Cell voltage detection device

Abstract

To provide a cell voltage detector with which, while securing a desired general versatility, it is possible to prevent occurrence of abnormalities such as short-circuiting and overvoltages.SOLUTION: A cell voltage detector 10 comprises: a circuit board 9 which is provided with a plurality of conductors 25 connected to a plurality of unit cells 11 constituting a power storage module 3; and a processing unit 7 that is connected to the circuit board 9 and detects the voltage of each of the plurality of unit cells 11. The circuit board 9 includes: at least one first switch unit 27a which is provided to at least one prescribed conductor 25 and is switched to be electrically continuous and electrically non-continuous; and at least one second switch unit 27b which is switched to be electrically continuous and electrically non-continuous between the first switch unit 27a and the processing unit 7 in the conductor 25 where the first switch unit 27a is provided, and between at least one prescribed conductor 25 selected according to the prescribed voltage of the processing unit 7 and itself.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a cell voltage detection device. [Background technology]

[0002] In recent years, efforts to realize a low-carbon or carbon-free society have become more active, and research and development into electrification technologies has been conducted to reduce CO2 emissions and improve energy efficiency in vehicles. In this electrification technology, if the batteries used are, for example, lithium-ion batteries, the voltage of each cell constituting the assembled battery is monitored to control the battery capacity. In this case, a detection line is connected to a control device to detect the voltage of each single cell. It is known to provide a jumper resistor to disconnect the assembly detection line (see, for example, Patent Document 1). In this device, a common board is used regardless of the number of cells in the battery pack, so jumper resistors are set to non-mounted according to the number of cells that the board can accommodate. As a result, even if the number of cells in the battery pack is greater than the number that the board can accommodate due to, for example, incorrect battery connection, the detection line is disconnected to prevent short-circuiting of the individual cells on the board. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2018 / 235457 Summary of the Invention [Problem to be solved by the invention]

[0004] In the technology related to electrification, for example, when the number of cells in the assembled battery is smaller than the number of cells that can be accommodated on the circuit board, it is necessary to be able to properly detect the voltage of each single cell. In addition, even when the number of cells in the assembled battery is greater than the number of cells that can be accommodated on the circuit board due to incorrect connection or the like, it is also an issue to prevent abnormalities such as short circuits and overvoltages on the circuit board.

[0005] In order to solve the above-mentioned problems, the present application aims to prevent the occurrence of abnormalities such as short circuits and overvoltages while ensuring the desired versatility of a cell voltage detection device, thereby contributing to improving energy efficiency. [Means for solving the problem]

[0006] In order to solve the above problems and achieve the above object, the present invention employs the following aspects. (1): A cell voltage detection device according to one aspect of the present invention (e.g., cell voltage detection device 10 in the embodiments) includes an electric circuit (e.g., circuit board 9 in the embodiments) including a plurality of conductors (e.g., conductors 25 in the embodiments) connected to a plurality of unit cells (e.g., unit cell 11 in the embodiments) that constitute a storage module (e.g., storage module 3 in the embodiments), and a processing unit (e.g., processing unit 7 in the embodiments) that is connected to the electric circuit and detects the voltage of each of the unit cells. The electric circuit includes at least one first switching unit (e.g., first switching unit 27a in the embodiments) that is provided on at least one predetermined conductor and that switches between conduction and non-conduction, and at least one second switching unit (e.g., second switching unit 27b in the embodiments) that switches between conduction and non-conduction between the first switching unit and the processing unit on the conductor on which the first switching unit is provided and at least one predetermined conductor selected in accordance with a predetermined withstand voltage of the processing unit.

[0007] (2): In the cell voltage detection device described in (1) above, the processing unit includes a first terminal (e.g., the first connection terminal 17 (C1) in the embodiment) connected to the first conductor (e.g., the first conductor 25 (L1) in the embodiment) on the low potential side, a second terminal (e.g., the second connection terminal 17 (C2) in the embodiment) connected to the second conductor (e.g., the n-th conductor 25 (Ln) in the embodiment) on the high potential side, and N different conductors (e.g., the second conductor 25 (L2), ..., the (n-1)-th conductor 25 (Ln-1) in the embodiment) between the first terminal and the second terminal in potential order, where N is an arbitrary natural number. The electrical circuit body may include N terminals that are not involved in detection (e.g., connection terminal 17 (NC) in the embodiment), and the electrical circuit body may include (NM) switching modules (e.g., second switching module 29 in the embodiment) when the number of unit cells corresponding to the specified withstand voltage is M, where M is any natural number less than or equal to N, and the switching module may include a conductor switching unit (e.g., fourth switching unit 29a in the embodiment) that switches between conduction and non-conduction of the conductor on the lower potential side of two adjacent conductors in potential order, and an inter-conductor switching unit (e.g., fifth switching unit 29b in the embodiment) that switches between conduction and non-conduction between the two conductors.

