Busbar Module

Abstract

To provide a bus bar module capable of improving the degree of freedom in design.SOLUTION: A bus bar module 1 comprises: a plurality of bus bars 2 fixed to battery cells 120 of a battery module 110; and a plate-like circuit body 3 having flexibility. The circuit body has: a trunk line part 30 that extends in a first direction X in which a plurality of battery cells are arranged; and a plurality of branch parts 31 branched from the trunk line part. The plurality of branch parts include a coupling branch part 32 connected with two bus bars. The coupling branch part has a first fixed part 35 fixed to a first bus bar 23, a second fixed part 37 fixed to a second bus bar 24, a first extending part 34, and a second extending part 36. The first extending part extends in the first direction between the trunk line part and the first fixed part. The second extending part extends in the first direction between the first fixed part and the second fixed part. The second extending part has such a length that the first and second bus bars can be fixed to the battery cells while bending and deforming the second extending part.SELECTED DRAWING: Figure 4

Description

[Technical field]

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

[0002] There are busbar modules in the past. Patent Document 1 discloses a battery connection module having a flexible circuit board including a main body and a plurality of L-shaped flexible arms extending from the main body. The L-shaped flexible arm of Patent Document 1 includes a first section extending outward from the main body toward the plurality of busbars, a second section connecting with the first section and extending in a direction between the plurality of busbars and the main body, and an end portion positioned at a distal end of the second section and connecting with a corresponding busbar. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2019-23996 A Summary of the Invention [Problem to be solved by the invention]

[0004] There is still room for improvement in terms of improving the degree of freedom in design of a busbar module. More specifically, it is desirable to improve the degree of freedom in design of a configuration in which branches are branched from a trunk of a circuit body and the branches are connected to a busbar. For example, it is preferable to ensure the followability of the busbar to the battery cells while avoiding interference between other components and the branches. For example, if the number of necessary branches can be reduced, the degree of freedom in designing the circuit body can be improved.

[0005] An object of the present invention is to provide a busbar module that can improve the degree of freedom in design. [Means for solving the problem]

[0006] The busbar module of the present invention includes a battery module having a plurality of battery cells, a plurality of bus bars fixed to the battery cells, and a flexible, plate-shaped circuit body having a plurality of connection conductors corresponding to the plurality of bus bars, the circuit body having a trunk portion extending along a first direction in which the plurality of battery cells are arranged, and a plurality of branch portions branching from the trunk portion and connected to the bus bars, the plurality of branch portions including connecting branch portions connected to two of the bus bars, the two bus bars being a first bus bar and a second bus bar adjacent to each other in the first direction. The battery cell includes two bus bars, and the connecting branch portion has a first fixed portion fixed to the first bus bar, a second fixed portion fixed to the second bus bar, a first extension portion, and a second extension portion, wherein the first extension portion extends along the first direction between the main line portion and the first fixed portion, the second extension portion extends along the first direction between the first fixed portion and the second fixed portion, and the second extension portion has a length that is capable of fixing the first bus bar and the second bus bar to the battery cell while flexibly deforming the second extension portion. Effect of the Invention

[0007] The circuit body of the busbar module according to the present invention has a connecting branch portion connected to two bus bars. The connecting branch portion has a first fixing portion fixed to the first bus bar, a second fixing portion fixed to the second bus bar, a first extension portion, and a second extension portion. The second extension portion has a length that allows the first bus bar and the second bus bar to be fixed to the battery cell while flexibly deforming the second extension portion. The connecting branch portion can, for example, ensure the followability of the bus bar to the battery cell while avoiding interference between other components and the branch portion. The busbar module according to the present invention has an effect of improving design freedom. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a perspective view showing a schematic configuration of a battery pack according to an embodiment. [Diagram 2] FIG. 2 is an exploded perspective view of the bus bar module according to the embodiment. [Diagram 3] FIG. 3 is a perspective view of the bus bar according to the embodiment. [Figure 4] FIG. 4 is an enlarged view of a connecting branch portion according to the embodiment. [Diagram 5] FIG. 5 is a perspective view showing the connecting branch before being housed in the case. [Figure 6] FIG. 6 is a plan view showing the connecting branch portion housed in the case. [Figure 7] FIG. 7 is a cross-sectional perspective view showing the connecting branch portion housed in the case. [Figure 8] FIG. 8 is a perspective view of a parallel branch portion according to the embodiment. [Figure 9] FIG. 9 is a plan view of a parallel branch portion according to the embodiment. [Figure 10] FIG. 10 is a perspective view of a parallel branch portion according to the embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, a busbar module according to an embodiment of the present invention will be described in detail with reference to the drawings. Note that the present invention is not limited to the embodiment. Furthermore, components in the following embodiments include those that can be easily imagined by a person skilled in the art or those that are substantially the same.

