Electrode assembly, manufacturing apparatus therefor, and manufacturing method therefor

Abstract

An electrode assembly manufacturing apparatus according to an embodiment of the present invention includes an electrode supplying unit that provides an electrode sheet on which a plurality of electrodes are formed; a separation membrane supplying unit that provides a separation membrane sheet that is folded when the electrodes are installed to cover the electrodes and be laminated with the electrodes; a table on which the electrodes are installed so as to have the separation membrane sheet folded between the electrodes to form the electrode assembly; a separation membrane guide that guides the folding direction of the separation membrane sheet; and a pair of upper coaters that apply adhesive to at least a portion of an upper portion of the electrodes installed on the table, wherein the separation membrane guide and the pair of upper coaters reciprocate linearly left and right based on the table, and the table is fixed.

Description

[Technical Field]

[0001] [CROSS-REFERENCE TO RELATED APPLICATIONS] This application claims the benefit of priority based on Korean Patent Application No. 10-2021-0124051, filed September 16, 2021, and Korean Patent Application No. 10-2022-0114323, filed September 8, 2022, and all contents disclosed in the documents of said Korean patent applications are incorporated herein by reference.

[0002] The present invention relates to an electrode assembly, a manufacturing apparatus therefor, and a manufacturing method therefor, and more particularly to a battery cell in which electrodes and separator sheets are stacked in a Z-folded manner, and an electrode assembly in which the electrodes can be prevented from coming off from their fixed positions, a manufacturing apparatus therefor, and a manufacturing method therefor. [Background technology]

[0003] Generally, types of secondary batteries include nickel-cadmium batteries, nickel-metal hydride batteries, lithium-ion batteries, lithium-ion polymer batteries, etc. These secondary batteries are used not only in small products such as digital cameras, DVD players, MP3 players, mobile phones, PDAs, portable game devices, power tools, and e-bikes, but also in large products that require high output, such as electric vehicles and hybrid vehicles, as well as in power storage devices and backup power storage devices that store surplus generated power and renewable energy.

[0004] To manufacture such a secondary battery, first, an electrode active material slurry is applied to a positive electrode current collector and a negative electrode current collector to form a positive electrode and a negative electrode, which are then laminated on both sides of a separator to form an electrode assembly of a predetermined shape, and then the electrode assembly is placed in a battery case, an electrolyte is injected, and the battery case is sealed.

[0005] Electrode assemblies are classified into various types. Examples include the simple stack type, in which positive electrodes, separators, and negative electrodes are simply stacked in a cross pattern without fabricating unit cells; the lamination and stack type (L&S), in which unit cells are fabricated using positive electrodes, separators, and negative electrodes and then stacked; the stack and folding type (S&F), in which multiple unit cells are attached at a distance to one side of a long separator sheet and then repeatedly folded in the same direction from one end; and the Z-folding type, in which multiple electrodes or unit cells are alternately attached to one side and the other side of a long separator sheet and then repeatedly folded in the opposite direction from one end. Of these, the Z-folding type has become increasingly popular in recent years due to its high degree of alignment and electrolyte impregnation.

[0006] However, in conventional Z-folded fuel cells, since a separate lamination process is not performed after stacking the electrodes and separator sheet, the electrodes and separator sheet are not adhered to each other, resulting in the problem of the electrodes coming off from their designated positions. To solve this problem, a separate lamination process is performed after stacking the electrodes and separator sheet, but since the overall thickness of the laminate containing the electrodes and separator sheet is increased, heat is not transferred to the interior of the laminate, resulting in a decrease in adhesive strength. Furthermore, to perform this separate lamination process, the electrodes come off from their designated positions during the process of transporting the laminate. This problem is exacerbated when the adhesive strength of the separator sheet itself is low due to the material of the separator sheet.

[0007] Therefore, there is a need to develop a battery cell assembly including a Z-folded electrode assembly that improves battery cell performance while preventing the electrodes from falling out of place, an apparatus for manufacturing the same, and a method for manufacturing the same. Summary of the Invention [Problem to be solved by the invention]

[0008] An object of the present invention is to provide an electrode assembly in which electrodes and separator sheets are stacked in a Z-folded manner, in which the electrodes can be prevented from coming off from their fixed positions, a manufacturing apparatus for the electrode assembly, and a manufacturing method for the electrode assembly.

[0009] The problems to be solved by the present invention are not limited to those described above, and problems not mentioned will be clearly understood by a person having ordinary skill in the art to which the present invention pertains from this specification and the accompanying drawings. [Means for solving the problem]

[0010] An electrode assembly manufacturing apparatus according to one embodiment of the present invention includes an electrode supplying unit that provides an electrode sheet on which a plurality of electrodes are formed; a separation membrane supplying unit that provides a separator sheet that is folded when the electrodes are installed to cover the electrodes and be laminated with the electrodes; a table that installs the electrodes on top of the electrode sheet so that the separator sheet is folded between the electrodes to form the electrode assembly; a separation membrane guide that guides the folding direction of the separation membrane sheet; and a pair of upper applicators that apply adhesive to at least a portion of the upper part of the electrodes installed on the table, wherein the separation membrane guide and the pair of upper applicators move linearly back and forth left and right based on the table, and the table is fixed.

[0011] The electrode supply unit may include a first electrode supply unit provided with a first electrode sheet on which a plurality of first electrodes are formed; and a second electrode supply unit provided with a second electrode sheet on which a plurality of second electrodes are formed.

[0012] The pair of upper applicators may include a first upper nozzle and a second upper nozzle, and the first upper nozzle may apply the adhesive to an upper portion of the first electrode, and the second upper nozzle may apply the adhesive to an upper portion of the second electrode.

[0013] The first upper nozzle and the second upper nozzle may be disposed on either side of the separation membrane guide.

[0014] The first electrode may be disposed on a first region of the separator sheet, and the second electrode may be disposed on a second region of the separator sheet.

[0015] When the first electrode is placed on a first region of the separation membrane sheet, the first upper nozzle can move linearly on the first electrode, and when the second electrode is placed on a second region of the separation membrane sheet, the second upper nozzle can move linearly on the second electrode.

