Method for manufacturing an electrode assembly with improved workability and an electrode assembly manufactured using the same

Abstract

A method for manufacturing an electrode assembly according to an embodiment of the present invention includes a step of unwinding a positive electrode sheet, a separator sheet, and a negative electrode sheet from a plurality of roll members, a step of forming a laminate while the unwound positive electrode sheet, the separator sheet, and the negative electrode sheet pass between a pair of guide rolls, and a step of punching the laminate including the positive electrode sheet, the separator sheet, and the negative electrode sheet. Each of the positive electrode sheet and the negative electrode sheet has an active material and a non-conductive material alternately applied with respect to the traveling direction of the guide roll, and the step of punching the laminate punches a portion where the non-conductive material is applied.

Description

Technical Field

[0001] [Cross - reference to Related Applications] This application claims the benefit of priority based on Korean Patent Application No. 10 - 2022 - 0135189, filed on October 19, 2022, and all the contents disclosed in the document of the Korean Patent Application are incorporated herein by reference.

[0002] The present invention relates to an electrode assembly and an electrode assembly manufactured using the same, and more specifically, to a method for manufacturing an electrode assembly with improved processability and safety and an electrode assembly manufactured using the same.

Background Art

[0003] With the development of technology and the increasing demand for mobile devices, the demand for secondary batteries as an energy source has been rapidly increasing. In particular, secondary batteries have attracted much attention not only as an energy source for mobile devices such as mobile phones, digital cameras, notebook computers, and wearable devices, but also for power devices such as electric bicycles, electric vehicles, and hybrid electric vehicles.

[0004] Research on using lithium secondary batteries with high energy density and discharge voltage has been actively carried out and is in a stage of partial commercialization.

[0005] Such lithium secondary batteries are manufactured by coating and drying a positive electrode active material or a negative electrode active material, a binder, and a conductive material in the form of a slurry on a current collector to form an electrode mixture layer to manufacture a positive electrode and a negative electrode, interposing a separator between the positive electrode and the negative electrode, and incorporating the laminated electrode assembly together with an electrolytic solution into a battery case.

[0006] As an advanced structured electrode assembly in such a hybrid form of jelly roll type and stack type, a full cell with a positive electrode / separator / negative electrode structure of a certain unit size, or a bi-cell with a positive electrode (negative electrode) / separator / negative electrode (positive electrode) / separator / positive electrode (negative electrode) structure, is folded using a long continuous separator film to develop a stack / folding type electrode assembly.

[0007] In addition, in order to improve the processability of the conventional stack type electrode assembly and meet the demands for various forms of battery cells, a lamination / stack type electrode assembly with a structure in which unit cells in which an electrode and a separator are alternately laminated and joined (laminated) are stacked has also been developed.

[0008] When manufacturing a stack type electrode assembly, it is common to manufacture the positive electrode, separator, and negative electrode in separate processes, and then laminate them and join them by simultaneously applying heat and pressure in a lamination method. At this time, before joining the electrode and the separator by the lamination method, a punching process for realizing the form of the electrode assembly can be carried out. The punching process can manufacture a stack type electrode assembly by laminating the positive electrode and the negative electrode individually punched and then laminating them together with the separator by the lamination method.

[0009] However, if the stack type electrode assembly is manufactured while laminating after individually punching the electrodes in this way, there is a problem that the assembly process time becomes long and the cost increases.

[0010] In addition, in the electrode assembly, the separator may shrink due to heat to prevent a short circuit phenomenon due to contact between the positive electrode and the negative electrode, or in the punching process, the separator may be cut larger than the negative electrode and the positive electrode and then laminated. However, in this way, since a larger amount of separator than necessary is cut, the production unit price becomes high.

Summary of the Invention

Problems to be Solved by the Invention

[0011] The problem to be solved by the present invention is to provide a method for manufacturing an electrode assembly that reduces the complexity of the punching and lamination processes and improves processability, and an electrode assembly manufactured using the same.

[0012] Another object of the present invention is to provide a method for manufacturing an electrode assembly that can prevent the occurrence of the cause of the short-circuit phenomenon during the punching process and improve the product quality, and an electrode assembly manufactured using the same.

