All-solid-state battery control device

Abstract

To provide an all-solid battery control device for controlling an all-solid battery, the all-solid battery control device being capable of adjusting binding pressure on the all-solid battery depending on an internal resistance value of the all-solid battery.SOLUTION: An all-solid battery control device 1 for controlling binding pressure of an all-solid battery 10 having a solid electrolyte layer 11c comprises: a voltage detector 2 connected to the all-solid battery 10; a current detector 3 connected to the all-solid battery 10; a cell series resistance calculation unit 5a for calculating a cell series resistance value of the all-solid battery 10 on the basis of a detection value of the voltage detector 2 and a detection value of the current detector 3; and a pressure adjustment unit 5b for adjusting binding pressure on the basis of the cell series resistance value.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a control device for an all-solid-state battery.

Background Art

[0002] In recent years, development of all-solid-state batteries using a solid as an electrolyte has been carried out. For example, Patent Document 1 discloses an all-solid-state battery. The all-solid-state battery disclosed in Patent Document 1 includes a positive electrode layer, a negative electrode layer, and a solid electrolyte layer disposed between them. In an all-solid-state battery, it is known that the battery voltage changes according to the pressure acting in the stacking direction of the positive electrode layer, the negative electrode layer, and the solid electrolyte layer. For this reason, Patent Document 1 is provided with pressure control means for adjusting the pressure that constrains the positive electrode layer, the negative electrode layer, and the solid electrolyte layer in the stacking direction. In Patent Document 1, the battery voltage is detected, and the pressure acting in the stacking direction of the positive electrode layer, the negative electrode layer, and the solid electrolyte layer is adjusted according to the battery voltage.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, in an all-solid-state battery, the internal resistance value changes due to the battery temperature and deterioration of the solid electrolyte, and may deviate from the internal resistance value suitable for the all-solid-state battery. In Patent Document 1, the change in the internal resistance value of the all-solid-state battery is not considered, and the pressure that constrains the all-solid-state battery is not adjusted according to the internal resistance value.

[0005] The present invention has been made in view of the above-described problems, and an object of the present invention is to enable adjustment of the constraint pressure on an all-solid-state battery according to the internal resistance value of the all-solid-state battery in an all-solid-state battery control device that controls the all-solid-state battery.

Means for Solving the Problem

[0006] As means for solving the above problems, the present invention adopts the following configuration.

[0007] A first aspect of the present invention is an all-solid-state battery control device that controls the restraint pressure of an all-solid-state battery having a solid electrolyte layer, including a voltage detector connected to the all-solid-state battery, a current detector connected to the all-solid-state battery, an internal resistance calculation unit that calculates an internal resistance value of the all-solid-state battery based on the detection value of the voltage detector and the detection value of the current detector, and a pressure adjustment unit that adjusts the restraint pressure based on the internal resistance value.

[0008] A second aspect of the present invention is, in the first aspect, that the pressure adjustment unit compares the pressure upper limit value, which is the upper limit value of the restraint pressure, with the restraint pressure obtained based on the internal resistance value, and when the restraint pressure obtained based on the internal resistance value exceeds the pressure upper limit value, restricts the restraint pressure of the all-solid-state battery to the pressure upper limit value.

[0009] A third aspect of the present invention is, in the second aspect, that it includes a temperature detector that detects the temperature of the all-solid-state battery, and the pressure adjustment unit changes the pressure upper limit value according to the detection value of the temperature detector.

[0010] A fourth aspect of the present invention is, in any one of the first to third aspects, that it includes an abnormality determination unit that determines the presence or absence of an abnormality in the all-solid-state battery. The abnormality determination unit obtains an estimated internal resistance value, which is the internal resistance value after restraint pressure adjustment estimated from the restraint pressure obtained based on the internal resistance value, obtains an adjusted internal resistance value, which is the internal resistance value of the all-solid-state battery based on the detection value of the voltage detector and the detection value of the current detector after restraint pressure adjustment, and determines the presence or absence of an abnormality in the all-solid-state battery based on the difference between the estimated internal resistance value and the adjusted internal resistance value.

[0011] The fifth aspect of the present invention is, in the fourth aspect described above, provided with a temperature detector for detecting the temperature of the all-solid-state battery, and the abnormality determination unit sets a main abnormality detection processing threshold value for performing detection processing of the presence or absence of the abnormality according to the detection value of the temperature detector, and when the difference between the estimated internal resistance value and the adjusted internal resistance value is equal to or greater than the main abnormality detection processing threshold value, a configuration is adopted in which detection processing of the presence or absence of the abnormality is performed.

[0012] The sixth aspect of the present invention is, in any one of the first to fifth aspects described above, provided with a temperature detector for detecting the temperature of the all-solid-state battery, and when the detection value of the temperature detector is equal to or lower than the temperature required for temperature rise necessary for the all-solid-state battery to rise in temperature, the pressure adjustment unit adopts a configuration in which the restraint pressure on the all-solid-state battery is reduced compared to the restraint pressure based on the internal resistance value.

Advantages of the Invention

[0013] In the present invention, a voltage detector connected to the all-solid-state battery and a current detector connected to the all-solid-state battery are provided. Further, in the present invention, the internal resistance value of the all-solid-state battery is calculated based on the detection value of the voltage detector and the detection value of the current detector, and the restraint pressure is adjusted based on the internal resistance value. Therefore, according to the present invention, in an all-solid-state battery control device that controls an all-solid-state battery, it is possible to adjust the restraint pressure on the all-solid-state battery according to the internal resistance value of the all-solid-state battery.

