Busbar Module

Abstract

To provide a bus bar module which is advantageous in reducing the height of a housing part for housing a bus bar.SOLUTION: A bus bar module 1 comprises: a bus bar 10 for connecting one terminal of a first unit cell 100a to one terminal of a second unit cell 100b, the terminals protruding in parallel to each other; and an insulative bus bar case 20 having a housing part 30 which houses the bus bar 10, and a cover 40 which is fitted to the housing part 30. The housing part 30 has: a frame-like side wall part 31 which surrounds the bus bar 10 from a direction perpendicular to a connection direction of the terminals; and a support part 32 which supports the bus bar 10 from a first opening 21 side, of the side wall part 31, which faces the first unit cell 100a or the second unit cell 100b. The cover 40 has: a cover body 41 which covers a second opening 22, of the side wall part 31, which is opposite to the first opening 21; and a protruding part 42 which protrudes from the cover body 41 toward the first opening 21 so as to come into contact with the bus bar 10.SELECTED DRAWING: Figure 1A

Description

[Technical Field]

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

[0002] Conventionally, vehicles such as electric vehicles or hybrid vehicles are equipped with battery packs as a power source. Battery packs sometimes employ bus bar modules that electrically connect the individual cells contained therein. Patent Document 1, which describes technology related to bus bar modules, discloses a battery connection assembly that connects the individual cells in a battery module that includes multiple cells. The battery connection assembly includes a bus bar that electrically connects the positive terminal of one of adjacent cells to the negative terminal of the other cell, and an insulating member that holds the bus bar internally.

[0003] The insulating member disclosed in Patent Document 1 has a side wall of an accommodating section that accommodates a bus bar, and the side wall has a locking claw that protrudes into the accommodating section and is elastically deformable in the thickness direction of the side wall. When the bus bar is attached to the accommodating section, the locking claw elastically deforms as the bus bar abuts against it, and then the bus bar moves over it and returns to its original shape. Finally, a portion of the bus bar is placed on the mounting section, and the edge of the bus bar engages with the locking claw, thereby holding the bus bar in the accommodating section. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-227004 Summary of the Invention [Problem to be solved by the invention]

[0005] In the insulating member disclosed in Patent Document 1, the locking claws need to have a certain length along the mounting direction to allow for the elastic deformation required for attaching the bus bar. Therefore, the height of the side wall along the mounting direction of the bus bar needs to be sufficient to ensure the length of the locking claws, which hinders the height of the housing portion, which is part of the insulating portion, and as a result, can hinder the miniaturization of the battery connection assembly.

[0006] The present invention has been made in view of the problems inherent in the conventional technology, and an object of the present invention is to provide a bus bar module that is advantageous in reducing the height of a housing portion that houses a bus bar. [Means for solving the problem]

[0007] One aspect of the present invention is a busbar module that electrically connects a first cell and a second cell, each having a pair of terminals, a positive terminal and a negative terminal. The busbar module includes: a busbar that connects one terminal of the first cell and one terminal of the second cell, which protrude in parallel to each other; and an insulating busbar case having an accommodation portion that accommodates the busbar and a cover that is attached to the accommodation portion. The accommodation portion has a frame-shaped side wall portion that surrounds the busbar in a direction perpendicular to the connection direction of the terminals, and a support portion that supports the busbar from the side of the side wall portion with a first opening that faces the first cell or the second cell. The cover has a cover main body that covers a second opening on the side wall portion opposite the first opening, and a protrusion that protrudes from the cover main body toward the first opening and makes contact with the busbar. [Effects of the Invention]

[0008] According to the present invention, it is possible to provide a bus bar module that is advantageous in reducing the height of the housing portion that houses the bus bar. [Brief explanation of the drawings]

[0009] [Figure 1A] FIG. 2 is a perspective view of a bus bar module according to an embodiment before a cover is attached. [Figure 1B] FIG. 2 is a perspective view of the bus bar module according to the embodiment after the cover is attached. [Figure 2] FIG. 2 is a perspective view showing a first example of a bus bar case. [Figure 3] FIG. 10 is a perspective view showing a second example of a bus bar case. [Figure 4] FIG. 10 is a perspective view showing a third example of a bus bar case. [Figure 5] FIG. 10 is a perspective view showing a fourth example of a bus bar case. DETAILED DESCRIPTION OF THE INVENTION

[0010] A bus bar module according to an embodiment will be described in detail below with reference to the drawings. Note that the dimensional proportions in the drawings are exaggerated for the sake of convenience and may differ from the actual proportions.

