Electrode assembly manufacturing apparatus and electrode assembly manufacturing method

Abstract

The present invention relates to an apparatus for manufacturing an electrode assembly and a method for manufacturing an electrode assembly.

Description

[Technical Field]

[0001] This application claims the benefit of the filing date of Korean Patent Application No. 10-2023-0000706, filed with the Korean Intellectual Property Office on January 3, 2023, the entire contents of which are incorporated herein by reference.

[0002] The present invention relates to an apparatus for manufacturing an electrode assembly and a method for manufacturing an electrode assembly. [Background technology]

[0003] Unlike primary batteries, secondary batteries are rechargeable and have the potential to be miniaturized and have large capacities. Due to technological developments and increasing demand for mobile devices, the demand for secondary batteries as an energy source is rapidly increasing.

[0004] Secondary batteries are classified into coin-type batteries, cylindrical batteries, prismatic batteries, and pouch-type batteries depending on the shape of the battery case. The electrode assembly installed inside the battery case of a secondary battery is a power generating element that can be charged and discharged and is made up of a laminated structure of electrodes and a separator.

[0005] Electrode assemblies can be broadly classified into jelly-roll types, in which a separator is interposed between sheet-like positive and negative electrodes coated with active material and wound up, stack types, in which multiple positive and negative electrodes are stacked in sequence with a separator interposed between them, and stack-and-fold types, in which stack-type unit cells are wound up with a long separator film.

[0006] Among these, an electrode assembly in which the separator is folded in a zigzag pattern and the electrodes are positioned therebetween can be manufactured, and for this purpose, a stack in which the separator is folded in a zigzag pattern and the electrodes are positioned therebetween can be manufactured.

[0007] In this case, an end of the separator last laminated on the laminate may be pulled, the end of the separator may be cut, and a predetermined length of the cut end of the separator may be wound around the laminate (winding step).Finally, the wound laminate is heated and pressurized to complete the electrode assembly.

[0008] However, during the winding process, wrinkles may occur in the stacked separator due to the influence of an air gap or static electricity, which may result in a deterioration in the performance of the completed electrode assembly. Summary of the Invention [Problem to be solved by the invention]

[0009] An object of the present invention is to provide an apparatus for manufacturing an electrode assembly and a method for manufacturing an electrode assembly. [Means for solving the problem]

[0010] One embodiment of the present invention provides an electrode assembly manufacturing apparatus for manufacturing an electrode assembly in which first and second electrodes are alternately arranged between folded separators, the apparatus including: a first electrode supply unit that supplies the first electrodes to the stack table; a second electrode supply unit that supplies the second electrodes to the stack table; a separation membrane supply unit that supplies the separation membrane to the stack table; a stack table on which the first electrodes, the separation membrane, and the second electrodes are stacked in the form of a stack in which the separation membrane that is last stacked on the stack table has an extended region for being wound in contact with one or more sides of the stack, and the first electrodes and the second electrodes are alternately arranged between the folded separators; a separation membrane winding unit that winds the separation membrane so that the extended region for being wound contacts one or more sides of the stack; and a brushing unit that heats and brushes the wound stack.

[0011] Another embodiment of the present invention provides a method for manufacturing an electrode assembly in which first and second electrodes are alternately arranged between folded separators, the method including: supplying the first electrodes to a stack table; supplying the second electrodes to the stack table; supplying the separators to the stack table; stacking the first electrodes, the separators, and the second electrodes on the stack table so that the separators last stacked on the stack table have extended regions for being wound in contact with one or more sides of the stack, and the first electrodes and the second electrodes are alternately arranged between the folded separators, to manufacture a stack including the first electrodes, the separators, and the second electrodes; winding the separators so that the extended regions for being wound contact one or more sides of the stack; and brushing the wound stack while heating. [Effects of the Invention]

[0012] The electrode assembly manufacturing apparatus and electrode assembly manufacturing method according to the embodiments of the present application can reduce the time required to manufacture the electrode assembly.

[0013] The electrode assembly manufacturing apparatus and the electrode assembly manufacturing method according to the embodiments of the present application can prevent the occurrence of wrinkles in the separator during the manufacturing process, thereby providing an electrode assembly with excellent performance. [Brief explanation of the drawings]

[0014] [Figure 1] 1 is a flow chart that schematically illustrates a step of applying a brushing element or a method of brushing according to one embodiment of the present invention. [Figure 2] 1 is a plan view illustrating an example of an apparatus for manufacturing an electrode assembly according to an embodiment of the present invention. [Figure 3] 1 is a front view showing the concept of an electrode assembly manufacturing apparatus according to an embodiment of the present invention. [Figure 4]1 is a cross-sectional view showing an example of a conventional electrode assembly. [Figure 5] 3 is a conceptual diagram illustrating a pressing process of a manufacturing method or apparatus for an electrode assembly according to an embodiment of the present invention. [Figure 6] FIG. 1(a) is a perspective view showing a first press section according to one embodiment of the present invention, and FIG. 1(b) is a perspective view showing a second press section according to one embodiment of the present invention. [Figure 7] 1 is a perspective view showing a stack table in an apparatus for manufacturing an electrode assembly according to an embodiment of the present invention; [Figure 8] 1 is a perspective view showing a first electrode mounting table in an electrode assembly manufacturing apparatus according to an embodiment of the present invention. [Figure 9] 3 is a perspective view showing a second electrode mounting table in the electrode assembly manufacturing apparatus according to one embodiment of the present invention. FIG. [Figure 10] 1 is a perspective view showing a first suction head in an electrode assembly manufacturing apparatus according to an embodiment of the present invention. [Figure 11] 3 is a bottom view showing a first suction head in the electrode assembly manufacturing apparatus according to one embodiment of the present invention. FIG. [Figure 12] 1 is a plan view showing a holding mechanism and a stack table in an electrode assembly manufacturing apparatus according to an embodiment of the present invention. [Explanation of symbols]

[0015] 10...electrode assembly 11...1st electrode 11a First electrode tab 12...Second electrode 12a Second electrode tab 14...Separation membrane 51 Gripper 51a Main body 51b...Fixed part 60 ···Second Press Department 60a, 60b: A pair of second pressure blocks 100 Electrode assembly manufacturing apparatus 110 Stack Table 111 Table body 112 Stack Table Heater 120...Separation membrane supply section 121 Separation membrane heat section 122 Separation membrane roll 130...1st electrode supply section 131 First electrode placement table 132 First electrode heater 133 First electrode roll 134 First cutter 135 First conveyor belt 136 First electrode supply head 140...Second electrode supply section 141 Second electrode placement table 142 Second electrode heater 143 Second electrode roll 144 Second cutter 145 - Second conveyor belt 146 Second electrode supply head 150 First electrode stack section 151 First suction head 151a...Vacuum inlet 151b...Bottom surface 152 First head heater 153 First moving part 160 Second electrode stack section 161 Second suction head 162 Second head heater 163 Second moving part 170 ···Holding mechanism 171 First holding mechanism 172 Second holding mechanism 180 ···Press Department 181 First pressure block 182 Second pressure block 183, 184 Press heater 190 Brushing section 190a Brushing unit 190b Brushing heating unit S ···Laminate A: Extended area of the membrane DETAILED DESCRIPTION OF THE INVENTION

[0016] Although the present invention may be embodied in many different forms, it is not intended to be limited to the embodiments set forth herein, and the present invention will be described in detail below so as to enable those skilled in the art to easily practice the present invention.

[0017] In this specification, when a part is said to "comprise" a certain component, this means that it may further include other components, rather than excluding other components, unless specifically stated to the contrary. In this specification, the term "holding mechanism" refers to a mechanism that holds the stacked material on the stack table in order to stack the first electrodes or the second electrodes during the process of manufacturing a stack in which the first electrodes, the separation membrane, and the second electrodes are stacked, with the first electrodes and the second electrodes alternately arranged between the separation membranes folded on the stack table, and its function is different from that of a gripper that holds the stacked material during the process of heating and pressurizing the stacked material.

