Power storage device and current interruption method

Abstract

To improve safety of a power storage device.SOLUTION: A power storage device 100 comprises a power storage device module 10, a voltage sensor 20, a current sensor 30, a pyro fuse 40, and a controller 50. The voltage sensor 20 detects a voltage value V of the power storage device module 10. The current sensor 30 detects a current value I flowing in the power storage device module 10. The pyro fuse 40 is connected in series with the power storage device module 10. In the controller 50, a voltage condition and a current condition are set. The voltage condition is predetermined on the basis of the voltage value V detected by the voltage sensor 20. The current condition is predetermined on the basis of the current value I detected by the current sensor 30. The controller 50 operates the pyro fuse 40 when both of the voltage condition and the current condition are satisfied.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an electricity storage device and a current interruption method. [Background technology]

[0002] Japanese Patent Application Laid-Open Publication No. 2022-133241 discloses a contactor for selectively connecting / disconnecting a battery. The contactor disclosed in this publication includes a subcircuit, a magnetic sensor, and a controller. The subcircuit includes a conductor portion connected in series, a switch, and a fuse. The magnetic sensor measures the current flowing through the conductor portion. The contactor further includes a detection means for detecting the actual opening / closing of the switch. The controller detects whether an overcurrent state has occurred. If the controller detects the overcurrent state, it opens the switch. The controller detects whether the main switch is effectively open. If the controller detects that the switch is still closed, it blows the fuse. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2022-133241 Summary of the Invention [Problem to be solved by the invention]

[0004] The present inventors wish to further improve the safety of power storage devices. [Means for solving the problem]

[0005] The energy storage device disclosed herein includes an energy storage device module, a voltage sensor, a current sensor, a pyro-fuse, and a controller. The energy storage device module includes a plurality of energy storage devices. The voltage sensor detects the voltage value of the energy storage device module. The current sensor detects the value of the current flowing through the energy storage device module. The pyro-fuse is connected in series with the energy storage device module. The controller activates the pyro-fuse. A voltage condition and a current condition are set in the controller. The voltage condition is determined in advance based on the voltage value detected by the voltage sensor. The current condition is determined in advance based on the current value detected by the current sensor. The controller activates the pyro-fuse when both the voltage condition and the current condition are satisfied. Such an energy storage device has improved safety. [Brief explanation of the drawings]

[0006] [Figure 1] FIG. 1 is a schematic diagram showing a power storage device 100. As shown in FIG. [Figure 2] FIG. 2 is a flowchart showing the processing executed by the controller 50. [Figure 3] FIG. 3 is a time chart showing the control of the operation of the pyrofuse 40 by the controller 50. In FIG. DETAILED DESCRIPTION OF THE INVENTION

[0007] An embodiment of the technology disclosed herein will be described below with reference to the drawings. The embodiment described here is, of course, not intended to limit the present invention. The drawings are schematic and do not necessarily reflect the actual product. Furthermore, the same reference numerals are appropriately used for components and parts that perform the same function, and redundant explanations will be omitted where appropriate.

[0008] <Electricity storage device 100> Fig. 1 is a schematic diagram showing an energy storage device 100. As shown in Fig. 1, the energy storage device 100 includes an energy storage device module 10, a voltage sensor 20, a current sensor 30, a pyro-fuse 40, and a controller 50. The energy storage device 100 is also called an energy storage device pack, and is an assembly that includes not only an energy storage device but also a configuration for controlling the energy storage device.

[0009] <Electricity storage device module 10> The power storage device module 10 includes a plurality of power storage devices 10a. The power storage device module 10 includes a positive electrode and a negative electrode. The power storage devices 10a are configured to be able to extract electrical energy. The power storage devices 10a store power supplied from a charger 83. The power storage devices 10a are connected to a load 81 via a connector 101. The power storage devices 10a supply power to the load 81.

[0010] The power storage device 10a includes a secondary battery that can be repeatedly charged and discharged by the movement of charge carriers between a pair of electrodes (positive and negative electrodes) via an electrolyte. The power storage device 10a includes, for example, a lithium ion secondary battery, a nickel-metal hydride battery, etc. In the power storage device module 10, the power storage devices 10a may be connected in series, in parallel, or in a combination of series and parallel connections. In this embodiment, a power storage device module 10 is used in which a plurality of power storage devices 10a are connected in series. There may be one or more power storage device modules 10.

