Conductive module
The conductive module addresses the issue of size increase by incorporating flexible portions in its design to absorb deviations in electrode terminal pitches, enabling precise assembly and maintaining a compact form factor.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- YAZAKI CORP
- Filing Date
- 2024-11-12
- Publication Date
- 2026-05-22
Smart Images
Figure 2026084763000001_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a conductive module.
Background Art
[0002] A conductive module is a wiring module that electrically connects between a battery module in which a plurality of battery cells are arranged and a battery monitoring unit that monitors the battery state of the battery cells. This conductive module includes a bus bar that physically and electrically connects to the electrode terminals of one or a pair of battery cells of the battery module, and a flexible printed circuit board that electrically connects between the plurality of bus bars and the battery monitoring unit. The flexible printed circuit board has a main line and branch lines branched from the main line for each bus bar, and electrically connects the branch lines to the bus bars and the main line to the battery monitoring unit. This type of conductive module is disclosed in, for example, Patent Documents 1 to 3 below.
Prior Art Documents
Patent Documents
[0003]
Patent Document 1
Patent Document 2
Patent Document 3
Summary of the Invention
Problems to be Solved by the Invention
[0004] Incidentally, in battery modules, thermal expansion and contraction of battery cells, variations in manufacturing tolerances of battery cells, and variations in assembly tolerances of multiple battery cells cause deviations within the design tolerance range in the pitch between the electrode terminals of adjacent battery cells. For example, in conventional conductive modules, a tolerance absorption function to absorb this deviation is provided in the branch lines of the flexible printed circuit board. These branch lines are formed in advance into a three-dimensional shape such as an S-shape to absorb tolerances in the pitch between electrode terminals, or they are formed to bend three-dimensionally when external forces are applied to absorb the deviation. Therefore, in conventional conductive modules, space is required not only for the branch lines that connect the main line and the busbar, but also for the branch lines to exert their tolerance absorption function, which may lead to an increase in size.
[0005] Therefore, the object of the present invention is to provide a conductive module that enables the realization of tolerance absorption functionality while suppressing an increase in size. [Means for solving the problem]
[0006] The present invention comprises a busbar that is physically and electrically connected to the electrode terminals of one or a pair of battery cells in a battery module in which a plurality of battery cells are arranged, a flexible printed circuit board having circuit conductors for each busbar that electrically connect the busbar to a battery monitoring unit that monitors the battery state of the battery cells, and a busbar connection terminal for each busbar that electrically connects the busbar to the flexible printed circuit board, wherein the flexible printed circuit board has a main line extending in the direction of arrangement of the plurality of battery cells and branch lines branching from the main line for each busbar, and the busbar connection terminal has a first connection part that is physically and electrically connected to the busbar and a second connection part that is physically and electrically connected to the circuit conductor of the branch line between the busbar and the branch line for the busbar, and the main line is provided with a flexible part that is bent so as to be able to expand and contract in the direction of arrangement between adjacent branch lines in the direction of arrangement for each combination of adjacent branch lines in the direction of arrangement. [Effects of the Invention]
[0007] The conductive module according to the present invention can follow deviations in the alignment direction of the electrode terminal pitch caused by thermal expansion and contraction of battery cells by allowing each of its flexible parts to flex. Furthermore, by allowing each of its flexible parts to flex, the conductive module according to the present invention can be precisely assembled into the battery module to match deviations in the alignment direction of the electrode terminal pitch caused by manufacturing tolerance variations of battery cells or assembly tolerance variations of multiple battery cells. In this way, the conductive module according to the present invention can obtain a tolerance absorption function that suppresses an increase in its own size by allowing each of its flexible parts to flex, and consequently can also suppress an increase in the size of the battery pack. [Brief explanation of the drawing]
[0008] [Figure 1] Figure 1 is a perspective view showing a conductive module of an embodiment. [Figure 2] Figure 2 is a plan view showing a conductive module of an embodiment. [Figure 3] Figure 3 is an exploded perspective view showing a conductive module of an embodiment. [Figure 4] Figure 4 is a perspective view showing the conductive module of Modification 1. [Figure 5] Figure 5 is a plan view showing the conductive module of Modified Example 1. [Figure 6] Figure 6 is a plan view of the conductive module of Modified Example 1, seen from a different angle. [Figure 7] Figure 7 is a perspective view showing the conductive module of Modified Example 2. [Figure 8] Figure 8 is a plan view showing the conductive module of modified example 2. [Figure 9] Figure 9 is a plan view of the conductive module of Modified Example 2, seen from a different angle. [Modes for carrying out the invention]
[0009] Embodiments of the conductive module according to the present invention will be described in detail below with reference to the drawings. However, the present invention is not limited to these embodiments.