[0010] [Embodiment] An embodiment will be described with reference to Figs. 1 to 10. The embodiment relates to a busbar module. Fig. 1 is a perspective view showing a schematic configuration of a battery pack according to an embodiment, Fig. 2 is an exploded perspective view of a busbar module according to an embodiment, Fig. 3 is a perspective view of a busbar according to an embodiment, Fig. 4 is an enlarged view of a connecting branch part according to an embodiment, Fig. 5 is a perspective view of a connecting branch part before being accommodated in a case, Fig. 6 is a plan view of a connecting branch part accommodated in a case, Fig. 7 is a cross-sectional perspective view of a connecting branch part accommodated in a case, Fig. 8 is a perspective view of a parallel branch part according to an embodiment, Fig. 9 is a plan view of a parallel branch part according to an embodiment, and Fig. 10 is a perspective view of a parallel branch part according to an embodiment. Fig. 7 shows a cross section taken along line VII-VII of Fig. 6.

[0011] 1, a battery pack 100 of this embodiment has a busbar module 1 and a battery module 110. The battery pack 100 is mounted as a power source in a vehicle such as an electric vehicle (EV), a hybrid electric vehicle (HEV), or a plug-in hybrid electric vehicle (PHEV). The battery pack 100 may have a plurality of busbar modules 1 and a plurality of battery modules 110.

[0012] The battery module 110 has a plurality of battery cells 120. The illustrated battery cells 120 have a rectangular parallelepiped shape. Two electrodes 121 are disposed on a first surface 120a of the battery cell 120. The shape of the first surface 120a is approximately rectangular.

[0013] The battery cells 120 are arranged along a first direction X. More specifically, the battery cells 120 are arranged such that a long side of a first surface 120a faces a long side of another adjacent first surface 120a in the first direction X. In the following description, a direction perpendicular to the first direction X in the first surface 120a is referred to as a "second direction Y". The second direction Y is the longitudinal direction of the first surface 120a. A direction perpendicular to both the first direction X and the second direction Y is referred to as a "third direction Z". The third direction Z is a height direction of the battery cells 120. The first surface 120a is perpendicular to the third direction Z. The battery pack 100 is mounted on a vehicle, for example, such that the first surface 120a faces upward in the vehicle vertical direction.

[0014] The two electrodes 121 on the first surface 120a are arranged side by side in the second direction Y. One of the two electrodes 121 on the first surface 120a is a positive electrode, and the other is a negative electrode. A group of the electrodes 121 arranged at one end in the longitudinal direction of the first surface 120a is referred to as a "first electrode group 121a". A group of the electrodes 121 arranged at the other end in the longitudinal direction of the first surface 120a is referred to as a "second electrode group 121b". In the battery module 110 of this embodiment, the positive electrodes and the negative electrodes are arranged alternately in the first electrode group 121a. In addition, the positive electrodes and the negative electrodes are arranged alternately in the second electrode group 121b. The busbar module 1 of this embodiment connects a plurality of battery cells 120 in series.

[0015] The busbar module 1 has a plurality of busbars 2, a plate-shaped circuit body 3, a case 4, and a cover 5. The busbars 2 are formed from a conductive metal plate such as copper or aluminum. As shown in FIG. 2, the busbar module 1 has a first busbar group 2A and a second busbar group 2B. The first busbar group 2A and the second busbar group 2B have a plurality of busbars 2 arranged along a first direction X. The busbars 2 of the first busbar group 2A are fixed to the first electrode group 121a of the battery module 110. The busbars 2 of the second busbar group 2B are fixed to the second electrode group 121b.

[0016] As shown in Fig. 3, the busbar 2 of this embodiment has a main body 21 and a frame portion 22. The main body 21 is a portion that is fixed to the electrode 121, and has a flat plate shape. The main body 21 is provided with one or two through holes 21a. The busbar 2 having two through holes 21a is fixed to two electrodes 121 and electrically connects the two electrodes 121. The busbar 2 having one through hole 21a is fixed to one electrode 121. The busbar 2 having one through hole 21a is arranged at the end in the first direction X.

