JP2012026771A - Secondary battery apparatus and vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a secondary battery apparatus for estimating a charging state highly accurately, and a vehicle.SOLUTION: The present invention relates to a secondary battery apparatus including: a battery set 1 including a plurality of secondary battery cells BTs; a current measuring means 3 for measuring a current flowing to the battery set 1; a voltage measuring means 2 for measuring a voltage of each of the plurality of secondary battery cells BTs; a storage section 6 recording therein a table 61 of values of a ratio P of a charge resistance Rc and a discharge resistance Rd to a charging state of the secondary battery cells BTs; and an SOC estimation section 51 for calculating the ratio P of the charging resistance Rc and the discharge resistance Rd from the current value measured by the current measuring means 3 and the voltage value measured by the voltage measuring means, and determining the charging state while using the table 61.

Description

  Embodiments described herein relate generally to a secondary battery device and a vehicle.

  In a secondary battery device and a vehicle equipped with an assembled battery including a plurality of secondary battery cells, estimating a state of charge (SOC) that is a remaining chargeable amount of the secondary battery cells at an arbitrary time point Is required.

  As a method for estimating the state of charge of a secondary battery cell, for example, a method of performing a discharge test, a method of estimating by current integration, and a method of estimating using an open circuit voltage (OCV) have been proposed. Yes.

  The method of performing the discharge test is a method of estimating the state of charge by actually discharging the secondary battery cell. This method is difficult to perform while using the secondary battery cell. In addition, the estimation method based on current integration is difficult to determine a reference point when the secondary battery cell generally does not reach full charge or complete discharge. Accumulation errors accumulate and high-precision estimation is performed. Is difficult.

  When the open circuit voltage is used, it is difficult to estimate the state of charge by the open circuit voltage when the secondary battery cell is in use because the period during which the current is zero is required to some extent.

  In addition, as a method for estimating the state of charge of the secondary battery cell, a method using EMF (Electro-Motive Force), a method of measuring AC impedance, a method of obtaining by DC internal resistance, and artificial intelligence (neural network) are used. A method, a method using fuzzy logic, and a method using a Kalman filter have been proposed.

JP 2002-189066 A

  For example, in a secondary battery device for use in a vehicle such as a hybrid vehicle, it is rare for a secondary battery cell to reach full charge or complete discharge. Therefore, it is considered to use an open circuit voltage as a reference for charge state estimation. ing.

  However, the open circuit voltage cannot be directly measured unless there is a period of a certain length for which the current zero continues, and it may be difficult to estimate the state of charge. Also, when the OCV / SOC characteristic of the secondary battery cell includes a portion that is substantially flat, the difference in the charge state estimation value with respect to the slight difference in the open circuit voltage becomes large, thereby realizing highly accurate charge state estimation. It was difficult to do.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a secondary battery device and a vehicle that estimate the state of charge with high accuracy.

  The secondary battery device according to the first aspect of the present invention includes an assembled battery including a plurality of secondary battery cells, current measuring means for measuring a current flowing through the assembled battery, and voltages of the plurality of secondary battery cells. Voltage measuring means for measuring, a storage unit in which a table of ratio values of charge resistance and discharge resistance with respect to a charged state of the secondary battery cell is recorded, the current value measured by the current measuring means and the voltage measurement A SOC estimation unit that calculates a ratio between the charging resistance and the discharging resistance from the voltage value measured by the means and obtains a charging state using the table.

1 is a diagram schematically illustrating a configuration example of a vehicle according to an embodiment of the present invention. It is a block diagram which shows roughly the example of 1 structure of the secondary battery apparatus which concerns on one Embodiment of this invention. It is a figure which shows an example of the relationship between the internal resistance of a secondary battery cell, and SOC. It is a figure which shows an example of the relationship between the ratio of the charging resistance and discharge resistance of a secondary battery cell, and SOC. It is a figure for demonstrating the fixed period at the time of calculating | requiring SOC in the secondary battery apparatus which concerns on one Embodiment of this invention. It is a flowchart for demonstrating an example of the process for every sampling period in the secondary battery apparatus which concerns on one Embodiment of this invention. It is a flowchart for demonstrating an example of the process for every fixed period in the secondary battery apparatus which concerns on one Embodiment of this invention. It is a flowchart for demonstrating an example of the process for every fixed period in the secondary battery apparatus which concerns on one Embodiment of this invention. It is a figure which shows the example of a scatter diagram of the average value of an electric current, and the average value of a voltage in the secondary battery apparatus which concerns on one Embodiment of this invention. It is a figure which shows the example of a scatter diagram of the average value difference of an electric current, and the average value difference of a voltage in the secondary battery apparatus which concerns on one Embodiment of this invention. It is a figure which shows the example of a scatter diagram of the average value difference of an electric current, and the average value difference of a voltage in the secondary battery apparatus which concerns on one Embodiment of this invention. It is a figure which shows an example of an OCV / SOC characteristic.

