Adhesive layer coating unit, electrode assembly manufacturing apparatus including the same, and electrode assembly manufacturing method

Abstract

The present application provides an adhesive layer coating unit configured to continuously apply an adhesive layer having a first width in a longitudinal direction of a first separator. The adhesive layer coating unit includes a transfer roller configured to support a bottom surface of the first separator and transfer the first separator, a discharge roller configured to transfer the first separator that has passed through the transfer roller while supporting a top surface of the first separator, wherein a coating groove having the first width and a closed curve shape is formed in a circumferential surface of the discharge roller, and a coating member configured to inject an adhesive into a space between the discharge roller and the top surface of the first separator that has passed through the transfer roller. As the adhesive flows in the coating groove of the discharge roller, the adhesive layer having the first width is continuously applied on the top surface of the first separator.

Description

[0001] Cross-reference to related applications

[0002] This application claims priority to Korean Patent Application No. 10-2020-0105431, filed on August 21, 2020, and Korean Patent Application No. 10-2021-0107337, filed on August 13, 2021, the disclosures of which are incorporated herein by reference. Technical Field

[0003] This invention relates to an adhesive layer coating unit, an electrode assembly manufacturing apparatus including the adhesive layer coating unit, and an electrode assembly manufacturing method. More specifically, it relates to an adhesive layer coating unit that can apply an adhesive layer with uniform width and thickness to the surface of a diaphragm and alternately arrange electrodes and diaphragms coated with the adhesive layer to prevent electrode misalignment, an electrode assembly manufacturing apparatus including the adhesive layer coating unit, and an electrode assembly manufacturing method. Background Technology

[0004] Generally, a secondary battery refers to a rechargeable and dischargeable battery, which is different from a non-rechargeable primary battery. Such secondary batteries are widely used in high-tech electronics fields, such as telephones, portable computers, and portable cameras.

[0005] Secondary batteries are classified into can-type and pouch-type secondary batteries. In can-type secondary batteries, the electrode assembly is stored in a metal can, while in pouch-type secondary batteries, the electrode assembly is stored in a pouch. Furthermore, a pouch-type secondary battery includes an electrode assembly with electrode tabs, electrode leads coupled to the electrode tabs, and a battery casing that houses the electrode assembly with the front ends of the electrode leads pulled outwards. Additionally, the electrode assembly has a structure with alternating stacked electrodes and separators, and the battery casing includes a receiving portion for housing the electrode assembly and a sealing portion formed along the edge surface of the receiving portion.

[0006] Meanwhile, the method of manufacturing the electrode assembly includes: providing a first diaphragm; disposing an electrode on the top surface of the first diaphragm; disposing a second diaphragm on the top surface of the electrode; combining the first diaphragm, the electrode, and the second diaphragm; and cutting the first diaphragm and the second diaphragm located between the electrodes spaced apart from each other.

[0007] However, during the manufacturing process of the electrode assembly according to the prior art, the position of the electrode disposed between the first diaphragm and the second diaphragm fluctuates and deviates. That is, a misalignment failure occurs in the electrode. Summary of the Invention

[0008] Technical issues

[0009] One object of the present invention is to provide an adhesive layer coating unit, an electrode assembly manufacturing apparatus including the adhesive layer coating unit, and an electrode assembly manufacturing method, which can apply an adhesive layer having a uniform width and thickness to the surface of a diaphragm and alternately stack electrodes and diaphragms. Therefore, the electrodes can be bonded to the diaphragm during the manufacturing of the electrode assembly, thus preventing electrode wobbling and misalignment, that is, preventing electrode skew failure.

[0010] Technical solution

[0011] The present invention provides an adhesive layer coating unit configured to continuously apply an adhesive layer having a first width in the longitudinal direction of a first diaphragm. The adhesive layer coating unit includes: a conveying roller configured to support the bottom surface of the first diaphragm and convey the first diaphragm; an exit roller configured to convey the first diaphragm, having passed through the conveying roller, together with the conveying roller while supporting the top surface of the first diaphragm, wherein a coating groove having the first width and a closed-curve shape is formed in the circumferential surface of the exit roller; and a coating member configured to inject adhesive into the space between the exit roller and the top surface of the first diaphragm that has passed through the conveying roller, wherein as the adhesive flows in the coating groove of the exit roller, the adhesive layer having the first width is continuously applied to the top surface of the first diaphragm.

[0012] The coating tank may have a depth of 5 to 15 μm, and an adhesive layer with a thickness of 5 to 15 μm may be applied to the top surface of the first diaphragm.

[0013] The center point of the discharge roller may be located on a different vertical line from the center point of the conveyor roller, and the center point of the discharge roller may be located above the center point of the conveyor roller.

