Secondary battery manufacturing equipment and method for manufacturing secondary battery using same

Abstract

According to example embodiments, secondary battery manufacturing equipment is provided. The equipment comprises: an unwinder configured to unwind a current collector sheet from a current collector roll; a first edge slitter configured to cut a first edge portion of the current collector sheet in the transverse direction; a second edge slitter configured to cut a second edge portion of the current collector sheet in the transverse direction; and a die coater configured to apply an electrode slurry onto a first surface of the current collector sheet.

Description

Secondary battery manufacturing equipment, and a method for manufacturing a secondary battery using the same

[0001] The present invention relates to a secondary battery manufacturing facility and a method for manufacturing a secondary battery using the same. The present application claims the benefit of Korean application No. 10-2024-0162656, filed on November 15, 2024, which is incorporated herein by reference in its entirety.

[0002] Unlike primary batteries, secondary batteries can be charged and discharged multiple times. Secondary batteries are widely used as energy sources for various wireless devices such as handsets, laptops, and cordless vacuum cleaners. Recently, as the manufacturing cost per unit capacity of secondary batteries has decreased dramatically due to improved energy density and economies of scale, and as the driving range of BEVs (battery electric vehicles) has increased to a level equivalent to that of fuel vehicles, the primary use of secondary batteries is shifting from mobile devices to mobility.

[0003] Secondary batteries are manufactured through electrode, assembly, and activation processes. Among these, the electrode process is the most critical process for determining the yield and performance of the battery cell. The electrode process may include a coating process, a roll press process, and a slitting process. In the coating process, active materials and insulating materials may be applied to the surface of the current collector. In the roll press process, the electrode may be pressed by rolling rolls. The roll press process can improve the density, performance, and surface quality of the electrode. In the slitting process, the electrode may be cut into multiple electrodes according to the design of the battery cell. The slitting process is an optional process and may be omitted.

[0004] The problem that the technical concept of the present invention aims to solve is to provide a secondary battery manufacturing facility with improved yield and productivity, and a method for manufacturing a secondary battery using the same.

[0005] According to exemplary embodiments of the present invention for solving the above-described problem, a secondary battery manufacturing facility is provided. The facility comprises: an unwinder configured to unwind a current collector sheet from a current collector roll; a first edge slitter configured to cut a first edge portion in the transverse direction of the current collector sheet; a second edge slitter configured to cut a second edge portion in the transverse direction of the current collector sheet; and a die coater configured to apply an electrode slurry on a first surface of the current collector sheet.

[0006] The first and second edge slitters are interposed between the unwinder and the die coater.

[0007] The above equipment further includes a half slitter configured to cut the above current collector sheet.

[0008] The above half slitter is configured to cut the current collector sheet processed by the above die coater.

[0009] The width of the first edge portion in the transverse direction is the same as the width of the second edge portion in the transverse direction.

[0010] The width of the first edge portion in the transverse direction is different from the width of the second edge portion in the transverse direction.

[0011] Each of the first and second edge slitters is configured to move in the lateral direction.

[0012] According to exemplary embodiments, a secondary battery manufacturing facility is provided. The facility comprises: an unwinder configured to unwind a current collector sheet from a current collector roll; an edge slitter configured to cut transverse edge portions of the current collector sheet; and a die coater configured to apply an electrode slurry on a first surface of the current collector sheet, wherein the edge slitter is interposed between the unwinder and the die coater.

[0013] According to exemplary embodiments, a method for manufacturing a secondary battery is provided. The method comprises the steps of: winding a current collector sheet from a current collector roll; cutting an edge portion of the current collector sheet; forming a first active material layer on a first surface of the current collector sheet; and forming a second active material layer on a second surface of the current collector sheet.

[0014] The above method further includes the step of cutting an electrode sheet so as to form first and second electrode sheets, and the electrode sheet comprises the current collector sheet, the first active material layer, and the second active material layer.

[0015] The edge portion of the above current collector sheet is cut before the roll press process that rolls the above current collector sheet and the first and second active material layers.

[0016] According to exemplary embodiments of the present invention, the current collector sheet can be cut to the required specifications using edge slitting in the coating process. Accordingly, the ease of inventory management can be improved, and the increase in manufacturing costs due to long-term inventory and inventory disposal can be prevented. Furthermore, since additional cutting processing is unnecessary when purchasing raw materials, the cost of purchasing raw materials can be reduced.