[0018] In this specification, "winding" refers to a process of surrounding a stack of laminates with a separator that is laminated last to manufacture an electrode assembly. In this case, the separator may surround the stack while contacting one or more sides of the stack. For this reason, the portion of the separator that corresponds to the required length is defined as the "extended region" in this specification.

[0019] In this specification, the term "a laminate in which first electrodes and second electrodes are alternately arranged between folded separators" may refer to an unfinished electrode assembly before the laminate is heated and pressurized to complete the electrode assembly.

[0020] One embodiment of the present invention provides an electrode assembly manufacturing apparatus for manufacturing an electrode assembly in which first and second electrodes are alternately arranged between folded separators, the apparatus including: a first electrode supply unit that supplies the first electrodes to the stack table; a second electrode supply unit that supplies the second electrodes to the stack table; a separation membrane supply unit that supplies the separation membrane to the stack table; a stack table in which the first electrodes, the separation membrane, and the second electrodes are stacked in the form of a stack in which the separation membrane that is last stacked on the stack table has an extended region for being wound in contact with one or more sides of the stack, and the first electrodes and the second electrodes are alternately arranged between the folded separators; a separation membrane winding unit that winds the separation membrane so that the extended region for being wound contacts one or more sides of the stack; and a brushing unit that heats and brushes the wound stack.

[0021] The electrode assembly manufacturing apparatus according to the present invention includes a brushing unit that heats and brushes the wound laminate. The brushing unit can brush the entire surface of the extended region of the separator. That is, the brushing unit that heats and brushes can prevent wrinkles in the laminated separator due to the influence of air gaps or static electricity, thereby providing an electrode assembly with excellent performance.

[0022] Furthermore, since the electrode assembly can be manufactured in a continuous process without using a separate auxiliary material for fixing the electrode assembly, the time required to manufacture the electrode assembly can be reduced.

[0023] In this specification, the term "unit" refers to an interface that performs a specific function within an electrode assembly manufacturing apparatus.

[0024] In this specification, "brushing" refers to a process of spreading the surface of the wound laminate for a short period of time using a heatable roller or the like.

[0025] In one embodiment of the present invention, the brushing unit includes a brushing body that directly contacts the wound laminate and a brushing heating unit that heats the wound laminate.

[0026] The brushing body may be provided in the form of a rotating roller or a brush having bristles planted on one surface thereof. Preferably, the brushing body may be provided in the form of a plate having bristles planted on one surface thereof.

[0027] The brushing heater may generate heat for heating the laminate during brushing. Heating the laminate may prevent wrinkles in the separator laminated on the electrode assembly caused by static electricity or an air gap, thereby providing an electrode assembly with excellent performance.

[0028] The electrode assembly manufacturing apparatus according to an embodiment of the present invention may further include a temperature control unit that controls a temperature and a heating time for heating the laminate during the brushing process. The temperature control unit may include a sensor that measures a surface temperature of the laminate.

[0029] That is, the electrode assembly manufacturing apparatus according to one embodiment of the present invention may further include a temperature control unit that heats and brushes the wound laminate at a temperature of 100°C to 150°C, preferably 100°C to 120°C, for 2 seconds to 10 seconds.

[0030] In one embodiment of the present invention, the method may further include a press unit that heats and presses the brushed laminate, and a gripper that grips the brushed laminate and moves it to the press unit. The gripper is different from the holding mechanism, as described above, and may be the same as the gripper used in the first heat pressing step, as described below.

[0031] In one embodiment of the present invention, the press unit may include a pair of pressurizing blocks each including a heater.

[0032] In one embodiment of the present invention, the separation membrane winding unit may include a clamp that grips the end of the extended region of the separation membrane; a clamp moving unit that pulls the gripped extended region of the separation membrane in the direction opposite to the folded position of the separation membrane; and a rotating unit that rotates the stack held by the clamp as the extended region is pulled in the direction opposite to the folded position of the separation membrane. The rotating unit rotates the stack, allowing the extended region of the separation membrane to contact one or more sides of the stack and wind around the stack. During the process of rotating the stack, the stack may be fixed, if necessary, by the holding mechanism or a gripper, as described below.

[0033] The apparatus for manufacturing an electrode assembly according to an embodiment of the present invention may further include a separator cutting unit for cutting an end of the extended region of the separator. Since the separator supplied from the separator supply unit may be in the form of a continuous separator sheet, it is necessary to cut the end of the extended region of the separator, and the cut portion can be gripped by the clamp.

[0034] In one embodiment of the present invention, the press section may be composed of a pair of pressure blocks that move in opposite directions to each other to apply surface pressure to the laminate stacked on the table.

[0035] In this specification, the separation membrane may be supplied in the form of a separation membrane sheet.

[0036] One embodiment of the present invention provides a method for manufacturing an electrode assembly in which first and second electrodes are alternately arranged between folded separators, the method including: supplying the first electrodes to a stacking table; supplying the second electrodes to the stacking table; supplying the separators to the stacking table; stacking the first electrodes, the separators, and the second electrodes on the stacking table so that the separators last stacked on the stacking table have extended regions for being wound in contact with one or more sides of the stack, and the first electrodes and the second electrodes are alternately arranged between the folded separators, to manufacture a stack including the first electrodes, the separators, and the second electrodes; winding the separators so that the extended regions for being wound contact one or more sides of the stack; and brushing the wound stack while heating.

[0037] In this specification, the stacking of the first electrode and the second electrode alternately between the folded separator is referred to as zigzag stacking.

[0038] A method for manufacturing an electrode assembly according to an embodiment of the present invention may include gripping the laminate with a gripper and transporting the laminate for heating and pressurizing. The gripper corresponds to the gripper that grips the laminate during the heating and pressurizing process, and has a function different from that of the holding mechanism, as described above.

[0039] In one embodiment of the present invention, the step of brushing the wound laminate while heating comprises brushing the surface of the wound laminate with a brushing unit while heating the entire extended region of the separator to be wound. In this case, the brushing unit may include a brushing body and a brushing heating unit, and the brushing body may be in the form of a rotating roller or in the form of a brush with bristles planted on one or an outer surface.

[0040] Preferably, the brushing step may include the steps of: bringing a brushing body, which includes a brushing heater and has bristles attached to one or the outer surface, into contact with the entire extended area of the separator film to be wound; moving the brushing body in one direction while heating the laminate in the brushing heater; and releasing the brushing body from contact. In this case, if two or more surfaces require brushing, the above steps may be performed for each surface.

[0041] In one embodiment of the present invention, the step of brushing the wound laminate while heating it may be performed at a temperature of 100° C. to 150° C., preferably 100° C. to 120° C., for 2 to 10 seconds.

[0042] The method for manufacturing an electrode assembly according to an embodiment of the present invention may further include a heat pressing step of heating and pressing the brushed laminate.

[0043] In one embodiment of the present invention, the separator that is last stacked on the stack table has an extended region for being wound in contact with one or more surfaces of the stack, and the first electrode and the second electrode are alternately arranged between the folded separators. In this case, the step of stacking the first electrode, the separator, and the second electrode on the stack table to manufacture the stack including the first electrode, the separator, and the second electrode is (S1) stacking the second electrode on the stack table; (S2) stacking the separator on the stack table so that the separator covers an upper surface of the second electrode stacked on the stack table; (S3) stacking a first electrode on a surface of the separator covering the upper surface of the second electrode opposite to a surface in contact with the second electrode; (S4) providing the separator to cover the upper surface of the first electrode; (S5) stacking the second electrode on a surface of the separator covering the upper surface of the first electrode opposite to the surface that contacts the first electrode; and (S6) further providing the separator to cover the upper surface of the second electrode; The steps (S1) to (S6) may be repeated one or more times, and the separator that is stacked last may have an extended region for winding in contact with one or more sides of the stack. That is, in this case, the electrodes may be stacked first on the stack table, and the final electrode may be stacked after the winding.

