Controller, control method, and program

Abstract

To prevent deterioration of a lithium metal battery.SOLUTION: A determination device comprises: an acquisition unit that acquires the transition curve of the voltage of a lithium metal battery comprising a negative electrode including lithium; and a determination unit that determines recommendation suppression time for recommending suppression of charge and discharge of the lithium metal battery, on the basis of the rate of change in the voltage within a short time constant range corresponding to a range of a short time constant in the transition curve.SELECTED DRAWING: Figure 2

Description

[Technical Field]

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

[0002] In recent years, research and development has been conducted to contribute to energy efficiency so that more people can have access to affordable, reliable, sustainable, and advanced energy. Regarding this technology, lithium metal batteries, which use lithium metal as a negative electrode, have attracted attention as a secondary battery. A lithium metal battery includes a positive electrode, a negative electrode having a metallic lithium layer, and an electrolyte disposed between the positive electrode and the negative electrode. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2023 / 118960 [Patent Document 2] Japanese Patent Publication No. 2023-17581 [Patent Document 3] Japanese Patent Publication No. 2022-113377 Summary of the Invention [Problem to be solved by the invention]

[0004] Lithium metal batteries use lithium in the negative electrode and have a mechanism for charging and discharging by precipitation and dissolution of lithium. Secondary batteries often cannot fully demonstrate their durability unless the charge and discharge rate is properly controlled, and this is also true for lithium metal batteries.

[0005] The present invention has been made in consideration of the above circumstances, and one of its objects is to suppress the deterioration of the durability of lithium metal batteries, thereby contributing to energy efficiency. [Means for solving the problem]

[0006] The control device, control method, and program according to the present invention employ the following configuration. (1): A control device according to one embodiment of the present invention is a control device comprising: an acquisition unit that acquires charge / discharge rate information regarding the charge / discharge rate during charging / discharging of a lithium metal battery having a negative electrode containing lithium; and a determination unit that determines the charge / discharge content of the lithium metal battery based on the charge / discharge rate information.

[0007] (2): In the above aspect (1), the charge / discharge rate information is discharge rate information regarding the discharge rate for the lithium metal battery, and when the charge rate included in the charge / discharge rate information is equal to or less than a first specified value, the determination unit determines the charge / discharge content to be a small charge current.

[0008] (3): In the above aspect (1), the charge / discharge rate information is discharge rate information regarding the current discharged from the lithium metal battery, and when the discharge rate included in the charge / discharge rate information is equal to or less than a second specified value, the determination unit determines the discharge current to be large as the charge / discharge content.

[0009] (4) In the above aspect (1), the charge / discharge rate information is information relating to an average discharge rate or an average charge / discharge rate difference within a specified time period.

[0010] (5): In the above aspect (1), the acquisition unit acquires the charge / discharge rate based on information relating to the charge / discharge history of the lithium metal battery.

[0011] (6): In the aspect (5) above, the lithium metal battery is mounted on a vehicle, and the determination unit determines the charging and discharging details when the vehicle is performing charging and discharging between the vehicle and an external device.

[0012] (7): A control method according to one embodiment of the present invention is a control method in which a computer acquires charge / discharge rate information regarding a charge / discharge rate during charging / discharging of a lithium metal battery having a negative electrode containing lithium, and determines the charge / discharge content of the lithium metal battery based on the charge / discharge rate information.

[0013] (8): A program according to one embodiment of the present invention is a program that causes a computer to acquire charge / discharge rate information regarding the charge / discharge rate during charging / discharging of a lithium metal battery having a negative electrode containing lithium, and determine the charge / discharge details for the lithium metal battery based on the charge / discharge rate information. [Effects of the Invention]

[0014] According to the aspects (1) to (8), it is possible to suppress a decrease in the durability of the lithium metal battery. [Brief explanation of the drawings]

[0015] [Figure 1] 1 is a diagram showing an example of the configuration of a vehicle M equipped with a control device 100 according to an embodiment. [Figure 2] 1 is a diagram illustrating an example of the configuration of a control device 100. FIG. [Figure 3] 10 is a diagram showing an example of a visualized first reference control map 121 and a visualized first control map 122. FIG. [Figure 4] 10 is a diagram showing an example of a visualized second reference control map 123 and a visualized second control map 124. FIG. [Figure 5] 4 is a flowchart showing an example of processing by the control device 100. DETAILED DESCRIPTION OF THE INVENTION

[0016] Hereinafter, embodiments of a control device, a control method, and a program according to the present invention will be described with reference to the drawings.

