JP7710342B2 - All-solid-state battery control device - Google Patents

Description

The present invention relates to an all-solid-state battery control device.

In recent years, all-solid-state batteries using solids as electrolytes have been developed. 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. It is known that in all-solid-state batteries, the battery voltage changes depending on 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 includes a pressure control means for adjusting the pressure that restrains 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 depending on the battery voltage.

JP 2010-205479 A

However, in an all-solid-state battery, the internal resistance value changes due to the battery temperature or degradation of the solid electrolyte, and may deviate from the internal resistance value suitable for the all-solid-state battery. Patent Document 1 does not take into consideration the change in the internal resistance value of the all-solid-state battery, and does not adjust the pressure that restrains the all-solid-state battery according to the internal resistance value.

The present invention has been made in consideration of the above-mentioned problems, and aims to make it possible to adjust the restraining pressure on an all-solid-state battery in accordance with 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.

The present invention adopts the following configuration as a means for solving the above problems.

The first aspect of the present invention is an all-solid-state battery control device that controls the restraining pressure of an all-solid-state battery having a solid electrolyte layer, and is configured to include 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 restraining pressure based on the internal resistance value.

The second aspect of the present invention is the first aspect, in which the pressure adjustment unit compares a pressure upper limit value, which is an upper limit value of the restraint pressure, with the restraint pressure calculated based on the internal resistance value, and when the restraint pressure calculated based on the internal resistance value exceeds the pressure upper limit value, the pressure adjustment unit limits the restraint pressure of the all-solid-state battery to the pressure upper limit value.

A third aspect of the present invention is the second aspect of the present invention, which is configured to include a temperature detector that detects the temperature of the solid-state battery, and the pressure adjustment unit changes the upper pressure limit value according to the detection value of the temperature detector.

A fourth aspect of the present invention is any one of the first to third aspects, further comprising an abnormality determination unit that determines the presence or absence of an abnormality in the all-solid-state battery, and the abnormality determination unit determines the internal resistance value after the binding pressure adjustment estimated from the binding pressure determined based on the internal resistance value as an estimated internal resistance value, determines the internal resistance value of the all-solid-state battery as a post-adjustment internal resistance value based on the detection value of the voltage detector and the detection value of the current detector after the binding 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 post-adjustment internal resistance value.

A fifth aspect of the present invention is a configuration in which, in the fourth aspect, a temperature detector is provided for detecting the temperature of the all-solid-state battery, and the abnormality determination unit sets a required abnormality detection processing threshold for performing the detection processing for the presence or absence of the abnormality according to the detection value of the temperature detector, and performs the detection processing for the presence or absence of the abnormality when the difference between the estimated internal resistance value and the adjusted internal resistance value becomes equal to or greater than the required abnormality detection processing threshold.

A sixth aspect of the present invention is any one of the first to fifth aspects, further comprising a temperature detector for detecting the temperature of the all-solid-state battery, and the pressure adjustment unit reduces the restraining pressure on the all-solid-state battery below the restraining pressure based on the internal resistance value when the detected value of the temperature detector is equal to or lower than the necessary heating temperature of the all-solid-state battery.

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. In addition, 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 restraining 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 restraining pressure on the all-solid-state battery according to the internal resistance value of the all-solid-state battery.

1 is a block diagram showing a schematic configuration of an all-solid-state battery control device according to a first embodiment of the present invention. FIG. 4 is a flowchart for explaining the operation of the all-solid-state battery control device in the first embodiment of the present invention. FIG. 11 is a block diagram showing a schematic configuration of an all-solid-state battery control device according to a second embodiment of the present invention. 10 is a flowchart for explaining the operation of an all-solid-state battery control device in a second embodiment of the present invention. 13 is a flowchart for explaining the operation of an all-solid-state battery control device in a third embodiment of the present invention. 13 is a flowchart for explaining the operation of an all-solid-state battery control device in a fourth embodiment of the present invention.

Below, one embodiment of the solid-state battery control device according to the present invention will be described with reference to the drawings.

First Embodiment
1 is a block diagram showing a schematic configuration of an all-solid-state battery control device 1 according to the present embodiment. The all-solid-state battery control device 1 according to the present embodiment monitors an all-solid-state battery 10 and adjusts a restraining pressure acting on the all-solid-state battery 10.