[0011] The power storage device 100 is provided with connectors 101 to 103. The connector 101 is connected to a connection line 101a extending from the positive electrode of the power storage device module 10 and a connection line 101b extending from the negative electrode of the power storage device module 10. A connection line 102a extending from a connector 102 and a connection line 103a extending from a connector 103 are connected to the connection line 101a. The connection line 102a branches off from the connection line 101a. The connection line 103a branches off from the connection line 102a. A connection line 102b extending from the connector 102 and a connection line 103b extending from the connector 103 are connected to the connection line 101b. The connection lines 102b and 103b branch off from the connection line 101b. The connectors 101 to 103 are configured to be connectable to an external connection device 80. The power storage device 100 can be connected to the connection device 80 via at least one of the connectors 101 to 103.

[0012] Although not particularly limited, the connection device 80 may be, for example, a load 81, a DC / DC converter 82, a charger 83, or the like. In this embodiment, the power storage device 100 may be connected to the load 81 via a connector 101. Power is supplied to the load 81 from the power storage device module 10 of the power storage device 100. In this embodiment, the load 81 is a load of an electric vehicle, and may be constituted by an electric motor, an inverter, or the like of the vehicle. Without being limited to this form, the power storage device 100 may be applied to devices other than a power storage device mounted on an electric vehicle. The charger 83 is a device capable of supplying power to the power storage device module 10. The charger 83 may be a device that rapidly charges the power storage device module 10, or may be a device that normally charges the power storage device module 10.

[0013] A first contactor 60 and a second contactor 70 are provided between the power storage device module 10 and the connectors 101 to 103. The first contactor 60 and the second contactor 70 switch between connection and disconnection of the power storage device module 10 and the connection device 80. The first contactor 60 is provided on a connection line 101a extending from the positive electrode of the power storage device module 10 toward the connectors 101 to 103. In other words, the first contactor 60 is provided between the positive electrode of the power storage device module 10 and the connectors 101 to 103. The second contactor 70 is provided on a connection line 101b extending from the negative electrode of the power storage device module 10 to the connectors 101 to 103. In other words, the second contactor 70 is provided between the negative electrode of the power storage device module 10 and the connectors 101 to 103.

[0014] The first contactor 60 and the second contactor 70 are configured to be able to individually switch between an open state and a closed state. Although not particularly limited, electromechanical relays, semiconductor relays, etc. may be used as the first contactor 60 and the second contactor 70. In the energy storage apparatus 100, when both the first contactor 60 and the second contactor 70 are in the closed state, the energy storage device module 10 and the external connection device 80 are electrically connected. The switching between the open state and the closed state of the first contactor 60 and the second contactor 70 may be controlled by the controller 50.

[0015] The power storage device 100 is provided with a precharge circuit 65 that prevents an inrush current from flowing to the connected device 80 and the power storage device module 10. The precharge circuit 65 is connected in parallel to the first contactor 60. The precharge circuit 65 is a circuit in which a precharge resistor 66 and a precharge relay 67 are connected in series. The precharge circuit 65 prevents an inrush current from flowing when power is supplied from the power storage device 100 to the load 81, when power is supplied from the charger 83 to the power storage device 100, etc. Below, the opening and closing control of the first contactor 60, the second contactor 70, and the precharge relay 67 will be described using the start-up of the load 81 as an example.

[0016] For example, before the load 81 is started, the first contactor 60, the second contactor 70, and the pre-charge relay 67 are in an open state. When the load 81 is started, the second contactor 70 and the pre-charge relay 67 are switched to a closed state. This connects the load 81 to the power storage device module 10 via the pre-charge circuit 65. At this time, because the pre-charge resistor 66 is provided in the pre-charge circuit 65, power is supplied to the load 81 from the power storage device module 10 at a low current. Thereafter, with the potential of the load 81 increased, the first contactor 60 is switched to a closed state. Next, the pre-charge relay 67 is switched to an open state. This prevents a large current from flowing when the load 81 is started.

[0017] The voltage value and current value of the power storage device module 10 are detected by a voltage sensor 20 and a current sensor 30, respectively. The power storage apparatus 100 is provided with a pyro-fuse 40 that operates based on the voltage value and current value of the power storage device module 10.

[0018] <Voltage sensor 20> The voltage sensor 20 detects the voltage value of the power storage device module 10. The voltage sensor 20 may be capable of measuring the voltage of the power storage device module 10, or may be capable of measuring the voltage of one or more power storage devices 10a that constitute the power storage device module 10. In this embodiment, the voltage sensor 20 is configured to be able to measure the voltage of each of the power storage device modules 10 connected in series. The voltage sensor 20 is configured to be able to communicate with the controller 50. The voltage of the power storage device module 10 measured by the voltage sensor 20 is transmitted to the controller 50.