[0017] FIG. 1 is a diagram showing an example of the configuration of a vehicle M equipped with a control device 100 according to an embodiment. The control device 100 according to the embodiment controls the amount of current charged and discharged to a lithium metal battery 10 equipped in the vehicle M. The lithium metal battery 10 has a negative electrode containing lithium. The lithium metal battery 10 is a secondary battery that can be charged and discharged.

[0018] Vehicle M is included in so-called V2H (Vehicle to Home) and V2X (Vehicle to X). Vehicle M can be charged or discharged between itself and an external device such as charging / discharging equipment 80. When starting charging or discharging between vehicle M and charging / discharging equipment 80, charging / discharging equipment 80 transmits a V2H request to vehicle M. Upon receiving the V2H request, vehicle M starts charging or discharging between itself and charging / discharging equipment 80.

[0019] The charging / discharging equipment 80 discharges current to the lithium metal battery 10 mounted on the vehicle M to charge the lithium metal battery 10. The current regulating device 70 mounted on the vehicle M converts AC current to DC current using the charging / discharging equipment 80, steps down the current, and charges the lithium metal battery 10. The lithium metal battery 10 mounted on the vehicle M discharges current to charge the charging / discharging equipment 80. The current regulating device 70 mounted on the vehicle M converts the DC current discharged by the lithium metal battery 10 to AC current, steps up the current, and charges the charging / discharging equipment 80.

[0020] In addition to the lithium metal battery 10, the vehicle M is equipped with an electric device 40, a measuring device 50, a control unit 60, and a current adjusting device 70. The measuring device 50 includes, for example, a voltage detector 51 and a current detector 52. The control unit 60 includes, for example, a control device 100 and an ECU (Electronic Control Unit) 200.

[0021] The lithium metal battery 10 is, for example, a semi-solid battery. The lithium metal battery 10 includes, for example, a positive electrode 11, a negative electrode 12, and an electrolyte 13. The positive electrode 11 includes, for example, a positive electrode current collector 11A and a positive electrode active material layer 11B. The positive electrode current collector 11A is made of, for example, a current collecting foil such as aluminum. The positive electrode active material layer 11B is made of, for example, a layer of lithium cobalt oxide.

[0022] The negative electrode 12 includes, for example, a negative electrode current collector 12A and a negative electrode active material layer 12B. The negative electrode current collector 12A is made of, for example, a current collecting foil such as copper. The negative electrode active material layer 12B is made of, for example, a metallic lithium layer. The electrolyte 13 is a semi-solid electrolyte containing lithium ions (Li+). The electrolyte 13 is partitioned into a positive electrode 11 side and a negative electrode 12 side by a separator 13S.

[0023] During discharge, when the lithium metal battery 10 supplies power to an electrical device 40 mounted on the vehicle M, lithium ions Li+ flow from the negative electrode active material layer 12B through the separator 13S to the positive electrode 11. Along with the flow of lithium ions Li+, electrons e flow from the negative electrode 12 through the circuit of the electrical device 40 to the positive electrode 11. Due to the flow of lithium ions Li+ and electrons e, a current flows from the positive electrode 11 to the negative electrode 12, discharging the lithium metal battery 10. In the negative electrode active material layer 12B, metallic lithium dissolves as the lithium metal battery 10 discharges.

[0024] The lithium metal battery 10 is charged by a charging / discharging device 70 located outside the vehicle M. The charging / discharging device 70 is installed, for example, at the home of the owner of the vehicle M or at a charging station. During charging, lithium ions Li+ flow from the positive electrode active material layer 11B through the separator 13S to the negative electrode 12 side.

[0025] Along with the flow of lithium ions Li+, electrons e flow from the positive electrode 11 to the 12 side through the charge / discharge equipment 80. The flow of lithium ions Li+ and electrons e causes a current to flow from the negative electrode 12 side to the positive electrode 11 side, charging the lithium metal battery 10. In the negative electrode active material layer 12B, metallic lithium is deposited as the lithium metal battery 10 is charged.

[0026] The electrical equipment 40 includes various devices that are mounted on the vehicle M and are supplied with power by the lithium metal battery 10. The electrical equipment 40 includes, for example, a traction motor for driving the vehicle M, an air conditioning control device for controlling the air conditioning in the passenger compartment of the vehicle M, and a monitor for displaying images to provide various information to the occupants.