[0011] 1A and 1B are perspective views of a busbar module 1 according to one embodiment. FIG. 1A shows the busbar module 1 in a state before a cover 40 is attached to the accommodating portion 30 in a busbar case 20. FIG. 1B shows the busbar module 1 in a state after the cover 40 has been attached to the accommodating portion 30. Hereinafter, the state in which the cover 40 is attached to the accommodating portion 30 will be simply referred to as "when the cover is attached."

[0012] Generally, vehicles such as electric vehicles or hybrid vehicles are equipped with a battery pack having a plurality of electric cells 100 as a driving source. The busbar module 1 is used in such a battery pack to electrically connect the electric cells 100 to each other. The battery pack may also be called a battery pack. The electric cells may also be called single cells or cells.

[0013] Hereinafter, as an example, the busbar module 1 electrically connects two cells 100, a first cell 100a and a second cell 100b, included in a virtual battery pack, as shown by the two-dot chain lines in FIGS. 1A and 1B. The first cell 100a and the second cell 100b are assumed to have the same shape and configuration. The cell 100 has a rough rectangular parallelepiped shape. One end face of the cell 100 is provided with a positive terminal 101 and a negative terminal 102 that are spaced apart and protrude in the same direction. The positive terminal 101 and the negative terminal 102 are each round rod-shaped, and at least the tip end is formed with a screw thread.

[0014] Furthermore, with reference to the shape or structure of the cell 100, each direction is defined as follows: The Z direction is along the protruding direction of the positive electrode terminal 101 and the negative electrode terminal 102. The X direction and the Y direction are perpendicular to the Z direction and perpendicular to each other. The X direction is along the arranging direction of the positive electrode terminal 101 and the negative electrode terminal 102 in one cell 100. The cell 100 can be regarded as a flattened rectangular parallelepiped with the XZ plane as its main plane and the Y direction as its thickness direction. Hereinafter, of the four end faces of the cell 100, the end face parallel to the XY plane and on which the positive electrode terminal 101 and the negative electrode terminal 102 are provided is defined as the connection surface 103. On the connection surface 103, the positive electrode terminal 101 is provided in one end region in the X direction, and the negative electrode terminal 102 is provided in the other end region in the X direction. The Y direction corresponds to the arrangement direction of the cells 100 in the battery pack. In this embodiment, the first cell 100a and the second cell 100b are arranged such that the positive electrode terminal 101 and the negative electrode terminal 102 are opposite in the X direction. In this case, the positive electrode terminal 101 of the first cell 100a and the negative electrode terminal 102 of the second cell 100b, and the negative electrode terminal 102 of the first cell 100a and the positive electrode terminal 101 of the second cell 100b (not shown) are closely opposed to each other along the Y direction.

[0015] The busbar module 1 electrically connects the positive terminal 101 of the first cell 100a and the negative terminal 102 of the second cell 100b, thereby connecting the first cell 100a and the second cell 100b in series. The busbar module 1 includes a busbar 10, a busbar case 20, and a voltage detection circuit (not shown).

[0016] The bus bar 10 is a conductive metal member that connects the positive terminal 101 of the first cell 100a and the negative terminal 102 of the second cell 100b, which protrude in parallel to each other. The bus bar 10 can be formed by pressing a long metal plate. In this embodiment, the bus bar 10 has a first connection portion 11, a second connection portion 12, and an engagement portion 13.

[0017] The first connection portion 11 is a plate-shaped portion that connects the positive terminal 101 of the first battery 100a. For example, the first connection portion 11 may have a first through hole 11a that penetrates in the thickness direction. When the busbar 10 is attached, a portion of the positive terminal 101 of the first battery 100a passes through the first through hole 11a. Similarly, the second connection portion 12 is a plate-shaped portion that connects the negative terminal 102 of the second battery 100b. For example, the second connection portion 12 may have a second through hole 12a that penetrates in the thickness direction. When the busbar 10 is attached, a portion of the negative terminal 102 of the second battery 100b passes through the second through hole 12a. In this embodiment, the busbar 10 is rectangular in shape with the longitudinal direction aligned in the Y direction when viewed in the Z direction. The thickness directions of the first connection portion 11 and the second connection portion 12 are aligned with the Z direction. Furthermore, the first through hole 11a and the second through hole 12a form a pair of through holes in one bus bar 10 and are spaced apart from each other in the Y direction.

