Laminated Bass Bar
The laminated busbar design with slits in intermediate portions addresses tolerance issues by enabling deformation and alignment adjustments, improving connectivity and stability in battery cell connections.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- YAZAKI CORP
- Filing Date
- 2024-12-05
- Publication Date
- 2026-06-17
AI Technical Summary
Conventional laminated bus bars struggle to appropriately absorb tolerances with connection targets, particularly in the connection of battery cells, leading to potential misalignment and inefficiencies.
The laminated busbar design incorporates flat busbars with connecting portions and intermediate portions, featuring slits that penetrate along the lamination direction, allowing for tolerance absorption while minimizing enlargement.
The design effectively absorbs tolerances in the connection process, ensuring proper alignment and stability by allowing deformation along the extension and width directions, enhancing connectivity and reducing size enlargement.
Smart Images
Figure 2026098242000001_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a laminated bus bar.
Background Art
[0002] As a technology related to a conventional laminated bus bar, for example, Patent Document 1 discloses a power storage module including a plate-shaped bus bar that connects a plurality of power storage elements. The bus bar has a plurality of connection portions connected to the electrode terminals of the plurality of power storage elements, and one or more intermediate portions that connect adjacent connection portions. The intermediate portion is a mountain-shaped portion that protrudes in a direction away from the electrode terminal from the connection portion, and one or more slits are provided.
Prior Art Documents
Patent Documents
[0003]
Patent Document 1
Summary of the Invention
Problems to be Solved by the Invention
[0004] By the way, in the above conventional laminated bus bar, for example, slits are provided in the mountain-shaped portions of the plurality of bus bars, but there is room for further improvement in appropriately absorbing the tolerance with the connection target.
[0005] The present invention has been made in view of the above circumstances, and an object thereof is to provide a laminated bus bar that can appropriately absorb the tolerance with the connection target.
Means for Solving the Problems
[0006] To achieve the above objective, the laminated busbar according to the present invention comprises a plurality of flat busbars laminated along the lamination direction, each of the plurality of flat busbars having a pair of connecting portions connected to the object to be connected, and an intermediate portion provided between the pair of connecting portions and formed flat along an extending direction intersecting the lamination direction together with the connecting portions, and each of the plurality of flat busbars is provided with a slit that penetrates along the lamination direction in the intermediate portion. [Effects of the Invention]
[0007] In the laminated busbar according to the present invention, each of the multiple flat busbars has an intermediate portion that is formed flat along the extension direction together with a pair of connecting portions, and is provided with a slit that penetrates along the lamination direction. With this configuration, the laminated busbar can absorb tolerances with respect to the object it is connected to, for example, by the slit provided in the intermediate portion, while suppressing its enlargement along the lamination direction. As a result, the laminated busbar has the effect of being able to properly absorb tolerances with respect to the object it is connected to. [Brief explanation of the drawing]
[0008] [Figure 1] Figure 1 is an illustrative plan view of a laminated busbar according to an embodiment. [Figure 2] Figure 2 is an exemplary cross-sectional view of a laminated busbar according to the embodiment. [Figure 3] Figure 3 is an illustrative plan view of a plurality of flat busbars of a laminated busbar according to an embodiment. [Figure 4] Figure 4 is an illustrative plan view of a modified laminated busbar. [Figure 5] Figure 5 is an illustrative cross-sectional view of a modified laminated busbar. [Figure 6] Figure 6 is a plan view illustrating multiple flat busbars of a modified laminated busbar. [Modes for carrying out the invention]
[0009] Embodiments and modifications of the present invention will be described in detail below with reference to the drawings. However, the present invention is not limited by the embodiments and modifications described below. Furthermore, the components in the embodiments and modifications described below include those that are easily substituted or substantially identical to those that are easily substituted by those skilled in the art.
[0010] Furthermore, the embodiments and modifications disclosed below include similar components. Therefore, in the following, these similar components are given common reference numerals, and redundant descriptions are omitted. In this specification, ordinal numbers are used solely to distinguish parts, components, parts, positions, directions, etc., and do not indicate order or priority.
