Battery system

Abstract

To provide a battery system.SOLUTION: A battery system 1 includes: a battery cell 21; a pressure application mechanism 15 for applying a restraining pressure to the battery cell 21; and a controller 10 for controlling the pressure application mechanism 15 so that the restraining pressure becomes a target restraining pressure. The controller 10 measures the internal resistance measurement value of the battery cell 21, estimates the internal resistance measurement value of the battery cell 21 on the basis of the target restraining pressure, and determines a defect in the restraining pressure on the basis of the difference between the internal resistance measurement value when the restraining pressure is the target restraining pressure and the internal resistance estimation value.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a battery system capable of correcting a confinement pressure of an all-solid-state battery applied by a pressurizing unit. [Background technology]

[0002] A charging system for an all-solid-state battery mounted on a vehicle is known (Patent Document 1). This charging system for an all-solid-state battery includes a pressurizing unit that applies a confining pressure to the all-solid-state battery, and a pressure control unit that controls the confining pressure. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2015-95281 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the above charging system, the confining pressure applied to the solid-state battery is controlled to be a target surface pressure (target confining pressure) according to the scene. However, the confining pressure applied to the solid-state battery may deviate from the target confining pressure due to aging of the solid-state battery, the pressurizing unit, etc. However, in the conventional charging system, there is a problem that it is not possible to grasp the deviation of the actual confining pressure from the target confining pressure.

[0005] The problem to be solved by the present invention is to provide a battery system capable of grasping the deviation of the bundling pressure from a target bundling pressure. [Means for solving the problem]

[0006] The present invention solves the above problem by providing a determination unit that determines whether the confining pressure is defective based on the difference between the measured internal resistance value and the estimated internal resistance value at the target confining pressure. Effect of the Invention

[0007] According to the present invention, it is possible to determine the deviation of the confining pressure from the target value. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a block diagram showing a battery system according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a flowchart showing a method for inspecting a confining pressure using a battery system according to an embodiment of the present invention. [Diagram 3] FIG. 3 is a graph showing the relationship between the direct current resistance (DCR) of a battery cell and the restraining pressure applied to the battery cell. [Figure 4] FIG. 4 is a graph showing an example of the relationship between the motor angle and the target surface pressure according to the SOC. [Diagram 5] FIG. 5 is a graph showing an example of the relationship between the DC resistance and the binding pressure applied to the battery cell according to the temperature of the battery cell. [Figure 6] FIG. 6 is a graph showing an example of the relationship between the DC resistance estimated value correction coefficient and the SOC. [Figure 7] FIG. 7 is a graph showing an example of the relationship between the DC resistance estimated value correction coefficient and the SOH. [Figure 8] FIG. 8 is a graph illustrating an example of the difference between the estimated DC resistance value and the measured DC resistance value. [Figure 9] FIG. 9 is a graph illustrating an example of correction of a table of target surface pressure and motor position according to the SOC. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Fig. 1 is a block diagram showing a battery system 1 of the present embodiment. Although not particularly limited, the battery system 1 in the present embodiment is mounted on, for example, a vehicle.

[0010] As shown in FIG. 1, the battery system 1 includes a controller 10, a voltage sensor 11, a current sensor 12, a temperature sensor 13, a load removal device 14, and a pressure application mechanism 15.

[0011] The controller 10 in this embodiment corresponds to an example of the "pressure control unit", "measurement unit", "estimation unit", "determination unit", "SOC measurement unit", "SOH measurement unit" and "charge / discharge history recording unit" in the present invention. The voltage sensor 11 in this embodiment corresponds to an example of the "voltage measurement unit" in the present invention. The current sensor 12 in this embodiment corresponds to an example of the "current measurement unit" in the present invention. The temperature sensor 13 in this embodiment corresponds to an example of the "temperature measurement unit" in the present invention. The load extraction device 14 in this embodiment corresponds to an example of the "current extraction unit" in the present invention. The pressure application mechanism 15 in this embodiment corresponds to an example of the "pressurization unit" in the present invention.

