Power storage pack

Abstract

According to the present invention, a control unit acquires a measurement value from a temperature sensor via signal lines of a plurality of systems. A first system does not provide high-frequency filters on both a positive signal line connected to one terminal of the temperature sensor and a negative signal line connected to the other terminal. A second system is provided with a high-frequency filter on either of a plus signal line connected to one terminal of the temperature sensor and a minus signal line connected to the other terminal. A third system is provided with high-frequency filters on both a positive signal line connected to one terminal of the temperature sensor and a negative signal line connected to the other terminal. The control unit compares the two or more measured values acquired from the signal lines of the two or more systems, and determines whether the measured values include noise.

Description

Energy storage pack

[0001] The present disclosure relates to an electricity storage pack including a temperature sensor.

[0002] Battery packs typically incorporate temperature sensors using negative temperature coefficient (NTC) thermistors to measure the temperatures of the battery, bus bars, and other components. When normal (differential) mode (see Figure 2A) or common mode (see Figure 2B) noise penetrates the temperature sensor, changing the current flowing through or voltage applied to the thermistor. This can result in errors in the temperature measurement value from the measurement circuit. These temperature measurement errors can lead to control errors in downstream microcontrollers and reduced accuracy in estimating the SOC.

[0003] Patent Document 1 discloses a method for determining whether the thermistors TH1 to TH3 are abnormal by comparing the relationship between the high and low levels of the temperature data of the thermistors TH1 to TH3 that have been preset with the relationship between the high and low levels of the temperature data of the thermistors TH1 to TH3 that have been acquired (see Figures 1 and 2 of Patent Document 1).

[0004] Patent Document 2 discloses a temperature abnormality detection sensor in which multiple temperature detection units are connected in series. Each temperature detection unit is composed of an anti-fuse circuit in which an anti-fuse element and a resistive element are connected in series, and a PTC thermistor connected in parallel. When the temperature is normal, the combined resistance of the temperature detection units is approximately equal to the resistance of the PTC thermistor. When the temperature is abnormal, the anti-fuse element transitions from an insulating state to a conductive state, and the combined resistance of the temperature detection units is approximately equal to the resistance of the resistive element. By setting the resistance of the resistive element of each temperature detection unit to a different value, it is possible to identify which temperature detection unit is abnormal (see Figure 1 of Patent Document 2).

[0005] JP 2012-122930 A JP 2013-24718 A

[0006] The methods disclosed in Patent Documents 1 and 2 are based on the assumption that multiple temperature sensors are installed, and are difficult to apply when only one temperature sensor is installed. The present inventor has developed a highly versatile technology that can accurately determine the effect of noise on the measurement value of a temperature sensor.

[0007] The present disclosure has been made in consideration of these circumstances, and its purpose is to provide a technique for determining with high accuracy the effect of noise on the measurement value of a temperature sensor.

[0008] To solve the above problem, an electricity storage pack according to an aspect of the present disclosure includes a temperature sensor for measuring a temperature at a predetermined position within the electricity storage pack, and a control unit that acquires measurement values ​​from the temperature sensor via multiple signal lines. The multiple signal lines include two or more signal lines from a first system in which neither a positive signal line connected to one terminal of the temperature sensor nor a negative signal line connected to the other terminal is provided with a high-frequency filter, a second system in which a high-frequency filter is provided in either the positive signal line connected to one terminal of the temperature sensor or the negative signal line connected to the other terminal, and a third system in which a high-frequency filter is provided in both the positive signal line connected to the one terminal of the temperature sensor and the negative signal line connected to the other terminal, and the control unit compares two or more measurement values ​​acquired from the signal lines of the two or more systems to determine whether the measurement values ​​contain noise.

[0009] According to the present disclosure, the influence of noise on the measurement value of a temperature sensor can be determined with high accuracy.