[0019] <Current Sensor 30> The current sensor 30 measures the charge / discharge current flowing through the power storage device module 10. In this embodiment, the current sensor 30 is provided between the power storage device module 10 and the first contactor 60. The location of the current sensor 30 is not particularly limited. The current sensor 30 is configured to be able to communicate with the controller 50. The charge / discharge current measured by the current sensor 30 is transmitted to the controller 50.

[0020] Pyro Fuse 40 The pyrofuse 40 is connected in series with the power storage device module 10. The pyrofuse 40 is a safety device provided in the power storage device 100. The pyrofuse 40 is an explosive-type current breaker. The pyrofuse 40 contains explosives, and cuts off the conductive path when the explosives are ignited. The pyrofuse 40 is provided in the conductive path connecting the power storage device module 10 and the connection device 80. The pyrofuse 40 is provided between a positive electrode side connection point 101a1 connecting the first contactor 60 and the precharge circuit 65, and a connection point 101a2 where the connection line 102a branches off.

[0021] The position where the pyrofuse 40 is provided is not particularly limited as long as it can interrupt the conductive path of the power storage device module 10. The pyrofuse 40 may be provided between the power storage device module 10 and the first contactor 60. The pyrofuse 40 may be provided on the connection line 101b extending from the negative electrode of the power storage device module 10 to the connectors 101 to 103. When a plurality of power storage device modules 10 are connected in series, the pyrofuse 40 may be provided between adjacent power storage device modules 10. The pyrofuse 40 is operated by the controller 50.

[0022] <Controller 50> The controller 50 activates the pyrofuse 40 in accordance with predetermined conditions. The controller 50 may be, for example, a computer such as an ECU (Electronic Control Unit) or a circuit board equipped with a microcomputer. The computer performs required functions in accordance with, for example, a predetermined program. Each function of the computer is processed by the computer's arithmetic unit (also called a processor, CPU (Central Processing Unit), or MPU (Micro-Processing Unit)), storage device (memory, hard disk, etc.), and software working together.

[0023] The controller 50 includes a communication unit 51, a voltage condition setting unit 52, a current condition setting unit 53, a determination unit 54, and an instruction unit 55. Each of the units 51 to 55 of the controller 50 may be realized by one or more processors, or may be incorporated into a circuit. The communication unit 51 of the controller 50 is configured to be able to communicate with the voltage sensor 20 and the current sensor 30.

[0024] Communication between the controller 50 and the voltage sensor 20 and the current sensor 30 can be achieved by transmitting and receiving signals. The format of communication between the controller 50 and the voltage sensor 20 and the current sensor 30 is not particularly limited. For example, the controller 50 can receive information (voltage value information and current value information) transmitted from the voltage sensor 20 and the current sensor 30 as a digital signal, an analog signal, a logic signal, a PWM (Pulse Width Modulation) signal, or a wireless signal. The controller 50 may receive the voltage value information and the current value information as different types of signals. For example, the controller 50 may receive the voltage value information as a digital signal and the current value information as an analog signal. The controller 50 may receive the voltage value information and the current value information as the same type of signal. For example, the controller 50 may receive the voltage value information and the current value information as digital signals.

[0025] When the power storage device 100 and the connection device 80 are connected and the power storage device 100 is started up, the opening and closing of the first contactor 60, the second contactor 70, and the pre-charge relay 67 can be controlled in the above-described order. The power storage device 100 and the connection device 80 are electrically connected, and charging and discharging of the power storage device 100 begins. When charging and discharging the power storage device 100, the controller 50 acquires, via the communication unit 51, the voltage value V detected by the voltage sensor 20 and the current value I detected by the current sensor 30.

[0026] In the controller 50, a voltage condition that is determined in advance based on a voltage value and a current condition that is determined in advance based on a current value are set. The voltage condition is set by the voltage condition setting unit 52. The current condition is set by the current condition setting unit 53. The controller 50 activates the pyro-fuse 40 when both the voltage condition and the current condition are satisfied. The number of voltage conditions and the number of current conditions are not limited to one. The voltage condition setting unit 52 may set one or more voltage conditions. The current condition setting unit 53 may set one or more current conditions. Different voltage conditions and current conditions may be set for discharging (e.g., when power is supplied from the power storage device module 10 to the load 81) and charging (e.g., when charging the power storage device module 10 from the charger 83).