[0012] The controller 10 is a battery control unit (BCU). The controller 10 is composed of a memory such as a ROM or a RAM, and a processor such as a CPU. The controller 10 manages the state of the battery module 2 based on a detected voltage detected by a voltage sensor 11, a detected current detected by a current sensor 12, a detected temperature detected by a temperature sensor 13, and the like, and determines the SOC usage range of the battery module 2 according to the state of the battery module 2.

[0013] The controller 10 also controls the load take-off device 14. By controlling the load take-off device 14, the controller 10 can make a desired amount of current flow from the battery cells 21 of the battery module 2 to the load take-off device 14.

[0014] The load take-off device 14 is a device that takes out current from the multiple battery cells 21 that make up the battery module 2 in response to a command from the control controller 10. Although not particularly limited, the load take-off device 14 is, for example, a DC-DC converter that charges a low-power battery that supplies power to the control controller 10. However, the load take-off device 14 is not limited to this as long as it can take out any power at an appropriate timing.

[0015] Moreover, the controller 10 controls the pressure application mechanism 15. The controller 10 controls the pressure application mechanism 15 to adjust the value of the pressure (binding pressure) applied to the battery module 2 to a target binding pressure.

[0016] Furthermore, as will be described in detail later, the controller 10 judges whether the binding pressure applied by the pressure application mechanism 15 is defective. That is, it judges whether the actual binding pressure deviates from the target binding pressure by a certain amount or more.

[0017] The voltage sensor 11 is a sensor for detecting the voltage between the terminals of the battery module 2. The voltage sensor 11 is connected between wiring connected to the positive and negative electrodes of the battery module 2. This wiring is connected to a load take-off device 14. The current sensor 12 is a sensor for detecting the input / output current of the battery module 2. The current sensor 12 is connected to wiring connected to the positive or negative electrode of the battery module 2. The temperature sensor 13 is provided in the battery module 2. The temperature sensor 13 is a sensor for detecting the temperature of the battery module 2.

[0018] The pressure application mechanism 15 applies pressure to the battery module 2 by pressing the battery module 2 along the stacking direction of the battery cells 21 in the battery module 2. Although not particularly shown, the battery module 2 in this embodiment includes a plurality of battery cells 21, and the battery cells 21 have, for example, a flat plate shape. In this battery module 2, the plurality of battery cells 21 are stacked so that the main surfaces of the battery cells 21 are in contact with each other.

[0019] The pressure application mechanism 15 in this embodiment includes a driver 151 , a motor gear 152 , a pair of pressure plates 153 , and a plurality of shafts 154 .

[0020] The driver 151 operates a motor included in the motor gear 152. The driver 151 controls the driving of the motor based on a control signal from the controller 10.

[0021] The motor-gear 152 has a motor and a gear. This motor rotates and drives the gear in response to the output from the driver 151. The gear converts the drive from the motor into drive of the pressure plate 153 in the stacking direction.

[0022] The pressure plate 153 moves up and down by a driving force transmitted via a gear. In this embodiment, the upper pressure plate 153 is a plate member that can move along the stacking direction, and the lower pressure plate 153 is a plate member that does not move along the stacking direction. In this embodiment, the pressure applied to the battery module 2 can be controlled to increase by moving the upper pressure plate 153 downward in the figure, and the pressure applied to the battery module 2 can be controlled to decrease by moving the upper pressure plate 153 upward in the figure.

[0023] Specifically, the lower pressure plate 153 is fixed to the shaft 154 and supports the battery module 2. On the other hand, the upper pressure plate 153 is not fixed to the shaft 154, but is movable along the extension direction of the shaft 154, and applies pressure to the battery module 2 from above in response to the force transmitted from the motor gear 152. In addition, the upper pressure plate 153 can move along the stacking direction in response to the expansion and contraction of the battery module 2 accompanying charge and discharge, and the expansion and contraction of the battery module 2 accompanying changes in the pressure applied by the upper pressure plate 153 to the battery module 2.