[0010] 2A is a diagram for explaining the configuration of a battery pack according to an embodiment; FIG. 2A is a diagram showing a propagation path of normal mode noise that enters a temperature sensor; FIG. 2B is a diagram showing a propagation path of common mode noise that enters a temperature sensor; FIG. 2B is a diagram showing an electrical connection configuration of a thermistor; FIG. 2C is a graph showing the relationship between the temperature and resistance value of a thermistor, and the relationship between thermistor resistance value and output voltage; FIG. 2D is a diagram showing a first configuration example of a temperature measurement system in a battery pack according to an embodiment; FIG. 2E is a graph showing a comparison result of temperature measurement values ​​acquired from three signal lines and a determination content according to the comparison result; FIG. 2F is a diagram showing a second configuration example of a temperature measurement system in a battery pack according to an embodiment; FIG. 2G is a graph showing a comparison result of temperature measurement values ​​acquired from two signal lines and a determination content according to the comparison result; FIG. 2H is a diagram showing a third configuration example of a temperature measurement system in a battery pack according to an embodiment;

[0011] FIG. 1 is a diagram illustrating the configuration of a battery pack 10 according to an embodiment. The battery pack 10 can be used as a power source for electric mobility devices such as electric bicycles, electric motorcycles, and small multicopters (also called drones). The battery pack 10 may be a detachable, portable type, or may be fixed to a device such as an electric mobility device. The use of the battery pack 10 is not limited, and the battery pack 10 may be installed in any device.

[0012] The battery pack 10 includes a battery module 11 and a battery management device 12. The battery module 11 includes multiple cells E1-En connected in series. The number of cells connected in series is determined by the load specifications. The cells may be lithium-ion battery cells, nickel-metal hydride battery cells, lead-acid battery cells, or the like. In the following description, an example using lithium-ion battery cells (nominal voltage: 3.6-3.7V) is assumed. Note that in each series stage of cells, multiple cells may be connected in parallel to increase capacity.

[0013] A power switch Sp that switches between conduction and non-conduction with the load is inserted in a power line connecting the battery module 11 and a load (not shown) connected to the battery pack 10. A semiconductor switch or a relay can be used as the power switch Sp.

[0014] The battery management device 12 includes a measurement unit 13 and a control unit 14. The measurement unit 13 is configured with an AFE (Analog Front End) IC or an ASIC (Application Specific Integrated Circuit), and the control unit 14 is configured with a microcontroller.

[0015] The measurement unit 13 is connected to each node of the multiple cells E1-En connected in series by multiple voltage measurement lines, and measures the voltage of each cell E1-En by measuring the voltage between each two adjacent voltage measurement lines.

[0016] The measurement unit 13 includes a multiplexer and an A / D converter. The multiplexer outputs the voltages of the multiple cells E1-En to the A / D converter in a predetermined order. The A / D converter converts the analog voltages input from the multiplexer into digital values. The measurement unit 13 transmits the voltage values ​​of the cells E1-En, converted into digital values, to the control unit 14 via a serial communication interface. The measurement unit 13 and the control unit 14 may be connected by an analog communication line, and the A / D converter may be provided within the control unit 14.

[0017] The measurement unit 13 measures the current flowing through the battery module 11. A shunt resistor Rs is connected to the power line connecting the battery module 11 to the load. A differential amplifier (not shown) amplifies the voltage across the shunt resistor Rs and outputs it to an A / D converter in the measurement unit 13. The A / D converter converts the analog voltage indicating the current flowing through the battery module 11, which is input from the differential amplifier, into a digital value. The measurement unit 13 transmits the current value converted into a digital value to the control unit 14 via a serial communication interface. Note that the measurement unit 13 and control unit 14 may be connected by an analog communication line, and the A / D converter may be provided within the control unit 14.

[0018] A temperature sensor T1 is installed on the surface of the battery module 11. The divided voltage of the temperature sensor T1 and a voltage dividing resistor (see FIG. 3) is input to the measurement unit 13. An A / D converter in the measurement unit 13 converts the input analog voltage indicating the temperature into a digital value. The measurement unit 13 transmits the converted digital temperature value to the control unit 14 via a serial communication interface. Alternatively, the measurement unit 13 and control unit 14 may be connected by an analog communication line, and the A / D converter may be provided within the control unit 14.

[0019] The control unit 14 manages the states of the cells E1-En based on the voltage values ​​of the cells E1-En, the current values ​​flowing through the battery module 11, and the temperature values ​​of the battery module 11 received from the measurement unit 13. When the control unit 14 detects overcharge, overdischarge, overcurrent, abnormally high temperature, or abnormally low temperature, it sends a shut-off signal for the power switch Sp to the measurement unit 13 to turn off the power switch Sp.