[0014] The first width may be less than the width of the first diaphragm.

[0015] The adhesive layer may be provided with acrylate or epoxy resin as a curable monomer.

[0016] The adhesive layer coating unit may further include a curing member that emits light toward the first diaphragm and cures the adhesive layer continuously applied to the first diaphragm to a set viscosity.

[0017] The set viscosity can be 50,000 to 100,000 cPs at 25°C.

[0018] The electrode assembly manufacturing apparatus of the present invention includes: a first diaphragm supply unit configured to supply a first diaphragm; an adhesive layer coating unit configured to continuously apply an adhesive layer having a first width in the longitudinal direction of the first diaphragm; an electrode supply unit configured to place an electrode on the adhesive layer applied to the first diaphragm; and a second diaphragm supply unit configured to place a second diaphragm on the top surface of the electrode.

[0019] The electrode assembly manufacturing apparatus may further include: a lamination unit configured to combine a stack of the first diaphragm, the electrode, and the second diaphragm that has been supplied by the second diaphragm supply unit; and a cutting unit configured to cut the first diaphragm and the second diaphragm between electrodes located in a stack spaced apart from each other.

[0020] The electrode assembly manufacturing method of the present invention includes: a first diaphragm supply process for supplying a first diaphragm; an adhesive layer coating process for continuously applying an adhesive layer having a first width in the longitudinal direction of the first diaphragm; an electrode supply process for disposing an electrode on the adhesive layer applied to the first diaphragm; and a second diaphragm supply process for disposing a second diaphragm on the top surface of the electrode disposed on the first diaphragm, wherein the adhesive layer coating process includes: a conveying process for conveying the first diaphragm while supporting the bottom surface of the first diaphragm using a conveying roller; a discharging process for conveying the first diaphragm that has passed through the conveying roller together with the conveying roller while supporting the top surface of the first diaphragm using a discharging roller, wherein a coating groove having the first width and a closed curve shape is formed in the circumferential surface of the discharging roller; and a solution casting process for injecting adhesive into the space between the discharging roller and the top surface of the first diaphragm that has passed through the conveying roller, wherein as the adhesive flows in the coating groove of the discharging roller, an adhesive layer having the first width is continuously applied to the top surface of the first diaphragm.

[0021] When the solution casting process is completed, the adhesive layer coating process may further include a curing process, which cures the adhesive layer applied to the first diaphragm to a set viscosity.

[0022] The coating tank may have a depth of 5 to 15 μm, and the adhesive layer with a thickness of 5 to 15 μm may be applied to the top surface of the first diaphragm.

[0023] The adhesive layer may be provided with acrylate or epoxy resin as a curable monomer.

[0024] In the curing process, light can be emitted onto the first diaphragm conveyed by the discharge roller, and the adhesive layer applied to the first diaphragm is cured to the set viscosity, wherein the set viscosity is 50,000 to 100,000 cPs at 25°C, such that the adhesion between the electrode and the first diaphragm is 20 to 40 gf.

[0025] When the second diaphragm supply process is completed, the electrode assembly manufacturing method may further include: a lamination process for stacking the first diaphragm, the electrode and the second diaphragm; and a cutting process for cutting the first diaphragm and the second diaphragm between the electrodes located in the stack spaced apart from each other.

[0026] Beneficial effects

[0027] The adhesive layer coating unit of the present invention includes a conveying roller, a discharge roller, a coating member, and a curing member, so that an adhesive layer having a first width can be conveniently applied to the surface of a first diaphragm. Therefore, work efficiency can be improved and the process can be simplified.

[0028] Furthermore, the adhesive layer coating unit of the present invention further includes a housing, thereby forming a receiving space filled with a certain amount of adhesive between the housing, the conveying roller, and the discharge roller. Therefore, the adhesive can be uniformly injected or applied onto the entire first diaphragm passing through the conveying roller and the discharge roller.

[0029] Furthermore, the curing component of the adhesive layer coating unit of the present invention uses a UV lamp to emit light. Therefore, the adhesive can cure simultaneously with application to the top surface of the first diaphragm.

[0030] Furthermore, the electrode assembly manufacturing apparatus of the present invention includes a first diaphragm supply unit, an adhesive layer coating unit, a curing unit, an electrode supply unit, and a second diaphragm supply unit. In this way, the adhesive layer is applied to the top surface of the first diaphragm, thereby preventing electrode wobbling and misalignment during electrode placement with the first diaphragm, that is, preventing electrode skew failure.

