embodiment can appropriately estimate the deterioration state of the battery using accurate operation data without stopping the daily operation of the battery.

[0015] In the above aspect, the second period may be shorter than the first period.

[0016] According to this aspect, the period during which the battery is charged is set longer than the period during which the charging of the battery is stopped, so that the charging of the battery for estimating the deterioration state of the battery can be efficiently performed, i.e., the charging time can be shortened.

[0017] In the above aspect, the number of times the charging control is repeated may be set so that the amount of charge reaches the predetermined amount within a predetermined time.

[0018] According to this aspect, the charging control is repeated a set number of times within a predetermined time. Therefore, this aspect can obtain the same number of operation data as the set number of times. In addition, since the operation data to be used for analysis can be obtained within the predetermined time, charging and obtaining the operation data can be performed before starting to use the battery.

[0019] In the above aspect, the first period and the second period may be set so that the charge amount reaches the predetermined amount within a predetermined time.

[0020] According to this aspect, the charging control of a set of charging for a first period and stopping charging for a second period is repeated to allow the amount of charge to reach a predetermined amount within a predetermined time. Also, since the operation data to be used for analysis can be obtained within the predetermined time, charging and the operation data can be obtained before the battery starts to be used.

[0021] In the above aspect, the instruction may be given when a predetermined time or more can be secured for charging the battery.

[0022] According to this aspect, the instruction is issued when a predetermined amount of time or more can be secured for charging the battery, so that it is possible to avoid the battery becoming insufficiently charged at the start of use.

[0023] In the above aspect, the operational data may be used to calculate differential data of the voltage with respect to the charge capacity, and the degradation state of the battery may be estimated by analyzing a peak in the differential data.

[0024] According to this aspect, it is possible to reduce the time required to estimate the degradation state of the battery by analyzing peaks in differential data of the voltage with respect to the charge capacity calculated using the operation data.

[0025] In the above aspect, the peaks in the differential data include at least one of a first peak corresponding to a positive electrode of the battery and a second peak corresponding to a negative electrode of the battery, and in estimating the degradation state of the battery, the degradation state of at least one of the positive electrode and the negative electrode of the battery may be estimated by analyzing at least one of the first peak and the second peak.

[0026] According to this aspect, at least one of the first peak corresponding to the positive electrode of the battery and the second peak corresponding to the negative electrode of the battery appears in the differential data to an extent that it can be analyzed, so that the deterioration state of at least one of the positive electrode and negative electrode of the battery can be estimated while shortening the time required to estimate the deterioration state of at least one of the positive electrode and negative electrode of the battery.

[0027] In the above aspect, the number of repetitions of the charging control may be set to be greater while the charging capacity is within a first range than while the charging capacity is outside the first range.

[0028] According to this aspect, the number of repetitions of the charging control is greater while the charging capacity is within the first range than while the charging capacity is outside the first range. As a result, this aspect can obtain more operation data indicating the charging capacity within the first range than operation data indicating the charging capacity outside the first range. Therefore, the accuracy of the estimation of the degradation state can be maintained or improved. In addition, since the number of times or time of the charging stop outside the first range is relatively reduced, the time until the charging amount reaches a predetermined amount can be shortened while securing the operation data required for analysis within the first range. In addition, outside the first range, the charging control may be intermittently repeated, or the repetition of the charging control may be stopped and charging may be continued.

[0029] In the above aspect, the charging current in the charging control may be set to be smaller while the charging capacity is within a first range than while the charging capacity is outside the first range.

[0030] According to this aspect, the charging current is set smaller while the charge capacity is within the first range than while the charge capacity is outside the first range. As a result, the degree of increase in the charge capacity during charging in the first period is smaller while the charge capacity is within the first range than while the charge capacity is outside the first range. Therefore, the number of repetitions of the charge control is greater while the charge capacity is within the first range than while the charge capacity is outside the first range. As a result, this aspect can obtain more operation data indicating a charge capacity within the first range than operation data indicating a charge capacity outside the first range. Therefore, the accuracy of the estimation of the degradation state can be maintained or improved. In addition, while the charge capacity is within the first range, the occurrence of unevenness in the chemical reaction occurring inside the battery during the first period can be suppressed more than while the charge capacity is outside the first range. In addition, since the charge rate is kept low, deterioration due to charging can be suppressed.

[0031] In the above aspect, the second period may be set to be longer while the charge capacity is within the first range than while the charge capacity is outside the first range.

[0032] According to this aspect, the second period is set longer while the charge capacity is within the first range than while the charge capacity is outside the first range. Therefore, this aspect can acquire operation data in a state in which the unevenness of the chemical reaction occurring inside the battery during the first period is reduced while the charge capacity is within the first range. In other words, the influence of the unevenness in the acquired operation data can be suppressed more than while the charge capacity is outside the first range. As a result, this aspect can acquire operation data suitable for estimating the degradation state. In other words, the accuracy of estimating the degradation state using the operation data can be improved.