[0010] [Embodiment] One embodiment of the conductive module according to the present invention will be described with reference to Figures 1 to 3.
[0011] Reference numeral 1 in Figures 1 to 3 indicates a conductive module of this embodiment. This conductive module 1 is assembled into a battery module BM (Figures 1 to 3) in which multiple battery cells BC are arranged (for example, arranged in a single row), and electrically connects the multiple battery cells BC in this battery module BM. Furthermore, this conductive module 1 electrically connects the battery module BM to a battery monitoring unit (not shown), causing the battery monitoring unit to monitor the battery state (voltage, etc.) of the battery cells BC. This conductive module 1, together with the battery module BM, constitutes a battery pack BP (Figures 1 to 3). A battery pack BP is, for example, mounted in a vehicle (BEV: Battery Electric Vehicle, HEV: Hybrid Electric Vehicle, etc.) that is equipped with a rotating machine as a power source, and is used to supply power to the rotating machine, etc. Note that the battery module BM in the figures is a portion of multiple battery cells BC extracted.
[0012] A battery cell BC comprises a cell body BCa and positive and negative electrode terminals BCb (Figure 3). In the battery cell BC shown here, the cell body BCa is formed in a rectangular shape with six outer wall surfaces. In the multiple battery cells BC that make up the battery module BM, adjacent cell bodies BCa in the direction of arrangement are arranged with one outer wall surface facing each other. This battery module BM comprises one electrode terminal group BCc in which one electrode terminal BCb of each battery cell BC is arranged along the direction of arrangement, and the other electrode terminal group BCc in which the other electrode terminal BCb of each battery cell BC is arranged along the direction of arrangement (Figure 3).
[0013] Unless otherwise specified, the term "array direction" refers to the array direction of a plurality of battery cells BC or the array direction of a plurality of electrode terminals BCb in the electrode terminal group BCc.
[0014] In this illustration, each battery cell BC has positive and negative electrode terminals BCb on one of the six outer wall surfaces of the cell body BCa (FIG. 3). Therefore, in the battery module BM, two electrode terminal groups BCc are provided on one plane (FIG. 3).
[0015] Also, the electrode terminal BCb shown here is formed in a flat plate shape and is to be physically and electrically connected to the bus bar 10 described later by welding or the like (FIG. 3). However, the electrode terminal BCb may be formed in a post shape having a male screw portion. In this case, the bus bar 10 is fixed to the electrode terminal BCb by screwing a female screw member onto the male screw portion of the electrode terminal BCb.
[0016] The conductive module 1 includes a bus bar 10 that is physically and electrically connected to the electrode terminals BCb of one or a pair of battery cells BC in the battery module BM (FIGS. 1 to 3).
[0017] The bus bar 10 is formed of a conductive material such as metal. The bus bar 10 is a plate-shaped conductive component made of metal, and for example, it is press-formed using a metal plate as the base material. The bus bar 10 shown here is formed in a rectangular flat plate shape and is physically and electrically connected to the electrode terminal BCb by laser welding.