[0024] The battery module 2 is electrically connected to a charging device (not shown). The charging device connected to the battery cells 21 is, for example, a device for charging the battery module 2 mounted on an electric vehicle or a hybrid vehicle. Charging the battery module 2 mounted on the vehicle is performed by removing the charging cable from the charging device, attaching a charging gun at the end of the charging cable to a connector of the vehicle's charging port, and operating a charging start switch. The controller 10 manages the state of charge (SOC) of the battery cells 21 included in the battery module 2, and controls each of the charging devices so that the state of charge of the battery module 2 becomes a target state of charge.

[0025] The battery module 2 is also electrically connected to a load (not shown) such as a motor. The load is a device that operates using the power of the battery module 2, such as a motor that serves as a drive source for the vehicle, and auxiliary devices such as an air conditioner and lights. The battery module 2 is discharged under the control of the controller 10 in response to a system request or an external power request. The system request corresponds to a command from an on-board computer such as an ECU while the vehicle is running. With regard to a power request from the outside, for example, when an air conditioner is operated by a timer setting in response to a command from an external device such as a mobile terminal before the vehicle starts running so that the interior of the vehicle is at an appropriate temperature when the vehicle starts running, the command from the external device corresponds to a power request from the outside.

[0026] The battery module 2 installed in an electric vehicle or a hybrid vehicle may be used for Vehicle Grid Integration (VGI). VGI is a technology in which an electric vehicle or a hybrid vehicle equipped with a battery module 2 is connected to a power grid, and the power stored in the battery module 2 is supplied to the power grid (load) via the power grid.

[0027] The battery cells 21 included in the battery module 2 are all-solid-state batteries having at least a positive electrode, a solid electrolyte, and a negative electrode. The positive electrode contains at least a positive electrode active material capable of absorbing and releasing an alkali metal such as lithium (Li), sodium (Na), or potassium (K), and preferably contains a positive electrode active material containing sulfur, although it is not particularly limited. As the solid electrolyte, for example, a sulfide solid electrolyte or an oxide solid electrolyte can be used, and it is preferable to use a sulfide solid electrolyte. The negative electrode may be one containing lithium, and preferably contains, for example, lithium metal.

[0028] Hereinafter, a method for inspecting the confining pressure of the battery module 2 using such a battery system 1 will be described. Fig. 2 is a flowchart showing the method for inspecting the confining pressure using the battery system 1 of this embodiment. The inspection method shown in Fig. 2 is repeatedly executed at predetermined intervals.

[0029] In this inspection method, first, in step S1, it is determined whether a predetermined time has passed since the end of charging and discharging the battery module 2. This predetermined time is the time from the end of charging and discharging the battery module 2 until relaxation ends or the influence of charging and discharging disappears (the time until the voltage that increased due to charging drops and settles down). This predetermined time can be obtained in advance by experiment or the like. The predetermined time can be measured by the control controller 10 using the extraction power command, charging power command, or current sensor 12 of the control controller 10. This makes it possible to inspect the deviation between the actual surface pressure and the target by matching conditions, even for a battery module 2 that has characteristics in which the internal resistance value changes greatly due to relaxation.

[0030] In addition, since the relaxation of the battery module 2 has been completed, the vehicle in which the battery module 2 is mounted is also stopped. By performing the inspection in this embodiment when the vehicle is stopped, as described below, it is possible to set a target pressure at which the internal resistance estimated value has a high sensitivity to the surface pressure, and then perform the inspection, thereby enabling a highly accurate inspection.

[0031] Although not limited thereto, in step S1, it is also determined whether or not the inspection method is complete. That is, the controller 10 determines whether or not step S15, which will be described later, is complete, and if not, step S2 is executed.

[0032] If the above-mentioned predetermined time has elapsed and the inspection method is not completed, then in step S2, the controller 10 changes the target surface pressure (target confining pressure) from the normal pressure to the inspection surface pressure. This makes it possible to set a target pressure with high sensitivity of the internal resistance estimate value to the surface pressure, and to perform an inspection with high accuracy.