[0044] In one embodiment of the present invention, the step of stacking the first electrodes, the separators, and the second electrodes on the stack table so that the separators that are last stacked on the stack table have an extended region for being wound in contact with one or more surfaces of the stack, and the first electrodes and the second electrodes are alternately arranged between the folded separators, to manufacture a stack including the first electrodes, the separators, and the second electrodes, comprises: (SS1) stacking separation membranes on the stack table; (SS2) stacking a first electrode on the upper surface of the separator; (SS3) providing the separator to cover the upper surface of the first electrode; (SS4) stacking the second electrode on the surface of the separator covering the upper surface of the first electrode opposite to the surface that contacts the first electrode; and (SS5) further providing the separator to cover the upper surface of the second electrode; The steps (SS1) to (SS5) are repeated one or more times, and the separation membrane that is finally stacked may have an extended region for winding in contact with one or more sides of the stack, which means that the separation membrane is first stacked on the stack table.

[0045] In one embodiment of the present invention, steps (S4), (S6), (SS3), and (SS5), i.e., steps of further supplying the separation film to cover the upper surface of the first electrode or the second electrode, may be performed by one of a method of moving the stack table left and right, a method of moving the separation film left and right, and a method of rotating the stack table.

[0046] In one embodiment of the present invention, the separation membrane may be supplied in the form of a separation membrane sheet. That is, the additional separation membrane may be supplied in a continuous form. Also, the "upper surface" may refer to the surface of the separation membrane or electrode opposite to the surface facing the stack table.

[0047] That is, in order to stack the first electrodes, the separation membrane, and the second electrodes so that the first electrodes and the second electrodes are alternately arranged between the folded separation membranes, a method in which the stack table moves left and right, a method in which the separation membrane moves left and right, or a method in which the stack table rotates may be used, and conventional techniques in the relevant field may be applied to this.

[0048] In this case, the stack can be held by a holding mechanism to maintain the alignment of the stack while the first electrode, the second electrode, and the separator are being added, so that a stack can be manufactured in which the first electrodes and the second electrodes are alternately arranged between the folded separators. As described above, the method for manufacturing an electrode assembly according to an embodiment of the present invention may further include a heat pressing step of heating and pressing the brushed laminate along the lamination axis.

[0049] In one embodiment of the present invention, the heat pressing step of heating and pressing the brushed laminate may include the steps of gripping the brushed laminate with a gripper and moving it between a pair of pressure blocks, each of which includes a heater; removing the gripper from the laminate; after removing the gripper, moving the pair of pressure blocks toward each other to apply surface pressure to the laminate; and heating the laminate with the heater.

[0050] Hereinafter, the laminate that is heated and pressed in the heat press step may refer to the brushed laminate.

[0051] In one embodiment of the present invention, the heat pressing step of applying heat and pressure along the lamination axis may include the steps of: moving the laminate between a pair of pressure blocks including a press heater; moving the pair of pressure blocks in directions opposite to each other along the lamination axis to apply surface pressure to the laminate; and heating the laminate with the press heater.

[0052] The method for manufacturing an electrode assembly according to an embodiment of the present invention may further include the step of stopping the gripping of the grippers before the heat pressing step.

[0053] More specifically, in one embodiment of the present invention, the heat pressing step of heating and pressurizing the laminate may include a first heat pressing step of gripping the laminate with grippers and heating and pressurizing the laminate; and a second heat pressing step of, after the first heat pressing step, stopping the gripping by the grippers and heating and pressurizing the laminate.

[0054] In one embodiment of the present invention, the first heat pressing step may include the steps of: pressing the upper surface of the laminate using a gripper to fix the laminate; moving the laminate fixed by the gripper between a pair of pressure blocks including a press heater; moving the pair of pressure blocks in directions opposite to each other along the lamination axis of the laminate to apply surface pressure to the fixed laminate; and heating the fixed laminate by the press heater.

[0055] In one embodiment of the present invention, the second heat pressing step may include the steps of: stopping the heating and pressing of the laminate after the first heat pressing step; separating the grippers from the laminate; moving the laminate from which the grippers have been separated between a pair of pressure blocks including a press heater; moving the pair of pressure blocks in opposite directions along the lamination axis of the laminate from which the grippers have been separated to pressurize the laminate; and heating the laminate with the press heater.

[0056] In one embodiment of the present invention, the pressurizing block used in the first heat pressing step may have grooves corresponding to the grippers.

[0057] In one embodiment of the present invention, the step of moving the gripper away from the stack may include the steps of: ceasing to apply pressure to the top surface of the stack using the gripper; and moving the gripper away from the stack.

[0058] In addition, in the heat pressing step (including the first and second heat pressing steps), the step of moving the laminate between a pair of pressure blocks including a press heater may include not only moving the laminate itself but also moving the laminate together with a stack table. In this case, the objects to be heated and pressed by the pair of pressure blocks and the press heater may refer to the laminate and the stack table.

[0059] In one embodiment of the present invention, the first heat pressing step may involve heating and pressing the laminate at a temperature of 65°C to 90°C and a pressure of 1 MPa to 3 MPa for 10 to 30 seconds, or more preferably at a temperature of 65°C to 75°C and a pressure of 1.5 MPa to 2 MPa for 10 to 20 seconds.

[0060] In one embodiment of the present invention, the secondary heat pressing step may involve heating and pressing the laminate at a temperature of 50°C to 90°C and a pressure of 1 MPa to 6 MPa for 5 to 60 seconds, preferably at a temperature of 65°C to 90°C and a pressure of 1.5 MPa to 6 MPa for 5 to 30 seconds, and more preferably at a temperature of 65°C to 85°C and a pressure of 3 MPa to 5.5 MPa for 7 to 25 seconds.

[0061] When heating and pressurizing are performed while satisfying the above conditions, the first electrode, separator, and second electrode are easily bonded to each other in the laminate of the first electrode, separator, and second electrode without damaging the first electrode, separator, and second electrode, and the manufactured electrode assembly has excellent performance.

[0062] In one embodiment of the present invention, the temperature, pressure, and time conditions of the heat pressing step can be the same as those of the second heat pressing step. That is, the heat pressing step may involve heating and pressing the laminate under temperature conditions of 50°C to 90°C and pressure conditions of 1 MPa to 6 MPa for 5 to 60 seconds, preferably under temperature conditions of 65°C to 90°C and pressure conditions of 1.5 MPa to 6 MPa for 5 to 30 seconds. More preferably, the laminate may be heated and pressed under temperature conditions of 65°C to 85°C and pressure conditions of 3 MPa to 5.5 MPa for 7 to 25 seconds.

[0063] In one embodiment of the present invention, the step of brushing the wound laminate while heating may be performed only on the area of the laminate where the winding has been performed.

[0064] In one embodiment of the present invention, the step of winding the separation membrane so that the extended region to be wound contacts one or more surfaces of the stack may include the steps of gripping an end of the extended region of the last stacked separation membrane; pulling the gripped extended region of the separation membrane in a direction opposite to the folded position of the separation membrane; and rotating the gripped stack while the extended region is pulled in a direction opposite to the folded position of the separation membrane. As described above, by rotating the stack, the extended region of the separation membrane contacts one or more surfaces of the stack, allowing winding to surround the stack. The gripping of the end of the extended region may be performed by the clamp described above, and the rotating step may be performed by the rotating unit and holding mechanism or gripper described above.

[0065] Hereinafter, an electrode assembly manufacturing apparatus and an electrode assembly manufacturing method according to one embodiment of the present invention will be described in more detail.

[0066] FIG. 1 is a schematic diagram illustrating a brushing method or a step of applying a brushing unit according to one embodiment of the present invention. Specifically, electrode assemblies 10 are stacked, and the end of the last stacked separator 14 is cut using a separator cutting unit (not shown). This cutting allows for the formation of an extended region A of the separator. The end of the extended region A of the last stacked separator 14 can then be gripped by a clamp 1. While maintaining the grip of the clamp 1, the stack S is rotated using a rotating unit (not shown). As a result, the extended region A of the last stacked separator 14 comes into contact with one or more sides of the stack S and surrounds the stack S, completing the winding process. During this process, the stack S can be fixed using a holding mechanism 170 or a gripper 51, as needed.