[0018] The bus bar 10 includes one that is physically and electrically connected to one electrode terminal BCb that serves as the total negative electrode in the battery module BM, and one that is physically and electrically connected to one electrode terminal BCb that serves as the total positive electrode in the battery module BM. Also, the bus bar 10 includes one that is physically and electrically connected to adjacent electrode terminals BCb in the array direction of a pair of battery cells BC in the battery module BM.
[0019] The conductive module 1 includes a flexible printed circuit board (FPC) 20 that electrically connects the busbar 10 to the battery monitoring unit (Figures 1 to 3).
[0020] This flexible printed circuit board 20 is equipped with a circuit conductor (not shown) for each busbar 10, and the busbar 10 and the battery monitoring unit are electrically connected via this circuit conductor. The circuit conductors on this flexible printed circuit board 20 are formed by a conductor pattern such as copper foil. This flexible printed circuit board 20 is equipped with various films (base film and cover film) that are formed flat and flexible as an insulating coating, and a conductor pattern is formed on at least one of these films (base film). The conductor pattern (circuit conductor) is enclosed by the insulating coating, and locations that serve as electrical contacts with other components are exposed, for example.
[0021] The flexible printed circuit board 20 has a main line 21 extending in the direction of the arrangement of multiple battery cells BC, and branch lines 22 branching off from this main line 21 for each busbar 10 (Figures 1 to 3). The main line 21 is provided for each electrode terminal group BCc, and branch lines 22 branch off to each busbar 10 connected to the electrode terminal BCb of the electrode terminal group BCc. The branch lines 22 branch off from the main line 21 together with the circuit conductor of the busbar 10 they serve.
[0022] The conductive module 1 is equipped with busbar connection terminals 30 for each busbar 10 that electrically connect the busbars 10 to the flexible printed circuit board 20 (Figures 1 to 3).
[0023] The busbar connection terminal 30 is positioned between the busbar 10 and the branch line 22 for the busbar 10. Between them, the busbar connection terminal 30 physically and electrically connects the first connection part 31 to the busbar 10 and the second connection part 32 to the circuit conductor of the branch line 22 (Figures 1 and 3).
[0024] The busbar connector 30 has a second connector 32 that protrudes outside the battery module BM in a direction perpendicular to the arrangement direction (Figures 1 and 3). For example, the busbar connector 30 is formed from a metal plate as the base material, creating a flat plate shape that linearly connects the first connector 31 and the second connector 32. In this example, the busbar connector 30 is formed into a rectangular flat plate shape with its longitudinal direction being the linear direction, and the second connector 32 protrudes outside the battery module BM along its longitudinal direction.
[0025] In this busbar connection terminal 30, the longitudinal direction is aligned perpendicular to the arrangement direction, and the first connection portion 31 on one plane is placed on the plane of the busbar 10, and this first connection portion 31 and the busbar 10 are physically and electrically connected, for example, by laser welding. The busbar 10 shown here is provided with a rectangular flat busbar body 11 that is physically and electrically connected to the electrode terminal BCb by laser welding, and a rectangular flat terminal connection portion 12 that protrudes from the busbar body 11 on the same plane (Figures 1 to 3). The first connection portion 31 is physically and electrically connected to the terminal connection portion 12 by laser welding.
[0026] As a result, in this busbar connection terminal 30, the second connection portion 32 protrudes outside the battery module BM in a direction perpendicular to the arrangement direction. In this busbar connection terminal 30, the second connection portion 32 on one plane is placed on the branch line 22 of the flexible printed circuit board 20, and the circuit conductors of the second connection portion 32 and the branch line 22 are physically and electrically connected by soldering. In the branch line 22, the circuit conductor is exposed at the connection point with the second connection portion 32, and the exposed portion of the circuit conductor is physically and electrically connected to the second connection portion 32 by soldering. In addition to soldering, the circuit conductors of the second connection portion 32 and the branch line 22 may be physically and electrically connected by means other than soldering, for example, by laser welding.
[0027] By the way, as mentioned earlier, in the battery module BM, there is a deviation within the design tolerance in the pitch between the electrode terminals of adjacent battery cells BC in the arrangement direction.
