Multi-layer branched busbar and its manufacturing method

Abstract

The present invention relates to a multilayer branched busbar that is easy to manufacture and has various shapes, and a manufacturing method thereof.A branched busbar has at least two or more laminated conductive layers that are branched by partly separating at branch points.

Description

[Technical field]

[0001] This application claims the benefit of priority based on Korean Patent Application No. 2020-0168885 filed on December 4, 2020, and all contents disclosed in the documents of said Korean patent application are incorporated herein by reference.

[0002] The present invention relates to a multi-layer branched busbar and a manufacturing method thereof, and more particularly to a multi-layer branched busbar for connecting devices, batteries, etc. in parallel by branching busbars stacked in multiple layers, and a manufacturing method thereof. [Background technology]

[0003] In recent years, the demand for secondary batteries that can store generated electrical energy has been increasing due to the development of alternative energy sources to combat air pollution and energy depletion caused by the use of fossil fuels. Secondary batteries that can be charged and discharged are used in mobile devices, electric vehicles, hybrid electric vehicles, etc., and are becoming an integral part of everyday life.

[0004] Secondary batteries are used as energy sources for various electronic devices, which are essential in modern society, and are installed in various devices such as mobile devices and electric vehicles. Various types of battery cells are required according to the needs of users and the variety of shapes of the devices to which they are installed.

[0005] A secondary battery used in a small device is provided with several battery cells, whereas a battery module or battery pack in which a number of battery cells are electrically connected is used in an automobile or the like. In such a battery module or battery pack, a number of battery cells are connected in series and parallel to each other to improve capacity and output. In this case, the battery module or battery pack generally includes a number of stacked secondary batteries, i.e., battery cells, and includes a busbar module for electrically connecting the battery cells. The busbar module includes electrode leads connected to each battery cell, or a busbar for connecting the battery cells to each other.

[0006] Fig. 1 is a top view of a parallel connection busbar according to the related art. As shown in Fig. 1, a conventional parallel connection busbar 1 may include a trunk portion 10 connected to an energy supply portion that supplies energy to the parallel connection busbar 1, and branch portions 20 connected to the trunk portion 10 and connecting devices or batteries electrically connected to the parallel connection busbar 1 in parallel.

[0007] In the conventional parallel connection busbar 1, in order to form a multiple-branched configuration, the portions constituting each trunk 10 and the first branch portion 21, second branch portion 22, and third branch portion 23 constituting the branch portion 20 are formed separately and then connected.

[0008] However, the shape of each trunk portion 10 and branch portion 20 must be formed according to various forms of the parallel connection busbar 1 to be used, and a structure is required for connecting each trunk portion 10 and branch portion 20. Moreover, there is a risk that the connection of the connecting portion may become loose or defects may occur.

[0009] The following Patent Document 1 refers to a bus bar having a branched shape, but this has the disadvantage that each bus bar must be formed to match the desired bus bar shape.

[0010] Therefore, there is a need for a busbar configuration that is easy to modify into a desired shape and is easy to manufacture. [Prior art documents] [Patent documents]

[0011] [Patent Document 1] JP 2010-207059 A Summary of the Invention [Problem to be solved by the invention]

[0012] The present invention has been made to solve the above-mentioned problems, and has an object to provide a parallel connection bus bar that can be easily deformed into various shapes and causes less damage to connecting components. [Means for solving the problem]

[0013] In order to achieve the above-mentioned object, the busbar of the present invention is characterized in that at least two conductive layers are laminated, and the conductive layers are a branched busbar in which a part of the conductive layers is separated and branched at a branch point.

[0014] Also, the branch point may be a parallel connection section that connects members electrically connected by the branched conductive layers with the same voltage.

[0015] The number of conductive layers branched off in the parallel connection section may be determined based on the current specifications of each branched portion.

[0016] The number of branched conductive layers may be calculated using the following formula:

[0017] The formula is as follows: Number of conductive layers = Current specification of branched conductive layer / Sum of current specification of all conductive layers

[0018] Both ends of the branched conductive layer may have the same length.

[0019] Both ends of the branched conductive layer may be hole-machined after welding.

[0020] The conductive layer may be branched by bending a portion of the conductive layer.

[0021] The conductive layer may be made of a flexible material.

[0022] The conductive layer may be made of at least one of copper, a copper alloy, nickel, a nickel alloy, and aluminum.

[0023] The present invention may be a battery module including at least one of the branched busbars described above.

[0024] The present invention may be a battery pack including at least one of the branched bus bars described above.

[0025] The present invention may be a method for manufacturing a branched busbar, including the steps of (S1) stacking at least two or more conductive layers; (S2) welding one end of the conductive layers and drilling holes; (S3) bending some of the conductive layers to form one or more branch paths; and (S4) welding an end of each branch path and then drilling holes.