[0013] Furthermore, an object of the present invention is to provide a method for manufacturing an electrode assembly that accurately sets the punching position during the process and increases the production yield, and an electrode assembly manufactured using the same.

[0014] The problems to be solved by the present invention are not limited to the above-described problems, and problems not mentioned will be clearly understood by those having ordinary knowledge in the technical field to which the present invention pertains from the present specification and the attached drawings.

Means for Solving the Problems

[0015] A method for manufacturing an electrode assembly according to an embodiment of the present invention includes a step of unwinding a positive electrode sheet, a separator sheet, and a negative electrode sheet from a plurality of roll members, respectively; a step of forming a laminate while the unwound positive electrode sheet, the separator sheet, and the negative electrode sheet pass between a pair of guide rolls; and a step of punching the laminate including the positive electrode sheet, the separator sheet, and the negative electrode sheet, wherein in each of the positive electrode sheet and the negative electrode sheet, an active material and a non-conductive material are alternately coated with reference to the running direction of the guide roll, and the step of punching the laminate punches a portion where the non-conductive material is coated.

[0016] The step of punching the laminate can punch the positive electrode sheet, the separator sheet, and the negative electrode sheet simultaneously.

[0017] The negative electrode sheet is formed to contain lithium metal.

[0018] A marker portion for guiding the punching position of the laminate is formed at a portion where the non-conductive material is applied.

[0019] The marker portion is formed on the same line as the line where the non-conductive material is applied in the process of applying the non-conductive material.

[0020] The non-conductive material can contain a polymer material.

[0021] As the polymer material, a polyethylene (PE) - based material can be used.

[0022] The step of alternately applying the active material and the non-conductive material to each of the positive electrode sheet and the negative electrode sheet is performed before the step of unwinding the positive electrode sheet and the negative electrode sheet from the roll member.

[0023] The step of passing the laminate through the guide roll to form the laminate is performed immediately after the step of unwinding the positive electrode sheet, the separator sheet, and the negative electrode sheet from the plurality of roll members, respectively.

[0024] In the step of punching the laminate, a cutting member can be used, and the non-conductive material is formed of a material having ductility so that the electrode material does not adhere to the cutting member.

[0025] The cutting member can directly cut the positive electrode sheet, the separator sheet, and the negative electrode sheet.

[0026] The direction of punching the laminate may be perpendicular to the running direction of the guide roll.

[0027] An electrode assembly according to another embodiment of the present invention is an electrode assembly manufactured by the method for manufacturing an electrode assembly described above, including a positive electrode, a separator, and a negative electrode formed after punching the laminate, wherein the positive electrode and the negative electrode each include an active material layer and non-conductive layers located on both sides of the active material layer.

[0028] Based on the running direction of the guide roll, the widths of the positive electrode, the separator, and the negative electrode may be the same as each other.

[0029] Based on the running direction of the guide roll, the widths of the positive electrode active material layer and the negative electrode active material layer included in the positive electrode and the negative electrode may be the same as each other.

Advantages of the Invention

[0030] According to the embodiment, after simultaneously unwinding the positive electrode sheet / separator / negative electrode sheet and then simultaneously punching them, the complexity of the punching and lamination processes can be reduced.

[0031] Also, by forming non-conductive layers at both ends of the positive electrode / negative electrode, the short-circuit phenomenon at the side surface can be prevented.

[0032] Furthermore, it is possible to prevent the cutting member from directly contacting the electrode material during the punching process and contaminating the electrode with electrode materials having different polarities attached to the cutting member.

[0033] Also, by forming a marker portion in the non-conductive layer, the punching position can be accurately set during the process, and the production yield can be increased.

[0034] The effects of the present invention are not limited to the effects described above, and the effects not mentioned will be clearly understood by those having ordinary knowledge in the technical field to which the present invention pertains from the present specification and the attached drawings.

Brief Description of the Drawings

[0035]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Mode for Carrying Out the Invention

[0036] Hereinafter, with reference to the accompanying drawings, various embodiments of the present invention will be described in detail so that those having ordinary knowledge in the technical field to which the present invention pertains can easily implement them. The present invention can be realized in various different forms and is not limited to the embodiments described herein.

