Battery module manufacturing method using vibration jig and battery module manufactured using the same

Abstract

The present invention relates to a method for manufacturing a battery module by filling a module case (200) in which a plurality of battery cells (100) are stored at a certain distance apart with a glue (300), comprising: a) storing the plurality of battery cells (100) in the module case (200); b) attaching a bus bar to the module case (200); c) electrically connecting the bus bar to the plurality of battery cells (100); d) fixing the module case (200) to a vibration jig (400); e) positioning a device (500) for injecting the glue (300) on the upper part of the module case; f) applying the glue (300) to the upper part of the module case (200); g) vibrating the module case (200); and h) curing the glue (300).

Description

Technology Field

[0001] The present invention relates to a method for manufacturing a battery module that can improve the charging speed of glue and charge it uniformly using a vibrating jig, and a battery module manufactured using the same. Background Technology

[0003] With the increasing technological development and demand for mobile devices such as smartphones, laptops, and digital cameras, technologies related to rechargeable secondary batteries are becoming more active. Furthermore, secondary batteries are being applied to electric vehicles (EVs), hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (P-HEVs), and energy storage devices (ESS) as alternative energy sources to fossil fuels that cause air pollutants.

[0004] Currently, widely used types of rechargeable batteries include lithium-ion batteries, lithium-polymer batteries, nickel-cadmium batteries, nickel-hydrogen batteries, and nickel-zinc batteries.

[0005] The operating voltage of these unit secondary battery cells, that is, unit battery cells, is approximately 2.0V to 5.0V. Therefore, if a higher output voltage is required, multiple battery cells may be connected in series to form a cell module assembly, and cell module assemblies may also be connected in series or parallel according to the required output voltage or charge / discharge capacity to form a battery module, and it is common to manufacture a battery pack by adding additional components using at least one of these battery modules.

[0006] When manufacturing such battery modules, particularly using cylindrical battery cells, the process of filling the module with glue may also be included.

[0007] The glue filling process typically involves applying an adhesive composition to fill and then curing it.

[0008] FIGS. 1 and FIGS. 2 are cross-sectional views schematically illustrating a conventional glue filling process.

[0009] Referring to FIGS. 1 and FIGS. 2, a conventional glue filling process is described as follows: first, a plurality of battery cells (10) are housed in a module case (20), and although not shown in the drawings, a bus bar is placed and then the battery cells (10) and the bus bar are joined.

[0010] Afterwards, as shown in FIG. 1, if glue (30) is applied to the entire upper part using an injection device (40) from the upper part, it is filled inward as shown in FIG. 2.

[0011] However, the glue (30) has a certain level of viscosity even before curing, so it takes a long time to be fully filled to the bottom, and as shown in Fig. 2, it is not fully filled to the end and there is a problem of empty space (S) occurring.

[0012] In fact, as shown in FIG. 3, when examining the glue filling state within the battery module after filling the glue into the battery module using a conventional method, it can be seen that the glue is not filled in a part of the lower section and an empty space (S) is formed.

[0013] To compensate for this, there is a method to widen the spacing between battery cells, but in this case, there is a problem of reduced energy density. The problem to be solved

[0015] The present invention aims to provide a method for manufacturing a battery module by applying a vibrating jig in a glue filling process to solve the above-mentioned problems, and a battery module manufactured using the same. means of solving the problem

[0017] A battery module manufacturing method according to the present invention for achieving the above-mentioned purpose is a method for manufacturing a battery module by filling a module case (200) in which a plurality of battery cells (100) are stored at a certain distance apart with a glue (300), and is characterized by comprising: a) a step of storing the plurality of battery cells (100) in the module case (200); b) a step of attaching a bus bar to the module case (200); c) a step of electrically connecting the bus bar and the plurality of battery cells (100); d) a step of fixing the module case (200) to a vibration jig (400); e) a step of positioning a glue (300) injection device (500) on the upper part of the module case; f) a step of applying the glue (300) to the upper part of the module case (200); g) a step of vibrating the module case (200); and h) a step of curing the glue (300).

[0018] In addition, in the method for manufacturing a battery module according to the present invention, the battery cell (100) is characterized as being a cylindrical battery cell (100).

[0019] In addition, in the method for manufacturing a battery module according to the present invention, step c) is characterized as a step of joining the bus bar and the plurality of battery cells (100) using welding or wire bonding.

[0020] In addition, the battery module manufacturing method according to the present invention is characterized in that step f) and step g) are performed simultaneously.

[0021] In addition, in the method for manufacturing a battery module according to the present invention, the glue (300) is characterized by comprising an adhesive resin, a curing agent, and silica beads.