[0028] Therefore, in the conductive module 1, a tolerance absorption function for the pitch between electrode terminals is provided on the main line 21 of the flexible printed circuit board 20. Specifically, the main line 21 is provided with a flexible portion 21a for each combination of adjacent branch lines 22 in the arrangement direction, which is flexible so as to be able to expand and contract in the arrangement direction between adjacent branch lines 22 in the arrangement direction (Figures 1 to 3). The flexible portion 21a shown here is flexible in an arc shape between adjacent branch lines 22 on the main line 21, with each branch line 22 side being the respective end in the circumferential direction.
[0029] As a result, in this conductive module 1, if the pitch between electrode terminals widens in the alignment direction due to thermal expansion of the battery cell BC, the flexible portion 21a can be extended in the alignment direction to absorb the misalignment of the electrode terminal pitch, and if the pitch between electrode terminals narrows in the alignment direction due to thermal contraction of the battery cell BC, the flexible portion 21a can be shortened in the alignment direction to absorb the misalignment of the electrode terminal pitch. In this way, this conductive module 1 can follow the misalignment of the electrode terminal pitch in the alignment direction.
[0030] Furthermore, in this conductive module 1, even if the pitch between electrode terminals is shifted in the alignment direction due to manufacturing tolerance variations of the battery cell BC or assembly tolerance variations of multiple battery cells BC, the flexible portion 21a can be expanded or contracted in the alignment direction to match the shift, thus enabling highly accurate assembly to the battery module BM.
[0031] Furthermore, even if the pitch between electrode terminals shifts in one direction orthogonal to the arrangement direction due to thermal expansion or contraction of the battery cell BC, the conductive module 1 can follow these shifts in the pitch between electrode terminals by bending the flexible portion 21a in accordance with the shift.
[0032] Furthermore, in this conductive module 1, even if the pitch between electrode terminals shifts in one or the other direction perpendicular to the arrangement direction due to manufacturing tolerance variations of the battery cell BC or assembly tolerance variations of multiple battery cells BC, the flexible portion 21a can be bent in accordance with the shift, enabling accurate assembly to the battery module BM.
[0033] As described above, in this embodiment, the conductive module 1 has the tolerance absorption function in three mutually orthogonal directions handled by each of the deflected portions 21a of the main line 21. Therefore, this tolerance absorption function does not need to be handled by each branch line as in the conventional method, and there is no need to provide space for the branch lines to perform the tolerance absorption function. Accordingly, the conductive module 1 of this embodiment can obtain a tolerance absorption function while keeping the size of the module small.
[0034] Specifically, the conductive module 1 of this embodiment is provided with the following flexible printed circuit board 20.
[0035] The main line 21 has its width direction perpendicular to its own extension direction, and is installed adjacent to the battery module BM with its width direction aligned with the protruding direction of the second connection part 32 (Figure 1). The main line 21 shown here is formed in the shape of a rectangular flat plate with its longitudinal direction as the arrangement direction (extension direction) and its short side as the width direction.
[0036] The flexible printed circuit board 20 has a branch line 22 protruding from the end 21b on the battery module BM side in the width direction of the main line 21 (hereinafter referred to as the "first end") (Figures 1 and 3). The branch line 22 shown here is formed in a rectangular, single-piece shape that protrudes from the first end 21b on the same plane as the main line 21. The tip of the protruding end of this branch line 22 is connected to the second connection part 32 of the busbar connection terminal 30 (Figure 1). Here, the tip of the branch line 22 is tucked under the second connection part 32, and the second connection part 32, which is placed on the tip of the branch line 22, is physically and electrically connected to the circuit conductor at that tip.