[0037] For the sake of clarity in explaining the present invention, parts that are unnecessary for the explanation are omitted, and the same reference numerals are assigned to the same or similar components throughout the specification.

[0038] Also, the sizes and thicknesses of the respective components shown in the drawings are arbitrarily shown for the convenience of explanation, and the present invention is not necessarily limited to what is shown in the drawings. The thicknesses are enlarged in the drawings to clearly represent various layers and regions. And, in the drawings, for the convenience of explanation, the thicknesses of some layers and regions are exaggeratedly shown.

[0039] Furthermore, throughout the specification, when a certain part "includes" a certain component, this means that other components can be further included, rather than excluding other components, unless otherwise stated to the contrary.

[0040] Also, throughout the specification, when it is stated as "on a plane", this means when looking at the target part from above, and when it is stated as "in a cross-section", this means when looking at the cross-section obtained by vertically cutting the target part from the side.

[0041] FIG. 1 is a diagram showing a manufacturing apparatus for an electrode assembly according to an embodiment of the present invention. FIG. 2 is a diagram for explaining a manufacturing method of the electrode assembly of the present invention. FIG. 3 is a diagram for explaining a process of punching a laminate according to an embodiment of the present invention. FIG. 4 is a cross-sectional view taken along the cutting line A-A' of FIG. 3.

[0042] Referring to FIG. 1, the manufacturing apparatus for an electrode assembly according to this embodiment includes a plurality of roll members 100, 200, 300, a transfer member (not shown) that conveys sheets 110, 210, 310 unwound from the plurality of roll members 100, 200, 300 respectively, a pair of guide rolls 400 that guide the plurality of sheets 110, 210, 310, and a cutting member 500 that punches the plurality of sheets 110, 210, 310.

[0043] The plurality of roll members 100, 200, 300 include a first winding roll 100 that winds the positive electrode sheet 110, a second winding roll 200 that winds the separator sheet 210, and a third winding roll 300 that winds the negative electrode sheet 310. At this time, the positive electrode sheet 110 is in an unpunched state, and as will be described later, it may be wound around the first winding roll 100 in the form of a sheet that extends long in one direction with a positive electrode active material layer and a non-conductive layer formed on the positive electrode current collector. The separator sheet 210 may also be wound around the second winding roll 200 in an unpunched state. The negative electrode sheet 310 is also in an unpunched state, and as will be described later, it may be wound around the third winding roll 300 in the form of a sheet that extends long in one direction with a negative electrode active material layer and a non-conductive layer formed on the negative electrode current collector.

[0044] The transfer member may be a conveyor belt unit and can serve to convey the sheets 110, 210, 310 in one direction (x-axis direction).

[0045] The guide roll 400 includes an upper guide roll 410 and a lower guide roll 420 that are vertically spaced apart, and the sheets 110, 210, and 310 can pass between them.

[0046] The cutting member 500 may be a punching knife that directly cuts the positive electrode sheet 110, the separator sheet 210, and the negative electrode sheet 310. The cutting member 500 can cut the sheets 110, 210, and 310 in a direction perpendicular to the first direction (x-axis direction) in which the sheets 110, 210, and 310 are transferred.

[0047] Hereinafter, a method for manufacturing an electrode assembly using the manufacturing apparatus for an electrode assembly according to this embodiment will be described.

[0048] The positive electrode sheet 110, the separator sheet 210, and the negative electrode sheet 310 are respectively unwound from the plurality of roll members 100, 200, and 300 and transferred along the first direction (x-axis direction), and the positive electrode sheet 110, the separator sheet 210, and the negative electrode sheet 310 can be in close contact with each other in a direction perpendicular to the transfer direction (x-axis direction) while being unwound. In other words, the sheets 110, 210, and 310 are unwound from the plurality of roll members 100, 200, and 300 so as to be in a stacked state.

[0049] The unwound positive electrode sheet 110, separator sheet 210, and negative electrode sheet 310 can form a laminate while passing between a pair of guide rolls 400. The sheets 110, 210, and 310 in the form of a laminate can pass between the upper guide roll 410 and the lower guide roll 420 that are vertically spaced apart. The step of passing through the guide roll 400 to form the laminate is preferably performed immediately after the step of unwinding the positive electrode sheet 110, the separator sheet 210, and the negative electrode sheet 310 from the plurality of roll members 100, 200, and 300, respectively.

