Bus bar and battery pack comprising same

Abstract

The present invention relates to a bus bar comprising: a bus bar body having a structure in which a plurality of conductive layers are stacked; coupling portions at both ends of the bus bar main body to fix the plurality of conductive layers; and an insulating layer provided on at least a portion of an outer surface of the bus bar body, in which connection between the plurality of conductive layers is established only at the coupling portion.

Description

Technical Field

[0001] This application claims priority to Korean Patent Application No. 2024-0094540, filed on July 17, 2024, the disclosure of which is incorporated herein by reference in its entirety.

[0002] This invention relates to busbars and battery packs including such busbars. More specifically, this invention relates to busbars and battery packs including such busbars, which enable the electrical interconnection of multiple electrical components formed in various sizes, while preventing wasted space when the electrical components are stacked in the battery pack to have various shapes in the height or width direction. Background Technology

[0003] With stricter carbon emission regulations, the demand for environmentally friendly energy is increasing, and the number of devices using lithium-ion batteries as an energy source is also growing.

[0004] Even in fields such as electric vehicles that require high-output and high-capacity energy, lithium-ion batteries are increasingly being assembled into battery modules and battery packs.

[0005] Typically, a battery pack is manufactured by accommodating and assembling a battery cell stack comprising multiple battery cells arranged in close contact with each other in series and / or in parallel within a battery pack housing, and the battery pack can be designed taking into account the required capacity and output of the device to which the battery pack is applied.

[0006] If only fixed-size battery modules or battery modules are used in the manufacture of high-capacity battery packs, it may be difficult to manufacture the desired high-capacity battery packs.

[0007] Figure 1 These are 3D and cross-sectional views of a standard busbar.

[0008] Reference Figure 1 (a) is an overall perspective view of the busbar, and (b) is a cross-sectional perspective view of the busbar taken along line A'-A" of (a). The busbar 100 includes: a busbar body 110 made of conductive material; connecting portions 130 located at both ends of the busbar body 110; and an insulating layer 120 attached to the remaining portion of the busbar body 110 except for the connecting portions 130. Referring to (b), since the busbar body 110 is configured as a single metal strip, deformation of the busbar 100 (such as bending or twisting) is difficult.

[0009] When battery modules are connected to each other using busbars of uniform thickness and fixed shape, if the battery modules or electrical components are not stacked in a standardized manner within the battery pack, a large number of busbars may be required to connect the battery modules, making it difficult to efficiently utilize the internal space of the battery pack. Therefore, the internal space of the battery pack may be unnecessarily wasted and not used to increase capacity.

[0010] If wasted space can be reduced and the space occupied by battery modules in the battery pack can be increased, larger capacity battery packs can be manufactured, and therefore busbars that can be freely bent or deformed in various ways are needed.

[0011] Patent Document 1 relates to a flexible busbar and a method for manufacturing the same, wherein the flexible busbar includes: a conductor portion configured such that a plurality of metal plates are stacked; a first terminal portion and a second terminal portion located at both ends in the length direction of the conductor portion; and an insulating resin coating layer applied to the outer peripheral surface of the conductor portion.

[0012] The method for manufacturing a flexible busbar disclosed in Patent Document 1 includes the following steps: stacking a plurality of metal plates; applying insulating resin to the surface of the metal plates except for their two edges; fixing one edge of each of the metal plates; processing the metal plates into a predetermined shape; and fixing the other edge of each of the metal plates.

[0013] Patent Document 2 relates to a flexible busbar, wherein the flexible busbar includes: a conductor portion configured such that a plurality of plate-shaped conductors are stacked; a terminal portion formed at both ends in the length direction of the conductor portion; and a tube member configured to wrap around a predetermined portion of the conductor portion.

[0014] The method for manufacturing a flexible busbar disclosed in Patent Document 2 includes the following steps: stacking plate-shaped conductors; welding a first terminal portion to one end of each of the plate-shaped conductors in the length direction; covering the plate-shaped conductors; bending the covered conductor portion into a specific shape; and welding a second terminal portion to the other end of each of the plate-shaped conductors in the length direction.

[0015] As described above, in the flexible busbars of Patent Documents 1 and 2, the finished product is manufactured by deforming the conductor portion into a specific shape during the manufacturing process, thus making it possible to manufacture a flexible busbar with a specific shape; however, it is difficult to deform the flexible busbar so that it can be used in various environments where the flexible busbar is applied.