[0027] An example of the processing executed by the controller 50 when the power storage device 100 is charged or discharged will be described below.

[0028] In this embodiment, the voltage condition during discharge is set as "the voltage value V of the power storage device module 10 is equal to or less than a predetermined threshold Vth (the lower limit threshold Vthl shown in FIG. 3)." Furthermore, the current condition is set as "the current value I of the power storage device module 10 is equal to or greater than a predetermined threshold Ith." Here, the threshold Ith is set to a positive value, and the absolute value of the current value I is compared with the threshold Ith. The determination unit 54 determines whether the absolute value of the current value I and the voltage value V each satisfy the conditions set based on the thresholds Vth and Ith. In this way, the current condition can be determined by comparing the absolute value of the measured value of the current value I with the threshold Ith, and the voltage condition can be determined by comparing the measured value of the voltage value V with the threshold Vth.

[0029] Furthermore, the voltage condition during charging is set as "the voltage value V of the power storage device module 10 must be equal to or greater than a predetermined threshold value Vth (the upper limit threshold value Vthu shown in FIG. 3)."

[0030] Although the direction of current flow differs during discharging and charging, the threshold value Ith may be the same. Therefore, unlike the voltage condition, the current condition may be set to be the same during discharging and charging. However, the current condition is not limited to this form and may be set based on a measured value of the current value I. For example, during discharging (current is a positive value), the current condition may be set to "the current value I is equal to or greater than a predetermined upper threshold value Ithu," and during charging (current is a negative value), the current condition may be set to "the current value I is equal to or less than a predetermined lower threshold value Ithl." Regardless of whether during discharging or charging, the current condition may be set to "the current value I is equal to or greater than a predetermined upper threshold value Ithu, or the current value I is equal to or less than a predetermined lower threshold value Ithl."

[0031] In this embodiment, the voltage sensor 20 is configured to detect the voltage value of each of the multiple power storage devices 10a. The voltage value V of each of the multiple power storage devices 10a is transmitted from the voltage sensor 20 to the controller 50. In the controller 50, the voltage condition is determined based on the voltage value of one of the multiple power storage devices 10a. Here, the determination unit 54 determines whether one of the multiple power storage devices 10a satisfies the voltage condition (whether each power storage device 10a is equal to or less than the threshold Vth). The voltage value V of each of the multiple power storage devices 10a may be different. When at least one of the multiple power storage devices 10a satisfies the voltage condition, the determination unit 54 determines that the voltage value V satisfies the voltage condition. Note that the determination of the voltage condition is not limited to being based on the voltage value V of one power storage device 10a. For example, when a power storage device module 10 is provided, the determination may be made based on the voltage value V of one of the power storage device modules 10. Alternatively, the voltage condition may be determined based on the voltage value V of all the power storage device modules 10 (so-called total voltage).

[0032] 2 is a flowchart showing the processing executed by controller 50. When charging / discharging of power storage device 100 starts and controller 50 acquires the voltage value from voltage sensor 20 and the current value from current sensor 30, control as to whether or not pyroelectric fuse 40 should be activated is started.

[0033] In step S10 (see FIG. 2), the determination unit 54 determines whether the voltage value V and the current value I each satisfy the determination conditions (voltage condition and current condition). If neither the voltage value V nor the current value I satisfies the voltage condition or the current condition (No), the pyro-fuse 40 does not operate, and charging and discharging of the power storage device module 10 continues. If either the voltage value V or the current value I satisfies the condition (Yes), the process proceeds to step S15 (see FIG. 2).

[0034] In step S15, it is determined which of the voltage value V and the current value I satisfies the condition. In step S15, if the current value I is equal to or greater than the threshold value Ith and satisfies the current condition, the process proceeds to step S20 (see FIG. 2). In step S20, it is determined whether the voltage value V satisfies the voltage condition. If the voltage value V is higher than the threshold value Vth and does not satisfy the voltage condition (No), the pyrofuse 40 does not activate, and charging and discharging of the power storage device module 10 continues. If the voltage value V is equal to or less than the threshold value Vth and satisfies the voltage condition (Yes), the controller 50 transmits a disconnection signal to the pyrofuse 40 from the instruction unit 55. The pyrofuse 40 is activated by the received disconnection signal and ruptures the conductive path (in this embodiment, the connection line 101a).