[0008] (3): In the cell voltage detection device described in (1) or (2) above, the electrical circuit body may include a third switching unit (e.g., third switching unit 27c in the embodiment) that is provided on the conductor adjacent to the conductor on the highest potential side connected to the second switching unit and that switches between conductive and non-conductive states. [Effects of the Invention]

[0009] According to the above (1), by providing the first switching unit and the second switching unit that can be switched between conductive and non-conductive states, it is possible to properly accommodate the number of voltage detection channels corresponding to the number of unit cells that the processing unit can accommodate, without having to change the wiring pattern of the electric circuit body. For example, even if an energy storage module having a number of unit cells greater than the number of channels of the processing unit is erroneously connected, the first switching unit and the second switching unit can prevent the occurrence of abnormalities such as short circuits and overvoltages. It is possible to ensure versatility that can properly accommodate multiple processing units with different numbers of channels, and to prevent abnormalities from occurring even when an energy storage module that is not properly compatible with the processing unit is erroneously connected.

[0010] In the case of (2) above, versatility can be improved by setting the number of switching modules, which are made up of conductor switching units and inter-conductor switching units that switch between conductive and non-conductive states, according to the number N of terminals that are not involved in voltage detection by the processing unit and the number M of unit cells that corresponds to the predetermined withstand voltage of the processing unit. By providing (NM) switching modules, it is possible to properly correspond to the number of voltage detection channels of the processing unit, and to prevent abnormalities such as short circuits and overvoltages even when a storage module that is not properly compatible with the processing unit is incorrectly connected.

[0011] According to (3) above, by providing a third switching unit that can switch between conductive and non-conductive states, it is possible to ensure versatility to properly correspond to a plurality of processing units with different numbers of channels, and it is possible to prevent abnormalities even when a storage module that does not properly correspond to the processing unit is incorrectly connected. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is a configuration diagram of a power storage system including a cell voltage detection device according to an embodiment of the present invention; [Figure 2] FIG. 2 is a diagram showing a first example of a combination of a circuit board and a processing unit in the cell voltage detection device according to the embodiment of the present invention. [Figure 3] FIG. 10 is a diagram showing a second example of a combination of a circuit board and a processing unit in the cell voltage detection device according to the embodiment of the present invention. [Figure 4] FIG. 10 is a diagram showing a third example of a combination of a circuit board and a processing unit in the cell voltage detection device according to the embodiment of the present invention. [Figure 5] FIG. 10 is a diagram showing a fourth example of a combination of a circuit board and a processing unit in a cell voltage detection device according to an embodiment of the present invention. [Figure 6] FIG. 10 is a diagram showing a fifth example of a combination of a circuit board and a processing unit in a cell voltage detection device according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0013] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A cell voltage detection device according to an embodiment of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a configuration diagram of a power storage system 1 including a cell voltage detection device 10 according to an embodiment. The power storage system 1 according to this embodiment is mounted on, for example, various types of mobile bodies, such as electric vehicles, hybrid vehicles, and fuel cell vehicles, mobile work machines, and other robots. 1, the power storage system 1 includes, for example, a power storage module 3, a wire harness 5, a processing unit 7, and a circuit board 9. For example, the processing unit 7 and the circuit board 9 configure a cell voltage detection device 10.