[0020] The control unit 14 can estimate the SOC by combining the OCV (Open Circuit Voltage) method and the current integration method. The OCV method is a method for estimating the SOC based on the measured cell OCV and the cell's SOC-OCV curve. The cell's SOC-OCV curve is created in advance by the battery manufacturer based on characteristic tests and is registered in the control unit 14 at the time of shipment.

[0021] The current integration method is a method for estimating the SOC based on the OCV at the start of charging and discharging the cell and the integrated value of the measured current. In the current integration method, current measurement errors accumulate as the charging and discharging time increases. Therefore, it is preferable to use a weighted average of the SOC estimated by the current integration method and the SOC estimated by the OCV method. When estimating the SOC, the control unit 14 preferably corrects the SOC according to the temperature measured by the temperature sensor T1.

[0022] In this embodiment, in order to determine the reliability of the measurement value of the temperature sensor T1, a mechanism for determining the effect of noise on the measurement value of the temperature sensor T1 is introduced. The noise that enters the temperature sensor T1 is classified into normal mode noise and common mode noise.

[0023] 2A is a diagram showing the propagation path of normal mode noise entering the temperature sensor T1. FIG. 2B is a diagram showing the propagation path of common mode noise entering the temperature sensor T1. In the following, in this embodiment, an example is assumed in which the temperature sensor T1 includes a thermistor Rt with NTC characteristics.

[0024] 2A, normal mode noise occurs when noise is superimposed on the signal line connecting the measurement unit 13 and the temperature sensor T1. The normal mode noise propagates in a circular manner through the positive and negative signal lines connecting the measurement unit 13 and the temperature sensor T1.

[0025] 2B, a path through which a high-frequency current flows is formed via the parasitic capacitance Cp between the circuit board on which the signal line connecting the measurement unit 13 and the temperature sensor T1 is mounted and the chassis ground. When high-frequency noise is superimposed on the path formed between this circuit board and the chassis ground, common mode noise is generated. Common mode noise itself does not cause a potential difference in the thermistor Rt, so it does not cause any problems. However, if there is a location where the characteristic impedance is discontinuous due to structural differences between the circuit board and the harness, the common mode noise is converted into normal mode noise, and a high-frequency current flows through the thermistor Rt.

[0026] 3 is a diagram showing the electrical connection configuration of the thermistor Rt. The thermistor Rt is used by connecting it in series with a voltage-dividing resistor Rd. The series circuit of the thermistor Rt and voltage-dividing resistor Rd is connected between a power supply potential VDD that supplies a bias voltage to the thermistor Rt and ground potential. The divided voltage of the thermistor Rt and the voltage-dividing resistor Rd is output to an A / D converter 141 as a value indicating the temperature of the object being measured by the thermistor Rt.

[0027] The resistance value Rs of the NTC thermistor Rt can be calculated using the following formula (1).

[0028] Rs = Rref exp(B * ((1 / Te) - (1 / Tref))) (Equation 1) Te: temperature (K) Rs: thermistor resistance value (Ω) at temperature Te Tref: reference temperature (K) Rref: reference resistance value (Ω) at reference temperature Tref B: constant (physical property representing the sensitivity of the thermistor to temperature changes) Figure 4 is a graph showing the relationship between the temperature and resistance value of a certain thermistor, and the relationship between thermistor resistance value and output voltage. This thermistor has a reference resistance value of 10 kΩ at a temperature of 25°C, and a B constant set to 3500.

[0029] Tref: 298 (K) = 25 (°C) + 273 Rref: 10,000 (Ω) B: 3,500 Substituting these values ​​into the above (Equation 1) gives the following (Equation 2), which gives the relationship between temperature and thermistor resistance shown in Figure 4.

[0030] Rs=10000·exp(3500*((1 / Te)-(1 / 298))) (Equation 2) When this thermistor is used as the thermistor Rt in FIG. 3, the bias voltage supplied to thermistor Rt is set to 3.3 V, and the resistance value of voltage dividing resistor Rd is set to 10 kΩ, the divided voltage is the output voltage shown in FIG. 4. Based on the output voltage value converted by A / D converter 141 and the characteristics shown in FIG. 4, control unit 14 can estimate the temperature of the object to be measured by thermistor Rt.