[0022] In addition, in the method for manufacturing a battery module according to the present invention, the adhesive resin is characterized as being an epoxy resin or an acrylic resin.

[0023] In addition, the battery module manufacturing method according to the present invention is characterized in that the glue (300) is cured by ultraviolet light or heat.

[0024] In addition, in the method for manufacturing a battery module according to the present invention, step f) is characterized by applying the glue (300) until it is filled inside the module case (200) and covers the bus bar.

[0025] In addition, in the method for manufacturing a battery module according to the present invention, step g) is characterized by vibrating the module case (200) back and forth and left and right.

[0026] In addition, the battery module according to the present invention is characterized by being manufactured using the aforementioned battery module manufacturing method.

[0027] In addition, the present invention is characterized by providing a battery pack including the aforementioned battery module. Effects of the invention

[0029] The battery module manufacturing method of the present invention has the advantage of being able to improve the charging speed of the glue by using a vibrating jig, thereby shortening the process time.

[0030] In addition, the battery module manufacturing method of the present invention has the advantage of being able to manufacture a battery module that is uniformly charged to the bottom without any uncharged parts of the glue. Brief explanation of the drawing

[0032] Figure 1 is a schematic diagram showing a charging process in which glue is applied to the top of a conventional battery module. FIG. 2 is a schematic diagram showing the shape of glue filled inside a conventional battery module. Figure 3 is an actual image showing the glue charging state inside the battery module after charging the glue using a conventional method. FIG. 4 is a schematic diagram illustrating a process of filling a battery module with glue using a vibrating jig according to one embodiment of the present invention. FIG. 5 is a schematic diagram showing the shape of a battery module filled with glue according to one embodiment of the present invention. Specific details for implementing the invention

[0033] In this application, terms such as “comprising,” “having,” or “having” are intended to specify the existence of the features, numbers, steps, components, parts, or combinations thereof described in the specification, and should be understood as not precluding the existence or addition of one or more other features, numbers, steps, actions, components, parts, or combinations thereof.

[0034] In addition, the same reference numerals are used for parts having similar functions and operations throughout the drawings. Throughout the specification, when a part is described as being connected to another part, this includes not only cases where they are directly connected, but also cases where they are indirectly connected with other elements in between. Furthermore, unless specifically stated otherwise, the inclusion of a certain component does not exclude other components but implies that additional components may be included.

[0036] Hereinafter, a method for manufacturing a battery module according to the present invention will be described with reference to the attached drawings.

[0037] FIG. 4 is a schematic diagram showing a process of filling a battery module with glue using a vibrating jig according to one embodiment of the present invention, and FIG. 5 is a schematic diagram showing the shape of a battery module filled with glue according to one embodiment of the present invention.

[0038] Referring to FIGS. 4 and 5, the battery module manufacturing method of the present invention comprises: a) a step of housing a plurality of battery cells (100) in a module case (200); b) a step of coupling a bus bar to the module case (200); c) a step of electrically connecting the bus bar to the plurality of battery cells (100); d) a step of fixing the module case (200) to a vibration jig (400); e) a step of positioning a glue (300) injection device (500) on the upper part of the module case; f) a step of applying the glue (300) to the upper part of the module case (200); g) a step of vibrating the module case (200); and h) a step of curing the glue (300).

[0039] Here, the battery cells (100) housed inside the module case (200) are provided in multiple quantities within the module case (200), and various types of battery cells (100) can be applied.

[0040] Battery cells can be broadly classified according to the shape of the case into a can type, in which the electrode assembly is embedded in a metal can, and a pouch type, in which it is embedded in a pouch made of a laminated sheet structure.

[0041] Can-type battery cells may include cylindrical cells and prismatic cells, which are generally classified according to the shape of the metal can.

[0042] A cylindrical secondary battery may include a cylindrical battery can, a jelly-roll type electrode assembly accommodated inside the battery can, and a cap assembly coupled to the top of the battery can. Here, the cylindrical battery can may be formed from a lightweight conductive metal material such as aluminum, stainless steel, or an alloy thereof.

[0043] The electrode assembly is manufactured by alternately stacking electrodes and separators, and the electrode is formed by applying an electrode active material onto an electrode current collector.

[0044] Electrode active materials can be divided into positive electrode active materials and negative electrode active materials, and a slurry is prepared by adding a conductive material and a binder to these active materials and then coated onto a metal foil.