[0014] The energy storage module 3 includes a plurality of unit cells 11 connected in series. The plurality of unit cells 11 are, for example, k unit cells 11, where k is a predetermined number. The voltages of the plurality of unit cells 11 are, for example, voltages V1, ..., Vk, in sequence. The energy storage module 3 includes a plurality of terminals 13 connected to a wire harness 5, which will be described later. The plurality of terminals 13 are, for example, n terminals S1, ..., Sn, which are a predetermined number n that is set in common among the wire harness 5, the processing unit 7, and the circuit board 9 in an appropriate combination, which will be described later. The predetermined number n is set to be equal to or greater than (k+1) based on a predetermined number k, thereby allowing the existence of terminals 13 that are not connected to any of the unit cells 11, in accordance with the sharing of the wire harness 5 and the circuit board 9 among a plurality of energy storage modules 3 having different numbers of unit cells 11.

[0015] For example, the energy storage module 3 is made up of a plurality of cell modules connected in series. Each cell module is made up of a number of unit cells 11 obtained by dividing a plurality of unit cells 11 and a number of terminals 13 obtained by dividing a plurality of terminals 13.

[0016] The wire harness 5 includes multiple pairs of terminals 15. The multiple pairs of terminals 15 are, for example, n pairs of terminals 15, where n is a predetermined number. The wire harness 5 connects the multiple terminals 13 of the power storage module 3 to multiple terminals 21 of the circuit board 9, which will be described later, in a predetermined order. The wire harness 5 associates, for example, the predetermined order from the low potential side to the high potential side of the multiple terminals 13 of the power storage module 3 with the predetermined order from the low potential side to the high potential side of the multiple terminals 21 of the circuit board 9. For example, the wire harness 5 is made up of a plurality of harnesses corresponding to the plurality of cell modules of the power storage module 3. Each harness is made up of a plurality of pairs of terminals 15 corresponding to the number of terminals 13 of each cell module.

[0017] The processing unit 7 is a software functional unit that functions when a processor such as a CPU (Central Processing Unit) executes a predetermined program. The software functional unit is an ECU that includes a processor such as a CPU, a ROM (Read Only Memory) that stores programs, a RAM (Random Access Memory) that temporarily stores data, and electronic circuits such as a timer. At least a part of the processing unit 7 may be an integrated circuit such as an LSI (Large Scale Integration).

[0018] The processing unit 7 is mounted on a circuit board 9, which will be described later. The processing unit 9 includes, for example, a plurality of connection terminals 17 and a plurality of detection terminals 19. The plurality of connection terminals 17 are connected to wiring on the circuit board 9. The plurality of connection terminals 17 are, for example, n connection terminals P1, ..., Pn, where n is a predetermined number. The plurality of detection terminals 19 are terminals for detecting the voltage of each unit cell 11 of the energy storage module 3, and are connected to the plurality of connection terminals 17. The plurality of detection terminals 19 are, for example, m detection terminals R1, ..., Rm, where m is a predetermined number. By setting the predetermined number m to be equal to or less than the predetermined number n, the presence of connection terminals 17 that are not connected to any detection terminals 19 is permitted, due to so-called pin compatibility, in order to accommodate sharing of the circuit board 9 among a plurality of processing units 7 having different numbers of detection terminals 19. The processing unit 7 detects the voltage between each of the two detection terminals 19 connected to both ends of each unit cell 11 of the power storage module 3.

[0019] The circuit board 9 is any of various electric circuit bodies, such as a rigid board, a flexible board, a rigid-flexible board, or a stretchable board. The circuit board 9 is not limited to a rigid plate-like substrate, and may include, for example, any of various thin-film-like substrates that have at least one of flexibility and stretchability. The circuit board 9 is, for example, an electronic component in which wiring, electronic components, and the like are directly disposed on any of various substrates.

[0020] The circuit board 9 includes a plurality of terminals 21, a plurality of conductive wires 25 forming wiring 23, at least one first switching portion 27a, and at least one second switching portion 27b. The plurality of terminals 21 are connected to the plurality of terminals 13 of the power storage module 3 via the wire harness 5. The plurality of terminals 21 are, for example, n terminals T1, ..., Tn, where n is a predetermined number. The plurality of conductors 25 are provided between the plurality of terminals 21 and the plurality of connection terminals 17 of the processing unit 7. The plurality of conductors 25 are, for example, n conductors L1, ..., Ln, where n is a predetermined number. The plurality of conductors 25 connect the plurality of terminals 21 and the plurality of connection terminals 17 of the processing unit 7 in a predetermined order. The plurality of conductors 25 correspond, for example, to a predetermined order from the low potential side to the high potential side of the plurality of terminals 21 and a predetermined order from the low potential side to the high potential side of the plurality of connection terminals 17 of the processing unit 7.