[0067] Once winding is complete, the brushing unit 190 can move toward the stack S to perform brushing. Specifically, a brushing body 190a including a brushing heater 190b can be brought into contact with the surface of the wound stack S, and the stack can be heated by the brushing heater 190b while the brushing body 190a in contact with the stack moves in one direction to perform brushing. In this case, if two or more surfaces require brushing, brushing can be performed for each surface. Once brushing is complete, the brushing body 190a can be released from contact. That is, the brushing unit 190 can be moved to separate the brushing body from the stack. In this case, the heating temperature can be within the above-mentioned temperature range.

[0068] Fig. 2 is a plan view illustrating an exemplary apparatus for manufacturing an electrode assembly according to an embodiment of the present invention, and Fig. 3 is a front view illustrating the concept of the apparatus for manufacturing an electrode assembly according to an embodiment of the present invention. For convenience, Fig. 2 omits the holding mechanism 170 and the pressing unit 180 shown in Fig. 3, and Fig. 3 omits the separation membrane supply unit 120 shown in Fig. 2.

[0069] 2 and 3, an electrode assembly manufacturing apparatus 100 according to an embodiment of the present invention includes a stack table 110, a separation membrane supply unit 120 that supplies a separator 14 while heating it, a first electrode supply unit 130 that supplies a first electrode 11 while heating it, a second electrode supply unit 140 that supplies a second electrode 12 while heating it, a first electrode stacking unit 150 that stacks the first electrode 11 on the stack table 110, a second electrode stacking unit 160 that stacks the second electrode 12 on the stack table 110, and a pressing unit 180 that bonds the first electrode 11, the separator 14, and the second electrode 12. The electrode assembly manufacturing apparatus 100 according to an embodiment of the present invention may further include a holding mechanism 170 that secures the first electrode 11 and the second electrode 12 when they are stacked on the stack table 110. The apparatus also includes a brushing unit 190 that brushes the surface of the stack while heating it after winding the stack.

[0070] FIG. 4 is a cross-sectional view illustrating an example of an electrode assembly manufactured by an apparatus for manufacturing an electrode assembly or a method for manufacturing an electrode assembly according to an embodiment of the present invention.

[0071] 1 to 4, an apparatus 100 for manufacturing an electrode assembly according to an embodiment of the present invention is an apparatus for manufacturing an electrode assembly 10 by stacking a first electrode 11, a separator 14, and a second electrode 12.

[0072] Referring to FIG. 3, the electrode assembly 10 may be formed as a chargeable / dischargeable power generating element in the form of an alternately stacked assembly of a first electrode 11, a separator 14, and a second electrode 12. Here, the electrode assembly 10 may be formed, for example, in such a manner that the separator 14 is folded in a zigzag pattern, and the first electrodes 11 and the second electrodes 12 are alternately arranged between the folded separators 14. In this case, the electrode assembly 10 may be provided in such a manner that the separators 14 surround the outermost corners. That is, the electrode assembly 10 may be provided in a wound state. More specifically, after winding of an unfinished electrode assembly is completed, the unfinished electrode assembly may be brushed as described in FIG. 1, and then heated and pressurized to form the completed electrode assembly 10.

[0073] Meanwhile, the first electrode supply unit 130 may further include a first electrode roll 133 on which the first electrode 11 is wound in a sheet state, a first cutter 134 that cuts the sheet-like first electrode 11 wound on the first electrode roll 133 at regular intervals as it is unwound and supplied to form first electrodes 11 of a predetermined size, a first conveyor belt 135 that moves the first electrodes 11 cut by the first cutter 134, and a first electrode supply head 136 that vacuum-sucks the first electrodes 11 transported by the first conveyor belt 135 and places them on the first electrode placement table 131. Here, when cutting the sheet-like first electrodes 11, the first cutter 134 may cut the first electrodes 11 so that first electrode leads or first electrode tabs are formed protruding from the ends.

[0074] The second electrode supply unit 140 may further include a second electrode roll 143 on which the second electrode 12 is wound in a sheet state, a second cutter 144 that cuts the sheet-like second electrode 12 wound on the second electrode roll 143 at regular intervals as it is unwound and supplied to form second electrodes 12 of a predetermined size, a second conveyor belt 145 that moves the second electrodes 12 cut by the second cutter 144, and a second electrode supply head 146 that vacuum-sucks the second electrodes 12 transported by the second conveyor belt 145 and places them on the second electrode placement table 141. Here, when cutting the sheet-like second electrode 12, the second cutter 144 may cut the second electrode 12 so that second electrode leads or second electrode tabs are formed protruding from the ends.

[0075] 1 to 4, the operation of the electrode assembly manufacturing apparatus 100 according to one embodiment of the present invention is such that the separation membrane 14 wound around the separation membrane roll 122 is supplied through the separation membrane heating unit 121. That is, the separation membrane 14 is heated while passing through the separation membrane heating unit 121, and the heated separation membrane 14 is supplied to the stack table 110. The separation membrane 14 supplied in this manner is stacked on the stack table 110, and the heated stack table 110 heats the separation membrane 14.

[0076] Then, the first electrode 11 is heated and supplied from the first electrode supply unit 130 to the first electrode stack unit 150, where the first electrode 11 is heated and stacked on the upper surface of the separation membrane 14 stacked on the stack table 110.

[0077] At this time, the holding mechanism 170 presses the upper surface of the first electrode 11 to fix the first electrode 11 so that it does not come off the stack table 110.

[0078] Thereafter, when the stack table 110 rotates toward the second electrode stack unit 160 , the separation membrane 14 is supplied and subsequently covers the upper surface of the first electrode 11 .

[0079] Then, the second electrode 12 heated and supplied from the second electrode supply unit 140 is stacked by the second electrode stack unit 160 on the portion of the separation membrane 14 covering the upper surface of the first electrode 11. Here, in the second electrode stack unit 160, the second suction head 161 applies pressure to the second electrode 12 while heating it, thereby continuously heating the second electrode 12.

[0080] At this time, after the holding mechanism 170 that is applying pressure to the upper surface of the first electrode 11 is released from the pressure application area, pressure is applied to the upper surface of the second electrode 12 to prevent the stack including the second electrode 12 from being released from the stack table 110.

[0081] Thereafter, the process of stacking the first electrode 11 and the second electrode 12 is repeated, and the separator 14 is zigzag folded to form a stack in which the separator 14 is positioned between the first electrode 11 and the second electrode 12. In this case, the extended region of the separator 14 may be used to surround the outermost corners of the stack, using the extended region of the separator that is stacked last. In this case, the extended region of the separator 14 does not have to surround all sides of the stack. After the winding of the stack is completed, brushing is performed as described with reference to FIG. 1, and the stack is heated and pressurized in a press unit 180 as described below, to complete the electrode assembly 10.

[0082] FIG. 5 is a perspective view illustrating an example of a press unit of an apparatus for manufacturing an electrode assembly according to an embodiment of the present invention, and a state in which the press unit presses a laminate in the apparatus for manufacturing an electrode assembly according to an embodiment of the present invention.

[0083] 1 to 3 and 5, the laminate S manufactured as described above is transferred to a press unit 180, where heat and pressure are applied to the laminate S to bond the heated first electrode 11, separator 14, and second electrode 12 together, thereby manufacturing an electrode assembly 10. In this case, heat and pressure are applied to the heated first electrode 11, separator 14, and second electrode 12 through the press unit 180, thereby heat-sealing them together. Here, the manufactured laminate refers to a laminate that has been wound and brushed in the manner described with reference to FIG.

[0084] The electrode assembly manufacturing apparatus 100 according to one embodiment of the present invention configured as described above stacks the first electrode 11, the separator 14, and the second electrode 12 while heating them, and then applies heat and pressure in the press unit 180 to bond the first electrode 11, the separator 14, and the second electrode 12 together, thereby preventing loosening of the folding of the electrode assembly 10 and preventing the first electrode 11 and the second electrode 12 from shifting in their stacking positions in the electrode assembly 10.