[0016] Therefore, there is a high demand for busbars that can be easily deformed as needed to connect to the terminals of battery modules arranged in various ways in the battery pack.

[0017] (Existing technical documents)

[0018] (Patent Document 1) Korean Patent Application Publication No. 2021-0053531 (May 12, 2021)

[0019] (Patent Document 2) Korean Patent Application Publication No. 2020-0116880 (October 13, 2020) Summary of the Invention

[0020] Technical issues

[0021] The present invention was made in view of the above-mentioned problems, and the object of the present invention is to provide a busbar and a battery pack including the busbar, the busbar being easily bent and thus freely deformable in a manner appropriate to the usage environment.

[0022] Technical solution

[0023] The busbar according to the present invention, which achieves the above objectives, comprises: a busbar body configured to have a plurality of conductive layers stacked thereon; a fusion portion connected to both ends of the busbar body to fix the plurality of conductive layers; and an insulating layer attached to at least a portion of the outer surface of the busbar body, wherein the plurality of conductive layers are connected to each other only at the fusion portion.

[0024] The connecting parts can be located at both ends of the busbar body, and fastening through holes can be formed in the connecting parts. An insulating layer can be attached to cover the remaining outer surface of the busbar body, excluding the connecting parts.

[0025] At least one through-hole or slit may be formed in at least one of the multiple conductive layers.

[0026] Through-holes or slits can be formed in all the multiple conductive layers, and all conductive layers can be formed in the same shape.

[0027] Vias or slits can be formed in all of the multiple conductive layers, and the area of ​​the vias or slits can gradually increase from the innermost conductive layer to the outermost conductive layer.

[0028] Each of the multiple conductive layers can be configured as a grid pattern in which the first and second lines intersect.

[0029] Multiple conductive layers can be configured such that the thickness and spacing of the first and second lines are constant.

[0030] In multiple conductive layers, the thickness of the first line and the second line can gradually decrease from the innermost conductive layer to the outermost conductive layer, and the spacing between the first line and the second line can gradually increase from the innermost conductive layer to the outermost conductive layer.

[0031] In multiple conductive layers, the thickness of the conductive layer can gradually decrease from the innermost conductive layer to the outermost conductive layer.

[0032] The fusion section can be formed by welding to attach and fix the ends of multiple conductive layers.

[0033] A non-flexible busbar with an insulating layer attached to the outer surface of a metal strip can be connected to at least one of a first end and a second end of the busbar body.

[0034] Additionally, the present invention provides a battery pack including electrical components electrically connected to each other via busbars. The battery pack may include busbars and electrical components to which the busbars are connected, wherein the busbars may be connected to the electrical components in a state where the busbars are bent to form at least one bend.

[0035] Furthermore, the present invention can provide various combinations of the above solutions.

[0036] Beneficial effects

[0037] The busbar according to the present invention can be freely deformed in a manner corresponding to the usage environment.

[0038] Therefore, the space required for interconnecting electrical components in the battery pack can be minimized, thereby reducing unnecessary space waste in the battery pack. Attached Figure Description

[0039] Figure 1 These are 3D and cross-sectional views of a standard busbar.

[0040] Figure 2 These are perspective views and partially enlarged cross-sectional views of the busbar according to the present invention.

[0041] Figure 3 This is an exploded perspective view of the main body of the busbar according to the first embodiment.

[0042] Figure 4 This is an exploded perspective view of the main body of the busbar according to the second embodiment.

[0043] Figure 5 This is an exploded perspective view of the main body of the busbar according to the third embodiment.

[0044] Figure 6 This is an exploded perspective view of the main body of the busbar according to the fourth embodiment.

[0045] Figure 7 These are perspective and cross-sectional views of the busbar according to the fifth embodiment.

[0046] Figure 8 yes Figure 7A magnified view of a portion of the image. Detailed Implementation

[0047] Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, enabling those skilled in the art to readily implement these preferred embodiments. However, in describing the operational principles of the preferred embodiments of the present invention, detailed descriptions of known functions and configurations incorporated herein will be omitted where such descriptions might obscure the subject matter of the invention.

[0048] Throughout the accompanying drawings, the same reference numerals will be used to refer to parts that perform similar functions or operations. Where, throughout the specification, one part is referred to as being connected to another part, that one part can be directly connected to the other part, and also indirectly connected to the other part via yet another part. Furthermore, unless otherwise stated, including an element does not mean excluding other elements, but rather means that these elements may be further included.