[0021] At least one first switching unit 27a is provided on at least one predetermined conductor 25 selected from the plurality of conductors 25 according to the internal configuration of the processing unit 7. The first switching unit 27a switches the conductor 25 between conductive and non-conductive states, for example, by switching between mounted and unmounted so-called jumper resistors or by switching between open and closed states using a switch.

[0022] At least one second switching unit 27b is provided between the first switching unit 27a and the processing unit 7 in the conductor 25 on which the first switching unit 27a is provided, and at least one predetermined conductor 25 selected according to a predetermined withstand voltage of the processing unit 7. The second switching unit 27b switches between conduction and non-conduction between the predetermined plurality of conductors 25, for example, by switching between mounting and non-mounting a so-called jumper resistor or by switching between opening and closing using a switch.

[0023] The switching between conductive (ON) and non-conductive (OFF) of each of the first switching unit 27a and the second switching unit 27b is set according to differences in the internal configuration, such as the connection state between the multiple connection terminals 17 and the multiple detection terminals 19 in the processing unit 7.

[0024] In the energy storage system 1, when the energy storage module 3, wire harness 5, processing unit 7, and circuit board 9 are connected in a normal, appropriate state, the number of voltage detection channels in the processing unit 7 (i.e., the number of channels capable of detecting the cell voltage of each unit cell 11 individually) is set to be equal to or greater than the number of the unit cells 11 constituting the energy storage module 3. For example, the number (m-1) of voltage detection channels corresponding to m detection terminals 19 based on a predetermined number m in the processing unit 7 is set to be equal to or greater than the number (k) of unit cells 11 based on a predetermined number k in the energy storage module 3.

[0025] Fig. 2 is a diagram showing a first example of a combination of a circuit board 9 (9a) and a processing unit 7 (7a) in the cell voltage detection device 10 of the embodiment. Fig. 3 is a diagram showing a second example of a combination of a circuit board 9 (9b) and a processing unit 7 (7b) in the cell voltage detection device 10 of the embodiment. The first embodiment shown in Figure 2 shows the configuration of the circuit board 9 (9a) when, for example, the predetermined number m in the processing unit 7 (7a) is less than the predetermined number n, and therefore there is a connection terminal 17 (NC) that is not connected to any detection terminal 19 and is not involved in voltage detection by the processing unit 7 (7a). The second embodiment shown in Figure 3 shows the configuration of the circuit board 9 (9b) when, for example, the predetermined number m in the processing unit 7 (7b) is the same as the predetermined number n, and all the connection terminals 17 (C1, C2, C3) are connected to the detection terminals 19 and thereby participate in voltage detection.

[0026] As shown in Fig. 2, the circuit board 9 (9a) of the first embodiment includes a first conducting wire 25 (L1), a second conducting wire 25 (L2), and a third conducting wire 25 (L3) arranged in this order from the low potential side to the high potential side. The first conducting wire 25 (L1) is connected to the first terminal 21 (T1) and the first connection terminal 17 (C1) on the low potential side. The second conducting wire 25 (L2) is connected to the second terminal 21 (T2) and the connection terminal 17 (NC) between the low potential side and the high potential side. The third conducting wire 25 (L3) is connected to the third terminal 21 (T3) and the second connection terminal 17 (C2) on the high potential side. The circuit board 9 (9a) of the first embodiment includes, for example, a first switching unit 27a that is set to non-conductive (OFF) in the second conducting wire 25 (L2), and a second switching unit 27b that is set to conductive (ON) between the second conducting wire 25 (L2) and the third conducting wire 25 (L3).

[0027] In the first embodiment, the first switching unit 27a is set to non-conductive (OFF), thereby preventing the occurrence of a short circuit due to the second switching unit 27b being set to conductive (ON), even when an incompatible power storage module 3 is erroneously connected to the processing unit 7 (7a). For example, the power storage module 3 shown in Fig. 2 includes k unit cells 11 with a predetermined number k that is greater than the number (m-1) of channels with a predetermined number m in the processing unit 7 (7a), and is in a state of being erroneously connected to the circuit board 9 (9a).