[0085] More specifically, the press unit 180 may include a pair of pressure blocks 181, 182, and a stack of the first electrode 11, the separator 14, and the second electrode 12 may be disposed between the pair of pressure blocks 181, 182. Thereafter, the pair of pressure blocks 181, 182 are moved in directions facing each other, and the press unit 180 heats and presses the stack, thereby bonding the stacked first electrode 11, the separator 14, and the second electrode 12 together.

[0086] Furthermore, the press unit 180 further includes press heaters 183 and 184 that heat the pair of pressure blocks 181 and 182, which can heat and press the laminate. This allows for better thermal fusion between the first electrode 11, the separator 14, and the second electrode 12 in the laminate, resulting in stronger adhesion.

[0087] The pair of pressure blocks 181, 182 may be formed so that the horizontal and vertical lengths of the pressure surfaces are longer than the horizontal and vertical lengths of the laminate. The pair of pressure blocks 181, 182 may include a first pressure block 181 and a second pressure block 182, which may be formed as rectangular parallelepiped square blocks.

[0088] The press section may further include a pair of pressure blocks and a press heater that heats the pressure blocks, and the pair of pressure blocks may move in directions opposite to each other to apply surface pressure to the laminate, and the laminate may be heated by the press heater.

[0089] In this case, in one embodiment of the present invention, the pair of pressurizing blocks may include the press heater therein.

[0090] In one embodiment of the present invention, the press unit may include a first press unit and a second press unit. Specifically, the first press unit and the second press unit may be used in the first heat pressing step and the second heat pressing step, respectively, and the same description as above may be applied.

[0091] In one embodiment of the present invention, the first press unit may include a pair of first press blocks, and the press surfaces of the pair of first press blocks may include grooves shaped to correspond to the grippers, and the press surfaces other than the grooves may be flat. That is, the first press unit may be used in the first heat pressing step described above.

[0092] In one embodiment of the present invention, the second press unit may include a pair of second press blocks, and the press surfaces of the pair of second press blocks may be flat. That is, the second press unit may be used in the second heat pressing step.

[0093] FIG. 6(a) is a perspective view showing a first press section 50 according to one embodiment of the present invention, and FIG. 6(b) is a perspective view showing a second press section 60 according to one embodiment of the present invention.

[0094] 6(a), the first press unit 50 may apply heat and pressure to the laminate S while it is fixed by the gripper 51. The first press unit 50 is made up of a pair of first pressure blocks 50a and 50b, and the pressure surfaces of the pair of first pressure blocks 50a and 50b are all flat except for a groove having a shape corresponding to the fixing portion 51b of the gripper 51.

[0095] The gripper 51 may include a main body 51a that corresponds to the length x and height y of the stack S or is wider than the length x and height y of the stack S, and a plurality of fixing portions 51b that are provided on one surface of the main body 51a and are provided in the shape of a pillar or plate along the width z direction of the stack S. Here, the length x of the stack S may refer to the longest part from one end to the other end of the stack S, the height y may refer to the distance in the stacking direction of the stack S, and the width z may refer to the distance across the top surface of the stack S.

[0096] The fixing part 51b can be adjusted in position along the height direction of the main body 51a, and the fixing part 51b can contact the upper and lower surfaces of the laminate S to fix the laminate S. Thereafter, a pair of first pressure blocks 50a and 50b included in the first press part 50 move in directions opposite to each other and apply surface pressure to at least one of the laminate S and the gripper 51, thereby bonding the electrodes and the separator included in the laminate S.

[0097] 6(b), the second press unit 60 may finally heat and press the laminate S that has been primarily heated and pressed by the first press unit 50. The second press unit 60 includes a pair of second press blocks 60a, 60b, which move in opposite directions to each other and apply surface pressure to the laminate S. In addition, the pair of second press blocks 60a, 60b included in the second press unit 60 may all have flat pressure surfaces that come into contact with and press the laminate S.

[0098] 1 to 3 and 7, the stack table 110 may have first electrodes 11, separation membranes 14, and second electrodes 12 stacked on it such that the first electrodes 11 and the second electrodes 12 are alternately arranged between the folded separation membranes 14.

[0099] The stack table 110 may also include a table body 111 on which the first electrode 11, the separation membrane 14, and the second electrode 12 are stacked, and a stack table heater 112 that heats the table body 111 and thereby heats the stacked stack S.

[0100] The first electrode 11 may be a positive electrode and the second electrode 12 may be a negative electrode, but the present invention is not necessarily limited to this. For example, the first electrode 11 may be a negative electrode and the second electrode 12 may be a positive electrode.

[0101] FIG. 8 is a perspective view showing a first electrode mounting table in an electrode assembly manufacturing apparatus according to an embodiment of the present invention.

[0102] 1 to 3 and 8, the first electrode supply unit 130 can supply the first electrode 11 to the first electrode stack unit 150 while heating the first electrode 11.

[0103] The first electrode supply unit 130 may also include a first electrode placing table 131 on which the first electrode 11 is placed before being stacked on the stack table 110 by the first electrode stack unit 150, and a first electrode heater 132 that heats the first electrode placing table 131 and thereby heats the first electrode 11.

[0104] Meanwhile, the first electrode supply unit 130 may further include a first electrode roll 133 on which the first electrode 11 is wound in a sheet state, a first cutter 134 that cuts the sheet-like first electrode 11 wound around the first electrode roll 133 at regular intervals as it is unwound and supplied to form first electrodes 11 of a predetermined size, a first conveyor belt 135 that moves the first electrodes 11 cut by the first cutter 134, and a first electrode supply head 136 that vacuum-sucks the first electrodes 11 transported by the first conveyor belt 135 and places them on the first electrode placement table 131. Here, when cutting the sheet-like first electrodes 11, the first cutter 134 may cut them so that first electrode tabs 11a are formed protruding from the ends.

[0105] FIG. 9 is a perspective view showing a second electrode mounting table in an electrode assembly manufacturing apparatus according to an embodiment of the present invention.

[0106] 1 to 3 and 9, the second electrode supply unit 140 can supply the second electrode 12 to the second electrode stack unit 160 while heating it.

[0107] The second electrode supply unit 140 may also include a second electrode placing table 141 on which the second electrode 12 is placed before being stacked on the stack table 110 by the second electrode stack unit 160, and a second electrode heater 142 that heats the second electrode placing table 141 and thereby heats the second electrode 12.

[0108] Meanwhile, the second electrode supply unit 140 may further include a second electrode roll 143 on which the second electrode 12 is wound in a sheet state, a second cutter 144 that cuts the sheet-like second electrode 12 wound on the second electrode roll 143 at regular intervals as it is unwound and supplied to form second electrodes 12 of a predetermined size, a second conveyor belt 145 that moves the second electrodes 12 cut by the second cutter 144, and a second electrode supply head 146 that vacuum-sucks the second electrodes 12 transported by the second conveyor belt 145 and places them on the second electrode placement table 141. Here, when cutting the sheet-like second electrode 12, the second cutter 144 may cut the second electrode 12 so that second electrode tabs 12a are formed protruding from the ends.

[0109] In one embodiment of the present invention, the first electrode stack section may include a first suction head that vacuum-sucks the first electrode placed on the first electrode placing table, and the second electrode stack section may include a second suction head that vacuum-sucks the second electrode placed on the second electrode placing table.

[0110] FIG. 10 is an oblique view showing a first suction head in an electrode assembly manufacturing apparatus according to one embodiment of the present invention, and FIG. 11 is a bottom view showing the first suction head in an electrode assembly manufacturing apparatus according to one embodiment of the present invention.

[0111] 1 to 3, 10 and 11, the first electrode stacking unit 150 can stack the first electrodes 11 on the stack table 110. As shown in FIG.

[0112] The first electrode stack unit 150 may include a first suction head 151 and a first moving unit 153 .