[0033] In the above aspect, the first range may be a range of the charge capacity in which a peak appears in differential data, calculated using the operation data, that indicates an amount of change in the voltage relative to an amount of change in the charge capacity.

[0034] According to this aspect, the first range is a range of charge capacity where a peak appears in differential data that indicates the amount of change in voltage relative to the amount of change in charge capacity, calculated using the operation data. Therefore, this aspect can include a peak in differential data calculated using operation data that indicates a charge capacity within the first range. This can improve the accuracy of estimating the deterioration state of the battery using the analysis of the peak.

[0035] A charging control device according to another aspect of the present disclosure is a charging control device that controls a charging device that charges a battery, and includes an instruction unit that instructs the charging device to repeat a charging control set of charging for a first period and stopping charging for a second period, and to terminate the charging control when the charged amount reaches a predetermined amount, and an acquisition unit that acquires operating data indicating the voltage and charging capacity of the battery for each end point of the second period during the charging control.

[0036] According to this aspect, the charging device performs charging control of a set of charging for a first period and stopping charging for a second period until the amount of charge reaches a predetermined amount, and acquires operation data indicating the voltage and charge capacity of the battery at each end point of the second period during the charging control.

[0037] Therefore, in this embodiment, even if an unevenness occurs in the chemical reaction inside the battery during charging of the battery in the first period, the unevenness of the chemical reaction can be suppressed by stopping charging for the second period, and accurate operation data can be obtained. Therefore, in this embodiment, the battery is charged at a higher rate than before during the first period, and a predetermined amount of charge can be applied to the battery in a shorter period than before. This shortens the time required to estimate the deterioration state of the battery using a non-destructive analysis method. As a result, for example, this embodiment can appropriately estimate the deterioration state of the battery using accurate operation data without stopping the daily operation of the battery.

[0038] In the above aspect, the charging device is A receiving unit that receives a charging instruction; According to the charging instructions, Repeating a charging control set of a first period of charging and a second period of stopping charging, a charge control unit that terminates the charge control when a charge amount reaches a predetermined amount; a transmitter that transmits operation data indicating the voltage and charge capacity of the battery during the charging control; Equipped with.

[0039] According to this aspect, by sending a charging instruction to a charging device, operating data indicating the battery voltage and charging capacity when a charging control set of charging for a first period and stopping charging for a second period is repeated can be obtained from the charging device.

[0040] Therefore, in this embodiment, even if an unevenness occurs in the chemical reaction inside the battery during charging of the battery in the first period, the unevenness of the chemical reaction can be suppressed by stopping charging for the second period, and accurate operation data can be obtained. Therefore, in this embodiment, the battery is charged at a higher rate than before during the first period, and a predetermined amount of charge can be applied to the battery in a shorter period than before. This shortens the time required to estimate the deterioration state of the battery using a non-destructive analysis method. As a result, for example, this embodiment can appropriately estimate the deterioration state of the battery using accurate operation data without stopping the daily operation of the battery.

[0041] (Embodiment) Hereinafter, a deterioration analysis system according to an embodiment of the present disclosure will be described with reference to the drawings. Fig. 1 is a diagram showing the overall configuration of a deterioration analysis system 1. The deterioration analysis system 1 is a system that analyzes the deterioration state of a battery 45 mounted on a vehicle 4 that is used daily for delivering packages, for business purposes, commuting, etc.

[0042] Specifically, as shown in FIG. 1, the degradation analysis system 1 includes a vehicle 4, an adapter 3, a charging device 5, and a server 2 (charging control device).

[0043] The vehicle 4 is equipped with a battery 45. The battery 45 is a rechargeable secondary battery, and is mainly composed of a positive electrode, a negative electrode, an electrolyte, and a separator. The vehicle 4 operates with power stored in the battery 45. The battery 45 is connected to the charging device 5 via the adapter 3. The battery 45 supplies the stored power to each part of the vehicle 4.

[0044] The adapter 3 is provided between the battery 45 and the charging device 5. The adapter 3 communicates with the server 2 and the charging device 5, and causes the charging device 5 to operate in accordance with control information received from the server 2. Specifically, the adapter 3 includes a communication unit 32, a power supply adapter 33, a sensor 31, and a control unit 30.

[0045] The communication unit 32 is configured with 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 the external devices to the control unit 30, and transmits information input from the control unit 30 to the external devices.

[0046] The power supply adapter 33 is connected to the power supply unit 51 of the charging device 5 and the battery 45 of the vehicle 4, and includes an internal power line (not shown) that connects the power supply unit 51 and the battery 45. The power supply adapter 33 is also connected to the control unit 30 and the sensor 31, and includes an internal communication line (not shown) that connects the control unit 30 and the sensor 31.

