Battery monitoring device

Abstract

Battery monitoring device, comprising: a plurality of voltage measuring leads (29), each of which is designed to be electrically connected to an electrode of a plurality of elementary batteries (11) in a battery assembly (47), the battery assembly (47) consisting of the elementary batteries (11); a plurality of electronic circuits (48), each of which is designed to be connected to one of the voltage measuring lines (29) and to measure a voltage of a corresponding elementary batteries (11); a plurality of voltage measuring substrates (27), each designed to be mounted on the elementary batteries (11), with each of the voltage measuring leads (29) and each of the electronic circuits (48) being mounted on one of the respective voltage measuring substrates (27); and a communication line (31) connecting the majority of voltage measurement substrates (27) and a battery control unit (67), characterized by a plurality of housings (77, 93), each of which is formed in one piece on the corresponding plurality of voltage measuring substrates (27), and by the fact that a pair of concave electrode insertion areas (81) designed to cover a pair of electrodes in corresponding elementary batteries (11) in which the respective housing (77, 93) is formed; and a spring clamp (79) is received in each of the pair of concave electrode insertion areas (81) and is designed to electrically connect the electrode and the voltage measuring lead (29) in each of the pair of concave electrode insertion areas (81).

Description

Background of the invention1.Field of the invention

[0001] The present invention relates to a battery monitoring device. 2. Description of the state of the art

[0002] An electrical storage device which is a battery assembly has an arrangement in which a plurality of elementary batteries (battery cells) are connected in parallel to one another. Fig. In the electric storage device 501 shown in Figure 21, adjacent electrode terminals 507 of battery cells 505 are connected by a bus bar 503, and a plurality of the bus bars 503 are connected to each other by a voltage sensing line 509, such as a flexible flat cable. The voltage sensing line 509 is led out from both sides of the electrode terminals 507 of the battery cells 505, which are arranged in parallel, and is connected to a battery ECU (electronic control unit) 511, which includes a battery cell voltage sensing circuit provided in another case. Accordingly, a long interconnection is necessary for the voltage sensing line 509.

[0003] US patent application US 2014 / 0141301 A1 describes a battery condition notification unit and a battery condition monitoring system. A battery system comprises a plurality of battery packs. Each battery pack is further divided into a plurality of battery sets, each of which contains a predetermined number of unit batteries. Accordingly, each battery pack comprises the predetermined number of unit batteries multiplied by an integer number of battery sets in the battery pack. The number of battery sets is different for different battery packs of the battery system. Each of the battery sets is provided with its own subunit of a voltage sensing circuit, which is applied to a substrate and connected to unit batteries of the battery pack via corresponding voltage sensing lines.All voltage sensing circuits are connected to a common battery condition monitoring unit via a communication line.

[0004] Japanese Patent Application Laid-Open No. JP 2016-012510 A describes a voltage monitoring and balancing device for serial storage battery cells. A plurality of battery cells are connected in series and each provided with a voltage detection circuit on a respective substrate. The individual circuit components are connected to an external controller via a communication line.

[0005] Japanese Patent Application Laid-Open No. JP 2011-133418 A describes a battery pack monitoring circuit for a battery in which a plurality of battery packs are connected to each other, each with battery cell units. The battery cells are connected to battery monitoring circuits arranged on printed circuit boards. A unique assignment exists between the battery cells and the battery monitoring circuits.

[0006] To solve the above problem of the long interconnection, JP 2015-41595 A and JP 5786891 B2 disclose a structure in which a voltage measurement circuit is mounted on a substrate, and an interconnection connected to a battery ECU is derived to a single side of an electric storage device. For example, the electric storage device disclosed in JP 5786891 B2 includes a plurality of electric storage elements (battery cells) arranged in a predetermined direction, a substrate (voltage measurement substrate) through which an electrode terminal of each of the electric storage elements is passed, and a bus bar connected to the electrode terminal passed through the substrate and electrically connecting the plurality of electric storage elements.A voltage measuring line electrically connected to the electrode terminal and configured to measure a voltage of the electric storage element, and an electronic circuit to which the voltage measuring line is connected, are mounted on the substrate. According to the electric storage device, it is possible to simplify a configuration for measuring a voltage of the electric storage element, and it is possible to wire the interconnection (communication line) configured to connect the electronic circuit to the battery ECU so that it is close to a single side of the electric storage device.

[0007] However, in the battery monitoring device of the prior art electric storage device, the voltage measuring substrate has a one-piece structure in which the voltage measuring lead, which is electrically connected to the electrode terminal to measure a voltage of each of the electric storage elements, and the electronic circuit including a fuse, a resistor, a capacitor, a thermistor, a battery monitoring IC, and the like are mounted on one substrate. Accordingly, a structure is simplified, but when the number of electric storage elements in the electric storage device is changed, the same substrate cannot be used as the voltage measuring substrate. As a result, it is necessary to recreate an integrated substrate.

[0008] In addition, the substrate formed as a single plate has a disadvantage that it is difficult to accommodate a pitch tolerance (individual difference of cells, expansion) of the electrode terminal between the electrical storage elements. Summary of the invention

[0009] The invention has been made in view of the situations described above, and an object thereof is to provide a battery monitoring device capable of easily adapting to an increase and decrease in the number of elemental batteries by adding and decreasing a voltage measuring substrate, and capable of absorbing a pitch tolerance of an electrode between elemental batteries.