First, an all-solid-state battery 10 in which the restraining pressure is adjusted by the all-solid-state battery control device 1 of this embodiment will be described. The all-solid-state battery 10 is a secondary battery that includes 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, which will be described later). 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 pressure mechanism 14, and a battery case 15.

Each cell 11 has a negative electrode composite layer 11a, a positive electrode composite layer 11b, and a solid electrolyte layer 11c. The negative electrode composite layer 11a, the positive electrode composite layer 11b, and the solid electrolyte layer 11c are arranged in a stacked manner.

The installation position of the all-solid-state battery 10 is not particularly limited, but in the following description, for convenience, the stacking direction of the negative electrode composite layer 11a, the positive electrode composite layer 11b, and the solid electrolyte layer 11c is the up-down direction. In the all-solid-state battery 10 shown in FIG. 1, the negative electrode composite layer 11a, the positive electrode composite layer 11b, and the solid electrolyte layer 11c are stacked in this order from the bottom up: the negative electrode composite layer 11a, the solid electrolyte layer 11c, and the positive electrode composite layer 11b.

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

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

The positive electrode composite layer 11b is disposed opposite the negative electrode composite layer 11a via the solid electrolyte layer 11c. The positive electrode composite layer 11b is a layer formed by mixing, for example, a granular positive electrode active material with, for example, a powdered solid electrolyte. For example, the positive electrode composite layer 11b is formed by pressure molding a mixture of the positive electrode active material and the solid electrolyte.

The positive electrode active material is not particularly limited, but may be, for example, _LiCoO2 , _LiNiO2 , _LiMn2O4 , _{or LiCo0.5} . The solid electrolyte contained in the positive electrode composite layer 11b is not particularly limited, but may be, for example, a sulfide-based electrolyte or an oxide-based electrolyte. The positive electrode composite layer 11b may contain a conductive auxiliary material or a binder.

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

As shown in FIG. 1, the all-solid-state battery 10 includes a plurality of cells 11 stacked vertically. These cells 11 are electrically connected in series. A negative electrode current collector 12 is connected to the negative electrode composite layer 11a of the cell 11 that is located at the bottom of the plurality of cells 11. A positive electrode current collector 13 is connected to the positive electrode composite layer 11b of the cell 11 that is located at the top of the plurality of cells 11.

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 part of the negative electrode current collector 12 drawn out to the outside of the battery case 15 becomes 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.

One end of the positive electrode 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 part of the positive electrode collector 13 drawn out to the outside of the battery case 15 becomes the positive electrode terminal of the all-solid-state battery 10. The material for forming the positive electrode collector 13 is not particularly limited, but aluminum, for example, can be used.

The pressure mechanism 14 is disposed on top of the stacked cells 11 and generates pressure to be applied to these cells 11. The pressure applied to the cells 11 from the pressure mechanism 14 is called the restraining pressure.

As shown in FIG. 1, the pressure mechanism 14 includes a pressure plate 14a and a pressure piston 14b. The pressure plate 14a is a plate member that is in contact from above with the upper surface of the uppermost cell among the multiple cells 11. The pressure plate 14a is formed, for example, to a size that covers the entire cell 11 when viewed from above.

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

This pressing force generates a confinement pressure that accelerates the cell 11. The pressurizing piston 14b is connected to the control unit 5, which will be described later, and adjusts the pressing force under the control of the control unit 5. In other words, the pressing force of the pressurizing piston 14b is adjusted under the control of the control unit 5, thereby adjusting the confinement pressure acting on the cell 11.

The battery case 15 is a container that houses multiple cells 11. The battery case 15 also houses a pressurizing mechanism 14. The battery case 15 is penetrated by the negative electrode collector 12 and the positive electrode collector 13 in a sealed state.

Such an 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. The all-solid-state battery 10 also stores regenerative power supplied from the load via the power conversion device and power supplied from an external power source via the power conversion device.

As shown in FIG. 1, the all-solid-state battery control device 1 of this 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 terminal (negative electrode collector 12) and the positive terminal (positive electrode collector 13) of the all-solid-state battery 10 via wiring. This voltage detector 2 detects the potential difference between the negative electrode terminal and the positive electrode terminal, and outputs the detected value.

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 terminal and the positive terminal when the AC signal is applied to the all-solid-state battery 10. The voltage detector 2 can also detect the battery voltage of the all-solid-state battery 10 when no AC signal is applied.