[0018] The opening shapes of the first through hole 11a and the second through hole 12a may be circular to match the axial shapes of the positive electrode terminal 101 and the negative electrode terminal 102. In this case, the pitch between the axial centers of the first through hole 11a and the second through hole 12a roughly matches the pitch between the axial centers of the positive electrode terminal 101 of the first cell 100a and the negative electrode terminal 102 of the second cell 100b.

[0019] The engaging portion 13 is provided so as to cross between the first connecting portion 11 and the second connecting portion 12, and is supported by the supporting portion 32 of the busbar case 20. In this embodiment, the engaging portion 13 is provided in the middle of the busbar 10 in the Y direction, and is a bent portion having a convex shape that protrudes outward in the Z direction so that a groove 13a is formed on the inside along the X direction.

[0020] Fig. 2 is a perspective view showing a first example of the bus bar case 20. Fig. 2 shows the bus bar case 20 before the cover 40 is attached to the housing portion 30, similar to that shown in Fig. 1A.

[0021] The bus bar case 20 is an insulating member made of, for example, synthetic resin, and houses the bus bar 10 connected to the positive terminal 101 of the first cell 100a and the negative terminal 102 of the second cell 100b. The bus bar case 20 can be formed by injection molding using a mold. In this embodiment, the bus bar case 20 integrally includes the housing portion 30, the cover 40, and the hinge portion 50.

[0022] The accommodating portion 30 accommodates the bus bar 10. The accommodating portion 30 has a side wall portion 31, a support portion 32, and a locked portion 33.

[0023] The sidewall portion 31 has a frame shape that surrounds the busbar 10 in the X direction or Y direction perpendicular to the Z direction, which is the connection direction of the positive terminal 101 and the negative terminal 102. In this embodiment, the sidewall portion 31 is a rectangular frame whose outer and inner peripheries are rectangular, with the Y direction as viewed in the Z direction as the longitudinal direction, to match the rectangular shape of the busbar 10 as viewed in the Z direction. Specifically, the sidewall portion 31 has a first sidewall 31a, a second sidewall 31b, a third sidewall 31c, and a fourth sidewall 31d. The first sidewall 31a, the second sidewall 31b, the third sidewall 31c, and the fourth sidewall 31d are continuous in this order in an annular shape. The first sidewall 31a and the third sidewall 31c face each other in the X direction. The second sidewall 31b and the fourth sidewall 31d face each other in the Y direction. In this case, an accommodation space S is formed inside the side wall portion 31, penetrating along the Z direction.

[0024] Here, when the busbar module 1 is connected to the first cell 100a and the second cell 100b, the side facing the first cell 100a or the second cell 100b is defined as the "bottom," and the side opposite the bottom in the Z direction is defined as the "top." Hereinafter, in the side wall portion 31, the lower opening that communicates with the storage space S is referred to as the first opening 21, and the upper opening that communicates with the storage space S is referred to as the second opening 22.

[0025] The length dimensions in the Y direction of the first side wall 31a and the third side wall 31c and the length dimensions in the X direction of the second side wall 31b and the fourth side wall 31d are set so that the inner circumference of the side wall portion 31 is larger than the outer circumference of the busbar 10 when viewed in the Z direction. The height dimension in the Z direction of the side wall portion 31 is set so that it is higher than the upper ends of the positive electrode terminal 101 and the negative electrode terminal 102 when the busbar module 1 is connected to the first cell 100a and the second cell 100b.

[0026] The support portion 32 supports the bus bar 10 from the side of the first opening 21 within the accommodation space S. In this embodiment, the support portion 32 is a rod-shaped portion extending in the X direction so that one end is continuous with the first side wall 31a and the other end is continuous with the third side wall 31c. The support portion 32 is located near the first opening 21 in the Z direction and is located in the middle of the accommodation space S in the Y direction. The rod shape of the support portion 32 is not particularly limited, but is preferably a shape that can engage with the groove 13a of the engagement portion 13 provided on the bus bar 10.

[0027] The locked portion 33 is provided on the outer surface 31e of the side wall portion 31, and engages with the locking portion 43 when the cover is attached. In this embodiment, the locked portion 33 is provided on a part of the outer surface 31e of the third side wall 31c.

[0028] The cover 40 is attached to the housing portion 30. The cover 40 has a cover body 41, a protruding portion 42, and a locking portion 43.