[0037] In this conductive module 1, when viewed in the direction of the branch line 22 protruding from the main line 21, the longitudinal direction of the busbar connection terminal 30, and the direction of the second connection part 32 protruding to the battery module BM, each of the flexible portions 21a of the main line 21 is curved in an arc shape, allowing it to expand and contract in the direction of the arrangement. Therefore, by bending each of the flexible portions 21a of the main line 21, this conductive module 1 can follow the deviation in the arrangement direction of the electrode terminal pitch caused by thermal expansion and contraction of the battery cell BC. Furthermore, by bending each of the flexible portions 21a of the main line 21, this conductive module 1 can follow the deviation in the remaining two directions (one or the other orthogonal direction to the arrangement direction) of the electrode terminal pitch caused by thermal expansion and contraction of the battery cell BC. Furthermore, by bending each of the flexible portions 21a of the main wires 21, the conductive module 1 can be accurately assembled into the battery module BM to accommodate the misalignment of the electrode terminal pitch in the alignment direction caused by manufacturing tolerance variations of the battery cells BC and assembly tolerance variations of multiple battery cells BC. In addition, by bending each of the flexible portions 21a of the main wires 21, the conductive module 1 can be accurately assembled into the battery module BM to accommodate the misalignment of the electrode terminal pitch in the remaining two directions (one or the other orthogonal direction to the alignment direction) caused by manufacturing tolerance variations of the battery cells BC and assembly tolerance variations of multiple battery cells BC.
[0038] As described above, the conductive module 1 of this embodiment can obtain a tolerance absorption function that suppresses an increase in its own size through each of its flexible portions 21a, and consequently can also suppress an increase in the size of the battery pack BP.
[0039] Furthermore, the conductive module 1 of this embodiment connects the flexible printed circuit board 20 to the linear flat busbar connection terminal 30, which also helps to suppress the increase in size of both the module itself and the battery pack BP.
[0040] [Example 1] The conductive module 2 in this modified example is the conductive module 1 of the embodiment described above, in which the flexible printed circuit board 20 is replaced with the flexible printed circuit board 120 described below (Figures 4 to 6). Therefore, in this modified example, the same reference numerals are used for the same components and parts as in the conductive module 1 of the embodiment, and their descriptions are omitted.
[0041] The flexible printed circuit board 120 in this modified example has a main line 121 and branch lines 122, similar to the flexible printed circuit board 20 in the embodiment (Figures 4 to 6).
[0042] The main line 121 in this modified example is formed in the same manner as the main line 21 in the embodiment and is installed relative to the battery module BM in the same arrangement as the main line 21 in this embodiment. Therefore, the main line 121 in this modified example is provided with a flexible portion 121a for each combination of adjacent branch lines 122 in the arrangement direction, which is designed to bend so as to expand and contract in the arrangement direction between adjacent branch lines 122 in the arrangement direction (Figures 4 to 6). The main line 121 in this modified example has its width direction perpendicular to its own extension direction and is installed adjacent to the battery module BM with its width direction aligned with the protruding direction of the second connection portion 32 of the busbar connection terminal 30 (Figures 4 and 6).
[0043] On the other hand, the branch line 122 in this modified example is similar to the branch line 22 in the embodiment, but its shape and arrangement are changed from the branch line 22 in the embodiment as follows. First, in this modified example, the flexible printed circuit board 120 has the branch line 122 protruding from the end 121c of the main line 121 on the side opposite to the battery module BM in the width direction (hereinafter referred to as the "second end") (Figures 4 and 6). Then, this branch line 122 protrudes from the second end 121c on the same plane as the main line 121, is folded back in a U shape at the point where it protrudes, and the tip of the folded end is connected to the second connection part 32 of the busbar connection terminal 30 (Figures 4 to 6). For example, here, the flexible printed circuit board 120 is assembled to the battery module BM with the direction perpendicular to the plane of the main line 121 aligned with the vertical direction. The branch line 122 shown here is folded back in a U-shape vertically to the underside of the main line 121 and extends beyond the end (first end) 121b on the battery module BM side in the width direction of the main line 121 (Figures 4 and 6). In other words, the branch line 122 shown here is formed in a J-shape by folding back from the second end 121c side of the main line 121. The tip of this branch line 122 beyond the first end 121b is tucked under the second connection part 32, and the second connection part 32 placed on the tip of this branch line 122 is physically and electrically connected to the circuit conductor at that tip.