[0016] When the first upper nozzle applies the adhesive to at least a portion of the upper surface of the first electrode, the separation membrane guide can move linearly in a direction in which the separation membrane sheet covers the first electrode, and when the second upper nozzle applies the adhesive to at least a portion of the upper surface of the second electrode, the separation membrane guide can move linearly in a direction in which the separation membrane sheet covers the second electrode.

[0017] The apparatus may include a bottom applicator that applies the adhesive to a bottom of the first electrode and a bottom of the second electrode, respectively.

[0018] The substrate may further include a first header for adsorbing the first electrode and placing it in the first region; and a second header for adsorbing the second electrode and placing it in the second region.

[0019] When the first electrode is adsorbed to the first header, the lower coater can apply the adhesive to a lower portion of the first electrode, and when the second electrode is adsorbed to the second header, the lower coater can apply the adhesive to a lower portion of the second electrode.

[0020] The apparatus may further include a first transport device that transports the first electrode toward the table; and a second transport device that transports the second electrode toward the table.

[0021] The first transfer device includes a first groove that is open toward the first electrode, and the lower coater applies the adhesive to the lower part of the first electrode through the first groove, and the second transfer device includes a second groove that is open toward the second electrode, and the lower coater applies the adhesive to the lower part of the second electrode through the second groove.

[0022] A battery cell manufacturing method according to another embodiment of the present invention includes the steps of: cutting a first electrode sheet unwound from a first electrode supply unit to form a plurality of first electrodes; placing a separator sheet unwound from a separator supply unit on a table along a separator guide; applying adhesive to a lower portion of the first electrode with a lower coater; placing the first electrode in a first region of the separator sheet; applying adhesive to an upper portion of the first electrode with a first upper nozzle; and folding the separator sheet in a folding direction guided by the separator guide so that a second region of the separator sheet covers the first electrode.

[0023] After covering the tops of the first electrodes, the method may further include cutting the second electrode sheet unwound from a second electrode supply unit to form a plurality of second electrodes; applying adhesive to the bottoms of the second electrodes with a lower coater; installing the second electrodes in the second regions of the separator sheet; applying adhesive to the tops of the second electrodes with a second upper nozzle; and folding the separator sheet in a folding direction guided by a separator guide so that the first regions of the separator sheet cover the second electrodes.

[0024] The table is fixed, and the separation membrane guide, the first upper nozzle, and the second upper nozzle can move linearly back and forth based on the table.

[0025] In another embodiment of the present invention, there is provided an electrode assembly in which electrodes and separator sheets are alternately stacked, the electrodes including a first electrode and a second electrode, the separator sheet having a zigzag shape formed by being folded at least twice, the separator sheet being folded with the first electrode placed on a first region of the separator sheet and the second region of the separator sheet covering the first electrode, the separator sheet being folded with the second electrode placed on the second region of the separator sheet and the first region of the separator sheet covering the second electrode, and an adhesive layer being formed between the electrodes and the separator sheet.

[0026] The adhesive layer may include a first adhesive layer and a second adhesive layer, the first adhesive layer being located between the lower part of the electrode and the separator sheet, and the second adhesive layer being located between the upper part of the electrode and the separator sheet.

[0027] The first adhesive layer and the second adhesive layer may each be formed by applying an adhesive in the form of a plurality of dots.

[0028] A battery cell according to another embodiment of the present invention is a battery cell including the electrode assembly described above, and further includes a battery case that accommodates the electrode assembly together with an electrolyte, and the adhesive layer dissolves in the electrolyte. [Effects of the Invention]

[0029] According to the embodiments, the present invention provides an electrode assembly in which electrodes and separator sheets are stacked in a Z-folded manner and adhesive is pre-applied to the upper and lower parts of the electrodes, a manufacturing apparatus therefor, and a manufacturing method therefor, which can prevent the electrodes from coming off from their designated positions.

[0030] The effects of the present invention are not limited to the effects described above, and effects not mentioned will be clearly understood by those having ordinary skill in the art to which the present invention pertains from this specification and the accompanying drawings. [Brief explanation of the drawings]

[0031] [Figure 1] 1 is a flowchart of a method for manufacturing an electrode assembly according to an embodiment of the present invention. [Figure 2] 3 is a schematic view illustrating a state in which a first electrode is installed in a first region of a separator sheet in an electrode assembly manufacturing apparatus according to an embodiment of the present invention. [Figure 3] 4 is a schematic view showing a state in which an adhesive is applied to a lower part of a first electrode in an electrode assembly manufacturing apparatus according to an embodiment of the present invention. [Figure 4] 10 is a schematic view showing a state in which an adhesive is applied to a lower part of a first electrode in an electrode assembly manufacturing apparatus according to another embodiment of the present invention. [Figure 5] 1 is a schematic view illustrating a state in which a first upper nozzle applies adhesive to an upper portion of a first electrode while moving linearly in an electrode assembly manufacturing apparatus according to an embodiment of the present invention. [Figure 6] 10 is a schematic view illustrating a state in which a separator guide moves linearly and a second electrode is installed on a second region of a separator sheet in an electrode assembly manufacturing apparatus according to an embodiment of the present invention. [Figure 7] 10 is a schematic view illustrating a state in which a second upper nozzle applies adhesive to an upper portion of a second electrode while moving linearly in an electrode assembly manufacturing apparatus according to an embodiment of the present invention. [Figure 8] 1 is a cross-sectional view of an electrode assembly according to an embodiment of the present invention. [Figure 9] FIG. 2 is an exploded perspective view of a battery cell according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0032] The present invention can be embodied in various different forms and is not limited to the embodiments described herein.

[0033] In order to clearly explain the present invention, parts that are not relevant to the description will be omitted, and the same reference numerals will be used throughout the specification to refer to the same or similar components.

[0034] In addition, the size and thickness of each component shown in the drawings are arbitrarily shown for the convenience of explanation, and the present invention is not necessarily limited to those shown in the drawings. In the drawings, thicknesses are exaggerated to clearly show multiple layers and regions. In the drawings, thicknesses of some layers and regions are exaggerated for the convenience of explanation.