[0029] The cover body 41 is a plate that covers the second opening 22 in the side wall portion 31. In this embodiment, since the side wall portion 31 is a rectangular frame, the shape of the cover body 41 when viewed in the Z direction is roughly the same as the opening shape of the second opening 22, but is a rectangle that is smaller than the size of the second opening 22. The cover body 41 has an outer surface 41a and an inner surface 41b, which are opposite each other. The outer surface 41a faces the outside when the cover is attached. The inner surface 41b faces the storage space S when the cover is attached. Furthermore, of the four edges of the cover body 41, one edge along the Y direction is defined as a first edge 41c, and the other edge along the Y direction is defined as a second edge 41d.

[0030] The protrusion 42 comes into contact with the busbar 10 in the accommodation space S when the cover is attached. The protrusion 42 is a columnar portion that protrudes in the normal direction from the inner surface 41b so that its axial direction when the cover is attached is along the Z direction. In other words, the protrusion 42 protrudes from the cover body 41 toward the first opening 21 when the cover is attached. Here, in the accommodation space S, the busbar 10 is connected to the positive terminal 101 of the first cell 100a and the negative terminal 102 of the second cell 100b. Therefore, the protrusion 42 comes into contact with the remaining surfaces of the surface of the busbar 10, avoiding the portion of the first connection portion 11 where the positive terminal 101 is bolted and the portion of the second connection portion 12 where the negative terminal 102 is bolted.

[0031] In this embodiment, as an example, there are a total of four protrusions 42: a first protrusion 42a, a second protrusion 42b, a third protrusion 42c, and a fourth protrusion 42d. The first protrusion 42a and the fourth protrusion 42d are aligned along the first edge 41c at a distance that allows them to avoid contact with the engaging portion 13 of the busbar 10 when the cover is attached. The second protrusion 42b and the third protrusion 42c are aligned along the second edge 41d at a distance that allows them to avoid contact with the engaging portion 13 of the busbar 10 when the cover is attached.

[0032] When the cover is attached, the first protrusion 42a and the second protrusion 42b are aligned in the X direction at a distance that allows them to avoid contact with the portion of the first connection part 11 where the positive electrode terminal 101 is bolted. In other words, when the cover is attached, the tip portions 42e of the first protrusion 42a and the second protrusion 42b press against the first connection surface 11b at different positions from each other, other than the portion of the first connection part 11 where the positive electrode terminal 101 is bolted.

[0033] When the cover is attached, the third protrusion 42c and the fourth protrusion 42d are aligned with each other in the X direction and at a distance that allows them to avoid contact with the portion of the second connection part 12 where the negative electrode terminal 102 is bolted. In other words, when the cover is attached, the tip portions 42e of the third protrusion 42c and the fourth protrusion 42d press against the second connection surface 12b at different positions from each other, other than the portion of the second connection part 12 where the negative electrode terminal 102 is bolted.

[0034] The shape of the tip 42e of each protrusion 42 may be curved, as shown in FIG. 2 and other figures, to easily accommodate deviations in the relative positions of the bus bar 10 and the bus bar case 20.

[0035] When the cover is attached, the locking portion 43 engages with a locked portion 33 that is provided in advance in the storage portion 30. In this embodiment, the locked portion 33 is provided on a part of the outer surface 31e of the third side wall 31c of the storage portion 30, and therefore the locking portion 43 is provided on a part of the first edge 41c of the cover body 41. The locked portion 33 and the locking portion 43 form a pair to constitute a locking mechanism, but the specific configuration is not particularly limited.

[0036] The hinge portion 50 is a deformable thin plate portion that connects the storage portion 30 and the cover 40. In this embodiment, before the cover 40 is attached to the storage portion 30, there are two hinge portions 50 that are arranged in parallel so as to extend along the X direction and be spaced apart from each other in the Y direction. One end of the hinge portion 50 is continuous with the outer surface 31e on the first side wall 31a of the side wall portion 31. The other end opposite to the one end of the hinge portion 50 is continuous with the second edge 41d of the cover main body 41. When the cover is attached, the hinge portion 50 is bent and the locking portion 43 is locked with the locked portion 33, so that the cover 40 is held in the storage portion 30 while covering the second opening 22.

[0037] Here, first side wall 31a may have two notches 31f, each facing second opening 22, that each accommodate a portion of bent hinge portion 50 when the cover is attached. In this case, one end of hinge portion 50 is continuous with the bottom of notch 31f. With this configuration, when the cover is attached, as shown in FIG. 1B, the entire cover main body 41 can be accommodated in storage space S so that outer surface 41a of cover main body 41 roughly aligns with the opening end of storage section 30 on the second opening 22 side.