The current detector 3 is connected to the negative terminal of the all-solid-state battery 10 via a wire. This current detector 3 detects the value of the current flowing through the negative terminal of the all-solid-state battery 10 and outputs the detected value. In other words, the current detector 3 detects the current value of the negative terminal when an AC signal is applied to the all-solid-state battery 10. The current detector 3 may be connected to the positive terminal of the all-solid-state battery 10 via a wire. The current detector 3 can also detect the output current of the all-solid-state battery 10 when no AC signal is applied.

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

When the all-solid-state battery 10 is connected to a power converter, 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.

In addition, in this embodiment, the cell series resistance value is calculated using the so-called AC method. However, it is also possible to calculate the cell series resistance value using the so-called DC method. In this way, when the cell series resistance value is calculated 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.

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

The control unit 5 is formed by a computer device equipped with a storage device and an arithmetic unit. The storage device is made up of memories such as ROM (Read Only Memory) and RAM (Random Access Memory), and storage such as HDD (Hard Disk Drive) and SSD (Solid State Drive). The arithmetic unit performs calculations based on programs, operation signals, etc. This arithmetic unit is made up of an interface circuit and a CPU (Central Processing Unit), etc.

In this embodiment, the control unit 5 has functional units that are realized by the cooperation of hardware such as the above-mentioned storage device and arithmetic device, and programs and data stored in the storage device. As shown in FIG. 1, in this embodiment, the control unit 5 has, 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.

The cell series resistance calculation unit 5a calculates the cell series resistance value (internal resistance value) of the 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).

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. The cell series resistance calculation unit 5a also calculates the cell series resistance value based on the detected voltage value and detected current value obtained in a state in which the AC signal is supplied to the all-solid-state battery 10.

For example, more specifically, the cell series resistance calculation unit 5a calculates the cell series resistance value by dividing the change in the detected voltage value over a predetermined time by the change in the detected current value over a predetermined time.

The pressure adjustment unit 5b adjusts the confinement 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 confinement pressure to achieve a target cell series resistance value (hereinafter referred to as the target cell series resistance value) based on a relationship table or the like that shows the change in the cell series resistance value relative to the change in the confinement pressure. The pressure adjustment unit 5b adjusts the confinement pressure by controlling the pressurizing mechanism 14 so that the confinement pressure of the all-solid-state battery 10 becomes the calculated confinement pressure.

In this embodiment, the pressure adjustment unit 5b compares the confinement pressure calculated based on the target cell series resistance value with a pressure upper limit value, which is the upper limit value of the confinement pressure. Here, when the confinement pressure calculated based on the target cell series resistance value exceeds the pressure upper limit value, the pressure adjustment unit 5b limits the confinement pressure of the all-solid-state battery 10 to the pressure upper limit value.

The abnormality determination unit 5c determines the cell series resistance value after adjusting the restraint pressure estimated from the restraint pressure determined based on the target cell series resistance value as the estimated cell series resistance value (estimated internal resistance value). Note that when the restraint pressure determined based on the target cell series resistance value is a restraint pressure determined 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, provided that the restraint pressure determined based on the target cell series resistance value is within a range that does not exceed the pressure upper limit value.

The abnormality determination unit 5c also determines the cell series resistance value of the all-solid-state battery 10 as the adjusted cell series resistance value (adjusted internal resistance value) based on the detected voltage value and the detected current value after adjusting the restraint pressure. 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.

For example, if the cells 11 etc. are normal and no abnormality occurs in the all-solid-state battery 10, the adjusted cell series resistance value will be close to the estimated cell series resistance value even if there is an error. On the other hand, if the difference between the estimated cell series resistance value and the adjusted cell series resistance value is large, it is possible that an abnormality has occurred in one or more of the cells 11. For this reason, if 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 to detect an abnormality in the all-solid-state battery 10.

In this embodiment, the abnormality determination unit 5c compares the abnormality detection threshold value, which determines the need to execute an abnormality detection process to detect 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 abnormality detection threshold value.

The memory unit 5d stores programs and various data. For example, the memory unit 5d stores a relationship table showing the change in cell series resistance value in response to the change in restraining pressure, a target cell series resistance value, a pressure upper limit value, anomaly detection processing threshold value, etc.

Next, the operation of the solid-state battery control device 1 of this embodiment will be described with reference to the flowchart in FIG. 2. In the following description, the main operation is performed by the control unit 5.

As shown in FIG. 2, first, the cell series resistance value is calculated (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.

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.