[0017] The frame portion 22 is continuous with the main body 21 and protrudes from a side surface of the main body 21 along the second direction Y. The frame portion 22 is a portion that is fixed to the branch portion 31 of the circuit body 3. The illustrated frame portion 22 is formed in a rectangular frame shape.

[0018] The circuit body 3 is a plate-like circuit body and has flexibility. The circuit body 3 of this embodiment is a flexible printed circuit board (FPC: Flexible Printed Circuits). The circuit body 3 has a plurality of connection conductors 6 (see FIG. 4) corresponding to the plurality of bus bars 2. The circuit body 3 of this embodiment further has a connection conductor 6 corresponding to the thermistor 8. As shown in FIG. 2, the circuit body 3 has a trunk portion 30 and a plurality of branch portions 31. The trunk portion 30 and the branch portions 31 are integrally formed.

[0019] The trunk portion 30 has a flat plate shape and extends along the first direction X. That is, the longitudinal direction of the trunk portion 30 is the first direction X. The trunk portion 30 has a first side 30a and a second side 30b along the first direction X. The first side 30a is an edge portion of one end of the trunk portion 30 in the second direction Y. The second side 30b is an edge portion of the other end of the trunk portion 30 in the second direction Y. The branch portions 31 branch off from the trunk portion 30. The illustrated circuit body 3 has a plurality of branch portions 31 branching off from the first side 30a and a plurality of branch portions 31 branching off from the second side 30b. The branch portions 31 branching off from the first side 30a are connected to the busbars 2 of the first busbar group 2A. The branch portions 31 branching off from the second side 30b are connected to the busbars 2 of the second busbar group 2B.

[0020] The case 4 and the cover 5 constitute a housing that houses the circuit body 3 and the multiple bus bars 2. The case 4 and the cover 5 are molded, for example, from an insulating synthetic resin. The case 4 has multiple housing portions 41 that house the bus bars 2, and multiple support portions 42 that support the circuit body 3. The multiple housing portions 41 are aligned along the first direction X. Each housing portion 41 houses one bus bar 2. The support portions 42 extend along the second direction Y and support the trunk portion 30 of the circuit body 3 from below. The illustrated case 4 has a substantially rectangular shape in a plan view.

[0021] The cover 5 covers the circuit body 3 and accommodates the trunk portion 30 of the circuit body 3 between the case 4 and the cover 5. The illustrated cover 5 has a substantially rectangular flat plate shape in a plan view. The cover 5 has an engagement portion 51 that engages with the case 4, and is fixed to the case 4.

[0022] The multiple branch portions 31 of this embodiment have connecting branch portions 32. The connecting branch portion 32 is connected to two bus bars 2. The two bus bars 2 connected to the connecting branch portion 32 have a first bus bar 23 and a second bus bar 24. The first bus bar 23 and the second bus bar 24 are adjacent to each other in the first direction X. The bus bar module 1 of this embodiment has multiple connecting branch portions 32.

[0023] Fig. 4 is an enlarged perspective view of one connecting branch portion 32 surrounded by a dashed line in Fig. 2. The connecting branch portion 32 has a base portion 33, a first extending portion 34, a first fixing portion 35, a second extending portion 36, a second fixing portion 37, and a third extending portion 38.

[0024] The base 33 is connected to the trunk 30 and extends from the trunk 30 along the second direction Y. The first fixing portion 35 is fixed to the first bus bar 23. The second fixing portion 37 is fixed to the second bus bar 24. The first extending portion 34 extends along the first direction X between the base 33 and the first fixing portion 35. The second extending portion 36 extends along the first direction X between the first fixing portion 35 and the second fixing portion 37. The third extending portion 38 extends from the second fixing portion 37 along the first direction X. In the connecting branch portion 32 shown in FIG. 4, the first extending portion 34, the first fixing portion 35, the second extending portion 36, the second fixing portion 37, and the third extending portion 38 are linearly arranged in this order.

[0025] A plurality of connection conductors 6 are arranged on the connecting branch portion 32. The connection conductors 6 are made of a conductive metal such as copper, for example, a metal foil. The connection conductors 6 are sandwiched between two flexible insulating resin layers. The connection conductors 6 are connected to, for example, a control device that monitors the battery pack 100.