[0011] [Embodiment] Figure 1 is a plan view of a stacked busbar 1 according to an embodiment. The stacked busbar 1 of this embodiment shown in Figure 1 electrically connects multiple battery cells of a battery pack mounted on a vehicle such as an electric vehicle or a hybrid vehicle. The stacked busbar 1 of this embodiment is composed of a plurality of flat busbars 10, and a pair of electrode terminals of two adjacent battery cells are electrically connected to a pair of connection parts 11 provided at both ends of the plurality of flat busbars 10. In this embodiment, the electrode terminals of the battery cells are an example of what to connect. The stacked busbar 1 is not limited to this example and may be applied to circuits in an electrical junction box, to connections between an inverter and a motor, or to high-voltage power transmission lines extending in the longitudinal direction of a vehicle.
[0012] In the following explanation, of the three intersecting directions, the first direction will be referred to as the "extension direction X," the second direction as the "width direction Y," and the third direction as the "stack direction Z." Here, the extension direction X, the width direction Y, and the stacking direction Z are approximately orthogonal to each other. The extension direction X typically corresponds to the extension direction (longitudinal direction) of the stacked busbar 1. The width direction Y typically corresponds to the width direction (short direction) of the stacked busbar 1. The stacking direction Z typically corresponds to the height direction (vertical direction) of the stacked busbar 1, the stacking direction of the multiple flat busbars 10 of the stacked busbar 1, etc.
[0013] Figure 2 is a cross-sectional view of the laminated busbar 1, and Figure 3 is a plan view of the multiple flat busbars 10 of the laminated busbar 1. As shown in Figures 2 and 3, the laminated busbar 1 comprises, for example, multiple flat busbars 10 stacked along the stacking direction Z. The flat busbars 10 are terminal fittings made of a conductive metal material and are electrically connected to the electrode terminals of the battery cell, which is the object to be connected as described above. In this embodiment, the laminated busbar 1 is provided with five flat busbars 10 arranged along the stacking direction Z. Note that the laminated busbar 1 is not limited to this example and may be composed of, for example, two, three, four, or six or more flat busbars 10.
[0014] The flat busbar 10 is formed from, for example, copper, copper alloy, aluminum, aluminum alloy, etc. The flat busbar 10 is a flat conductor formed in a substantially rectangular plate shape. The flat busbar 10 extends along the extending direction X, and the cross-sectional shape perpendicular to the extending direction X is formed in a substantially rectangular shape. The flat busbar 10 is formed to extend along the extending direction X with substantially the same cross-sectional shape. The thickness of the flat busbar 10 along the stacking direction Z is formed to be significantly thinner than the length along the extending direction X and the width along the width direction Y. Here, the flat busbar 10 is typically formed in the form of a flexible thin film plate (foil-like, strip-like).
[0015] The flat busbars 10 are stacked and laminated together along the lamination direction Z to form a laminated busbar 1. The multiple flat busbars 10 that make up the laminated busbar 1 are typically made of the same material and have the same cross-sectional shape perpendicular to the extension direction X, i.e., the same thickness and width. The multiple flat busbars 10 that are stacked together to form the laminated busbar 1 have the extension direction X, the lamination direction Z, and the width direction Y coincide with each other.
[0016] In the laminated busbar 1, at least a portion of the flat busbars 10 are in contact with and electrically connected to other flat busbars 10 adjacent to each other in the stacking direction Z. In this embodiment, all the flat busbars 10 constituting the laminated busbar 1 are in contact with and electrically connected to adjacent flat busbars 10 when stacked. That is, in this embodiment, the laminated busbar 1 is formed such that all the flat busbars 10 constituting the laminated busbar 1 are at the same potential.