[0038] The voltage detection circuit is a wiring material arranged within the busbar module 1, and is electrically connected to the positive terminal 101 and the negative terminal 102 of each of the cells 100 connected in series to each other by the busbar 10, and detects the voltage of each of the cells 100. The voltage detection circuit is connected to a controller (not shown), and transmits detection information to the controller, thereby controlling the state of each of the cells 100.

[0039] Next, the attachment of the bus bar module 1 to the cell 100 will be described.

[0040] 1A, the first cell 100a and the second cell 100b are assumed to be pre-arranged with the Y direction as the alignment direction. The worker inserts the positive terminal 101 of the first cell 100a and the negative terminal 102 of the second cell 100b into the accommodation space S through the first opening 21 of the accommodation portion 30, and places the side wall portion 31 on the connection surfaces 103 of the first cell 100a and the second cell 100b.

[0041] Next, the worker places the busbar 10 in the housing space S through the second opening 22 of the housing portion 30 so that the grooves 13a of the busbar 10 engage with the supports 32 of the housing portion 30. At this time, the worker passes the positive terminal 101 of the first cell 100a through the first through-hole 11a of the first connection portion 11 of the busbar 10. At the same time, the worker passes the negative terminal 102 of the second cell 100b through the second through-hole 12a of the second connection portion 12 of the busbar 10. Thereafter, the worker attaches the first connection portion 11 to the positive terminal 101 and the second connection portion 12 to the negative terminal 102 by fastening bolts using nuts or the like (not shown). FIG. 1A shows the external appearance of the busbar 10 and the busbar case 20 at this stage.

[0042] Then, the worker attaches the cover 40 to the housing portion 30 while bending the hinge portions 50 of the bus bar case 20. FIG. 1B shows the external appearance of the bus bar case 20 at this stage. The cover main body 41 is locked while covering the second opening 22 by engaging the locking portions 43 of the cover 40 with the locked portions 33 of the housing portion 30. At this time, the tip portions 42e of the multiple protrusions 42 protruding from the inner surface 41b of the cover main body 41 come into contact with the bus bar 10, so that each protrusion 42 presses the bus bar 10 toward the connection surface 103 of each cell 100. In this embodiment, the first protrusion 42a and the second protrusion 42b press against the first connection surface 11b of the first connection portion 11. Meanwhile, the third protrusion 42c and the fourth protrusion 42d press against the second connection surface 12b of the second connection portion 12.

[0043] Meanwhile, the busbar 10 is supported by the support portions 32 of the accommodating portion 30 in the direction opposite to the direction in which the first connection surface 11b and the second connection surface 12b are pressed against the respective protrusions 42. Therefore, the busbar 10 is held in the busbar case 20 in such a way that the busbar 10 is entirely sandwiched between the support portions 32 and the multiple protrusions 42 along the Z direction.

[0044] Here, the Z direction when the cover is attached is defined as the height direction of the busbar 10 and the busbar case 20. In this case, it is desirable to set the height dimension of each protrusion 42 to a level that can apply a pressing force sufficient to hold the busbar 10 when the outer surface 41a of the cover body 41 is aligned in the height direction with the opening end of the accommodating section 30 on the second opening 22 side when the cover is attached.

[0045] Next, the effects of the bus bar module 1 will be described.

[0046] First, the busbar module 1 electrically connects a first cell 100a and a second cell 100b, each having a pair of terminals, a positive terminal 101 and a negative terminal 102. The busbar module 1 includes a busbar 10 that connects one terminal of the first cell 100a and one terminal of the second cell 100b, which protrude in parallel to each other. The busbar module 1 also includes an insulating busbar case 20 that has a housing portion 30 that houses the busbar 10 and a cover 40 that is attached to the housing portion 30. The housing portion 30 has a frame-shaped sidewall portion 31 that surrounds the busbar 10 in a direction perpendicular to the terminal connection direction, and a support portion 32 that supports the busbar 10 from the side of the sidewall portion 31 facing the first cell 100a or the second cell 100b. The cover 40 has a cover body 41 that covers the second opening 22 on the opposite side of the side wall portion 31 from the first opening 21, and a protrusion 42 that protrudes from the cover body 41 toward the first opening 21 and comes into contact with the bus bar 10.