[0031] Furthermore, in the electrode assembly manufacturing apparatus of the present invention, the center point of the conveyor roller and the center point of the discharge roller are located on different vertical lines, and the center point of the discharge roller is located above the center point of the conveyor roller. That is, because the discharge roller is held at a higher position than the conveyor roller, it is possible to prevent the adhesive applied to the first diaphragm between the conveyor roller and the discharge roller from overflowing onto the discharge roller. Attached Figure Description

[0032] Figure 1 This is a perspective view illustrating an adhesive coating unit according to a first embodiment of the present invention.

[0033] Figure 2 This is a side cross-sectional view illustrating an adhesive coating unit according to a first embodiment of the present invention.

[0034] Figure 3 This is a planar cross-sectional view illustrating an adhesive coating unit according to a first embodiment of the present invention.

[0035] Figure 4 This is a schematic diagram illustrating a process diagram of an electrode assembly manufacturing apparatus according to a second embodiment of the present invention.

[0036] Figure 5 This is a plan view illustrating a stack manufactured by an electrode assembly manufacturing apparatus according to a second embodiment of the present invention.

[0037] Figure 6 This is a flowchart illustrating a method for manufacturing an electrode assembly according to a second embodiment of the present invention.

[0038] Figure 7 This is a view showing a preparation example manufactured using an electrode assembly manufacturing apparatus according to a second embodiment of the present invention.

[0039] Figure 8 This is a graph measuring the adhesive force of a preparation example manufactured using an electrode assembly manufacturing apparatus according to a second embodiment of the present invention. Detailed Implementation

[0040] In the following, embodiments of the invention will be described in detail with reference to the accompanying drawings to facilitate implementation by those skilled in the art. However, the invention can be implemented in various different forms and is not limited to the embodiments described herein. Furthermore, in the drawings, parts irrelevant to the description will be omitted for clarity, and similar elements will be indicated by similar reference numerals throughout the specification.

[0041] [Electrode assembly of the present invention]

[0042] refer to Figure 4 The electrode assembly of the present invention includes one or more electrode assemblies 10, each electrode assembly 10 having a structure in which a first diaphragm 11, an adhesive layer 12, an electrode 13 and a second diaphragm 14 are alternately arranged.

[0043] Please refer to this. Figure 4 The enlarged view shows an adhesive layer 12 with a first width disposed on the top surface of the first diaphragm and having a completely uniform thickness. Specifically, the first width α of the adhesive layer 12 is set to 3% to 7% of the total width β of the first diaphragm, preferably 5%.

[0044] In the electrode assembly with the above-described structure of the present invention, the adhesive layer 12 prevents the electrode 13 disposed on the top surface of the first separator 11 from shaking and deviating, that is, it prevents electrode misalignment failure. Furthermore, battery performance degradation can be prevented by optimizing the width of the adhesive layer.

[0045] Meanwhile, a first diaphragm coated with an adhesive layer is manufactured by an adhesive layer coating unit according to the first embodiment of the present invention.

[0046] [Adhesive layer coating unit according to a first embodiment of the present invention]

[0047] The adhesive layer coating unit according to a first embodiment of the present invention has a structure capable of continuously applying adhesive layers of the same width and thickness to the surface of a diaphragm using a novel method. Therefore, work efficiency can be improved and the process can be simplified.

[0048] In other words, such as Figures 1 to 3 As shown, the adhesive layer coating unit 120 according to the first embodiment of the present invention is used to continuously apply an adhesive layer 12 in the longitudinal direction of the first diaphragm 11. Specifically, the adhesive layer coating unit 120 can apply multiple adhesive layers 12 in the width direction of the first diaphragm 11, that is, the adhesive layer coating unit 120 has a structure for patterning and coating the surface of the first diaphragm with adhesive layers.

[0049] As an example, the adhesive layer coating unit 120 includes a transfer roller 121, an discharge roller 122, a coating member 123, and a curing member 130.

[0050] Conveyor rollers

[0051] The conveyor roller 121 supports the bottom surface of the first diaphragm 11 and moves the first diaphragm 11 from one side to the other during rotation (in Figure 1 (Observe from left to right when viewing from the center).

[0052] Discharge roller

[0053] The discharge roller 122, while supporting the top surface of the first diaphragm 11, conveys the first diaphragm 11, which has already passed through the transfer roller 121, together with the transfer roller 121. A coating groove 122a, having a first width and a closed curve shape, is formed on the circumferential surface of the discharge roller. Here, the first width α is smaller than the width β of the first diaphragm.

[0054] That is, the discharge roller 122 includes a coating trough 122a with a closed curve shape and a support surface 122b that supports the first diaphragm 11 while conveying the first diaphragm 11.