[0050] The laminate formed by passing between a pair of guide rolls 420 can still maintain the form of a continuous sheet. Also, the sheets 110, 210, 310 unwound so as to be laminated can form a closer laminate while passing between the pair of guide rolls 420. Thereafter, the sheets 110, 210, 310 can be maintained in a laminated state while being transferred in the first direction (x-axis direction). Thereafter, a lamination process may be performed in which heat and pressure are applied so that the positive electrode sheet 110, the separator sheet 210, and the negative electrode sheet 310 are joined to each other.

[0051] Figure 2 schematically shows the portion punched by the cutting member 500 after a plurality of sheets 110, 210, 310 have passed between a pair of guide rolls 400.

[0052] Referring to FIGS. 1 and 2, the laminate including the positive electrode sheet 110, the separator sheet 210, and the negative electrode sheet 310 can be punched using the cutting member 500. At this time, the cutting member 500 can directly cut the positive electrode sheet 110, the separator sheet 210, and the negative electrode sheet 310.

[0053] The positive electrode sheet 110 can have a holding portion where the active material layer 111 is formed along a direction (y-axis direction) perpendicular to the traveling direction of the guide roll 400, and a plain portion 112 where the active material is not coated. The holding portion and the plain portion 112 are sequentially arranged in the -y axis direction. The active material layer 111 may be a positive electrode mixture layer including a positive electrode active material, a binder, and a conductive material. As an example, the active material layer 111 can be formed by coating and drying a positive electrode active material, a binder, and a conductive material on a current collector in the form of a slurry.

[0054] The negative electrode sheet 310 can have a holding portion where the active material layer 311 is formed along a direction (y-axis direction) perpendicular to the traveling direction of the guide roll 400, and a plain portion 312 where the active material is not coated. The holding portion and the plain portion 312 are arranged in sequence in the y-axis direction. The active material layer 311 may be a negative electrode mixture layer containing a negative electrode active material, a binder, and a conductive material. As an example, the active material layer 311 can be formed by coating and drying a negative electrode active material, a binder, and a conductive material on a current collector in the form of a slurry.

[0055] In other words, the plain portions 112 and 312 formed on the positive electrode sheet 110 and the negative electrode sheet 310 respectively are arranged in different directions with respect to the holding portion as a reference. At this time, the tab-shaped protrusions formed on the positive electrode sheet 110 and the negative electrode sheet 310 respectively are arranged in different directions with respect to the holding portion as a reference. Here, the tab-shaped protrusion is used as an electrode tab. In other words, the plain portions 112 and 312 may be used as electrode tabs as they are, and as another example, the tab-shaped protrusion may be shaped such that another electrode tab can be easily attached.

[0056] FIG. 3 shows a state where the positive electrode sheet 110, the separator sheet 210, and the negative electrode sheet 310 that overlap each other in the vertical direction (z-axis direction in FIG. 1) are separated planar-ly when viewed along the z-axis direction during the process of punching out the laminate.

[0057] Referring to FIG. 3, when punching the laminate, each of the positive electrode sheet 110 and the negative electrode sheet 310 may be in a state where the active material and the non-conductive material are alternately coated with reference to the running direction (x-axis direction) of the guide roll 400. The step of alternately coating the active material and the non-conductive material on each of the positive electrode sheet 110 and the negative electrode sheet 310 is performed before the positive electrode sheet 110 and the negative electrode sheet 310 are unwound from the roll members 100 and 300. The step of punching the laminate can punch the positive electrode sheet 110, the separator sheet 210, and the negative electrode sheet 310 simultaneously. The punching direction of the laminate may be a direction perpendicular to the running direction of the guide roll 400 (z-axis direction in FIG. 1).

[0058] In this embodiment, since the positive electrode sheet 110, the separator sheet 210, and the negative electrode sheet 310 are punched simultaneously, it is possible to solve the problem that in the conventional method, after individually punching the electrode and the separator and then manufacturing the stacked electrode assembly while laminating, the assembly process time becomes long and the cost increases.