[0044] In this modified example, the conductive module 2, like the conductive module 1 of the embodiment, has its respective flexed portions 121a of the main line 121 bent in an arc shape, allowing expansion and contraction in the alignment direction when viewed in the direction of the branch line 122 protruding from the main line 121, the longitudinal direction of the busbar connection terminal 30, and the direction of the second connection portion 32 protruding to the battery module BM. Therefore, the conductive module 2 of this modified example, like the conductive module 1 of the embodiment, can follow the misalignment of the electrode terminal pitch in the alignment direction caused by thermal expansion and contraction of the battery cell BC. Furthermore, the conductive module 2 of this modified example, like the conductive module 1 of the embodiment, can follow the misalignment of the electrode terminal pitch in the remaining two directions (one or the other orthogonal direction to the alignment direction) caused by thermal expansion and contraction of the battery cell BC. In addition, the conductive module 2 of this modified example, like the conductive module 1 of the embodiment, can be accurately assembled to the battery module BM in accordance with the misalignment of the electrode terminal pitch in the alignment direction caused by manufacturing tolerance variations of the battery cell BC and assembly tolerance variations of multiple battery cells BC. Furthermore, the conductive module 2 of this modified example, like the conductive module 1 of the embodiment, can be accurately assembled to the battery module BM to accommodate the remaining two directions (orthogonal to one or the other direction with respect to the arrangement direction) of the electrode terminal pitch caused by manufacturing tolerance variations of the battery cell BC and assembly tolerance variations of the multiple battery cells BC.
[0045] As described above, the conductive module 2 of this modified example, like the conductive module 1 of the embodiment, has the tolerance absorption function in three mutually orthogonal directions carried out by each of the deflected portions 121a of the main line 121. Therefore, it is not necessary to have this tolerance absorption function carried out by each branch line as in the conventional method, and there is no need to provide space for the branch lines to perform the tolerance absorption function. Accordingly, the conductive module 2 of this modified example, like the conductive module 1 of the embodiment, can obtain a tolerance absorption function while suppressing an increase in size, and consequently, it can also suppress an increase in the size of the battery pack BP. Furthermore, the conductive module 2 of this modified example, like the conductive module 1 of the embodiment, has the flexible printed circuit board 120 connected to a linear flat busbar connection terminal 30, and in this respect as well, it can suppress an increase in its own size and the size of the battery pack BP.
[0046] In this modified conductive module 2, the branch line 122 is exposed in a J-shape between the main line 121 and the busbar connection terminal 30. Therefore, in this modified conductive module 2, the exposed portion of the branch line 122 may be made to perform one of the tolerance absorption functions in three mutually orthogonal directions.
[0047] [Differentiation 2] The conductive module 3 in this modified example is the conductive module 1 of the embodiment described above, in which the flexible printed circuit board 20 is replaced with the flexible printed circuit board 220 described below (Figures 7 to 9). Therefore, in this modified example, the same reference numerals are used for the same components and parts as in the conductive module 1 of the embodiment, and their descriptions are omitted.
[0048] The flexible printed circuit board 220 in this modified example has a main line 221 and branch lines 222, similar to the flexible printed circuit board 20 in the embodiment (Figures 7 to 9).
[0049] The main line 221 in this modified example is formed in the same way as the main line 21 in the embodiment. Therefore, the main line 221 in this modified example is provided with a flexible portion 221a for each combination of adjacent branch lines 222 in the direction of arrangement, which is flexible so as to be able to expand and contract in the direction of arrangement between adjacent branch lines 222 in the direction of arrangement (Figures 7 to 9).