[0047] The sensor 31 includes, for example, a current sensor and a voltage sensor, etc. The sensor 31 is connected to the power line provided inside the power supply adapter 33, and detects the charging current supplied from the charging device 5 to the battery 45 and the open circuit voltage between the positive and negative electrodes of the battery 45 (battery voltage).

[0048] The control unit 30 is configured by a microcomputer including a CPU (Central Processing Unit), a memory, etc. The control unit 30 controls each part of the adapter 3 by executing a control program stored in the memory.

[0049] For example, when control information for controlling the charging device 5 transmitted from the server 2 is received by the communication unit 32, the control unit 30 transmits the received control information to the charging device 5 via the communication unit 32. As a result, 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 result of the sensor 31. The charging capacity of the battery 45 is the amount of power charged in the battery 45.

[0050] The charging device 5 controls charging of the battery 45 in accordance with control information received from the server 2 via the adapter 3. Specifically, the charging device 5 includes a communication unit 52 (a transmitter and a receiver), a power supply unit 51, and a control unit 50 (a charging control unit).

[0051] The communication unit 52 is configured with 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 the external devices to the control unit 50, and transmits information input from the control unit 50 to the external devices.

[0052] 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 power supplied from a commercial power source into predetermined AC power or DC power, and supplies the converted power to the battery 45 of the vehicle 4 to charge the battery 45.

[0053] The control unit 50 is configured by a microcomputer including a CPU (Central Processing Unit), a memory, etc. The control unit 50 controls each part of the charging device 5 by executing a control program stored in the memory.

[0054] For example, when control information indicating a charging instruction for battery 45 is received by communication unit 52, control unit 50 controls power supply unit 51 in accordance with the charging instruction indicated by the control information, starts, stops, and ends the supply of power to battery 45, and adjusts the amount of power supplied to battery 45. As a result, control unit 50 starts, stops, and ends the charging of battery 45, and adjusts the amount of charging, in accordance with the charging instruction indicated by the control information.

[0055] The server 2 communicates with the adapter 3 to control charging of the battery 45 of the vehicle 4 by the charging device 5. Specifically, the server 2 includes a storage unit 24, a communication unit 22, and a control unit 20.

[0056] The storage unit 24 is configured with a storage device such as an SSD (Solid State Drive) and / or an HDD (Hard Disk Drive) in which a predetermined control program is stored, 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 of the positive electrode, negative electrode, and electrolyte that constitute the battery 45.

[0057] The communication unit 22 is configured with 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 devices to the control unit 20, and transmits information input from the control unit 20 to the external devices.

[0058] The control unit 20 is configured with a microcomputer (computer) equipped with a CPU etc. The control unit 20 controls each part of the server 2 by executing a control program stored in the storage unit 24.

[0059] For example, the control unit 20 functions as an instruction unit 200 and an acquisition unit 201 by executing a control program stored in the storage unit 24 .

[0060] The instruction unit 200 instructs the charging device 5 to repeat a set of charging in a first period and stopping charging in a second period, and to end the charging control when the charged amount reaches a predetermined amount. The acquisition unit 201 acquires operation data indicating the voltage and charging capacity of the battery 45 at each end point of the second period during the charging control.

[0061] In the above description, an example has been described in which 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 communicate with each other via the network 7. However, this is not limiting, and 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 may communicate with each other directly, without the network 7, in accordance with a communication standard such as Bluetooth (registered trademark).

[0062] Next, an operation of estimating the degradation state of the battery 45 in the degradation analysis system 1 will be described. Fig. 2 is a flowchart showing an example of a process of the server 2 in the operation of estimating the degradation state of the battery 45. Fig. 3 is a flowchart showing an example of a process of the charging device 5 or the adapter 3 in the operation of estimating the degradation state of the battery 45.

[0063] Assume that a user connects the battery 45 of the vehicle 4 to the charging device 5 via the power supply adapter 33 (FIG. 1) of the adapter 3 using a charging cable (not shown), and then performs a predetermined operation to start charging the battery 45. The predetermined operation may be performed in any of the charging device 5, the vehicle 4, the adapter 3, and the server 2. The predetermined operation may also be performed on a mobile terminal such as a smartphone owned by the user. When the predetermined operation is performed, information indicating an instruction to start charging the battery 45 may be transmitted to the server 2. Note that, instead of the predetermined operation, information indicating an instruction to start charging may be transmitted to the server 2 based on a charging plan. In addition, when the charging plan is managed in the server 2, the server 2 may determine the start of charging.

[0064] When the communication unit 22 of the server 2 receives information indicating an instruction to start charging the battery 45, the instruction unit 200 determines whether it is time to perform maintenance charging (step S1), as shown in Fig. 2. Maintenance charging is a charging operation of the battery 45 that is performed to estimate the deterioration state of the battery 45.

[0065] For example, in step S1, if a predetermined period (e.g., three months) has passed since the date and time when the previous maintenance charging was performed, instructing unit 200 determines that it is time to perform maintenance charging (YES in step S1). On the other hand, if a predetermined period has not passed since the date and time when the previous maintenance charging was performed, instructing unit 200 determines that it is not time to perform maintenance charging (NO in step S1).