[0035] Furthermore, throughout the specification, when a part "comprises" a certain element, this does not mean that it excludes other elements, but that it may further include other elements, unless otherwise specified.

[0036] Also, throughout the specification, "in a plane" means when the part is viewed from above, and "in cross section" means when the part is cut vertically and viewed from the side.

[0037] A method for manufacturing a battery assembly according to an embodiment of the present invention will now be described.

[0038] 1 is a flowchart of a method for manufacturing an electrode assembly according to an embodiment of the present invention, and FIG. 2 is a schematic view showing a state in which a first electrode is installed in a first region of a separator sheet in an apparatus for manufacturing an electrode assembly according to an embodiment of the present invention.

[0039] According to an embodiment of the present invention, an electrode assembly manufacturing apparatus includes an electrode supplying unit that provides an electrode sheet on which a plurality of electrodes are formed; a separation membrane supplying unit that provides a separator sheet that is folded when the electrodes are installed to cover the electrodes and be laminated with the electrodes; a table that installs the electrodes on its upper surface so that the separator sheet is folded between the electrodes to form the electrode assembly; a separation membrane guide that guides the folding direction of the separator membrane sheet; and a pair of upper coaters that apply adhesive to at least a portion of an upper portion of the electrodes installed on the table, wherein the separation membrane guide and the pair of upper coaters reciprocate linearly left and right based on the table, and the table is fixed.

[0040] 1 and 2, a method for manufacturing an electrode assembly according to one embodiment of the present invention includes the steps of cutting electrode sheets 1111 and 1121 to form an electrode 11 (S101); placing a separator sheet 122 on a table 16 (S102); applying adhesive to the bottom of the electrode 11 (S103); placing the electrode 11 on the separator sheet 122 (S104); applying adhesive to the top of the electrode 11 (S104); and folding the separator sheet 122 to cover the electrode 11 (S105).

[0041] Therefore, in the electrode assembly manufacturing method according to this embodiment, when the electrode 11 and the separator sheet 122 are stacked in a Z-folding manner, adhesive is applied to the top and bottom of the electrode 11, preventing the electrode 11 from coming off from its designated position.

[0042] Each step shown in the flowchart of FIG. 1 will now be described in detail with reference to FIGS.

[0043] An electrode assembly manufacturing apparatus 1 according to one embodiment of the present invention includes electrode reels 111, 112 from which electrode sheets on which multiple electrodes 11 are formed are unwound; a separation membrane reel 121 from which a separator membrane sheet 122 is unwound, which is folded after the electrode 11 is installed to cover the electrode 11 and be laminated with the electrode 11; a table 16 on which the electrode 11 and the separator membrane sheet 122 are installed; a separation membrane guide 125 that guides the folding direction of the separator membrane sheet 122; and a pair of upper nozzles 17 that apply adhesive to at least a portion of the upper part of the electrode 11 installed on the table 16. The electrode reels 111, 112 are an example of the electrode supply unit described above, and the separation membrane reel 121 is an example of the separation membrane supply unit described above. The pair of upper nozzles 17 are an example of the upper coater described above.

[0044] The electrode reels 111, 112 may include a first electrode reel 111 from which a first electrode sheet 1111 on which a plurality of first electrodes 1112 are formed is unwound; and a second electrode reel 112 from which a second electrode sheet 1121 on which a plurality of second electrodes 1122 are formed is unwound.

[0045] The electrode reels 111, 112 are reels around which the electrode sheets 1111, 1121 are wound, and the electrode sheets 1111, 1121 are unwound from the electrode reels 111, 112. Then, the electrode sheets 1111, 1121 are cut to form the electrodes 11. More specifically, according to this embodiment, the first electrode reel 111 is a reel around which the first electrode sheet 1111 is wound, and the first electrode sheet 1111 is unwound from the second electrode reel 111. Furthermore, the second electrode reel 112 is a reel around which the second electrode sheet 1121 is wound, and the second electrode sheet 1121 is unwound from the second electrode reel 112.

[0046] Here, the electrode sheets 1111 and 1121 can be manufactured by applying a slurry of an electrode active material, a conductive material, and a binder onto an electrode current collector, drying the slurry, and pressing it. However, the manufacturing method of the electrode sheets 1111 and 1121 is not limited thereto, and any method for manufacturing the electrode sheets 1111 and 1121 generally used in the relevant technical field is included in this embodiment.

[0047] More specifically, the first electrode sheet 1111 and the second electrode sheet 1121 may contain electrode active materials having different polarities. That is, the first electrode 1112 and the second electrode 1122 are electrodes 11 having different polarities. For example, if the first electrode 1112 is a positive electrode, the second electrode 1122 is a negative electrode. For another example, if the first electrode 1112 is a negative electrode, the second electrode 1122 is a positive electrode.

[0048] The separator reel 121 is a reel on which the separator sheet 122 is wound, and the separator sheet 122 is unwound from the separator reel 121. The separator sheet 122 is then stacked on the electrode 11 formed by cutting the electrode sheets 1111 and 1121. Here, the electrode 11 and the separator sheet 122 are stacked in a Z-folded manner. More specifically, in this embodiment, when a first electrode 1112 is installed on the separator sheet 122, one side is folded to cover the first electrode 1112, and when a second electrode 1122 is installed, the other side is folded to cover the second electrode 1122. The separator sheet 122 may be zigzag-shaped.

[0049] The electrodes 11 and the separation membrane sheets 122 can be placed and stacked on the upper surface of the table 16. More preferably, the upper surface of the table 16 is formed to be substantially flat, so that the electrodes 11 and the separation membrane sheets 122 can be stably stacked.

[0050] The table 16 may be disposed between the first electrode reel 111 and the second electrode reel 112. More specifically, the table 16 may be fixed between the first electrode reel 111 and the second electrode reel 112.