[0050] On the other hand, the arrangement of the main line 221 in this modified example differs from that of the main line 21 in the embodiment in relation to the battery module BM. The main line 221 in this modified example has its width direction perpendicular to its own extending direction, and this width direction is aligned with the protruding direction of the second connection portion 32 of the busbar connection terminal 30. It is then arranged to overlap with multiple busbars 10 and multiple busbar connection terminals 30 with spacing between them in a direction perpendicular to both its extending direction and width direction (Figures 7 to 9). In addition, the main line 221 in this modified example is provided for each electrode terminal group BCc, just like the main line 21 in the embodiment, and is therefore arranged with spacing between it and the multiple busbar connection terminals 30 provided for each of the electrode terminal group BCc it serves.
[0051] Furthermore, the branch line 222 in this modified example is similar to the branch line 22 in the embodiment, but its shape and arrangement are changed from the branch line 22 in the embodiment as follows. First, in this modified example, the flexible printed circuit board 220 has the branch line 222 protruding from the end (hereinafter referred to as the "second end") 221c of the second connection portion 32 of the busbar connection terminal 30 in the width direction of the main line 221 (Figures 7 and 9). The second end 221c shown here faces the second connection portion 32 in the direction in which the main line 221 and the busbar connection terminal 30 are arranged opposite each other, and the branch line 222 protrudes from here toward the protruding direction of the second connection portion 32. Then, this branch line 222 protrudes from the second end 221c on the same plane as the main line 221, folds back in a U shape at the end of the protruding part, and connects the tip of the folded end to the second connection portion 32 of the busbar connection terminal 30 (Figures 7 to 9). For example, here, the flexible printed circuit board 220 is assembled to the battery module BM with the direction perpendicular to the plane of the main line 221 aligned with the vertical direction. The branch line 222 shown here is folded back in a U shape to the lower side of the main line 221 in the vertical direction. The tip of the branch line 222 that has been folded back in a U shape is tucked under the second connection part 32, and the second connection part 32, which is placed on the tip of the branch line 222, is physically and electrically connected to the circuit conductor at that tip.
[0052] In this modified conductive module 3, similar to the conductive module 1 of the embodiment, the respective flexed portions 221a of the main line 221 are curved in an arc shape, allowing expansion and contraction in the alignment direction when viewed in the direction of the protruding branch line 222 from the main line 221, the longitudinal direction of the busbar connection terminal 30, and the protruding direction of the second connection portion 32 to the battery module BM. Therefore, in the same way as the conductive module 1 of the embodiment, the conductive module 3 of this modified version can follow the alignment direction of the electrode terminal pitch caused by thermal expansion and contraction of the battery cell BC. Furthermore, in the same way as the conductive module 1 of the embodiment, the conductive module 3 of this modified version can follow the alignment direction of the electrode terminal pitch caused by thermal expansion and contraction of the battery cell BC in the remaining two directions (one or the other orthogonal direction to the alignment direction). In addition, in the same way as the conductive module 1 of the embodiment, the conductive module 3 of this modified version can be accurately assembled to the battery module BM in accordance with the alignment direction of the electrode terminal pitch caused by manufacturing tolerance variations of the battery cell BC and assembly tolerance variations of multiple battery cells BC. Furthermore, the conductive module 3 of this modified example, like the conductive module 1 of the embodiment, can be accurately assembled to the battery module BM to accommodate the remaining two directions (orthogonal to one or the other direction with respect to the arrangement direction) of the electrode terminal pitch caused by manufacturing tolerance variations of the battery cell BC and assembly tolerance variations of the multiple battery cells BC.
[0053] As described above, the conductive module 3 of this modified example, like the conductive module 1 of the embodiment, has the tolerance absorption function in three mutually orthogonal directions carried out by each of the deflected portions 221a of the main line 221. Therefore, this tolerance absorption function does not need to be carried out by each branch line as in the conventional method, and there is no need to provide space for the branch lines to perform the tolerance absorption function. Accordingly, the conductive module 3 of this modified example, like the conductive module 1 of the embodiment, can obtain a tolerance absorption function while suppressing an increase in size, and consequently, it can also suppress an increase in the size of the battery pack BP. Furthermore, the conductive module 3 of this modified example, like the conductive module 1 of the embodiment, connects the flexible printed circuit board 220 to the linear flat busbar connection terminal 30, and in this respect as well, it can suppress an increase in its own size and the size of the battery pack BP.