[0027] The voltage detector 51 in the measuring device 50 detects the voltage value between the terminals of the lithium metal battery 10. The voltage detector 51 outputs the detected voltage value to the control device 100 of the control unit 60. The current detector 52 detects the current value of the current flowing from the positive electrode 11 side to the negative electrode 12 side of the lithium metal battery 10. The current detector 52 outputs the detected current value to the control device 100.

[0028] 2 is a diagram showing an example of the configuration of the control device 100. The control device 100 includes, for example, a communication unit 110, a storage unit 120, and a processing unit 130. The communication unit 110 transmits and receives signals between the control device 100 and an external device. For example, the communication unit 110 transmits a current supply signal generated by the processing unit 130 to the AC power supply 20. The communication unit 110 receives a current signal transmitted by the ammeter 30. The transmission and reception performed by the communication unit 110 may be wired communication via wiring or wireless communication via a network.

[0029] The storage unit 120 is formed of, for example, a hard disk drive (HDD) or a flash memory. The storage unit 120 may be a drive device external to the control device 100. The storage unit 120 includes, for example, a first reference control map 121, a first control map 122, a second reference control map 123, a fourth reference control map, and a V2H history 125.

[0030] 3 is a diagram showing an example of visualized first reference control map 121 and first control map 122. Both first reference control map 121 and first control map 122 are maps that show, for example, the magnitude of the charging current according to the difference between the charge and discharge rates when charging a lithium metal battery. First control map 122 is a map created so that the charging current is smaller than that of first reference control map 121.

[0031] The V2H history 125 includes information on the history of charging and discharging between the lithium metal battery 10 and an external device via V2H, which is formed by the vehicle M and an external device such as a charging and discharging facility 80. In the vehicle M, the V2H history 125 is updated every time charging and discharging is performed via V2H. The V2H history 125 is an example of a charging and discharging history.

[0032] 4 is a diagram showing an example of visualized second reference control map 123 and second control map 124. Both second reference control map 123 and second control map 124 are maps that show the magnitude of discharge current according to the discharge rate during discharge of a lithium metal battery. Second control map 124 is a map created so that the discharge current is larger than that of second reference control map 123.

[0033] The processing unit 130 includes, for example, an acquisition unit 131, a determination unit 132, and a notification unit 133. These components are realized by, for example, a hardware processor such as a CPU (Central Processing Unit) executing a program (software). Some or all of these components may be realized by hardware (including circuitry) such as an LSI (Large Scale Integration), an ASIC (Application Specific Integrated Circuit), an FPGA (Field-Programmable Gate Array), or a GPU (Graphics Processing Unit), or may be realized by a combination of software and hardware.

[0034] The program may be stored in advance in a storage unit 120 (a storage device with a non-transitory storage medium) such as an HDD or flash memory, or may be stored in a removable storage medium (a non-transitory storage medium) such as a DVD or CD-ROM, and installed by inserting the storage medium into a drive device.

[0035] The acquisition unit 131 acquires a V2H request transmitted by the charging / discharging equipment 80. The acquisition unit 131 acquires the voltage value output by the voltage detector 51 and the current value output by the current detector 52. The acquisition unit 131 adds the acquired voltage value and current value to the V2H history 125 stored in the storage unit 120. The acquisition unit 131 updates the V2H history 125 by adding the voltage value and current value.

[0036] The acquisition unit 131 calculates the magnitude (current value) of the charge / discharge current of the lithium metal battery 10 and the difference between the charge / discharge currents based on the detection results of the voltage detector 51 and the current detector 52, and acquires this as charge / discharge rate information relating to the charge / discharge rate during charging / discharging of the lithium metal battery 10. The charge / discharge rate includes a discharge rate and a charge / discharge rate difference, and the charge / discharge rate information includes discharge rate information and charge / discharge rate difference information. The charge / discharge rate difference may be replaced by a charge rate. The charge / discharge rate information is information relating to an average discharge rate or an average charge / discharge rate difference within a specified time period. The specified time period may be determined as appropriate.