Brief Description of the Drawings

[0014]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Embodiments for Carrying Out the Invention

[0015] Hereinafter, with reference to the drawings, an embodiment of the all-solid-state battery control device according to the present invention will be described.

[0016] (First Embodiment) FIG. 1 is a block diagram showing a schematic configuration of the all-solid-state battery control device 1 of the present embodiment. The all-solid-state battery control device 1 of the present embodiment monitors the all-solid-state battery 10 and adjusts the restraint pressure acting on the all-solid-state battery 10.

[0017] First, the all-solid-state battery 10 whose restraint pressure is adjusted by the all-solid-state battery control device 1 of the present embodiment will be described. The all-solid-state battery 10 is a secondary battery including a solid electrolyte (a material for forming the negative electrode composite layer 11a, a material for forming the positive electrode composite layer 11b, and a material for forming the solid electrolyte layer 11c). As shown in FIG. 1, the all-solid-state battery 10 includes a plurality of cells 11, a negative electrode current collector 12, a positive electrode current collector 13, a pressurizing mechanism 14, and a battery case 15.

[0018] Each cell 11 has a negative electrode composite layer 11a, a positive electrode composite layer 11b, and a solid electrolyte layer 11c. These negative electrode composite layer 11a, positive electrode composite layer 11b, and solid electrolyte layer 11c are laminated.

[0019] Note that the installation posture of the all-solid-state battery 10 is not particularly limited. However, in the following description, for the sake of convenience of explanation, the stacking direction of the negative electrode composite material layer 11a, the positive electrode composite material layer 11b, and the solid electrolyte layer 11c is set as the vertical direction. In the all-solid-state battery 10 shown in FIG. 1, the negative electrode composite material layer 11a, the positive electrode composite material layer 11b, and the solid electrolyte layer 11c are stacked in the order of the negative electrode composite material layer 11a, the solid electrolyte layer 11c, and the positive electrode composite material layer 11b from the lower side.

[0020] The negative electrode composite material layer 11a is a layer formed by mixing, for example, a granular negative electrode active material and, for example, a powdery solid electrolyte. For example, the negative electrode composite material layer 11a is formed by pressure-molding a mixture of a negative electrode active material and a solid electrolyte.

[0021] The negative electrode active material is not particularly limited, but for example, graphite or carbon can be used. Also, the solid electrolyte contained in the negative electrode composite material layer 11a is not particularly limited, but a sulfide-based electrolyte or an oxide-based electrolyte can be used. Note that the negative electrode composite material layer 11a may contain a conductive auxiliary material or a binder.

[0022] The positive electrode composite material layer 11b is disposed opposite to the negative electrode composite material layer 11a with the solid electrolyte layer 11c interposed therebetween. This positive electrode composite material layer 11b is a layer formed by mixing, for example, a granular positive electrode active material and, for example, a powdery solid electrolyte. For example, the positive electrode composite material layer 11b is formed by pressure-molding a mixture of a positive electrode active material and a solid electrolyte.

[0023] The positive electrode active material is not particularly limited, but for example, LiCoO2, LiNiO2, LiMn2O4, LiCo 0.5 can be used. Also, the solid electrolyte contained in the positive electrode composite material layer 11b is not particularly limited, but a sulfide-based electrolyte or an oxide-based electrolyte can be used. Note that the positive electrode composite material layer 11b may contain a conductive auxiliary material or a binder.

[0024] The solid electrolyte layer 11c is interposed between the negative electrode composite layer 11a and the positive electrode composite layer 11b. This solid electrolyte layer 11c is formed of, for example, granular solid electrolyte. For example, the solid electrolyte layer 11c is formed by pressure-molding granular solid electrolyte. The solid electrolyte is not particularly limited, but sulfide-based electrolytes or oxide-based electrolytes can be used.

[0025] As shown in FIG. 1, the all-solid-state battery 10 includes a plurality of cells 11 stacked in the vertical direction. These cells 11 are electrically connected in series. Among the plurality of cells 11, a negative electrode current collector 12 is connected to the negative electrode composite layer 11a of the lowermost cell 11. Also, a positive electrode current collector 13 is connected to the positive electrode composite layer 11b of the uppermost cell 11 among the plurality of cells 11.

[0026] One end of the negative electrode current collector 12 is connected to the negative electrode composite layer 11a of the cell 11 inside the battery case 15, and the other end is drawn out to the outside of the battery case 15. The portion of the negative electrode current collector 12 drawn out to the outside of the battery case 15 serves as the negative electrode terminal of the all-solid-state battery 10. The material for forming the negative electrode current collector 12 is not particularly limited, but for example, copper can be used.

[0027] One end of the positive electrode current collector 13 is connected to the positive electrode composite layer 11b of the cell 11 inside the battery case 15, and the other end is drawn out to the outside of the battery case 15. The portion of the positive electrode current collector 13 drawn out to the outside of the battery case 15 serves as the positive electrode terminal of the all-solid-state battery 10. The material for forming the positive electrode current collector 13 is not particularly limited, but for example, aluminum can be used.

[0028] The pressing mechanism 14 is disposed above the plurality of stacked cells 11 and generates a pressure applied to these cells 11. The pressure applied to the plurality of cells 11 from this pressing mechanism 14 is referred to as the restraint pressure.

[0029] As shown in FIG. 1, this pressurizing mechanism 14 includes a pressure plate 14a and a pressurizing piston 14b. The pressure plate 14a is a plate member that abuts against the upper surface of the uppermost cell among the plurality of cells 11 from above. The pressure plate 14a is formed, for example, in a size that covers the entire cell 11 when viewed from above.