In this embodiment, the cell series resistance calculation unit 5a calculates the cell series resistance by dividing the change in the detected voltage value over a given time by the change in the detected current value over a given time.

Next, as shown in FIG. 2, the restraint pressure is calculated (step S2). Here, the restraint pressure is calculated by the pressure adjustment unit 5b of the control unit 5. The pressure adjustment unit 5b calculates the restraint pressure to achieve the target cell series resistance value stored in the memory unit 5d based on the relationship table (a table showing the change in cell series resistance value relative to the change in restraint pressure) stored in the memory unit 5d and the cell series resistance value calculated in step S1.

Next, as shown in FIG. 2, a determination is made as to whether the restraint pressure calculated in step S2 exceeds the upper pressure limit (step S3). Here, the pressure adjustment unit 5b determines whether the calculated restraint pressure exceeds the upper pressure limit.

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

If it is determined in step S3 that the calculated restraint pressure exceeds the upper pressure limit, the pressure adjustment unit 5b limits the restraint pressure to the upper pressure limit (step S4). On the other hand, if it is determined in step S3 that the calculated restraint pressure does not exceed the upper pressure limit, the pressure adjustment unit 5b adjusts the restraint pressure (step S5).

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

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

Note that step S6 may be performed before step S5. That is, if it is determined that the restraint pressure calculated in step S3 exceeds the upper pressure limit, step S6 may be performed between steps S4 and S5. Also, if it is determined that the restraint pressure calculated in step S3 does not exceed the upper pressure limit, step S6 may be performed between steps S3 and S5.

Then, the adjusted cell series resistance value is calculated (step S7). Here, for example, the adjusted cell series resistance value is calculated by the cell series resistance calculation unit 5a of the control unit 5. The adjusted cell series resistance value is the cell series resistance that is found based on the detected voltage value and the detected current value after the adjustment of the restraint pressure is performed in step S5.

Here, the cell series resistance calculation unit 5a also causes the AC generator 4 to output an AC signal, as in step S1. The cell series resistance calculation unit 5a calculates the adjusted cell series resistance value by dividing the change in the detected voltage value over a predetermined time by the change in the detected current value over a predetermined time.

Next, it is determined whether the difference between the estimated cell series resistance value and the adjusted cell series resistance value is equal to or greater than the anomaly detection processing threshold (step S8). Here, for example, the anomaly determination unit 5c determines whether the difference between the estimated cell series resistance value and the adjusted cell series resistance value is equal to or greater than the anomaly detection processing threshold.

The abnormality determination unit 5c compares the abnormality detection processing threshold value, which determines the need to execute an abnormality detection processing to detect 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. As a result, the abnormality determination unit 5c executes step S8.

If the difference between the estimated cell series resistance value and the adjusted cell series resistance value is equal to or greater than the abnormality detection processing threshold, an abnormality detection processing is executed to detect an abnormality in the all-solid-state battery 10 (step S9). Here, for example, the abnormality determination unit 5c executes the abnormality detection processing to detect an abnormality in the all-solid-state battery 10.

When the anomaly detection process is executed, the presence or absence of an anomaly is notified to the operator, etc. For example, if no anomaly is found as a result of executing the anomaly detection process, the process may return to step S1. Also, even if no anomaly is found as a result of executing the normal detection process, it is possible to transition to step S1 unless instructed by the operator.

If it is determined in step S8 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 anomaly detection processing threshold, the process returns to step S1, for example. Here, a signal indicating that there is no anomaly is input from the anomaly determination unit 5c to the cell series resistance calculation unit 5a, and the cell series resistance calculation unit 5a executes step S1 again.

The all-solid-state battery control device 1 of this embodiment as described above controls the restraint pressure of the all-solid-state battery 10 having the solid electrolyte layer 11c. The all-solid-state battery control device 1 of this embodiment also 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. The pressure adjustment unit 5b also adjusts the restraint pressure based on the cell series resistance value.

As described above, the all-solid-state battery control device 1 of this 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. In addition, in the all-solid-state battery control device 1 of this 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 restraining pressure is adjusted based on the cell series resistance value. Therefore, according to the all-solid-state battery control device 1 of this embodiment, it is possible to adjust the restraining pressure on the all-solid-state battery 10 according to the cell series resistance value of the all-solid-state battery 10.

