Busbars and busbar modules

Abstract

To provide a busbar and a busbar module with which it is possible to improve the versatility of the busbar.SOLUTION: A busbar body 21 is formed by laminating sheet-like electro-conductive members 20 having electro-conductivity in a vertical direction Z. The electro-conductive members 20 include an upper electro-conductive member 20a that is located above in the vertical direction Z and lower electro-conductive members 20b, 20c, 20d that are located downward of the upper electro-conductive member 20a. The upper and lower electro-conductive members are electrically connected by being secured to each other by a joining part 24. The lower electro-conductive members are electrically connected to an electrode terminal 103. The upper electro-conductive member 20a includes a busbar connecting part 22 that is suitable for a voltage detection conductor 4.SELECTED DRAWING: Figure 3

Description

Technical Field

[0008] , , , , ,

[0001] The present invention relates to a bus bar and a bus bar module.

Background Art

[0002] The bus bar module is used for a battery module formed by connecting a plurality of battery cells. The bus bar module includes, for example, a plurality of bus bars that serially connect adjacent battery cells, and a voltage detection conductor electrically connected to each bus bar, in a plurality of battery cells arranged in an array direction.

[0003] The bus bar is formed of a conductive metal and is constituted by a single plate-like member.

[0004] Some bus bar modules use an electric wire as the voltage detection conductor (see, for example, Patent Document 1).

[0005] Also, some bus bar modules use a flexible printed circuit board (Flexible Printed Circuits) as the voltage detection conductor (see, for example, Patent Document 2).

[0006] When using an electric wire as the voltage detection conductor, one end of the electric wire is electrically connected, for example, by caulking to a bus bar connection portion for electric wire connection.

[0007] <ooo0024>On the other hand, when using a flexible printed circuit board as the voltage detection conductor, the circuit pattern of the flexible printed circuit board is electrically connected, for example, by solder to a bus bar connection portion for flexible printed circuit board.

Prior Art Documents

Patent Documents

[0008]

Patent Document 1

Patent Document 2

[0009] Busbar connectors for electrical wire connections and busbar connectors for flexible circuit boards have different shapes due to their different connection methods. Therefore, in conventional busbars, there are multiple voltage-sensing conductors electrically connected to the busbar connector, resulting in multiple connection configurations for each voltage-sensing conductor. Furthermore, since busbars are formed from a single sheet of metal, multiple busbar configurations exist corresponding to the different connection configurations of the busbar connector. Consequently, developers in this industry have desired improved versatility for busbars.

[0010] The present invention has been made in view of the above circumstances, and aims to provide a busbar and a busbar module that can improve the versatility of busbars. [Means for solving the problem]

[0011] To solve the above problems, the busbar according to the present invention comprises a busbar body electrically connected to the electrode terminals of a battery cell, and a busbar connection portion formed protruding from the busbar body, to which one end of a voltage detection conductor that outputs voltage information to the outside is electrically connected. The busbar body is formed by stacking conductive plate-shaped conductive members in the vertical direction, and the conductive members include an upper conductive member located above and a lower conductive member located below the upper conductive member. The upper conductive member and the lower conductive member are electrically connected to each other by a joint, the lower conductive member is electrically connected to the electrode terminals, and the upper conductive member has the busbar connection portion corresponding to the voltage detection conductor. Furthermore, the busbar connection portion protrudes horizontally from the peripheral edge of the busbar body and is directly electrically connected to the circuit pattern of the flexible printed circuit board, which is the voltage detection conductor.

[0012] To solve the above problems, the busbar module according to the present invention comprises at least a plurality of busbars connected to two or more electrode terminals of a row of electrode terminals in a battery module consisting of a plurality of battery cells arranged along an array direction, and a plurality of voltage detection conductors connected to each of the busbars, wherein the busbars comprise a busbar body electrically connected to the electrode terminals and a busbar connection portion formed protruding from the busbar body, to which one end of the voltage detection conductor that outputs voltage information to the outside is electrically connected, the busbar body is formed by stacking conductive plate-shaped conductive members in the vertical direction, the conductive members comprise an upper conductive member located above and a lower conductive member located below the upper conductive member, the upper conductive member and the lower conductive member are electrically connected to each other by a joint, the lower conductive member is electrically connected to the electrode terminals, and the upper conductive member has the busbar connection portion corresponding to the voltage detection conductor Furthermore, the busbar connection portion protrudes horizontally from the peripheral edge of the busbar body and is directly electrically connected to the circuit pattern of the flexible printed circuit board, which is the voltage detection conductor. [Effects of the Invention]

[0013] Because the busbar and busbar module according to the present invention have the above configuration, the versatility of the busbar can be improved. [Brief explanation of the drawing]

[0014] [Figure 1] Figure 1 is a perspective view of a busbar module according to the first embodiment. [Figure 2] Figure 2 is a plan view of the busbar according to the first embodiment. [Figure 3] Figure 3 is a perspective view of the busbar according to the first embodiment. [Figure 4] Figure 4 is a cross-sectional view along the line AA in Figure 2. [Figure 5] Figure 5 is a cross-sectional view along the line BB in Figure 2. [Figure 6] Figure 6 is a perspective view of a busbar according to a first modified example of the first embodiment. [Figure 7] FIG. 7 is a perspective view of a bus bar according to the second embodiment. [Figure 8] FIG. 8 is a plan view of a bus bar according to the second embodiment. [Figure 9] FIG. 9 is a perspective view of a bus bar according to the third embodiment. **Embodiments for Carrying Out the Invention**

[0015] Embodiments of a bus bar and a bus bar module according to the present invention will be described below with reference to the drawings. Note that the present invention is not limited by this embodiment. Further, the components in the following embodiments include those that can be easily assumed by those skilled in the art or those that are substantially the same.