[0055] Coated components

[0056] The coating member 123 injects adhesive 12a into the gap between the discharge roller 122 and the top surface of the first diaphragm 11, which has already passed through the transfer roller 121. Thus, as the adhesive 12a flows in the coating trough 122a of the discharge roller 122, an adhesive layer 12 having a first width is continuously applied to the top surface of the first diaphragm 11.

[0057] Meanwhile, the coating component 123 includes: a storage tank for storing adhesive; and an injection nozzle for injecting the adhesive stored in the storage tank into the gap between the discharge roller 122 and the top surface of the first diaphragm 11.

[0058] In the adhesive layer coating unit 120 having the above-described structure according to the first embodiment of the present invention, when the first diaphragm 11 is conveyed by the conveying roller 121 and the discharge roller 122, the coating member 123 applies adhesive to the gap between the discharge roller 122 and the top surface of the first diaphragm 11 that has passed through the conveying roller 121. Therefore, since the adhesive 12a flows only in the coating trough 122a of the discharge roller 122, the adhesive layer 12 having a first width is continuously applied to the first diaphragm 11 in the longitudinal direction.

[0059] Here, the adhesive layer 12 has the same width and thickness as the coating tank 122a. Meanwhile, due to the support surface 122b of the discharge roller 122, no adhesive layer is formed on the remaining portion of the first diaphragm 11 other than the coating tank 122a.

[0060] Therefore, the adhesive layer coating unit 120 according to the first embodiment of the present invention can continuously apply the adhesive layer 12 in the longitudinal direction of the first diaphragm 11. This improves work efficiency and simplifies the process.

[0061] In particular, even without separate adjustment processing, the adhesive layer coating unit 120 according to the first embodiment of the present invention can continuously apply an adhesive layer with the same width and thickness on the surface of the diaphragm.

[0062] Meanwhile, the discharge roller 122 may further include at least one coating groove with a second width on its circumferential surface, so that the surface of the first diaphragm can be patterned and coated with two or more adhesive layers.

[0063] Specifically, the first width and the second width can be equal to or different from each other. That is, when the first width and the second width are equal to each other, the surface of the first diaphragm can be patterned and coated with an adhesive layer of the same width. When the first width and the second width are different from each other, the surface of the first diaphragm can be patterned and coated with an adhesive layer of different widths.

[0064] Meanwhile, the depth of the coating tank 122a is 5 to 15 μm, preferably 8 to 10 μm. Therefore, an adhesive layer 12 with a thickness of 5 to 15 μm, preferably 8 to 10 μm, can be applied to the top surface of the first diaphragm 11.

[0065] Here, when the depth of the coating tank 122a is 5 μm or less, the adhesive layer cannot flow smoothly in the coating tank 122a, and therefore defective adhesive layers 12 may be formed. In addition, when the depth of the coating tank 122a is 15 μm or more, the number of stacked electrodes will decrease due to the increased thickness of the stack, resulting in a deterioration in battery performance.

[0066] Therefore, the depth of the coating tank 122a is 5 μm to 15 μm. Thus, the adhesive layer 12 with a thickness of 5 to 15 μm can be stably applied to the top surface of the first separator 11, and the battery performance can be stably ensured.

[0067] At the same time, when Figure 2 When viewed from the ground, the discharge roller 122 is positioned above the conveyor roller 121. That is, when viewed relative to the ground, the center point a1 of the conveyor roller 121 and the center point a2 of the discharge roller 122 are on different vertical lines, and the center point a2 of the discharge roller 122 is positioned above the center point a1 of the conveyor roller 122. Therefore, it is possible to prevent the adhesive 12a applied to the first diaphragm 11 between the conveyor roller 121 and the discharge roller 122 from overflowing the discharge roller 122.

[0068] Meanwhile, the coating component 123 applies the adhesive 12a to the top surface of the first diaphragm 11 through a solution casting process, so that the adhesive 12a can be stably applied to the top surface of the first diaphragm 11.

[0069] Meanwhile, the area of ​​the adhesive layer 12 is set to not exceed 5% of the total area of ​​the first separator 11. That is, when the area of ​​the adhesive layer 12 is greater than 5% of the area of ​​the first separator 11, the battery performance decreases by 3% or more.

[0070] Meanwhile, the adhesive layer coating unit 120 further includes a housing 124. The conveyor roller 121 and the discharge roller 122 are mounted inside the housing 124, thereby terminating the two ends between the conveyor roller 121 and the discharge roller 122.

[0071] That is, the conveyor roller 121 and the discharge roller 122 are rotatably mounted in the housing 124, and the two inner walls of the housing 124 terminate the side portion between the conveyor roller 121 and the discharge roller 122. Therefore, the housing prevents the adhesive applied to the first diaphragm between the conveyor roller 121 and the discharge roller 122 from flowing downwards to the side portion of the conveyor roller 121 and the discharge roller 122.