[0113] The first suction head 151 can vacuum-suck the first electrode 11 placed on the first electrode placement table 131. In this case, the first suction head 151 has a vacuum suction port 151a formed on a bottom surface 151b thereof, and can suck the first electrode 11 through the vacuum suction port 151a to fix the first electrode 11 to the bottom surface 151b of the first suction head 151. Here, the first suction head 151 may have a passage formed therein that connects the vacuum suction port 151a to a vacuum suction device (not shown).

[0114] The first moving unit 153 can move the first suction head 151 to the stack table 110 so that the first suction head 151 can stack the first electrode 11 placed on the first electrode placing table 131 on the stack table 110.

[0115] The second electrode stacking unit 160 may stack the second electrodes 12 on the stack table 110. Here, the second electrode stacking unit 160 may have the same structure as the first electrode stacking unit 150. In this case, the second electrode stacking unit 160 may include a second suction head 161 and a second moving unit 163.

[0116] The second suction head 161 can vacuum-suck the second electrode 12 placed on the second electrode placement table 141 .

[0117] The second moving unit 163 can move the second suction head 161 to the stack table 110 so that the second suction head 161 can stack the second electrode 12 placed on the second electrode placing table 141 on the stack table 110.

[0118] FIG. 12 is a plan view showing a holding mechanism and a stack table in an apparatus for manufacturing an electrode assembly according to one embodiment of the present invention.

[0119] Referring to Figures 1 to 3 and 12, the holding mechanism 170 can grasp the first electrode 11 or the second electrode 12 and fix it to the stack table 110 when the first electrode 11 or the second electrode 12 is stacked on the stack table 110.

[0120] In addition, when stacking the first electrode 11 on the stack table 110, the holding mechanism 170 may apply pressure to the upper surface of the first electrode 11 stacked on the uppermost side of the stack table 110 to fix it, and when stacking the second electrode 12 on the stack table 110, the holding mechanism 170 may apply pressure to the upper surface of the second electrode 12 stacked on the uppermost side of the stack table 110 to fix it. In addition, the holding mechanism 170 may apply pressure to the upper surface of the stack of the first electrode 11, the separator 14, and the second electrode 12 stacked on the stack table 110 to fix it.

[0121] That is, when the first electrode 11 and the second electrode 12 are positioned and stacked between the separation membranes 14 to form a stack, the holding mechanism 170 holds the surface located at the top of the stack by applying pressure toward the stack table 110, thereby preventing the stack from coming off the stack table 110.

[0122] Meanwhile, the holding mechanism 170 may include, for example, a first holding mechanism 171 and a second holding mechanism 172, and may fix both sides of the first electrode 11 or the second electrode 12.

[0123] As described above, when zigzag folding is performed while the stack table 110 is rotating, for example, after the holding mechanism 170 grasps the first electrode 11 or the second electrode 12, when the stack table 110 rotates, the separation membrane 14 can be loosened from the separation membrane roll 122 in proportion to the amount of rotation of the stack table 110 and supplied to the stack table 110 side.

[0124] Meanwhile, for example, the holding mechanism 170 and the stack table 110 may be connected or coupled to a rotation device (not shown), whereby when the holding mechanism 170 grips the first electrode 11 or the second electrode 12, the rotation device can rotate the holding mechanism 170 and the stack table 110.

[0125] Thereafter, when the stacking of the first electrode 11 and the second electrode 12 between the separators 14 is completed, the extended region of the lastly stacked separator may be used to surround the outermost corners of the stack. In this case, the extended region of the separator 14 does not have to surround the entire surface of the stack. After the winding of the stack is completed, brushing may be performed as described with reference to FIG. 1, and the upper and lower surfaces of the brushed stack may be heated and pressed by the press unit described above.

[0126] An apparatus for manufacturing an electrode assembly according to another embodiment of the present invention may further include a vision device for inspecting the first electrode or the second electrode.

[0127] That is, an electrode assembly manufacturing apparatus according to another embodiment of the present invention includes a stack table, a separation membrane supply unit that supplies a separation membrane to the stack table, a first electrode supply unit that supplies a first electrode to the stack table, a second electrode supply unit that supplies a second electrode to the stack table, a first electrode stacking unit that stacks the first electrode on the stack table, a second electrode stacking unit that stacks the second electrode on the stack table, a press unit that bonds between the first electrode, the separation membrane, and the second electrode 12, and a holding mechanism that fixes the first electrode and the second electrode when they are stacked on the stack table, and may further include a rotation unit that rotates the stack table and a vision device that vision-inspects the first electrode and the second electrode. That is, compared to the electrode assembly manufacturing apparatus according to the above-described embodiment, it differs in that it further includes a rotation unit and a vision device.

[0128] More specifically, in an electrode assembly manufacturing apparatus according to another embodiment of the present invention, the vision device may include a first camera and a second camera.

[0129] The first camera (not shown) may photograph the first electrode placed on the first electrode placement table in the first electrode supply unit 130, and the second camera may photograph the second electrode placed on the second electrode placement table in the second electrode supply unit.

[0130] The image information obtained from the first and second cameras can be used to inspect the quality of the lamination of the first and second electrodes, including the placement position, size, and lamination state of the first and second electrodes.

[0131] The rotating unit can rotate the stack table in one direction and the other direction. Here, a first electrode stack unit may be provided on one side of the rotating unit, and a second electrode stack unit may be provided on the other side of the rotating unit.

[0132] In addition, the rotating unit can rotate the stack table to one side to face the first suction head when stacking the first electrode, and can rotate the stack table to the other side to face the second suction head when stacking the second electrode.

[0133] In addition, the rotating unit may alternately rotate the stack table toward the first electrode stack unit and the second electrode stack unit, thereby enabling zigzag folding in a manner in which the separator is positioned between the first electrode and the second electrode.

[0134] For reference, in order to stack the first electrodes, the separation membrane, and the second electrodes so that the first electrodes and the second electrodes are alternately arranged between the folded separation membranes, a method in which the stack table moves left and right, a method in which the separation membrane moves left and right, or a method in which the stack table rotates may be used, and conventional techniques in the field may be applied to this.

[0135] In one embodiment of the present invention, the length of the long side of the electrode assembly may be 500 mm or more. The long side of the electrode assembly means the length in the direction perpendicular to the supply direction of the separator supplied during the manufacture of the electrode assembly.

[0136] In one embodiment of the present invention, the negative electrode includes a negative electrode current collector and a negative electrode active material. The negative electrode current collector has a thickness of, for example, 3 to 500 μm. Such a negative electrode current collector is not particularly limited as long as it does not cause a chemical change in the battery and has conductivity. For example, copper, stainless steel, aluminum, nickel, titanium, fired carbon, a surface-treated product with carbon, nickel, titanium, silver, etc. on the surface of copper or stainless steel, an aluminum-cadmium alloy, etc. may be used. Also, similar to the positive electrode current collector described later, fine irregularities can be formed on the surface to strengthen the bonding force of the negative electrode active material, and it may be used in various forms such as films, sheets, foils, nets, porous bodies, foams, non-woven fabrics, etc.

[0137] The negative electrode active material is, for example, carbon such as non-graphitizable carbon and graphite-based carbon; LixFe2O3 (0 ≦ x ≦ 1), Li x WO2 (0 ≦ x ≦ 1), Sn x Me 1-x Me' y O z (Me: Mn, Fe, Pb, Ge; Me': Al, B, P, Si, Group 1, Group 2, Group 3 elements of the periodic table, halogen; 0 < x ≦ 1; 1 ≦ y ≦ 3; 1 ≦ z ≦ 8) metal composite oxides, lithium metal, lithium alloys, silicon-based alloys, tin-based alloys; oxides such as SnO, SnO2, PbO, PbO2, Pb2O3, Pb3O4, Sb2O3, Sb2O4, Sb2O5, GeO, GeO2, Bi2O3, Bi2O4, Bi2O5; conductive polymers such as polyacetylene; Li-Co-Ni-based materials, etc. may be used.