[0010] The object of the invention is solved by the features of patent claim 1.

[0011] According to the battery monitoring device of the present invention, the plurality of voltage measuring substrates, each mounted on the elementary batteries, and the battery control devices are connected to each other via the communication line, thereby constituting the battery monitoring device. Accordingly, even if the number of elementary batteries increases or decreases, it is possible to easily adapt to the increase or decrease by adding or reducing the voltage measuring substrate. In addition, it is also easy to print the voltage measuring line in the voltage measuring substrate as a circuit pattern, or it is also easy to arrange the communication line on a single side of the battery assembly. Accordingly, it is possible to simplify the wiring. Furthermore, in the battery monitoring device having the above-described arrangement, the plurality of voltage measuring substrates are each mounted on the plurality of elementary batteries.The plurality of voltage measuring substrates are interconnected by the communication line. Accordingly, the communication line connecting the plurality of voltage measuring substrates can accommodate electrode pitch tolerances between the plurality of elementary batteries due to individual cell differences, expansion, and the like.

[0012] In the battery monitoring device according to embodiments of the present invention, the battery monitoring device further includes a channel configured to be mounted on the battery assembly. Each of the voltage measuring substrates has an opening through which gas discharged from a valve passes and is guided to the channel. The valve is provided on each of the elementary batteries to discharge the gas generated inside a corresponding one of the elementary batteries to the outside. The channel has a one-piece structure with the plurality of voltage measuring substrates.

[0013] According to the battery monitoring device of the embodiments, the plurality of voltage measuring substrates has an integral structure with the channel, and thus, it is possible to mount the channel and the voltage measuring substrates together on the battery assembly without impairing a function of expelling the gas generated inside the elementary battery to the outside. Accordingly, assembly becomes easy. Furthermore, the number of components is reduced, thus achieving simplification of parts management. In the battery monitoring device according to the embodiments, a battery monitoring device further includes a plurality of battery monitoring modules, each of which includes a housing, each of the battery monitoring modules being mounted on a respective one of the elementary batteries.

[0014] According to the battery monitoring device of these embodiments, the battery monitoring modules including the pair of concave electrode insertion portions in the casing are respectively mounted on the elementary batteries. The spring clip is received in the concave electrode insertion portions of the casing. Each of the battery monitoring modules is mounted on each of the elementary batteries such that the pair of electrodes is inserted into the concave electrode insertion portions. The pair of electrodes inserted into the concave electrode insertion portions is electrically connected to the voltage measuring line via the spring clip. Accordingly, according to the battery monitoring device, it is possible to connect the pair of electrodes in each of the elementary batteries to the voltage measuring line via each of the battery monitoring modules simultaneously with one operation. Accordingly, the work of assembling the voltage measuring substrate becomes easy.

[0015] According to the battery monitoring device of the invention, even if the number of elementary batteries increases or decreases, it is possible to easily adapt to the increase and decrease by adding or reducing a voltage measuring substrate, and it is possible to absorb a pitch tolerance of an electrode between the elementary batteries.

[0016] The invention has been briefly described above. Furthermore, details of the invention will become clearer through the following aspect (hereinafter referred to as "embodiment") for carrying out the invention with reference to the accompanying drawings. Short description of the drawing Fig. 1 is a perspective view schematically illustrating an arrangement of an electric storage device including a battery monitoring device according to a first embodiment of the invention. Fig. 2 is a plan view of the Fig. 1 shown electrical storage device. Fig. 3 is a plan view of a Fig. 2 shown voltage measuring substrate. Fig. 4 is a sectional view showing a connection portion between an electrode of an elementary battery and the voltage measuring substrate. Fig. 5 is a view illustrating a circuit arrangement of the battery monitoring device. Fig. 6A to 6C are views illustrating an assembling process of the electric storage device having the Fig. 1 contains the battery monitoring device shown. Fig. 7A to 7C are views illustrating the same assembly process. Fig. 8A to 8C are views showing an assembling process of Modification Example 1 of the battery monitoring device in the embodiment shown in Fig. 1. Fig. 9 is a view showing the same assembly process. Fig. 10A to 10C are views showing an assembling process of Modification Example 2 of the battery monitoring device in the embodiment shown in Fig. 1. Fig. 11A to 11C are views illustrating the same assembly process. Fig. 12A and Fig. 12B are views illustrating the same assembly process. Fig. 13 is a view showing a circuit block of the battery monitoring device in the Fig. 1 represents the electrical storage device shown. Fig. 14 is a perspective view of an electrical storage device including a battery monitoring device according to a second embodiment of the invention. Fig. 15A is a perspective view illustrating a battery monitoring module of a battery monitoring device according to a third embodiment of the invention, and Fig. 15B is a sectional view of the Fig. 15A shown battery monitoring module. Fig. 16 is an enlarged sectional view of a connection portion at the main part between a voltage measuring line and a communication line of the Fig. 15B shown battery monitoring module. Fig. 17A and Fig. 17B are views illustrating an assembling process of an electric storage device having the Fig. 15 contains the battery monitoring device shown. Fig. 18A and Fig. 18B are views illustrating the same assembly process. Fig. 19A to 19C are views illustrating the same assembly processes. Fig. 20 is an enlarged sectional view of the main part showing a modification example of the connecting portion in the Fig. 16 represents the battery monitoring module. Fig. 21 is a view illustrating a prior art electric storage device in which a voltage measuring line is led out from both sides of battery cells. Detailed description of the exemplary embodiments

[0017] Embodiments of the invention are described below with reference to the attached drawings.