[0045] The positive electrode active material is a layered compound such as lithium cobalt oxide (LiCoO2) or lithium nickel oxide (LiNiO2), or a compound substituted with one or more transition metals; chemical formula Li 1+x Mn 2-x Lithium manganese oxides such as O4 (where x is 0 to 0.33), LiMnO3, LiMn2O3, LiMnO2, etc.; lithium copper oxide (Li2CuO2); vanadium oxides such as LiV3O8, LiFe3O4, V2O5, Cu2V2O7, etc.; chemical formula LiNi 1-x M x Ni-site type lithium nickel oxide represented by O2 (where M = Co, Mn, Al, Cu, Fe, Mg, B, or Ga, and x = 0.01 ~ 0.3); chemical formula LiMn 2-x M x Examples include lithium manganese complex oxides represented by O2 (where M = Co, Ni, Fe, Cr, Zn or Ta and x = 0.01 to 0.1) or Li2Mn3MO8 (where M = Fe, Co, Ni, Cu or Zn); LiMn2O4 in which part of the Li in the chemical formula is substituted with alkaline earth metal ions; disulfide compounds; Fe2(MoO4)3, but are not limited to these.

[0046] The conductive material is typically added in an amount of 1 to 30 weight percent based on the total weight of the mixture containing the positive active material.

[0047] Such conductive materials are not particularly limited as long as they possess conductivity without causing chemical changes in the battery, and for example, graphite such as natural graphite or artificial graphite; carbon black such as carbon black, acetylene black, Ketjen black, channel black, furnace black, lamp black, or thermal black; conductive fibers such as carbon fibers or metal fibers; metal powders such as carbon fluoride, aluminum, or nickel powder; conductive whiskey such as zinc oxide or potassium titanate; conductive metal oxides such as titanium oxide; or conductive materials such as polyphenylene derivatives may be used.

[0048] A binder is a component that assists in the bonding of the active material and the conductive material, as well as in the bonding to the current collector, and is typically added in an amount of 1 to 30 weight percent based on the total weight of the mixture containing the positive active material. Examples of such binders include polyvinylidene fluoride, polyvinyl alcohol, carboxymethylcellulose (CMC), starch, hydroxypropylcellulose, regenerated cellulose, polyvinylpyrrolidone, tetrafluoroethylene, polyethylene, polypropylene, ethylene-propylene-diene terpolymer (EPDM), sulfonated EPDM, styrene-butylene rubber, fluororubber, and various copolymers.

[0049] As a negative electrode active material, for example, carbon such as non-graphitizable carbon, graphite-based carbon; Li x Fe2O3(0≤x≤1), Li x WO2(0≤x≤1), Sn x Me 1-x Me y O z(Me: Mn, Fe, Pb, Ge; Me': Al, B, P, Si, Group 1, 2, and 3 elements of the periodic table, halogens; 0 <x≤1; 1≤y≤3; 1≤z≤8) 등의 금속 복합 산화물; 리튬 금속; 리튬 합금; 규소계 합금; 주석계 합금; SnO, SnO2, PbO, PbO2, Pb2O3, Pb3O4, Sb2O3, Sb2O4, Sb2O5, GeO, GeO2, Bi2O3, Bi2O4, Bi2O5등의 금속 산화물; 폴리아세틸렌 등의 도전성 고분자; Li-Co-Ni 계 재료; Si, SiO, SiO2단독 또는 이들의 혼합물인 Si계 등을 사용할 수 있으나, 이들만으로 한정되는 것은 아니다.

[0050] In addition, the cathode active material may also be manufactured by optionally including the above conductive material, binder, etc.

[0051] In the present invention, the battery cell (100) is described on the premise that it is a cylindrical battery cell (100) among the various battery cells (100) described above, but it is not limited thereto and various battery cells (100) can be applied.

[0052] These cylindrical battery cells (100) are stored at a certain distance apart within a module case (200) for reasons such as suppressing heat transfer with neighboring battery cells (100) and preventing the spread of fire.

[0053] Accordingly, a void space is formed between the battery cells (100), and glue (300) is filled to prevent the battery cells (100) from flowing.

[0054] This glue (300) fixes the cylindrical battery cells (100) by going through a process of charging the liquid glue (300) between the cylindrical battery cells (100) and then curing it.

[0055] This glue (300) is a composition including an adhesive resin, a curing agent, and silica beads, etc. As the adhesive resin, epoxy resin or acrylic resin may be used, but is not limited thereto and various known resins may be applied.

[0056] However, it is not desirable to use a thermally conductive adhesive, which is commonly used in the manufacture of conventional battery modules, in order to suppress heat transfer between cylindrical battery cells (100).

[0057] A hardener is a component for hardening the glue (300), and various hardeners can be used depending on the hardening method.

[0058] In addition, other components such as dispersants and defoaming agents may be added to the glue (300) as needed.