[0030] The pressurizing piston 14b is connected to the pressure plate 14a from above and is fixed to the battery case 15. The pressurizing piston 14b generates a pressing force that presses the pressure plate 14a from above.

[0031] Due to this pressing force, a restraint pressure for pressing the cell 11 is generated. The pressurizing piston 14b is connected to a control unit 5 described later and adjusts the pressing force under the control of the control unit 5. That is, under the control of the control unit 5, by adjusting the pressing force of the pressurizing piston 14b, the restraint pressure acting on the cell 11 is adjusted.

[0032] The battery case 15 is a container that houses a plurality of cells 11. The battery case 15 also houses the pressurizing mechanism 14. Further, the battery case 15 is penetrated in a state where the negative electrode current collector 12 and the positive electrode current collector 13 are sealed.

[0033] Such a all-solid-state battery 10 is connected to a load such as a motor via, for example, a power conversion device (not shown). The all-solid-state battery 10 supplies the power charged in the cell 11 to the load via the power conversion device. Further, the all-solid-state battery 10 stores the regenerative power supplied from the load via the power conversion device and the power supplied from an external power source via the power conversion device.

[0034] As shown in FIG. 1, the all-solid-state battery control device 1 of the present embodiment includes a voltage detector 2, a current detector 3, an AC generator 4, and a control unit 5. The voltage detector 2 is connected to the negative electrode terminal (negative electrode current collector 12) and the positive electrode terminal (positive electrode current collector 13) of the all-solid-state battery 10 via wiring. The voltage detector 2 detects the potential difference between the negative electrode terminal and the positive electrode terminal and outputs the detected value.

[0035] In this embodiment, an AC signal for detecting the cell series resistance value is applied from the AC generator 4 to the all-solid-state battery 10. The voltage detector 2 detects the potential difference between the negative electrode terminal and the positive electrode terminal when an AC signal is applied to the all-solid-state battery 10. Further, the voltage detector 2 can also detect the battery voltage of the all-solid-state battery 10 in a state where no AC signal is applied.

[0036] The current detector 3 is connected to the negative electrode terminal of the all-solid-state battery 10 via a wiring. This current detector 3 detects the current value flowing through the negative electrode terminal of the all-solid-state battery 10 and outputs the detected value. That is, the current detector 3 detects the current value of the negative electrode terminal when an AC signal is applied to the all-solid-state battery 10. Note that the current detector 3 may be connected to the positive electrode terminal of the all-solid-state battery 10 via a wiring. Further, the current detector 3 can also detect the output current of the all-solid-state battery 10 in a state where no AC signal is applied.

[0037] The AC generator 4 is connected to the negative electrode terminal (negative electrode current collector 12) and the positive electrode terminal (positive electrode current collector 13) of the all-solid-state battery 10 via a wiring. This AC generator 4 is connected to the control unit 5 and generates an AC signal to be applied to the all-solid-state battery 10 under the control of the control unit 5 and supplies it to the all-solid-state battery 10.

[0038] Note that when the all-solid-state battery 10 is connected to a power converter, for example, it is also possible to supply an AC signal from the power converter to the all-solid-state battery 10. In such a case, it is also possible to omit the AC generator 4 from the all-solid-state battery control device 1 of this embodiment.

[0039] Further, in this embodiment, the cell series resistance value is obtained using a so-called AC method. However, it is also possible to obtain the cell series resistance value using a so-called DC method. Thus, when obtaining the cell series resistance value using the DC method, it is also possible to omit the AC generator 4 from the all-solid-state battery control device 1 of this embodiment.

[0040] The control unit 5 monitors the state of the all-solid-state battery 10 and adjusts the restraint pressure of the all-solid-state battery 10. The control unit 5 is connected to the voltage detector 2, the current detector 3, and the AC generator 4.

[0041] Further, the control unit 5 is formed by a computer device or the like including a storage device, an arithmetic device, and the like. The storage device includes memories such as ROM (Read Only Memory) and RAM (Random Access Memory), and storages such as HDD (Hard Disk Drive) and SSD (Solid State Drive). The arithmetic device performs arithmetic operations based on programs, operation signals, and the like. This arithmetic unit includes an interface circuit, a CPU (Central Processing Unit), and the like.

[0042] In the present embodiment, the control unit 5 has a functional unit realized by the cooperation of the above-described hardware such as the storage device and the arithmetic device, and programs, data, and the like stored in the storage device. As shown in FIG. 1, in the present embodiment, the control unit 5 includes, as functional units, a cell series resistance calculation unit 5a (internal resistance calculation unit), a pressure adjustment unit 5b, an abnormality determination unit 5c, and a storage unit 5d.

[0043] The cell series resistance calculation unit 5a calculates the cell series resistance value (internal resistance value) of the all-solid-state battery based on the detection value of the voltage detector 2 (hereinafter referred to as the detected voltage value) and the detection value of the current detector 3 (hereinafter referred to as the detected current value).

[0044] The cell series resistance calculation unit 5a inputs an output command of an AC signal for calculating the cell series resistance value to the AC generator 4 at the timing of calculating the cell series resistance. Further, the cell series resistance calculation unit 5a calculates the cell series resistance value based on the detected voltage value and the detected current value obtained in a state where the AC signal is supplied to the all-solid-state battery 10.

[0045] For example, more specifically, the cell series resistance calculation unit 5a calculates the cell series resistance value by dividing the change value of the detected voltage value at a predetermined time by the change value of the detected current value at the predetermined time.