[0018] Fig. 1 is a perspective view schematically illustrating an arrangement of an electric storage device 100 including a battery monitoring device 110 according to a first embodiment of the invention, Fig. 2 is a plan view of the Fig. 1. Furthermore, in this embodiment, an upper and a lower direction, a front and a rear direction, and a left and a right direction are shown in Fig. 1 shown arrow directions.

[0019] The electric storage device 100 including the battery monitoring device 110 according to this embodiment can be installed in a vehicle and used as a power source that enables the vehicle to travel. That is, the electric storage device 100 can enable the vehicle to travel by converting the output electric energy into kinetic energy by a motor and generator 11. Furthermore, in the electric storage device 100, when the kinetic energy generated during vehicle braking is converted into electric energy by the motor and generator 11, the electric energy can be stored as regenerative electric power.

[0020] As in Fig. 1 and Fig. As shown in FIG. 2, the electric storage device 100 includes a plurality of element batteries 11 arranged in the front-to-rear direction. A secondary battery such as a nickel-hydrogen battery and a lithium-ion battery may be used as the element batteries 11. Here, the plurality of element batteries 11 are electrically connected in series. That is, a bus bar 13 is arranged on an upper surface of the element batteries 11. The bus bar 13 connects two element batteries 11 adjacent to each other in the front-to-rear direction in series. The number of element batteries 11 constituting the electric storage device 100 can be appropriately determined based on a required output power and the like.

[0021] Each of the elementary batteries 11 includes a rectangular battery main body 21 and a pair of positive electrode terminals 15 and 17, each protruding from one end and the other end of the upper surface 23 of the battery main body 21. The positive electrode terminal 15 is electrically connected to a positive electrode plate (current collector plate) of a power generation element in the battery main body 21. The negative electrode terminal 17 is electrically connected to a negative electrode plate (current collector plate) of the power generation element in the battery main body 21. Furthermore, a valve 25 is provided on the upper surface 23 of the battery main body 21 (see Fig. 6A to 6C). The valve 25 is provided between the positive electrode terminal 15 and the negative electrode terminal 17 in the left-right direction. The valve 25 is used to expel a gas generated inside the battery main body 21 to the outside of the battery main body 21.

[0022] For example, when overcharging the elementary battery 11 and the like are performed, there is a risk that gas, mainly from an electrolyte solution, may be generated. The battery main body 21 is in a hermetically sealed state, and thus, the internal pressure of the battery main body 21 increases in accordance with the gas generation. When the internal pressure of the battery main body 21 reaches an operating pressure of the valve 25, the valve 25 changes from a closed state to an open state, thus allowing the gas to be discharged outside the battery main body 21.

[0023] A so-called burst valve or a so-called reset valve can be used as the valve 25. In the burst valve, the valve 25 is irreversibly changed from the closed state to the open state. For example, the burst valve can be formed by cutting into the upper surface 23 of the battery main body 21. In the reset valve, on the other hand, the valve 25 is reversibly changed between the closed state and the open state. For example, it is possible to construct the reset valve using a spring.

[0024] The battery monitoring device 110 of the electric storage device 100 according to this embodiment includes a voltage measuring substrate 27, a voltage measuring line 29, an electronic circuit, and a communication line 31.

[0025] Fig. 3 is a plan view of the Fig. 2 shown voltage measuring substrate 27, Fig. Fig. 4 is a sectional view showing a connection portion between the positive electrode terminal (electrode) 15 of the elementary battery 11 and the voltage measuring substrate 27, and Fig. 5 is a view illustrating a circuit arrangement of the battery monitoring device 110.

[0026] The voltage measuring substrate 27 is mounted on each of the elementary batteries 11. A printed circuit board voltage measuring line 29 and an electronic circuit are mounted on the voltage measuring substrate 27 (see Fig. 5). A positive electrode terminal hole 33 and a negative electrode terminal hole 35, which are connected to the positive electrode terminal 15 and the negative electrode terminal 17, are provided in both ends of the voltage measuring substrate 27 in the left-right direction. A battery smoke discharge port 37 is punched between the positive electrode terminal hole 33 and the negative electrode terminal hole 35. The battery smoke discharge port 37 of the voltage measuring substrate 27 is connected to the valve 25 of the battery main body 21. A chip fuse 39 and an electronic circuit 48, such as a cell monitoring IC 49, are mounted between the battery smoke discharge port 37 and the positive electrode terminal hole 33, and between the battery smoke discharge port 37 and the negative electrode terminal hole 35, respectively.

[0027] The voltage measuring substrate 27 includes a through-hole 41 in which a conductor is provided, at an inner periphery of the hole 33 for the positive electrode terminal 15 and the hole 35 for the negative electrode terminal. The conductor of the through-hole 41 is connected to the voltage measuring line 29, which is printed in the voltage measuring substrate 27 as a conductive pattern. For example, in the voltage measuring substrate 27 in which the positive electrode terminal 15 is inserted into the hole 33 for the positive electrode terminal 15, as shown in Fig. 4, a nut 43 is screwed onto the positive electrode terminal 15. Accordingly, the positive electrode terminal 15 is electrically connected to the voltage measuring line 29 through the positive electrode terminal hole 33.