[0066] Furthermore, if the vehicle 4 is a company vehicle or a delivery vehicle for delivering luggage, the date and time when the vehicle 4 is next scheduled to be used may be determined in advance. In such a case, information indicating the date and time when the vehicle 4 is next scheduled to be used may be stored in advance in the storage unit 24 of the server 2. Then, in step S1, the instruction unit 200 may determine whether it is the timing to perform maintenance charging depending on whether a predetermined amount of time or more can be secured until the date and time when the vehicle 4 is next scheduled to be used. The predetermined amount of time may be set to a time longer than the time required for maintenance charging (for example, 10 hours), for example.

[0067] In step S1, if the instruction unit 200 determines that it is not the time to perform maintenance charging (NO in step S1), it transmits control information indicating a charging instruction for normal charging to the adapter 3 via the communication unit 22 (step S6).

[0068] 3, in the adapter 3, when the communication unit 32 receives the control information indicating the charging instruction for normal charging transmitted in step S6 (NO in step S11), the control unit 30 controls the communication unit 32 to transmit the control information to the charging device 5. In the charging device 5, when the communication unit 52 receives the control information, the control unit 50 performs normal charging according to the charging instruction indicated by the control information (step S19). That is, the control unit 50 causes the power supply unit 51 to convert the power supplied from the commercial power source into a predetermined AC power or DC power, and supplies the converted power to the battery 45 of the vehicle 4.

[0069] 2, when instructing unit 200 determines in step S1 that it is time to perform maintenance charging (YES in step S1), it transmits control information indicating a charging instruction for maintenance charging to adapter 3 via communication unit 22 (step S2). The charging instruction for maintenance charging is an instruction to repeat charging control in which battery 45 is charged with a charging current of a predetermined current value for a first period, and then charging is stopped for a second period, and to end the charging control when the charged amount reaches a predetermined amount.

[0070] 3, in the adapter 3, when the communication unit 32 receives the control information indicating a charging instruction for maintenance charging transmitted in step S2 (YES in step S11), the control unit 30 controls the communication unit 32 to transmit the control information to the charging device 5. The control unit 30 also controls the sensor 31 to periodically detect the charging current supplied to the battery 45 and the open circuit voltage of the battery 45. The control unit 30 also periodically calculates the charging capacity of the battery 45 based on the detection result of the sensor 31.

[0071] Meanwhile, in the charging device 5, when the communication unit 52 receives the control information indicating a charging instruction for maintenance charging, the control unit 50 starts the charging operation of the battery 45 in accordance with the charging instruction for maintenance charging indicated by 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.

[0072] After starting the charging operation of the battery 45 in step S12, the control unit 50 continues the charging operation until the first period T1 has elapsed (NO in step S13). Then, when the first period T1 has elapsed after the start of the charging operation (YES in step S13), the control unit 50 pauses the charging operation (step S14). Specifically, in step S14, the control unit 50 controls the power supply unit 51 to stop the supply of charging current to the battery 45.

[0073] After the charging operation is paused in step S14, the control unit 50 is in a standby state until the second period T2 has elapsed (NO in step S15). After the charging operation is paused in step S14, when the second period T2 has elapsed (YES in step S15), the control unit 50 transmits information indicating the end of the second period T2 to the adapter 3. In the adapter 3, when the communication unit 32 receives the information indicating the end of the second period T2, the control unit 30 records in memory the operation data indicating the open circuit voltage of the battery 45 detected by the sensor 31 at the time of the reception and the charge capacity of the battery 45 calculated at the time of the reception in association with the date and time of the reception (step S16). Meanwhile, the control unit 50 determines whether the charge amount has reached a predetermined amount (step S17). Here, the charge amount indicates the amount of power supplied to the battery 45.

[0074] Specifically, in step S17, the control unit 50 calculates the integrated value of the charging current supplied to the battery 45 as the charge amount, and determines whether the calculated charge amount is equal to or greater than a predetermined amount. In step S17, if the control unit 50 determines that the charge amount has reached the predetermined amount (YES in step S17), it transmits information indicating the end of maintenance charging to the adapter 3.

[0075] In the adapter 3, when the communication unit 32 receives information indicating the end of maintenance charging, the control unit 30 controls the communication unit 32 to transmit the operating data stored in memory, together with information indicating the date and time associated with the operating data, to the server 2 (step S18).

[0076] On the other hand, in step S17, when the control unit 50 determines that the charge amount has not reached the predetermined amount (NO in step S17), the control unit 50 repeats the processes in steps S12 and after. As a result, the control unit 50 repeats the charging control of the set of the charging operation in the first period T1 and the charging pause in the second period T2.