[0028] By being set to conductive (ON), the second switching unit 27b in the first embodiment prevents an excessive number of capacitors from being provided between adjacent conductors 25 in order of potential, even when a voltage smoothing capacitor is required between the two detection terminals 19 in the processing unit 7 (7a). For example, in the circuit board 9 (9a) shown in Fig. 2, the voltage (V1+V2) between the two detection terminals 19 due to the two unit cells 11 is smoothed only by the capacitor provided between the first conductor 25 (L1) and the second conductor 25 (L2) (i.e., no capacitor is required between the second conductor 25 (L2) and the third conductor 25 (L3)).

[0029] As shown in Fig. 3, the circuit board 9 (9b) of the second embodiment includes a first conducting wire 25 (L1), a second conducting wire 25 (L2), and a third conducting wire 25 (L3), similar to the circuit board 9 (9a) of the first embodiment. The first conducting wire 25 (L1) is connected to the first terminal 21 (T1) and the first connection terminal 17 (C1) on the low potential side. The second conducting wire 25 (L2) is connected to the second terminal 21 (T2) and the second connection terminal 17 (C2) between the low potential side and the high potential side. The third conducting wire 25 (L3) is connected to the third terminal 21 (T3) and the third connection terminal 17 (C3) on the high potential side. The circuit board 9 (9b) of the second embodiment has, for example, a first switching unit 27a that is set to conductive (ON) with the second conducting wire 25 (L2), and a second switching unit 27b that is set to non-conductive (OFF) between the second conducting wire 25 (L2) and the third conducting wire 25 (L3).

[0030] When a corresponding storage module 3 is connected to the processing unit 7 (7b), the first switching unit 27a and the second switching unit 27b of the second embodiment prevent short circuits between adjacent conductors 25 in order of potential, and properly generate voltages of the unit cells 11 between adjacent detection terminals 19 in order of potential. For example, the storage module 3 shown in Fig. 3 includes k unit cells 11 with a predetermined number k that is the same as the number of channels (m-1) with a predetermined number m in the processing unit 7, and is properly connected to the circuit board 9 (9b).

[0031] Fig. 4 is a diagram showing a third example of a combination of the circuit board 9 (9c) and the processing unit 7 (7c) in the cell voltage detecting device 10 of the embodiment. Fig. 5 is a diagram showing a fourth example of a combination of the circuit board 9 (9d) and the processing unit 7 (7d) in the cell voltage detecting device 10 of the embodiment. The third embodiment shown in Figure 4 shows the configuration of the circuit board 9 (9c) in the case where, for example, the predetermined number m in the processing unit 7 (7c) is less than the predetermined number n, and therefore there is a connection terminal 17 (NC) that is not connected to any detection terminal 19 and is not involved in voltage detection by the processing unit 7 (7c). The fourth embodiment shown in Figure 5 shows the configuration of the circuit board 9 (9d) when, for example, the predetermined number m in the processing unit 7 (7d) is the same as the predetermined number n, and all the connection terminals 17 (C1, C2, C3, C4) are connected to the detection terminals 19 and thereby participate in voltage detection.

[0032] As shown in Fig. 4, the circuit board 9 (9c) of the third embodiment includes a first conductive wire 25 (L1), a second conductive wire 25 (L2), a third conductive wire 25 (L3), and a fourth conductive wire 25 (L4) arranged in this order from the low potential side to the high potential side. The first conductive wire 25 (L1) is connected to the first terminal 21 (T1) and the first connection terminal 17 (C1) on the low potential side. The second conductive wire 25 (L2) and the third conductive wire 25 (L3) are connected to the second terminal 21 (T2) and the third terminal 21 (T3), respectively, and the connection terminal 17 (NC) between the low potential side and the high potential side. The fourth conductive wire 25 (L4) is connected to the fourth terminal 21 (T4) and the second connection terminal 17 (C2) on the high potential side. The first connection terminal 17 (C1) in the processing unit 7 (7c) is set to a reference potential by, for example, a ground terminal G or the like. The circuit board 9 (9c) of the third embodiment includes, for example, a first switching unit 27a that is set to non-conductive (OFF) in the first conducting wire 25 (L1), a second switching unit 27b that is set to conductive (ON) between the first conducting wire 25 (L1) and the second conducting wire 25 (L2), and a third switching unit 27c that is set to non-conductive (OFF) in the third conducting wire 25 (L3). The third switching unit 27c switches the conducting state of the conducting wire 25 between conductive and non-conductive by, for example, switching between mounted and unmounted so-called jumper resistors or by switching between open and closed by a switch. The first switching unit 27a, the second switching unit 27b, and the third switching unit 27c form, for example, a first switching module 27.