[0028] In the battery monitoring device 110 according to this embodiment, a duct 45 extending in the front-to-rear direction of a battery assembly 47 is provided on an upper surface of a plurality of voltage measuring substrates 27. A lower surface of the duct 45 is in contact with the upper surface 27 of each of the voltage measuring substrates 27. The duct 45 allows a gas discharged from the valve 25 of the elementary battery 11 to flow in through the battery smoke discharge port 37 and allows the gas to move in a direction to be removed from the battery assembly 47. For example, when the electric storage device 100 in which the battery monitoring device 110 is provided is mounted in a vehicle, the gas discharged from the valve 25 can be discharged to the outside of the vehicle using the duct 45.

[0029] In the battery monitoring device 110 of the electric storage device 100 according to this embodiment, the voltage measurement substrate 27 is mounted for each of a plurality of elementary batteries 11. The voltage measurement line 29 is provided on the voltage measurement substrate 27. Accordingly, the voltage measurement line 29 is electrically connected to the positive electrode terminal 15 and the negative electrode terminal 17 of each of the elementary batteries 11 in the battery assembly consisting of the plurality of elementary batteries 11.

[0030] As in Fig. As shown in FIG. 5, the cell monitoring IC 49 provided in the voltage measuring substrate 27 is connected to the voltage measuring line 29. The electronic circuit 48 that measures a voltage of each of the elementary batteries 11 includes a chip fuse 39, resistors 51 and 59, a capacitor 53, a cell monitoring IC 49, and the like. In addition, a thermistor may also be incorporated in the electronic circuit 48 according to this embodiment.

[0031] In the battery monitoring device 110, a cell monitoring IC 49 monitors a single element battery 11. The positive electrode terminal 15 and the negative electrode terminal 17 of each of the single element batteries 11 are connected to the cell monitoring IC 49 via the voltage measuring line 29. The chip fuse 39 is provided at each voltage measuring line 29, and the chip fuse 39 is used to prevent an excessive current from flowing from the single element battery 11 to the cell monitoring IC 49. That is, when an excessive current threatens to flow from the single element battery 11 to the cell monitoring IC 49, the chip fuse 39 blows, thus making it possible to block the connection between the single element battery 11 and the cell monitoring IC 49.

[0032] Resistor 51 is provided in voltage measurement line 29, and resistor 51 is connected in series with chip fuse 39. Resistor 51, in combination with capacitor 53, forms an RC filter and blocks a high-frequency noise component of elementary battery 11. Furthermore, resistor 51 may be omitted.

[0033] An NPN transistor 55 is provided in the electronic circuit 48. A base of the transistor 55 is connected to the cell monitor IC 49 via a discharge resistor 57. An emitter of the transistor 55 is connected to the voltage measuring line 29, which is connected to the negative electrode terminal 17 of the elementary battery 11 via the resistor 51, and a collector of the transistor 55 is connected to the voltage measuring line 29, which is connected to the positive electrode terminal 15 of the elementary battery 11 via the resistor 59. One end of the resistor 61 is connected to a region between the base and the discharge resistor 57, and the other end of the resistor 61 is connected to the voltage measuring line 29, which is connected to the cell monitor IC 49.

[0034] In the elementary battery 11, two capacitors 53 are connected in parallel via the voltage measuring line 29. One end of one of the capacitors 53 is connected to the voltage measuring line 29, which is connected to the positive electrode terminal 15 of the elementary battery 11 via the resistor 59, and its other end is connected to the voltage measuring line 29, which is connected to the negative electrode terminal 17 of the elementary battery 11. Furthermore, one end of the other capacitor 53 is connected to the voltage measuring line 29, which is connected to the positive electrode terminal 15 of the elementary battery 11 via the resistor 51, and the other end is connected to the voltage measuring line 29, which is connected to the negative electrode terminal 17 of the elementary battery 11 via the resistor 51.

[0035] Electric charges of the elementary battery 11 are charged into the capacitor 53. A voltage value of the two capacitors 53 becomes approximately equal to the voltage value of the elementary battery 11. The cell monitor IC 49 can determine the voltage value of the elementary battery 11 by measuring the voltage value of the two capacitors 53. One end of the discharge resistor 57 is connected to the cell monitor IC 49, which is connected to the positive electrode terminal 15 of the elementary battery 11. Furthermore, the other end of the discharge resistor 57 is connected to the transistor 55.

[0036] The discharge resistor 57 is used to equalize the voltage value or a charge state in a plurality of elementary batteries 11. The cell monitor IC 49 can detect a voltage value in each of the plurality of elementary batteries 11. Here, when there is a deviation in the voltage value in the plurality of elementary batteries 11, an equalization process can be performed. When the battery assembly 47 is continuously charged and discharged in a state where there is a deviation in the voltage value of the plurality of elementary batteries 11, a voltage value of only a certain elementary battery 11 may reach an upper limit voltage or a lower limit voltage. In this case, charging or discharging in other elementary batteries 11 except the certain elementary battery 11 is restricted, and thus it is difficult to perform charging and discharging efficiently.

[0037] Accordingly, when the voltage value deviation is suppressed by the equalization process, it is possible to efficiently charge and discharge all of the elementary batteries 11. For example, in the equalization process, an elementary battery 11 having the highest voltage value is determined, and the elementary battery 11 is discharged to allow a discharge current to flow to the discharge resistor 57. When the elementary battery 11 is discharged, it is possible to lower the voltage value of the elementary battery 11. In this way, it is possible to suppress a voltage value deviation in the plurality of elementary batteries 11 by discharging the elementary battery 11 having the highest voltage value.