[0077] As shown in FIG. 2, in the server 2, after step S2, when the communication unit 22 receives the operational data and the information indicating the date and time, the acquisition unit 201 acquires the operational data received by the communication unit 22 in order starting from the data corresponding to the information indicating the oldest date and time (step S3).

[0078] Next, the control unit 20 calculates differential data of the open circuit voltage with respect to the charge capacity using the operation data acquired in step S3 (step S4). Specifically, the control unit 20 calculates the differential data using the following formula (1).

[0079] dV / dQ(n) = (V n -V n-1 ) / (Q n -Q n-1 ) · · · (1) In formula (1), dV / dQ(n) represents the differential data at date and time n. n indicates the open circuit voltage included in the operation data corresponding to date and time n, and Q n indicates the charging capacity included in the operation data corresponding to date and time n. V n-1 Q indicates the open circuit voltage included in the operation data corresponding to date and time n-1 acquired before the operation data corresponding to date and time n. n-1 indicates the charge capacity included in the operation data corresponding to date and time n-1 acquired before the operation data corresponding to date and time n. In order to suppress noise components included in the above-mentioned differential data dV / dQ(n), for example, a process such as averaging the values ​​of the differential data dV / dQ(n) at adjacent dates and times may be performed.

[0080] Next, the control unit 20 estimates the deterioration state of the battery 45 by analyzing the peak in the differential data calculated in step S4 (step S5), and ends the process. Step S5 will be described in detail later.

[0081] In step S2, the control unit 20 transmits control information indicating a charging instruction for maintenance charging to the adapter 3, and then waits for processing until the operation data is received. However, instead of this, the control unit 20 may transmit control information indicating an instruction to execute steps S12 and S14 to the charging device 5 via the adapter 3, and perform the determination processes of steps S13, S15, and S17.

[0082] In this case, in order to enable the control unit 20 to perform the judgment process of step S17, after the control unit 30 of the adapter 3 receives control information indicating an instruction to execute step S12 via the communication unit 32, it is sufficient to cause the communication unit 32 to transmit information indicating the charging current detected by the sensor 31 to the server 2.

[0083] (Examples of charging current and open circuit voltage) Next, a specific example of the charging current supplied to the battery 45 and the open circuit voltage of the battery detected during maintenance charging will be described. In this specific example, it is assumed that maintenance charging is started when the battery 45 is in an empty state. Fig. 4 is a graph showing an example of the charging current I supplied to the battery 45 and the open circuit voltage V of the battery 45 detected during maintenance charging.

[0084] Graph G1 shown in the upper part of Fig. 4 is a graph showing time series changes in charging current I during maintenance charging, with the horizontal axis showing time and the vertical axis showing charging current I. Graph G2 shown in the lower part of Fig. 4 is a graph showing time series changes in open-circuit voltage V of battery 45 detected by sensor 31 during maintenance charging, with the horizontal axis showing time and the vertical axis showing open-circuit voltage V.

[0085] When maintenance charging is started, as shown in graph G1, a charging current I of current value Ic is supplied to the battery 45 for a first period T1. This causes the open circuit voltage V of the battery 45 detected by the sensor 31 to gradually increase as shown in graph G2.

[0086] After the first period T1 has elapsed, the charging operation is stopped during the second period T2, and as shown in graph G1, the charging current I is no longer supplied to the battery 45. This gradually suppresses the unevenness of the chemical reaction that occurred inside the battery 45 during the first period, and as shown in graph G2, the open-circuit voltage V of the battery 45 detected by the sensor 31 gradually decreases. Then, at the end Ts of the second period T2, operation data indicating the open-circuit voltage V detected by the sensor 31 and the charge capacity of the battery 45 calculated by the control unit 30 are transmitted to the server 2.

[0087] In this way, in maintenance charging, charging control of a set of charging in the first period T1 and charging stop in the second period T2 is repeated. Then, maintenance charging ends at the time Tm when the amount of charge supplied from the charging device 5 to the battery 45 reaches a predetermined amount. The amount of charge supplied from the charging device 5 to the battery 45 is calculated by the following formula (2).

[0088] Pc = Ic × T1 × m (2) In formula (2), Pc indicates the charge amount supplied from the charging device 5 to the battery 45, and m indicates the number of times charging has been performed in the first period T1 up until the time the charge amount was calculated.

[0089] 4, the second period T2 is set to be shorter than the first period T1. That is, in this specific example, the period during which the battery 45 is charged is set to be longer than the period during which the charging of the battery 45 is stopped, so that maintenance charging for estimating the degradation state of the battery 45 can be efficiently performed. However, this is not limited to the above, and if a long charging time can be ensured, the second period T2 may be set to be longer than the first period T1.