[0026] The method for manufacturing a branched busbar according to the present invention may further include (S4-0) cutting the other end of the branch path according to design conditions after repeating the step (S3) one or more times.

[0027] The present invention can also provide solutions to the above problems in various combinations as required. Effect of the Invention

[0028] As described above, the busbar according to the present invention can be easily deformed into various shapes, and the manufacturing process is simple because only one busbar having a multi-layer structure can be manufactured and then folded to form the busbar.

[0029] In addition, since the number of layers is determined according to the desired current specifications, the current specifications can be easily adjusted.

[0030] Furthermore, since one bus bar is bent to branch, the risk of connecting bus bars or the connection becoming loose is reduced. [Brief description of the drawings]

[0031] [Figure 1] FIG. 1 is a top view of a parallel connection bus bar according to the prior art. [Diagram 2]FIG. 2 is a top view of the branched bus bar according to the present invention. [Diagram 3] FIG. 2 is a side view of the branched bus bar according to the present invention. [Figure 4] FIG. 2 is a top view of the branched bus bar according to the present invention before branching. [Diagram 5] FIG. 2 is a top view of the branched busbar according to the present invention after the first branch. [Figure 6] FIG. 2 is a top view of the branched busbar according to the present invention after a second branch. [Figure 7] FIG. 13 is a top view of a branched bus bar according to still another embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0032] Hereinafter, with reference to the accompanying drawings, a detailed description will be given of an embodiment of the present invention that can be easily implemented by a person having ordinary skill in the art to which the present invention pertains. However, when describing the operation principle of the preferred embodiment of the present invention in detail, if it is determined that a detailed description of related publicly known functions or configurations may obscure the gist of the present invention, the detailed description will be omitted.

[0033] In addition, the same reference numerals are used throughout the drawings for parts having similar functions and actions. Throughout the specification, when a part is said to be connected to another part, this includes a direct connection as well as an indirect connection via another element between them. Furthermore, unless otherwise specified, the inclusion of a certain component does not mean the exclusion of other components, but means that other components may also be included.

[0034] Furthermore, unless otherwise specified, the description specifying the elements by limiting or adding components is applicable to any invention and is not limited to a specific invention.

[0035] Furthermore, throughout the description of the invention and the claims of this application, the singular "a" or "an" includes the plural, unless otherwise specified.

[0036] In addition, throughout the description of the invention and claims of this application, unless otherwise specified, "or" includes "and." Therefore, "including A or B" means any of the three cases including A, including B, or including both A and B.

[0037] FIG. 2 is a top view of the branched busbar according to the present invention, and FIG. 3 is a side view of the branched busbar according to the present invention.

[0038] The branched busbar 100 according to the present invention includes a trunk 110 connected to an energy supply unit that supplies main energy to the branched busbar 100, and branch portions 120 protruding from the trunk 110 and transmitting energy supplied from the energy supply unit in parallel.

[0039] As shown in FIG. 3, the branched busbar 100 according to the present invention has two or more laminated conductive layers.

[0040] The conductive layer may be made of a conductive material. For example, the conductive layer may be made of at least one of copper, a copper alloy, nickel, a nickel alloy, and aluminum. Specifically, the copper alloy may contain 60% or more by weight of copper based on the total weight, and more specifically, the copper alloy may contain 90% or more by weight of copper based on the total weight. The copper alloy may contain at least one selected from the group consisting of nickel, silicon, tin, iron, zinc, magnesium, phosphorus, chromium, and zirconium in the remaining weight % excluding the weight % of copper. For example, the copper alloy may contain 90% or more by weight of copper, less than 10% by weight of zinc, less than 10% by weight of chromium, and less than 5% by weight of zirconium. In another embodiment, the copper alloy may include 90% by weight or more of copper, less than 5% by weight of nickel, less than 1% by weight of silicon, less than 1% by weight of tin, less than 1% by weight of iron, less than 1% by weight of zinc, less than 0.1% by weight of magnesium, less than 0.1% by weight of phosphorus, and less than 0.1% by weight of zirconium. However, the branched busbar 100 is not limited to a copper alloy, and any metal alloy mainly made of nickel, aluminum, gold, silver, etc. may be used, and any material having good electrical conductivity may be used, such as conductive rubber, a gold-silver nanocomposite in which the surface of a silver nanowire is wrapped in gold and then mixed with SBS (poly Styrene-Butadiene-Styrene), carbon nanotubes, and carbon-rubber composites.