[0051] As a result, the electrodes 11 and the separator sheets 122 are stacked on the table 16 while the table 16 is fixed, and the degree of alignment of the electrodes 11 and the separator sheets 122 can be further improved.

[0052] The electrode assembly manufacturing apparatus 1 according to this embodiment may further include a first transfer device 141 that transfers the first electrode 1112 toward the table 16, and a second transfer device 142 that transfers the second electrode 1122 toward the table 16. Here, the first transfer device 141 may transfer the first electrode 1112 formed by cutting the first electrode sheet 1111 unwound from the first electrode reel 111 toward the table 16. In addition, the second transfer device 142 may transfer the second electrode 1122 formed by cutting the second electrode sheet 1121 unwound from the second electrode reel 112 toward the table 16.

[0053] As a result, in this embodiment, the first electrode 1112 and the second electrode 1122 can be transported on both sides of the table 16 via the first transport device 141 and the second transport device 142, respectively, making it easy to alternately stack the first electrode 1112 and the second electrode 1122 on the separation membrane sheet 122.

[0054] The electrode assembly manufacturing apparatus 1 according to this embodiment may include headers 151 and 152 that adsorb the electrode 11 and install it on the separator sheet 122. More specifically, the headers 151 and 152 may further include a first header 151 that adsorbs the first electrode 1112 and installs it on the separator sheet 122, and a second header 152 that adsorbs the second electrode 1122 and installs it on the separator sheet 122. Here, the first header 151 and the second header 152 can each move linearly back and forth toward the table 16.

[0055] More specifically, the first header 151 can adsorb the first electrode 1112 transferred from the first transfer device 141 toward the table 16, and the second header 152 can adsorb the second electrode 1122 transferred from the second transfer device 142 toward the table 16. In addition, the first header 151 and the second header 152 can move linearly toward the table 16.

[0056] As a result, in this embodiment, the first header 151 and the second header 152 can move the electrode 11 above the table 16, and the electrode 11 can be stably installed on the separation membrane sheet 122.

[0057] In addition, the headers 151 and 152 can measure the presence or absence of misalignment of the first electrode 1112 or the second electrode 1122 for each first electrode 1112 or second electrode 1122, correct the position as necessary, and accurately install the headers 151 and 152 at the desired position on the separator membrane sheet 122 placed on the table 16. As a result, in this embodiment, the degree of alignment between the electrodes 11 and the separator membrane sheet 122 stacked and aligned on the table 16 can be further improved.

[0058] 2, in the electrode assembly manufacturing apparatus 1 according to this embodiment, the electrode 11 may be installed on the separator sheet 122 with an adhesive applied to at least a portion of the lower surface of the electrode 11. More specifically, in this embodiment, the adhesive may be applied to at least a portion of the lower surface of the electrode 11 when the electrode 11 is positioned on the transfer devices 141 and 142, or the adhesive may be applied to at least a portion of the lower surface of the electrode 11 when the electrode 11 is attached to the headers 151 and 152.

[0059] Fig. 3 is a schematic view showing a state in which an adhesive is applied to a lower portion of a first electrode in an electrode assembly manufacturing apparatus according to one embodiment of the present invention, and Fig. 4 is a schematic view showing a state in which an adhesive is applied to a lower portion of a first electrode in an electrode assembly manufacturing apparatus according to another embodiment of the present invention.

[0060] 3 and 4, the electrode assembly manufacturing apparatus 1 according to this embodiment may include a lower nozzle 173 that applies adhesive to at least a portion of the lower surface of the first electrode 1112. More specifically, the lower nozzle 173 may apply adhesive to at least a portion of the lower surface of the first electrode 1112. As a result, a first adhesive layer 1710 may be formed on the lower surface of the first electrode 1112. Here, the lower nozzle 173 is an example of a lower coater.

[0061] For example, referring to FIG. 3, when the first electrode 1112 is attached to the first header 151, the lower nozzle 173 may apply adhesive to at least a portion of the lower surface of the first electrode.

[0062] 4, the first transfer device 141a includes a first groove 141a' that opens toward the first electrode 1112, and the lower nozzle 173 can apply adhesive to at least a portion of the lower surface of the first electrode 1112 through the first groove 141a'. Here, the first transfer device 141a may be formed with at least one first groove 141a', and the plurality of first grooves 141a' may be spaced apart from one another. Furthermore, as shown in FIG. 4, the first groove 141a' may extend along the width direction of the first electrode 1112, but is not limited thereto and may extend in various directions.

[0063] However, for the sake of convenience, the first electrode 1112 is used as an example for the explanation, and the second electrode 1122 can be similarly explained as the second header 152 or the second transport device 142.

[0064] As a result, the electrode assembly manufacturing apparatus 1 according to this embodiment has the advantage that adhesive can be applied to at least a portion of the lower surface of the electrode 11 during the process of transporting the electrode 11, thereby improving the convenience and speed of the process.

[0065] Here, the adhesive is preferably applied uniformly to the lower surface of the electrode 11. However, if the adhesive is applied to the entire surface of the lower surface of the electrode 11, the amount of adhesive applied may be excessive. In this case, the adhesive may flow to the outside of the separator sheet 122 and contaminate other parts, which may hinder smooth power production when a secondary battery is manufactured.

[0066] Therefore, in this embodiment, the adhesive is preferably applied in a spot coating manner or a line coating manner to the lower part of the electrode 11. That is, the first adhesive layer 1710 is preferably formed in a spot pattern or a line pattern.

[0067] On the other hand, if the amount of adhesive applied is too small, the electrode 11 may not be fixed to the separator sheet 122 and may come off from its fixed position as the cell moves. Therefore, it is preferable that the spacing between the areas where the adhesive is applied is not too large.

[0068] In addition, the adhesive may be applied to the surface of the electrode 11 in a minimum amount sufficient to ensure adhesion between the electrode 11 and the separator sheet 122. In contrast, if the adhesive is applied directly to the separator sheet 122, the separator sheet 122 may absorb some of the adhesive, posing a problem that a larger amount of adhesive must be applied to ensure adhesion between the electrode 11 and the separator sheet 122.