In the all-solid-state battery control device 1 of this embodiment, the pressure adjustment unit 5b compares the upper pressure limit value, which is the upper limit value of the restraint pressure, with the restraint pressure calculated based on the cell series resistance value. In addition, when the restraint pressure calculated based on the cell series resistance value exceeds the upper pressure limit value, the pressure adjustment unit 5b limits the restraint pressure of the all-solid-state battery 10 to the upper pressure limit value. According to the all-solid-state battery control device 1 of this embodiment, it is possible to prevent the restraint pressure exceeding the upper pressure limit value from acting on the cell 11.

The all-solid-state battery control device 1 of this embodiment also includes an abnormality determination unit 5c that determines whether or not there is an abnormality in the all-solid-state battery 10. The abnormality determination unit 5c determines the cell series resistance value after the confinement pressure adjustment estimated from the confinement pressure determined based on the cell series resistance value as the estimated cell series resistance value. The abnormality determination unit 5c also determines the cell series resistance value of the all-solid-state battery 10 as the adjusted cell series resistance value based on the detection value of the voltage detector 2 and the detection value of the current detector 3 after the confinement pressure adjustment. Furthermore, the abnormality determination unit 5c determines whether or not there is 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.

When the difference between the estimated cell series resistance value and the adjusted cell series resistance value is large, it is possible that an abnormality has occurred in one or more of the cells 11. According to the all-solid-state battery control device 1 of this embodiment, when the difference between the estimated cell series resistance value and the adjusted cell series resistance value is large, an abnormality detection process is executed to detect an abnormality in the all-solid-state battery 10. This makes it possible to quickly grasp the abnormality in the cell 11.

Second Embodiment
Next, a second embodiment of the present invention will be described. In the description of this embodiment, the description of the same parts as those of the first embodiment will be omitted or simplified.

Figure 3 is a block diagram showing a schematic configuration of the all-solid-state battery control device 1A of this embodiment. As shown in Figure 3, the all-solid-state battery control device 1A of this embodiment further includes a temperature detector 6 in addition to the all-solid-state battery control device 1 of the first embodiment.

The temperature detector 6 detects the temperature of the 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 solid-state battery 10.

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. In addition, 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.

The appropriate target cell series resistance value also changes due to the expansion and contraction of the solid electrolyte layer 11c, etc. For example, it is preferable to reduce the target cell series resistance value as the temperature of the all-solid-state battery 10 increases.

For this reason, in the all-solid-state battery control device 1A of this embodiment, a table showing the relationship between the temperature of the all-solid-state battery 10 and a previously determined target cell series resistance value (hereinafter referred to as the temperature-target cell series resistance relationship table) is stored in the memory unit 5d.

The upper pressure limit also changes due to expansion and contraction of the solid electrolyte layer 11c and the like caused by the temperature of the all-solid-state battery 10. For this reason, in the all-solid-state battery control device 1A of this embodiment, a table showing the relationship between the temperature of the all-solid-state battery 10 and the upper pressure limit (hereinafter referred to as the temperature-upper pressure limit relationship table) is stored in the memory unit 5d.

For example, 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 a temperature-target cell series resistance relationship table. The pressure adjustment unit 5b calculates the confinement pressure based on this target cell series resistance value. The pressure adjustment unit 5b also adjusts the confinement pressure by controlling the pressurizing mechanism 14 so that the confinement pressure of the all-solid-state battery 10 becomes the calculated confinement pressure.

The pressure adjustment unit 5b also sets the upper pressure limit from the detected temperature value input from the temperature detector 6 based on the temperature-upper pressure limit relationship table. The pressure adjustment unit 5b also compares the confinement pressure calculated based on the target cell series resistance value with the upper pressure limit, which is the upper limit of the confinement pressure. Here, if the confinement pressure calculated based on the cell series resistance value exceeds the upper pressure limit, the pressure adjustment unit 5b limits the confinement pressure of the all-solid-state battery 10 to the upper pressure limit.

Figure 4 is a flowchart for explaining the operation of the solid-state battery control device 1A of this embodiment.

As shown in FIG. 4, in the all-solid-state battery control device 1A of this embodiment, the temperature of the all-solid-state battery 10 is acquired (step S10) before step S1 of the first embodiment. 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.

Next, when calculating the restraint pressure in step S2, 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.

Furthermore, the pressure adjustment unit 5b uses the set target cell series resistance value to calculate the restraint pressure to achieve the target cell series resistance value stored in the memory unit 5d based on the relationship table (a table showing the change in cell series resistance value relative to the change in restraint pressure) stored in the memory unit 5d and the cell series resistance value calculated in step S1.