[0033] The first switching module 27 of the third embodiment prevents an overvoltage from occurring between the two detection terminals 19 even when an incompatible power storage module 3 is mistakenly connected to the processing unit 7 (7c). For example, the power storage module 3 shown in Fig. 4 includes k unit cells 11 with a predetermined number k that is greater than the number (m-1) of channels with a predetermined number m in the processing unit 7 (7c), and is in a state where it is mistakenly connected to the circuit board 9 (9c). 4 prevents the generation of a voltage (V3+V2+V1) between the two detection terminals 19 due to the three unit cells 11, and generates a voltage (V3+V2) due to the two unit cells 11. For example, the voltage (V3+V2) due to the two unit cells 11 is smaller than the predetermined withstand voltage of the processing unit 7 (7c), and the voltage (V3+V2+V1) due to the three unit cells 11 is an overvoltage that is larger than the predetermined withstand voltage of the processing unit 7 (7c).

[0034] As shown in FIG. 5, the circuit board 9 (9d) of the fourth embodiment includes a first conducting wire 25 (L1), a second conducting wire 25 (L2), a third conducting wire 25 (L3), and a fourth conducting wire 25 (L4), similar to the circuit board 9 (9c) of the third embodiment. The first conducting wire 25 (L1) is connected to the first terminal 21 (T1) and the first connection terminal 17 (C1) on the low potential side. The second conducting wire 25 (L2) is connected to the second terminal 21 (T2) and the second connection terminal 17 (C2) between the low potential side and the high potential side. The third conducting wire 25 (L3) is connected to the third terminal 21 (T3) and the third connection terminal 17 (C3) between the low potential side and the high potential side. The fourth conducting wire 25 (L4) is connected to the fourth terminal 21 (T4) and the fourth connection terminal 17 (C4) on the high potential side. The first connection terminal 17 (C1) in the processing unit 7 (7d) is set to a reference potential by, for example, a ground terminal G or the like. The circuit board 9 (9d) of the fourth embodiment includes, for example, a first switching unit 27a that is set to conduction (ON) with the first conducting wire 25 (L1), a second switching unit 27b that is set to non-conduction (OFF) between the first conducting wire 25 (L1) and the second conducting wire 25 (L2), and a third switching unit 27c that is set to conduction (ON) with the third conducting wire 25 (L3). The first switching unit 27a, the second switching unit 27b, and the third switching unit 27c form, for example, a first switching module 27.

[0035] When a storage module 3 that corresponds appropriately to the processing unit 7 (7d) is connected, the first switching module 27 of the fourth embodiment prevents short circuits between adjacent conductors 25 in order of potential, and properly generates the voltage of each unit cell 11 between adjacent detection terminals 19 in order of potential. For example, the storage module 3 shown in Fig. 5 includes k unit cells 11 with a predetermined number k that is the same as the number of channels (m-1) with a predetermined number m in the processing unit 7, and is properly connected to the circuit board 9 (9d).

[0036] FIG. 6 is a diagram showing a fifth example of a combination of the circuit board 9 (9e) and the processing unit 7 (7e) in the cell voltage detecting device 10 of the embodiment. The fifth embodiment shown in Figure 6 shows the configuration of the circuit board 9 (9e) in the case where, for example, the predetermined number m in the processing unit 7 is less than the predetermined number n, and therefore there is a connection terminal 17 (NC) that is not connected to any detection terminal 19 and is not involved in voltage detection by the processing unit 7 (7e).

[0037] As shown in Fig. 6, the circuit board 9 (9e) of the fifth embodiment includes, for example, a first conductive wire 25 (L1), a second conductive wire 25 (L2), ..., an (n-1)th conductive wire 25 (Ln-1), and an nth conductive wire 25 (Ln) arranged in sequence from the low potential side to the high potential side. The first conductive wire 25 (L1) is connected to the first terminal 21 (T1) and the first connection terminal 17 (C1) on the low potential side. Each of the second conductive wires 25 (L2), ..., the (n-1)th conductive wire 25 (Ln-1) is connected to each of the second terminals 21 (T2), ..., the (n-1)th terminal 21 (Tn-1) and the connection terminal 17 (NC) between the low potential side and the high potential side. The nth conductive wire 25 (Ln) is connected to the nth terminal 21 (Tn) and the second connection terminal 17 (C2) on the high potential side. The first connection terminal 17 (C1) in the processing unit 7 (7e) is set to a reference potential by, for example, a ground terminal G or the like.