[0069] Meanwhile, the adhesive may be dissolved in the electrolyte. More specifically, when first adhesive layer 1710 formed under electrode 11 is immersed in the electrolyte, the adhesive contained in first adhesive layer 1710 may be dissolved in the electrolyte. Here, "the adhesive dissolves" may mean that the adhesive dissolves in the electrolyte. That is, this means that the area of ​​first adhesive layer 1710 formed under electrode 11 is reduced, or that first adhesive layer 1710 is completely removed, so that no first adhesive layer 1710 remains under electrode 11.

[0070] For example, the adhesive may be an acrylate adhesive. In this embodiment, the adhesive is applied to the lower part of the electrode 11, so that the adhesive can dissolve in the electrolyte contained in the final battery cell.

[0071] Therefore, in this embodiment, the first adhesive layer 1710 fixes the electrode 11 to the separator sheet 122 during the manufacturing process, preventing it from coming off from its fixed position. In addition, the first adhesive layer 1710 dissolves in the electrolyte contained in the final battery cell, and does not interfere with the movement of lithium ions between the electrode and the separator, thereby further improving the performance of the battery cell.

[0072] FIG. 5 is a schematic view showing a state in which a first upper nozzle applies adhesive to an upper portion of a first electrode while moving linearly in an electrode assembly manufacturing apparatus according to an embodiment of the present invention.

[0073] 5, the pair of upper nozzles 17 applies adhesive to at least a portion of the upper surface of the electrode 11. More specifically, the pair of upper nozzles 17 includes a first upper nozzle 171 that applies adhesive to at least a portion of the upper surface of the first electrode 1112 and a second upper nozzle 172 that applies adhesive to at least a portion of the upper surface of the second electrode 1122.

[0074] The first upper nozzle 171 and the second upper nozzle 172 may be disposed on either side of the separation membrane sheet 122. That is, the first upper nozzle 171 can apply adhesive to at least a portion of the upper surface of the first electrode 1112 before the upper surface of the first electrode 1112 is covered by the separation membrane sheet 122, thereby forming the second adhesive layer 1750. The second upper nozzle 172 can apply adhesive to at least a portion of the upper surface of the second electrode 1122 before the upper surface of the second electrode 1122 is covered by the separation membrane sheet 122, as will be described later with reference to FIG. 7 .

[0075] In addition, the pair of upper nozzles 17 can move linearly back and forth from left to right based on the table 16. That is, the pair of upper nozzles 17 can apply adhesive to at least a portion of the upper surface of the electrode 11 while moving linearly from one side of the table 16 to the other side or in the opposite direction.

[0076] The adhesive applied from the pair of upper nozzles 17 can be explained in the same manner as the adhesive applied from the lower nozzle 173 described above.

[0077] Here, the pair of upper nozzles 17 can reciprocate left and right simultaneously or individually with respect to the table 16. More preferably, the pair of upper nozzles 17 can reciprocate left and right simultaneously with respect to the table 16. For example, when the first upper nozzle 171 applies adhesive from one side of the table 16 to the other side as shown in FIG. 5, the second upper nozzle 172 can apply adhesive from the other side of the table 16 to one side as will be described later with reference to FIG. 7.

[0078] As a result, in this embodiment, the process time of the adhesive application process by the pair of upper nozzles 17 is reduced, and the process efficiency can be further improved.

[0079] FIG. 6 is a schematic view showing a state in which a separator guide moves linearly and a second electrode is installed on a second region of a separator sheet in an electrode assembly manufacturing apparatus according to an embodiment of the present invention.

[0080] 5 and 6, in this embodiment, the folding direction of the separator sheet 122 is guided by a separator guide 125. More specifically, the separator guide 125 can move linearly back and forth left and right based on the table 16.

[0081] For example, the separation membrane guide 125 may have a form in which a pair of rolls are arranged horizontally, and the separation membrane sheet 122 may be inserted between the pair of rolls. However, the form of the separation membrane guide 125 is not limited thereto, and any form that can control the folding direction of the separation membrane sheet 122 is included in this embodiment.

[0082] In addition, the separation membrane guides 125 may be located above and below the pair of upper nozzles 17. However, the positions and number of the separation membrane guides 125 are not limited thereto, and any positions and numbers that can control the folding direction of the separation membrane sheet 122 are included in this embodiment.

[0083] Here, when the separation membrane guide 125 moves back and forth linearly toward the first transfer device 141 and the second transfer device 142 based on the table 16, the separation membrane sheet 122 is folded along the moving direction of the separation membrane guide 125, so that the separation membrane sheet 122 can cover the electrode 11.

[0084] For example, referring to Figures 5 and 6, with the first electrode 1112 installed on the first region 1221 of the separation membrane sheet 122, the separation membrane guide 125 moves linearly toward the first transfer device 141 so that the second region 1222 of the separation membrane sheet 122 covers the top of the first electrode 1112.

[0085] Here, the first region 1221 of the separation membrane sheet 122 refers to the region of the separation membrane sheet 122 where the first electrode 1112 is attached. In some cases, the first region 1221 refers to the region of the separation membrane sheet 122 where the first electrode 1112 is attached while covering the second electrode 1122. The second region 1222 refers to the region of the separation membrane sheet 122 where the second electrode 1122 is attached while covering the first electrode 1112. In other words, the first electrode 1112 can be installed on the first region 1221 of the separation membrane sheet 122, and the second electrode 1122 can be installed on the second region 1222 of the separation membrane sheet 122.

[0086] In addition, the separation membrane guide 125 may simultaneously reciprocate left and right together with the pair of upper nozzles 17 based on the table 16, or the separation membrane guide 125 and the pair of upper nozzles 17 may each reciprocate left and right.

[0087] 5 and 6, when the first upper nozzle 171 applies the adhesive to at least a portion of the upper surface of the first electrode 1112, the separation membrane guide 125 moves linearly in a direction in which the separation membrane sheet 122 covers the first electrode 1112. Furthermore, when the second upper nozzle 172 applies the adhesive to at least a portion of the upper surface of the second electrode 1122, as will be described later in FIG. 7, the separation membrane guide 125 can move linearly in a direction in which the separation membrane sheet 122 covers the second electrode 1122.