[0041] The conductive layer may be made of a flexible material. Since the conductive layer is made of a flexible material, the branched busbar 100 according to the present invention is not damaged even if some layers are broken. As an example, the conductive layer may be made of a metal having a thickness of 0.2 mm to 0.25 mm based on copper (C1100, 1 / 4H). If the conductive layer is too thin, it may be damaged when a part of the conductive layer is branched, and if the conductive layer is too thick, it is not possible to branch the conductive layer into a desired shape to form various busbar shapes.

[0042] The conductive layer has a tensile elongation of 10% or more and 25% or less, and a tensile strength of 215 N / mm 2More than 275N / mm 2 If the tensile elongation of the conductive layer is less than 10%, it may be difficult to branch the conductive layer, and if it exceeds 25%, the bus bar made of the conductive layer may not be fixed in a desired shape. 2 If the strength of the conductive layer is less than 275 N / mm 2 If the thickness exceeds 100 nm, it may be difficult to branch the conductive layer. As an example, the conductive layer may be made of a metal such as copper, a copper alloy, or aluminum.

[0043] The conductive layer is bent at a branch point A to form a branch portion 120 as shown in Fig. 2. The branch portion 120 may have a shape as shown in Fig. 2, in which the branch portion 120 is branched into two at the same branch point A, or may have a shape in which the branch portion 120 is branched at branch points A located at different positions.

[0044] The branch point A may be a parallel connection section that connects the members electrically connected by the branched conductive layer with the same voltage. The branch 120 branched by the branch point A may be formed to have a desired current specification so as to supply a specific power to a desired portion.

[0045] For this reason, each layer constituting each of the conductive layers is formed to the same thickness, and the number of conductive layers constituting the branched portion, i.e., the branch portion 120, can be determined based on the current specification.

[0046] As an example, the number of branched conductive layers may be calculated using the following formula:

[0047] Number of conductive layers = Current specification of branched conductive layer / Sum of current specifications of all conductive layers

[0048] As an example of application of the above formula, when the current specification of all conductive layers is 150 A, the first branch 121 has 100 A, the second branch 122 has 30 A, and the third branch 123 has 20 A, the above formula can be obtained and then converted into a constant for use. Ten conductive layers can be placed in the first branch 121, three conductive layers can be placed in the second branch 122, and two conductive layers can be placed in the third branch 123.

[0049] The branched busbar according to the present invention has an advantage that the current specifications can be accurately separated as described above because the branched busbar is formed by dividing a conductive layer made up of a plurality of layers.

[0050] Alternatively, the thickness of the branched conductive layer may be made different, and the thickness of each branch portion 120 may be determined in accordance with the current specification of the branched conductive layer.

[0051] Each branch 120 of the conductive layer may be formed by bending a portion of the conductive layer at the trunk 110 .

[0052] 4 to 6 show the process of folding a part of the conductive layer.

[0053] FIG. 4 is a top view of a branched busbar according to the present invention before branching, FIG. 5 is a top view of the branched busbar according to the present invention after a first branching, and FIG. 6 is a top view of the branched busbar according to the present invention after a second branching.

[0054] As shown in FIG. 4, branched busbar 100 according to the present invention before branching initially has a form in which conductive layers are laminated so that only trunk portion 110 exists.

[0055] All of the conductive layers may have the same length, but the lengths of each of the conductive layers may be set to be different, taking into account the fact that some of the conductive layers constituting the branched busbar 100 may be folded.

[0056] (S1) After laminating at least two conductive layers, branched busbar 100 according to the present invention has (S2) one end of the laminated conductive layers welded to form trunk connection hole 131.

[0057] The conductive layers of the branched busbar 100 may be mechanically fixed to one another or may be integrally formed, such as by ultrasonic welding or laser welding.

[0058] As described above, when one end of the stem 110 is welded, the laminated conductive layers can be fixed so that the conductive layers do not move when branching. In addition, when a stem connection hole 131 is formed at one end of the stem 110, the stem connection hole 131 can be used to fix the branched busbar 100 when branching, or to fix the branched busbar 100 to a battery module, a battery pack, or other components.

[0059] The branched busbar 100 has branch portions 120 formed by bending or dividing a part of a trunk portion 110, in which the conductive layers are laminated in a plurality of layers, into a plurality of layers.

[0060] The branch portion 120 may be formed at the same branch point A as shown in FIG. 2, or as shown in FIG. 5, the second branch portion 122 may be formed without another branch, and the first branch portion 121 and the third branch portion 123 may be branched at different branch points A to form the branch portion 120.

[0061] 6, the branched busbar 100 may further branch an already branched branch 120, i.e., a first branch 121, to form a branched branch 121(a). In this case, the first branch 121 needs to be formed in at least two layers in order to form the branched branch 121(a).