[0038] The circuit board 9 (9e) of the fifth embodiment includes, for example, one first switching module 27 and (n-4) second switching modules 29. The first switching module 27 is provided, for example, on the (n-3)th conducting wire 25 (Ln-3), the (n-2)th conducting wire 25 (Ln-2), and the (n-1)th conducting wire 25 (Ln-1). The (n-4) second switching modules 29 are provided on the first conducting wire 25 (L1), the second conducting wire 25 (L2), ..., the (n-4)th conducting wire 25 (Ln-4). There is a correlation between the number of second switching modules 29, the number of connection terminals 17 (NC) that are not involved in voltage detection by the processing unit 7 (7e), and the number of unit cells 11 that correspond to the predetermined withstand voltage of the processing unit 7 (7e). For example, if the processing unit 7 (7e) has N connection terminals 17 (NC) where N is an arbitrary natural number, and the number of unit cells 11 that correspond to the predetermined withstand voltage of the processing unit 7 (7e) is M where M is an arbitrary natural number less than or equal to N, then the circuit board 9 (9e) has (NM) second switching modules 29.

[0039] The second switching module 29 includes a fourth switching unit 29a provided on the conductor 25 and a fifth switching unit 29b provided between adjacent conductors 25 in order of potential. The fifth switching unit 29b is provided, for example, between the fourth switching unit 29a and the processing unit 7 on the conductor 25 on which the fourth switching unit 29a is provided, and between the fourth switching unit 29a and the processing unit 7 on the adjacent conductor 25 on the high potential side. Each of the fourth switching unit 29a and the fifth switching unit 29b switches between conductive and non-conductive states, for example, by switching between mounting and non-mounting a so-called jumper resistor, switching between opening and closing using a switch, etc. The fourth switching unit 29a switches between conductive and non-conductive states of the conductor wires 25, and the fifth switching unit 29b switches between conductive and non-conductive states of the conductor wires 25 adjacent in order of potential.

[0040] The switching between conductive (ON) and non-conductive (OFF) of each switching unit 27a, 27b, 27c, 29a, 29b in the first switching module 27 and the second switching module 29 is set according to differences in the internal configuration, such as the connection state between the multiple connection terminals 17 and the multiple detection terminals 19 in the processing unit 7. The first switching module 27 and the second switching module 29 of the fifth embodiment prevent an overvoltage from occurring between the two detection terminals 19 even when an incompatible power storage module 3 is erroneously connected to the processing unit 7 (7e). For example, the power storage module 3 shown in FIG. 6 includes k unit cells 11, where k is a predetermined number k that is greater than the number (m-1) of channels defined by the predetermined number m in the processing unit 7 (7e), and is in a state where the power storage module 3 is erroneously connected to the circuit board 9 (9e). In this case, the first switching unit 27a and the fourth switching unit 29a are set to non-conductive (OFF), and the second switching unit 27b, the third switching unit 27c, and the fifth switching unit 29b are set to conductive (ON). 6 prevents a voltage caused by three or more unit cells 11 from being generated between the two detection terminals 19, and generates a voltage (Vn-1+Vn-2) caused by two unit cells 11. For example, the voltage (Vn-1+Vn-2) caused by two unit cells 11 is smaller than the predetermined withstand voltage of the processing unit 7 (7e), and a voltage caused by three or more unit cells 11 is an overvoltage that is larger than the predetermined withstand voltage of the processing unit 7 (7c).

[0041] In addition, when a processing unit 9 in which all connection terminals 17 are connected to detection terminals 19 is implemented on a circuit board 9 having one first switching module 27 and (n-4) second switching modules 29, the first switching unit 27a and the fourth switching unit 29a are set to conductive (ON), and the second switching unit 27b, the third switching unit 27c and the fifth switching unit 29b are set to non-conductive (OFF).