[0038] Here, the cell monitor IC 49 includes a switch connected in series with the discharge resistor 57. When the switch is turned on, it is possible to allow a discharge current of the elementary battery 11 to flow to the discharge resistor 57. Two electrical supply lines 63 are connected to the cell monitor IC 49. One end of one of the electrical supply lines 63 is connected to the positive electrode terminal 15 via the resistor 65, and the other end is connected to a VCC terminal of the cell monitor IC 49. One end of the other electrical supply line 63 is connected to the negative electrode terminal 17, and the other end is connected to a GND (ground) terminal of the cell monitor IC 49.

[0039] A thermistor may be connected to the cell monitor IC 49. The thermistor is used to detect a temperature of the elementary battery 11. Here, one end of the thermistor is connected to the cell monitor IC 49, and the other end of the thermistor is grounded. A reference voltage in the cell monitor IC 49 is generated from a power supply voltage input from the VCC terminal and divided by a standard resistor and the thermistor. A divided voltage value is input to the cell monitor IC 49. When a resistance value of the thermistor changes according to a temperature of the elementary battery 11, a voltage value input to the cell monitor IC 49 also changes. Accordingly, the cell monitor IC 49 monitors the input voltage value to detect a temperature of the elementary battery 11.

[0040] The communication line 31 connects a plurality of voltage measurement substrates 27, each mounted on the plurality of elementary batteries 11, to interconnect the plurality of voltage measurement substrates 27 and the battery ECU 67. Furthermore, the communication line 31 can perform communication by connecting the voltage measurement substrates 27 to the battery ECU 67 in a state of dividing the voltage measurement substrates 27 into a plurality of groups, or can perform multiplex communication by integrally connecting the voltage measurement substrates 27 to the battery ECU 67. In a case of multiplex communication, a covered electric wire, which is a solid wire, can be used as the communication line 31.Furthermore, in a case of connecting the voltage measurement substrate 27 to the battery ECU 67 in a state of dividing the voltage measurement substrates 27 into the plurality of groups, a flat cable, a flexible printed circuit board, a flexible flat cable, and the like may be used. The communication line 31 may be electrically connected to the voltage measurement substrates 27 by welding, pressure welding, and the like.

[0041] Next, a description will be given of a method of assembling the electric storage device 100 including the battery monitoring device 110 configured as described above.

[0042] Fig. 6A to 6C and Fig. 7A to 7C are views showing an assembly process of the device shown in Fig. 1, which includes the battery monitoring device 110.

[0043] When assembling the battery monitoring device 110, first, as shown in Fig. 6A and Fig. 6B, the voltage measuring substrates 27 in a number corresponding to the number of elementary batteries 11 and the communication line 31 are connected to each other.

[0044] Next, as in Fig. 6C, a plurality of voltage measuring substrates 27, integrally connected on a left side by the communication line 31, are mounted on a battery assembly 47. In the battery assembly 47, the elementary batteries 11 are connected to each other in a required number by the bus bar 13.

[0045] As in Fig. As shown in Fig. 7A, in the voltage measuring substrates 27, the positive electrode terminal 15 is inserted into the positive electrode terminal hole 33, and the negative electrode terminal 17 is inserted into the negative electrode terminal hole 35. Furthermore, the battery smoke exhaust port 37 of each of the voltage measuring substrates 27 is positioned to fit the valve 25 of the elementary battery 11. Furthermore, the voltage measuring substrates 27 are fixed to the upper surface 23 of the battery main body 21 via the nut 43, which is screwed onto the positive electrode terminal 15 or the negative electrode terminal 17.

[0046] Next, as in Fig. 7B, the channel 45 is mounted on the upper surface of the plurality of voltage measuring substrates 27. The channel 45 is mounted such that the channel 45 communicates with the battery smoke discharge port 37 of the voltage measuring substrate 27.

[0047] Finally, as in Fig. 7C, the battery ECU 67 is mounted on a front surface of the battery assembly 47, and thus the communication line 31 is connected to the battery ECU 67. Accordingly, the assembly of the electric storage device 100 including the battery monitoring device 110 is completed.

[0048] Next, a description will be given of Modification Example 1 of the method for assembling the battery monitoring device 110 in the electric storage device 100 with reference to FIG. Fig. 8A to 8C and Fig. 9 given.

[0049] In the assembling method of Modification Example 1, first, as shown in Fig. 8A and Fig. 8B, the communication line 31 is integrally connected to a left side of the voltage measuring substrates 27 in a number corresponding to the number of elementary batteries 11, and the channel 45 is preliminarily mounted on the voltage measuring substrates 27 which are integrally connected.

[0050] Next, as in Fig. 8C, the integrally connected voltage measuring substrates 27, the communication line 31, and the channel 45 are mounted as the battery monitoring device 110 on the battery assembly 47. In the battery assembly 47, the elementary batteries 11 are connected to each other in a required number by the bus bar 13.

[0051] In addition, as in Fig. 9, the battery monitoring device 110 attaches the voltage measuring substrates 27 integrally connected to each other, the communication line 31 and the duct 45 to the battery assembly 47 via the nut 43 which is screwed to the positive electrode terminal 15 or the negative electrode terminal 17.

[0052] Finally, the battery ECU 67 is mounted on the front surface of the battery assembly 47, and thus the communication line 31 is connected to the battery ECU 67. Accordingly, the assembly of the electric storage device 100 including the battery monitoring device 110 is completed.