[0017] Each of the multiple flat busbars 10 is composed of, for example, a pair of connecting portions 11 provided at both ends in the extending direction X, and an intermediate portion 12 provided between the pair of connecting portions 11. The pair of connecting portions 11 are the parts that are electrically and mechanically connected to the electrode terminals of the battery cell, which is the object to be connected as described above. The pair of connecting portions 11 are provided with mounting holes 11a into which the electrode terminals are inserted along the stacking direction Z. The mounting holes 11a are through holes that penetrate the pair of connecting portions 11 along the stacking direction Z, and are configured, for example, as round holes along the outer circumferential surface of the electrode terminals. The pair of connecting portions 11 are electrically and mechanically connected to the electrode terminals by joining them together, for example, by welding, with the electrode terminals inserted into each of the mounting holes 11a.
[0018] The middle portion 12 is provided between the pair of connection portions 11 and is a portion that connects the pair of connection portions 11. In the present embodiment, the middle portion 12 is formed flat along the extending direction X together with the pair of connection portions 11. That is, the flat bus bar 10 is connected to the pair of connection portions 11 and the middle portion 12 without a step or the like along the stacking direction Z between the pair of connection portions 11 and the middle portion 12. The middle portion 12 and the pair of connection portions 11 extend along the extending direction X and are formed so as to extend with substantially the same cross-sectional shape along the extending direction X. The middle portion 12 and the pair of connection portions 11 constitute both end portions 10c (long side portions) in the width direction Y of the flat bus bar 10, and the pair of connection portions 11 constitute both end portions 10d (short side portions) in the extending direction X of the flat bus bar 10.
[0019] Here, in the present embodiment, a slit 13 is provided in each middle portion 12 of the plurality of flat bus bars 10. The slit 13 is, for example, a through hole penetrating the middle portion 12 along the stacking direction Z and extends along a direction intersecting the stacking direction Z. In the present embodiment, a plurality of slits 13 are provided in each middle portion 12 of the flat bus bar 10 at intervals along the extending direction X. In the present embodiment, six slits 13 are provided side by side along the extending direction X in the flat bus bar 10, but the number of slits 13 is not limited to this example and can be variously changed.
[0020] Further, the plurality of slits 13 extend along an inclined direction that is inclined with respect to the extending direction X, for example. The extending direction X is typically the longitudinal direction of the flat bus bar 10, the direction in which the plurality of slits 13 are arranged, and the direction connecting the pair of connection portions 11. Also, in the present embodiment, when viewed from the stacking direction Z (see FIG. 3), the plurality of slits 13 extend along an inclined direction between the extending direction X and the width direction Y. Specifically, in the present embodiment, for example, the inclination angle (the smaller angle) of the plurality of slits 13 with respect to the extending direction X (both end portions 10c) is about 45°, and the inclination angle (the smaller angle) of the plurality of slits 13 with respect to the width direction Y (both end portions 10d) is about 45°. Thus, in the present embodiment, the plurality of slits 13 extend parallel to each other in the intermediate portion 12. Also, both ends of the plurality of slits 13 are arranged along the extending direction X and are formed to have substantially the same length as each other.
[0021] Also, the plurality of flat bus bars 10 are stacked in a state where the entire slits 13 of two adjacent flat bus bars 10 adjacent to each other along the stacking direction Z overlap each other. That is, in the present embodiment, the plurality of flat bus bars 10 have all regions of the respective slits 13 overlapping each other along the stacking direction Z. In the present embodiment, when viewed from the stacking direction Z, the plurality of flat bus bars 10 are stacked along the stacking direction Z in the same posture in which the plurality of slits 13 extend parallel to each other. The posture of the plurality of flat bus bars 10 is, for example, a posture in which each front surface 10a is positioned on one end side in the stacking direction Z, each back surface 10b is positioned on the other end side in the stacking direction Z, and one of each connection portion 11 is positioned on one end side in the extending direction X and the other of each connection portion 11 is positioned on the other end side in the extending direction X.