[0026] The multiple connection conductors 6 of the connecting branch portion 32 include a first conductor 61, a second conductor 62, and a third conductor 63. The first conductor 61 is routed from the trunk portion 30 to the first fixing portion 35, and is connected to the first bus bar 23. The second conductor 62 is routed from the trunk portion 30 to the second fixing portion 37, and is connected to the second bus bar 24. The first conductor 61 and the second conductor 62 are detection lines used to detect the voltage of the battery cell 120. The third conductor 63 is routed from the trunk portion 30 to the tip of the third extension portion 38, and is connected to the thermistor 8. The thermistor 8 is installed on the first surface 120a of the battery cell 120, and detects the temperature of the battery cell 120. The third conductor 63 is a detection line used to detect the temperature of the battery cell 120.

[0027] FIG. 5 shows the busbar module 1 before the busbar 2 is accommodated in the case 4. That is, FIG. 5 shows the shape of the branch portion 31 before the busbar 2 is accommodated in the case 4. The connecting branch portion 32 extends linearly along the trunk portion 30. The frame portion 22 of the first busbar 23 is fixed to the first fixing portion 35. More specifically, a pad formed of a metal foil is exposed in the first fixing portion 35. The frame portion 22 of the first busbar 23 is connected to the pad of the first fixing portion 35 by, for example, solder. The fuse 7 shown in FIG. 4 is interposed between this pad and the first conductor 61. That is, the first conductor 61 is connected to the first busbar 23 via the fuse 7.

[0028] The frame portion 22 of the second bus bar 24 is fixed to the second fixed portion 37. A pad is exposed at the second fixed portion 37. The frame portion 22 of the second bus bar 24 is connected to the pad of the second fixed portion 37 by, for example, soldering. The fuse 7 is interposed between this pad and the second conductor 62. That is, the second conductor 62 is connected to the second bus bar 24 via the fuse 7. The third conductor 63 is connected to the thermistor 8 at the tip of the third extension portion 38.

[0029] The second extension portion 36 has a length L1. The length L1 is the length along the first direction X, and is the length of the second extension portion 36 in an unbent state. The length L1 is determined so that the second extension portion 36 can flexibly deform in the third direction Z in a state in which the first bus bar 23 and the second bus bar 24 are fixed to the battery cell 120.

[0030] 6 shows an enlarged view of the connecting branch portion 32 accommodated in the case 4. The bus bar 2 is inserted into the corresponding accommodation portion 41 and is held by the accommodation portion 41. A locking portion 43 that locks the bus bar 2 is disposed in the accommodation portion 41. The locking portion 43 is provided on a side wall of the accommodation portion 41 and protrudes toward the internal space of the accommodation portion 41. The locking portion 43 holds the bus bar 2 between the bottom surface of the accommodation portion 41 and the locking portion 43.

[0031] The case 4 is configured so that the bus bar 2 can follow the movement of the battery cells 120 and the tolerance of the battery cells 120. For example, the locking portion 43 is arranged so that the bus bar 2 can move within a certain range in the third direction Z. The case 4 also has a connecting portion 44 that connects two adjacent storage portions 41. The connecting portion 44 has a curved shape and is elastically deformable. The connecting portion 44 allows relative movement of the storage portions 41 along, for example, the first direction X or the second direction Y.

[0032] FIG. 7 shows a perspective view of the connecting branch portion 32 arranged in the case 4. As shown in FIG. 7, the bus bar 2 is held at a position shifted in the third direction Z with respect to the trunk portion 30 of the circuit body 3. The case 4 holds the bus bar 2 at a position closer to the battery cell 120 with respect to the trunk portion 30. The first extension portion 34 of the connecting branch portion 32 is curved in a substantially S-shape when viewed from the second direction Y. In other words, the case 4 holds the first bus bar 23 such that the first extension portion 34 is curved in an S-shape. Therefore, the first bus bar 23 is fixed to the corresponding battery cell 120 by bending the first extension portion 34 in an S-shape.

[0033] The second extension portion 36 is flexibly deformed in a state where the connecting branch portion 32 is disposed in the case 4. More specifically, the second extension portion 36 is curved toward the trunk portion 30 side relative to the first fixing portion 35 and the second fixing portion 37. That is, the case 4 holds the first bus bar 23 and the second bus bar 24 so as to curve the second extension portion 36 toward the side opposite to the battery cell 120 side. In addition, the second extension portion 36 has a length that allows the first bus bar 23 and the second bus bar 24 to flexibly deform in a state where they are held in the case 4. Therefore, the first bus bar 23 and the second bus bar 24 can be fixed to the battery cell 120 while the second extension portion 36 is flexibly deformed.