[0072] Meanwhile, the adhesive layer coating unit according to the first embodiment of the present invention further includes a curing member 130, which cures the adhesive layer that has been applied to the first diaphragm to a set viscosity.

[0073] Curing components

[0074] The curing member 130 is disposed below the discharge roller 122 and irradiates light onto the first diaphragm 11 conveyed along the discharge roller 122, causing the adhesive layer 12 applied to the first diaphragm 11 to cure.

[0075] Here, the curing component 130 can be one of a mercury lamp, a metal halide lamp, or a UV LED to increase the curing strength of the adhesive layer 12 applied to the first diaphragm 11. Specifically, a UV LED is used. Here, when using a UV LED, 0.5 J / cm² is applied. 2 The intensity of the light source.

[0076] Simultaneously, the curing component 130 cures the adhesive layer, ensuring that the adhesive layer does not penetrate 30% or more, preferably 20% or more, of the thickness of the first diaphragm. Therefore, the coupling between the adhesive layer and the first diaphragm 11 can be enhanced, while minimizing the thickness deviation of the adhesive layer 12.

[0077] Meanwhile, the viscosity can be set to 50,000 to 100,000 cPs at 25°C, preferably 65,000 cPs. Here, when the viscosity is set to 50,000 cPs or less, all the adhesive is immersed in the porous membrane, and the adhesive may flow out from the opposite surface of the membrane. When the viscosity is set to 100,000 cPs or greater, the adhesive is difficult to mix, and due to poor flowability, the adhesive cannot be injected into the coating tank 122a. Therefore, the viscosity can be set to 50,000 to 100,000 cPs at 25°C, so that the adhesive layer can be stably applied to the top surface of the first membrane.

[0078] Meanwhile, when the viscosity is set to 50,000 to 100,000 cPs at 25°C, the adhesion force between the electrode and the first diaphragm is 20 to 40 gf.

[0079] Simultaneously, the adhesive layer contains a curable material. For example, the adhesive contains acrylate or epoxy resin as monomers. In particular, the acrylate or epoxy resin has high strength when cured by ultraviolet light.

[0080] In the following description of another embodiment of the invention, components having the same function as those in the foregoing embodiments are given the same reference numerals, and repeated descriptions of them will be omitted.

[0081] [Electrode assembly manufacturing apparatus according to a second embodiment of the present invention]

[0082] The electrode assembly manufacturing apparatus 100 according to the second embodiment of the present invention includes an adhesive layer coating unit 120 according to the first embodiment described above.

[0083] In other words, such as Figure 4 As shown, the electrode assembly manufacturing apparatus 100 according to the second embodiment of the present invention is used to manufacture a stack 10 in which a first diaphragm 11, an adhesive layer 12, an electrode 13 and a second diaphragm 14 are stacked in sequence, and includes a first diaphragm supply unit 110, an adhesive layer coating unit 120, a curing member 130, an electrode supply unit 140, a second diaphragm supply unit 150, a lamination unit 160 and a cutting unit 170.

[0084] First diaphragm supply unit

[0085] The first diaphragm supply unit 110 has a roller structure on which the first diaphragm 11 is wound, and the wound first diaphragm 11 is supplied to the adhesive layer coating unit 120 when the roller structure rotates.

[0086] Adhesive layer coating unit

[0087] The adhesive layer coating unit 120 is used to continuously apply an adhesive layer 12 having a first width in the longitudinal direction of the first diaphragm 11, and includes a transfer roller 121, a discharge roller 122, a coating member 123 and a curing member 130.

[0088] Meanwhile, the adhesive layer coating unit 120 has the same structure and function as the adhesive layer coating unit of the first embodiment, so its detailed description will be omitted.

[0089] Specifically, the adhesive layer coating unit 120 has a structure for patterning and coating the top surface of the first diaphragm 11 with the adhesive layer 12.

[0090] In other words, the adhesive layer coating unit 120 includes: a transfer roller 121 that supports the bottom surface of the first diaphragm 11 and transfers the first diaphragm 11 from one side to the other (in... Figure 1 (From left to right in the middle); discharge roller 122, supporting the top surface of the first diaphragm 11 that has passed through the transfer roller 121, conveying the first diaphragm 11 to the electrode supply unit 140, and having a coating groove 122a extending along the outer circumferential surface and having a closed curve shape; and coating member 123, applying adhesive 12a to the top surface of the first diaphragm 11 passing between the transfer roller 121 and the discharge roller 122. As the adhesive 12a flows in the coating groove 122a of the discharge roller 122, the top surface of the first diaphragm 11 is patterned and coated with an adhesive layer 12.