[0049] Unless otherwise specified, descriptions of elements by limitation or appendage can be applied to all inventions and do not limit any particular invention.

[0050] In the description of the invention and the claims of this application, unless otherwise stated, the singular form is intended to include the plural form.

[0051] In the description of this invention and the claims of this application, unless otherwise stated, "or" includes "and". Therefore, "including A or B" means three cases: including A, including B, and including both A and B.

[0052] Embodiments of the present invention will be described in more detail with reference to the accompanying drawings.

[0053] Figure 2 These are perspective views and partially enlarged cross-sectional views of the busbar according to the present invention.

[0054] Reference Figure 2 (a) is an overall three-dimensional view of busbar 200, and (b) is a local enlarged cross-sectional view taken along line B'-B” of (a).

[0055] The busbar 200 according to the present invention includes a busbar body 210, which is configured to have a plurality of conductive layers 211 stacked therein, wherein an insulating layer 220 is attached to at least a portion of the outer surface of the busbar body 210. A fusion portion 240 is coupled to both ends of the busbar body 210 to fix the plurality of conductive layers 211.

[0056] The multiple conductive layers 211 are separate layers in a stacked state and are connected to each other only at the fusion portion 240. Specifically, when the ends of the multiple conductive layers 211 are soldered in a stacked state, the fusion portion 240 is formed at the ends of the multiple conductive layers 211 and the ends of the multiple conductive layers are fixed by the fusion portion.

[0057] Multiple conductive layers 211 can be made of the same material as the busbar body of a conventional strip busbar, such as copper, aluminum, or alloys thereof.

[0058] Connecting portions 230 are formed at both ends of the busbar body 210, each connecting portion having a fastening through hole configured to allow fastening members (e.g., bolts) to be inserted therein, and an insulating layer 220 is attached to cover the remaining outer surface of the busbar body 210 except for the connecting portions 230.

[0059] The insulating layer 220 can be configured such that an adhesive layer is applied to a surface of a substrate made of an insulating material, or it can be formed in the shape of a heat-shrinkable tube. The insulating material is not particularly limited, but can be at least one selected from, for example, silicone, polyethylene, polypropylene, rubber, ceramics, polycarbonate, and polybutylene terephthalate.

[0060] The busbar according to the invention is configured such that a plurality of conductive layers are stacked, allowing the busbar to deform freely. At least one through-hole or slit can be formed in at least one of the plurality of conductive layers to increase the flexibility of the conductive layers, allowing them to be easily bent when bending is required depending on the environment in which the busbar is applied. Furthermore, in the plurality of stacked conductive layers, the inner and outer conductive layers in the stacking direction can differ from each other in terms of bending angle and bending direction. For this purpose, the conductive layers can be configured to have different shapes and thicknesses depending on their positions.

[0061] Figure 3 This is an exploded perspective view of the main body of the busbar according to the first embodiment.

[0062] Reference Figure 3 The busbar body 210 is configured such that the plurality of conductive layers 211 have the same shape. Each of the plurality of conductive layers 211 has a through hole of a predetermined size that is uniformly distributed over its entire area at predetermined distances from each other.

[0063] The through-holes formed in each conductive layer 211 improve the ductility of the busbar body 210, allowing the busbar body to be easily deformed.

[0064] Furthermore, if the outer conductive layer bends more than the inner conductive layer when multiple conductive layers 211 are stacked, greater stress may be generated. However, the stress generated when the outer conductive layer bends can be reduced by providing vias.

[0065] In addition, with Figure 3 With different configurations, the vias formed in the multiple conductive layers 211 may not be aligned with each other, but may be offset from each other, which also falls within the scope of the present invention.

[0066] In addition to circular shapes, vias can also have various planar shapes, such as polygonal or elliptical shapes. In a specific example, when slits are formed in multiple conductive layers 211, the slits can extend in a straight line parallel to the length direction.

[0067] Figure 4 This is an exploded perspective view of the main body of the busbar according to the second embodiment.

[0068] Reference Figure 4 In the busbar body 310, each of the plurality of conductive layers 311 is configured in a grid pattern in which the first line 301 and the second line 302 intersect. That is, the plurality of conductive layers 311 can be manufactured in a form in which the first line 301 and the second line 302 are fixed in a grid pattern, and each of the first line 301 and the second line 302 is made of linear conductive metal.