[0033] 3 is a graph showing the relationship between the direct current resistance (DCR) of the battery cell 21 and the confinement pressure applied to the battery cell 21. E In order to make it easier to detect an increase in resistance due to insufficient surface pressure, R1 A lower inspection range P R2 Set the pressure within the normal range P R1 is the pressure range required to operate the vehicle's control system. E The specific value of may be determined based on the rate at which deterioration of the battery cells 21 and the pressure application mechanism 15 progresses, the frequency at which inspections can be performed, and the like.

[0034] More specifically, the target surface pressure for inspection P E is greater than the seismic demand pressure P0 and the lower limit confining pressure P m The earthquake resistance required pressure P0 can be made smaller than the required earthquake resistance pressure P0. Here, the earthquake resistance required pressure P0 is the minimum pressure required to maintain contact between the pressure plates 153 and the battery modules 2. In this embodiment, it is the minimum pressure at which the battery modules 2 do not fall out from between the pressure plates 153 even if an external force due to an impact, vibration, or the like is applied to the battery modules 2. By making the pressure larger than the earthquake resistance required pressure P0, it is possible to prevent the battery modules 2 from falling out.

[0035] On the other hand, the performance requirement pressure P mis the pressure at which the electrical resistance of the battery cell 21 becomes equal to the threshold value, and this threshold value is the maximum electrical resistance within the range of electrical resistance of the battery cell at which the battery cell can input and output the charge / discharge power required to operate the vehicle control system. m is greater than the seismic demand pressure P0.

[0036] 2, next, in step S3, the SOC is estimated. The SOC can be calculated from an integrated value of the discharge current of the battery module 2 or the current charged to the battery module 2. Alternatively, the SOC can be calculated by other common methods.

[0037] Next, in step S4, the estimated SOC value and the target surface pressure P for inspection are E Based on the SOC, the motor operation amount is determined, and motor drive is started. FIG. 4 is a graph showing an example of the relationship between the motor angle and the target surface pressure according to the SOC. As shown in FIG. 4, by acquiring the relationship between the motor angle and the target surface pressure in advance, the motor operation amount can be determined based on the relationship. Specifically, based on the SOC value, the cell length (height) can be calculated, and based on the motor angle, the distance between the pressure plates 153 can be calculated. Therefore, by experimentally acquiring the relationship between the SOC value, the motor angle, and the target surface pressure in advance, the required motor operation amount can be calculated. Note that, when an elastic body or other components are included as the pressure application mechanism, the above-mentioned relationship can be experimentally created in advance by taking into account the length of the elastic body relative to the target surface pressure.

[0038] As shown in FIG. 2, next, in step S5, a target surface pressure P E If the pressure plate 153 has moved to an appropriate position, in step S6, the controller 10 commands the load take-off device 14 to take out a predetermined amount of power A from the battery module 2. If it is determined in step S5 that the movement has not been completed, the inspection process is temporarily terminated and is restarted from this step in the next calculation cycle.

[0039] Next, in step S7, controller 10 determines whether or not the power extracted by load extractor 14 has reached power A. If it is determined that the extracted power has reached power A, then in step S8, the current value and voltage value are measured. The current value is measured by current sensor 12, and the voltage value is measured by voltage sensor 11. Note that, if it is determined in step S7 that the extracted power has not reached power A, the inspection process is temporarily terminated and resumed from this step in the next calculation cycle.

[0040] Next, in step S9, a direct current resistance (DCR) measurement value is calculated based on the measured current and voltage values. In this embodiment, the DCR is calculated from one current and one voltage, but the present invention is not limited to this. The direct current resistance may be calculated using the current and voltage values ​​after power B is extracted in addition to the current and voltage values ​​after power A is extracted. The direct current resistance measurement value in this embodiment corresponds to an example of the "internal resistance measurement value" in the present invention.