As shown in FIG. 4, in the all-solid-state battery control device 1A of this embodiment, the pressure upper limit is set (step S11) before step S3 of the first embodiment. Here, the pressure adjustment unit 5b determines the pressure upper limit from the detected temperature value based on the temperature-pressure upper limit relationship table stored in the memory unit 5d.

Then, the pressure adjustment unit 5b performs step S3. Here, the pressure adjustment unit 5b uses the pressure upper limit value set in step S11 to determine whether the restraint pressure calculated in step S2 exceeds the pressure upper limit value.

The all-solid-state battery control device 1A of this embodiment as described above is equipped with a temperature detector 6 that detects the temperature of the all-solid-state battery 10. In addition, the pressure adjustment unit 5b sets the target cell series resistance value (confining pressure) based on the temperature of the all-solid-state battery 10. This makes it possible to set a target cell series resistance value (confining pressure) appropriate for the temperature of the all-solid-state battery 10.

The solid-state battery control device 1A of this embodiment is also equipped with a temperature detector 6 that detects the temperature of the solid-state battery 10. The pressure adjustment unit 5b changes the upper pressure limit according to the detection value of the temperature detector 6. This makes it possible to set an appropriate upper pressure limit according to the temperature of the solid-state battery 10.

Third Embodiment
Next, a third embodiment of the present invention will be described. In the description of this embodiment, the description of the same parts as those of the first or second embodiment will be omitted or simplified.

The solid-state battery control device of this embodiment is equipped with a temperature detector 6, as in the second embodiment. In the solid-state battery 10, when the temperature of the solid-state battery 10 is relatively high, the solid electrolyte layer 11c and the like expand.

In addition, 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 abnormality detection processing threshold in accordance with such expansion and contraction of the solid electrolyte layer 11c and the like.

For this reason, in the all-solid-state battery control device of this embodiment, a table showing the relationship between the temperature of the all-solid-state battery 10 and the abnormality detection processing threshold (hereinafter referred to as the temperature-abnormality detection processing threshold relationship table) is stored in the memory unit 5d.

The abnormality determination unit 5c sets the required abnormality detection processing threshold from the detected temperature value input from the temperature detector 6 based on the temperature-required abnormality detection processing relationship table. The abnormality determination unit 5c executes the abnormality 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 required abnormality detection processing threshold.

Figure 5 is a flow chart 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 seen by comparing it with the operation of the all-solid-state battery control device 1A of the second embodiment shown in Figure 4, the abnormality detection processing threshold is set before step S8 (step S20).

Here, the abnormality determination unit 5c sets the abnormality detection threshold. The abnormality determination unit 5c determines the upper pressure limit from the abnormality detection threshold based on the temperature-abnormality detection threshold relationship table stored in the memory unit 5d.

Then, the abnormality determination unit 5c determines whether the difference between the estimated cell series resistance value and the adjusted cell series resistance value is equal to or greater than the abnormality detection processing threshold value set in step S20 (step S8).

The solid-state battery control device of this embodiment as described above is equipped with a temperature detector 6 that detects the temperature of the solid-state battery 10. In addition, the abnormality determination unit 5c sets an abnormality detection processing threshold based on the temperature of the solid-state battery 10.

In addition, when the difference between the estimated cell series resistance value and the adjusted cell series resistance value becomes equal to or greater than the abnormality detection threshold, the abnormality determination unit 5c performs a process to detect the presence or absence of an abnormality. This makes it possible to set an appropriate abnormality detection threshold according to the temperature of the all-solid-state battery 10.

Fourth Embodiment
Next, a fourth embodiment of the present invention will be described. In the description of this embodiment, the description of the same parts as those of the first or second embodiment will be omitted or simplified.

When the temperature of the all-solid-state battery 10 drops, the output may not be stable. For this reason, it is preferable to heat 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 detection value of the temperature detector is stored in the memory unit 5d as the required temperature to which the all-solid-state battery 10 needs to be heated.

The pressure adjustment unit 5b compares the detected temperature value with the required temperature to be increased. As a result, if the detected temperature value is equal to or lower than the required temperature to be increased, the pressure adjustment unit 5b reduces the restraint pressure applied to the solid-state battery 10 below the restraint pressure based on the target cell series resistance value.

By reducing the confinement pressure in this manner, 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 has decreased, it is possible to actively heat the all-solid-state battery 10 by reducing the confinement pressure.

