Battery module including cell frame with integrated busbars

Abstract

The present invention relates to a battery module including a plurality of battery cells, a cell frame accommodating the plurality of battery cells, bus bars connecting the plurality of battery cells in series and / or parallel, and bonding wires electrically connecting the battery cells and the bus bars, wherein the bus bars include one or more first bus bars located on an upper portion of the cell frame and two second bus bars located on both side surfaces of the cell frame, and the cell frame and the bus bars are integrally formed by insert injection molding.

Description

[Technical Field]

[0001] This application claims the benefit of priority based on Korean Patent Application No. 2021-0147743 dated November 1, 2021, and all contents disclosed in the documents of that Korean patent application are incorporated herein by reference.

[0002] The present invention relates to a battery module including a busbar-integrated cell frame in which the busbar and the cell frame are integrally formed to prevent loose movement and separation of the busbar. [Background technology]

[0003] As technological developments and demand for mobile devices such as smartphones, notebook PCs, and digital cameras increase, technologies related to rechargeable secondary batteries are being actively developed. Secondary batteries are an alternative energy source to fossil fuels, which generate air pollutants, and are used in electric vehicles (EVs), hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (P-HEVs), and energy storage devices (ESSs).

[0004] Currently widely used types of secondary batteries include lithium-ion batteries, lithium polymer batteries, nickel-cadmium batteries, nickel-metal hydride batteries, and nickel-zinc batteries. The operating voltage of such unit secondary battery cells, i.e., unit battery cells, is approximately 2.0V to 5.0V. Therefore, if a higher output voltage is required, a cell module assembly can be constructed by connecting multiple battery cells in series, or a battery module can be constructed by connecting cell module assemblies in series or parallel depending on the required output voltage or charge / discharge capacity. Thus, it is common to manufacture a battery pack by adding additional components using at least one battery module.

[0005] A method for manufacturing such a battery pack includes a step of fixing bus bars to the cell frames to connect battery cells housed in the cell frames in series and / or parallel, and a step of electrically connecting the bus bars to the battery cells by wire bonding, welding, or other methods as disclosed in Patent Document 1.

[0006] However, if the bus bar is not fixed to the cell frame, damage may occur at the portion where the battery cell and the bus bar are joined by a method such as wire bonding or welding.

[0007] Therefore, in order to fix the bus bar to the cell frame, conventionally, adhesive is applied to the frame on which the bus bar is to be seated, and after the bus bar is seated, a process is carried out in which the adhesive is cured.

[0008] However, this conventional method involves complicated processes and has the problem that the busbars may move or separate due to improper application or hardening of the adhesive. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] Korean Patent Publication No. 10-2019-0067326 Summary of the Invention [Problem to be solved by the invention]

[0010] In order to solve the above problems, an object of the present invention is to provide a busbar-integrated cell frame that can eliminate a process for bonding the busbar by integrally forming the busbar and the cell frame, and a battery module including the same.

[0011] Another object of the present invention is to provide a busbar-integrated cell frame capable of preventing loose movement and separation of the busbars, and a battery module including the same. [Means for solving the problem]

[0012] In order to achieve the above object, the battery module according to the present invention includes a plurality of battery cells (100), a cell frame (200) that houses the plurality of battery cells (100), bus bars (300) that connect the plurality of battery cells (100) in series and / or parallel, and bonding wires (400) that electrically connect the battery cells (100) and the bus bars (300), wherein the bus bars (300) include one or more first bus bars (310) located on an upper portion of the cell frame (200) and two second bus bars (320) located on both sides of the cell frame (200), and the cell frame (200) and the bus bars (300) are formed integrally by insert injection molding.

[0013] In the battery module according to the present invention, the battery cells (100) are cylindrical battery cells (100).

[0014] In addition, in the battery module according to the present invention, the second bus bar (320) includes a first surface (321) located on the same plane as the first bus bar (310), a second surface (322) connected to the first surface (321) in a bent state and located on a side surface of the cell frame (200), and a third surface (323) connected to the second surface (322) in a bent state and located on a front surface of the cell frame (200).

[0015] In addition, in the battery module according to the present invention, the second surfaces (322) of the first bus bar (310) and the second bus bar (320) are provided with a first through hole (311) and a second through hole (324), respectively.

[0016] In addition, in the battery module according to the present invention, the first through-holes (311) and the second through-holes (324) are provided in plurality at a predetermined distance apart on the second surfaces (322) of the first bus bar (310) and the second bus bar (320), respectively, and are filled with a resin component forming the cell frame (200).

[0017] In addition, in the battery module according to the present invention, a first pin insertion hole (312) is formed in the first bus bar (310) and a second pin insertion hole (325) is formed in the first surface (321) of the second bus bar (320) so that the first bus bar (310) and the second bus bar (320) can be fixed together during the insert injection molding.