[0054] Furthermore, in this modified example, the conductive module 3 has the main line 221 arranged overlapping with respect to the multiple busbars 10 and multiple busbar connection terminals 30 with spacing between them. Therefore, the size of the battery pack BP can be kept down in the direction of the branch line 222 protruding from the main line 221, the longitudinal direction of the busbar connection terminals 30, the protruding direction of the second connection part 32 to the battery module BM, and the opposing arrangement direction of the pair of electrode terminal groups BCc in the battery module BM. [Explanation of symbols]
[0055] 1, 2, 3 Conductive Modules 10 Busba 20,120,220 Flexible Printed Circuit Boards 21,121,221 Main line 21a, 121a, 221a Flexible section 21b First end (end) 22,122,222 Branch Line 30 Busbar connection terminals 31. First connection section 32 Second connection section 121c, 221c 2nd end (end) BC battery cell BCb electrode terminal BM Battery Module
Claims
1. A busbar that is physically and electrically connected to the electrode terminals of one or a pair of battery cells in a battery module in which multiple battery cells are arranged, A flexible printed circuit board having circuit conductors for each busbar that electrically connect the busbars to a battery monitoring unit that monitors the battery state of the battery cells, A busbar connection terminal for each busbar that electrically connects the busbar to the flexible printed circuit board, Equipped with, The flexible printed circuit board has a main line extending in the direction of the arrangement of the plurality of battery cells, and branch lines branching off from the main line for each busbar, The busbar connection terminal physically and electrically connects the first connection portion to the busbar and the branch line for the busbar, and physically and electrically connects the second connection portion to the circuit conductor of the branch line. A conductive module characterized in that the main line is provided with a flexible portion that can be bent in the direction of the arrangement between adjacent branch lines in the direction of the arrangement, for each combination of adjacent branch lines in the direction of the arrangement.
2. The busbar connection terminal has the second connection portion protruding outside the battery module in a protruding direction perpendicular to the arrangement direction. The main line has its width direction perpendicular to its own extension direction, and is installed adjacent to the battery module with the width direction aligned with the protruding direction. The flexible printed circuit board has the branch lines protruding from the end of the main line on the battery module side in the width direction, The conductive module according to claim 1, characterized in that the branch line has a tip that protrudes from the end on the same plane as the main line and is connected to the second connection part of the busbar connection terminal.
3. The busbar connection terminal has the second connection portion protruding outside the battery module in a protruding direction perpendicular to the arrangement direction. The main line has its width direction perpendicular to its own extension direction, and is installed adjacent to the battery module with the width direction aligned with the protruding direction. The flexible printed circuit board has the branch lines protruding from the end of the main line on the side opposite to the battery module in the width direction, The conductive module according to claim 1, characterized in that the branch line protrudes from its end on the same plane as the main line, is folded back in a U-shape at the protruding end, and the tip of the folded end is connected to the second connection part of the busbar connection terminal.
4. The busbar connection terminal has the second connection portion protruding outside the battery module in a protruding direction perpendicular to the arrangement direction. The main line has a width direction perpendicular to its own extension direction, and the width direction is aligned with the projection direction, and the multiple busbars and multiple busbar connection terminals are arranged with spacing between them in a direction perpendicular to the extension direction and the width direction. The flexible printed circuit board has the branch lines protruding from the end of the main line on the protruding side in the width direction, The conductive module according to claim 1, characterized in that the branch line protrudes from its end on the same plane as the main line, is folded back in a U-shape at the protruding end, and the tip of the folded end is connected to the second connection part of the busbar connection terminal.
5. The conductive module according to claim 1, 2, 3, or 4, characterized in that the busbar connection terminal is formed in a flat plate shape that linearly connects the first connection portion and the second connection portion.