[0042] As described above, the cell voltage detection device 10 of the embodiment is provided with the first switching unit 27a and the second switching unit 27b that can be switched between conduction and non-conduction, thereby making it possible to properly accommodate the number of voltage detection channels corresponding to the number of unit cells 11 that the processing unit 7 can accommodate, without having to change the wiring pattern of the electric circuit body. For example, even if an energy storage module 3 including a greater number of unit cells 11 than the number of channels of the processing unit 7 is erroneously connected, the first switching unit 27a and the second switching unit 27b can prevent the occurrence of abnormalities such as short circuits and overvoltages. This ensures versatility in properly accommodating a plurality of processing units 7 with different numbers of channels, and also prevents abnormalities from occurring even when an energy storage module 3 that is not properly compatible with the processing unit 7 is erroneously connected.

[0043] Versatility can be improved by setting the number of second switching modules 29 by the fourth switching unit 29a and the fifth switching unit 29b, which are switched between conductive and non-conductive states, according to the number N of connection terminals 17 (NC) that are not involved in voltage detection by the processing unit 7 and the number M of unit cells 11 that corresponds to the predetermined withstand voltage of the processing unit 7. By providing (NM) second switching modules 29, it is possible to properly correspond to the number of voltage detection channels of the processing unit 7, and to prevent abnormalities such as short circuits and overvoltages even when a storage module 3 that is not properly compatible with the processing unit 7 is erroneously connected.

[0044] (Variation) Modifications of the embodiment will be described below. Note that the same parts as those in the above-described embodiment will be denoted by the same reference numerals, and descriptions thereof will be omitted or simplified. In the above-described embodiment, the predetermined withstand voltage of the processing unit 7 is greater than the voltage generated by two unit cells 11 and less than the voltage generated by three or more unit cells 11, but is not limited to this. In this case, the second switching portion 27b is not limited to being provided between adjacent conductors 25 in order of potential, but may be provided between conductors 25 selected according to the predetermined withstand voltage of the processing portion .

[0045] The embodiments of the present invention are presented as examples and are not intended to limit the scope of the invention. These embodiments can be embodied in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are intended to be included within the scope and spirit of the invention, as well as within the scope of the invention and its equivalents as defined in the claims. [Explanation of symbols]

[0046] 1...energy storage system, 3...energy storage module, 5...wire harness, 7...processing unit, 9...circuit board (electrical circuit body), 10...cell voltage detection device, 11...single cell, 13...terminal, 15...terminal, 17...connection terminal, 19...detection terminal, 21...terminal, 25...conductor, 27...first switching module, 27a...first switching section, 27b...second switching section, 27c...third switching section, 29...second switching module (switching module), 29a...fourth switching section (conductor switching section), 29b...fifth switching section (inter-conductor switching section).

Claims

1. an electric circuit body including a plurality of conductors connected to a plurality of unit cells that constitute the electricity storage module; a processing unit connected to the electric circuit body and configured to detect a voltage of each of the plurality of unit cells; The electric circuit body is at least one first switching unit provided on at least one predetermined conductor and switched between conductive and non-conductive states; at least one second switching unit that switches between conduction and non-conduction between the first switching unit and the processing unit in the conductor provided with the first switching unit and at least one predetermined conductor selected according to a predetermined withstand voltage of the processing unit; Equipped with Cell voltage detection device.

2. The processing unit a first terminal connected to the first conducting wire on the low potential side; a second terminal connected to the second conducting wire on the high potential side; N terminals connected to N different conductors, where N is an arbitrary natural number, between the first terminal and the second terminal in potential order, and which are not involved in voltage detection by the processing unit; Equipped with The electric circuit body is When the number of the unit cells corresponding to the predetermined withstand voltage is M, where M is any natural number less than or equal to the natural number N, the system includes (N-M) switching modules; The switching module includes: a conductor switching unit that switches between conduction and non-conduction of the conductor on the lower potential side of the two conductors adjacent in potential order; a conductor switching unit that switches between conduction and non-conduction between the two conductors; Equipped with The cell voltage detection device according to claim 1 .

3. The electric circuit body is a third switching section provided on the conductor adjacent to the conductor on the highest potential side connected to the second switching section, the third switching section being switched between conductive and non-conductive states; The cell voltage detection device according to claim 1 or 2.

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