[0016] [First Embodiment] FIG. 1 is a perspective view of a bus bar module 1 according to the first embodiment. FIG. 2 is a plan view of a bus bar 2 according to the first embodiment. FIG. 3 is a perspective view of the bus bar 2 according to the first embodiment. FIG. 4 is a cross-sectional view taken along the line A-A in FIG. 2. FIG. 5 is a cross-sectional view taken along the line B-B in FIG. 2. In FIG. 4, the details of the flexible printed circuit board 40 are shown in an omitted manner.

[0017] In FIGS. 1 to 5, X indicates the arrangement direction X of the battery cells 101 in the bus bar module 1. Y indicates the orthogonal direction Y orthogonal to the arrangement direction X of the bus bar module 1. Z indicates the vertical direction Z of the bus bar 2 and the bus bar module 1. In the bus bar 2 and the bus bar module 1 according to the present embodiment, the electrode terminal 103 side of the battery cell 101 is the lower side, and in the vertical direction Z, the side opposite to the lower side is the upper side. Further, in the bus bar module 1 according to the present embodiment, the arrangement direction X, the orthogonal direction Y, and the vertical direction Z are mutually orthogonal.

[0018] In this embodiment, the busbar module 1 is assembled to the battery module 100, as shown in Figure 1. The battery module 100 is composed of multiple battery cells 101, such as secondary batteries, arranged in the arrangement direction X, and these are modularized. The battery module 100 is used, for example, in electric vehicles (EVs) and hybrid vehicles (HVs, PHVs) to supply power to a rotating electric machine that is a drive source, or to store (charge) the power generated by the rotating electric machine. The battery module 100 makes it possible to obtain a high output that meets the requirements of the vehicle by connecting multiple battery cells 101 in series, for example.

[0019] Each battery cell 101 has a cell body 102 and two electrode terminals 103. The cell body 102 is the main part that constitutes the battery cell 101 and is formed, for example, in a substantially rectangular parallelepiped shape. The multiple electrode terminals 103 are provided in a state that is exposed to the outside relative to the cell body 102. Each battery cell 101 has, for example, a pair of electrode terminals 103 at both ends in the orthogonal direction Y. Of the pair of electrode terminals 103, the electrode terminal 103 located on one side in the orthogonal direction Y is the positive electrode terminal, and the electrode terminal 103 located on the other side in the orthogonal direction Y is the negative electrode terminal. In this embodiment, the multiple battery cells 101 are arranged in the battery module 100 in two rows of electrode terminal groups 104, each consisting of multiple electrode terminals 103 arranged in the arrangement direction X, spaced apart in the orthogonal direction Y. The battery module 100 has a busbar module 1 attached to the electrode terminal group 104, and the electrode terminals 103 (positive terminal, negative terminal) of multiple battery cells 101 are connected in series or in parallel by the busbar module 1 to perform the desired power supply function. For example, to obtain a high output that meets the requirements of a vehicle (not shown) on which the battery module 100 is installed, multiple battery cells 101 are connected in series.

[0020] The busbar module 1 is for connecting multiple battery cells 101 in series or in parallel, and as shown in Figures 1 and 2, it comprises multiple busbars 2, multiple housing cases 3, a flexible printed circuit board 40 having multiple voltage detection conductors 4, and a connector 5. The busbar module 1 outputs voltage information of the battery cells 101 connected to each busbar 2 to the outside via the voltage detection conductors 4. The voltage information is output via the connector 5 to an ECU (Electronic Control Unit) (not shown) mounted in the vehicle, and the ECU uses the acquired voltage information for charging and discharging control of the battery module 100, etc.

[0021] The busbar module 1 has a busbar 2 that electrically connects two adjacent electrode terminals 103 in the array direction X when multiple battery cells 101 are connected in series or in parallel. The busbar 2 has a busbar body 21 (described later) and a busbar connection part 22, and a voltage detection conductor 4 (described later) is provided to the busbar connection part 22.

[0022] As shown in Figures 2 and 3, the busbar 2 has a busbar body 21 and a busbar connection part 22. The busbar body 21 is formed in a substantially rectangular shape in which the length in the arrangement direction X is longer than the length in the orthogonal direction Y when viewed from the vertical direction Z. In other words, the longitudinal direction of the busbar body 21 is along the arrangement direction X, and the transverse direction is along the orthogonal direction Y. The horizontal direction, which will be described later, is a direction that is included in a plane orthogonal to the vertical direction Z and is also orthogonal to the vertical direction Z. The busbar 2 also has through holes 21H that penetrate the busbar body 21 in the vertical direction Z. The through holes 21H are arranged along the arrangement direction (longitudinal direction) X. The electrode terminals 103 of the battery cell 101 are inserted into the through holes 21H of the busbar body 21, and by welding (e.g., laser welding) the electrode terminals 103, for example, the third lower conductive member 20d located at the lowest point in the vertical direction Z is directly connected to the electrode terminals 103. Then, the other downward conductive members (in this embodiment, the first downward conductive member 20b and the second downward conductive member 20c), excluding the third downward conductive member 20d, are indirectly connected to the electrode terminals 103 via the third downward conductive member 20d. In other words, the busbar body 21 is electrically connected to the electrode terminals 103 of the battery cell 101.