[0047] In the examples using the above-mentioned drawings, the connection direction in which the positive electrode terminal 101 and the negative electrode terminal 102 are connected to the bus bar 10 corresponds to the Z direction.

[0048] According to the configuration of the busbar module 1, the busbar 10 is connected to the first cell 100a and the second cell 100b while being entirely covered by the insulating busbar case 20. This protects the busbar 10 itself, or the connection portion between the busbar 10 and the positive terminal 101 or the negative terminal 102, from the outside. For example, it is possible to prevent a short circuit between the positive terminal 101 and the negative terminal 102 due to an operator accidentally touching the positive terminal 101 or the negative terminal 102 with a tool.

[0049] Furthermore, according to the configuration of the busbar module 1, the busbar case 20 holds the busbar 10 by sandwiching it between the support portion 32, which is a part of the accommodation portion 30, and the protrusion portion 42, which is a part of the cover 40, along the terminal connection direction. If the terminal connection direction is defined as the height direction, then in the busbar case 20, the height dimension of the protrusion portion 42 can be set as low as possible while taking into consideration the height of the terminals such as the positive terminal 101, thereby making it possible to set the height position of the cover 40 low. Therefore, the height of the side wall portion 31 to which the cover 40 is directly attached, i.e., the height of the accommodation portion 30, can be made even lower.

[0050] As a comparative example, consider a case where the busbar case does not have the protrusion 42 described above, but instead holds the busbar using locking claws provided on the side walls that constitute the housing. In this case, unlike the present embodiment, all of the busbar holding mechanisms are located in the housing. Furthermore, the locking claws must have a certain length along the mounting direction (i.e., the height direction) to accommodate the elastic deformation required for installing the busbar. The required length of the locking claws is independent of the height of the terminals, such as the positive terminal 101. Therefore, even if the height of the side walls can be set lower based on the height of the terminals, such as the positive terminal 101, the need to ensure the length of the locking claws may prevent the sidewalls from being set lower.

[0051] As described above, according to this embodiment, it is possible to provide a bus bar module 1 that is advantageous in reducing the height of the accommodation portion 30 that accommodates the bus bar 10.

[0052] Furthermore, according to this embodiment, the side wall 31 of the accommodation section 30 does not have any locking claws, as described in the comparative example above. Therefore, before the cover 40 is attached to the accommodation section 30, the accommodation space S inside the accommodation section 30 is wider by the amount corresponding to the absence of the locking claws, when viewed from above in the Z direction. Therefore, for example, it is possible to reduce in advance the number of areas that may interfere when connecting the positive terminal 101 or the negative terminal 102 to the first connection section 11 or the second connection section 12 of the bus bar 10 by bolting or the like.

[0053] In the above description with reference to the drawings, it has been assumed that the protrusions 42 include the first protrusion 42a, the second protrusion 42b, the third protrusion 42c, and the fourth protrusion 42d. Such multiple protrusions 42 allow the bus bar 10 to be sandwiched in a balanced manner with the support portion 32, thereby improving the reliability of holding the bus bar 10. However, depending on the size or detailed shape of the bus bar 10 or the bus bar case 20, or the associated protruding position of the protrusion 42 on the cover body 41, there may be cases where the bus bar case 20 is only required to have one protrusion 42.

[0054] In the above description, the positive electrode terminal 101 and the negative electrode terminal 102 are connected to the bus bar 10 by bolting using nuts or the like. However, this bolting is merely an example, and, for example, the positive electrode terminal 101 and other terminals may be connected to the bus bar 10 by laser welding or the like. The absence of locking claws on the side wall portion 31 allows the accommodation space S to be made larger before the cover is attached, which is also advantageous in that it reduces areas that may interfere when joining terminals such as the positive electrode terminal 101 to the bus bar 10 by laser welding.

[0055] On the other hand, the bus bar case 20 may be modified as follows.

[0056] Fig. 3 is a perspective view showing a second example of the bus bar case 20. With regard to the bus bar case 20 according to the second example, the same parts as those of the bus bar case 20 according to the first example shown in Fig. 2 are denoted by the same reference numerals, and description thereof will be omitted.