[0022] As described above, in the laminated busbar 1 of this embodiment, each of the multiple flat busbars 10 has an intermediate portion 12 formed flat along the extending direction X together with a pair of connecting portions 11, and is provided with a slit 13 that penetrates along the stacking direction Z. With this configuration, the laminated busbar 1 can absorb tolerances with respect to the object to be connected by the slit 13 provided in the intermediate portion 12, while suppressing an increase in size along the stacking direction Z. As a result, the laminated busbar 1 can properly absorb tolerances with respect to the object to be connected. Furthermore, the laminated busbar 1 can absorb tolerances (differences in height) of a pair of electrode terminals of a battery cell, which is the object to be connected and joined to the mounting holes 11a of the pair of connecting portions 11, by the multiple flat busbars 10 stacked along the stacking direction Z.
[0023] Furthermore, in the laminated busbar 1 of this embodiment, the slit 13 extends along an inclined direction that is inclined with respect to the extension direction X. With this configuration, for example, the laminated busbar 1 allows multiple flat busbars 10 to deform (expand or contract) along the extension direction X and width direction Y by the slit 13, and thereby can absorb tolerances along the extension direction X and width direction Y between the connected object and the busbar 1.
[0024] Furthermore, in the laminated busbar 1 of this embodiment, the multiple flat busbars 10 are laminated in such a state that the entire slits 13 of two adjacent flat busbars 10 overlap each other along the lamination direction Z. With this configuration, the laminated busbar 1 can, for example, be easily deformed (expanded or contracted) equally along the extension direction X and the width direction Y, and thereby properly absorb tolerances along the extension direction X and the width direction Y between it and the object to be connected.
[0025] Furthermore, in the laminated busbar 1 of this embodiment, multiple flat busbars 10 are provided with multiple slits 13 spaced apart from each other along the extending direction X in their respective intermediate portions 12. With this configuration, for example, the multiple flat busbars 10 can be more easily deformed (expanded or contracted) along the extending direction X and the width direction Y by the multiple slits 13, and consequently, tolerances along the extending direction X and the width direction Y between the laminated busbar 1 and the object to be connected can be absorbed more appropriately.
[0026] [Differentiation] Figure 4 is a plan view of a modified laminated busbar 1A, Figure 5 is a cross-sectional view of the laminated busbar 1A, and Figure 6 is a plan view of the multiple flat busbars 10 of the laminated busbar 1A. The laminated busbar 1A shown in Figures 4 to 6 has the same configuration as the laminated busbar 1 of the above embodiment. Therefore, the laminated busbar 1A can obtain the same operation and effect as the above embodiment based on the same configuration.
[0027] However, in this modified example, as shown in Figures 4 to 6, the multiple flat busbars 10 are stacked in a state where the slits 13 of two adjacent flat busbars 10 intersect and partially overlap each other along the stacking direction Z, which is different from the above embodiment. In other words, in this modified example, the flat busbar 10 is composed of a plurality of first flat busbars 10A and a plurality of second flat busbars 10B stacked along the stacking direction Z in a different orientation from the plurality of first flat busbars 10A.
[0028] The first flat busbar 10A is stacked along the stacking direction Z in a first orientation among a plurality of flat busbars 10. The first orientation is, for example, the orientation in which the flat busbar 10 of the above embodiment is inverted, in other words, the orientation in which the second flat busbar 10B (see Figure 6) is inverted. Specifically, the first orientation is, for example, the orientation in which each back surface 10b is located on one end side of the stacking direction Z, each front surface 10a is located on the other end side of the stacking direction Z, and one of the connecting parts 11 is located on one end side of the extending direction X, while the other of the connecting parts 11 is located on the other end side of the extending direction X.
[0029] The first orientation is not limited to this example, and may be, for example, an orientation in which each surface 10a is located on one end side of the stacking direction Z, each back surface 10b is located on the other end side of the stacking direction Z, and one of the connecting parts 11 is located on the other end side of the extending direction X, while the other of the connecting parts 11 is located on one end side of the extending direction X. The first flat busbar 10A is provided, for example, at both ends of the stacking direction Z and in the center of the stacking direction Z of the stacked busbar 1A.