[0088] This allows the separation membrane guide 125 to be Z-folded so that the separation membrane sheet 122 covers the upper and lower parts of the electrode 11 .

[0089] More preferably, the separation membrane guide 125 and the pair of upper nozzles 17 can simultaneously reciprocate left and right based on the table 16. For example, as shown in Figures 5 and 6, when the first upper nozzle 171 applies adhesive from one side of the table 16 to the other, the separation membrane guide 125 can also move linearly from one side of the table 16 to the other to fold the separation membrane sheet 122.

[0090] As a result, the adhesive application process by the pair of upper nozzles 17 and the folding process of the separator sheet 122 by the separator guide 125 can be performed simultaneously, thereby reducing the process time and improving the process efficiency.

[0091] FIG. 7 is a schematic view showing a state in which a second upper nozzle applies adhesive to an upper portion of a second electrode while moving linearly in an electrode assembly manufacturing apparatus according to an embodiment of the present invention.

[0092] 2, 6, and 7, in the electrode assembly manufacturing apparatus 1 according to this embodiment, similar to the first electrode 1112, the second electrode 1122 can be attracted to the second header 152 and move back and forth in a straight line. For example, as shown in FIG. 6, with the second electrode 1122 attracted to the second header 152, the second header 152 can move in a straight line to be positioned above the table 16. In this case, the second electrode 1122 can be installed on the second region 1222 of the separator sheet 122. Otherwise, the second electrode 1122 and the second header 152 can be described in the same manner as the first upper nozzle 171 described above.

[0093] Also, similar to the first upper nozzle 171, the second upper nozzle 172 may perform a linear reciprocating motion based on the table 16. For example, as the second upper nozzle 172 moves from one side of the table 16 to the other, it may apply adhesive to at least a portion of the upper surface of the second electrode 1122. Otherwise, the second upper nozzle 172 may be described in the same manner as the first upper nozzle 171 described above.

[0094] Using the electrode assembly manufacturing apparatus 1, an electrode assembly manufacturing method according to an embodiment of the present invention can be performed as follows.

[0095] First, referring to Figures 1 and 2, when the first electrode sheet 1111 is unwound from the first electrode reel 111, the first cutter 131 cuts the first electrode sheet 1111 to form a plurality of first electrodes 1112 (S101).

[0096] Meanwhile, the separation membrane sheet 122 is unwound from the separation membrane reel 121 and placed on the top surface of the table 16 (S102).

[0097] Further, the lower nozzle 173 applies adhesive to the lower part of the first electrode 1112 (S103). As an example, as shown in Fig. 3, the lower nozzle applies adhesive to the lower part of the first electrode 1112 while the first header 151 is adsorbing the first electrode 1112. As another example, as shown in Fig. 4, the lower nozzle 173 applies adhesive to the lower part of the first electrode 1112 while the first transport device 141 is transporting the first electrode 1112.

[0098] 1 and 2, the first header 151 can move linearly above the table 16 while adsorbing the first electrode 1112. When the first header 151 is positioned above the table 16, as shown in FIG. 2, the first header 151 places the first electrode 1112, on which the first adhesive layer 1710 is formed, in the first region 1221 of the separator sheet 122 (S104).

[0099] 1 and 5, when the first electrode 1112 is installed in the first region 1221 of the separator sheet 122, the first upper nozzle 171 may apply adhesive to the upper part of the first electrode 1112 (S105). Here, as the first upper nozzle 171 moves toward the first transfer device 141, the second adhesive layer 1750 may be formed on the upper part of the first electrode 1112.

[0100] Also, referring to Figures 1 and 6, with at least a portion of the second adhesive layer 1750 formed on the top of the first electrode 1112, the separation membrane guide 125 moves in the same direction as the movement direction of the first upper nozzle 171, and one side of the separation membrane sheet 122 is folded so that the second region 1222 of the separation membrane sheet 122 covers the first electrode 1112 (S106).

[0101] 2, when the second electrode sheet 1121 is unwound from the second electrode reel 112, the second cutter 132 cuts the second electrode sheet 1121. This forms a plurality of second electrodes 1122. When the second transport device 142 transports the second electrode 1122, the second header 152 adsorbs the second electrode 1122. Here, a first adhesive layer 1710 formed by applying an adhesive from a lower nozzle 173 may be positioned on the bottom of the second electrode 1122 together with the first electrode 1112.

[0102] Also, as shown in FIG. 6, when the second region 1222 of the separation membrane sheet 122 covers the first electrode 1112, the second header 152 adsorbing the second electrode 1122 moves toward the top of the second region 1222 and places the second electrode 1122 on the top of the second region 1222.

[0103] 7, the second upper nozzle 172 applies adhesive to the upper part of the second electrode 1122. Here, as the second upper nozzle 172 moves toward the second transfer device 142, a second adhesive layer 1750 may be formed on the upper part of the second electrode 1122.

[0104] Then, with at least a portion of the second adhesive layer 1750 formed on the top of the second electrode 1122, the separation membrane guide 125 moves in the same direction as the movement direction of the second upper nozzle 172, and the other side of the separation membrane sheet 122 is folded so that the first region 1221 of the separation membrane sheet 122 covers the second electrode 1122.

[0105] That is, by repeating the above process, the method for manufacturing an electrode assembly according to an embodiment of the present invention can be performed.

[0106] When the electrode assembly manufacturing method according to this embodiment of the present invention is performed, adhesive is applied to the top and bottom of the electrode 11 when stacking the electrode 11 and the separator sheet 122 in a Z-folded manner, preventing the electrode 11 from coming off from its designated position.

[0107] FIG. 8 is a cross-sectional view of an electrode assembly according to one embodiment of the present invention.

[0108] Referring to Figures 7 and 8, in an electrode assembly 10 in which electrodes and separator sheets according to another embodiment of the present invention are alternately stacked, the electrode 11 includes a first electrode 1112 and a second electrode 1122, and the separator sheet 122 has a zigzag shape formed by being folded at least twice.