[0041] Next, in step S10, it is determined whether the difference between the DC resistance estimate value of the battery cell 21 and the DC resistance measurement value is equal to or greater than a predetermined value. By measuring the relationship between the DC resistance and the binding pressure in advance and storing it in the control controller 10, the DC resistance estimate value can be calculated based on the stored relationship and the target surface pressure. In this way, when the DC resistance estimate value is calculated and the difference between the DC resistance measurement value and the predetermined value or greater, it is determined that there is a deviation between the current binding pressure and the target binding pressure. That is, in this case, the control controller 10 determines that the current binding pressure is poor. The DC resistance estimate value in this embodiment corresponds to an example of the "internal resistance estimate value" in the present invention.

[0042] The predetermined value used for defect judgment may be determined taking into consideration the surface pressure difference (lower limit) resulting from measurement error of the estimated DC resistance value, the unacceptable cell charge / discharge performance (upper limit), and the surface pressure (upper limit) that will cause cell damage.

[0043] FIG. 5 is a graph showing an example of the relationship between the DC resistance and the binding pressure applied to the battery cell 21 depending on the temperature of the battery cell 21. As shown in FIG. 5, the relationship between the DC resistance and the binding pressure may change depending on the temperature of the battery cell 21. In particular, the change occurs in the inspection zone P R2 This may become noticeable within a certain temperature range. Therefore, the relationship between the DC resistance and the binding pressure for each temperature of the battery cell 21 may be stored in the controller 10, and an estimated internal resistance value may be calculated based on the temperature measurement value of the battery cell 21 measured by the temperature sensor 13, using the relationship between the DC resistance and the binding pressure corresponding to the temperature measurement value. This makes it possible to calculate an estimated DC resistance value with high accuracy even for a battery cell 21 that has characteristics in which the internal resistance value changes greatly with temperature.

[0044] The relationship between the DC resistance and the restraining pressure may change depending on the SOC and SOH of the battery cell 21. Therefore, the DC resistance estimated value may be corrected based on the SOC and SOH by multiplying the DC resistance estimated value calculated based on the target surface pressure by a DC resistance estimated value correction coefficient. This makes it possible to calculate a highly accurate DC resistance estimated value even for a battery cell 21 that has characteristics in which the internal resistance value changes greatly due to the SOC and SOH.

[0045] Fig. 6 is a graph showing an example of the relationship between the DC resistance estimated value correction coefficient and the SOC, and Fig. 7 is a graph showing an example of the relationship between the DC resistance estimated value correction coefficient and the SOH. In the example shown in Fig. 6 and Fig. 7, the value of the correction coefficient is made smaller as the SOC and SOH are larger. Note that the relationship between the correction coefficient and the SOC and SOH is not limited to the relationship shown in Fig. 6 and Fig. 7.

[0046] In addition, the relationship between the DC resistance and the restraining pressure may change depending on the charge and discharge history of the battery cell 21. Therefore, the controller 10 stores in advance the relationship between the DC resistance and the restraining pressure in the charged state of the battery cell 21 measured in an experiment, and records the charge and discharge history based on the measurement value of the current sensor 12. Then, based on the recorded charge and discharge history, it is determined whether the battery cell 21 is after charging or after discharging. If the battery cell 21 is after charging, the internal resistance estimate value may be calculated based on the relationship between the DC resistance and the restraining pressure in the charged state, and if the battery cell 21 is after discharging, the internal resistance estimate value may be calculated based on the relationship between the DC resistance and the restraining pressure in the discharged state. This makes it possible to calculate a highly accurate DC resistance estimate value even for a battery cell 21 that has a characteristic in which the hysteresis of the internal resistance value depending on the charge and discharge direction is large.

[0047] Figure 8 shows the estimated DC resistance R E and the measured DC resistance R M 8 is a graph illustrating the difference between the confining pressure and the target surface pressure P E If so, the DC resistance is the estimated DC resistance R E However, in the case of Figure 8, the measured DC resistance value R M is the estimated DC resistance R E The value deviated from (in this embodiment, R M >R E ) and the actual confining pressure is the DC resistance measurement value R M The corresponding confining pressure P M In other words, the estimated DC resistance R E and the measured DC resistance R M Based on the difference between E Actual confining pressure P from M In step S10, the difference ΔP between the estimated DC resistance R E and the measured DC resistance R M If the difference is less than the predetermined value, the process proceeds to step S12.