[0018] In addition, in the battery module according to the present invention, the cell frame (200) has a band shape that covers the upper part of the first bus bar (310) and the second bus bar (320) with a certain width along the width direction of the first bus bar (310) and the second bus bar (320), and includes a plurality of fixing portions (210) that fix the first bus bar (310) and the second bus bar (320).

[0019] In addition, in the battery module according to the present invention, the fixing part (210) is characterized in that pin holes (211) are formed at positions corresponding to the first pin insertion hole (312) and the second pin insertion hole (325).

[0020] In addition, in the battery module according to the present invention, an electrode terminal (330) in the form of a self-clinching stud is coupled to the third surface (323) so as to be fastened to a power connector.

[0021] In the battery module according to the present invention, the power connector is a flange nut.

[0022] The present invention also provides a method for manufacturing the battery module, comprising: a) integrally forming the bus bar (300) and the cell frame (200) by insert injection molding; b) accommodating the plurality of battery cells (100) in the cell frame (200) formed integrally with the bus bar (300); and c) electrically connecting the battery cells (100) and the bus bar (300) with the bonding wires (400).

[0023] The present invention also provides a battery pack including the above-mentioned battery module. [Effects of the Invention]

[0024] The battery module of the present invention has an advantage that the bus bar and the cell frame are integrally formed by insert injection molding, thereby eliminating the step of adhering the bus bar.

[0025] In addition, the battery module of the present invention has the advantage that loose movement and separation of the bus bars can be prevented by filling the through holes formed in the bus bars with a resin component that constitutes the cell frames to form an integrated structure. [Brief explanation of the drawings]

[0026] [Figure 1] 1 is a perspective view of a battery module according to an embodiment of the present invention; [Figure 2] FIG. 2 is a partially enlarged view of the battery module shown in FIG. [Figure 3] FIG. 2 is a perspective view of a first bus bar according to an embodiment of the present invention. [Figure 4] FIG. 4 is a perspective view of a second bus bar according to an embodiment of the present invention. [Figure 5] 1A and 1B are a plan view and a cross-sectional view, respectively, schematically illustrating a shape in which a first bus bar is fixed to a cell frame according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0027] In this application, the terms "comprises," "has," or "has" are intended to specify the presence of features, numbers, steps, components, parts, or combinations thereof described in the specification, but should be understood as not precluding the possibility of the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

[0028] Furthermore, 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 not only a direct connection but also an indirect connection via another element therebetween. Furthermore, unless otherwise specified, "including a certain element" does not mean that other elements are excluded, but that other elements may also be included.

[0029] Hereinafter, a battery module according to the present invention will be described with reference to the accompanying drawings.

[0030] FIG. 1 is a perspective view of a battery module according to an embodiment of the present invention, FIG. 2 is a partially enlarged view of the battery module shown in FIG. 1, FIG. 3 is a perspective view of a first bus bar according to an embodiment of the present invention, and FIG. 4 is a perspective view of a second bus bar according to an embodiment of the present invention.

[0031] A battery module 1000 of the present invention will be described with reference to FIGS. 1 to 4. The battery module 1000 includes a battery cell 100, a cell frame 200, a bus bar 300, and a bonding wire 400.

[0032] Although the bonding wire 400 is omitted in FIG. 1, the enlarged view of FIG. 2 shows in detail the shape of the battery cell 100 and the bus bar 300 electrically connected by the bonding wire 400.

[0033] A plurality of battery cells 100 are provided in the battery module 1000, and various types of battery cells 100 may be applied.

[0034] The battery cell 100 can be roughly classified according to the type of case into a can type in which the electrode assembly is housed in a metal can, and a pouch type in which the electrode assembly is housed in a pouch having a laminate sheet structure.

[0035] Can-type battery cells can include cylindrical batteries and prismatic batteries, which are generally classified according to the shape of the metal can.

[0036] A cylindrical secondary battery may include a cylindrical battery can, a jelly-roll-shaped electrode assembly housed inside the battery can, and a cap assembly attached to the top of the battery can. Here, the cylindrical battery can may be made of a lightweight conductive metal material such as aluminum, stainless steel, or an alloy thereof.

[0037] Although the present invention has been described with reference to a cylindrical battery cell 100, the scope of the present invention is not limited thereto.

[0038] The cell frame 200 is a structure that houses a plurality of battery cells 100, and bus bars 300 are seated on the top and side corners, and the cell frame 200 houses the battery cells 100 inside.

[0039] Such a cell frame 200 includes a fixing portion 210 and a pinhole 211 for fixing the bus bar 300 to be seated thereon.