[0091] Electrode supply unit

[0092] The electrode supply unit 140 places the electrode 13 on the top surface of the first diaphragm 11 coated with an adhesive layer 12. Here, the electrode 13 is attached to the top surface of the first diaphragm 11 by the adhesive force of the adhesive layer 12, thus preventing electrode misalignment.

[0093] Second diaphragm supply unit

[0094] The second diaphragm supply unit 150 places the second diaphragm 14 on the top surface of the electrode 13, and the second diaphragm 14 is symmetrically arranged with the first diaphragm 11. Thus, the stacking 10 in which the first diaphragm 11, the adhesive layer 12, the electrode 13 and the second diaphragm 14 are stacked in sequence is completed.

[0095] lamination unit

[0096] The lamination unit 160 presses and combines the stack 10 that has been supplied by the second diaphragm supply unit 150.

[0097] Cutting unit

[0098] refer to Figure 5 The cutting unit 170 cuts the first diaphragm 11 and the second diaphragm 14 between the electrodes 13 located in the stack 10 that are spaced apart from each other.

[0099] Therefore, the electrode assembly manufacturing apparatus according to the second embodiment of the present invention can manufacture a stack 10 of a first diaphragm 11, an adhesive layer 12, an electrode 13, and a second diaphragm 14. In particular, the first diaphragm 11 and the electrode 13 are bonded together by the adhesive layer 12, thus preventing misalignment failure of the electrode 13. As a result, productivity can be improved and the defect rate can be reduced.

[0100] Hereinafter, a method for manufacturing an electrode assembly according to a second embodiment of the present invention will be described.

[0101] [Electrode assembly manufacturing method according to a second embodiment of the present invention]

[0102] like Figure 6 As shown, the electrode assembly manufacturing method according to the second embodiment of the present invention includes a first diaphragm supply process (S10), an adhesive layer coating process (S20), a curing process (S30), an electrode supply process (S40), a second diaphragm supply process (S50), a lamination process (S60), and a cutting process (S70).

[0103] First diaphragm supply process

[0104] The first diaphragm supply process (S10) supplies the first diaphragm 11 wound on the first diaphragm supply unit 110 to the adhesive layer coating unit.

[0105] Adhesive layer coating process

[0106] The adhesive layer coating process (S20) applies adhesive to the top surface of the first diaphragm 11 through the adhesive layer coating unit 120, thus coating the top surface with an adhesive layer 12. In particular, the adhesive layer coating process (S20) applies the adhesive layer 12 continuously in the longitudinal direction of the first diaphragm 11.

[0107] In other words, the adhesive layer coating process (S20) includes a conveying process, a discharge process, a solution casting process, and a curing process. Furthermore, the adhesive layer coating unit 120 includes a conveying roller 121, a discharge roller 122, a coating component 123, a housing 124, and a curing component 130.

[0108] In the conveying process, when the first diaphragm 11 is supplied through the first diaphragm supply process (S10), the conveying roller 121 conveys the first diaphragm 11 to the discharge roller 122 while supporting the bottom surface of the first diaphragm 11.

[0109] In the discharge process, the discharge roller 122 supports the top surface of the first diaphragm 11 while, together with the transfer roller 121, conveys the first diaphragm 11, which has passed through the transfer roller 121, to the electrode supply unit 140. At the same time, a coating groove 122a with a closed curve shape is formed in the circumferential surface of the discharge roller 122.

[0110] In the solution casting process, adhesive 12a is injected through coating member 123 into the gap between the discharge roller 122 and the top surface of the first diaphragm 11, which has already passed through the transfer roller 121. Therefore, because the adhesive 12a injected into the top surface of the first diaphragm 11 flows only in the coating trough 122a of the discharge roller 122, an adhesive layer 12 having the same shape and width as the coating trough can be applied to the top surface of the first diaphragm.

[0111] For example, when the coating tank is formed to have a depth of 5 to 15 μm, the adhesive layer applied to the first diaphragm 11 may have a thickness of 5 to 15 μm.

[0112] In the curing process, the adhesive layer 12 applied to the first diaphragm 11 can be cured to a set viscosity. That is, in the curing process, light (high-temperature light or heat) is emitted onto the first diaphragm 11 conveyed along the discharge roller 122 using a curing member 130. Therefore, the adhesive layer 12 applied to the first diaphragm can be cured to a set viscosity. Here, the curing strength of the curing member 130 can be adjusted so that the adhesive layer does not penetrate into 30% or more, preferably 20% or more, of the thickness of the first diaphragm 11.

[0113] Meanwhile, the suitable viscosity of the adhesive is 50,000 to 100,000 cPs at 25°C, so the adhesive can be cured to a thickness of 30% or more without penetrating into the first diaphragm 11. Here, the adhesive force between the electrode and the first diaphragm is 20 to 40 gf.