[0059] Thus, if the sheets 110, 210, 310 are punched simultaneously, the cutting member 500 may be contaminated with the electrode material. The laminate is punched at regular intervals while the sheets 110, 210, 310 are running. If the laminate is cut with the electrode material adhering to the cutting member 500, the electrode material may come into contact with the electrode sheet having a polarity different from that of the electrode material adhering to the cutting member 500. In such a case, the quality of the electrode may deteriorate, and ultimately, the problem of a decrease in the battery life may occur.

[0060] According to this embodiment, when punching the laminate, the electrode portion coated with the non-conductive material is punched. As shown in FIG. 3, along the punching position line 610 crossing the non-conductive layers 113, 313, the cutting member 500 in FIG. 2 can cut the laminate.

[0061] A marker portion 600 for guiding the punching position of the laminate is formed on the portion where the non-conductive material is applied. The marker portion 600 is formed on the same line as the line where the non-conductive material is applied during the process of applying the non-conductive material. In other words, as shown in FIG. 3, it is preferable that the marker portion 600 is formed substantially on the same line as the punching position line 610.

[0062] As an example, when applying the active material and the non-conductive material, the coating device for the non-conductive material and the marker portion forming device are interlocked to leave a marker at the central position of the portion where the non-conductive material is applied, thereby forming the marker portion 600.

[0063] By forming the marker portion 600, the punching position of the cutting member 500 can be found more accurately during the automated process, and thus an improvement effect on the production yield can be expected. The marker portion 600 according to the present embodiment not only serves to accurately find the punching position, but also can play a role in alignment when the positive electrode sheet 110, the separator sheet 210, and the negative electrode sheet 310 are unwound from a plurality of roll members 100, 200, 300.

[0064] Referring to FIG. 4, in the positive electrode sheet 110, an active material layer 111 and a non-conductive layer 113 are formed on at least one surface of the positive electrode current collector 115, and in the negative electrode sheet 310, an active material layer 311 and a non-conductive layer 313 are formed on at least one surface of the negative electrode current collector 315. As described above, along the punching position line 610, by cutting the laminate in the vertical direction (z-axis direction) by the cutting member 500 in FIG. 2, the non-conductive layer 113 of the positive electrode sheet 110, the separator sheet 210, and the non-conductive layer 313 of the negative electrode sheet 310 are simultaneously punched. The left and right widths of the cutting member 500 can correspond to the interval between adjacent punching position lines 610.

[0065] The non-conductive material for forming the non-conductive layer 313 according to this embodiment preferably includes a polymer material. As an example, a polyethylene (PE) - based polymer material can be used, but it is not limited thereto, and any polymer material with high ductility can be used. The non-conductive material according to this embodiment preferably has greater ductility than ceramics and greater ductility than general metal materials. The non-conductive material can also have ductility similar to that of the more ductile lithium metal.

[0066] According to this embodiment, the negative electrode sheet 310 is preferably formed of lithium metal. In a lithium-ion battery, carbon-based materials, silicon, lithium metal, etc. are used as negative electrode active materials. Among them, lithium metal has the advantage of being able to obtain the highest energy density. If a lithium metal battery is used in this way, due to the high reactivity of lithium metal and the volume expansion at the negative electrode during charge and discharge of the battery, and the surface non-uniformity phenomenon that occurs during the process of lithium metal electrodeposition and stripping on the negative electrode, a stable interface cannot be formed between the electrolyte and the lithium metal electrode, and a continuous electrolyte decomposition reaction may occur. Such an electrolyte side reaction can shorten the battery life while rapidly increasing the battery resistance.

[0067] To reduce the above problems, when using a lithium metal battery, it is necessary to constantly apply a strong pressure to the battery cell. To apply such pressure, a spring or a strong pressure adhesive can be used. That is, if a strong pressure is not applied during charge and discharge, the battery life will decrease. Therefore, a strong pressure is applied to the battery cell when using a lithium metal battery. According to this embodiment, since the non-conductive layers 113 and 313 are formed using a highly ductile polymer material, the non-conductive layers 113 and 313 do not crack even under strong pressure conditions and do not damage the current collectors 115 and 315. If the non-conductive layers 113 and 313 were formed of a material with low ductility such as ceramics, they might crack under strong pressure conditions.