[0023] The busbar body 21 is formed by stacking conductive plate-shaped conductive members 20 in the vertical direction Z. More specifically, the busbar body 21 has a plurality of plate-shaped conductive members 20 made of, for example, a conductive metal, and is constructed by stacking these plurality of conductive members 20 in the vertical direction Z. The conductive member 20 has an upper conductive member 20a located above in the vertical direction Z, and lower conductive members 20b, 20c, and 20d located below the upper conductive member 20a. The conductive member 20 of this embodiment has an upper conductive member 20a located above in the vertical direction Z, and a plurality of lower conductive members 20b, 20c, and 20d located below the upper conductive member 20a (in the example shown in Figure 3, there are three lower conductive members 20b, 20c, and 20d). The upper conductive member 20a, the first lower conductive member 20b, the second lower conductive member 20c, and the third lower conductive member 20d are formed individually. Furthermore, in this embodiment, the first lower conductive member 20b, the second lower conductive member 20c, and the third lower conductive member 20d are identical in shape and size. The upper conductive member 20a is formed separately from the lower conductive members 20b, 20c, and 20d.

[0024] The busbar body 21 of the upper conductive member 20a is formed in a substantially rectangular shape. The lower conductive members 20b, 20c, and 20d are formed in a substantially rectangular shape using only the busbar body 21. The upper conductive member 20a and each of the lower conductive members 20b, 20c, and 20d are formed to have the same shape and size. Furthermore, the thickness in the vertical direction Z of the upper conductive member 20a is the same as the thickness in the vertical direction Z of each of the lower conductive members 20b, 20c, and 20d.

[0025] The busbar connection portion 22 is formed only on the upper conductive member 20a. In other words, the upper conductive member 20a has the busbar connection portion 22. The busbar connection portion 22 is formed to protrude from the busbar body 21. More specifically, the busbar connection portion 22 is formed to protrude from the busbar body 21 in the protrusion direction, which is the orthogonal direction Y. In the busbar module 1 of this embodiment, the busbar 2 located on one side of the orthogonal direction Y and the busbar 2 located on the other side of the orthogonal direction Y have the busbar connection portion 22 protruding from the busbar body 21 in a direction that is close to each other in the orthogonal direction Y. Such a busbar connection portion 22 is formed in a substantially rectangular shape. For this reason, the length of the busbar connection portion 22 in the width direction orthogonal to the protrusion direction is the same. In this embodiment, the busbar connection portion 22 is positioned on the busbar body 21 such that the center of the arrangement direction X in the busbar connection portion 22 coincides with the center of the arrangement direction X in the busbar body 21. Furthermore, the busbar 2 has a connection through-hole 22H that penetrates the busbar connection portion 22 in the vertical direction Z. The circuit pattern 40a of the flexible printed circuit board 40 is exposed through the connection through-hole 22H, and the exposed circuit pattern 40a is electrically connected to the busbar connection portion 22 by a connecting material 23 such as solder that is filled into the connection through-hole 22H. In this embodiment, the busbar connection portion 22 protrudes horizontally from the periphery of the busbar body 21 and is electrically connected to the circuit pattern 40a of the flexible printed circuit board 40, which is the voltage detection conductor 4.

[0026] The upper conductive member 20a and the lower conductive members 20b, 20c, and 20d are electrically connected by being fixed to each other by a joint 24. The joint 24 in this embodiment is a so-called bonder, and is formed, for example, by welding both ends 20a1 of the upper conductive member 20a in the arrangement direction X to both ends 20b1, 20c1, and 20d1 of the lower conductive members 20b, 20c, and 20d in the arrangement direction X, and electrically connects the upper conductive member 20a to the plurality of lower conductive members 20b, 20c, and 20d. Alternatively, the upper conductive member 20a and the plurality of lower conductive members 20b, 20c, and 20d may be electrically connected by, for example, laser welding their ends 20a1, 20b1, 20c1, and 20d1 in the arrangement direction X to each other.

[0027] Each busbar 2 is housed in a housing case 3 by electrically connecting two or more electrode terminals 103 of an electrode terminal group 104 arranged in a row along the array direction X. More specifically, each busbar 2 is housed in a housing case 3 by electrically connecting one electrode terminal 103 and the other electrode terminal 103 of two adjacent electrode terminals 103 in the array direction X. The busbar module 1 in this embodiment has a plurality of busbars 2, and two rows of busbar groups 200, each consisting of a plurality of busbars 2 arranged in a row along the array direction X, are formed separated in the orthogonal direction Y.

[0028] The housing case 3 is made of an insulating synthetic resin and, as shown in Figure 2, has a pair of first opposing wall portions 31 facing the arrangement direction X, a pair of second opposing wall portions 32 facing the orthogonal direction Y, and a busbar housing space 3S for housing the busbar 2, which is formed by the pair of first opposing wall portions 31 and the pair of second opposing wall portions 32.