[0090] 3, the current value Ic of the charging current I, the first period T1, and the second period T2 are set so that the battery 45 can be charged to a predetermined amount (fully charged) by maintenance charging in a predetermined time (for example, about 7 hours). Specifically, the current value Ic of the charging current I is set to 0.2 C which completes charging of the battery 45 in 5 hours. The first period T1 is set to 3 minutes, and the second period T2 is set to 1 minute. However, the current value Ic of the charging current I and the first period T1 are not limited to this, and may be set so that the amount of charge in the first period T1 is about 1% of the SOC of the battery 45. In other words, when maintenance charging is performed until the state of charge of the battery 45 changes from an empty state to a fully charged state, charging control may be repeated about 100 times.

[0091] The number of times that charging control is repeated may be set appropriately so that the amount of charge reaches a predetermined amount within a predetermined time (e.g., 8 hours) from the start of maintenance charging. The number of times that charging control is repeated (e.g., 100 times) may be set so that the amount of charge reaches a predetermined amount within a predetermined time (e.g., 8 hours) from the start of maintenance charging, and the first period T1 and the second period T2 may be set appropriately accordingly.

[0092] Furthermore, if it is difficult to adjust the number of times charging control is repeated, the first period T1, and the second period T2 so that the charge amount reaches a predetermined amount within a predetermined time from the start of maintenance charging, the current value Ic of the charging current I in the first period T1 may be adjusted. However, the higher the current value Ic, the greater the unevenness of the chemical reaction occurring inside the battery in the first period T1. For this reason, the higher the current value Ic, the longer the second period T2 may be adjusted.

[0093] (Example of Estimation of Deterioration State of Battery 45) Next, a specific example of the estimation of the deterioration state of the battery 45 performed in step S5 (FIG. 2) will be described. n5 is a graph G3 showing an example of the relationship between the differential data dV / dQ(n) and the charge capacity Q of the battery 45 at the date and time n, which is calculated in step S4 (FIG. 2). n In step S5 (FIG. 2), the control unit 20 calculates the charge capacity Q n and the differential data dV / dQ(n), a graph G3 is generated.

[0094] The control unit 20 determines inflection points N1, P1, N2, and P2 in the generated graph G3 where the differential data dV / dQ(n) changes from an increasing trend to a decreasing trend as peaks in the differential data dV / dQ(n).

[0095] It is possible to determine which open-circuit voltage of the positive electrode or the negative electrode each peak corresponds to based on experimental values ​​or the like and in accordance with the materials of the components of the positive electrode and the negative electrode of the battery 45. In the example of Fig. 5, inflection points N1, P1, N2, and P2, which are peaks appearing in the differential data dV / dQ(n), correspond to the open-circuit voltages of the negative electrode, positive electrode, negative electrode, and positive electrode, respectively.

[0096] Therefore, the control unit 20 calculates the charge capacity Q corresponding to the inflection points P1 and P2, which are peaks corresponding to the open circuit voltage of the positive electrode. n The controller 20 estimates the deterioration state of the capacity of the positive electrode by performing an analysis process on the differential data dV / dQ(n) and the charge capacity Q corresponding to the inflection points N1 and N2, which are peaks corresponding to the open circuit voltage of the negative electrode. n The deterioration state of the capacity of the negative electrode is estimated by performing an analysis process on the differential data dV / dQ(n).

[0097] In addition, the control unit 20 calculates the charge capacity Q corresponding to the inflection points N1, P1, N2, and P2. n By performing an analysis of the differential data dV / dQ(n), the reaction balance between the positive and negative electrodes is estimated.

[0098] Depending on the materials of the components of the positive and negative electrodes of the battery 45, only a peak corresponding to the open-circuit voltage of either the positive or negative electrode may appear in the differential data dV / dQ(n). In this case, the control unit 20 performs an analysis process on the peak corresponding to the open-circuit voltage of the one electrode, thereby estimating the deterioration state of the capacity of the one electrode.

[0099] (Variation 1) In the above embodiment, an example has been described in which the open circuit voltage between the positive and negative electrodes of the battery 45 is detected during maintenance charging. However, when the battery 45 can be disassembled in a laboratory or the like, the open circuit voltage of the positive electrode and the open circuit voltage of the negative electrode may be detected separately by the sensor 31 (FIG. 1). In addition, the adapter 3 may transmit to the server 2 operation data indicating the detected open circuit voltages of the positive and negative electrodes and the charge capacity of the battery 45.

[0100] In this case, in step S4 (FIG. 2), the control unit 20 may use the operational data acquired in step S3 (FIG. 2) to separately calculate differential data of the open circuit voltage of the positive electrode with respect to the charge capacity (hereinafter, positive electrode differential data) and differential data of the open circuit voltage of the negative electrode with respect to the charge capacity (hereinafter, negative electrode differential data).

[0101] Then, the control unit 20 calculates the charge capacity Q n A graph showing the relationship between the capacitance and the differential data of the positive electrode may be generated, and the capacity deterioration of the positive electrode may be estimated by analyzing peaks that appear in the differential data of the positive electrode in the graph.