[0053] Next, a description will be given of Modification Example 2 of the method for assembling the battery monitoring device 110 in the electric storage device 100 with reference to FIG. Fig. 10A to Fig. 12B given.

[0054] In the assembling method of Modification Example 2, first, as shown in Fig. 10A and Fig. 10B, the voltage measuring substrate 27 is mounted on an elementary main body of the elementary battery 11.

[0055] Next, as in Fig. 10C, a plurality of the elementary batteries 11 on which the voltage measuring substrate 27 is mounted are combined according to the number of required cells.

[0056] As in Fig. 11A and Fig. 11B, the bus bar 13 is mounted on the positive electrode terminal 15 and the negative electrode terminal 17 in the plurality of elementary batteries 11 to electrically connect the plurality of elementary batteries.

[0057] Next, as in Fig. 11C, the communication line 31 disposed on a left side of the battery assembly 47 is connected to each of the plurality of voltage measuring substrates 27 mounted on the battery assembly 47.

[0058] Next, as in Fig. 12A, the channel 45 is mounted on the upper surface of the plurality of voltage measuring substrates 27. The channel 45 is mounted such that the channel 45 communicates with the battery smoke discharge port 37 of the voltage measuring substrate 27.

[0059] Finally, as in Fig. 12B, the battery ECU 67 is mounted on a front surface of the battery assembly 47, and thus the communication line 31 is connected to the battery ECU 67. Accordingly, the assembly of the electric storage device 100 including the battery monitoring device 110 is completed.

[0060] Next, an operation of the arrangement described above is described.

[0061] In the electrical storage device 100 according to this embodiment, as shown in Fig. As shown in Figure 13, the plurality of voltage measurement substrates 27, each mounted on the elementary batteries 11, and the battery ECU 67 are connected to each other via the communication line 31, thereby constituting the battery monitoring device 110. Accordingly, even if the number of elementary batteries 11 increases or decreases, it is possible to easily accommodate the increase or decrease by adding or reducing the voltage measurement substrate 27. In addition, it is also easy to print the voltage measurement line 29 in the voltage measurement substrate 27 as a wiring pattern, or it is also easy to arrange the communication line 31 on a single side of the battery assembly 47. Accordingly, it is possible to simplify the wiring.

[0062] Furthermore, in the battery monitoring device 110, the plurality of voltage measurement substrates 27 are respectively mounted on the plurality of elementary batteries 11. The plurality of voltage measurement substrates 27 are connected to each other by the communication line 31. Accordingly, the communication line 31 connecting the plurality of voltage measurement substrates 27 can accommodate a pitch tolerance of the positive electrode terminal 15 and the negative electrode terminal 17 between the plurality of elementary batteries 11 due to an individual difference of a cell, expansion, and the like.

[0063] In addition to this arrangement, in the battery monitoring device 110, since the electronic circuit 48 configured to measure a voltage of each of the elementary batteries 11 is mounted on each of the voltage measuring substrates 27, it is possible to downsize the battery ECU 67 corresponding to the electronic circuit 48. Accordingly, a reduction in the size and weight of components and a low profile of the components are realized. Furthermore, it is possible to replace the voltage measuring substrate 27 with a new one for each of the elementary batteries 11, thus improving component interchangeability. Furthermore, the chip fuse 39 of the voltage measuring line 29 is provided in an upstream circuit in close proximity to the elementary battery 11, thus making it possible to improve high-voltage stability.

[0064] Next, a description will be given of an electric storage device including a battery monitoring device according to a second embodiment of the invention.

[0065] Fig. 14 is a perspective view of an electronic storage device 110A according to the second embodiment, in which a voltage sensing substrate 27 and a channel 45 are integrally formed with each other. In this second embodiment, the same reference numerals are given to the same arrangement as described in the first embodiment, and redundant description thereof will not be repeated.

[0066] As is the case with the arrangement of the electric storage device 100 according to the first embodiment, in the electronic storage device 100A including the battery monitoring device 110A according to the second embodiment, an elementary battery 11 includes a valve 25 that discharges a gas generated inside to the outside. A battery smoke discharge port 37, through which the gas discharged from the valve 25 passes and is guided to the duct 45 mounted on a battery assembly 47, is formed in a voltage measuring substrate 27. On the other hand, the duct 45 has an integral structure with a plurality of the voltage measuring substrates 27. Accordingly, the duct 45 is provided integrally with a communication line 31 connected to each of the voltage measuring substrates 27.

[0067] The stress sensing substrates 27 and the channel 45 may be integrally formed beforehand or may be mechanically coupled together into a one-piece structure after being formed as a single body.

[0068] In the battery monitoring device 110A according to this second embodiment, since the plurality of voltage measuring substrates 27 have an integral structure with the duct 45, it is possible to mount the duct 45 and the voltage measuring substrates 27 together on the battery assembly 47 without impairing a function of expelling the gas generated inside the elementary battery 11. Accordingly, assembly becomes easy. Furthermore, the number of components is reduced, thus achieving simplification of parts management.

[0069] Next, a description will be given of a battery monitoring device 210 according to a third embodiment of the invention.