Figure 6 is a flow chart 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 seen by comparing with the operation of the all-solid-state battery control device 1A of the second embodiment shown in Figure 4, before step S2, it is determined whether the detected temperature value is equal to or higher than the required temperature for heating (step S30).

If the pressure adjustment unit 5b determines in step S30 that the detected temperature value is not equal to or higher than the required temperature for heating, the process proceeds to step S3. On the other hand, if the pressure adjustment unit 5b determines in step S30 that the detected temperature value is equal to or higher than the required temperature for heating, the restraint pressure is adjusted to be smaller than the restraint pressure corresponding to the target cell series resistance value (step S31). Then, the process returns to step S1.

The solid-state battery control device of this embodiment as described above is equipped with a temperature detector 6 that detects the temperature of the solid-state battery 10. In addition, the abnormality determination unit 5c sets an abnormality detection processing threshold based on the temperature of the solid-state battery 10.

In addition, when the detection value of the temperature detector is equal to or lower than the required temperature for heating the all-solid-state battery 10, the pressure adjustment unit 5b reduces the restraint pressure on the all-solid-state battery 10 to less than the restraint pressure based on the cell series resistance value. This makes it possible to heat the all-solid-state battery 10 as needed.

The above describes a preferred embodiment of the present invention with reference to the attached drawings, but it goes without saying that the present invention is not limited to the above embodiment. The shapes and combinations of the components shown in the above embodiment are merely examples, and various modifications can be made based on design requirements, etc., without departing from the spirit of the present invention.

For example, in the above embodiment, a configuration has been described in which the control unit 5 has an abnormality determination unit 5c as a functional unit. 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 have an abnormality determination unit 5c as a functional unit. In other words, it is also possible to adopt a configuration in which the control unit 5 does not perform abnormality determination processing. In such a case, for example, the configuration is such that steps S6, S7, S8, and S9 shown in the flowchart of FIG. 1 etc. are not performed.

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...Pressure mechanism, 14a...Pressure plate, 14b...Pressure piston, 15...Battery case

Claims (4)

An all-solid-state battery control device for controlling a confinement 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 adjusting unit that adjusts the restraining pressure based on the internal resistance value ;
a temperature detector for detecting a temperature of the all-solid-state battery;
Equipped with
The pressure adjustment unit is
A pressure upper limit value that is an upper limit value of the confining pressure is compared with the confining pressure calculated based on the internal resistance value,
When the confining pressure calculated based on the internal resistance value exceeds the pressure upper limit value, the confining pressure of the all-solid-state battery is limited to the pressure upper limit value;
The pressure upper limit is changed in response to a detection value of the temperature detector.
An all-solid-state battery control device comprising: An all-solid-state battery control device for controlling a confinement 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 adjusting unit that adjusts the restraining pressure based on the internal resistance value ;
an abnormality determination unit that determines whether or not there is an abnormality in the all-solid-state battery;
Equipped with
The abnormality determination unit is
The internal resistance value after the confining pressure adjustment estimated from the confining pressure calculated based on the internal resistance value is calculated as an estimated internal resistance value;
After adjusting the restraining pressure, an internal resistance value of the all-solid-state battery is calculated as a post-adjustment internal resistance value based on the detection value of the voltage detector and the detection value of the current detector;
The presence or absence of an abnormality in the all-solid-state battery is determined based on a difference between the estimated internal resistance value and the adjusted internal resistance value.
An all-solid-state battery control device comprising: A temperature detector is provided for detecting a temperature of the all-solid-state battery,
The abnormality determination unit is
setting a threshold value for detecting an abnormality to be detected, the abnormality detection process being performed according to the detected value of the temperature detector;
3. The all-solid-state battery control device according to claim 2 , wherein the abnormality detection process is performed when a difference between the estimated internal resistance value and the adjusted internal resistance value becomes equal to or greater than the abnormality detection process threshold value. An all-solid-state battery control device for controlling a confinement 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 adjusting unit that adjusts the restraining pressure based on the internal resistance value ;
a temperature detector for detecting a temperature of the all-solid-state battery;
Equipped with
The pressure adjustment unit reduces a restraining pressure applied to the all-solid-state battery to a level lower than the restraining pressure based on the internal resistance value when a detection value of the temperature detector is equal to or lower than a necessary temperature that requires heating of the all-solid-state battery.
An all-solid-state battery control device comprising: