Stacked circuit body and bus bar module

Abstract

To provide a multilayer circuit body to be used in a busbar module having high assemblability to the battery assembly and followability to deformation and manufacturing variation of the battery assembly.SOLUTION: A multilayer circuit body 20 comprises: a first circuit body 20A that is formed from a flexible substrate having a first wiring pattern; and a second circuit body 20B that is formed from a flexible substrate having a second wiring pattern and overlapped with the first circuit body 20A. The multilayer circuit body electrically connects an input terminal 30 and an output terminal. In a layered portion of the second circuit body 20B and the first circuit body 20A. an input conductor line 24 which is included in the first wiring pattern and to be connected to the input terminal 30 and an output conductor line 23 which is included in the first wiring pattern and to be connected to the output terminal are conducted and connected to each other via a relay conductor line 25 included in the second wiring pattern.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to a laminated circuit body and a bus bar module using the laminated circuit body.

Background Art

[0002] Conventionally, a bus bar module has been used, for example, to be assembled to a battery assembly (that is, a battery module in which a plurality of battery cells are laminated) as a driving power source mounted on an electric vehicle or a hybrid vehicle (see, for example, Patent Documents 1 to 3).

[0003] As an example, the bus bar module described in Patent Document 1 includes a plurality of bus bars that connect between the positive electrode and the negative electrode between adjacent battery cells laminated, and voltage detection lines connected to each of the plurality of bus bars for monitoring each battery cell. This voltage detection line is configured by bundling a plurality of electric wires having a general structure in which a core wire is covered with an insulating coating.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0005] Incidentally, generally, the battery cells constituting the battery assembly expand and contract in the stacking direction due to the operating heat associated with charge and discharge, the temperature of the external environment, and the like. As a result, the battery assembly (battery module) also deforms so as to expand and contract in the stacking direction of the battery cells. Further, due to the assembly tolerances when a plurality of battery cells are stacked and arranged, generally, the size of the battery assembly in the stacking direction may differ for each manufactured battery assembly (that is, manufacturing variations may occur). Therefore, generally, the bus bar module is designed to have a certain margin in the length of the voltage detection line so as to accommodate such deformation and manufacturing variations of the battery assembly.

[0006] However, in the conventional bus bar module described above, for example, when the number of stacked battery cells is increased for the purpose of increasing the capacity of the battery assembly, the number of wires constituting the voltage detection line also increases. As a result, when those numerous wires are bundled to form the voltage detection line, the rigidity of the entire voltage detection line (and thus the rigidity of the bus bar module) increases, and it may become difficult to improve the workability (assemblability) of assembling the bus bar module to the battery assembly. For the same reason, there is also a possibility that the bus bar module becomes difficult to expand and contract so as to sufficiently accommodate the deformation and manufacturing variations of the battery assembly.

[0007] One object of the present invention is to provide a bus bar module excellent in assemblability to a battery assembly and followability to the deformation and manufacturing variations of the battery assembly, and a stacked circuit body used for the bus bar module.

Means for Solving the Problems

[0008] In order to achieve the above-described object, the stacked circuit body and the bus bar module according to the present invention are characterized as follows.

[0009] A first circuit body composed of a flexible substrate having a first wiring pattern; A second circuit body composed of a flexible substrate having a second wiring pattern and laminated on the first circuit body; A stacked circuit body that includes and is electrically connected between an input terminal and an output terminal. In the stacked portion of the first circuit body and the second circuit body, an input conductor line included in the first wiring pattern and connected to the input terminal and an output conductor line connected to the output terminal are conductively connected to each other via a relay conductor line included in the second wiring pattern. It is a stacked circuit body.

[0010] A bus bar module attached to a battery assembly in which a plurality of single cells are stacked. The stacked circuit body according to claim 1 or claim 2. A bus bar connected to the input conductor line included in the first wiring pattern and connected to each electrode of the plurality of single cells. A connector that houses an output terminal connected to the output conductor line included in the first wiring pattern. The order of arrangement of the output conductor lines in the width direction of the stacked circuit body coincides with the order of the magnitudes of the potentials of the electrodes connected via the output conductor line, the relay conductor line, the input conductor line, and the bus bar. It is a bus bar module.

Advantages of the Invention

[0011] According to the laminated circuit body of the present invention, a first circuit body and a second circuit body composed of flexible substrates are integrated by electrically connecting a first wiring pattern and a second wiring pattern in a laminated portion between the first circuit body and the second circuit body. In other words, using this laminated circuit body, an input terminal and an output terminal can be electrically connected via an input conductor line, a relay conductor line, and an output conductor line included in the laminated circuit body. Thus, for example, if a bus bar as an input terminal and a terminal in a connector provided in a bus bar module as an output terminal are electrically connected by the laminated circuit body, when the battery assembly expands and contracts in the stacking direction due to thermal deformation of each single battery, the laminated circuit body bends or the like, so that each bus bar can move in the stacking direction of the single battery. Similarly, when the laminated circuit body bends or the like, variations in the size of the battery assembly in the stacking direction due to assembly tolerances of the single batteries can be absorbed. That is, the laminated circuit body of this configuration can easily cope with expansion and contraction of the battery assembly and manufacturing variations. Here, generally, even when a flexible substrate contains a large number of circuit structures, it is more easily deformed flexibly with a much smaller force than the electric wires used in the conventional bus bar modules described above. Therefore, the assemblability to the battery assembly is improved. Accordingly, the laminated circuit body of this configuration is superior in assemblability to the battery assembly and followability to deformation and manufacturing variations of the battery assembly compared to the electric wires used in the conventional bus bar modules described above.

[0012] Furthermore, according to the laminated circuit body of the present invention, for example, by appropriately connecting an input conductor line and an output conductor line included in the first wiring pattern in the first circuit body through a relay conductor line, the arrangement order of the output conductor lines can be rearranged in an arbitrary order different from the arrangement order of the input conductor lines (for example, swapped in the order of the magnitudes of the potentials of the input terminals to which the input conductor lines included in the first wiring pattern are connected). Thereby, compared with the case where a plurality of wiring patterns are provided in a multilayered manner in a single circuit body and such a replacement is performed, the manufacturing process of the laminated circuit body is less likely to be complicated, so that the manufacturing cost can be reduced.

[0013] As understood from the above description, the bus bar module of the present invention is excellent in the same manner as above in terms of assemblability to the battery assembly and followability to deformation and manufacturing variations of the battery assembly. Furthermore, the bus bar module of the present invention is also excellent in that the manufacturing cost is low.

[0014] As described above, the present invention has been briefly described. Furthermore, the details of the present invention will be further clarified by reading through the embodiments for carrying out the invention described below with reference to the accompanying drawings.

Brief Description of Drawings

[0015]

Figure 1

Figure 2

Figure 3

Figure 4

Embodiments for Carrying Out the Invention

[0016] <Embodiment> Hereinafter, with reference to the drawings, the bus bar module 10 according to the embodiment of the present invention will be described. The bus bar module 10 according to the present embodiment is used, for example, to be assembled to a long battery assembly 1 (see FIG. 3, a battery module in which a plurality of single cells are stacked) as a driving power source mounted on an electric vehicle.

[0017] Hereinafter, for the convenience of explanation, as shown in FIG. 1 and the like, "front", "rear", "left", "right", "upper", and "lower" are defined. The "front-rear direction", "left-right direction", and "upper-lower direction" are orthogonal to each other. The front-rear direction coincides with the stacking direction of the plurality of single cells 2 that make up the battery assembly 1 (see FIG. 3). Note that these directions are defined for the convenience of explanation and do not necessarily correspond to the front-rear direction, left-right direction, and upper-lower direction of the vehicle when the bus bar module 10 is mounted on the vehicle.

[0018] First, as a preparation for explaining the bus bar module 10, the battery assembly 1 to which the bus bar module 10 is attached will be described with reference to FIG. 3. As shown in FIG. 3, the battery assembly 1 is configured by stacking a plurality of rectangular flat plate-shaped single cells 2 extending in the up-down direction and the left-right direction in the front-rear direction. Each of the plurality of single cells 2 includes a rectangular flat plate-shaped battery body 3, a positive electrode 4 and a negative electrode 5 that project upward from both left and right ends in the left-right direction of the upper surface 6 of the battery body 3.

[0019] In the battery assembly 1, by reversing the left-right positions of the positive electrodes 4 and negative electrodes 5 of the single cells 2 adjacent to each other in the front-rear direction, the positive electrodes 4 and negative electrodes 5 are alternately arranged in the front-rear direction at each of the left end portion and the right end portion of the upper surface of the battery assembly 1, and the plurality of single cells 2 are stacked.

[0020] Hereinafter, the bus bar module 10 will be described. As shown in FIGS. 1, 2, and 4, the bus bar module 10 includes a long stacked circuit body 20 extending in the front-rear direction, a plurality of bus bars 30 respectively connected to a plurality of branch line portions 22 of the stacked circuit body 20, and a connector 40 (see FIG. 2) connected to the rear end portion of the stacked circuit body 20. Note that the main line portion 21 and the branch line portions 22 of the stacked circuit body 20 are also called "trunk line" and "branch line", respectively.

[0021] The stacked circuit body 20 is configured by stacking a first circuit body 20A and a second circuit body 20B each formed of a flexible printed circuit (FPC) that can be easily bent. Therefore, the stacked circuit body 20 (= first circuit body 20A + second circuit body 20B) can also be easily bent.

[0022] As shown in FIG. 1, the first circuit body 20A includes a strip-shaped main line portion 21 extending in the front-rear direction, and a plurality of branch line portions 22 extending so as to branch outward in the left-right direction from a plurality of locations in the front-rear direction of the main line portion 21. The connector 40 is connected to the rear end portion of the main line portion 21 of the first circuit body 20A. The surface of the first circuit body 20A is formed of a resin layer except for the portions where the contact portions p and q described later are exposed (see FIG. 1), and includes the "first wiring pattern". The first circuit body 20A is a so-called "single-sided flexible printed circuit board (single-sided FPC)" having a single wiring layer, and the "first wiring pattern" is arranged on the single wiring layer. Details of the "first wiring pattern" will be described later.

[0023] The second circuit body 20B has a strip-shaped shape extending in the front-rear direction corresponding to the main line portion 21 of the first circuit body 20A, and is laminated on the upper surface of the portion excluding the vicinity of the front end of the main line portion 21 of the first circuit body 20A (see FIGS. 2 and 4). The surface of the second circuit body 20B is formed of a resin layer except for the portions where the contact portions r and s described later are exposed (see FIG. 1), and includes the "second wiring pattern". The second circuit body 20B is a so-called "single-sided flexible printed circuit board (single-sided FPC)" having a single wiring layer, and the "second wiring pattern" is arranged on the single wiring layer. Details of the "second wiring pattern" will be described later.

[0024] A metal bus bar 30 is connected to the tip of each branch line portion 22 of the first circuit body 20A. As a result, on each of the left and right sides of the main line portion 21, a plurality of bus bars 30 are arranged in a row at intervals in the front-rear direction (see FIG. 1). Each bus bar 30 has a substantially rectangular flat plate shape extending in the front-rear direction and has a pair of front-rear through holes 31. The interval in the front-rear direction between the pair of front-rear through holes 31 is equal to the interval in the front-rear direction between the positive electrode 4 and the negative electrode 5 adjacent in the front-rear direction in the battery assembly 1.

[0025] Hereinafter, the details of the "first wiring pattern" included in the first circuit body 20A and the "second wiring pattern" included in the second circuit body 20B, and the lamination procedure of the second circuit body 20B on the first circuit body 20A will be described. For convenience of explanation, as shown in FIG. 4, a plurality (specifically, nine) of bus bars 30 and a plurality (nine) of symbols A, B, C, D, E, F, G, H, I are associated with each other one-to-one. On the right side of the main line portion 21, five bus bars 30 corresponding to the symbols A, C, E, G, I are arranged in the front-rear direction, and on the left side of the main line portion 21, four bus bars 30 corresponding to the symbols B, D, F, H are arranged in the front-rear direction.

[0026] As shown in FIG. 1 and the like, in the first circuit body 20A, an output conductor line 23 and an input conductor line 24 are arranged in the single wiring layer corresponding to each of the nine bus bars 30 (all the bus bars 30 arranged on the left and right) corresponding to the symbols A to I as the "first wiring pattern". In the second circuit body 20B, a relay conductor line 25 is arranged in the single wiring layer corresponding to each of the four bus bars 30 (the four bus bars 30 excluding the foremost bus bar among the five bus bars 30 arranged on the right side) corresponding to the symbols C, E, G, I as the "second wiring pattern". Each of the output conductor line 23, the input conductor line 24, and the relay conductor line 25 is a copper conductor extending in a strip shape.

[0027] In the first circuit body 20A, the nine output conductor lines 23 corresponding to the bus bars 30 of the symbols A to I are arranged so as to be arranged in the left-right direction from right to left in the order of the symbols A→I, and extend in the front-rear direction forward along the main line portion 21 from the rear end of the main line portion 21 (see FIG. 4). The front-rear direction position of the front end of each of the nine output conductor lines 23 corresponding to the bus bars 30 of the symbols A to I coincides with the front-rear direction position of the root portion of the corresponding branch line portion 22. The rear ends of the nine output conductor lines 23 are independently connected one-to-one to a plurality (nine) of output terminals (not shown) accommodated in a connector 40 (see FIG. 2) connected to the rear end of the main line portion 21.

[0028] In the first circuit body 20A, nine input conductor lines 24 corresponding to nine bus bars 30 labeled A to I respectively extend along branch line portions 22 corresponding to the bus bars 30 labeled A to I. Each of the nine input conductor lines 24 is connected to the corresponding bus bar 30 at the tip of the corresponding branch line portion 22. The output conductor lines 23 and the input conductor lines 24 corresponding to each of the five bus bars 30 labeled A, B, D, F, and H are directly conductively connected within the main line portion 21. On the other hand, the output conductor lines 23 and the input conductor lines 24 corresponding to each of the four bus bars 30 labeled C, E, G, and I are not connected within the main line portion 21, but are conductively connected to each other via corresponding relay conductor lines 25 provided in the second circuit body 20B. The ends of the input conductor lines 24 corresponding to each of the four bus bars 30 labeled C, E, G, and I on the side opposite to the bus bars 30 are located within the main line portion 21 near the root of the corresponding branch line portion 22.

[0029] As a result, each of the five bus bars 30 corresponding to A, B, D, F, and H is individually conductively connected to the corresponding output terminal in the connector 40 through the corresponding input conductor line 24 and the corresponding output conductor line 23 in this order. Each of the four bus bars 30 corresponding to C, E, G, and I is individually conductively connected to the corresponding output terminal in the connector 40 through the corresponding input conductor line 24, the corresponding relay conductor line 25, and the corresponding output conductor line 23 in this order. The connector 40 is connected to an external voltage detection device (not shown). Thereby, each of the nine bus bars 30 corresponding to A to I is individually conductively connected to the external voltage detection device through the connector 40. The details of the "first wiring pattern" included in the first circuit body 20A and the "second wiring pattern" included in the second circuit body 20B have been described above.

[0030] Next, the lamination procedure of the second circuit body 20B onto the first circuit body 20A will be described. As shown in FIG. 1, on the upper surface of the first circuit body 20A, at positions directly above the ends on the side opposite to the bus bars 30 of the four input conductor lines 24 corresponding to the four bus bars 30 of symbols C, E, G, and I, metal contact portions p electrically connected to the respective ends are provided so as to be exposed, and at positions directly above the front ends of the four output conductor lines 23 corresponding to the four bus bars 30 of symbols C, E, G, and I, metal contact portions q electrically connected to the respective front ends are provided so as to be exposed. On the lower surface of the second circuit body 20B, corresponding to the four contact portions p provided on the first circuit body 20A, at positions directly below the right ends of the four relay conductor lines 25 extending in the left-right direction corresponding to the four bus bars 30 of symbols C, E, G, and I, metal contact portions r electrically connected to the respective right ends are provided so as to be exposed, and corresponding to the four contact portions q provided on the first circuit body 20A, at positions directly below the left ends of the four relay conductor lines 25 extending in the left-right direction corresponding to the four bus bars 30 of symbols C, E, G, and I, metal contact portions s electrically connected to the respective left ends are provided so as to be exposed.

[0031] When laminating the second circuit body 20B onto the upper surface of the first circuit body 20A, first, the second circuit body 20B is placed on the upper surface of the main line portion 21 of the first circuit body 20A such that the corresponding contact portions p and r are arranged to face each other in the vertical direction, and the corresponding contact portions q and s are arranged to face each other in the vertical direction. Next, the corresponding contact portions p and r, and the corresponding contact portions q and s are each soldered one-to-one independently of each other. These soldering operations can typically be performed by a method (so-called pulse heat method) in which paste-like solder is sandwiched between the contact portions p and r and the contact portions q and s arranged to face each other in the vertical direction, and then a heater tip capable of heating the solder to a meltable temperature is pressed against the soldering location and the heater tip is heated to perform soldering. Note that the soldering can also be performed by a reflow method using a heating furnace. Further, the electrical connection between the corresponding contact portions p and r, and the corresponding contact portions q and s may be performed using a conductive adhesive instead of the above-described soldering.

[0032] As described above, the output conductor line 23 and the input conductor line 24 provided in the first circuit body 20A corresponding to each of the four bus bars 30 of the symbols C, E, G, and I are conductively connected to each other via the corresponding relay conductor line 25 provided in the second circuit body 20B, and the second circuit body 20B is laminated on the upper surface of the first circuit body 20A. The above describes the lamination procedure of the second circuit body 20B on the first circuit body 20A.

[0033] As described above, the bus bar module 10 shown in FIGS. 2 and 4 is assembled on the upper surface of the battery assembly 1 via a resin holder (not shown) that holds the laminated circuit body 20 and the plurality of bus bars 30, such that the corresponding positive electrode 4 and negative electrode 5 adjacent to each other in the front-rear direction are respectively inserted into the pair of through holes 31 of each bus bar 30.

[0034] In the state where the bus bar module 10 is assembled to the battery assembly 1, each bus bar 30 conductively connects the corresponding positive electrode 4 and negative electrode 5 adjacent to each other in the front-rear direction, so that the plurality of single cells 2 constituting the battery assembly 1 are electrically connected in series via the plurality of bus bars 30. As a result, the potentials of the nine bus bars 30 corresponding to the symbols A to I gradually increase in the order of the symbols A → I. As described above, in the first circuit body 20A, the nine output conductor lines 23 corresponding to the bus bars 30 of the symbols A to I are arranged so as to be aligned in the left-right direction from right to left in the order of the symbols A → I (see FIG. 4). In this way, in the laminated circuit body 20, the arrangement order of the nine output conductor lines 23 arranged in the first circuit body 20A is replaced with the potential order of the bus bars 30 connected to the input conductor lines 24 arranged in the first circuit body 20A through the relay conductor lines 25 arranged in the second circuit body 20B. Thereby, compared with the case where a plurality of wiring patterns are provided in a multilayer manner in a single circuit body and such replacement is performed, the manufacturing process of the laminated circuit body 20 is less likely to be complicated, and thus the manufacturing cost can be reduced.

[0035] In the usage state of the battery assembly 1 to which the bus bar module 10 is attached, each single battery 2 constituting the battery assembly 1 expands and contracts in the stacking direction (front-rear direction) due to the operating heat associated with charging and discharging, the temperature of the external environment, etc. As a result, the battery assembly 1 also deforms so as to expand and contract in the stacking direction (front-rear direction). Also, due to the assembly tolerance when stacking and arranging the plurality of single batteries 2, generally, the size of the battery assembly 1 in the stacking direction (front-rear direction) can differ for each manufactured battery assembly 1 (manufacturing variations can occur).

[0036] In this regard, in the bus bar module 10, even if expansion and contraction of the battery assembly 1 in the stacking direction (front-rear direction) and manufacturing variations of the battery assembly 1 occur due to thermal deformation of each single battery 2, each branch line portion 22 made of a flexible substrate easily bends, so that the expansion and contraction and manufacturing variations due to thermal deformation of the battery assembly 1 can be easily absorbed.

[0037] <Function and Effect> As described above, according to the bus bar module 10 according to the present embodiment, the first circuit body 20A and the second circuit body 20B each composed of a flexible substrate are integrated in the laminated portion of the first circuit body 20A and the second circuit body 20B by electrically connecting the first wiring pattern (output conductor lines 23 and input conductor lines 24) and the second wiring pattern (relay conductor line 25). In other words, the input terminal (bus bar 30) and the output terminal (the output terminal in the connector 40) are electrically connected via the input conductor lines 24, the relay conductor line 25, and the output conductor lines 23 included in the laminated circuit body 20. Thus, for example, if the bus bar 30 as an input terminal and the output terminal in the connector 40 as an output terminal are electrically connected by the laminated circuit body 20, when the battery assembly 1 expands and contracts in the stacking direction due to thermal deformation of each single battery 2, the laminated circuit body 20 bends or the like, and each bus bar 30 can move in the stacking direction of the single battery 2. Similarly, by bending or the like of the laminated circuit body 20, variations in the size of the battery assembly 1 in the stacking direction due to assembly tolerances of the single battery 2 can be absorbed. In other words, the bus bar module 10 according to the present embodiment can easily cope with expansion and contraction of the battery assembly 1 and manufacturing variations. Here, generally, even when a flexible substrate encloses a large number of circuit structures, it is more easily deformed flexibly with a much smaller force than the electric wires used in the conventional bus bar modules described above. Therefore, the assemblability to the battery assembly 1 is improved. Accordingly, the bus bar module 10 according to the present embodiment is superior in assemblability to the battery assembly 1 and followability to deformation and manufacturing variations of the battery assembly 1 as compared with the conventional bus bar modules described above.

[0038] Furthermore, according to the bus bar module 10 according to the present embodiment, the arrangement order of the output conductor lines 23 included in the first wiring pattern in the first circuit body 20A can be rearranged in an arbitrary order (for example, swapped in the potential order of the bus bars 30 to which the input conductor lines 24 included in the first wiring pattern are connected) through the relay conductor line 25 included in the second wiring pattern. Thereby, compared with the case where a plurality of wiring patterns are provided in a multilayer manner in a single circuit body and such swapping is performed, the manufacturing process of the bus bar module 10 is less likely to be complicated, and thus the manufacturing cost can be reduced.

[0039] Furthermore, the first circuit body 20A is a circuit body having a single wiring layer (for example, a single-sided flexible substrate), and the second circuit body 20B is a circuit body having a single wiring layer (for example, a single-sided flexible substrate). Thus, similar to the above, the manufacturing cost of the stacked circuit body 20 can be reduced compared to the case where the entire first circuit body 20A and second circuit body 20B are constituted by a circuit body having a plurality of wiring layers.

[0040] <Other embodiments> Note that the present invention is not limited to the above-described embodiments, and various modifications can be adopted within the scope of the present invention. For example, the present invention is not limited to the above-described embodiments, and can be appropriately modified, improved, etc. In addition, the material, shape, dimensions, number, arrangement location, etc. of each component in the above-described embodiments are arbitrary as long as the present invention can be achieved, and are not limited.

[0041] Here, the features of the embodiments of the stacked circuit body 20 and the bus bar module 10 according to the present invention described above are briefly summarized and listed below in [1] to [3] respectively.

[0042] [1] A first circuit body (20A) composed of a flexible substrate having a first wiring pattern, A second circuit body (20B) composed of a flexible substrate having a second wiring pattern and laminated on the first circuit body (20A), A stacked circuit body (20) comprising: and electrically connecting between an input terminal (30) and an output terminal, In a stacked portion of the first circuit body (20A) and the second circuit body (20B), an input conductor line (24) included in the first wiring pattern and connected to the input terminal (30) and an output conductor line (23) connected to the output terminal are conductively connected to each other via a relay conductor line (25) included in the second wiring pattern. Stacked circuit body (20).

[0043] According to the laminated circuit body having the configuration of [1] above, a first circuit body and a second circuit body each formed of a flexible substrate are integrated by electrically connecting a first wiring pattern and a second wiring pattern at the laminated portion between the first circuit body and the second circuit body. In other words, an input terminal and an output terminal are electrically connected via an input conductor line, a relay conductor line, and an output conductor line included in the laminated circuit body. Thus, for example, if a bus bar as an input terminal and a terminal in a connector provided in a bus bar module as an output terminal are electrically connected by the laminated circuit body, when the battery assembly expands and contracts in the stacking direction due to thermal deformation of each single battery, the laminated circuit body bends or the like, and each bus bar can move in the stacking direction of the single batteries. Similarly, by bending or the like of the laminated circuit body, variations in the size of the battery assembly in the stacking direction due to assembly tolerances of the single batteries can be absorbed. In other words, the laminated circuit body having this configuration can easily cope with expansion and contraction of the battery assembly and manufacturing variations. Here, generally, even when the flexible substrate includes a number of circuit structures, it is more easily deformed flexibly with a much smaller force than the electric wire used for the conventional bus bar module described above. Therefore, the assemblability to the battery assembly is improved. Accordingly, the laminated circuit body having this configuration is superior in assemblability to the battery assembly and followability to deformation and manufacturing variations of the battery assembly compared to the electric wire used for the conventional bus bar module described above.

[0044] Furthermore, according to the laminated circuit body having the above configuration, for example, the arrangement order of the output conductor lines included in the first wiring pattern in the first circuit body can be rearranged in an arbitrary order (for example, rearranged in the order of the potentials of the input terminals to which the input conductor lines included in the first wiring pattern are connected) through the relay conductor lines included in the second wiring pattern. Thereby, compared with the case where a plurality of wiring patterns are provided in a multilayered manner in a single circuit body and such rearrangement is performed, the manufacturing process of the laminated circuit body is less likely to be complicated, and thus the manufacturing cost can be reduced.

[0045] [2] In the laminated circuit body (20) described in [1] above, the first circuit body (20A) is, It has a single wiring layer and is configured such that the first wiring pattern is disposed on the single wiring layer. The second circuit body (20B) has a single wiring layer and is configured such that the second wiring pattern is disposed on the single wiring layer. A stacked circuit body (20).

[0046] According to the stacked circuit body having the configuration of [2] above, the first circuit body is a circuit body having a single wiring layer (for example, a single-sided flexible substrate), and the second circuit body is a circuit body having a single wiring layer (for example, a single-sided flexible substrate). Thus, similarly to the above, the manufacturing cost of the stacked circuit body can be reduced as compared with the case where the entire first circuit body and the second circuit body are configured by a circuit body having a plurality of wiring layers.

[0047] [3] A bus bar module (10) attached to a battery assembly (1) in which a plurality of single cells (2) are stacked, the stacked circuit body (20) described in [1] or [2] above, a bus bar (30) connected to the input conductor line (24) included in the first wiring pattern and connected to each electrode (4, 5) of the plurality of single cells (2), and a connector (40) that houses the output terminal connected to the output conductor line (23) included in the first wiring pattern. The bus bar module (10) is provided, wherein the arrangement order of the output conductor lines (23) in the width direction of the stacked circuit body (20) matches the order of the magnitudes of the potentials of the electrodes (4, 5) connected via the output conductor line (23), the relay conductor line (25), the input conductor line (24), and the bus bar (30). A bus bar module (10).

[0048] According to the bus bar module configured as described above [3], a first circuit body and a second circuit body each composed of a flexible substrate are integrated by electrically connecting a first wiring pattern and a second wiring pattern at the laminated portion between the first circuit body and the second circuit body. In other words, the input terminal and the output terminal are electrically connected via the input conductor line, the relay conductor line, and the output conductor line included in the laminated circuit body. Thus, for example, if a bus bar as an input terminal and a terminal in the connector of the bus bar module as an output terminal are electrically connected by the laminated circuit body, when the battery assembly expands and contracts in the stacking direction due to thermal deformation of each single battery, the laminated circuit body bends or the like, so that each bus bar can move in the stacking direction of the single battery. Similarly, by bending or the like of the laminated circuit body, variations in the size of the battery assembly in the stacking direction due to assembly tolerances of the single batteries can be absorbed. In other words, the bus bar module of this configuration can easily cope with expansion and contraction of the battery assembly and manufacturing variations. Here, the flexible substrate generally deforms flexibly with a much smaller force than the electric wire used for the conventional bus bar module described above, even when including a large number of circuit structures. Therefore, the assemblability to the battery assembly is improved. Accordingly, the bus bar module of this configuration is superior in assemblability to the battery assembly and in followability to deformation and manufacturing variations of the battery assembly compared to the conventional bus bar module described above.

[0049] Furthermore, according to the bus bar module configured as described above, for example, the arrangement order of the output conductor lines included in the first wiring pattern in the first circuit body can be rearranged in an arbitrary order (for example, rearranged in the potential order of the input terminals to which the input conductor lines included in the first wiring pattern are connected) through the relay conductor lines included in the second wiring pattern. Thereby, compared with the case where a plurality of wiring patterns are provided in a multilayered manner in a single circuit body and such rearrangement is performed, the manufacturing process of the bus bar module is less likely to be complicated, so that the manufacturing cost can be reduced.

Explanation of Reference Numerals

[0050] 1 Battery assembly 2 Single battery 4 Positive electrode (electrode) 5 Negative electrode (electrode) 10 Bus bar module 20 Stacked circuit body 20A First circuit body 20B Second circuit body 23 Output conductor line 24 Input conductor line 25 Relay conductor line 30 Bus bar (input terminal) 40 Connector

Claims

1. A first circuit body composed of a flexible substrate having a first wiring pattern, A second circuit body composed of a flexible substrate having a second wiring pattern and laminated on the first circuit body, A laminated circuit body that includes the above and electrically connects between an input terminal and an output terminal, In the laminated portion of the first circuit body and the second circuit body, an input conductor line included in the first wiring pattern and connected to the input terminal and an output conductor line connected to the output terminal are conductively connected to each other via a relay conductor line included in the second wiring pattern. Laminated circuit body.

2. In the laminated circuit body according to Claim 1, The first circuit body, Has a single wiring layer, and is configured such that the first wiring pattern is arranged on the single wiring layer, The second circuit body, Has a single wiring layer, and is configured such that the second wiring pattern is arranged on the single wiring layer, Laminated circuit body.

3. A bus bar module attached to a battery assembly in which a plurality of single cells are laminated, The laminated circuit body according to Claim 1 or Claim 2, A bus bar connected to the input conductor line included in the first wiring pattern and connected to each electrode of the plurality of single cells, A connector that houses the output terminal connected to the output conductor line included in the first wiring pattern, and includes: The arrangement order of the output conductor lines in the width direction of the laminated circuit body is the same as the order of the magnitudes of the potentials of the electrodes connected via the output conductor line, the relay conductor line, the input conductor line, and the bus bar. Bus bar module.

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