[0034] The third extension portion 38 is curved in a substantially S-shape when viewed from the second direction Y. The thermistor 8 is located on the opposite side to the main line portion 30 with respect to the first fixed portion 35 and the second fixed portion 37. Thus, the third extension portion 38 is curved so as to approach the battery cell 120 toward the tip of the third extension portion 38. The thermistor 8 is held by the case 4 so as to be in contact with the first surface 120a of the battery cell 120.

[0035] The busbar module 1 of the present embodiment can make the busbar 2 appropriately follow the battery cell 120. As shown in FIG. 4, the first extension portion 34 is curved in a substantially S-shape. This allows the first busbar 23 to appropriately follow the corresponding battery cell 120. For example, the first extension portion 34 can allow the first busbar 23 to follow the corresponding battery cell 120 in any of the first direction X, the second direction Y, and the third direction Z. When the first busbar 23 is attached to the electrode 121 of the battery module 110, a worker can easily position the first busbar 23 on the corresponding battery cell 120. In addition, when the battery cell 120 moves relative to the trunk portion 30 due to thermal expansion or the like, the first extension portion 34 allows the first busbar 23 to follow the corresponding battery cell 120.

[0036] The second extension portion 36 is curved between the first fixing portion 35 and the second fixing portion 37. Therefore, it is possible for the first bus bar 23 and the second bus bar 24 to appropriately follow the corresponding battery cell 120. For example, the second extension portion 36 can allow the first bus bar 23 and the second bus bar 24 to follow the corresponding battery cell 120 in any of the first direction X, the second direction Y, and the third direction Z. When the first bus bar 23 and the second bus bar 24 are assembled to the electrode 121 of the battery module 110, an operator can easily position the first bus bar 23 and the second bus bar 24 on the corresponding battery cell 120. In addition, when the battery cell 120 moves relative to the trunk portion 30 due to thermal expansion or the like, the second extension portion 36 allows the first bus bar 23 and the second bus bar 24 to follow the corresponding battery cell 120.

[0037] Furthermore, according to this embodiment, the degree of freedom in designing the busbar module 1 is improved. For example, in the busbar module 1 of this embodiment, the thermistor 8 is aligned with the frame portions 22 of the first busbar 23 and the second busbar 24. The two frame portions 22 and the thermistor 8 are aligned linearly along the first direction X. The thermistor 8 is located between the main body 21 and the trunk portion 30 of the second busbar 24. That is, the thermistor 8 is adjacent to the main body 21 of the second busbar 24 in the second direction Y.

[0038] The frame portion 22 of the second bus bar 24 is shifted toward the first bus bar 23 with respect to the main body 21 so as not to interfere with the thermistor 8. In such an arrangement, even if an attempt is made to provide one branch portion 31 independently for the second bus bar 24, it may not be possible to ensure a branch portion 31 of sufficient length.

[0039] In the bus bar module 1 of the present embodiment, a single connecting branch portion 32 is connected to the first bus bar 23 and the second bus bar 24, thereby improving the degree of freedom in arranging the thermistor 8 and the frame portion 22. The connecting branch portion 32 ensures the followability of the first bus bar 23 and the second bus bar 24 to the battery cell 120 while avoiding interference between the thermistor 8 and the connecting branch portion 32. The illustrated connecting branch portion 32 also has a third extension portion 38 connected to the thermistor 8. This wiring structure simplifies the circuit body 3 compared to a case in which an independent branch portion 31 is provided for the thermistor 8.

[0040] Fig. 8 shows another connecting branch portion 32. The connecting branch portion 32 shown in Fig. 8 has a substantially U-shape or J-shape when viewed in a plane. This connecting branch portion 32 is a parallel branch portion 32P in which a first extending portion 34 and a second extending portion 36 are arranged in parallel. In the parallel branch portion 32P, the first extending portion 34 and the second extending portion 36 are arranged in the second direction Y.

[0041] In the parallel branch portion 32P, the first extension portion 34 and the second extension portion 36 extend in opposite directions. The first extension portion 34 extends from the base portion 33 to the first fixed portion 35 toward the first side X1. The second extension portion 36 extends from the first fixed portion 35 to the second fixed portion 37 toward the second side X2. The second side X2 is opposite to the first side X1. Note that the first side X1 and the second side X2 are not fixed. That is, in the first direction X, the side on which the first extension portion 34 is located with respect to the base portion 33 is the first side X1.