  Hereinafter, a secondary battery device and a vehicle according to an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 schematically shows a configuration example of a vehicle according to an embodiment of the present invention. The vehicle according to the present embodiment is, for example, an electric vehicle or a hybrid vehicle, and has a secondary battery device mounted thereon.

  The vehicle includes an assembled battery module 400, a battery management device 300 that controls the operation of the assembled battery module 400, an operation control unit 500, a motor 600 to which power is supplied from the assembled battery module 400, an upper control circuit 700, A chassis 1000 and drive wheels WR and WL are provided.

  The assembled battery module 400 includes the assembled battery 1 (shown in FIG. 2) including a plurality of secondary battery cells BT. The positive terminal and the negative terminal of the assembled battery module 400 are connected to the operation control unit 500.

  The battery management device 300 is supplied with the voltage values of the plurality of secondary battery cells BT, the current value flowing through the assembled battery 1, and the temperature value near the assembled battery 1 from the assembled battery module 400, and charging and discharging the assembled battery 1. Etc. are managed.

  The operation control unit 500 includes an inverter, converts the voltage supplied from the assembled battery module 400, and receives an operation command to perform output current / voltage level control and phase control. The output of the operation control unit 500 is supplied to the motor 600 as drive power. The rotation of the motor 600 is transmitted to the drive wheels WR and WL via, for example, a differential gear unit.

  The upper control circuit 700 is configured to receive data of a plurality of secondary battery cells BT from the battery management device 300 and control the operation of the battery management device 300.

  FIG. 2 schematically shows a configuration example of a secondary battery device according to an embodiment of the present invention.

    The secondary battery device according to the present embodiment includes an assembled battery module 400 and a battery management device 300.

  The assembled battery module 400 includes an assembled battery 1 including a plurality of secondary battery cells BT, a voltage measuring circuit 2 that detects voltages of the plurality of secondary battery cells BT, and a temperature detection unit 4 disposed in the vicinity of the assembled battery. And current measuring means 3 for measuring the current flowing through the assembled battery 1.

  The battery management device 300 includes a control unit 5, a storage unit 6, and a communication interface 7 that performs communication with the host control circuit 700.

  The storage unit 6 is provided for each temperature range of the secondary battery cells BT with respect to the relationship between the charging state R and the ratio P (Rc / Rd) of the charging resistance Rc and discharging resistance Rd of the plurality of secondary battery cells BT. A plurality of tables 61 are provided. The storage unit 6 is, for example, an EEPROM (Electronically Erasable and Programmable Read Only Memory).

  The control unit 5 calculates the charging resistance Rc and the discharging resistance Rd of the secondary battery cell BT, and uses the ratio P between the charging resistance Rc and the discharging resistance Rd to correspond from the table 61 stored in the storage unit 6. An SOC estimation unit 51 for obtaining the state of charge is provided. The SOC estimation unit 51 outputs the obtained charging state to the communication interface 7.

  The communication interface 7 outputs the charge state of the secondary battery cell BT output from the control unit 5 to the upper control circuit 700 and outputs a control signal from the upper control circuit 700 to the control unit 5.

  FIG. 3 shows an example of the relationship between the internal resistance of the secondary battery cell BT and the state of charge. In FIG. 3, the horizontal axis is the charged state, the vertical axis is the internal resistance, the relationship between the internal resistance (discharge resistance) Rd and the charged state when the current flowing through the assembled battery 1 is in the discharging direction, and the assembled battery 1 6 shows the relationship between the internal resistance (charging resistance) Rc and the state of charge when the voltage flowing through is in the charging direction.