[0046] The pressure adjustment unit 5b adjusts the constraint pressure based on the cell series resistance value calculated by the cell series resistance calculation unit 5a. For example, the pressure adjustment unit 5b calculates the constraint pressure for setting a target cell series resistance value (hereinafter referred to as the target cell series resistance value) based on a relationship table or the like showing the change in the cell series resistance value with respect to the change in the constraint pressure. The pressure adjustment unit 5b adjusts the constraint pressure by controlling the pressurizing mechanism 14 so that the constraint pressure of the all-solid-state battery 10 becomes the calculated constraint pressure.

[0047] In the present embodiment, the pressure adjustment unit 5b compares the constraint pressure obtained based on the target cell series resistance value with the pressure upper limit value that is the upper limit value of the constraint pressure. Here, when the constraint pressure obtained based on the target cell series resistance value exceeds the pressure upper limit value, the pressure adjustment unit 5b limits the constraint pressure of the all-solid-state battery 10 to the pressure upper limit value.

[0048] The abnormality determination unit 5c obtains an estimated cell series resistance value (estimated internal resistance value) as the cell series resistance value after the constraint pressure adjustment estimated from the constraint pressure obtained based on the target cell series resistance value. When the constraint pressure obtained based on the target cell series resistance value is the constraint pressure obtained so that the actual cell series resistance value becomes the target cell series resistance value, the estimated cell series resistance value becomes the target cell series resistance value on the condition that the constraint pressure obtained based on the target cell series resistance value does not exceed the pressure upper limit value.

[0049] Further, the abnormality determination unit 5c obtains the adjusted cell series resistance value (adjusted internal resistance value) of the all-solid-state battery 10 based on the detected voltage value and the detected current value after the constraint pressure adjustment. Furthermore, the abnormality determination unit 5c determines the presence or absence of an abnormality in the all-solid-state battery 10 based on the difference between the estimated cell series resistance value and the adjusted cell series resistance value.

[0050] For example, when the cell 11 or the like is normal and no abnormality occurs in the all-solid-state battery 10, even if there is an error, the adjusted cell series resistance value will be close to the estimated cell series resistance value. On the other hand, when the difference between the estimated cell series resistance value and the adjusted cell series resistance value is large, it is considered that an abnormality may have occurred in one or a plurality of cells 11. Therefore, when the difference between the estimated cell series resistance value and the adjusted cell series resistance value is large, it is desirable to determine that the all-solid-state battery 10 is abnormal or to execute an abnormality detection process for detecting an abnormality in the all-solid-state battery 10.

[0051] In the present embodiment, the abnormality determination unit 5c compares the required abnormality detection process threshold value for determining whether to execute an abnormality detection process for detecting an abnormality in the all-solid-state battery 10 with the difference between the estimated cell series resistance value and the adjusted cell series resistance value. The abnormality determination unit 5c executes the abnormality detection process when the difference between the estimated cell series resistance value and the adjusted cell series resistance value is equal to or greater than the required abnormality detection process threshold value.

[0052] The storage unit 5d stores programs and various data. For example, the storage unit 5d stores a relational table showing the change in the cell series resistance value with respect to the change in the constraint pressure, a target cell series resistance value, a pressure upper limit value, a required abnormality detection process threshold value, and the like.

[0053] Subsequently, the operation of the all-solid-state battery control device 1 of the present embodiment will be described with reference to the flowchart of FIG. 2. In the following description, the main body of the operation is the control unit 5.

[0054] As shown in FIG. 2, first, the calculation of the cell series resistance value is performed (step S1). Here, the cell series resistance value is calculated by the cell series resistance calculation unit 5a of the control unit 5. The cell series resistance calculation unit 5a causes the AC generator 4 to output an AC signal.

[0055] Such an AC signal is input to the all-solid-state battery 10. The cell series resistance calculation unit 5a calculates the cell series resistance value of the all-solid-state battery 10 based on the detected voltage value and the detected current value while the AC signal is being supplied to the all-solid-state battery 10.

[0056] In this embodiment, the cell series resistance calculation unit 5a calculates the cell series resistance value by dividing the change value of the detected voltage value at a predetermined time by the change value of the detected current value at the predetermined time.

[0057] Subsequently, as shown in FIG. 2, the confinement pressure is calculated (step S2). Here, the confinement pressure is calculated by the pressure adjustment unit 5b of the control unit 5. The pressure adjustment unit 5b calculates the confinement pressure for setting the target cell series resistance value stored in the storage unit 5d based on the relationship table (table showing the change in the cell series resistance value with respect to the change in the confinement pressure) stored in the storage unit 5d and the cell series resistance value calculated in step S1.

[0058] Subsequently, as shown in FIG. 2, it is determined whether or not the confinement pressure calculated in step S2 exceeds the pressure upper limit value (step S3). Here, the pressure adjustment unit 5b determines whether or not the calculated confinement pressure exceeds the pressure upper limit value.

[0059] The pressure adjustment unit 5b compares the confinement pressure obtained based on the cell series resistance value (the confinement pressure calculated in step S2) with the pressure upper limit value which is the upper limit value of the confinement pressure. Then, when the calculated confinement pressure is greater than the pressure upper limit value, the pressure adjustment unit 5b determines that the calculated confinement pressure exceeds the pressure upper limit value. On the other hand, when the calculated confinement pressure is less than or equal to the pressure upper limit value, the pressure adjustment unit 5b determines that the calculated confinement pressure does not exceed the pressure upper limit value.

[0060] In step S3, when it is determined that the calculated confinement pressure exceeds the pressure upper limit value, the pressure adjustment unit 5b limits the confinement pressure to the pressure upper limit value (step S4). On the other hand, in step S3, when it is determined that the calculated confinement pressure does not exceed the pressure upper limit value, the pressure adjustment unit 5b adjusts the confinement pressure (step S5).