[0048] Such a difference ΔP occurs because the motor position (motor angle) for obtaining the target confining pressure has changed from the initial state due to aging deterioration of the battery cells 21 and aging deterioration of the pressure application mechanism 15. Therefore, if it is determined in step S10 of Fig. 2 that the difference between the estimated DC resistance value and the measured DC resistance value is equal to or greater than a predetermined value, the target surface pressure and motor position tables are corrected in step S11.

[0049] Fig. 9 is a graph for explaining an example of correction of the table of the target surface pressure and the motor position according to the SOC. In this embodiment, as shown in Fig. 8, the actual surface pressure is insufficient with respect to the target surface pressure, so as shown in Fig. 9, the straight line L1 showing the table of the actual target surface pressure and the motor position is corrected to a straight line L2 so that the target surface pressure becomes smaller. In other words, the table can be corrected so that the motor position coincides with the actual surface pressure corresponding to the motor position.

[0050] In order to avoid excessive correction, the correction value may be set as a preset fixed value, and the table may be repeatedly corrected as the inspection is repeated so that the motor position gradually coincides with the actual surface pressure corresponding to that motor position.

[0051] 2, in step S12, the controller 10 changes the target surface pressure from the inspection surface pressure to the normal pressure, and in step S13 starts driving the motor. Next, in step S14, it is determined whether the motor position has moved to the normal pressure. If it is determined that the movement has been completed, then in step S15, the inspection is completed. Note that, if it is determined that the movement has not been completed in step S14, the inspection process is temporarily terminated, and is resumed from this step in the next calculation cycle.

[0052] The battery system 1 as described above can determine the deviation of the confining pressure from the target value due to aging or the like of the battery cells 21 and the pressure application mechanism 15. Furthermore, by inspecting the confining pressure using DC resistance as the internal resistance as described above, the confining pressure can be inspected using sensors and actuators (load removal device 14, etc.) that are normally included in the battery system 1 with almost no additional cost.

[0053] After the inspection at a specific inspection target pressure is completed, the inspection target pressure may be gradually lowered and the above inspection may be performed multiple times. This makes it possible to obtain the relationship between the DC resistance and the surface pressure, even when the inspection is performed on battery cells 21 that have characteristics that make it difficult for the internal resistance to change even when the surface pressure is lowered to a certain extent, or when the rate at which deterioration progresses over time cannot be predicted and an appropriate inspection target pressure cannot be determined, making it easier to grasp the deviation in the surface pressure. In other words, when an accurate inspection cannot be performed with a single inspection target pressure, the deviation in the surface pressure can be grasped with high accuracy.

[0054] In the above embodiment, the inspection is performed when the vehicle is stopped, but this is not limiting. When the temperature of the battery cells 21 is low, the DC resistance is high, so that the above inspection can be performed even when the vehicle is operating as long as the temperature of the battery cells 21 is low.

[0055] Furthermore, in the above embodiment, the battery system 1 has been described as having a single battery module 2, but the battery system 1 may have a plurality of battery modules 2. In this case, the battery system 1 has a plurality of pressure application mechanisms 15 corresponding to the plurality of battery modules 2, and can perform the above-mentioned inspection by applying a target surface pressure for inspection to each individual battery module 2 and estimating the DC resistance of each battery module 2. This makes it possible to perform optimal correction according to aging deterioration that may differ for each module.