[0068] FIG. 5 is a diagram showing a unit cell formed after punching out the laminate of FIG. 4. FIG. 6 is a diagram showing a method of manufacturing a conventional electrode assembly.

[0069] Referring to FIG. 5, the unit cell 700 according to this embodiment is formed by the method of manufacturing the electrode assembly described above. The unit cell 700 includes a positive electrode 118, a separator 218, and a negative electrode 318 formed after punching out the laminate. At this time, the positive electrode 118 and the negative electrode 318 each include an active material layer 111, 311 and non-conductive layers 113, 313 located on both sides of the active material layers 111, 311.

[0070] According to this embodiment, based on the traveling direction (x-axis direction) of the guide roll 400 in FIG. 1, the widths of the positive electrode 118, the separator 218, and the negative electrode 318 are substantially the same as each other. This is because the positive electrode sheet, the separator, and the negative electrode sheet are simultaneously punched out in the method of manufacturing the electrode assembly according to this embodiment. At this time, the traveling direction (x-axis direction) of the guide roll 400 is perpendicular to the direction (y-axis direction) in which the electrode tab 116 in FIG. 5 protrudes, and the widths of the positive electrode 118, the separator 218, and the negative electrode 318 may be substantially the same as each other based on the direction in which the electrode tab 116 protrudes.

[0071] Moreover, according to this embodiment, based on the traveling direction (x-axis direction) of the guide roll 400 in FIG. 1, the widths of the positive electrode active material layer 111 and the negative electrode active material layer 311 included in the positive electrode 118 and the negative electrode 318 may be the same as each other. Referring to FIG. 6, in the conventional case where the positive electrode 11 and the negative electrode 31 are individually punched out and then laminated, it was for preventing a short-circuit phenomenon due to contact between the positive electrode and the negative electrode, or in the punching process, the separator 21 was cut larger than the negative electrode 31 and the positive electrode 11. However, in this embodiment, even if the widths of the positive electrode active material layer 111 and the negative electrode active material layer 311 corresponding substantially to the widths of the electrodes are made the same, since the non-conductive layers 113, 313 are formed, the short-circuit phenomenon can be prevented.

[0072] In this embodiment, if the laminate is punched, there may occur a phenomenon in which at least one of the plurality of sheets is pushed. However, by covering the portions where the non-conductive layers 113 and 313 can contact the positive electrode 118 and the negative electrode 318, a short-circuit phenomenon can be prevented.

[0073] Referring to FIG. 1 again, the unit cell 700 of FIG. 5 formed after simultaneously punching the positive electrode sheet 110, the separator sheet 210, and the negative electrode sheet 310 in the state of the laminate can be transported and laminated in a pick & place manner to form an electrode assembly. As another example, the unit cell 700 formed by punching in the state of the laminate is loaded and stored in a loading box such as a magazine. Thereafter, the unit cell 700 stored in the loading box can be transported and laminated again in a pick & place manner to form an electrode assembly.

[0074] Thereafter, a battery cell can be manufactured by incorporating an electrode assembly including at least one unit cell 700 together with an electrolytic solution into a battery case.

[0075] As described above, for convenience of explanation, it has been described that the three layers of the positive electrode / separator / negative electrode are unwound and worked simultaneously. However, when forming the laminate, electrodes with different polarities from each other must be separated by the separator and mutually insulated. Therefore, one end of the basic unit for forming the laminate is finished with the separator. As an example, a four-layer structure of positive electrode / separator / negative electrode / separator may be used as the basic unit, or a six-layer structure of positive electrode / separator / negative electrode / separator / positive electrode / separator or negative electrode / separator / positive electrode / separator / negative electrode / separator may be used as the basic unit, and more layers can also be used as the basic unit for simultaneous operation.

[0076] Specifically, when using a four-layer structure of positive electrode / separator / negative electrode / separator as the basic unit, a winding roll that winds the separator sheet below the third winding roll 300 in FIG. 1 is arranged, and it is unwound together with the positive electrode sheet 110, the separator sheet 210, and the negative electrode sheet 310. When forming the laminate according to the above-described embodiment, one end of the basic unit can be the separator.