[0037] The determination unit 132 determines the charge / discharge details for the lithium metal battery 10 based on the charge / discharge rate information acquired by the acquisition unit 131. For example, when the charge / discharge rate difference included in the charge / discharge rate difference information is equal to or smaller than a first specified value R1, the determination unit 132 determines the charge current to be small as the charge details. For example, when the discharge rate included in the discharge rate information is equal to or smaller than a second specified value R2, the determination unit 132 determines the discharge current to be large as the discharge details.

[0038] The determination unit 132 selects, as a recommended charge / discharge control map, a control map to be referenced when determining the charge current, based on, for example, the charge / discharge rate difference included in the charge / discharge rate difference information acquired by the acquisition unit 131. For example, when the charge / discharge rate difference is equal to or less than a first specified value R1, the determination unit 132 selects the first control map 122 and determines the charge current by referring to the first control map 122 for the charge / discharge rate difference. For example, when the charge / discharge rate difference exceeds the first specified value R1, the determination unit 132 selects the first reference control map 121 and determines the charge current by referring to the first reference control map 121 for the charge / discharge rate difference.

[0039] The determination unit 132 selects, as the recommended charge / discharge control map, a control map to be referenced when determining the discharge current, based on, for example, the discharge rate included in the discharge rate information acquired by the acquisition unit 131. For example, when the discharge rate exceeds a second specified value R2, the determination unit 132 selects the second control map 124 and determines the discharge current by referring to the second control map 124 for the discharge rate. For example, when the discharge rate is equal to or less than the second specified value R2, the determination unit 132 selects the second reference control map 123 and determines the charge current by referring to the second reference control map 123 for the discharge rate.

[0040] The determination unit 132 determines the details of charging and discharging when, for example, the vehicle M is charging and discharging between the vehicle M and an external device such as the charging and discharging facility 80. For example, the determination unit 132 determines the details of charging and discharging when, in V2H, charging and discharging are repeated with a current amount equal to or greater than a specified amount. The specified current amount and the frequency of repeated charging and discharging may be determined as appropriate.

[0041] The determination unit 132 determines, for example, a discharge current when the lithium metal battery 10 of the vehicle M is discharging current to the charging / discharging equipment 80. The determination unit 132 determines, for example, a charge current when the lithium metal battery 10 of the vehicle M is charging the current discharged by the charging / discharging equipment 80. The discharge current and the charge current are specified by a current value, but may also be specified by a current amount.

[0042] The notification unit 133 notifies the ECU 200 of the charge current or discharge current determined by the determination unit 132. The ECU 200 generates current value information relating to the current value of charging and discharging the lithium metal battery 10 based on the charge current and discharge current notified by the notification unit 133. The ECU 200 transmits the generated current value information to the current adjustment device 70.

[0043] Next, the processing in the control device 100 of the embodiment will be described. Fig. 5 is a flowchart showing an example of the processing in the control device 100. The processing shown in Fig. 5 is executed, for example, after the vehicle M is connected to the charging / discharging facility 80. In the control device 100, first, the acquisition unit 131 determines whether or not a charging / discharging request has been acquired (step S101).

[0044] If it is determined that a V2H request has not been acquired, the acquisition unit 131 repeats the process of step S101. If it is determined that a V2H request has been acquired, the acquisition unit 131 refers to the charge / discharge history stored in the storage unit 120 (step S103) and determines whether charge / discharge of a specified current amount or more has been repeated (step S105).

[0045] If the acquisition unit 131 determines that charging and discharging of a current amount equal to or greater than the specified amount has not been repeated, the control device 100 ends the process shown in Fig. 5. If it determines that charging and discharging of a current amount equal to or greater than the specified amount has been repeated, the acquisition unit 131 determines whether the average discharge rate or the average charge / discharge rate difference is equal to or less than a specified value (step S107). Here, when the lithium metal battery 10 is being discharged, it determines whether the average discharge rate is equal to or less than a first specified value R1, and when the lithium metal battery 10 is being charged, it determines whether the average charge / discharge rate difference is equal to or less than a second specified value R2.

[0046] If the acquisition unit 131 determines that the average discharge rate or the average charge / discharge rate difference is equal to or smaller than a specified value, the determination unit 132 selects the control map (first control map 122 or second reference control map 123) that reduces the charge / discharge current as the recommended charge / discharge control map (step S109).If the acquisition unit 131 determines that the average discharge rate or the average charge / discharge rate difference exceeds a specified value, the determination unit 132 selects the control map (first reference control map 121 or second control map 124) that increases the charge / discharge current as the recommended charge / discharge control map (step S111).