[0061] When step S4 is completed, the process proceeds to step S5. In step S5, the pressure adjustment unit 5b adjusts the restraint pressure by controlling the pressurizing mechanism 14 so that the restraint pressure of the all-solid-state battery 10 becomes the required restraint pressure.

[0062] Subsequently, the estimated cell series resistance value is calculated (step S6). Here, the abnormality determination unit 5c of the control unit 5 calculates the estimated cell series resistance value. The abnormality determination unit 5c estimates the cell series resistance value after the restraint pressure adjustment, for example, from the restraint pressure calculated in step S2 and a relational table showing the change in the cell series resistance value with respect to the change in the restraint pressure. The abnormality determination unit 5c sets the cell series resistance value after the restraint pressure adjustment obtained by this estimation as the estimated cell series resistance.

[0063] Note that this step S6 may be performed before step S5. That is, when it is determined that the restraint pressure calculated in step S3 exceeds the pressure upper limit value, step S6 may be performed between step S4 and step S5. Also, when it is determined that the restraint pressure calculated in step S3 does not exceed the pressure upper limit value, step S6 may be performed between step S3 and step S5.

[0064] Subsequently, the adjusted cell series resistance value is calculated (step S7). Here, for example, the cell series resistance calculation unit 5a of the control unit 5 calculates the adjusted cell series resistance value. The adjusted cell series resistance value is the cell series resistance obtained based on the detected voltage value and the detected current value after the restraint pressure is adjusted in step S5.

[0065] Here too, the cell series resistance calculation unit 5a causes the AC generator 4 to output an AC signal in the same manner as in step S1. The cell series resistance calculation unit 5a calculates the adjusted cell series resistance value by dividing the change value of the detected voltage value in a predetermined time by the change value of the detected current value in the predetermined time.

[0066] Subsequently, it is determined whether or not the difference between the estimated cell series resistance value and the adjusted cell series resistance value is equal to or greater than the abnormal detection processing threshold (step S8). Here, for example, the abnormality determination unit 5c determines whether or not the difference between the estimated cell series resistance value and the adjusted cell series resistance value is equal to or greater than the abnormal detection processing threshold.

[0067] The abnormality determination unit 5c compares the abnormal detection processing threshold for determining the necessity of executing the abnormal detection process for detecting the abnormality of the all-solid-state battery 10 with the difference between the estimated cell series resistance value and the adjusted cell series resistance value. Thereby, the abnormality determination unit 5c executes step S8.

[0068] When the difference between the estimated cell series resistance value and the adjusted cell series resistance value is equal to or greater than the abnormal detection processing threshold, the abnormal detection process for detecting the abnormality of the all-solid-state battery 10 is executed (step S9). Here, for example, the abnormality determination unit 5c executes the abnormal detection process for detecting the abnormality of the all-solid-state battery 10.

[0069] When the abnormal detection process is executed, the presence or absence of an abnormality is notified to an operator or the like. For example, if no abnormality is found as a result of executing the abnormal detection process, it may return to step S1 again. Also, even if no abnormality is found as a result of executing the normal detection process, it is possible to shift to step S1 without an instruction from the operator.

[0070] In step S8, when it is determined that the difference between the estimated cell series resistance value and the adjusted cell series resistance value is not equal to or greater than the abnormal detection processing threshold, for example, it returns to step S1 again. Here, a signal indicating no abnormality is input from the abnormality determination unit 5c to the cell series resistance calculation unit 5a, and the cell series resistance calculation unit 5a executes step S1 again.

[0071] The all-solid-state battery control device 1 of the present embodiment as described above controls the restraint pressure of the all-solid-state battery 10 having the solid electrolyte layer 11c. Further, the all-solid-state battery control device 1 of the present embodiment includes a voltage detector 2 connected to the all-solid-state battery 10, a current detector 3 connected to the all-solid-state battery 10, a cell series resistance calculation unit 5a, and a pressure adjustment unit 5b. The cell series resistance calculation unit 5a calculates the cell series resistance value of the all-solid-state battery 10 based on the detection value of the voltage detector 2 and the detection value of the current detector 3. Further, the pressure adjustment unit 5b adjusts the restraint pressure based on the cell series resistance value.

[0072] As described above, the all-solid-state battery control device 1 of the present embodiment includes a voltage detector 2 connected to the all-solid-state battery 10 and a current detector 3 connected to the all-solid-state battery 10. Further, in the all-solid-state battery control device 1 of the present embodiment, the cell series resistance value of the all-solid-state battery 10 is calculated based on the detection value of the voltage detector 2 and the detection value of the current detector 3, and the restraint pressure is adjusted based on the cell series resistance value. Therefore, according to the all-solid-state battery control device 1 of the present embodiment, it is possible to adjust the restraint pressure on the all-solid-state battery 10 according to the cell series resistance value of the all-solid-state battery 10.

[0073] Further, in the all-solid-state battery control device 1 of the present embodiment, the pressure adjustment unit 5b compares the pressure upper limit value, which is the upper limit value of the restraint pressure, with the restraint pressure obtained based on the cell series resistance value. Further, when the restraint pressure obtained based on the cell series resistance value exceeds the pressure upper limit value, the pressure adjustment unit 5b limits the restraint pressure of the all-solid-state battery 10 to the pressure upper limit value. According to the all-solid-state battery control device 1 of the present embodiment as described above, it is possible to prevent a restraint pressure exceeding the pressure upper limit value from acting on the cell 11.