[0057] In the second example of the busbar case 20, the cover body 41 has a through hole 41e. Because the cover 40 has a protrusion 42 protruding from the cover body 41, the through hole 41e is formed in a region of the cover body 41 that avoids the location of the protrusion 42. In the example of this embodiment, the protrusions 42 include a first protrusion 42a, a second protrusion 42b, a third protrusion 42c, and a fourth protrusion 42d. In this case, the opening shape of the through hole 41e may be a rectangle with its longitudinal direction in the Y direction. Furthermore, the through hole 41e may be formed to cover any of the regions between the first protrusion 42a and the second protrusion 42b and between the third protrusion 42c and the fourth protrusion 42d. By having the through hole 41e have such a shape, the connection portion between the busbar 10 and a terminal such as the positive terminal 101 in the accommodation space S can be seen from the outside through the through hole 41e even when the cover is attached.

[0058] In this manner, in the bus bar module 1, the cover body 41 may have the through-hole 41e.

[0059] With this busbar module 1, even when the cover is attached, an operator can view the inside of the storage space S from the outside through the through hole 41e, and can perform, for example, bolting or laser welding to connect the busbar 10 to a terminal such as the positive terminal 101.

[0060] Fig. 4 is a perspective view showing a third example of the bus bar case 20. With regard to the bus bar case 20 according to the third example, the same parts as those of the bus bar case 20 according to the first example shown in Fig. 2 are denoted by the same reference numerals, and description thereof will be omitted.

[0061] In the first and second examples of the bus bar case 20, the cover body 41 is a single plate body, whereas in the third example of the bus bar case 20, the cover body 41 is divided into multiple parts. Specifically, the cover body 41 has multiple flat plate portions 44 and multiple elastic portions 45.

[0062] In this embodiment, there are four flat plate portions 44, one for each of the four protruding portions 42. The four flat plate portions 44, i.e., the first flat plate portion 44a, the second flat plate portion 44b, the third flat plate portion 44c, and the fourth flat plate portion 44d, are aligned in the planar direction. The first flat plate portion 44a supports the first protruding portion 42a. The second flat plate portion 44b supports the second protruding portion 42b. The third flat plate portion 44c supports the third protruding portion 42c. The fourth flat plate portion 44d supports the fourth protruding portion 42d. The first flat plate portion 44a and the second flat plate portion 44b are spaced apart from each other in the X direction. Similarly, the third flat plate portion 44c and the fourth flat plate portion 44d are spaced apart from each other in the X direction. The first flat plate portion 44a and the fourth flat plate portion 44d are at least partially spaced apart from each other in the Y direction. Similarly, the second flat plate portion 44b and the third flat plate portion 44c are spaced apart from each other in the Y direction.

[0063] In this embodiment, there are four elastic portions 45, corresponding to the arrangement of the four flat plate portions 44. The four elastic portions 45, i.e., the first elastic portion 45a, the second elastic portion 45b, the third elastic portion 45c, and the fourth elastic portion 45d, each connect adjacent flat plate portions 44. The first elastic portion 45a connects the first flat plate portion 44a and the fourth flat plate portion 44d in the Y direction. The second elastic portion 45b connects the first flat plate portion 44a and the second flat plate portion 44b in the X direction. The third elastic portion 45c connects the second flat plate portion 44b and the third flat plate portion 44c in the Y direction. The fourth elastic portion 45d connects the third flat plate portion 44c and the fourth flat plate portion 44d in the X direction. The four elastic portions 45 may have a semi-cylindrical shape that is convex along the protruding direction of each protruding portion 42, for example.

[0064] In this way, the busbar module 1 may have a plurality of protruding portions 42. The cover body 41 may have a plurality of flat plate portions 44 arranged in a planar direction and individually supporting each of the protruding portions 42, and a plurality of elastic portions 45 connecting two adjacent flat plate portions 44.

[0065] According to this busbar module 1, each protrusion 42 displaces appropriately in accordance with the surface shape of the busbar 10 with which it comes into contact, so that the cover body 41 follows the positional variations of the busbar 10, and the cover 40 can always be properly attached to the accommodating section 30.

[0066] In this embodiment, the second elastic portion 45b and the fourth elastic portion 45d are disposed so as to be furthest apart from each other in the Y direction. This provides the cover body 41 with a through-space equivalent to the through-hole 41e in the second example of the bus bar case 20, and therefore the third example of the bus bar case 20 can also achieve the same effect as the second example.

[0067] Fig. 5 is a perspective view showing a fourth example of the bus bar case 20. With regard to the bus bar case 20 according to the fourth example, the same parts as those of the bus bar case 20 according to the first example shown in Fig. 2 are denoted by the same reference numerals, and description thereof will be omitted.