[0031] FIG. 5 is a diagram showing a first configuration example of a temperature measurement system in a battery pack 10 according to an embodiment. In the battery pack 10 according to the present embodiment, the control unit 14 acquires measurement values ​​from the temperature sensor T1 via multiple signal lines. In the first configuration example, measurement values ​​are acquired via three signal lines. (1) The first system is a system in which a high-frequency filter (high-frequency noise filter) is not provided on either the positive signal line connected to one terminal of the thermistor Rt or the negative signal line connected to the other terminal of the thermistor Rt. (2) The second system is a system in which a high-frequency filter is provided on either the positive signal line connected to one terminal of the thermistor Rt or the negative signal line connected to the other terminal of the thermistor Rt. (3) The third system is a system in which a high-frequency filter is provided on both the positive signal line connected to one terminal of the thermistor Rt and the negative signal line connected to the other terminal of the thermistor Rt.

[0032] Three positive signal lines connect the positive electrode of thermistor Rt and the power supply potential in parallel. Three negative signal lines connect the negative electrode of thermistor Rt and the voltage division point N1 in parallel. The voltage at voltage division point N1 is output to an A / D converter 141 in the control unit 14.

[0033] In this embodiment, we will assume an example in which ferrite beads B2 and B3 are used as high-frequency filters. In the second system, ferrite bead B2 is inserted in the positive signal line. In the third system, ferrite bead B3 is inserted in both the positive and negative signal lines.

[0034] The ferrite beads B2 and B3 suppress noise by converting magnetic energy generated by noise currents into heat. This allows the ferrite beads B2 and B3, i.e., the high-frequency filter, to function as a high-frequency noise filter that suppresses normal mode noise and common mode noise. The closer the ferrite beads B2 and B3 are located to the thermistor Rt, the greater the noise suppression effect. Note that a choke coil or damping resistor may be used as a high-frequency filter instead of the ferrite beads.

[0035] A selection switch is connected to each signal line of each system. In configuration example 1, a first selection switch S1 is connected to the negative signal line of the first system, and a second selection switch S2 is connected to the negative signal line of the second system. A third selection switch S3 is connected to the negative signal line of the third system at a position closer to the voltage division point N1 than the ferrite bead B3.

[0036] Analog switches (e.g., MOSFETs) are used for the first selection switch S1 to the third selection switch S3. The control unit 14 sends control signals for the first selection switch S1 to the third selection switch S3 to the measurement unit 13 to switch the first selection switch S1 to the third selection switch S3 in a time-division manner. The control unit 14 acquires the measurement values ​​that have passed through each system in a time-division manner.

[0037] For common-mode noise, the noise propagates in the same direction on the positive and negative signal lines of the thermistor Rt. Therefore, in the third system, the magnetic fluxes generated by the self-induction of the ferrite bead B3 reinforce each other, increasing impedance and suppressing common-mode noise. On the other hand, for normal-mode noise, the noise propagates in opposite directions on the positive and negative signal lines of the thermistor Rt. Therefore, the magnetic fluxes generated by the ferrite bead B3 are opposite in direction and cancel each other out, lowering impedance and suppressing normal-mode noise. In the second system, normal-mode noise is suppressed by the impedance of the ferrite bead B2, but common-mode noise circulating between the negative signal line and ground is not suppressed. In the first system, neither normal-mode noise nor common-mode noise is suppressed. The control unit 14 utilizes this property to compare two or more measurement values ​​acquired from signal lines of multiple systems to determine whether the measurement values ​​contain noise.

[0038] 6 is a graph summarizing the comparison results of the temperature measurement values ​​acquired from the three signal lines and the determination contents according to the comparison results. When the measurement value acquired from the first signal line (hereinafter referred to as Ch1 measurement value), the measurement value acquired from the second signal line (hereinafter referred to as Ch2 measurement value), and the measurement value acquired from the third signal line (hereinafter referred to as Ch3 measurement value) are substantially equal, the control unit 14 determines that the measurement values ​​do not contain significant noise.

[0039] The control unit 14 determines that the Ch1 measurement value predominantly contains normal mode noise when the difference between the Ch2 measurement value and the Ch3 measurement value is equal to or greater than a first set value and the difference between the Ch1 measurement value and the Ch3 measurement value is equal to or greater than a second set value. The first set value is set to a tolerance value at which the Ch2 measurement value and the Ch3 measurement value are considered to be substantially equal, and the second set value is set to a tolerance value at which the Ch1 measurement value and the Ch3 measurement value are considered to be substantially equal. The first set value and the second set value may be set to the same value or may be set to different values.

[0040] The control unit 14 determines that the Ch1 measurement value contains predominantly common-mode noise when the difference between the Ch2 measurement value and the Ch3 measurement value is equal to or greater than a first set value and the difference between the Ch1 measurement value and the Ch2 measurement value is equal to or greater than a third set value. The third set value is set to an allowable value at which the Ch1 measurement value and the Ch2 measurement value are considered to be substantially equal. The first set value, the second set value, and the third set value may be set to the same value or may be set to different values.

[0041] The control unit 14 treats the temperature measurement value during the period in which it is determined that the Ch1 measurement value contains significant noise as an invalid value and processes the temperature measurement value so that it is not reflected in calculations or control. If the state in which it is determined that the Ch1 measurement value contains significant noise continues for a certain period of time, the control unit 14 determines that an abnormality has occurred somewhere in the temperature measurement system. For example, there is a possibility that the temperature sensor T1 or the measurement unit 13 is malfunctioning.

[0042] 7 is a diagram showing a second example of a configuration of a temperature measurement system in the battery pack 10 according to the embodiment. In the second example, the control unit 14 acquires measurement values ​​via two signal lines, a second system and a third system.

[0043] 8 is a graph summarizing the comparison results of the temperature measurement values ​​acquired from the two signal lines and the determination contents according to the comparison results. If the difference between the Ch2 measurement value and the Ch3 measurement value is less than the first set value, the control unit 14 determines that the measurement value does not contain significant noise.

[0044] When the difference between the Ch2 measurement value and the Ch3 measurement value is equal to or greater than the first set value, the control unit 14 determines that the measurement value contains significant noise. In configuration example 2, it is not possible to determine whether normal mode noise or common mode noise is dominant.

[0045] The control unit 14 treats the temperature measurement value during the period in which it is determined that the Ch2 measurement value or the Ch3 measurement value contains significant noise as an invalid value and processes the temperature measurement value so as not to reflect it in calculations or control. If the state in which it is determined that the Ch2 measurement value or the Ch3 measurement value contains significant noise continues for a certain period of time, the control unit 14 determines that an abnormality has occurred somewhere in the temperature measurement system.

[0046] 9 is a diagram showing a third configuration example of a temperature measurement system in the battery pack 10 according to the embodiment. In the third configuration example, a thermistor Rt is provided for each system. When three systems are provided as shown in FIG. 9, a first thermistor Rt1, a second thermistor Rt2, and a third thermistor Rt3 are arranged adjacent to each other.

[0047] The first system outputs a divided voltage between the first thermistor Rt1 and the first voltage dividing resistor Rd1 as a Ch1 measurement value, the second system outputs a divided voltage between the second thermistor Rt2 and the second voltage dividing resistor Rd2 as a Ch2 measurement value, and the third system outputs a divided voltage between the third thermistor Rt3 and the third voltage dividing resistor Rd3 as a Ch3 measurement value.

[0048] When the characteristics of the first thermistor Rt1, the second thermistor Rt2, and the third thermistor Rt3 are the same, the voltage-dividing resistor Rd can be shared as shown in FIGS. 5 and 7 . When there is an error in the characteristics of the first thermistor Rt1, the second thermistor Rt2, and the third thermistor Rt3, the error can be adjusted by changing the resistance values ​​of the first voltage-dividing resistor Rd1, the second voltage-dividing resistor Rd2, and the third voltage-dividing resistor Rd3. The other circuit configurations and operations are the same as those of Configuration Example 1 shown in FIGS. 5 and 6 . Note that when the first thermistor Rt1, the first voltage-dividing resistor Rd1, and the first system signal line are not provided, the circuit configuration and operations are the same as those of Configuration Example 2 shown in FIGS. 7 and 8 .

[0049] As described above, according to this embodiment, by comparing temperature measurement values ​​of multiple systems with different high-frequency filter connection statuses, it is possible to determine with high accuracy the effect of noise on the measurement values ​​of the temperature sensor. In configuration examples 1 and 3, it is also possible to identify whether normal mode noise or common mode noise is dominant. In configuration examples 1 and 2, even if only one thermistor Rt is installed, it is possible to determine the effect of noise on the measurement values, making them highly versatile.

[0050] The present disclosure has been described above based on the embodiments. The embodiments are merely examples, and it will be understood by those skilled in the art that various modifications are possible in the combination of the respective components and processing steps, and that such modifications are also within the scope of the present disclosure.

[0051] In the above embodiment, an example has been described in which the temperature sensor T1 is installed on the surface of the battery module 11 to measure the temperature of the battery module 11. In this regard, temperature sensors may be installed at multiple locations on the battery module 11 to measure the temperature of each cell or several cells.

[0052] The temperature sensor may also be installed at a predetermined position other than the battery module 11 in the battery pack 10. For example, the temperature sensor may be installed on the circuit board of the measurement unit 13 to measure the temperature of the circuit board. Alternatively, the temperature sensor may be installed near the power switch Sp to measure the temperature of the power switch Sp.

[0053] In the above embodiment, an example has been described in which a temperature sensor T1 including a thermistor Rt is used. In this regard, a temperature sensor including a thermocouple may also be used. When a thermocouple is used, different metal wires are used for the positive and negative signal wires. An electromotive force corresponding to the temperature difference between the measurement point and the reference point is generated between the positive and negative signal wires. Because the generated electromotive force is weak, the voltage generated between the positive and negative signal wires is amplified by an amplifier (not shown) and output to the A / D converter 141.

[0054] In the above embodiment, an example has been described in which the battery pack 10 incorporating the battery module 11 is used. In this regard, a capacitor pack incorporating a capacitor module including an electric double layer capacitor cell, a lithium ion capacitor cell, or the like may also be used. In this specification, the battery pack and the capacitor pack are collectively referred to as a power storage pack.

[0055] The embodiment may be specified by the following items.

[0056] [Item 1] An electricity storage pack (10) comprising: a temperature sensor (T1) for measuring a temperature at a predetermined position within the electricity storage pack (10); and a control unit (14) that acquires measurement values ​​from the temperature sensor (T1) via multiple systems of signal lines, wherein the multiple systems of signal lines include signal lines of two or more systems: a first system in which a high-frequency filter is not provided on either a positive signal line connected to one terminal of the temperature sensor (T1) or a negative signal line connected to the other terminal; a second system in which a high-frequency filter (B2) is provided on either the positive signal line connected to one terminal of the temperature sensor (T1) or the negative signal line connected to the other terminal; and a third system in which a high-frequency filter (B3) is provided on both the positive signal line connected to one terminal of the temperature sensor (T1) and the negative signal line connected to the other terminal; and the control unit (14) compares two or more measurement values ​​acquired from the signal lines of the two or more systems to determine whether the measurement values ​​contain noise.

[0057] This makes it possible to determine with high accuracy whether the measurement value of the temperature sensor (T1) contains noise.

[0058] [Item 2] The electricity storage pack (10) according to Item 1, wherein two systems of signal lines, the second system and the third system, are provided as the plurality of systems of signal lines, and the control unit (14) determines that the measurement values ​​contain noise when a difference between two measurement values ​​acquired from the two systems of signal lines is equal to or greater than a set value.

[0059] This makes it possible to determine with high accuracy whether the measurement value of the temperature sensor (T1) contains noise while minimizing the addition of parts.

[0060] [Item 3] The electricity storage pack (10) according to Item 1, wherein three systems of signal lines, namely the first system, the second system, and the third system, are provided as the signal lines of the plurality of systems, and the control unit (14) determines that the measurement values ​​acquired from the signal lines of the first system contain normal mode noise when a difference between a measurement value acquired from the signal line of the second system and a measurement value acquired from the signal line of the third system is equal to or greater than a first set value and a difference between a measurement value acquired from the signal line of the first system and a measurement value acquired from the signal line of the third system is equal to or greater than a second set value, and determines that the measurement values ​​acquired from the signal line of the first system contain common mode noise when a difference between a measurement value acquired from the signal line of the second system and a measurement value acquired from the signal line of the third system is equal to or greater than a first set value and a difference between a measurement value acquired from the signal line of the first system and a measurement value acquired from the signal line of the second system is equal to or greater than a third set value.

[0061] This makes it possible to determine whether normal mode noise or common mode noise is dominant.

[0062] [Item 4] The electricity storage pack (10) according to Item 1, wherein switches (S1-S3) are connected to the signal lines of the plurality of systems, respectively, and the control unit (14) switches the switches (S1-S3) connected to the signal lines of the plurality of systems, respectively, in a time-division manner to acquire measurement values ​​via the systems in a time-division manner.

[0063] This allows the A / D converter installed at the subsequent stage to be shared by a plurality of systems.

[0064] [Item 5] The electricity storage pack (10) according to Item 1, wherein the control unit (14) processes the measurement value as an invalid value during a period in which it is determined that the measurement value contains noise.

[0065] This makes it possible to prevent control errors from occurring.

[0066] [Item 6] The electricity storage pack (10) according to Item 1, wherein the control unit (14) determines that an abnormality has occurred at any point in a temperature measurement system when a state in which it is determined that the measurement value contains noise continues for a certain period of time.

[0067] This makes it possible to monitor the presence or absence of noise and simultaneously perform fault diagnosis.

[0068] [Item 7] The electricity storage pack (10) according to Item 1, further comprising an electricity storage module (11) including a plurality of cells (E1-En), wherein the temperature sensor (T1) is installed in the electricity storage module (11).

[0069] This allows the temperature of the electricity storage module (11) to be measured with high accuracy.

[0070] [Item 8] The electricity storage pack (10) according to Item 1, wherein the high-frequency filters (B2, B3) are ferrite beads (B2, B3).

[0071] This ensures high impedance in the high frequency range.

[0072] REFERENCE SIGNS LIST 10 battery pack, 11 battery module, 12 battery management device, 13 measurement unit, 14 control unit, 141 A / D converter, T1 temperature sensor, Rt thermistor, Sp power switch, S1-S3 selection switch, E1-En cell, Rs shunt resistor, Rd voltage dividing resistor, B2, B3 ferrite beads.

Claims

1. An electricity storage pack comprising: a temperature sensor for measuring the temperature at a predetermined position within the electricity storage pack; and a control unit for acquiring measurement values ​​from the temperature sensor via multiple systems of signal lines, wherein the multiple systems of signal lines include signal lines of two or more systems selected from the following: a first system in which a high-frequency filter is not provided on either the positive signal line connected to one terminal of the temperature sensor or the negative signal line connected to the other terminal; a second system in which a high-frequency filter is provided on either the positive signal line connected to one terminal of the temperature sensor or the negative signal line connected to the other terminal; and a third system in which a high-frequency filter is provided on both the positive signal line connected to one terminal of the temperature sensor and the negative signal line connected to the other terminal; and the control unit compares two or more measurement values ​​acquired from the signal lines of the two or more systems to determine whether the measurement values ​​contain noise.

2. The electricity storage pack according to claim 1, wherein two systems of signal lines, the second system and the third system, are provided as the multiple systems of signal lines, and the control unit determines that the measurement values ​​contain noise when a difference between two measurement values ​​acquired from the two systems of signal lines is equal to or greater than a set value.

3. The electricity storage pack according to claim 1, wherein three systems of signal lines, namely the first system, the second system, and the third system, are provided as the multiple systems of signal lines, and the control unit determines that the measurement value acquired from the signal line of the first system contains normal mode noise when a difference between a measurement value acquired from the signal line of the second system and a measurement value acquired from the signal line of the third system is equal to or greater than a first set value and a difference between a measurement value acquired from the signal line of the first system and a measurement value acquired from the signal line of the third system is equal to or greater than a second set value, and determines that the measurement value acquired from the signal line of the first system contains common mode noise when a difference between a measurement value acquired from the signal line of the second system and a measurement value acquired from the signal line of the third system is equal to or greater than a first set value and a difference between a measurement value acquired from the signal line of the first system and a measurement value acquired from the signal line of the second system is equal to or greater than a third set value.

4. The electricity storage pack according to claim 1, wherein a switch is connected to each of the signal lines of the plurality of systems, and the control unit switches the switches connected to the signal lines of the plurality of systems in a time-division manner to acquire measurement values ​​passing through each of the plurality of systems in a time-division manner.

5. The electricity storage pack according to claim 1, wherein the control unit processes the measurement value as an invalid value during a period in which the measurement value is determined to contain noise.

6. The storage pack according to claim 1, wherein the control unit determines that an abnormality has occurred in any one of the temperature measurement systems including the temperature sensor, the multiple systems, and the control unit when a state in which the measurement value is determined to contain noise continues for a certain period of time.

7. The energy storage pack according to claim 1, further comprising a power storage module including a plurality of cells, and the temperature sensor is disposed in the power storage module.

8. The electricity storage pack according to claim 1, wherein the high frequency filter is a ferrite bead.