[0059] The method of curing the glue (300) may involve irradiating with ultraviolet light and curing by heating, but is not limited to these methods and various known curing methods may be used.

[0060] The reason silica beads are added to the glue (300) is that the silica beads absorb heat and play a role in suppressing heat transfer and ignition.

[0061] Meanwhile, the bus bar is intended to electrically connect multiple battery cells in series and / or parallel, and is formed from a metal material with excellent electrical conductivity; the width and thickness of the bus bar can be appropriately selected according to the structure of the battery module.

[0062] After being mounted in a module case, these bus bars are electrically connected to multiple battery cells through methods such as welding or wire bonding.

[0063] Next, referring to FIG. 4, regarding the vibration jig (400) used in the manufacturing method of the present invention, the vibration jig (400) includes a fixing part (410) that fixes the mounted module case (200) and vibrates the mounted module case (200) in a horizontal direction.

[0064] Here, the horizontal direction refers to the direction in which the module case (200) is parallel to the bottom surface, that is, the front-back and left-right directions.

[0065] In this way, by vibrating the module case (200) in the forward, backward, left, and right directions, the filling speed of the glue (300) can be increased to shorten the process time, and as shown in FIG. 5, it can be filled uniformly to the bottom.

[0066] In addition, the glue (300) uniformly filled between the cylindrical battery cells (100) serves to fix the cylindrical battery cells (100) so that they do not move, and also serves to suppress heat transfer and fire between the cylindrical battery cells (100).

[0067] Various known methods can be applied to vibrate the vibration jig (400), and the magnitude of the vibration, i.e., the amplitude, is not specifically limited but can be appropriately selected within a range where the internal cylindrical battery cell (100) is not displaced or damaged by the vibration.

[0068] The injection device (500) is a device for supplying glue (300) into the module case (200) and may include a storage part for storing glue (300), a nozzle for applying, etc.

[0069] Meanwhile, in the battery module manufacturing method of the present invention, step f) of applying glue (300) to the upper part of the module case (200) is a step of applying glue (300) until the glue is filled between the cylindrical battery cells (100) inside the module case (200) and completely covers the bus bar joined to the cylindrical battery cells (100).

[0070] By applying the glue (300) in this way, it becomes possible to fix not only the cylindrical battery cell (100) but also the bus bar.

[0071] Additionally, step f) of applying glue (300) to the upper part of the module case (200) and step g) of vibrating the module case (200) may be performed continuously or simultaneously.

[0072] The battery module manufactured in this way can be produced either alone or in the form of a battery pack and used as a power source for various devices.

[0074] As specific parts of the present invention have been described in detail above, it is obvious to those skilled in the art that such specific descriptions are merely preferred embodiments and do not limit the scope of the invention, and that various changes and modifications are possible within the scope and spirit of the invention, and that such variations and modifications fall within the scope of the appended claims. Explanation of the symbols

[0076] 100 : Battery cell 200 : Module case 300 : Glue 400: Vibration jig 410 : Fixed part 500: Injection device

Claims

Claim 1 A method for manufacturing a battery module by filling a module case in which a plurality of battery cells are stored spaced apart at a certain distance with glue, comprising: a) storing the plurality of battery cells in the module case; b) attaching a bus bar to the module case; c) electrically connecting the bus bar and the plurality of battery cells; d) fixing the module case to a vibration jig; e) positioning a glue injection device on the upper part of the module case; f) applying the glue in liquid form to the upper part of the module case; g) vibrating the module case; and h) curing the glue; wherein the vibration jig includes a fixing part (410) for fixing the mounted module case, and vibrates the mounted module case in a horizontal direction. Claim 2 A method for manufacturing a battery module according to claim 1, wherein the battery cell is a cylindrical battery cell. Claim 3 A method for manufacturing a battery module according to claim 1, wherein step c) is a step of joining the bus bar and the plurality of battery cells using welding or wire bonding. Claim 4 A method for manufacturing a battery module according to claim 1, wherein step f) and step g) are performed simultaneously. Claim 5 A method for manufacturing a battery module according to claim 1, wherein the glue (300) comprises an adhesive resin, a curing agent, and silica beads. Claim 6 A method for manufacturing a battery module according to claim 5, wherein the adhesive resin is an epoxy resin or an acrylic resin. Claim 7 A method for manufacturing a battery module according to claim 5, wherein the glue is cured by ultraviolet rays or heat. Claim 8 A method for manufacturing a battery module according to claim 1, wherein step f) is characterized by applying the glue until it fills the inside of the module case and covers the bus bar. Claim 9 A method for manufacturing a battery module according to claim 1, wherein step g) is characterized by vibrating the module case back and forth and left and right. Claim 10 delete Claim 11 delete

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