[0102] Similarly, the control unit 20 detects the charge capacity Q n A graph showing the relationship between the capacitance and the differential data of the negative electrode may be generated, and the capacity deterioration of the negative electrode may be estimated by analyzing peaks that appear in the differential data of the negative electrode in the graph.

[0103] Alternatively, similarly, the sensor 31 may detect only one of the open circuit voltage of the positive electrode and the open circuit voltage of the negative electrode, and the capacity deterioration of only that one electrode may be estimated.

[0104] (Variation 2) In the above embodiment, an example has been described in which, in the maintenance charging, charging control of a set of charging in the first period T1 and stopping charging in the second period is repeated without changing the current value Ic of the charging current I, the first period T1, and the second period T2. However, instead of this, the charging capacity Q n In accordance with the range of the charging current I, the charging control may be repeated by changing one or more of the current value Ic of the charging current I, the first period T1, and the second period T2.

[0105] For example, by estimating the deterioration state of the battery 45 in the past, the charge capacity Q n It is assumed that it is possible to grasp in advance the relationship between the differential data dV / dQ(n) of the battery 45 and the charge capacity range (e.g., 0.5 Ah-0.8 Ah) where a peak (e.g., N1) appears in the differential data dV / dQ(n) of the battery 45 may be determined as the first range.

[0106] First, while the charge capacity of battery 45 calculated by control unit 30 is within the first range, one of the current value Ic of charging current I and the first period T1 may be changed when the charge capacity is within the first range and when the charge capacity is outside the first range. This allows charging control to be repeated more times than while the charge capacity is outside the first range, increasing the amount of acquired operation data, and improving the accuracy of peaks appearing in differential data dV / dQ of battery 45.

[0107] Specifically, while the charge capacity is within the first range, the current value Ic of the charge current I may be set smaller than while the charge capacity is outside the first range. Alternatively, while the charge capacity is within the first range, the first period T1 may be set shorter than while the charge capacity is outside the first range. In this way, while the charge capacity is within the first range, the amount of charge charged during the first period T1 may be reduced, and the number of repetitions of the charge control when the charge capacity is within the first range may be increased.

[0108] Secondly, the second period T2 may be set longer while the charge capacity is within the first range than while the charge capacity is outside the first range. This may improve the accuracy of the peak appearing in the differential data dV / dQ(n) of the battery 45. It is possible to suppress unevenness in the chemical reaction occurring inside the battery 45 during charging in the first period T1.

[0109] In the first or second case, the second period T2 may be shortened (may be set to 0) while the charge capacity is outside the first range. Also, while the charge capacity is outside the first range, the current value Ic of the charging current I may be set to be larger than while the charge capacity is within the first range. This makes it possible to shorten the time required for maintenance charging.

[0110] It should be noted that one or more of the above-mentioned methods of changing the current value Ic of the charging current I, the first period T1, and the second period T2 may be combined.

[0111] (Variation 3) In the above embodiment, an example in which maintenance charging is started when the battery 45 is in an empty state has been described with reference to Fig. 4. However, maintenance charging may be started when the battery 45 is not in an empty state, and maintenance charging may be terminated when the charge amount reaches a predetermined amount. Then, on another occasion, maintenance charging may be started when the battery 45 is in an empty state, and maintenance charging may be terminated when the charge amount reaches a predetermined amount.

[0112] In this manner, maintenance charging may be performed on multiple occasions, and in step S5 (FIG. 2), a suitable peak may be selected from overlapping peaks appearing in the differential data dV / dQ(n) calculated from the operational data acquired on the multiple occasions, or the analysis results of the overlapping peaks may be averaged to estimate the degradation state of battery 45.

[0113] (Variation 4) In the above embodiment and modified examples, an example has been described in which the degradation state of the battery 45 is estimated in the server 2. Alternatively, the degradation analysis system may be configured to not include a server 2 and to estimate the degradation state of the battery 45 in the adapter.

[0114] Fig. 6 is a diagram showing the overall configuration of a deterioration analysis system 1a of the fourth modified example. Specifically, as shown in Fig. 6, in the deterioration analysis system 1a of this modified example, an adapter 3a (charging control device) includes a storage unit 34 similar to the storage unit 24 (Fig. 1). A control unit 30a of the adapter 3a functions similarly to the control unit 20 (Fig. 1) of the server 2, and functions as an instruction unit 300 and an acquisition unit 301 similar to the instruction unit 200 and the acquisition unit 201 (Fig. 1). Note that, in this modified example as well, the communication unit 32 of the adapter 3a and the communication unit 52 of the charging device 5 may directly communicate with each other without going through the network 7.

[0115] (Variation 5) Unlike the above-described embodiment and modified examples, the degradation analysis system may be configured to estimate the degradation state of the battery 45 in the vehicle without including the server 2 and the adapters 3, 3a.