[0069] Similar to Figure 4 The busbar body 310 shown can have multiple conductive layers 311 configured such that the thickness and spacing of the first line 301 and the second line 302 are uniform, thereby forming a structure in which the same conductive layers 311 are stacked.

[0070] Alternatively, with Figure 4 Unlike the busbar body 310 shown, in the stacking direction of the multiple conductive layers 311, the thickness of the first line 301 and the second line 302 can gradually decrease from the innermost conductive layer to the outermost conductive layer, and the spacing between the first line 301 and the second line 302 can gradually increase.

[0071] During bending, greater stress can be applied to the outer conductive layer than to the inner conductive layer in the stacking direction. The outer conductive layer can be configured such that more empty space can be created by reducing the thickness of the first and second lines and increasing the spacing between the first and second lines. This can alleviate the greater stress generated when the outer conductive layer bends, thereby reducing stress deviation between multiple conductive layers and thus preventing separation between conductive layers connected to each other at the fusion point.

[0072] Figure 5This is an exploded perspective view of the main body of the busbar according to the third embodiment.

[0073] Reference Figure 5 Busbar main body 410 and Figure 3 The busbar body 210 shown is similar in that it has vias formed in all of the multiple conductive layers, but the number of vias formed in the multiple conductive layers is similar to that of the busbar body 410. Figure 3 The busbar body 210 shown is different.

[0074] Specifically, among multiple conductive layers, the area of ​​the via or slit gradually increases from the innermost conductive layer to the outermost conductive layer in the stacking direction. Figure 5 Among the conductive layers shown, the innermost conductive layer 411c has the smallest number of vias, the number of vias formed in the conductive layer 411b is greater than the number of vias formed in the conductive layer 411c, and the number of vias formed in the outermost conductive layer 411a is greater than the number of vias formed in the conductive layer 411b.

[0075] As described above, since the outer conductive layer among the multiple conductive layers is formed with a larger number of through holes, when the busbar body 410 is bent, it is possible to prevent the application of greater stress to the outer conductive layer than to the inner conductive layer, and thus prevent the separation of the conductive layers connected to each other at the fusion portion.

[0076] Figure 6 This is an exploded perspective view of the main body of the busbar according to the fourth embodiment.

[0077] Reference Figure 6 The busbar body 510 is configured such that multiple conductive layers 511a, 511b and 511c are stacked, wherein the thickness of the conductive layers gradually decreases from the innermost conductive layer 511c to the outermost conductive layer 511a in the stacking direction.

[0078] In other words, the innermost conductive layer 511c has the largest thickness Dc, the conductive layer 511b located outside the conductive layer 511c has a thickness Db that is less than the thickness Dc, and the outermost conductive layer 511a has a thickness Da that is less than the thickness Db.

[0079] As described above, since the outer conductive layer among the multiple conductive layers is formed to be thinner than the other conductive layers so as to be more flexible, when the busbar body 510 is bent, it is possible to prevent the application of greater stress to the outer conductive layer than to the inner conductive layer, thereby reducing the stress deviation between the multiple conductive layers, and thus preventing the separation of the conductive layers connected to each other at the fusion portion.

[0080] Figure 7 These are perspective and cross-sectional views of the busbar according to the fifth embodiment, and Figure 8 yes Figure 7 A magnified view of a portion of the image.

[0081] Reference Figure 7 and Figure 8 , Figure 7 (a) is a three-dimensional view of busbar 600, and Figure 7 (b) is along Figure 7 A perspective view of a cross-section taken from line C'-C" of (a). Busbar 600 is configured such that busbar 100, formed in the shape of a metal strip (and therefore difficult to deform), is connected to the left side of busbar 200, which is configured to be easily deformable. That is, busbar 600 according to the invention can be configured such that a non-flexible busbar having an insulating layer attached to the outer surface of the metal strip is connected to at least one of the first end and the second end of the busbar body of busbar 200. Therefore, with Figure 7 As shown, busbar 100 can be connected to the right side of busbar 200, or busbar 100 can be connected to each of the two ends of busbar 200.

[0082] Busbar 100 and busbar 200 can be joined together by welding, and thus a weld joint 650 can be formed between busbar 100 and busbar 200.