  The internal resistance Rd at the time of discharging increases when the charging state of the secondary battery cell BT is small, and decreases when the charging state is large. The internal resistance Rc at the time of charging decreases when the charging state of the secondary battery cell BT is small, and increases when the charging state is large.

  In addition, the slope of the characteristics of the charging resistor Rc with respect to the charging state is small when the charging state is small, and is large when the charging state is large. The slope of the characteristic of the discharge resistor Rd with respect to the charged state increases when the charged state is small, and increases when the charged state is large. The internal resistance Rd during discharging and the internal resistance Rc during charging are balanced in the vicinity of 50% of the charged state.

  FIG. 4 shows an example of the relationship (P / SOC characteristic) of the ratio P (Rc / Rd) of the charging resistance Rc and the discharging resistance Rd to the charging state of the secondary battery cell BT for each temperature of the secondary battery cell BT. Show. The ratio P between the charging resistance Rc and the discharging resistance Rd becomes a monotonically increasing characteristic with respect to the charged state of the secondary battery cell BT. The slope of the charging state with respect to the charging state with the ratio P of the charging resistance Rc to the discharging resistance Rd is always a certain value or more regardless of the size of the charging state, and the value of the ratio P is approximately 1 near 50% of the charging state. .

  Next, the operation of the control unit 5 when estimating the state of charge of the secondary battery cell to be evaluated in the secondary battery device and the vehicle will be described with reference to the drawings.

  In FIG. 5, an example of the timing chart at the time of calculating the charge condition of the some secondary battery cell BT is shown. The fixed period processing of SOC estimation is performed every three different periods T1, T2, and T3. The periods T1, T2, and T3 are the period T1 <the period T2 <the period T3, the period T2 includes a plurality of periods T1, and the period T3 includes a plurality of periods T2. For example, the period T1 is 0.1 second, the period T2 is 1 second, and the period T3 is 1 minute. The SOC estimation unit 51 of the control unit 5 performs the calculation process of the state of charge of the secondary battery cell BT as follows in each of the period T1, the period T2, and the period T3.

  FIG. 6 is a flowchart for explaining an example of processing for each cycle T1. The SOC estimation unit 51 obtains the voltage value of the secondary battery cell BT from the voltage measurement circuit 2 (step STA1), obtains the current value from the current measurement unit 3 (step STA2), and then obtains the secondary battery from the temperature measurement unit 4. The temperature values of the cell BT are acquired (step STA3), and time stamps are attached to these measured values and stored in the storage unit 6 (step STA4).

  FIG. 7 shows a flowchart for explaining an example of processing for each cycle T2. The SOC estimation unit 51 first calculates an average value Vave (N) of the plurality of secondary battery cell voltages stored in the latest past cycle T2 (step STB1), and calculates the plurality of current values stored in the latest past cycle T2. An average value Iave (N) is calculated (step STB2), and an average value Tave (N) of the temperature values of the plurality of secondary battery cells stored in the latest past cycle T2 is calculated (step STB3).

  FIG. 9 shows an example of a graph in which the values calculated for each period T2 are plotted with the average value Iave of the current being the horizontal axis and the average value Vave of the voltage being the vertical axis. The plot in the first quadrant of FIG. 9 represents the current average value Iave (N) and the voltage average value Vave (N) when the secondary battery cell BT is charged. The plot in the fourth quadrant of FIG. 9 represents the current average value Iave (N) and the voltage average value Vave (N) when the secondary battery cell BT is discharged.

  Further, after that, the SOC estimation unit 51 calculates a differential voltage value ΔVave (N) obtained by subtracting Vave (N−1) obtained in the latest past cycle T2 from the average value Vave (N) (step STB4).

  Similarly, the SOC estimation unit 51 calculates a differential current value ΔIave (N) obtained by subtracting the average value Iave (N−1) obtained in the latest past cycle T2 from the average value Iave (N) (step STB5). .

  The SOC estimation unit 51 associates the set data of the differential voltage value ΔVave (N) and the differential current value ΔIave (N) with the average value Tave (N) of the temperature values, and the average value Iave (N) is a positive value. If there is, it is stored in the charge side data area (step STB6).

  The SOC estimation unit 51 associates the set data of the differential voltage value ΔVave (N) and the differential current value ΔIave (N) with the average value Tave (N) of the temperature values, and the average value Iave (N) is a negative value. If there is, it is stored in the discharge side data area (step STB7).

  Here, when the period T2 is lengthened, the regression correlation when obtaining the resistance value decreases. On the other hand, when the period T2 is short, for example, when the period T2 and the period T1 are equal, the correlation of regression when obtaining the resistance value may be reduced due to the influence of the difference between the current change timing and the sampling timing.

Hereinafter, an example in which the determination coefficient R ² (the square of the correlation coefficient) when the length of the period T2 is changed is calculated using actual test data is shown. The coefficient of determination R ^2, the correlation is 1 in the case of maximum.

When T1 = 0.1 s and T2 = 0.1 s, R ² (determination coefficient) = 0.7795
When T1 = 0.1 s and T2 = 0.2 s, R ² (determination coefficient) = 0.5884
When T1 = 0.1 s and T2 = 0.3 s, R ² (determination coefficient) = 0.9344
When T1 = 0.1 s and T2 = 0.4 s, R ² (determination coefficient) = 0.9491
When T1 = 0.1 s and T2 = 0.5 s, R ² (determination coefficient) = 0.9697
When T1 = 0.1 s and T2 = 1 s, R ² (determination coefficient) = 0.9768
When T1 = 0.1 s and T2 = 2 s, R ² (determination coefficient) = 0.9694
When T1 = 0.1 s and T2 = 5 s, R ² (determination coefficient) = 0.9549
When T1 = 0.1 s and T2 = 10 s, R ² (determination coefficient) = 0.9257
When T1 = 0.1 s and T2 = 20 s, R ² (determination coefficient) = 0.9135
According to an example of the result using the actual test data, the correlation coefficient is maximized when the period T2 is 10 times the period T1. The value of the period T2 in which the correlation of the regression is greater (e.g., coefficient of determination R ² is 0.95 or higher) was 50 times or less in the range 5 or more times the value of the period T1. Therefore, the charging state can be estimated with higher accuracy by setting the range of the value of the cycle T2 to be not less than 5 times and not more than 50 times the value of the cycle T1.

  FIG. 8 shows a flowchart for explaining an example of processing for each cycle T3. The SOC estimation unit 51 obtains the charging resistance Rc (t) from the differential set data group in the charging side data region of the differential voltage value ΔVave (N) and the differential current value ΔIave (N) stored in the latest past period T3. (Step STC1).

  FIG. 10 shows an example of a graph in which a set data group of the differential voltage value ΔVave (N) and the differential current value ΔIave (N) on the charging side is plotted. For example, as shown in FIG. 10, when a set data group of the differential voltage value ΔVave (N) and the differential current value ΔIave (N) is stored, the SOC estimation unit 51 uses a regression line (ΔVave of these set data groups). = Rc × ΔIave) to obtain the charging resistance Rc (t).

  Subsequently, the SOC estimation unit 51 obtains the discharge resistance Rd (t) from the difference set data group in the discharge side data region of the difference voltage value ΔVave (N) and the difference current value ΔIave (N) stored in the past period T3. Obtained (step STC2).

  FIG. 11 shows an example of a graph plotting a set data group of the differential voltage value ΔVave (N) and the differential current value ΔIave (N) in the data area on the discharge side. For example, as shown in FIG. 11, when a set data group of the differential voltage value ΔVave (N) and the differential current value ΔIave (N) is stored, the SOC estimation unit 51 uses a regression line (ΔVave = The discharge resistance Rd (t) is obtained from the slope of Rd × ΔIave).

  The SOC estimating unit 51 stores the obtained charging resistance Rc (t) and discharging resistance Rd (t) in the storage unit 6 together with the corresponding temperature average value Tave (t) (step STC3). Then, the SOC estimation unit 51 refers to the table 61 of the ratio (Rc / Rd) of the charging resistance Rc to the discharging resistance Rd with respect to the charging state for each temperature average value Tave (t), and the current secondary battery cell The state of charge of BT is obtained (step STC4).

  The SOC estimation unit 51 stores in the storage unit 6 the state of charge obtained for the plurality of secondary battery cells BT. When requested by the upper control circuit 700 via the communication interface 7, the control circuit 5 transmits the charge state values of the plurality of secondary battery cells BT stored in the storage unit 6 to the upper control circuit 700. . The host control circuit 700 controls the battery management device 300 based on the charge state values of the plurality of secondary battery cells BT received from the control circuit 5.

  Note that the period T3 is preferably in the range of 10 to 200 times the period T2. When the number of difference set data in the period T3 is small on both the charging side and the discharging side, the variation in estimated values increases. On the other hand, if the period T3 is too large, the timing at which the estimated value is obtained becomes late with respect to, for example, the intermediate timing of the estimation target data period. As a result, the state of charge changes within the period T3, making it difficult to estimate with high accuracy. Therefore, it is possible to realize a highly accurate estimation of the state of charge with little time delay by defining the period T3 period as an appropriate range as a ratio to the period T2.

  Moreover, in the secondary battery device according to the present embodiment, the SOC estimation unit 51 has both the average value difference group data on the charging side and the average value difference group data on the discharge side both in a certain number or more in one cycle T3. The remaining amount estimation may be performed only in some cases.

  In addition, when the direction of the current flowing through the assembled battery 1 is violently switched between the charging direction and the discharging direction, difference assembled data may not be obtained. For example, when the current direction is reversed every sampling cycle, the difference combination data may not be obtained. In such a case, the number of difference pair data is not sufficient, and it is difficult to estimate the state of charge with high accuracy. By defining the minimum number of average value difference combination data on each of the charge side and the discharge side, it is possible to prevent variation in estimated values from increasing and to realize highly accurate SOC estimation.

  In addition, when the number of difference set data is not sufficient, the SOC estimation part 51 may be comprised so that a charge condition may be calculated | required with another system. For example, the SOC estimation unit 51 may be configured to obtain the state of charge from the integrated current value or to obtain the state of charge from the open circuit voltage.

  In addition, the SOC estimation unit 51 may be configured to stand by until the number of difference pair data is sufficiently calculated, and to obtain the state of charge when a sufficient number of data is calculated.

  Further, in the secondary battery device according to the present embodiment, the SOC estimation unit 51 estimates the remaining amount according to the range of the value P (Rc / Rd) of the obtained charging resistance value Rc and discharging resistance value Rd. You may be comprised so that a method may be used properly.

  The SOC estimation unit 51 sets a specific value in the range of the ratio P in the range of 0.5 to 0.9 as the lower limit, and sets a specific value in the range of 1.1 to 2.0 as the upper limit. The remaining amount is estimated using the ratio P, and the ratio P is set when the range P is within the range (minimum range 0.9 to 1.1 and maximum 0.5 to 2.0). The remaining amount may be estimated by another method when it is out of the range. In this case, the upper limit value and the lower limit value are set according to the slope of the OCV / SOC characteristic of the secondary battery cell BT.

  The region where the slope of the OCV / SOC characteristic is substantially flat is generally near the center of the SOC axis, and the slope of the OCV / SOC characteristic becomes large when the state of charge is small or large. Thus, the OCV / SOC characteristics are classified according to their slopes, and a good state of charge estimation over the entire SOC region can be realized by combining the SOC estimation method using the open circuit voltage and the SOC estimation method using the ratio P. .

  In this case, when the slope of the OCV / SOC characteristic is greater than or equal to a predetermined value, the SOC estimation unit 51 obtains the state of charge from the open circuit voltage, and when the slope of the OCV / SOC characteristic is less than the predetermined value, the ratio P To determine the state of charge.

  As described above, by estimating the charge state using the SOC characteristic of the ratio P (Rc / Rd) of the charge resistance Rc and the discharge resistance Rd, the error of the ratio P is extremely reduced as the charge state error. It is possible to estimate the state of charge with high accuracy without being enlarged.

  FIG. 12 shows an example of OCV / SOC characteristics. For example, the open circuit voltage is 2.345 V when the SOC is 10%, and the open circuit voltage is 2.353 V when the SOC is 40%. In this case, the open circuit voltage at 40% SOC is 1.0034 times (100.34%) (2.353V / 2.345V) the open circuit voltage at 10% SOC.

  On the other hand, for example, the ratio P is 0.46 when the SOC is 10%, and the ratio P is 0.92 when the SOC is 40%. In this case, the ratio P value at 40% SOC is twice (200%) (0.92 / 0.46) the ratio P value at 10% SOC.

  From the viewpoint of SOC estimation accuracy, using the OCV / SOC characteristic, when an open circuit voltage is used, 0.008V (ΔOCV = 2.353-2.345), that is, an error of 0.34% Leads to an estimated error of 30% SOC (ΔSOC), but when the ratio P value is used, if the ratio P value is twice different (that is, there is a 100% error), the SOC 30% error (ΔSOC) ) Will occur.

  That is, the open circuit voltage error (ΔOCV) for generating the same SOC 30% error is 0.34%, and the ratio P value error (ΔP) for generating the same error is a value of about 1/300 of 100%. It is. As described above, the charging state estimation error is greatly improved to about 1/300 by using the ratio P value instead of the open circuit voltage to obtain the charging state.

  As described above, according to the secondary battery device and the vehicle according to the present embodiment, by calculating the charging resistance Rc and the discharging resistance Rd and further obtaining the charging state by the ratio P (Rc / Rd), A secondary battery device and a vehicle that estimate the state of charge with high accuracy can be provided.

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

  BT ... secondary battery cell, Rc ... charging resistance, Rd ... discharge resistance, P (Rc / Rd) ... ratio, T1 ... first cycle, T2 ... second cycle, T3 ... third cycle, Vave ... voltage average value, Iave ... current average value, ΔVave ... differential voltage value, ΔIave ... differential current value, Tave ... temperature average value, 1 ... assembled battery, 2 ... voltage measurement circuit (voltage measurement means), 3 ... current measurement section (current measurement means) DESCRIPTION OF SYMBOLS 4 ... Temperature measurement part (temperature detection means) 5 ... Control part, 6 ... Memory | storage part, 7 ... Communication interface, 51 ... SOC estimation part, 61 ... Table, 300 ... Battery management apparatus, 400 ... Assembly battery module, 500 ... Operation control unit, 600: motor, 700: host control circuit, 1000: chassis.

Claims (4)

An assembled battery including a plurality of secondary battery cells;
Current measuring means for measuring a current flowing through the assembled battery;
Voltage measuring means for measuring the voltage of each of the plurality of secondary battery cells;
A storage unit in which a table of values of a ratio of charging resistance and discharging resistance with respect to a charging state of the secondary battery cell is recorded;
An SOC estimation unit for calculating a ratio between the charging resistance and the discharging resistance from the current value measured by the current measuring unit and the voltage value measured by the voltage measuring unit, and obtaining a charging state using the table; A secondary battery device comprising: Temperature measuring means for measuring the temperature in the vicinity of the assembled battery,
In the storage unit, a plurality of the tables provided for each temperature range is recorded,
The secondary battery according to claim 1, wherein the SOC estimation unit is configured to obtain a state of charge using the table corresponding to a temperature range including the temperature measured by the temperature measurement unit. apparatus. The SOC estimation unit causes the storage unit to store set data of the current value measured by the current measurement unit and the voltage value measured by the voltage measurement unit in the first period,
In a second cycle including a plurality of the first cycles, an average current value obtained by averaging the current values stored in the plurality of first cycles and an average voltage value obtained by averaging the voltage values are calculated, and the average current value and the Average data obtained in the second cycle nearest to the difference voltage value and average current value obtained by subtracting the average voltage value obtained from the average voltage value in the latest second cycle from the average voltage value stored in the storage unit. Calculate the pair data with the difference current value obtained by subtracting the current value,
In a third cycle including a plurality of the second cycles, a charging resistance is obtained from an inclination of a regression line of data when charging the set data of the differential voltage value and the differential current value, and the differential voltage value and the differential current are obtained. The discharge resistance is obtained from the slope of the regression line of the data at the time of discharging the set data with the value, and the charge state of the secondary battery cell is obtained from the table using the ratio of the charge resistance and the discharge resistance. The secondary battery device according to claim 1, wherein   A vehicle comprising the secondary battery device according to any one of claims 1 to 3.

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