[0114] At the same time, the adhesive layer contains a curable material. For example, the adhesive layer contains acrylate or epoxy resin as monomers, which can improve the curing strength of the adhesive.

[0115] Additionally, the curing component 130 can be one of a mercury lamp, a metal halide lamp, or a UV LED to increase the curing strength of the adhesive layer 12 applied to the first diaphragm 11. Preferably, a UV LED is used.

[0116] Simultaneously, the solution casting and curing processes are carried out concurrently, allowing the adhesive to cure as it is applied to the first diaphragm. This simplifies the process and prevents the adhesive from adhering to the discharge roller.

[0117] Electrode supply process

[0118] In the electrode supply process (S40), the electrode 13 is disposed on the adhesive layer 12 applied to the first diaphragm 11. Therefore, because the electrode 13 is bonded to the first diaphragm 11 through the adhesive layer 12, the adhesion is enhanced. Thus, when the first diaphragm, on which the electrode is disposed, is conveyed, electrode wobbling and deviation can be prevented.

[0119] Second diaphragm supply process

[0120] In the second diaphragm supply process (S50), a second diaphragm 14 is disposed on the top surface of the electrode 12 disposed on the first diaphragm 11. Thus, a stacking 10 is completed in which the first diaphragm 11, the adhesive layer 12, the electrode 13, and the second diaphragm 14 are sequentially stacked. Here, the electrode 13 is held in place while being bonded to the first diaphragm 11 by the adhesive layer 12, thus preventing skewness failure of the electrode 13.

[0121] Lamination process

[0122] The lamination process (S60) rolls and bonds the stack 10 in which the first diaphragm 11, the adhesive layer 12, the electrode 13 and the second diaphragm 14 are stacked in sequence.

[0123] Cutting process

[0124] The cutting process (S70) cuts the first diaphragm 11 and the second diaphragm 14 between the electrodes 13 in the stack that are spaced apart from each other, thus creating a complete stack with specific dimensions.

[0125] [Experimental Example]

[0126] The adhesive force of electrodes provided in a complete product manufactured by the electrode assembly manufacturing method according to a second embodiment of the present invention is measured.

[0127] In other words, an adhesive layer containing an acrylate material as a curable monomer is applied to the top surface of the first diaphragm, thus the top surface is coated with the adhesive layer 12. The adhesive layer 12 is then cured to a set viscosity by a curing member. Next, an electrode is placed on the adhesive layer 12 applied to the first diaphragm, and a second diaphragm is placed on the top surface of the electrode. Thus, a complete stack is manufactured.

[0128] Here, the adhesive layer has a thickness of 7 to 8 μm and a viscosity of 65,000 cPs. Additionally, the component is cured using a UV LED at a rate of 0.5 J / cm². 2 The intensity of the UV LED. Here, it can be confirmed that the adhesive layer has not penetrated 20% or more of the thickness of the first diaphragm.

[0129] Experimental results

[0130] like Figure 7 As shown, adhesive force is measured at three points on the complete stack. That is, the adhesive force is measured in the upper region A and lower region C of the complete stack without adhesive layer 12, and in the central region B of the complete stack with adhesive layer 12.

[0131] As a result, Figure 8 As shown, in region B, which has an adhesive layer, the coupling force between the electrode and the first diaphragm was measured to be 18 to 25 gf. Furthermore, in regions A and C, which do not have an adhesive layer, the coupling force between the electrode and the first diaphragm was measured to be 6 to 8 gf.

[0132] Therefore, it can be confirmed that the adhesive force of region B is 2.5 times that of regions A and C, thus significantly preventing the electrodes set on the first diaphragm from deviating.

[0133] The scope of this invention is defined by the appended claims rather than the detailed description, and various embodiments derived from the meaning and scope of the claims and their equivalents are also possible.

[0134] [Explanation of reference numerals in the attached figures]