[0074] Further, in the all-solid-state battery control device 1 of the present embodiment, an abnormality determination unit 5c for determining the presence or absence of an abnormality in the all-solid-state battery 10 is provided. The abnormality determination unit 5c obtains an estimated cell series resistance value, which is the cell series resistance value after restraint pressure adjustment estimated from the restraint pressure obtained based on the cell series resistance value. Further, the abnormality determination unit 5c obtains an adjusted cell series resistance value, which is the cell series resistance value of the all-solid-state battery 10, based on the detection value of the voltage detector 2 and the detection value of the current detector 3 after the restraint pressure adjustment. Further, the abnormality determination unit 5c determines the presence or absence of an abnormality in the all-solid-state battery 10 based on the difference between the estimated cell series resistance value and the adjusted cell series resistance value.

[0075] When the difference between the estimated cell series resistance value and the adjusted cell series resistance value is large, it is considered that an abnormality may have occurred in one or more of the cells 11. According to the all-solid-state battery control device 1 of the present embodiment, when the difference between the estimated cell series resistance value and the adjusted cell series resistance value is large, an abnormality detection process for detecting an abnormality in the all-solid-state battery 10 is executed. Therefore, it becomes possible to quickly grasp the abnormality of the cell 11.

[0076] (Second Embodiment) Next, a second embodiment of the present invention will be described. In the description of the present embodiment, the description of the same parts as those in the first embodiment above will be omitted or simplified.

[0077] FIG. 3 is a block diagram showing a schematic configuration of the all-solid-state battery control device 1A of the present embodiment. As shown in FIG. 3, the all-solid-state battery control device 1A of the present embodiment further includes a temperature detector 6 with respect to the all-solid-state battery control device 1 of the first embodiment.

[0078] The temperature detector 6 detects the temperature of the all-solid-state battery 10 and outputs the detected value (hereinafter referred to as the detected temperature value). The temperature detector 6 is installed so as to be close to or in contact with the all-solid-state battery 10.

[0079] In the all-solid-state battery 10, when the temperature of the all-solid-state battery 10 is relatively high, the solid electrolyte layer 11c and the like expand. Also, in the all-solid-state battery 10, when the temperature of the all-solid-state battery 10 is relatively low, the solid electrolyte layer 11c and the like contract.

[0080] Due to such expansion and contraction of the solid electrolyte layer 11c and the like, the suitable target cell series resistance value also changes. For example, as the temperature of the all-solid-state battery 10 increases, it is preferable to decrease the target cell series resistance value.

[0081] Therefore, in the all-solid-state battery control device 1A of the present embodiment, a table showing the relationship between the temperature of the all-solid-state battery 10 and the target cell series resistance value obtained in advance (hereinafter referred to as the temperature-target cell series resistance relationship table) is stored in the storage unit 5d.

[0082] Also, due to the expansion and contraction of the solid electrolyte layer 11c and the like due to the temperature of the all-solid-state battery 10, the pressure upper limit value also changes. Therefore, in the all-solid-state battery control device 1A of the present embodiment, a table showing the relationship between the temperature of the all-solid-state battery 10 and the pressure upper limit value (hereinafter referred to as the temperature-pressure upper limit value relationship table) is stored in the storage unit 5d.

[0083] For example, the pressure adjustment unit 5b sets the target cell series resistance value from the detected temperature value input from the temperature detector 6 based on the temperature-target cell series resistance relationship table. The pressure adjustment unit 5b calculates the restraint pressure based on this target cell series resistance value. Also, the pressure adjustment unit 5b adjusts the restraint pressure by controlling the pressurizing mechanism 14 so that the restraint pressure of the all-solid-state battery 10 becomes the calculated restraint pressure.

[0084] Further, the pressure adjustment unit 5b sets a pressure upper limit value from the detected temperature value input from the temperature detector 6 based on the temperature-pressure upper limit value relationship table. Further, the pressure adjustment unit 5b compares the restraint pressure obtained based on the target cell series resistance value with the pressure upper limit value that is the upper limit value of the restraint pressure. Here, when the restraint pressure obtained based on the cell series resistance value exceeds the pressure upper limit value, the pressure adjustment unit 5b limits the restraint pressure of the all-solid-state battery 10 to the pressure upper limit value.

[0085] FIG. 4 is a flowchart for explaining the operation of the all-solid-state battery control device 1A of the present embodiment.

[0086] As shown in FIG. 4, in the all-solid-state battery control device 1A of the present embodiment, the temperature of the all-solid-state battery 10 is acquired before step S1 of the first embodiment (step S10). Here, the pressure adjustment unit 5b acquires the temperature detection value output from the temperature detector 6 as the temperature of the all-solid-state battery 10.

[0087] Subsequently, when calculating the restraint pressure in step S2, the pressure adjustment unit 5b sets a target cell series resistance value from the detected temperature value input from the temperature detector 6 based on the temperature-target cell series resistance relationship table.

[0088] Furthermore, the pressure adjustment unit 5b calculates a restraint pressure for setting the target cell series resistance value stored in the storage unit 5d based on the relationship table (table showing the change in the cell series resistance value with respect to the change in the restraint pressure) stored in the storage unit 5d and the cell series resistance value calculated in step S1, using the set target cell series resistance value.

[0089] Also, as shown in FIG. 4, in the all-solid-state battery control device 1A of the present embodiment, before step S3 of the first embodiment, the setting of the pressure upper limit value is performed (step S11). Here, the pressure adjustment unit 5b obtains the pressure upper limit value from the detected temperature value based on the temperature-pressure upper limit value relationship table stored in the storage unit 5d.

[0090] Thereafter, the pressure adjustment unit 5b performs step S3. Here, the pressure adjustment unit 5b determines whether or not the restraint pressure calculated in step S2 exceeds the pressure upper limit value using the pressure upper limit value set in step S11.