[0062] As described above, in the branched busbar 100 according to the present invention, (S3) some of the conductive layers are folded to form one or more branch paths, and (S4) holes can be machined after welding the ends of each branch path. At this time, the holes are branch connection holes 132, which can be used to connect the busbar to a battery module, a battery pack, or other components.

[0063] By the above-described welding, one branched busbar 100 can be formed, and each conductive layer of the branch portions 120 of the branched branched busbar 100 can be fixed.

[0064] At this time, both ends of the branched busbar 100 may have the same length. This is to allow devices, battery modules, or battery packs using the branched busbar 100 to be positioned at a fixed position. In order to form the branched busbar 100 to a fixed length, each conductive layer of the branched busbar 100 may be laminated to a different length, or a process of (S3) bending some of the conductive layers of the branched busbar 100 to form one or more branch paths may be performed one or more times, and then (S4-0) cutting the other end of the branch path according to design conditions may be performed. When the other end of the branch path is cut as described above, there is an advantage that all the conductive layers of the branched busbars 100 can be formed to the same length, making it easy to branch.

[0065] FIG. 7 is a top view of a branched bus bar according to still another embodiment of the present invention.

[0066] As shown in FIG. 7, a branched busbar 200 according to yet another embodiment of the present invention may have the conductive layers stacked side-by-side, unlike the conductive layers shown in FIGS.

[0067] In this case, the width of the metal part of the trunk part 210 in the direction of lamination of the conductive metal has a certain width, but the thickness part not in the direction of lamination may be thin, thereby making it possible to obtain a bus bar having a certain thickness and width.

[0068] When forming the branches 220 of the branched busbar 200, the conductive layers stacked side by side on the trunk 210 may be bent into a certain shape.

[0069] As described above, when the conductive layers of the branched busbar 200 are stacked side by side, it is easy to form the branch portions 220 of the branched busbar 200, and the risk of the conductive layers breaking due to the formation of the branch portions 220, resulting in an increase in resistance, can be reduced.

[0070] In accordance with still another embodiment of the present invention, the branched busbar 200 may be subjected to a process of welding the entire branched busbar 200 after branching in order to reduce the risk of the branched busbars 200 being separated from each other by stacking them side by side.

[0071] The branched busbar according to the present invention may be included in a battery module or a battery pack, and may be used in various devices to connect the devices in parallel.

[0072] Those skilled in the art will appreciate that various applications and modifications within the scope of the present invention will be possible based on the above content. [Explanation of symbols]

[0073] 1 Parallel connection busbar 100,200 Branch busbar 10,110,210 executives 20,120,220 Branch 21,121,221 First Branch 121(a) Branch 22,122,222 Second Branch 23,123,223 Third Branch 130 Connecting Halls 131 Executive Hall 132 Branch Connection Hall A Branch Point A' 2nd branch point

Claims

1. At least two conductive layers are laminated, and the conductive layers are branched at branch points, at which a part of the conductive layers is branched. a portion of the conductive layer is bent so that one main surface of the portion of the conductive layer faces and contacts with the other main surface of the portion of the conductive layer, forming an angle of 90°, and a tip of the portion of the conductive layer is bent away from an end of the portion of the conductive layer.

2. The branched busbar according to claim 1 , wherein the branch point is a parallel connection section that connects members electrically connected by the branched conductive layers at the same voltage.

3. The branched busbar according to claim 2 , wherein a number of conductive layers branched off in the parallel connection section is determined based on a current specification of each branched portion.

4. The branched busbar according to claim 3 , wherein the number of the branched conductive layers is calculated by the following formula: Number of conductive layers = Current specification of branched conductive layer / Sum of current specifications of all conductive layers

5. The branched busbar according to any one of claims 1 to 4, wherein both ends of the branched conductive layers have the same length.

6. The branched bus bar according to any one of claims 1 to 5, wherein both ends of the branched conductive layer are subjected to hole processing after welding.

7. The branched busbar according to any one of claims 1 to 6, wherein the conductive layer is made of a thin and flexible material.

8. The branched busbar of claim 7 , wherein the conductive layer is made of copper.

9. A battery module comprising a branched busbar according to any one of claims 1 to 8.

10. A battery pack comprising a branched busbar according to any one of claims 1 to 8.

11. (S1) a step of laminating at least two conductive layers; (S2) welding one end of the conductive layer and drilling a hole; (S3) folding a portion of the conductive layer to form one or more branch paths; and (S4) The step of welding the ends of each branch path and then drilling holes A method for manufacturing a branched bus bar comprising the steps of:

12. (S4-0) The method of manufacturing a branched busbar according to claim 11, further comprising the step of cutting the other end of the branch path according to a design condition after repeating the step (S3) one or more times.

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