[0068] In the first example of the busbar case 20, the protrusion 42 has an overall shape of a rectangular column and a tip portion 42e having a curved surface. However, the shape of the protrusion 42 is not limited to this. For example, the overall shape of the protrusion 42 may be cylindrical. Furthermore, the tip of the protrusion 42 may be a protrusion having any shape, such as a quadrangular pyramidal portion 42f shown in FIG. 5.

[0069] Furthermore, in the busbar module 1, the cover body 41 may have a locking portion 43 on an edge of the cover body 41. The accommodation section 30 may have a locked portion 33 on the outer surface 31e of the side wall portion 31, with which the locking portion 43 engages when the cover 40 is attached to the accommodation section 30.

[0070] In the above description with reference to the drawings, the edge on which the locking portion 43 is provided in the cover body 41 is the first edge 41c. On the other hand, the part of the side wall 31 on which the locked portion 33 is provided in the accommodation portion 30 is on the outer surface 31e side of the third side wall 31c.

[0071] According to this busbar module 1, the locking portion 43 and the locked portion 33, which function as a locking mechanism when the cover 40 is attached to the accommodating portion 30, are not located inside the accommodating portion 30, i.e., in the accommodating space S. Therefore, the accommodating space S can be kept large, which is one structure for reducing areas that may interfere when connecting a terminal such as the positive terminal 101 to the busbar 10 by bolting or the like.

[0072] Furthermore, in the busbar module 1, the busbar case 20 may have a deformable plate-shaped hinge portion 50. One end of the hinge portion 50 may be continuous with the outer surface 31e of the side wall portion 31, and the other end opposite to the one end of the hinge portion 50 may be continuous with an edge of the cover body 41.

[0073] In the above description with reference to the drawings, the outer surface 31e of the side wall 31 to which one end of the hinge 50 is continuous is the outer surface 31e of the first side wall 31a. On the other hand, the edge of the cover body 41 to which the other end of the hinge 50 is continuous is the second edge 41d.

[0074] According to this busbar module 1, the busbar case 20 has the housing portion 30 and the cover 40 integrated via the hinge portion 50. Therefore, the entire busbar case 20 can be manufactured by a simple process such as injection molding, and the number of parts constituting the busbar module 1 is reduced, which can be advantageous in terms of handling during work.

[0075] In addition, in the busbar case 20, it is not an essential requirement that the accommodating section 30 and the cover 40 be integrated via the hinge section 50, and the accommodating section 30 and the cover 40 may be separate entities without having the hinge section 50.

[0076] Although one embodiment has been described above, the embodiment is not limited to this, and various modifications are possible within the scope of the gist of the embodiment. [Explanation of symbols]

[0077] 1 Busbar Module 10 Busbar 20 Busbar case 21 First Opening 22 Second opening 30 Storage section 31 Side wall 31e Exterior 32 Support part 33 Locked part 40 Cover 41 Cover body 41c 1st edge 41d Second edge 41e Through hole 42 Protrusion 42a 1st protrusion 42b Second protrusion 42c 3rd protrusion 42d 4th protrusion 43 Locking part 44 Flat plate part 44a 1st flat plate part 44b 2nd flat plate part 44c 3rd flat plate part 44d 4th flat plate part 45 Elastic part 45a First elastic part 45b second elastic portion 45c Third elastic part 45d Fourth elastic part 50 Hinge part 100 D cells 100a 1st battery 100b Second battery 101 Positive terminal 102 Negative terminal

Claims

[Claim 1] A busbar module electrically connecting a first cell and a second cell, each of which has a pair of terminals, a positive terminal and a negative terminal, a bus bar connecting one terminal of the first cell and one terminal of the second cell, the terminals of which protrude in parallel with each other; an insulating bus bar case having a housing portion that houses the bus bar and a cover that is attached to the housing portion, the accommodation portion includes a frame-shaped side wall portion that surrounds the bus bar in a direction perpendicular to a connection direction of the terminals, and a support portion that supports the bus bar from a first opening side of the side wall portion that faces the first battery cell or the second battery cell, the cover includes a cover body that covers a second opening on the side wall portion opposite to the first opening, and a plurality of protrusions that protrude from the cover body toward the first opening and come into contact with the bus bar, the bus bar is held by simply being sandwiched between the support portion and the plurality of protrusions, the cover body has a plurality of flat plate portions arranged in a planar direction and individually supporting each of the protrusions, and a plurality of elastic portions connecting two adjacent flat plate portions.

Images