[0091] In the all-solid-state battery control device 1A of the present embodiment as described above, a temperature detector 6 for detecting the temperature of the all-solid-state battery 10 is provided. Further, the pressure adjustment unit 5b sets a target cell series resistance value (restraint pressure) based on the temperature of the all-solid-state battery 10. Therefore, it becomes possible to set a target cell series resistance value (restraint pressure) suitable according to the temperature of the all-solid-state battery 10.

[0092] Also, in the all-solid-state battery control device 1A of the present embodiment, a temperature detector 6 for detecting the temperature of the all-solid-state battery 10 is provided. Further, the pressure adjustment unit 5b changes the pressure upper limit value according to the detection value of the temperature detector 6. Therefore, it is possible to set a pressure upper limit value suitable according to the temperature of the all-solid-state battery 10.

[0093] (Third Embodiment) Next, a third embodiment of the present invention will be described. In the description of the present embodiment, the description of the same parts as those in the first embodiment or the second embodiment will be omitted or simplified.

[0094] The all-solid-state battery control device of the present embodiment includes a temperature detector 6 in the same manner as in the second embodiment. In the all-solid-state battery 10, when the temperature of the all-solid-state battery 10 is relatively high, the solid electrolyte layer 11c and the like expand.

[0095] Also, in the all-solid-state battery 10, when the temperature of the all-solid-state battery 10 is relatively low, the solid electrolyte layer 11c and the like contract. It is preferable to change the abnormal detection processing threshold according to the expansion and contraction of the solid electrolyte layer 11c and the like.

[0096] Therefore, in the all-solid-state battery control device of the present embodiment, a table showing the relationship between the temperature of the all-solid-state battery 10 and the threshold value for abnormal detection processing (hereinafter referred to as the temperature-abnormal detection processing threshold value relationship table) is stored in the storage unit 5d.

[0097] The abnormality determination unit 5c sets the threshold value for abnormal detection processing from the detected temperature value input from the temperature detector 6 based on the temperature-abnormal detection processing relationship table. The abnormality determination unit 5c executes the abnormal detection processing when the difference between the estimated cell series resistance value and the adjusted cell series resistance value is equal to or greater than this threshold value for abnormal detection processing.

[0098] FIG. 5 is a flowchart for explaining the operation of the all-solid-state battery control of the present embodiment. As shown in this figure, in the all-solid-state battery control device of the present embodiment, as can be seen by comparison with the operation of the all-solid-state battery control device 1A of the second embodiment shown in FIG. 4, before step S8, the threshold value for abnormal detection processing is set (step S20).

[0099] Here, the abnormality determination unit 5c sets the threshold value for abnormal detection processing. The abnormality determination unit 5c obtains the pressure upper limit value from the threshold value for abnormal detection processing based on the temperature-abnormal detection processing threshold value relationship table stored in the storage unit 5d.

[0100] Thereafter, the abnormality determination unit 5c determines whether or not the difference between the estimated cell series resistance value and the adjusted cell series resistance value is equal to or greater than the threshold value for abnormal detection processing set in step S20 (step S8).

[0101] In the all-solid-state battery control device of the present embodiment as described above, a temperature detector 6 for detecting the temperature of the all-solid-state battery 10 is provided. Further, the abnormality determination unit 5c sets the threshold value for abnormal detection processing based on the temperature of the all-solid-state battery 10.

[0102] Further, when the difference between the estimated cell series resistance value and the adjusted cell series resistance value becomes equal to or greater than the threshold value for detecting a critical abnormality, the abnormality determination unit 5c performs a detection process for the presence or absence of an abnormality. Therefore, it becomes possible to set a threshold value for detecting a critical abnormality suitable according to the temperature of the all-solid-state battery 10.

[0103] (Fourth Embodiment) Next, a fourth embodiment of the present invention will be described. In the description of this embodiment, parts similar to those in the first embodiment or the second embodiment are omitted or simplified in their descriptions.

[0104] When the temperature of the all-solid-state battery 10 is decreasing, the output may not be stable. Therefore, it is preferable to warm the all-solid-state battery 10 until the temperature of the all-solid-state battery 10 reaches a predetermined temperature. For this reason, in the all-solid-state battery control device of this embodiment, the storage unit 5d stores the detection value of the temperature detector as the temperature required for temperature increase necessary for the temperature increase of the all-solid-state battery 10.

[0105] The pressure adjustment unit 5b compares the detected temperature value with the temperature required for temperature increase. As a result, when the detected temperature value is equal to or lower than the temperature required for temperature increase, the pressure adjustment unit 5b reduces the restraint pressure on the all-solid-state battery 10 compared to the restraint pressure based on the target cell series resistance value.

[0106] By thus reducing the restraint pressure, the cell series resistance increases, and the amount of heat generated in the all-solid-state battery 10 increases. Therefore, when the temperature of the all-solid-state battery 10 is decreasing, it becomes possible to actively warm the all-solid-state battery 10 by reducing the restraint pressure.

[0107] FIG. 6 is a flowchart for explaining the operation of the all-solid-state battery control of this embodiment. As shown in this figure, in the all-solid-state battery control device of this embodiment, as can be understood by comparison with the operation of the all-solid-state battery control device 1A of the second embodiment shown in FIG. 4, before step S2, it is determined whether the detected temperature value is equal to or higher than the temperature required for temperature increase (step S30).

[0108] In step S30, when the pressure adjustment unit 5b determines that the detected temperature value is not equal to or higher than the temperature required for temperature increase, it proceeds to step S3. On the other hand, in step S30, when it is determined that the detected temperature value is equal to or higher than the temperature required for temperature increase, the restraint pressure is adjusted to be lower than the restraint pressure corresponding to the target cell series resistance value (step S31). Thereafter, it returns to step S1 again.