[0035] Furthermore, in step S15, if the voltage value V is equal to or less than the threshold value Vth and satisfies the voltage condition, the process proceeds to step S30 (see FIG. 2). In step S30, it is determined whether the current value I satisfies the current condition. If the current value I is lower than the threshold value Ith and does not satisfy the current condition (No), the pyrofuse 40 does not activate, and charging and discharging from the power storage device module 10 continues. If the current value I is equal to or greater than the threshold value Ith and satisfies the current condition (Yes), the controller 50 transmits a disconnection signal to the pyrofuse 40 from the instruction unit 55. The pyrofuse 40 is activated by the received disconnection signal and ruptures the conductive path (in this embodiment, the connection line 101a).

[0036] FIG. 3 is a time chart of the control of the operation of the pyro-fuse 40 by the controller 50. FIG. 3 shows control that is executed based on fluctuations in the voltage value V and the current value I when power is supplied from the power storage device 100 to the load 81 (when the power storage device 100 is discharging). The threshold value Ith is a set value of a current value at which an overcurrent is assumed to have flowed. The threshold value Ith can be set to a value higher (or higher) than the current value that can flow during normal use of the power storage device module 10. The threshold value Vth is a set value of a voltage value at which an overdischarge is assumed to have occurred. The threshold value Vth can be set within a range that can be taken during normal use of the power storage device module 10. A lower limit threshold Vthl and an upper limit threshold Vthu can be set as the threshold value Vth. The lower limit threshold Vthl and the upper limit threshold Vthu can be set according to the rated voltage and maximum charging voltage of the power storage device 10a, etc.

[0037] 3, the fluctuations in the current value I and the voltage value V when the pyrofuse 40 is activated, such as when a malfunction occurs in the power storage device 10a, are shown by solid lines, and the fluctuations in the current value I and the voltage value V when the pyrofuse 40 is not activated are shown by two-dot chain lines. Note that FIG. 3 merely shows one example of the fluctuations in the voltage value V and the current value I, and the voltage value V and the current value I do not necessarily fluctuate as shown in FIG. 3.

[0038] First, a process (shown by a solid line in FIG. 3) in which the controller 50 activates the pyro-fuse 40 when a malfunction occurs in the power storage device 10a or the like will be described.

[0039] After discharge starts (time t0), the determination process of step S10 in Fig. 2 begins. Current flows, and the power stored in the power storage device module 10 is supplied to the load 81. The current value I gradually increases, and the voltage value V begins to decrease. Since neither the current value I nor the voltage value V meets the conditions (current condition and voltage condition) (determination of "No" in step S10), the pyroelectric fuse 40 does not activate.

[0040] In this embodiment, the current value I reaches the threshold value Ith at time t1. After time t1, the determination in step S10 is "Yes." Here, the determination in step S15 is that the "current condition" is satisfied. Because the voltage value V is higher than the threshold value Vth (higher than the lower threshold value Vthl and lower than the upper threshold value Vthu), the determination in step S20 is "No," and the pyro-fuse 40 does not activate.

[0041] At time t2, the current value I remains equal to or greater than the threshold value Ith. At time t2, the voltage value V drops further and reaches the threshold value Vth (in this embodiment, the lower limit threshold value Vthl). After time t2, the determination in step S20 is "Yes," and the pyroelectric fuse 40 is activated.

[0042] In this embodiment, there is a delay time td from when the determination in step S20 is "Yes" until the controller 50 activates the pyrofuse 40. Therefore, the pyrofuse 40 activates at time t3, which is the time when the delay time td has elapsed since the determination in step S20 was "Yes" at time t2.

[0043] Next, a process in which the power storage device module 10 operates normally and the controller 50 does not activate the pyrofuse 40 (the form shown by the two-dot chain line in FIG. 3) will be described.

[0044] 3, when no abnormality occurs in the power storage device module 10, the current value I remains lower than the threshold value Ith and the voltage value V remains higher than the lower limit threshold value Vthl (the voltage value V remains higher than the lower limit threshold value Vthl and lower than the upper limit threshold value Vthu). In this case, the determination in step S10 is "No," and the pyro-fuse 40 does not activate.