[0040] Here, the fixing portion 210 has a band shape that covers the upper portion of the first bus bar 310 and the second bus bar 320 with a certain width along the width direction of the first bus bar 310 and the second bus bar 320. That is, the fixing portion 210 is not formed over the entire upper portion of the first bus bar 310 and the second bus bar 320, but is formed at a certain distance apart, so that a certain portion of the upper portion of the first bus bar 310 and the second bus bar 320 is exposed.

[0041] Meanwhile, the bus bars 300 include one or more first bus bars 310 located on the top of the cell frame 200 and two second bus bars 320 located on both sides of the cell frame 200 .

[0042] The bus bar 300 is made of a metal material having excellent electrical conductivity, and the width and thickness of the bus bar 300 can be appropriately selected depending on the structure of the battery module 1000.

[0043] The first bus bar 310 includes a first through hole 311 that is filled with the resin component that forms the cell frame 200 during insert injection molding, and a first pin insertion port 312 into which a mold pin that is used to fix the first bus bar 310 during insert injection molding is inserted.

[0044] The second bus bar 320 includes a first surface 321 located on the same plane as the first bus bar 310, a second surface 322 connected to the first surface 321 in a bent state and located on the side of the cell frame 200, and a third surface 323 connected to the second surface 322 in a bent state and located on the front surface of the cell frame 200.

[0045] First surface 321 is formed with second pin insertion opening 325 which serves the same function as first pin insertion opening 312 of first bus bar 310, and second surface 322 is formed with second through hole 324.

[0046] An electrode terminal 330 is coupled to the third surface 323 to electrically connect the battery module 1000 to the outside.

[0047] The electrode terminal 330 has the form of a self-clinching stud and is fixed by being pressed into a hole formed in the third surface 323 of the second bus bar 320, and the second bus bar 320 to which the electrode terminal 330 is fixed is formed integrally with the cell frame 200 by insert injection molding as described above.

[0048] A power connector is connected to the electrode terminal 330, thereby electrically connecting the electrode terminal 330 to the outside.

[0049] Meanwhile, the electrode terminal 330 may have a threaded shape or a straight line shape without a thread. In the case of the electrode terminal 330 having a threaded shape, it is preferable that the power connector also has a flange nut shape in terms of a firm fastening.

[0050] Of course, the electrode terminals 330 may be pressed into the second bus bar 320 in the form of self-clinching studs, but are not limited thereto, and may also be formed integrally with the second bus bar 320.

[0051] The reason why the fixing portion 210 of the cell frame 200 is formed as described above is that an exposed area of ​​the bus bar 300 is required on the top of the bus bar 300 to which the bonding wire 400 for electrical connection with the battery cell 100 can be bonded.

[0052] Furthermore, the cell frame 200 of the present invention is formed integrally with the bus bar 300 by insert injection molding, and in this process it is necessary to fix the bus bar 300 so that it does not come off from its fixed position.

[0053] Therefore, in the present invention, bus bar 300 is fixed using a mold pin, and after the resin component is hardened by insert injection molding, pinhole 211 is formed at the position where the mold pin was removed.

[0054] FIG. 5 is a schematic diagram showing a shape in which a first bus bar is fixed to a cell frame according to an embodiment of the present invention, with FIG. 5(a) being a plan view and FIG. 5(b) being a cross-sectional view.

[0055] A structure for fixing first bus bars 310 and cell frame 200 according to an embodiment of the present invention will be described with reference to Fig. 5. As described above, each of first bus bars 310 has a plurality of first through holes 311 formed at a predetermined distance apart, and during insert injection molding, the resin component forming cell frame 200 fills first through holes 311, connects with fixing parts 210 on the top of first bus bars 310, and hardens, thereby fixing first bus bars 310 to cell frame 200.

[0056] Figure 5 uses the first bus bar 310 as an example, but the second through hole 324 of the second bus bar 320 can also be filled with a resin component, just like the first through hole 311, thereby fixing the second bus bar 320 to the cell frame 200.

[0057] A method for manufacturing the battery module 1000 of the present invention will be described below.

[0058] A manufacturing method of the battery module 1000 according to the present invention includes the steps of: a) integrally forming the bus bar 300 and the cell frame 200 by an insert injection molding method; b) accommodating the plurality of battery cells 100 in the cell frame 200 formed integrally with the bus bar 300; and c) electrically connecting the battery cells 100 and the bus bar 300 with bonding wires 400.

[0059] Here, prior to step a), the step of preparing the bus bar 300 may further include the steps of forming the first through hole 311, the first pin insertion hole, the second through hole 324, and the second pin insertion hole 325 in each of the first bus bar 310 and the second bus bar 320, and coupling the electrode terminal 330 to the second bus bar 320.