[0138] The "upper surface" of the electrode assembly 10 may refer to the uppermost position of the electrode assembly 10 in the stacking direction of the electrode assemblies. Furthermore, the "lower surface" of the electrode assembly 10 may refer to the lowermost position of the electrode assembly 10 in the stacking direction of the electrode assemblies.

[0139] In one embodiment of the present invention, the lower layer region may contain natural graphite as the negative electrode active material, and the upper layer region may contain artificial graphite as the negative electrode active material.

[0140] In one embodiment of the present invention, the lower layer region and the upper layer region may each independently further contain a silicon-based compound as a negative electrode active material.

[0141] In one embodiment of the present invention, the silicon-based compound is SiO x (0≦x≦2) and SiC.

[0142] In one embodiment of the present invention, the silicon-based compound is SiO x (x=0), SiO x (0≦x≦2) and SiC.

[0143] In one embodiment of the present invention, the silicon-based compound is SiO 2 based on 100 parts by weight of the silicon-based compound. x The negative electrode of the present invention may contain 70 parts by weight or more, or 80 parts by weight or more of (x=0). That is, the negative electrode of the present invention is characterized by a high content of pure Si.

[0144] In one embodiment of the present invention, the negative electrode may be manufactured by applying a lower layer slurry containing a lower layer negative electrode active material to a current collector and drying the slurry to form a lower layer region, and then applying an upper layer slurry containing an upper layer negative electrode active material to the lower layer region and drying the slurry to form an upper layer region.

[0145] That is, one embodiment of the present invention may provide a method for manufacturing a negative electrode, including the steps of: preparing a lower layer slurry containing a lower layer negative electrode active material; and an upper layer slurry containing an upper layer negative electrode active material; coating one surface of a negative electrode current collector with the lower layer slurry, and simultaneously or after a predetermined time interval, coating the upper layer slurry on the lower layer slurry; and simultaneously drying the coated lower layer slurry and upper layer slurry to form an active material layer.

[0146] In this case, a mixed region (intermixing) where different types of active materials are mixed may exist at the contact area between the lower layer region and the upper layer region of the negative electrode. This is because, when an active material layer is formed by coating a lower layer slurry containing a lower layer negative electrode active material and an upper layer slurry containing an upper layer negative electrode active material simultaneously or successively with a very short time interval on a current collector and then drying them simultaneously, a predetermined mixed region is generated at the interface where the lower layer slurry and the upper layer slurry come into contact before drying, and then drying causes this mixed region to form a layer in the mixed region.

[0147] In one embodiment of the present invention, in the active material layer of the negative electrode, the weight ratio (or ratio of loading amounts per unit area) of the upper layer region to the lower layer region may be 20:80 to 50:50, specifically 25:75 to 50:50.

[0148] The thicknesses of the lower and upper regions of the active material layer of the negative electrode of the present invention may not be exactly the same as the thicknesses of the coated lower layer slurry and the coated upper layer slurry, but the thickness ratio of the lower and upper regions of the active material layer of the negative electrode of the present invention finally obtained after the drying or selective rolling process may be the same as the thickness ratio of the coated lower layer slurry and the coated upper layer slurry.

[0149] In one embodiment of the present invention, in the step of coating one surface of the negative electrode current collector with the lower layer slurry and simultaneously or after a predetermined time lag, coating the upper layer slurry on the lower layer slurry, the predetermined time lag may be 0.6 seconds or less, or 0.02 to 0.6 seconds, or 0.02 to 0.06 seconds, or 0.02 to 0.03 seconds. Most preferably, it may be 0 seconds. That is, simultaneous coating may be most preferable. That is, since the time lag between the coating of the lower layer slurry and the upper layer slurry is due to the coating equipment, it may be more preferable to coat the lower layer slurry and the upper layer slurry simultaneously. In this case, the method of coating the lower layer slurry and the upper layer slurry may use an apparatus such as a double slot die.

[0150] In one embodiment of the present invention, the step of simultaneously drying the coated lower layer slurry and upper layer slurry to form an active material layer may include simultaneously drying the coated lower layer slurry and upper layer slurry, and rolling the active material layer after the drying step. In this case, the rolling step may be performed by a method commonly used in the art, such as roll pressing, at a pressure of 1 MPa to 20 MPa and a temperature of 15°C to 30°C, but is not limited thereto.

[0151] In this case, the step of simultaneously drying the coated lower layer slurry and upper layer slurry to form an active material layer may be carried out by a method commonly used in the art using a combination of a hot air dryer and an infrared dryer.

[0152] In one embodiment of the present invention, the weight % of the first binder polymer in the solid content of the underlayer slurry may be the same as or greater than the weight % of the second binder polymer in the solid content of the overlayer slurry.

[0153] Specifically, in one embodiment of the present invention, the weight percentage of the first binder polymer in the solid content of the lower layer slurry may be 1.0 to 4.2 times, 1.5 to 3.6 times, or 1.5 to 3 times greater than the weight percentage of the second binder polymer in the solid content of the upper layer slurry.

[0154] In this case, when the weight percentage of the first binder in the coated lower layer slurry and the weight percentage of the second binder in the coated upper layer slurry satisfy this range, the amount of binder in the lower layer region is not too small, so detachment of the electrode layer does not occur, and the amount of binder in the upper layer region is not too large, so the resistance of the upper layer of the electrode is reduced, which may be advantageous for fast charging performance.

[0155] In one embodiment of the present invention, the weight percentage of the first binder polymer in the solid content of the lower layer slurry may be 2 wt% to 30 wt%, or 5 wt% to 20 wt%, and the weight percentage of the second binder polymer in the solid content of the upper layer slurry may be 0.5 to 20 wt%, or 1 to 15 wt%, or 1 wt% to 10 wt%, or 2 wt% to 5 wt%.

[0156] In one embodiment of the present invention, the total ratio (weight %) of the first binder polymer and the second binder polymer to the total solid content of the lower layer slurry and the upper layer slurry may be 2 weight % to 20 weight % or 5 weight % to 15 weight %.

[0157] In this specification, the first binder polymer and the second binder polymer simply refer to the binder polymer contained in the lower layer slurry and the binder polymer contained in the upper layer slurry, respectively, and do not imply any particular order.

[0158] In one embodiment of the present invention, the binder polymer is a component that aids in binding the electrode active material particles to the conductive material and the like and to the electrode current collector, and is added, for example, in an amount of 1 to 50 wt % based on the total weight of the mixture including the electrode active material. Examples of such binder polymers include polyvinylidene fluoride-co-hexafluoropropylene (PVdF), polyvinylidene fluoride-co-trichloroethylene, polymethylmethacrylate, polybutylacrylate, polyacrylonitrile, polyvinylpyrrolidone, polyvinylacetate, ethylene-vinyl acetate copolymer (polyethylene-co-vinyl acetate), polyethylene oxide, polyarylate, cellulose acetate, cellulose acetate butyrate, and cellulose acetate propionate. Any binder polymer selected from the group consisting of methyl propionate, cyanoethyl pullulan, cyanoethyl polyvinyl alcohol, cyanoethyl cellulose, cyanoethyl sucrose, pullulan, and carboxyl methyl cellulose, or a mixture of two or more thereof, can be used, but is not limited to these.

[0159] In one embodiment of the present invention, the negative electrode is fabricated by coating negative electrode active material particles on a negative electrode current collector and drying the coating. If necessary, components such as a conductive material, a binder, and a solvent may be further included.

[0160] In addition, in one embodiment of the present invention, within the scope of the above description, the negative electrode active material used in the negative electrode may be any active material known in the art, without limitation, and within the scope of the above description, the method for manufacturing the negative electrode may be any method known in the art, without limitation.

[0161] In one embodiment of the present invention, the positive electrode may include a positive electrode current collector; and a positive electrode active material layer located on at least one surface of the positive electrode current collector and including a positive electrode active material, a binder polymer, and a conductive material.