[0045] Controller 50 may detect noise in the signals (voltage value V or current value I) transmitted from voltage sensor 20 and current sensor 30. Due to the signal noise, it may be determined that either one of voltage value V or current value I temporarily satisfies the condition. In this case, step S10 returns "Yes." If step S15 determines that current value I is equal to or greater than threshold value Ith due to noise, the process proceeds to step S20. Because voltage value V is higher than lower threshold value Vthl and lower than upper threshold value Vthu, the process proceeds to step S20. If step S15 determines that voltage value V is equal to or greater than lower threshold value Vthl (or higher than upper threshold value Vthu) due to noise, the process proceeds to step S30. Because current value I is lower than threshold value Ith, the process returns "No" and pyrofuse 40 does not activate.

[0046] In the above-described embodiment, the power storage apparatus 100 includes a power storage device module 10, a voltage sensor 20, a current sensor 30, a pyro-fuse 40, and a controller 50. The power storage device module 10 includes a plurality of power storage devices 10a. The voltage sensor 20 detects a voltage value V of the power storage device module 10. The current sensor 30 detects a current value I flowing through the power storage device module 10. The pyro-fuse 40 is connected in series with the power storage device module 10. The controller 50 activates the pyro-fuse 40. A voltage condition and a current condition are set in the controller 50. The voltage condition is determined in advance based on the voltage value V detected by the voltage sensor 20. The current condition is determined in advance based on the current value I detected by the current sensor 30. The controller 50 activates the pyro-fuse 40 when both the voltage condition and the current condition are satisfied. In this energy storage device 100, the conditions for activating the pyrofuse 40 are determined based on both the voltage condition and the current condition. As a result, even if the voltage value V and the current value I are erroneously detected due to noise or the like, the pyrofuse 40 will not activate. This makes it possible to more accurately determine whether an abnormality has occurred in the energy storage device module 10. As a result, the risk of the pyrofuse 40 activating due to a malfunction is reduced. By appropriately controlling the timing at which the pyrofuse 40 activates, the risk of the energy storage device module 10 being shut down due to a malfunction is reduced. As a result, the safety of the energy storage device 10 is improved.

[0047] In the above-described embodiment, the voltage condition is set to "the voltage value of the power storage device module 10 must be equal to or less than a predetermined threshold Vth (in this embodiment, a lower limit threshold Vthl)" during discharge. This allows an abnormality that may occur when the power storage device module 10 is over-discharged to be detected, and the conduction path can be cut off by the pyro-fuse 40. As a result, the safety of the power storage apparatus 100 can be improved.

[0048] In the above-described embodiment, the voltage condition is set to "the voltage value of the power storage device module 10 must be equal to or greater than a predetermined threshold value Vth (in this embodiment, an upper limit threshold value Vthu)" during charging. This allows an abnormality that may occur when the power storage device module 10 is overcharged to be detected, and the conduction path can be cut off by the pyro-fuse 40. As a result, the safety of the power storage apparatus 100 can be improved.

[0049] In the above-described embodiment, the current condition is set to "the current value I of the power storage device module 10 is equal to or greater than a predetermined threshold value Ith." This makes it possible to detect possible abnormalities in the power storage apparatus 100 under common current conditions both during charging and discharging. Note that if an overcurrent flows between the power storage device module 10 and the connected device 80, overcharging may occur during charging, and overdischarging may occur during discharging. In this embodiment, the current condition is set to "the absolute value of the current value I of the power storage device module 10 is equal to or greater than a predetermined threshold value Ith," making it easier to accurately detect abnormalities during charging and discharging.

[0050] In the above-described embodiment, the voltage condition is determined based on the voltage value V of one of the power storage devices 10a among the multiple power storage devices 10a. This allows the pyro-fuse 40 to be quickly cut off even if an abnormality occurs in any of the power storage devices 10a included in the power storage device module 10. This can improve the safety of the power storage apparatus 100.

[0051] The voltage and current conditions set in the controller 50 for activating the pyrofuse 40 are not limited to those described above. Other conditions may be added to the voltage and current conditions, or they may be changed to other conditions.

[0052] The voltage condition may be set to "the voltage value V is outside the detection range." "Outside the detection range" may mean, for example, that the voltage value exceeds an upper detection limit in at least one of the voltage sensor 20 and the controller 50. The upper detection limit may depend on the device characteristics of the voltage sensor 20 and the controller 50 used. The upper detection limit of the voltage condition may be a value higher than the upper limit threshold Vthu described above. By employing such a voltage condition, the pyrofuse 40 is more likely to operate appropriately even when the voltage value V cannot be measured normally due to the occurrence of an abnormality.