[0060] The first through hole 311, the first pin insertion opening 324, and the second pin insertion opening 325 may be formed in the first bus bar 310 and the second bus bar 320, respectively, by forming the bus bars 310 and 320 without the through holes 311 and 324 and the pin insertion openings 312 and 325, and then forming the through holes 311 and 324 and the pin insertion openings 312 and 325. Alternatively, the through holes 311 and 324 and the pin insertion openings 312 and 325 may be formed integrally during the process of forming the bus bars 310 and 320.

[0061] Meanwhile, the step of integrally forming the bus bar 300 using the insert injection molding method includes the steps of positioning and fixing the prepared bus bar 300 in a mold, melting the resin that will form the cell frame 200 and injecting it into the mold, and cooling and hardening the resin to manufacture the cell frame 200 integrally formed with the bus bar 300.

[0062] Furthermore, after the step c), a step of housing the device in a module case and a step of connecting various circuits may be added.

[0063] In this way, by applying the cell frame 200 integrally formed with the bus bar 300 manufactured using the bus bar 300 of the present invention to the manufacturing process, the process of bonding the bus bar 300 to the cell frame 200 can be omitted from the manufacturing process of the battery module 1000, which is expected to reduce the manufacturing steps and time, and thereby reduce manufacturing costs.

[0064] In addition, various defects caused by the bus bar 300 being separated or moving loosely can be prevented.

[0065] The battery module 1000 manufactured in this manner can be manufactured independently or in the form of a battery pack and used as a power source for various devices.

[0066] Although specific portions of the present invention have been described in detail above, it will be apparent to those skilled in the art that such specific techniques are merely preferred embodiments and do not limit the scope of the present invention. It is possible to make various changes and modifications within the scope and technical spirit of the present invention, and it goes without saying that such changes and modifications are also included in the scope of the appended claims. [Explanation of symbols]

[0067] 1000 Battery Module 100 battery cells 200 cell frames 210 Fixed part 211 Pinhole 300 Busbar 310 First bus bar 311 First Through Hole 312 First pin insertion port 320 Second bus bar 321 Page 1 322 2nd page 323 3rd page 324 Second Through Hole 325 Second pin insertion port 330 Electrode terminal 400 Bonding Wire

Claims

1. a plurality of battery cells; a cell frame that houses the plurality of battery cells; a bus bar that connects the plurality of battery cells in series and / or parallel; a bonding wire electrically connecting the battery cell and the bus bar; A battery module comprising: the bus bars include one or more first bus bars positioned on an upper portion of the cell frame and two second bus bars positioned on both side surfaces of the cell frame; the cell frame and the bus bar are integrally formed by insert injection molding, the second bus bar includes a second surface located on a side surface of the cell frame and a third surface located on a front surface of the cell frame, The battery module has electrode terminals coupled to the third surface for electrically connecting the battery module to an external device.

2. The battery module according to claim 1 , wherein the battery cells are cylindrical battery cells.

3. the second bus bar has a first surface that is flush with the first bus bar; the second surface being connected to the first surface in a folded state and positioned on a side surface of the cell frame; the third surface being connected to the second surface in a folded state and positioned on a front surface of the cell frame; The battery module of claim 1 , comprising:

4. The battery module of claim 3 , wherein the second surface of the first bus bar and the second surface of the second bus bar are provided with a first through-hole and a second through-hole, respectively.

5. 5. The battery module of claim 4, wherein the first through holes and the second through holes are provided in plurality at a predetermined distance on the second surface of the first bus bar and the second surface of the second bus bar, and are filled with a resin component that forms the cell frame.

6. 4. The battery module of claim 3, wherein a first pin insertion hole is formed in the first bus bar and a second pin insertion hole is formed in a first surface of the second bus bar, such that the first bus bar and the second bus bar can be fixed together during the insert injection molding.

7. 7. The battery module of claim 6, wherein the cell frame has a band shape that covers an upper portion of the first bus bar and the second bus bar with a certain width along a width direction of the first bus bar and the second bus bar, and includes a plurality of fixing portions that fix the first bus bar and the second bus bar.

8. The battery module according to claim 7 , wherein the fixing portion has pinholes formed at positions corresponding to the first pin insertion opening and the second pin insertion opening.

9. The battery module according to claim 3 , wherein the electrode terminal is a self-clinching stud coupled to the third surface so as to be fastened to a power connector.

10. The battery module according to claim 9 , wherein the power connector is a flange nut.

11. A method for manufacturing the battery module according to any one of claims 1 to 10, comprising: a) integrally forming the cell frame of the bus bar by insert injection molding; b) housing the plurality of battery cells in the cell frame integrally formed with the bus bar; c) electrically connecting the battery cell and the bus bar with the bonding wire; A battery module manufacturing method comprising:

12. A battery pack comprising the battery module according to any one of claims 1 to 10.

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