[0109] Here, the separation membrane sheet 122 is folded with the first electrode 1112 placed on the first region 1221 of the separation membrane sheet 122, and the second region 1222 of the separation membrane sheet 122 covers the first electrode 1112. Also, the separation membrane sheet 122 is folded with the second electrode 1122 placed on the second region 1222 of the separation membrane sheet 122, and the first region 1221 of the separation membrane sheet 122 covers the second electrode 1122.

[0110] In particular, in the electrode assembly 10 according to this embodiment, the electrodes 11 may be stacked one by one on the first region 1221 or the second region 1222 of the separator sheet 122. In this case, the electrodes 11 may be stacked in accurate positions on the separator sheet 122 after measuring whether there is any misalignment and correcting their positions as necessary. As a result, the electrode assembly 10 according to this embodiment can further improve the alignment between the electrodes 11 and the separator sheet 122.

[0111] Here, an adhesive layer 1700 is formed between the electrode 11 and the separator sheet 122. More specifically, the adhesive layer 1700 includes a first adhesive layer 1710 and a second adhesive layer 1750. The first adhesive layer 1710 may be located between the lower part of the electrode 11 and the separator sheet 122, and the second adhesive layer 1750 may be located between the upper part of the electrode 11 and the separator sheet 122.

[0112] For example, the first adhesive layer 1710 and the second adhesive layer 1750 may each be formed by applying adhesive in the form of a plurality of dots. However, as previously described in connection with the electrode assembly manufacturing apparatus 1, the form of the first adhesive layer 1710 and the second adhesive layer 1750 is not limited thereto and may be formed in various forms.

[0113] As a result, in the electrode assembly 10 according to this embodiment, an adhesive layer 1700 is formed between the electrode 11 and the separator sheet 122, and even in the case of an inexpensive separator with excessively low adhesive strength, the electrode 11 and the separator can be stably fixed to each other, preventing the electrode 11 from coming off from its fixed position. Additionally, in the electrode assembly 10 according to this embodiment, one separator sheet 122 is folded to cover the upper and lower parts of the electrode 11, thereby further improving the alignment of the electrode 11 and process efficiency.

[0114] In addition, since there is no need for a laminating process as in the past, the defect rate in the process caused by high heat and pressure can be reduced.In addition, since the laminator can be eliminated, the volume of the manufacturing equipment is reduced and the manufacturing process is simplified.

[0115] The separator according to the embodiments described herein may be a ceramic coated separator (CCS). Generally, a separator comprises a roll of film and a coating layer formed on at least one surface of the roll of film. The coating layer may contain alumina powder and a binder that holds the powder together. While a safety reinforced separator (SRS) has a large amount of binder coated on the surface of the coating layer, a CCS may not have a binder coated on the surface of the coating layer or may have a much lower binder content than an SRS. For example, in the case of a CCS separator according to the present embodiment, the binder content coated on the surface of the coating layer of the separator may be approximately 3 wt% or less. For example, the binder content coated on the surface of the coating layer of the separator may be approximately 2 wt% or less, or approximately 1 wt% or less.

[0116] When the separator is CCS, the internal electrodes included in the electrode assembly are transported in an unfixed state, which can lead to misalignment during transport. While the separator can be fixed using heat and pressure, the alignment of the internal electrodes can also be disturbed during transport using a heat and pressure fixing device after the electrode and separator stack is formed. Another drawback is that attaching the electrodes and separator using heat and pressure requires the use of expensive separators with a high binder content. In contrast, this embodiment can increase the fixing strength while preventing misalignment of the internal electrodes during transport.

[0117] FIG. 9 is an exploded perspective view of a battery cell according to one embodiment of the present invention.

[0118] 2, 8, and 9, a battery cell according to another embodiment of the present invention is a battery cell including the electrode assembly 10 described above, and includes a battery case 50 that houses the electrode assembly 10 together with an electrolyte, and an adhesive layer 1700 that dissolves in the electrolyte.

[0119] Here, a fixing member such as fixing tape 30 may be attached to the outside of the electrode assembly 10. This maintains the stacked alignment of the electrode 11 and the separator sheet 122. The electrode assembly 10 with the fixing tape 30 attached can be called the final electrode assembly 20.

[0120] The battery case 50 includes a receiving portion 60 in which the electrode assembly 10 or the final electrode assembly 20 is mounted, and a sealing portion 70 that seals the outer periphery of the receiving portion 60. For example, the battery case 50 may be a laminate sheet including a resin layer and a metal layer. More specifically, the battery case 50 may be made of a laminate sheet and may include an outer resin layer forming the outermost shell, a barrier metal layer that prevents penetration of materials, and an inner resin layer for sealing.

[0121] Furthermore, the receiving portion 60 of the battery case 50 may receive an electrolyte together with the electrode assembly 10. Here, the adhesive layer 1700 included in the electrode assembly 10 may dissolve in the electrolyte. In particular, in the battery cell according to this embodiment, the adhesive layer 1700 included in the electrode assembly 10 may dissolve in the electrolyte under high temperature and / or pressure conditions during an activation process such as a formation process.

[0122] More specifically, in the battery cell according to this embodiment, when the adhesive layer 1700 formed between the electrode 11 of the electrode assembly 10 and the separator sheet 122 dissolves in the electrolyte, little or no adhesive 14 may remain on the surface of the electrode 11.

[0123] In contrast, the separator membrane sheet 122 is generally a porous sheet, and therefore, a portion of the adhesive 14 may penetrate into the separator membrane sheet 122. However, even in the case of the adhesive layer 1700 that has penetrated into the separator membrane sheet 122, it may be mostly or completely dissolved in the electrolyte, and during this process, traces of the adhesive layer 1700 may remain on the separator membrane sheet 122.