[0162] In one embodiment of the present invention, the positive electrode current collector has a thickness of, for example, 3 to 500 μm. Such a positive electrode current collector is not particularly limited as long as it does not cause chemical changes in the battery and is conductive. For example, stainless steel, aluminum, nickel, titanium, baked carbon, or aluminum or stainless steel whose surface has been surface-treated with carbon, nickel, titanium, silver, or the like can be used. The electrode current collector can have fine irregularities on its surface to increase the adhesive strength of the positive electrode active material, and can be in various forms such as a film, sheet, foil, net, porous material, foam, or nonwoven fabric.

[0163] In one embodiment of the present invention, the positive electrode active material is a layered compound such as lithium cobalt oxide (LiCoO2), lithium nickel oxide (LiNiO2), or a compound substituted with one or more transition metals; 1+x Mn 2-x Lithium manganese oxides such as LiMnO4 (where x is 0 to 0.33), LiMnO3, LiMn2O3, and LiMnO2; lithium copper oxide (Li2CuO2); vanadium oxides such as LiV3O8, LiFe3O4, V2O5, and Cu2V2O7; and the chemical formula LiNi 1-x Mx O2 (where M = Co, Mn, Al, Cu, Fe, Mg, B or Ga, and x = 0.01 to 0.3); 2-x M x The lithium intercalation material may be a lithium manganese composite oxide represented by LiMnO2 (where M=Co, Ni, Fe, Cr, Zn, or Ta, and x=0.01 to 0.1) or Li2Mn3MO8 (where M=Fe, Co, Ni, Cu, or Zn); LiMn2O4 in which part of the lithium in the chemical formula is substituted with an alkaline earth metal ion; disulfide compounds; Fe2(MoO4)3, or a composite oxide formed by a combination thereof, and the like, but is not limited to these.

[0164] In one embodiment of the present invention, the conductive material is added in an amount of 1 wt % to 50 wt % based on the total weight of the mixture including the positive electrode active material. The conductive material is not particularly limited as long as it does not cause chemical changes in the battery and has high conductivity. Examples of the conductive material include graphite such as natural graphite and artificial graphite; carbon black such as carbon black, acetylene black, ketjen black, channel black, furnace black, lamp black, and thermal black; conductive fibers such as carbon fiber and metal fiber; metal powders such as carbon fluoride, aluminum, and nickel powder; conductive whiskers such as zinc oxide and potassium titanate; conductive oxides such as titanium oxide; and conductive materials such as polyphenylene derivatives.

[0165] In one embodiment of the present invention, the positive electrode is fabricated by coating positive electrode active material particles on a positive electrode current collector and drying the coated positive electrode active material particles. If necessary, the positive electrode may further include components such as a conductive material, a binder, and a solvent.

[0166] In addition, in the present invention, the positive electrode active material used in manufacturing the positive electrode may be any active material known in the art, and the method for manufacturing the positive electrode may be any method known in the art, without limitation.

[0167] In one embodiment of the present invention, non-limiting examples of solvents used in the manufacture of the negative electrode or anode, i.e., electrode, include acetone, tetrahydrofuran, methylene chloride, chloroform, dimethylformamide, N-methyl-2-pyrrolidone (NMP), cyclohexane, water, or a mixture thereof, etc. These solvents provide an appropriate level of viscosity so that a desired level of slurry coating layer is formed on the surface of the electrode current collector.

[0168] In one embodiment of the present invention, the separator includes a porous polymer substrate and an organic / inorganic composite porous coating layer formed on at least one side of the polymer substrate, and the organic / inorganic composite porous coating layer may include a particulate binder resin and inorganic particles.

[0169] The material used for the separation membrane may be any material commonly used in the art.

[0170] Furthermore, the description of the manufacturing apparatus for an electrode assembly according to the present invention and the configuration of the manufacturing apparatus can also be applied to the manufacturing method according to the present invention and the electrode assembly manufactured by the manufacturing method according to the present invention.

[0171] Although the embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and it will be obvious to those skilled in the art that various modifications and variations are possible within the scope that does not deviate from the technical idea of the present invention described in the claims.

Claims

1. An apparatus for manufacturing an electrode assembly in which first electrodes and second electrodes are alternately arranged between folded separators, comprising: a first electrode supply unit that supplies the first electrode to the stack table; a second electrode supply unit that supplies the second electrode to the stack table; a separation membrane supply unit that supplies the separation membrane to the stack table; a stack table on which the first electrodes, the separators, and the second electrodes are stacked in the form of a stack in which the separators to be last stacked on the stack table have an extended region for being wound in contact with one or more sides of the stack, and the first electrodes and the second electrodes are alternately arranged between the folded separators; a separation membrane winding portion that winds the separation membrane so that the extended region to be wound contacts one or more surfaces of the laminate; and A brushing unit for brushing the wound laminate while heating it. An apparatus for manufacturing an electrode assembly, comprising:

2. The electrode assembly manufacturing apparatus according to claim 1 , wherein the brushing unit includes a brushing body that directly contacts the wound laminate and a brushing heating unit that heats the wound laminate.

3. 3. The apparatus for manufacturing an electrode assembly according to claim 2, wherein the brushing body is provided in the form of a rotating roller or a brush having bristles planted on one surface thereof.

4. The apparatus for manufacturing an electrode assembly according to claim 1 , wherein the brushing unit brushes the entire surface of the extended region of the separator.

5. 10. The apparatus for manufacturing an electrode assembly according to claim 1, further comprising a temperature control unit that heats and brushes the wound laminate at a temperature of 100° C. to 150° C. for 2 to 10 seconds.

6. a press section for heating and pressing the brushed laminate; and a gripper that grips the brushed laminate and moves it to the press section; The electrode assembly manufacturing apparatus according to claim 1 , further comprising:

7. The electrode assembly manufacturing apparatus according to claim 6 , wherein the press unit includes a pair of pressure blocks each including a heater.

8. The separation membrane winding portion is a clamp for gripping an end of the extended region of the separator; a clamping movement unit that pulls the extended region of the gripped separation membrane in a direction opposite to the folded position of the separation membrane; and a rotating section that rotates the stack held by the clamp by pulling the extended region in a direction opposite to the folded position of the separator; The electrode assembly manufacturing apparatus according to claim 1 , comprising:

9. A method for manufacturing an electrode assembly in which first and second electrodes are alternately arranged between folded separators, comprising: providing the first electrode to a stack table; providing the second electrode to the stack table; supplying the separation membrane to the stack table; the separator film to be last stacked on the stack table has an extended region for being wound in contact with one or more sides of the stack, and the first electrodes and the second electrodes are alternately arranged between the folded separator films, thereby manufacturing the stack including the first electrodes, the separator film, and the second electrodes; winding the separator so that the extended region to be wound contacts one or more surfaces of the laminate; and brushing the wound laminate while heating it; A method for manufacturing an electrode assembly, comprising:

10. 10. The method of claim 9, wherein the step of brushing the wound laminate while heating it is performed at a temperature of 100 to 150° C. for 2 to 10 seconds.

11. The method for manufacturing an electrode assembly according to claim 9 , further comprising a heat pressing step of heating and pressing the brushed laminate.

12. The heat pressing step of heating and pressing the brushed laminate includes: gripping the brushed laminate with a gripper and moving it between a pair of pressure blocks each including a heater; removing the gripper from the stack; After the gripper is released, the pair of pressure blocks move toward each other to apply surface pressure to the laminate; and The heater heats the laminate. The method for manufacturing an electrode assembly according to claim 11 , comprising:

13. The step of brushing the wound laminate while heating includes: The method for manufacturing an electrode assembly according to claim 9, wherein the method is performed only in the region of the laminate where winding has been performed.

14. The step of winding the separator so that the extended region to be wound contacts one or more surfaces of the laminate includes: gripping an end of the extended region of the last laminated separator; pulling the extended region of the gripped separator in a direction opposite to the folded position of the separator; and The extended region is pulled in a direction opposite to the folded position of the separator, thereby rotating the gripped stack. A method for manufacturing the electrode assembly according to claim 9 , comprising:

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