[0042] The parallel branch portion 32P shown in Fig. 8 has a third extension portion 38. The third extension portion 38 extends from the second fixed portion 37 toward the second side X2, and is connected to the thermistor 8. The thermistor 8 is disposed linearly with respect to the frame portions 22 of the first bus bar 23 and the second bus bar 24. Compared to such an arrangement of the thermistor 8, the parallel branch portion 32P shown in Fig. 8 can improve the design freedom of the circuit body 3, as will be described below.

[0043] 9, the arrangement of the branch portion 31 when an independent branch portion 31 is to be provided for the second bus bar 24 is shown by a dashed line. The independent branch portion 31 corresponding to the second bus bar 24 interferes with the thermistor 8. The parallel branch portion 32P shown in FIG. 8 can connect the first bus bar 23 and the second bus bar 24 to the trunk portion 30 while avoiding interference with the thermistor 8.

[0044] FIG. 10 shows another parallel branch 32P. The parallel branch 32P shown in FIG. 10 is connected to the end 30c of the trunk 30 in the first direction X. The parallel branch 32P in FIG. 10 has a first extension 34 and a second extension 36 arranged in parallel, similar to the parallel branch 32P in FIG. 8. The first extension 34 extends from the base 33 to the first fixing portion 35 toward the first side X1. The first extension 34 extends toward the side away from the end 30c. The second extension 36 extends from the first fixing portion 35 to the second fixing portion 37 toward the second side X2. The second bus bar 24 is held such that the frame 22 is located on the second side X2 with respect to the end 30c of the trunk 30.

[0045] 10, the circuit body 3 needs to have an extension 30x indicated by a dashed line. That is, the end 30c of the circuit body 3 needs to be extended to the second side X2. In the busbar module 1 of the present embodiment, the parallel branch 32P is provided in the circuit body 3, so that the overall length of the circuit body 3 can be shortened.

[0046] In this embodiment, the multiple branch portions 31 include a single branch portion 31. The single branch portion 31 is connected to one busbar 2. In other words, the busbar module 1 of this embodiment includes a single branch portion 31, a straight-shaped connecting branch portion 32, and a parallel branch portion 32P. The combination of these branches 31, 32, 32P improves the design freedom and wiring freedom of the circuit body 3.

[0047] As described above, the busbar module 1 of this embodiment has a plurality of bus bars 2 and a flexible, plate-shaped circuit body 3. The multiple bus bars 2 are fixed to the battery cells 120 of the battery module 110. The circuit body 3 has a plurality of connection conductors 6 corresponding to the multiple bus bars 2. The circuit body 3 has a trunk portion 30 and a plurality of branch portions 31. The trunk portion 30 extends along the first direction X in which the multiple battery cells 120 are arranged. The branch portions 31 branch off from the trunk portion 30 and are connected to the bus bars 2.

[0048] The multiple branches 31 include a connecting branch portion 32 connected to the two bus bars 2. The two bus bars 2 include a first bus bar 23 and a second bus bar 24 adjacent to each other in the first direction X. The connecting branch portion 32 has a first fixing portion 35 fixed to the first bus bar 23, a second fixing portion 37 fixed to the second bus bar 24, a first extending portion 34, and a second extending portion 36. The first extending portion 34 extends along the first direction X between the trunk portion 30 and the first fixing portion 35. The second extending portion 36 extends along the first direction X between the first fixing portion 35 and the second fixing portion 37.

[0049] The second extension portion 36 has a length L1. The length L1 is a length that allows the first bus bar 23 and the second bus bar 24 to be fixed to the battery cell 120 while flexibly deforming the second extension portion 36. According to the bus bar module 1 of the present embodiment, it is possible to improve the degree of freedom in designing the bus bar module 1. For example, it is possible to ensure the ability of the bus bar 2 to follow the battery cell 120 while avoiding interference between the branch portion 31 and other components such as the thermistor 8. For example, it is possible to reduce the number of branch portions 31 required relative to the number of bus bars 2, and the degree of freedom in designing the circuit body 3 is improved.

[0050] In the present embodiment, the first bus bar 23 and the second bus bar 24 are fixed to the battery cell 120 by bending the first extension portion 34 into an S shape and bending the second extension portion 36 toward the side opposite the battery cell 120. Such a curved shape ensures the ability of the bus bar 2 to follow the battery cell 120.