[0124] Here, the application trace of the adhesive layer 1700 refers to a portion of the outer surface of the separator membrane sheet 122 that is deformed by the adhesive layer 1700, even though the adhesive component contained in the adhesive layer 1700 does not remain. However, the application trace of the adhesive layer 1700 is not limited thereto, and may refer to a trace that can be used to check whether or not an adhesive has been applied in various ways, such as a trace that can be checked with the naked eye. Thus, the application trace of the adhesive layer 1700 formed on the separator membrane sheet 122 may be formed in the same position as the position where the adhesive was applied.

[0125] As a result, in the battery cell of this embodiment, the adhesive layer 1700 is completely dissolved on the surface of the electrode 11 or the separator 122, and the unreacted areas caused by the adhesive layer 1700 disappear, preventing performance degradation and achieving excellent battery performance.

[0126] Although the preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements made by those skilled in the art using the basic concept of the present invention defined in the following claims also fall within the scope of the present invention. [Explanation of symbols]

[0127] 1: Electrode assembly manufacturing equipment 11: Electrode 16: Table 17: Nozzle 111: First electrode reel 112: Second electrode reel 121: Separation membrane reel 122: Separation membrane sheet 125:Separation Membrane Guide 131: First Cut 132: 2nd Cut 141:First transfer device 142:Second transfer device 151: First Header 152: Second Header 171: First upper nozzle 172: Second upper nozzle 1111: First electrode sheet 1112: 1st electrode 1121: Second electrode sheet 1122:Second electrode 1221:First area 1222:Second area 1710: 1st adhesive layer 1750: 2nd adhesive layer

Claims

1. an electrode supply unit provided with an electrode sheet on which a plurality of electrodes are formed; a separation membrane supply unit that provides a separation membrane sheet that is folded when the electrodes are installed, covers the electrodes, and is laminated with the electrodes; a table on which the electrodes are placed with the separator sheet folded between the electrodes to form an electrode assembly; A separation membrane guide that guides the folding direction of the separation membrane sheet; and a pair of upper applicators that apply adhesive to at least a portion of an upper portion of the electrode installed on the table; The separation membrane guide and the pair of upper coaters are linearly reciprocated left and right based on the table, The table is fixed.

2. The electrode supply unit includes: a first electrode reel from which a first electrode sheet on which a plurality of first electrodes are formed is unwound; and The electrode assembly manufacturing apparatus according to claim 1 , further comprising a second electrode reel from which a second electrode sheet on which a plurality of second electrodes are formed is unwound.

3. The pair of top coaters includes a first top nozzle and a second top nozzle, the first upper nozzle applies the adhesive to an upper portion of the first electrode; The electrode assembly manufacturing apparatus of claim 2 , wherein the second upper nozzle applies the adhesive to an upper portion of the second electrode.

4. The electrode assembly manufacturing apparatus according to claim 3 , wherein the first upper nozzle and the second upper nozzle are disposed on both sides of the separation membrane guide.

5. the first electrode is installed on a first region of the separation membrane sheet, The electrode assembly manufacturing apparatus according to claim 3 , wherein the second electrode is disposed on a second region of the separator sheet.

6. When the first electrode is placed on the first region of the separation membrane sheet, the first upper nozzle moves linearly on the first electrode, The electrode assembly manufacturing apparatus according to claim 5 , wherein when the second electrode is placed on the second region of the separator sheet, the second upper nozzle moves linearly above the second electrode.

7. When the first upper nozzle applies the adhesive to at least a portion of the upper surface of the first electrode, the separation membrane guide moves linearly in a direction in which the separation membrane sheet covers the first electrode, 7. The electrode assembly manufacturing apparatus of claim 6, wherein when the second upper nozzle applies the adhesive to at least a portion of the upper surface of the second electrode, the separator guide moves linearly in a direction in which the separator sheet covers the second electrode.

8. The electrode assembly manufacturing apparatus according to claim 5 , further comprising a bottom applicator that applies the adhesive to the bottom of the first electrode and the bottom of the second electrode, respectively.

9. a first header for adsorbing the first electrode and placing it in the first region; and The electrode assembly manufacturing apparatus of claim 8 , further comprising a second header that attracts and places the second electrode in the second region.

10. When the first electrode is attracted to the first header, the lower applicator applies the adhesive to a lower portion of the first electrode, The electrode assembly manufacturing apparatus of claim 9 , wherein the lower coater coats the adhesive on a lower portion of the second electrode when the second electrode is attracted to the second header.

11. a first transport device that transports the first electrode toward the table; and The electrode assembly manufacturing apparatus according to claim 8 , further comprising a second transfer device that transfers the second electrode toward the table.

12. the first transfer device includes a first groove that is open toward the first electrode, and the lower applicator applies the adhesive to a lower portion of the first electrode through the first groove; 12. The electrode assembly manufacturing apparatus of claim 11, wherein the second transfer device includes a second groove that is open toward the second electrode, and the bottom coater applies the adhesive to the bottom of the second electrode through the second groove.

13. cutting the first electrode sheet unwound from the first electrode supply unit to form a plurality of first electrodes; a step of placing a separation membrane sheet provided from a separation membrane supply unit on a table along a separation membrane guide; applying an adhesive to a lower portion of the first electrode by a lower applicator; placing the first electrode in a first region of the separator sheet; applying adhesive to an upper portion of the first electrode through a first upper nozzle; and The method for manufacturing an electrode assembly includes folding the separator sheet in a folding direction guided by the separator guide so that the second region of the separator sheet covers the first electrode.

14. After covering the top of the first electrode, cutting the second electrode sheet provided by the second electrode supply unit to form a plurality of second electrodes; applying an adhesive to a lower portion of the second electrode by a lower applicator; placing the second electrode in the second region of the separator sheet; a second upper nozzle applying adhesive to an upper portion of the second electrode; and The method of manufacturing an electrode assembly according to claim 13, further comprising folding the separator sheet in a folding direction guided by the separator guide so that the first region of the separator sheet covers the second electrode.

15. The table is fixed, The method of manufacturing an electrode assembly according to claim 14 , wherein the separation membrane guide, the first upper nozzle, and the second upper nozzle are linearly reciprocated with respect to the table.

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