[0116] FIG. 7 is a diagram showing the overall configuration of the deterioration analysis system 1b of the modified example 5. Specifically, as shown in FIG. 7, in the deterioration analysis system 1b of the modified example, a vehicle 4b (charging control device) includes a storage unit 44 similar to the storage unit 24 (FIG. 1), a power supply adapter 43 similar to the power supply adapter 33, the sensor 31, and the communication unit 32 (FIG. 1) of the adapter 3. The vehicle 4b also includes a control unit 40b similar to the control unit 30a of the adapter 3a (FIG. 6), and the control unit 40b functions as an instruction unit 400 and an acquisition unit 401 similar to the instruction unit 300 and the acquisition unit 301. Note that, in the modified example, the communication unit 42 of the vehicle 4b and the communication unit 52 of the charging device 5 may directly communicate with each other without going through the network 7.

[0117] (Variation 6) In the above embodiment and modified examples, the charging device 5 may be provided with a power supply adapter similar to the power supply adapter 33 (FIG. 1) and a sensor similar to the sensor 31 (FIG. 1), and the control unit 50 (FIGS. 1, 6, 7) of the charging device 5 may calculate the charge capacity of the battery 45 based on the detection results of the sensors. The control unit 50 (FIGS. 1, 6, 7) of the charging device 5 may then transmit operation data indicating the detected and calculated open circuit voltage and charge capacity of the battery 45 to the acquisition unit 201 (FIG. 1) of the server 2, the acquisition unit 301 (FIG. 6) of the adapter 3a, and the acquisition unit 401 (FIG. 7) of the vehicle 4b via the communication unit 52 (FIGS. 1, 6, 7).

[0118] A power supply adapter similar to the power supply adapter 33 (FIG. 1) and a sensor similar to the sensor 31 (FIG. 1) may be provided in any of the vehicle 4 (FIG. 1), 4b (FIG. 7), the adapter 3 (FIG. 1), 3a (FIG. 6), the server 2 (FIG. 1), and the charging device 5 (FIGS. 1, 6, and 7), and the detection results of the sensors may be transmitted to the server 2 (FIG. 1), the adapter 3a (FIG. 6), and the vehicle 4b (FIG. 7) as needed. The charge capacity of the battery 45 may be calculated and operation data may be acquired in the acquisition unit 201 (FIG. 1) of the server 2, the acquisition unit 301 (FIG. 6) of the adapter 3a, and the acquisition unit 401 (FIG. 7) of the vehicle 4b. [Industrial Applicability]

[0119] INDUSTRIAL APPLICABILITY The present disclosure is useful for appropriately estimating the degradation state of a secondary battery using a non-destructive analysis method without stopping the daily operation of the secondary battery.

Claims

1. 1. A computer-implemented information processing method, comprising: A charging device that charges batteries. Repeating a set of charging control including a first period of charging and a second period of stopping charging; When the charge amount reaches a predetermined amount, the charging control is terminated. Instruct them to do so. acquiring operation data indicating a voltage and a charge capacity of the battery at each end point of the second period during the charging control; The second period is set to be longer while the charge capacity is within the first range than while the charge capacity is outside the first range. Information processing methods.

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

3. The number of times the charging control is repeated is set so that the amount of charge reaches the predetermined amount within a predetermined time.

3. The information processing method according to claim 1 or 2.

4. The first period and the second period are set so that the charge amount reaches the predetermined amount within a predetermined time. The information processing method according to claim 1 .

5. When a predetermined time or more can be secured for charging the battery, the instruction is issued. The information processing method according to any one of claims 1 to 4.

6. Calculating differential data of the voltage with respect to the charge capacity using the operational data; A deterioration state of the battery is estimated by analyzing peaks in the differential data. The information processing method according to any one of claims 1 to 5.

7. the peaks in the differential data include at least one of a first peak corresponding to a positive electrode of the battery and a second peak corresponding to a negative electrode of the battery; In estimating the deterioration state of the battery, a deterioration state of at least one of a positive electrode and a negative electrode of the battery is estimated by analyzing at least one of the first peak and the second peak. The information processing method according to claim 6.

8. The number of times the charging control is repeated is set to be greater while the charging capacity is within a first range than while the charging capacity is outside the first range. The information processing method according to any one of claims 1 to 7.

9. The charging current in the charging control is set smaller while the charging capacity is within a first range than while the charging capacity is outside the first range. The information processing method according to any one of claims 1 to 8.

10. The first range is a range of the charge capacity in which a peak appears in differential data of the voltage with respect to the charge capacity, the differential data being calculated using the operation data.

10. The information processing method according to claim 8 or 9.

11. A charge control device that controls a charging device that charges a battery, an instruction unit that instructs the charging device to repeat a set of charging control including charging in a first period and stopping charging in a second period, and to end the charging control when a charged amount reaches a predetermined amount; an acquisition unit that acquires operation data indicating a voltage and a charge capacity of the battery at each end point of the second period during the charging control; Equipped with The second period is set to be longer while the charge capacity is within the first range than while the charge capacity is outside the first range. Charging control device.

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