[0070] Fig. 15A is a perspective view illustrating a battery monitoring module 75 of a battery monitoring device 210 according to the third embodiment of the invention, Fig. 15B is a sectional view of the Fig. 15A shown battery monitoring module 75, and Fig. 16 is an enlarged main part sectional view of a connection portion between a voltage measuring line 29 and a communication line 31 of the Fig. 15B shown battery monitoring module 75.

[0071] Further, in this third embodiment, the same reference numerals are given to the same arrangement as described in the first embodiment, and redundant description thereof is not repeated.

[0072] As in Fig. 15A and Fig. 15B and Fig. 16, the battery monitoring device 210 according to this third embodiment includes the battery monitoring module 75. The battery monitoring module 75 includes a voltage measuring substrate 83, a housing 77, and a spring clip 79.

[0073] The housing 77 is formed by integrally molding a pair of concave electrode insertion portions 81 covering a positive electrode terminal 15 and a negative electrode terminal 17 in each of the elementary batteries 11, respectively, and a voltage measuring substrate 83 with an insulating resin. The voltage measuring substrate 83 is connected to the positive electrode terminal 15 and the negative electrode terminal 17 via the spring clip 79, and thus the positive electrode terminal hole 33 and the negative electrode terminal hole 35 formed in the above-described voltage measuring substrate 27 are not required. Furthermore, the voltage measuring substrate 83 is provided on an upper surface of a duct-receiving concave portion 85 formed in the housing 77, and thus the battery smoke discharge port 37 formed in the above-described voltage measuring substrate 27 is also not required.

[0074] A pair of spring clips 79 provided in the battery monitoring module 75 electrically connect the positive electrode terminal 15 and the voltage measuring line 29 in the concave electrode insertion portions 81, and electrically connect the negative electrode terminal 17 and the voltage measuring line 29. For example, the battery monitoring module 75 may be attached to the elementary battery 11 via a coupling structure 84 provided between the upper surface 23 of a battery main body 21 and the battery monitoring module 75. The battery monitoring module 75, attached to the elementary battery 11 via the coupling structure 84, may respectively bias the spring clips 79 toward the positive electrode terminal 15 and the negative electrode terminal 17 using an elastic restoring force of the spring clips 79 for elastic contact therebetween.

[0075] In the battery monitoring module 75, the voltage measurement substrate 83 is embedded in the housing 77 by molding, and the communication line 31 is arranged between the elementary battery 11 and the battery monitoring module 75. Furthermore, the battery monitoring module 75 includes a protruding pressure contact tab 87 on a lower surface. For example, a concave portion 89 preventing the pressure contact tab is formed in the upper surface 23 of the battery main body 21.

[0076] Further, the spring clips 79 may be defined as a leaf spring without being limited to a coil spring.

[0077] Next, a description will be given of a method of assembling an electric storage device 200 including the battery monitoring device 210 according to this third embodiment.

[0078] When assembling the electrical storage device 200 including the battery monitoring device 210, first, as shown in Fig. 17A and Fig. As shown in Fig. 17B, in a plurality of elementary batteries 11, a bus bar 13 is mounted on the positive electrode terminal 15 and the negative electrode terminal 17, and a duct 45 is mounted on a battery assembly 47 in which the plurality of elementary batteries 11 are electrically connected to each other. The duct 45 is arranged to cover the valve 25 of the battery main body 21.

[0079] Next, as in Fig. 18A and Fig. 18B, the communication line 31 is arranged along a left side of the battery assembly 47 to which the channel 45 is mounted.

[0080] In addition, as in Fig. 19A, the battery monitoring module 75 is arranged in a number corresponding to the number of elementary batteries 11.

[0081] Next, as in Fig. 19B, a plurality of the battery monitoring modules 75, in which the pair of concave electrode insertion portions 81 are provided in the casing 77, are sequentially mounted on the elementary batteries 11 of the battery assembly 47.

[0082] The spring clip 79 is received in the concave electrode insertion portion 81 of the housing 77. The battery monitoring modules 75 are respectively mounted on the elementary batteries 11 such that the positive electrode terminal 15 and the negative electrode terminal 17 are inserted into the concave electrode insertion portions 81. The pair of positive electrode terminal 15 and negative electrode terminal 17 inserted into the concave electrode insertion portions 81 are electrically connected to the voltage measuring line 29 via the spring clip 79. Accordingly, in the battery monitoring device 210, it is possible to connect a pair of the positive electrode terminal 15 and the negative electrode terminal 17 in each of the elementary batteries 11 to the voltage measuring line 29 through each of the battery monitoring modules 75 with one operation. Accordingly, the work of assembling the voltage measuring substrate 83 becomes easy.

[0083] Furthermore, according to the battery monitoring device 210, the communication line 31 is placed on the upper surface of the battery assembly 47 at a predetermined position, and the battery monitoring module 75 is fixed by the coupling structure 84. Accordingly, it is also possible to easily connect the voltage measuring substrate 83 and the communication line 31 with pressure contact via the pressure contact tab 87.

[0084] Finally, as in Fig. 19C, the battery ECU 67 is mounted on the front surface of the battery assembly 47, and thus the communication line 31 is connected to the battery ECU 67. Accordingly, the assembly of the electric storage device 200 including the battery monitoring device 210 is completed.

[0085] Fig. 20 is an enlarged sectional view of the main part showing a modification example of the connecting portion in the Fig.16 represents the battery monitoring module 75.

[0086] In a battery monitoring module 91 according to this modification example, a voltage measurement substrate 95 is provided integrally with the housing 93 in a state where it is exposed on an upper surface of the housing 93. The communication line 31 can be connected to the voltage measurement substrate 95 of the battery monitoring module 91 by welding and the like.