[0053] The current condition may be set to "current value I is outside the detection range." "Outside the detection range" may mean, for example, that the current value exceeds an upper detection limit in at least one of the current sensor 30 and the controller 50. The upper detection limit may depend on the device characteristics of the current sensor 30 and the controller 50 used. The upper detection limit of the current condition may be a value higher than the threshold value Ith described above. By employing such a current condition, the pyro-fuse 40 is more likely to operate appropriately even when the current value I cannot be measured normally due to an abnormality.

[0054] The voltage sensor 20 is not limited to a configuration that detects a voltage value V and transmits the detected voltage value V as a signal to the controller 50. The voltage sensor 20 may be capable of detecting at least one of overcharging and overdischarging of the power storage device module 10 or the power storage device 10a. For example, the voltage sensor 20 may be configured to detect a voltage value V. A threshold value (e.g., the threshold value Vth) for overcharging and overdischarging may be set in the voltage sensor 20. As described above, the voltage sensor 20 may be configured to detect the overcharging and overdischarging events that were detected by the controller 50 in the above-described embodiment. Here, the voltage sensor 20 may be configured to notify the controller 50 of the detection of at least one of the events when it detects at least one of the events. The voltage condition may be set to "the voltage sensor 20 notifies the controller 50 of the detection of at least one of overcharging and overdischarging." By detecting overcurrent and overcharging by the voltage sensor 20, the accuracy of abnormality detection may be improved.

[0055] Similarly, the current sensor 30 is not limited to a configuration that detects the current value I and transmits it as a signal to the controller 50. The current sensor 30 may be capable of detecting an overcurrent in the power storage device module 10. For example, the current sensor 30 may be configured to detect the current value I. A threshold value for an overcurrent (e.g., the above-mentioned threshold value Ith) may be set in the current sensor 30. In this way, the current sensor 30 may be configured to detect the overcurrent event that was detected by the controller 50 in the above-mentioned embodiment. Here, the current sensor 30 may be configured to notify the controller 50 of the detection of an overcurrent when it detects an overcurrent. The current condition may be set to "notification of the detection of an overcurrent from the current sensor 30." By detecting an overcurrent also by the current sensor 30, the accuracy of abnormality detection may be improved.

[0056] Furthermore, the controller 50 may be set with a voltage condition that "communication from the voltage sensor 20 to the controller 50 is interrupted." Similarly, the controller 50 may be set with a current condition that "communication from the current sensor 30 to the controller 50 is interrupted." These events may be determined when the controller 50 does not receive signals from the sensors (voltage sensor 20, current sensor 30) even though the power storage device 100 is activated. By setting such conditions, it becomes easier to detect possible malfunctions in the power storage device 100.

[0057] As described above, a plurality of voltage conditions and a plurality of current conditions may be set in the energy storage device 100. Setting a plurality of conditions makes it easier to activate the pyroelectric fuse 40 in response to various malfunctions that may occur in the energy storage device 100. As a result, the safety of the energy storage device 100 can be improved.

[0058] The technology disclosed herein has been described in various ways. Unless otherwise specified, the embodiments and the like described herein do not limit the present invention. Furthermore, the technology disclosed herein can be modified in various ways, and as long as no particular problems arise, each component and each process described herein can be omitted or combined as appropriate. Furthermore, this specification includes the disclosures described in the following sections.

[0059] Section 1: a power storage device module including a plurality of power storage devices; a voltage sensor that detects a voltage value of the power storage device module; a current sensor that detects a value of a current flowing through the power storage device module; a pyro-fuse connected in series with the power storage device module; a controller that activates the pyrofuse; Equipped with The controller a voltage condition that is determined in advance based on a voltage value detected by the voltage sensor; a current condition that is determined in advance based on a current value detected by the current sensor; is set, The power storage device activates the pyro-fuse when both the voltage condition and the current condition are satisfied.

[0060] Section 2: Item 2. The power storage device according to item 1, wherein the voltage condition is set such that the voltage value of the power storage device module during discharge is equal to or less than a predetermined threshold value.

[0061] Section 3: 3. The power storage device according to item 1 or 2, wherein the voltage condition is set such that the voltage value of the power storage device module during charging is equal to or higher than a predetermined threshold value.

[0062] Section 4: 4. The power storage apparatus according to any one of items 1 to 3, wherein the current condition is set such that the current value of the power storage device module is equal to or greater than a predetermined threshold value.

[0063] Section 5: 5. The power storage device according to any one of items 1 to 4, wherein the voltage condition is determined based on a voltage value of one of the plurality of power storage devices.