[0135] a1: Center point of the conveyor roller

[0136] a2: Center point of the discharge roller

[0137] 11: First diaphragm

[0138] 12: Adhesive layer

[0139] 12a: Adhesive

[0140] 13: Electrode

[0141] 14: Second diaphragm

[0142] 100: Electrode assembly manufacturing equipment

[0143] 110: First diaphragm supply unit

[0144] 120: Adhesive layer coating unit

[0145] 121: Conveyor Roller

[0146] 122: Discharge roller

[0147] 122a: Coating tank

[0148] 123: Coated components

[0149] 124: Shell

[0150] 130: Curing component

[0151] 140: Electrode supply unit

[0152] 150: Second diaphragm supply unit

[0153] 160: Laminated unit

[0154] 170: Cutting unit

Claims

1. An adhesive layer coating unit configured to continuously apply an adhesive layer having a first width in a longitudinal direction of a first separator, the adhesive layer coating unit comprising: a transfer roller configured to support a bottom surface of the first separator and transfer the first separator; a discharge roller configured to transfer the first separator that has passed through the transfer roller while supporting a top surface of the first separator, wherein a coating groove having the first width and a closed curve shape in a direction parallel to a rotation axis of the discharge roller is formed in a circumferential surface of the discharge roller; and a coating member configured to inject an adhesive into a space between the discharge roller and a top surface of the first separator that has passed through the transfer roller, wherein a continuous line of the adhesive layer having the first width is continuously applied on the top surface of the first separator as the adhesive flows in the coating groove of the discharge roller. 2.The adhesive layer coating unit of claim 1, wherein a depth of the coating groove is 5 to 15 µm, and the adhesive layer having a thickness of 5 to 15 µm is applied on the top surface of the first separator. 3.The adhesive layer coating unit of claim 2, wherein a center point of the discharge roller and a center point of the transfer roller are located on different vertical lines, and the center point of the discharge roller is located above the center point of the transfer roller. 4.The adhesive layer coating unit of claim 1, wherein the first width is smaller than a width of the first separator. 5.The adhesive layer coating unit of claim 1, wherein the adhesive layer is provided with an acrylate or an epoxy resin as a curable monomer. 6.The adhesive layer coating unit of claim 1, further comprising a curing member that emits light to the first separator and cures the adhesive layer continuously applied on the first separator to a set viscosity. 7.The adhesive layer coating unit of claim 6, wherein the set viscosity is 50,000 to 100,000 cPs at 25 °C. 8.An electrode assembly manufacturing apparatus comprising: a first separator supply unit configured to supply a first separator; the adhesive layer coating unit of claim 1 that continuously applies an adhesive layer having a first width in a longitudinal direction of the first separator; an electrode supply unit configured to dispose an electrode on the adhesive layer applied to the first separator; and a second separator supply unit configured to dispose a second separator on a top surface of the electrode. 9.The electrode assembly manufacturing apparatus of claim 8, further comprising: a lamination unit configured to combine a stack of the first separator, the electrode, and the second separator that have passed through the second separator supply unit; and a cutting unit configured to cut the first separator and the second separator between the electrodes located in the stack spaced apart from each other. 10.An electrode assembly manufacturing method comprising: a first separator supply process for supplying a first separator; ​ ​ ​ an adhesive layer coating process for continuously applying an adhesive layer having a first width in a longitudinal direction of the first separator; an electrode supply process for disposing an electrode on the adhesive layer applied to the first separator; and a second separator supply process for disposing a second separator on a top surface of the electrode disposed on the first separator, wherein the adhesive layer coating process comprises: a conveying process for conveying the first separator while supporting a bottom surface of the first separator, using a conveying roller, an expelling process for conveying the first separator, which has passed through the conveying roller, while supporting a top surface of the first separator together with the conveying roller, using an expelling roller, wherein a coating groove having a first width in a direction parallel to an axis of rotation of the expelling roller and a closed curve shape is formed in a circumferential surface of the expelling roller, and a solution casting process for injecting an adhesive into a space between the expelling roller and the top surface of the first separator, which has passed through the conveying roller, wherein a continuous line of the adhesive layer having the first width is continuously applied on the top surface of the first separator as the adhesive flows in the coating groove of the expelling roller. When the solution casting process is completed, the adhesive layer coating process further comprises a curing process for curing the adhesive layer applied on the first separator to a set viscosity.

11. The electrode assembly production method according to claim 10, wherein 12.The electrode assembly manufacturing method of claim 10, wherein a depth of the coating groove is 5 to 15 µm, and the adhesive layer having a thickness of 5 to 15 µm is applied on the top surface of the first separator. 13.The electrode assembly manufacturing method of claim 11, wherein the adhesive layer is provided with an acrylate or an epoxy resin as a curable monomer. 14.The electrode assembly manufacturing method of claim 11, wherein in the curing process, light is emitted to the first separator conveyed by the expelling roller, and the adhesive layer applied on the first separator is cured to the set viscosity, wherein the set viscosity is 50,000 to 100,000 cPs at 25°C, such that an adhesive force between the electrode and the first separator is 20 to 40 gf. 15.The electrode assembly manufacturing method of claim 10, when the second separator supply process is completed, the electrode assembly manufacturing method further comprises: a lamination process for bonding a stack of the first separator, the electrode, and the second separator; and a cutting process for cutting the first separator and the second separator between electrodes located in the stack spaced apart from each other. ​ ​

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