[0083] A specific configuration in which non-flexible busbars and flexible busbars are connected to each other when forming welded joint 650 may include, for example, a first unit comprising non-flexible busbars and flexible busbars; a second unit comprising non-flexible busbars, flexible busbars and non-flexible busbars; and a third unit comprising flexible busbars, non-flexible busbars and flexible busbars, wherein two or more identical units, two or more different units, or identical and different units may be selected from the first unit to the third unit and may be connected to each other.

[0084] As described above, the hybrid busbar 600, which uses flexible busbars (e.g., busbar 100) and non-flexible busbars (e.g., busbar 200) connected to each other, can obtain both the advantages of the free deformation of the flexible busbar and the advantages of the excellent strength and high conductivity of the non-flexible busbar.

[0085] Furthermore, the present invention provides a battery pack comprising a busbar according to the invention and electrical components connected to the busbar. In the battery pack, the busbar is connected to the electrical components in a state where the busbar is bent to form at least one bend. Since the busbar according to the invention can be freely deformed, the space required to connect the busbar can be minimized regardless of the position and size of the electrical components disposed in the battery pack. Therefore, more battery cells can be disposed in space that would otherwise be wasted due to the use of a non-bent busbar, thus enabling the manufacture of battery packs with higher capacity than conventional battery packs of the same volume.

[0086] Those skilled in the art will understand that, based on the above description, various applications and modifications are possible within the scope of this invention.

[0087] (Explanation of symbols in the attached diagram)

[0088] 100, 200, 600: Busbars

[0089] 110, 210, 310, 410, 510: Busbar main body

[0090] 120, 220: Insulation layer

[0091] 130, 230: Connecting parts

[0092] 211, 311, 411a, 411b, 411c, 511a, 511b, 511c: Conductive layers

[0093] 240: Integration Department

[0094] 301: First Line

[0095] 302: Second Line

[0096] 650: Welded joint

[0097] Da, Db, Dc: Thickness

Claims

1. A busbar, the busbar comprising: Busbar body, the busbar body being configured as a structure having multiple conductive layers stacked on top of each other; A fusion section is connected to both ends of the busbar body to fix the plurality of conductive layers; as well as An insulating layer is attached to at least a portion of the outer surface of the busbar body, wherein... The multiple conductive layers are connected to each other only at the fusion portion.

2. The busbar according to claim 1, wherein, The connecting parts are located at both ends of the busbar body, and fastening through holes are formed in the connecting parts. The insulating layer is attached to cover the remaining outer surface of the busbar body except for the connecting parts.

3. The busbar according to claim 1, wherein, At least one through-hole or slit is formed in at least one of the plurality of conductive layers.

4. The busbar according to claim 3, wherein, The vias or slits are formed in all of the plurality of conductive layers, and all of the conductive layers are formed in the same shape.

5. The busbar according to claim 3, wherein, The via or the slit is formed in all of the plurality of conductive layers, and Among the plurality of conductive layers, the area of ​​the via or the slit gradually increases from the innermost conductive layer to the outermost conductive layer.

6. The busbar according to claim 1, wherein, Each of the plurality of conductive layers is configured as a grid pattern in which the first line and the second line intersect.

7. The busbar according to claim 6, wherein, The plurality of conductive layers are configured such that the thickness and spacing of the first line and the second line are constant.

8. The busbar according to claim 6, wherein, Among the plurality of conductive layers, the thickness of the first line and the second line gradually decreases from the innermost conductive layer to the outermost conductive layer, and the spacing between the first line and the spacing between the second line gradually increases from the innermost conductive layer to the outermost conductive layer.

9. The busbar according to claim 1, wherein, Among the plurality of conductive layers, the thickness of the conductive layer gradually decreases from the innermost conductive layer to the outermost conductive layer.

10. The busbar according to claim 1, wherein, The fusion section is formed by welding to attach and fix the ends of the plurality of conductive layers.

11. The busbar according to claim 1, wherein, A non-flexible busbar having an insulating layer attached to the outer surface of a metal strip is connected to at least one of a first end and a second end of the busbar body.

12. A battery pack, the battery pack comprising: Busbar according to any one of claims 1 to 11; as well as Electrical components, wherein the busbar is connected to the electrical components, wherein, The busbar is connected to the electrical component in a state where the busbar is bent to form at least one bend.

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