[0109] In the all-solid-state battery control device of the present embodiment as described above, a temperature detector 6 for detecting the temperature of the all-solid-state battery 10 is provided. Further, the abnormality determination unit 5c sets the abnormal detection processing threshold value based on the temperature of the all-solid-state battery 10.

[0110] Also, when the detected value of the temperature detector by the pressure adjustment unit 5b is equal to or lower than the temperature required for temperature increase of the all-solid-state battery 10, the restraint pressure on the all-solid-state battery 10 is reduced compared to the restraint pressure based on the cell series resistance value. Therefore, it becomes possible to heat the all-solid-state battery 10 as needed.

[0111] As described above, the preferred embodiments of the present invention have been described with reference to the accompanying drawings. Needless to say, the present invention is not limited to the above embodiments. The various shapes, combinations, etc. of the constituent members shown in the above-described embodiments are examples, and various modifications can be made based on design requirements and the like without departing from the spirit of the present invention.

[0112] For example, in the above embodiment, the configuration in which the control unit 5 includes the abnormality determination unit 5c as a functional unit has been described. However, the present invention is not limited to this. For example, it is also possible to adopt a configuration in which the control unit 5 does not include the abnormality determination unit 5c as a functional unit. That is, it is also possible to adopt a configuration in which the control unit 5 does not perform the abnormality determination process. In such a case, for example, the steps S6, S7, S8, and S9 shown in the flowchart of FIG. 1 and the like are not performed.

Description of Reference Numerals

[0113] 1... All-solid-state battery control device, 1A... All-solid-state battery control device, 2... Voltage detector, 3... Current detector, 4... AC generator, 5... Control unit, 5a... Cell series resistance calculation unit (internal resistance calculation unit), 5b... Pressure adjustment unit, 5c... Abnormality determination unit, 5d... Memory unit, 6... Temperature detector, 10... All-solid-state battery, 11... Cell, 11a... Negative electrode composite layer, 11b... Positive electrode composite layer, 11c... Solid electrolyte layer, 12... Negative electrode current collector, 13... Positive electrode current collector, 14... Pressurizing mechanism, 14a... Pressurizing plate, 14b... Pressurizing piston, 15... Battery case

Claims

1. A all-solid-state battery control device for controlling the restraint pressure of an all-solid-state battery having a solid electrolyte layer, comprising a voltage detector connected to the all-solid-state battery, a current detector connected to the all-solid-state battery, an internal resistance calculation unit that calculates an internal resistance value of the all-solid-state battery based on a detection value of the voltage detector and a detection value of the current detector, a pressure adjustment unit that adjusts the restraint pressure based on the internal resistance value, and a temperature detector that detects the temperature of the all-solid-state battery ; The pressure adjustment unit compares a pressure upper limit value that is an upper limit value of the restraint pressure with the restraint pressure obtained based on the internal resistance value, limits the restraint pressure of the all-solid-state battery to the pressure upper limit value when the restraint pressure obtained based on the internal resistance value exceeds the pressure upper limit value, and changes the pressure upper limit value according to a detection value of the temperature detector A all-solid-state battery control device characterized by the above.

2. A all-solid-state battery control device for controlling the restraint pressure of an all-solid-state battery having a solid electrolyte layer, comprising a voltage detector connected to the all-solid-state battery, a current detector connected to the all-solid-state battery, an internal resistance calculation unit that calculates an internal resistance value of the all-solid-state battery based on a detection value of the voltage detector and a detection value of the current detector, a pressure adjustment unit that adjusts the restraint pressure based on the internal resistance value, and an abnormality determination unit that determines the presence or absence of an abnormality in the all-solid-state battery ; The abnormality determination unit obtains an estimated internal resistance value, which is an internal resistance value after restraint pressure adjustment estimated from the restraint pressure obtained based on the internal resistance value, obtains an adjusted internal resistance value, which is an internal resistance value of the all-solid-state battery based on a detection value of the voltage detector and a detection value of the current detector after restraint pressure adjustment, and determines the presence or absence of an abnormality in the all-solid-state battery based on a difference between the estimated internal resistance value and the adjusted internal resistance value A all-solid-state battery control device characterized by the above.

3. Comprising a temperature detector that detects the temperature of the all-solid-state battery, The abnormality determination unit sets a main abnormality detection processing threshold value for performing a detection process for the presence or absence of an abnormality according to a detection value of the temperature detector, and performs a detection process for the presence or absence of an abnormality when a difference between the estimated internal resistance value and the adjusted internal resistance value is equal to or greater than the main abnormality detection processing threshold value The all-solid-state battery control device according to Claim 2, characterized by the above.

4. A all-solid-state battery control device for controlling the restraint pressure of an all-solid-state battery having a solid electrolyte layer, comprising a voltage detector connected to the all-solid-state battery, A current detector connected to the all-solid-state battery, an internal resistance calculation unit that calculates an internal resistance value of the all-solid-state battery based on a detection value of the voltage detector and a detection value of the current detector, a pressure adjustment unit that adjusts the restraint pressure based on the internal resistance value, and a temperature detector that detects the temperature of the all-solid-state battery are provided, wherein when the detection value of the temperature detector is equal to or lower than a temperature-raising required temperature at which the all-solid-state battery needs to be heated up, the pressure adjustment unit reduces the restraint pressure on the all-solid-state battery compared to the restraint pressure based on the internal resistance value An all-solid-state battery control device characterized by the above.

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