[0087] According to the battery monitoring module 91 according to this modification example, it is possible to simplify a structure of the case 93.

[0088] The above description of various embodiments is given with reference to the accompanying drawings, but it goes without saying that the invention is not limited to these examples. It will be understood by those skilled in the art that various application examples and modifications can be made within the scope described in the appended claims, and that these examples include the technical scope of the invention.

[0089] For example, in the arrangement examples described above, a description is given with reference to an example in which the electrode is composed of a columnar electrode, but the electrode may be a flat electrode. Accordingly, the connection between the voltage sensing line 29 or the bus bar 13 and the electrode may be performed by welding and the like, without being limited to screwing. Furthermore, the voltage sensing line 29 may include a typical covered electric wire, a flat cable, a flexible printed circuit board, a flexible flat cable, and the like, without being limited to printing as a wiring pattern on a substrate.

[0090] Accordingly, according to the battery monitoring devices 110, 110A, and 210 according to this embodiment, even if the number of elementary batteries 11 increases or decreases, it is possible to easily adapt to the increase or decrease by adding or reducing the voltage measuring substrate 27 or 83. Furthermore, it is also possible to absorb a pitch tolerance of the positive electrode terminal 15 and the negative electrode terminal 17 between respective elementary batteries 11.

[0091] Here, characteristics of the embodiments of the battery monitoring device according to the invention are briefly described below. [1] Battery monitoring device (110, 110A, 210) comprising: a plurality of voltage measuring leads (29), each of which is adapted to be electrically connected to an electrode (a positive electrode terminal 15 and a negative electrode terminal 17) of a respective one of a plurality of elementary batteries (11) in a battery assembly (47), the battery assembly consisting of the elementary batteries (11); a plurality of electronic circuits (48), each adapted to be connected to a respective one of the voltage measuring lines and to measure a voltage of a corresponding one of the elementary batteries; a plurality of voltage measuring substrates (27, 83) adapted to be mounted on the elementary batteries, respectively, each of the voltage measuring lines and each of the electronic circuits being mounted on a respective one of the voltage measuring substrates; and a communication line (31) connecting the plurality of voltage measuring substrates and a battery control device (a battery ECU 67). [2] Battery monitoring device (110, 110A) according to [1], further comprising: a channel (45) adapted to be mounted on the battery assembly, wherein each of the voltage measuring substrates has an opening (a battery smoke discharge opening 37) through which gas discharged from a valve (25) passes and is guided to the channel, and the valve is provided on each of the elementary batteries to discharge the gas generated inside a corresponding one of the elementary batteries to the outside; and wherein the channel has a one-piece structure with the plurality of voltage measuring substrates. [3] Battery monitoring device (210) according to [1], further comprising: a plurality of battery monitoring modules (75), each of which includes a housing (77) integrally formed on the corresponding one of the voltage measuring substrates (83), each of the battery monitoring modules being mounted on a respective one of the elementary batteries, wherein a pair of concave electrode insertion portions (81) adapted to cover a pair of electrodes in corresponding ones of the elementary batteries is formed in the respective one of the housings of the battery monitoring modules; and wherein a spring clip (79) is received in each of the pair of concave electrode insertion portions and is configured to electrically connect the electrode and the voltage measuring line in each of the pair of concave electrode insertion portions.

Claims

[1] Battery monitoring device comprising: a plurality of voltage measuring lines (29), each of which is designed to be electrically connected to an electrode of a respective one of a plurality of elementary batteries (11) in a battery assembly (47), the battery assembly (47) consisting of the elementary batteries (11); a plurality of electronic circuits (48), each of which is adapted to be connected to a respective one of the voltage measuring lines (29) and to measure a voltage of a corresponding one of the elementary batteries (11); a plurality of voltage measuring substrates (27) adapted to be mounted on the elementary batteries (11), each of the voltage measuring lines (29) and each of the electronic circuits (48) being mounted on a respective one of the voltage measuring substrates (27); and a communication line (31) connecting the plurality of voltage measuring substrates (27) and a battery control device (67), characterized by a plurality of housings (77, 93), each of which is integrally formed on the corresponding one of the plurality of voltage measuring substrates (27), and in that a pair of concave electrode insertion portions (81) adapted to cover a pair of electrodes in corresponding ones of the elementary batteries (11) is formed in the respective one of the casings (77, 93); and a spring clip (79) is received in each of the pair of concave electrode insertion portions (81) and is configured to electrically connect the electrode and the voltage measuring line (29) in each of the pair of concave electrode insertion portions (81). [2] Battery monitoring device according to claim 1, further comprising: a channel (45) designed to be mounted on the battery assembly (47), wherein each of the voltage measuring substrates (27) has an opening (37) through which gas discharged from a valve (25) passes and is guided to the channel (45), and wherein the valve (25) is provided on each of the elementary batteries (11) to discharge the gas generated inside a corresponding one of the elementary batteries (11) to the outside; and wherein the channel (45) has a one-piece structure with the plurality of voltage measuring substrates (27). [3] The battery monitoring device according to claim 1, further comprising: a plurality of battery monitoring modules (75, 91), each of which includes a housing (77, 93) of the plurality of housings (77, 93), and wherein each of the battery monitoring modules (75, 91) is mounted on a respective one of the elementary batteries (11).

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