[0064] Item 6: 6. The power storage device according to any one of items 1 to 5, wherein the voltage condition is set to the voltage value being outside a detection range.

[0065] Section 7: 7. The power storage device according to any one of items 1 to 6, wherein the current condition is set to be that the current value is outside a detection range.

[0066] Section 8: the voltage sensor is configured to be capable of detecting at least one of an overcharge and an overdischarge event, and, when detecting at least one of the events, to notify the controller of the detection of at least one of the events; 8. The power storage device according to any one of items 1 to 7, wherein the voltage condition is set to be that the voltage sensor has notified the detection of at least one of the events.

[0067] Section 9: the current sensor is configured to be able to notify the controller of the detection of an overcurrent when the current sensor detects an overcurrent; 9. The power storage device according to any one of items 1 to 8, wherein the current condition is set to be that the current sensor has notified the user of the detection of the overcurrent.

[0068] Section 10: A current interruption method for interrupting a current flowing through an electricity storage device module including a plurality of electricity storage devices, comprising: Detecting a voltage value of the power storage device module; Detecting a current value flowing through the power storage device module; Activating a pyrofuse when a predetermined condition is met; Including, the pyrofuse is connected in series with the power storage device module; The predetermined conditions are: a voltage condition determined based on the voltage value; Current conditions determined based on the current value is set, A current interruption method, which activates the pyrofuse when both the voltage condition and the current condition are satisfied. [Explanation of symbols]

[0069] 10. Energy storage device module 10a Energy storage device 20 Voltage Sensor 30 Current Sensor 40 Pyro Fuse 50 Controllers 51 Communications Department 52 Voltage condition setting section 53 Current condition setting section 54 Judgment section 55 Instruction section 65 Precharge circuit 66 Precharge resistor 67 Precharge relay 80 connected devices 81 Load 82 DC / DC converter 83 Charger 100 Electricity storage device 101~103 Connectors 101a~103a, 101b~103b connecting lines 101a1,101a2 connection point

Claims

1. a power storage device module including a plurality of power storage devices; a voltage sensor that detects a voltage value of the power storage device module; a current sensor that detects a value of a current flowing through the power storage device module; a pyro-fuse connected in series with the power storage device module; a controller that activates the pyrofuse; Equipped with The controller a voltage condition that is determined in advance based on a voltage value detected by the voltage sensor; a current condition that is determined in advance based on a current value detected by the current sensor; is set, The power storage device activates the pyro-fuse when both the voltage condition and the current condition are satisfied.

2. The power storage apparatus according to claim 1 , wherein the voltage condition is set such that the voltage value of the power storage device module during discharge is equal to or lower than a predetermined threshold value.

3. The power storage apparatus according to claim 1 , wherein the voltage condition is set such that the voltage value of the power storage device module during charging is equal to or greater than a predetermined threshold value.

4. 4. The power storage device according to claim 1, wherein the current condition is set such that the current value of the power storage device module is equal to or greater than a predetermined threshold value.

5. 4. The power storage device according to claim 1, wherein the voltage condition is determined based on a voltage value of one of the plurality of power storage devices.

6. 4. The power storage device according to claim 1, wherein the voltage condition is set to the voltage value being outside a detection range.

7. 4. The power storage device according to claim 1, wherein the current condition is set to be that the current value is outside a detection range.

8. the voltage sensor is configured to be capable of detecting at least one of an overcharge and an overdischarge event, and, when detecting at least one of the events, to notify the controller of the detection of at least one of the events; 4. The power storage device according to claim 1, wherein the voltage condition is set to be that the voltage sensor has notified the user of the detection of at least one of the events.

9. the current sensor is configured to be able to notify the controller of the detection of an overcurrent when the current sensor detects an overcurrent; 4. The power storage device according to claim 1, wherein the current condition is set to be that the current sensor has notified the user of the detection of the overcurrent.

10. A current interruption method for interrupting a current flowing through an electricity storage device module including a plurality of electricity storage devices, comprising: Detecting a voltage value of the power storage device module; Detecting a current value flowing through the power storage device module; Activating a pyrofuse when a predetermined condition is met; Including, the pyrofuse is connected in series with the power storage device module; The predetermined conditions include: a voltage condition determined based on the voltage value; Current conditions determined based on the current value is set, A current interruption method, which activates the pyrofuse when both the voltage condition and the current condition are satisfied.

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