[0029] In this embodiment, the busbar module 1 has a plurality of housing cases 3, and two rows of housing case groups 300, each consisting of a plurality of housing cases 3 arranged along the arrangement direction X, are formed separated in the orthogonal direction Y. The busbar module 1 then forms a board placement space 300S for placing a flexible printed circuit board 40 between the housing case group 300 located on one side of the orthogonal direction Y and the housing case group 300 located on the other side of the orthogonal direction Y.

[0030] As shown in Figure 5, the flexible printed circuit board 40 has a base film layer 41, a conductor layer 42, and a cover film layer 43.

[0031] The base film layer 41 is formed in a flexible sheet shape from an insulating synthetic resin such as polyimide. The strength of the base film layer 41 is greater than that of the conductor layer 42 and greater than that of the cover film layer 43. In other words, the base film layer 41 is the base layer of the flexible printed circuit board 40. The surface and back surface of the sheet-shaped base film layer 41 are aligned, for example, with a plane perpendicular to the vertical direction Z.

[0032] The conductor layer 42 is formed of a conductive metal such as copper or a copper alloy, and a circuit pattern 40a is provided by this conductor layer 42. Such a conductor layer 42 is laminated on the surface of the base film layer 41 via an insulating first adhesive layer 41a. The circuit pattern 40a also includes a plurality of voltage detection conductors 4 that electrically connect the connector 5 and the busbar connection part 22. The conductor layer 42 is fixed to the surface of the base film layer 41 by the first adhesive layer 41a.

[0033] The voltage detection conductor 4 included in the circuit pattern 40a has one end electrically connected to each busbar connection 22 (see Figure 2), and the other end is electrically connected to, for example, an ECU mounted in a vehicle via a connector 5. The voltage detection conductor 4 is used for charging control of the battery module 100 by outputting voltage information of the battery cells 101 to which each busbar 2 is electrically connected.

[0034] The cover film layer 43 is formed of an insulating synthetic resin such as polypropylene, and covers the upper surface of the base film layer 41 and the upper surface of the conductor layer 42. In other words, the cover film layer 43 has the function of protecting the conductor layer 42. The cover film layer 43 is laminated onto the surface of the conductor layer 42 via an insulating second adhesive layer 42a. The cover film layer 43 is fixed to the surface of the conductor layer 42 by the second adhesive layer 42a.

[0035] Such a flexible printed circuit board 40 has a main board body 44 on which voltage detection conductors 4 electrically connected to busbar connections 22 extend linearly along the arrangement direction X, and a plurality of voltage detection conductors 4 are arranged at the same pitch in the orthogonal direction Y, and a plurality of branching parts 45 that branch from the main board body 44 to each busbar connection 22. The main board body 44 is arranged along a plane orthogonal to the vertical direction Z and is arranged under tension with respect to the arrangement direction X. The branching parts 45 have a main board adjacent part 45a located adjacent to the main board body 44 and a busbar adjacent part 45b located adjacent to the busbar connection 22. The main board adjacent part 45a is arranged along a plane orthogonal to the vertical direction Z and is arranged under tension with respect to the arrangement direction X. The busbar adjacent part 45b extends in a relaxed state with respect to the vertical direction Z. The battery module 100 generates heat when charging the battery cells 101. In this embodiment, the busbar 2 uses a flexible printed circuit board 40 for the voltage detection conductor 4 and has a substrate adjacent portion 45a that extends in a relaxed state. Therefore, the flexibility of the flexible printed circuit board 40 can suppress the effect of expansion of the housing case 3 due to the heat generated when charging the battery cell 101.

[0036] Connector 5 is electrically connected to the other end of the voltage detection conductor 4 that constitutes the circuit pattern 40a. Connector 5 then electrically connects the other end of the voltage detection conductor 4 to the other end of, for example, an electric wire that is electrically connected to the ECU mounted on the vehicle.

[0037] Next, the manufacturing method of the busbar module 1 and busbar 2 described above will be explained. First, the worker selects the voltage detection conductor 4 to be used based on the specifications of the busbar module 1 to be manufactured and the requirements of the vehicle manufacturer, etc., and determines the corresponding busbar connection part from among the multiple types of busbar connection parts. In this embodiment, the voltage detection conductor 4 used is a flexible printed circuit board 40, and the busbar connection part 22 corresponds to the voltage detection conductor 4.

[0038] Next, the worker calculates the current flowing through the busbar body 21 based on the specifications of the busbar module 1 to be manufactured and the requirements of the vehicle manufacturer, etc., and determines the number of lower conductive members to be stacked in the vertical direction Z. In this embodiment, the number of lower conductive members stacked in the vertical direction Z is 3.

[0039] Next, the worker electrically connects the lower conductive member 20d to the electrode terminal 103, and electrically connects and integrates the upper conductive member 20a and the lower conductive members 20b, 20c, and 20d by the joint 24 to form the busbar 2. Next, the worker electrically connects the voltage detection conductor 4 to the busbar connection part 22. Then, the worker houses the formed busbar 2 in the busbar housing space 3S. The worker then repeats the same process to form a busbar 2 in each housing case 3. After that, the worker forms the busbar module 1 by forming busbars 2 in all the housing cases 3.

[0040] The busbar 2 and busbar module 1 according to this embodiment have the following configuration. The busbar body 21 is formed by stacking conductive plate-shaped conductive members 20 in the vertical direction Z. The conductive members 20 have an upper conductive member 20a located above in the vertical direction Z, and lower conductive members 20b, 20c, and 20d located below the upper conductive member 20a. The upper conductive member 20a and the lower conductive members 20b, 20c, and 20d are electrically connected by fixing them to each other with a joint 24. The lower conductive members 20b, 20c, and 20d are electrically connected to the electrode terminals 103. The upper conductive member 20a has a busbar connection portion 22 corresponding to the voltage detection conductor 4. In the busbar 2 and busbar module 1 according to this embodiment, the busbar connection portion 22, which has multiple connection configurations, is provided on the upper conductive member 20a, while the electrode terminals 103 are electrically connected to the lower conductive member 20d, which is the lowest in the vertical direction. Therefore, in this embodiment, the busbar 2 and busbar module 1 change the upper conductive member 20a in accordance with the connection configuration of the voltage detection conductor 4, while eliminating the need to change the shape of the lower conductive members 20b, 20c, and 20d. As a result, the lower conductive members 20b, 20c, and 20d, which are part of the elements constituting the busbar 2, can be made common. Consequently, the busbar 2 and busbar module 1 in this embodiment can improve the versatility of the busbar 2.

[0041] The busbar 2 according to this embodiment has the following configuration. The busbar body 21 has conductive plate-shaped lower conductive members 20b, 20c, and 20d. In other words, since the busbar body 21 has a plurality of lower conductive members 20b, 20c, and 20d, the resistance of the busbar body 21 to which a high voltage is applied when connecting the electrode terminals 103 (positive terminal, negative terminal) of a plurality of battery cells 101 via the busbar 2 can be reduced. Since these lower conductive members 20b, 20c, and 20d can be standardized, the unit cost of the busbar 2 can be reduced.

[0042] The busbar 2 according to this embodiment has the following configuration. The multiple lower conductive members 20b, 20c, and 20d have the same shape and the same size, which further reduces the unit cost of the parts.

[0043] The busbar 2 according to this embodiment has the following configuration. The busbar connection portion 22 protrudes horizontally from the periphery of the busbar body 21 and is electrically connected to the circuit pattern 40a of the flexible printed circuit board 40, which is the voltage detection conductor 4. The busbar 2 is used housed in the housing case 3 of the busbar module 1, and the busbar module 1 is used in a battery module 100 which is composed of multiple battery cells 101 connected together. The battery module 100 generates heat when charging the battery cells 101 which are electrically connected to the busbar 2. In this embodiment, by using a flexible printed circuit board 40 as the voltage detection conductor 4, the effect of expansion of the housing case 3 due to the heat generated when charging the battery cells 101 can be suppressed by the flexibility of the flexible printed circuit board 40.

[0044] The busbar 2 according to this embodiment has the following configuration. The busbar 2 has a plurality of lower conductive members 20b, 20c, and 20d, and the lower conductive member 20d located at the lowest position in the vertical direction Z is directly electrically connected to the electrode terminal 103 of the battery cell 101. Therefore, with the busbar 2 according to this embodiment, the electrode terminal 103 and the lower conductive member 20d can be electrically connected by laser welding the electrode terminal 103 and the periphery of the through hole 21H of the main body of the lower conductive member 20d while only the lower conductive member 20d is housed in the housing case 3, thereby improving the workability when laser welding that part.

[0045] [First modified example of the first embodiment] Figure 6 is a plan view showing a busbar 2A of a first modified example of the first embodiment in the busbar module 1A according to the present invention. The differences in the configuration of the busbar 2A according to the first modified example compared to the configuration of the busbar 2 according to the first embodiment will be described below. When the configuration of the busbar 2 according to the first embodiment and the configuration of the busbar 2A according to the first modified example are the same, the same reference numerals are used and the description is omitted.

[0046] In the busbar 2 according to the first embodiment, the lower conductive members 20b, 20c, and 20d are formed by stacking a plurality of individually formed conductive members 20 in the vertical direction Z. On the other hand, in the busbar 2A according to the first modified example, the lower conductive members 20Ab, 20Ac, and 20Ad are integrally formed from a single plate-shaped member 201. The upper conductive member 20a of the busbar 2A according to the first modified example is formed separately from the lower conductive members 20b, 20c, and 20d. The lower conductive members 20Ab, 20Ac, and 20Ad have a plurality of fold lines 201L (two in this modified example) that extend along the longitudinal direction, which is the arrangement direction X, and are formed by folding along these fold lines 201L. The first lower conductive member 20Ab, the second lower conductive member 20Ac, and the third lower conductive member 20Ad have the same shape and the same size.

[0047] The busbar 2A according to this modified example has the following configuration: The lower conductive members 20Ab, 20Ac, and 20Ad are integrally formed from a single plate-shaped member 201. Therefore, it is possible to prevent the lower conductive members 20Ab, 20Ac, and 20Ad from separating during the assembly of the busbar 2A. As a result, the busbar 2A according to this modified example can improve workability during manufacturing.

[0048] Furthermore, in this modified busbar 2A, since the lower conductive members 20Ab, 20Ac, and 20Ad are integrally formed from a single plate-shaped member 201, there is no need to electrically connect the lower conductive members 20Ab, 20Ac, and 20Ad. For this reason, the busbar 2A can be electrically connected to the upper conductive member 20a and the lower conductive members 20Ab, 20Ac, and 20Ad by electrically connecting both ends 20a1 of the upper conductive member 20a and both ends 20b1 of the lower conductive member 20Ab with joints 24 formed by solder or the like. For this reason, there is no need to electrically connect the lower conductive member 20Ab and the lower conductive member 20Ac, and there is no need to electrically connect the lower conductive member 20Ac and the lower conductive member 20Ad.

[0049] [Second Embodiment] Figure 7 is a perspective view showing a busbar 2B of a second embodiment in the busbar module 1B according to the present invention. Figure 8 is a plan view showing a busbar 2B of a second embodiment in the busbar module 1B according to the present invention. The differences between the configuration of the busbar 2B according to the second embodiment and the configuration of the busbar 2B according to the first embodiment will be described below. When the configuration of the busbar 2 according to the first embodiment and the configuration of the busbar 2B according to the second embodiment are the same, the same reference numerals are used and the description is omitted. The upper conductive member 20a of the busbar 2B according to this embodiment is formed separately from the lower conductive members 20b, 20c, and 20d.

[0050] In the busbar 2A and busbar module 1A according to the first embodiment, the busbar connection portion 22 is electrically connected to the busbar 2 and the connector 5 via a flexible printed circuit board 40 which is a voltage detection conductor 4. In the busbar 2B and busbar module 1B according to this embodiment, the busbar connection portion 22B electrically connects the busbar 2 and the connector 5 via a wire W which is a voltage detection conductor 4. The busbar 2B according to the second embodiment will be described in detail below.

[0051] The busbar connection portion 22 has a connection body portion 211 that protrudes horizontally from the periphery of the busbar body 21, and a pair of crimping portions 212 and 213 that protrude horizontally from the connection body portion 211 in the width direction (arrangement direction X) perpendicular to the protrusion direction (orthogonal direction Y) and are spaced apart from the busbar body 21.

[0052] The electric wire W, which is the voltage detection conductor 4, has, for example, a conductive portion W1 and an insulating coating portion W2. At one end of the electric wire W, the coating portion W2 is removed to expose the conductive portion W1. With the exposed conductive portion W1 placed on the connection body portion 211 of the busbar connection portion 22B, the pair of crimping portions 212, 213 are plastically deformed so that both ends of the pair of crimping portions 212, 213 are close to each other in the width direction. In other words, the busbar connection portion 22 crimps one end of the electric wire W between the connection body portion 211 and the pair of crimping portions 212, 213 of the busbar connection portion 22 by plastically deforming the pair of crimping portions 212, 213, thereby electrically connecting the electric wire W and the busbar connection portion 22B.

[0053] Next, the manufacturing method of the busbar module 1B and busbar 2B described above will be explained. First, the worker selects the voltage detection conductor 4 to be used based on the specifications of the busbar module 1B to be manufactured and the requirements of the vehicle manufacturer, etc., and determines the corresponding busbar connection part from among the multiple types of busbar connection parts. In this embodiment, the voltage detection conductor 4 to be used is an electric wire W, and the busbar connection part 22B corresponds to the voltage detection conductor 4.

[0054] Next, the worker calculates the current flowing through the busbar body 21 based on the specifications of the busbar module 1B to be manufactured and the requirements of the vehicle manufacturer, etc., and determines the number of lower conductive members to be stacked in the vertical direction Z. In this embodiment, the number of lower conductive members stacked in the vertical direction Z is 3. Next, the worker electrically connects the lower conductive member 20d to the electrode terminal 103, and electrically connects and integrates the upper conductive member 20a and the lower conductive members 20b, 20c, and 20d by the joint 24 to form the busbar 2B. Next, the worker electrically connects the voltage detection conductor 4 to the busbar connection part 22B. Next, the worker houses the formed busbar 2B in the busbar housing space 3S of the housing case 3. Then, the worker repeats the same process, and the worker forms a busbar 2B in each housing case 3. After that, the worker forms the busbar module 1B by forming busbars 2B in all the housing cases 3.

[0055] The busbar 2 according to this embodiment has the following configuration. The busbar connection portion 22 has a connection body portion 211 and a pair of crimping portions 212 and 213 that protrude from the connection body portion 211 in the width direction (arrangement direction X) perpendicular to the protruding direction (orthogonal direction Y) and are spaced apart from the busbar body 21. One end of the electric wire W, which is the voltage detection conductor 4, is crimped between the connection body portion 211 and the pair of crimping portions 212 and 213, thereby electrically connecting the electric wire W. Therefore, the busbar 2 according to this embodiment crimps one end of the electric wire W between the connection body portion 211 and the pair of crimping portions 212 and 213 in the busbar connection portion 22 by plastically deforming the pair of crimping portions 212 and 213. As a result, the busbar 2 and busbar module 1 according to this embodiment can reliably maintain the electrical connection between one end of the electric wire W, which is the voltage detection conductor 4, and the busbar connection portion 22.

[0056] [Third Embodiment] Figure 9 is a perspective view showing a busbar 2C of a third embodiment in the busbar module 1C according to the present invention. The differences between the configuration of the busbar 2C according to the third embodiment and the configuration of the busbar 2 according to the first embodiment will be described below. When the configuration of the busbar 2 according to the first embodiment and the configuration of the busbar 2C according to the third embodiment are the same, the same reference numerals are used and the description is omitted. The upper conductive member 20Ca of the busbar 2C according to this embodiment is formed separately from the lower conductive members 20b, 20c, and 20d.

[0057] In the first embodiment, the busbar 2 was described as having a busbar body 21 and a busbar connection portion 22 provided separately. In the third embodiment, the busbar 2C uses a part of the busbar body 21 as the busbar connection portion 22. The busbar 2C according to the third embodiment will be described in detail below.

[0058] The upper conductive member 20Ca of the busbar 2C has a slit 221. In this embodiment, the slit 221 is formed in a rectangular shape and is located in the center of the upper conductive member 20Ca in the longitudinal direction (arrangement direction X) and in the center of the upper conductive member 20Ca in the short direction (orthogonal direction Y). In other words, the slit 221 is located in a portion of the upper conductive member 20Ca that is away from the peripheral edge.

[0059] The busbar connection portion 22C is provided adjacent to the slit 221, and a part of the upper conductive member 20Ca is formed by bending upward, so that the circuit pattern 40a of the flexible printed circuit board 40, which is the voltage detection conductor 4, is electrically connected.

[0060] Next, the manufacturing method of the busbar module 1C and busbar 2C described above will be explained. First, the worker selects the voltage detection conductor 4 to be used based on the specifications of the busbar module 1C to be manufactured and the requirements of the vehicle manufacturer, etc., and determines the corresponding busbar connection part from among the multiple types of busbar connection parts. In this embodiment, the voltage detection conductor 4 used is a flexible printed circuit board 40, and the busbar connection part 22C corresponds to the voltage detection conductor 4.

[0061] Next, the worker calculates the current flowing through the busbar body 21 based on the specifications of the busbar module 1C to be manufactured and the requirements of the vehicle manufacturer, etc., and determines the number of lower conductive members to be stacked in the vertical direction Z. In this embodiment, the number of lower conductive members stacked in the vertical direction Z is 3. The worker electrically connects the lower conductive member 20d to the electrode terminal 103, and electrically connects and integrates the upper conductive member 20Ca and the lower conductive members 20b, 20c, and 20d by the joint 24 to form the busbar 2C. Next, the worker electrically connects the voltage detection conductor 4 to the busbar connection part 22C. Then, the worker houses the formed busbar 2C in the busbar housing space 3S. The worker then repeats the same process to form a busbar 2C in each housing case 3. After that, the worker forms the busbar module 1C by forming busbars 2C in all the housing cases 3.

[0062] The busbar 2C according to this embodiment has the following configuration. The busbar connection portion 22C is provided adjacent to the slit 221 of the busbar body 21, and a part of the upper conductive member 20a is formed by bending upward, and the circuit pattern 40a of the flexible printed circuit board 40, which is the voltage detection conductor 4, is electrically connected. Therefore, in the busbar 2C according to this embodiment, a part of the busbar body 21 can be used as the busbar connection portion 22. Accordingly, when viewed from the vertical direction Z, the busbar 2C can suppress the increase in the plate-shaped metal material forming the upper conductive member 20a compared to a busbar where the busbar connection portion 22 is provided adjacent to the peripheral edge of the busbar body 21.

[0063] In the embodiments described above, busbars 2, 2A, 2B, and 2C were described as having three downward conductive members 20b, 20c, and 20d. However, the present invention is not limited to this, and the busbar may have one downward conductive member, two downward conductive members, or four or more downward conductive members.

[0064] Furthermore, in the first embodiment, the first modified example, and the third embodiment described above, the busbar modules 1, 1A, and 1C were described in which the voltage detection conductor 4 is a flexible printed circuit board 40. Also, in the second embodiment described above, the busbar module 1B was described in which the voltage detection conductor 4 is an electric wire W. However, the present invention is not limited thereto, and the voltage detection conductor 4 can be other conductors, such as a flat cable.

[0065] Furthermore, in the embodiments described above, the joint portion 24 that joins the upper conductive member 20a and the lower conductive members 20b, 20c, and 20d is a so-called bonder, and for example, it was described as being formed by welding both ends 20a1 of the upper conductive member 20a in the arrangement direction X and both ends 20b1, 20c1, and 20d1 of the lower conductive members 20b, 20c, and 20d in the arrangement direction X. However, the present invention is not limited thereto, and the upper conductive member 20a and the lower conductive members 20b, 20c, and 20d may be joined by soldering, or threads may be formed on the circumferential surface of the electrode terminals 103, and the electrode terminals 103 may be inserted through the main body through holes 21H, and then joined with fastening members such as nuts having screw holes for fastening to the threads on the circumferential surface of the electrode terminals, or for example, a crimping portion may be provided on the upper conductive member 20a and joined by the crimping portion.

[0066] Furthermore, in the above-described embodiment, the upper conductive member 20a and the lower conductive members 20b, 20c, and 20d are electrically connected to each other by welding or the like at both ends 20a1, 20b1, 20c1, and 20d1 in the arrangement direction X. However, the upper conductive member 20a and the lower conductive members 20b, 20c, and 20d in this embodiment are not limited to this, and may be electrically connected by welding or the like at both ends in the orthogonal direction Y, or by welding or the like at other parts.

[0067] Furthermore, in the above-described embodiment, the busbar connection portions 22, 22B, and 22C relating to the busbars 2, 2A, 2B, and 2C are described as being positioned on the busbar body 21 such that the center of the arrangement direction X in the busbar connection portions 22, 22B, and 22C coincides with the center of the arrangement direction X in the busbar body 21. However, the busbars 2, 2A, 2B, and 2C according to this embodiment are not limited to this. The busbar connection portions 22, 22B, and 22C may be positioned on the busbar body 21 such that the center of the arrangement direction X in the busbar connection portions 22, 22B, and 22C is offset from the center of the arrangement direction X in the busbar body 21. [Explanation of Symbols]

[0068] 1, 1A, 1B, 1C Busbar Modules 2, 2A, 2B, 2C busbars 20 Conductive members 20a, 20Ca Upper conductive member 20b, 20Ab Lower conductive member (first lower conductive member) 20c, 20Ac downward conductive member (second downward conductive member) 20d, 20Ad Downward conductive member (third downward conductive member) 21 Busbar body 22, 22B, 22C Busbar connection section 24 Joint 4 Voltage sensing conductor 40 Flexible Printed Circuit Boards 40a Circuit Pattern 100 Battery Modules 101 battery cells 103 Electrode terminal 211 Connection main unit 212, 213 Crimping section 221 Slit W electric wire X-axis orientation Y-direction (orthogonal direction) Z vertical direction

Claims

1. A busbar body that is electrically connected to the electrode terminals of the battery cell, A busbar connection portion is formed protruding from the busbar body, to which one end of a voltage detection conductor that outputs voltage information to the outside is electrically connected, Equipped with, The busbar body is formed by stacking conductive plate-shaped conductive members in the vertical direction, The conductive member comprises an upper conductive member located above in the vertical direction and a lower conductive member located below the upper conductive member. The upper conductive member and the lower conductive member are electrically connected by being fixed to each other at the joint. The lower conductive member is electrically connected to the electrode terminal, The upper conductive member has the busbar connection portion corresponding to the voltage detection conductor, The busbar connection portion protrudes horizontally from the periphery of the busbar body and is directly electrically connected to the circuit pattern of the flexible printed circuit board which is the voltage detection conductor. Bus bar.

2. A busbar body electrically connected to the electrode terminals of a battery cell, A busbar connection portion is formed protruding from the busbar body, to which one end of a voltage detection conductor that outputs voltage information to the outside is electrically connected, Equipped with, The busbar body is formed by stacking conductive plate-shaped conductive members in the vertical direction, The conductive member comprises an upper conductive member located above in the vertical direction and a lower conductive member located below the upper conductive member. The upper conductive member and the lower conductive member are electrically connected by being fixed to each other at the joint. The lower conductive member is electrically connected to the electrode terminal, The upper conductive member has the busbar connection portion corresponding to the voltage detection conductor, The upper conductive member has a slit, The busbar connection portion is provided adjacent to the slit, and a part of the upper conductive member is formed by bending upward, so that the circuit pattern of the flexible printed circuit board, which is the voltage detection conductor, is directly electrically connected. Bus bar.

3. A battery module comprising a plurality of battery cells arranged along the arrangement direction, comprising a plurality of busbars connected to two or more electrode terminals of a row of electrode terminals, Each of the busbars is connected to a plurality of voltage detection conductors, It has at least the following features: The aforementioned busbar is A busbar body electrically connected to the electrode terminals, A busbar connection portion is formed protruding from the busbar body, to which one end of the voltage detection conductor that outputs voltage information to the outside is electrically connected, Equipped with, The busbar body is formed by stacking conductive plate-shaped conductive members in the vertical direction, The conductive member comprises an upper conductive member located above in the vertical direction and a lower conductive member located below the upper conductive member. The upper conductive member and the lower conductive member are electrically connected by being fixed to each other at the joint. The lower conductive member is electrically connected to the electrode terminal, The upper conductive member has the busbar connection portion corresponding to the voltage detection conductor, The busbar connection portion protrudes horizontally from the periphery of the busbar body and is directly electrically connected to the circuit pattern of the flexible printed circuit board which is the voltage detection conductor. Busbar module.

4. A battery module comprising a plurality of battery cells arranged along the direction of arrangement, comprising a plurality of busbars connected to two or more electrode terminals of a row of electrode terminals, Each of the busbars is connected to a plurality of voltage detection conductors, It has at least the following features: The aforementioned busbar is A busbar body electrically connected to the electrode terminals, A busbar connection portion is formed protruding from the busbar body, to which one end of the voltage detection conductor that outputs voltage information to the outside is electrically connected, Equipped with, The busbar body is formed by stacking conductive plate-shaped conductive members in the vertical direction, The conductive member comprises an upper conductive member located above in the vertical direction and a lower conductive member located below the upper conductive member. The upper conductive member and the lower conductive member are electrically connected by being fixed to each other at the joint. The lower conductive member is electrically connected to the electrode terminal, The upper conductive member has the busbar connection portion corresponding to the voltage detection conductor, The upper conductive member has a slit, The busbar connection portion is provided adjacent to the slit, and a part of the upper conductive member is formed by bending upward, so that the circuit pattern of the flexible printed circuit board, which is the voltage detection conductor, is directly electrically connected. Busbar module.

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