[0051] The busbar module 1 of the present embodiment has a parallel branch portion 32P as the connecting branch portion 32. The parallel branch portion 32P is a connecting branch portion 32 in which a first extension portion 34 and a second extension portion 36 are arranged in parallel. The parallel branch portion 32P has a base portion 33 connected to the trunk portion 30. The first extension portion 34 of the parallel branch portion 32P extends from the base portion 33 to the first fixing portion 35 toward a first side X1 along the first direction X. The second extension portion 36 of the parallel branch portion 32P extends from the first fixing portion 35 to the second fixing portion 37 toward a second side X2 opposite to the first side X1. The parallel branch portion 32P improves the degree of freedom of design to avoid interference between the branch portion 31 and other components. In addition, the parallel branch portion 32P is effective in miniaturizing the circuit body 3 in the first direction X.

[0052] The first extension portion 34 does not have to be curved in an S-shape. For example, in the connecting branch portion 32 attached to the battery module 110, the base portion 33 and the first fixing portion 35 may be at substantially the same position in the third direction Z. In this case, the first extension portion 34 may extend in a substantially straight line from the base portion 33 to the first fixing portion 35. The first extension portion 34 may be curved toward the third direction Z like the second extension portion 36.

[0053] The connecting branch portion 32 may be connected to three or more bus bars 2. For example, in the connecting branch portion 32 shown in FIG. 5, the tip of the third extension portion 38 may be connected to the third bus bar instead of the thermistor 8. In this case, the connecting branch portion 32 may have a third fixed portion that is fixed to the third bus bar. For example, in the parallel branch portion 32P shown in FIG. 8, the tip of the third extension portion 38 may be connected to the adjacent bus bar 2 instead of the thermistor 8.

[0054] The contents disclosed in the above embodiments can be implemented in appropriate combinations. [Explanation of symbols]

[0055] 1 Busbar module 2: bus bar, 2A: first bus bar group, 2B: second bus bar group 3: circuit body, 4: case, 5: cover, 6: connecting conductor, 7: fuse 8: Thermistor 21: Main body, 21a: Through hole 22: frame portion, 23: first bus bar, 24: second bus bar 30: trunk portion, 30a: first side, 30b: second side, 30c: end portion 31: Branch, 32: Connected branch, 32P: Parallel branch 33: Base, 34: First extension part, 35: First fixed part, 36: Second extension part 37: Second fixed part, 38: Third extension part 41: Storage portion, 42: Support portion, 43: Locking portion, 44: Connection portion 51: Engagement part 61: first conductor, 62: second conductor, 63: third conductor 100: battery pack, 110: battery module 120: battery cell, 120a: first surface 121: Electrode, 121a: First electrode group, 121b: Second electrode group X: first direction, Y: second direction, Z: third direction

Claims

1. a battery module including a plurality of battery cells; and a plurality of bus bars fixed to the battery cells. a plate-like flexible circuit body having a plurality of connection conductors corresponding to the plurality of bus bars; Equipped with the circuit body includes a trunk portion extending along a first direction in which the plurality of battery cells are arranged, and a plurality of branch portions branching from the trunk portion and connected to the bus bar, the plurality of branch portions include connecting branch portions connected to two of the bus bars, The two bus bars include a first bus bar and a second bus bar adjacent to each other in the first direction, the connecting branch portion has a first fixed portion fixed to the first bus bar, a second fixed portion fixed to the second bus bar, a first extending portion, and a second extending portion, The first extension portion extends along the first direction between the trunk portion and the first fixed portion, The second extension portion extends along the first direction between the first fixed portion and the second fixed portion, The second extension portion has a length that allows the first bus bar and the second bus bar to be fixed to the battery cell while the second extension portion is flexibly deformed. A busbar module comprising:

2. The first bus bar and the second bus bar are fixed to the battery cell by bending the first extension portion in an S shape and bending the second extension portion toward the side opposite to the battery cell. The busbar module according to claim 1 .

3. The connecting branch portion includes a parallel branch portion in which the first extending portion and the second extending portion are parallel to each other, The parallel branch portion has a base portion connected to the trunk portion, The first extension portion of the parallel branch portion extends from the base portion to the first fixing portion toward a first side along the first direction, The second extension portion of the parallel branch portion extends from the first fixing portion to the second fixing portion toward a second side opposite to the first side. The busbar module according to claim 1 .

Images