[0030] The second flat busbar 10B is stacked along the stacking direction Z in a second orientation among the multiple flat busbars 10. The second orientation is, for example, the same orientation as the flat busbar 10 in the above embodiment, in other words, the orientation of the first flat busbar 10A inverted. Specifically, the second orientation is, for example, an orientation in which each surface 10a is located on one end side of the stacking direction Z, each back surface 10b is located on the other end side of the stacking direction Z, and one of the connecting parts 11 is located on one end side of the extending direction X, while the other of the connecting parts 11 is located on the other end side of the extending direction X.
[0031] The second flat busbar 10B is provided in the laminated busbar 1A between two first flat busbars 10A that are aligned along the lamination direction Z. Therefore, in this modified example, the laminated busbar 1A is arranged such that the slits 13 of two adjacent first flat busbars 10A and second flat busbars 10B intersect and partially overlap each other along the lamination direction Z. When viewed from the lamination direction Z, the first flat busbar 10A extends along a first imaginary line connecting a pair of corners located on opposite diagonals, with multiple slits 13. Similarly, when viewed from the lamination direction Z, the second flat busbar 10B extends along a second imaginary line connecting a pair of corners located on another opposite diagonal, with multiple slits 13.
[0032] As described above, in the laminated busbar 1A of this modified example, the multiple flat busbars 10 are laminated in a state where the slits 13 of two adjacent flat busbars 10 intersect and partially overlap along the lamination direction Z. With this configuration, the laminated busbar 1A can, for example, be easily deformed (expanded or contracted) uniformly along the extension direction X and width direction Y of the multiple flat busbars 10, and thereby can properly absorb tolerances along the extension direction X and width direction Y between it and the object to be connected.
[0033] In this modified example and the above embodiment, the multiple slits 13 provided on one of the multiple flat busbars 10 are shown to be arranged parallel to each other along an inclination direction that is inclined with respect to the extending direction X. However, the example is not limited to this, and for example, they may be arranged to intersect each other. Also, in this modified example and the above embodiment, the pair of connection parts 11 of the flat busbar 10 are shown to be provided with mounting holes 11a into which the electrode terminals of the battery cell to be connected are inserted. However, the example is not limited to this, and for example, the pair of connection parts 11 may not have mounting holes 11a, and the electrode terminals may be joined to the surface 10a or back surface 10b of the pair of connection parts 11 by laser welding or the like.
[0034] Although embodiments and modifications of the present invention have been illustrated above, these embodiments and modifications are merely examples and are not intended to limit the scope of the invention. The above embodiments and modifications can be implemented in various other forms, and various omissions, substitutions, combinations, and changes can be made without departing from the spirit of the invention. Furthermore, each configuration, shape, and other specifications (structure, type, direction, form, size, length, width, thickness, height, number, arrangement, position, material, etc.) can be modified as appropriate. [Explanation of Symbols]
[0035] 1, 1A laminated busbar 10 Flat Bass Bar 10a surface 10b back side 11 Connection part 12. Middle section 13 slits X extension direction Y width direction Z stacking direction
Claims
1. It comprises multiple flat busbars stacked along the stacking direction, Each of the multiple flat busbars has a pair of connecting portions that are connected to the object to be connected, and an intermediate portion provided between the pair of connecting portions and formed flat along an extending direction that intersects the stacking direction together with the connecting portions. Each of the multiple flat busbars is provided with a slit that penetrates through the intermediate portion along the stacking direction. Laminated bass bar.
2. The slit extends along an inclined direction that is inclined with respect to the extending direction. The laminated busbar according to claim 1.
3. Multiple flat busbars are stacked such that the entire slits of two adjacent flat busbars overlap each other along the stacking direction. The laminated busbar according to claim 2.
4. Multiple flat busbars are stacked in such a state that the slits of two adjacent flat busbars intersect and partially overlap each other along the stacking direction. The laminated busbar according to claim 2.
5. Multiple flat busbars are provided with multiple slits in their intermediate portions, spaced apart from each other along the extending direction. A laminated busbar according to claim 1 or 2.