[0056] In the above embodiment, when it is determined in step S10 that the difference between the estimated DC resistance value and the measured DC resistance value is equal to or greater than a predetermined value, the target surface pressure and the motor position table are corrected, but this is not limited to the above. When it is determined that the difference between the estimated DC resistance value and the measured DC resistance value is equal to or greater than a predetermined value, the controller 10 may determine to prohibit charging and discharging of the battery cell 21. This makes it possible to prevent charging and discharging of the battery cell 21 when an abnormality occurs in which the surface pressure deviation is greater than expected. [Explanation of symbols]

[0057] 1...Battery system 1 10...Controller 11…Voltage sensor 12...Current sensor 12 13...Temperature sensor 14...Load removal device 15...Pressure application mechanism

Claims

1. All-solid-state batteries and A pressurizing unit that applies a confining pressure to the all-solid-state battery; A pressure control unit capable of controlling the pressurizing unit so that the confining pressure becomes a target confining pressure; A measurement unit that measures an internal resistance measurement value of the all-solid-state battery; An estimation unit that estimates an internal resistance estimate value of the all-solid-state battery based on the target confinement pressure; A battery system comprising: a determination unit that determines whether the confining pressure is defective based on a difference between the internal resistance measurement value and the internal resistance estimation value at the target confining pressure.

2. The battery system according to claim 1 , The battery system is mounted on a vehicle, The measurement unit is a battery system that measures an internal resistance of the all-solid-state battery when the vehicle is stopped.

3. The battery system according to claim 1 , The measurement unit measures the internal resistance of the all-solid-state battery after a predetermined time has elapsed since charging and discharging of the all-solid-state battery is stopped.

4. The battery system according to claim 1 , The target confining pressure is lower than the lower limit confining pressure, The lower limit confining pressure is lower than the performance required pressure, the performance required pressure is a pressure at which the electrical resistance of the all-solid-state battery has a threshold value; The threshold value is a maximum value of the electrical resistance within a range of electrical resistance of the all-solid-state battery that enables the all-solid-state battery to input and output charging / discharging power necessary to operate a vehicle control system.

5. The battery system according to claim 1 , The measurement unit measures the internal resistance of the all-solid-state battery at two or more different points of the target confinement pressure.

6. The battery system according to claim 1 , The battery system further includes a temperature measurement unit that measures a temperature of the all-solid-state battery, The estimation unit calculates the internal resistance estimated value based on a temperature measurement value measured by the temperature measurement unit.

7. The battery system according to claim 1 , The battery system further includes an SOC measurement unit that measures an SOC of the all-solid-state battery, The estimation unit calculates the internal resistance estimated value based on an SOC measurement value measured by the SOC measurement unit.

8. The battery system according to claim 1 , The battery system further includes a SOH measurement unit that measures the SOH of the all-solid-state battery, The estimation unit calculates the internal resistance estimated value based on a SOH measurement value measured by the SOH measurement unit.

9. The battery system according to claim 1 , The battery system includes: A current measuring unit that measures a current of the all-solid-state battery; A charge / discharge history recording unit that records a charge / discharge history of the all-solid-state battery, The estimation unit calculates the internal resistance estimated value based on the charge / discharge history recorded in the charge / discharge history recording unit.

10. The battery system according to claim 1 , The battery system includes: A current measuring unit that measures a current of the all-solid-state battery; A voltage measurement unit that measures a voltage of the all-solid-state battery; A current extraction unit that extracts a current from the all-solid-state battery, The estimation unit calculates the internal resistance estimated value based on a current measurement value of the current measurement unit and a voltage measurement value of the voltage measurement unit when the current is taken out by the current taking unit.

11. The battery system according to claim 1 , The all-solid-state battery includes a plurality of all-solid-state battery modules each including one or more stacked all-solid-state battery cells; the pressurizing unit is capable of applying the confining pressure to each of the all-solid-state battery modules, The determination unit determines whether the confining pressure is defective for each of the all-solid-state battery modules based on a difference between the measured internal resistance value and the estimated internal resistance value at the target confining pressure.

12. The battery system according to claim 1 , The pressure control unit corrects the confining pressure by correcting the operation amount of the pressurizing unit based on the difference between the internal resistance measurement value and the internal resistance estimated value at the target confining pressure.

13. The battery system according to any one of claims 1 to 11, The determination unit determines to prohibit charging and discharging of the all-solid-state battery when a difference between the internal resistance measurement value and the internal resistance estimation value at the target confinement pressure is equal to or greater than a predetermined value.

Images