[0077] As described above, the preferred embodiments of the present invention have been described in detail. However, the scope of the rights of the present invention is not limited thereto, and various modifications and improvements by those skilled in the art using the basic concept of the present invention defined in the following claims also belong to the scope of the rights of the present invention.

Explanation of Reference Numerals

[0078] 100, 200, 300: Winding rolls 110: Positive electrode sheet 111, 311: Active material layer 112, 312: Plain part 113, 313: Non-conductive layer 115, 315: Current collector 118: Positive electrode 210: Separator sheet 218: Separator 310: Negative electrode sheet 318: Negative electrode 400: Guide roll 500: Cutting member 600: Marker part 610: Punching position line

Claims

1. a step in which a positive electrode sheet, a separator sheet, and a negative electrode sheet are each unwound from a plurality of roll members; a step of forming a laminate while the unwound positive electrode sheet, the separator sheet, and the negative electrode sheet pass between a pair of guide rolls; a step of punching the laminate including the positive electrode sheet, the separator sheet, and the negative electrode sheet; and in each of the positive electrode sheet and the negative electrode sheet, an active material and a non-conductive material are alternately applied with reference to the traveling direction of the guide roll; The method for manufacturing an electrode assembly, wherein the step of punching the laminate punches a portion where the non-conductive material is applied.

2. The method for manufacturing an electrode assembly according to claim 1, wherein the step of punching the laminate punches the positive electrode sheet, the separator sheet, and the negative electrode sheet simultaneously.

3. The method for manufacturing an electrode assembly according to claim 1, wherein the negative electrode sheet is formed to contain lithium metal.

4. The method for manufacturing an electrode assembly according to any one of claims 1 to 3, wherein a marker portion for guiding a punching position of the laminate is formed in a portion where the non-conductive material is applied.

5. The method for manufacturing an electrode assembly according to claim 4, wherein the marker portion is formed on the same line as a line where the non-conductive material is applied in the process of applying the non-conductive material.

6. The method for manufacturing an electrode assembly according to any one of claims 1 to 3, wherein the non-conductive material contains a polymer material.

7. The method for manufacturing an electrode assembly according to claim 6, wherein the polymer material uses a polyethylene (PE) system.

8. The method for manufacturing an electrode assembly according to any one of claims 1 to 3, wherein the step of alternately applying the active material and the non-conductive material to each of the positive electrode sheet and the negative electrode sheet is performed before the positive electrode sheet and the negative electrode sheet are unwound from the roll member.

9. The method for manufacturing an electrode assembly according to any one of claims 1 to 3, wherein the step of passing through the guide roll to form the laminate is performed immediately after the step in which the positive electrode sheet, the separator sheet, and the negative electrode sheet are each unwound from the plurality of roll members.

10. The step of punching out the laminate uses a cutting member, and the non-conductive material is formed of a ductile material so that the electrode material does not adhere to the cutting member. The method for manufacturing an electrode assembly according to any one of claims 1 to 3.

11. The method for manufacturing an electrode assembly according to claim 10, wherein the cutting member directly cuts the positive electrode sheet, the separator, and the negative electrode sheet.

12. The method for manufacturing an electrode assembly according to claim 10, wherein the direction of punching out the laminate is perpendicular to the running direction of the guide roll.

13. The positive electrode, the separator, and the negative electrode are laminated in a preset direction. Each of the positive electrode and the negative electrode includes an active material layer and non-conductive layers located on both sides of the active material layer. The non-conductive layer is an electrode assembly containing a polymer material.

14. Based on a direction perpendicular to the preset direction and perpendicular to the direction in which the electrode tab of the positive electrode or the negative electrode protrudes, the widths of the positive electrode, the separator, and the negative electrode are the same as each other. The electrode assembly according to claim 13.

15. Based on a direction perpendicular to the direction in which the electrode tab protrudes, the widths of the positive electrode active material layer and the negative electrode active material layer included in the positive electrode and the negative electrode are the same as each other. The electrode assembly according to claim 14.

Images