[0047] Next, the determination unit 132 defines the selected recommended charge / discharge control map (step S113), and calculates the charge current or the discharge current by referring to the recommended charge / discharge control map for the discharge rate or the charge / discharge rate difference (step S113). The notification unit 133 generates current value information based on the charge current or the discharge current determined by the determination unit 132, and transfers it to the ECU 200 (step S115). In this way, the control device 100 ends the processing shown in FIG.

[0048] Based on the current value information transmitted by the notification unit 133 of the control device 100, the ECU 200 controls the current adjusting device 70 to adjust the current values ​​of the charging current and discharging current charged to and discharged from the lithium metal battery 10. Under the control of the ECU 200, the lithium metal battery 10 is charged and discharged with the charging current and discharging current of the current values ​​adjusted by the current adjusting device 70.

[0049] The control device 100 of the embodiment determines the charging and discharging details for the lithium metal battery 10 based on the charge and discharge rate during charging and discharging of the lithium metal battery 10. For example, the control device 100 reduces the charging current when the charge rate is equal to or less than a first specified value, and increases the discharging current when the charge and discharge rate exceeds a second specified value. This allows low-rate charging and high-rate discharging to be achieved, thereby effectively suppressing deterioration of the lithium metal battery 10.

[0050] The above-described embodiment can be expressed as follows. a storage medium for storing computer-readable instructions; a processor connected to the storage medium; The processor executes the computer-readable instructions to: The computer Obtaining charge / discharge rate information regarding a charge / discharge rate during charging / discharging of a lithium metal battery having a negative electrode containing lithium; determining charging and discharging details for the lithium metal battery based on the charge and discharge rate information; Control device.

[0051] The above describes the form for carrying out the present invention using an embodiment, but the present invention is not limited to such an embodiment, and various modifications and substitutions can be made within the scope that does not deviate from the gist of the present invention. [Explanation of symbols]

[0052] 10. Lithium metal batteries 11 Positive electrode 11A positive electrode current collector 11B Positive electrode active material layer 12 Negative electrode 12A negative electrode current collector 12B Negative electrode active material layer 13 Electrolytes 13S Separator 20 AC power supply 30 ammeter 40 Electrical Equipment 50 Measuring Instruments 51 Voltage detector 52 Current detector 60 Control Unit 70 Current regulator 100 control device 110 Communications Department 120 Storage section 121 First Reference Control Map 122 First Control Map 123 Second Reference Control Map 124 Second Control Map 125 V2H history 130 Processing section 131 Acquisition Department 132 Decision Section 133 Notification Department M vehicle R1 First specified value R2 Second specified value

Claims

1. an acquisition unit that acquires charge / discharge rate information regarding a charge / discharge rate during charging / discharging of a lithium metal battery having a negative electrode containing lithium; a determination unit that determines charging and discharging details for the lithium metal battery based on the charge and discharge rate information, Control device.

2. the charge / discharge rate information is discharge rate information regarding a discharge rate for the lithium metal battery, The determination unit determines a small charging current as the charging / discharging content when the charging rate included in the charging / discharging rate information is equal to or less than a first specified value. The control device according to claim 1 .

3. the charge / discharge rate information is discharge rate information regarding a current discharged from the lithium metal battery; The determination unit determines a large discharge current as the charge / discharge content when the discharge rate included in the charge / discharge rate information is equal to or less than a second specified value. The control device according to claim 1 .

4. The charge / discharge rate information is information about an average discharge rate or an average charge / discharge rate difference within a specified time. The control device according to claim 1 .

5. the acquisition unit acquires the charge / discharge rate based on information related to a charge / discharge history of the lithium metal battery. The control device according to claim 1 .

6. The lithium metal battery is mounted on a vehicle, The determination unit determines the content of charging / discharging when the vehicle is performing charging / discharging between the vehicle and an external device. The control device according to claim 1 .

7. The computer Obtaining charge / discharge rate information regarding a charge / discharge rate during charging / discharging of a lithium metal battery having a negative electrode containing lithium; determining charging and discharging details for the lithium metal battery based on the charge and discharge rate information; Control method.

8. On the computer, Obtaining charge / discharge rate information regarding a charge / discharge rate during charging / discharging of a lithium metal battery having a negative electrode containing lithium; determining charging and discharging details for the lithium metal battery based on the charge and discharge rate information; program.

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