[0017] The effects obtainable from the exemplary embodiments of the present invention are not limited to those mentioned above, and other unmentioned effects can be clearly derived and understood by those skilled in the art to which the exemplary embodiments of the present disclosure belong from the following description. That is, unintended effects resulting from the implementation of the exemplary embodiments of the present disclosure can also be derived by those skilled in the art from the exemplary embodiments of the present disclosure.

[0018] FIG. 1 shows a secondary battery manufacturing facility according to exemplary embodiments.

[0019] FIG. 2 is a flowchart illustrating a method for manufacturing a secondary battery according to exemplary embodiments.

[0020] FIGS. 3 to 7 are plan views illustrating a method for manufacturing a secondary battery according to exemplary embodiments.

[0021] FIG. 8 is a plan view illustrating a method for manufacturing a secondary battery according to exemplary embodiments.

[0022] FIG. 9 is a plan view illustrating a method for manufacturing a secondary battery according to exemplary embodiments.

[0023] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings. Prior to this, terms and words used in this specification and claims should not be interpreted as being limited to their ordinary or dictionary meanings. Instead, based on the principle that the inventor can appropriately define the concepts of terms to best describe his invention, they should be interpreted in a meaning and concept consistent with the technical spirit of the present invention.

[0024] Therefore, the embodiments described in this specification and the configurations illustrated in the drawings are merely the most preferred embodiments of the present invention and do not represent all of the technical ideas of the present invention; thus, it should be understood that various equivalents and modifications that can replace them may exist at the time of filing this application.

[0025] In addition, in describing the present invention, if it is determined that a detailed description of related known components or functions may obscure the essence of the invention, such detailed description is omitted.

[0026] Since embodiments of the present invention are provided to more fully explain the invention to those skilled in the art, the shapes and sizes of the components in the drawings may be exaggerated, omitted, or schematically depicted for clearer explanation. Accordingly, the size or proportion of each component does not entirely reflect the actual size or proportion.

[0027]

[0028] (1st embodiment)

[0029] FIG. 1 shows a secondary battery manufacturing facility according to exemplary embodiments.

[0030] FIG. 2 is a flowchart illustrating a method for manufacturing a secondary battery according to exemplary embodiments.

[0031] FIGS. 3 to 7 are plan views illustrating a method for manufacturing a secondary battery according to exemplary embodiments.

[0032] Referring to FIG. 1, a secondary battery manufacturing facility (100) may include an unwinder (111), first and second rewinders (113a, 113b), a plurality of guide rolls (115), first and second edge slitters (121, 123), a first die coater (131), a second die coater (133), a first drying device (141), a second drying device (143), and a half slitter (150).

[0033] Referring to FIGS. 1 to 3, in P110, a current collector sheet (CS) can be unwound from a whole roll (CR). According to exemplary embodiments, an unwinder (111) can be configured to unwound a current collector sheet (CS) from a current collector roll (CR).

[0034] The direction of movement of the current collector sheet (CS), current collector sheet (CS'), and electrode sheet (ES) is referred to as the Machine Direction (MD). The Machine Direction (MD) may also be referred to as the longitudinal direction of the current collector sheet (CS), current collector sheet (CS'), and electrode sheet (ES). The direction perpendicular to the Machine Direction (MD) is defined as the Transverse Direction (TD) of the current collector sheet (CS), current collector sheet (CS'), and electrode sheet (ES). The Transverse Direction (TD) may also be referred to as the width direction of the current collector sheet (CS), current collector sheet (CS'), and electrode sheet (ES).

[0035] The thickness of the current collector sheet (CS) may be in the range of about 3 μm to about 500 μm. The current collector sheet (CS) may not cause chemical changes in the secondary battery finally manufactured and may have high conductivity. The surface of the current collector sheet (CS) may include a micro-irregular structure to increase the adhesion of the active material. The shape of the current collector sheet (CS) may include any one of a film, sheet, foil, net, porous material, foam, and nonwoven fabric.

[0036] According to exemplary embodiments, a current collector sheet (CS) may be used in the manufacture of an anode, and the current collector sheet (CS) may comprise any one of stainless steel, aluminum, nickel, titanium, calcined carbon, and aluminum-cadmium alloy, but is not limited thereto.

[0037] According to other exemplary embodiments, the current collector sheet (CS) may be used in the manufacture of a cathode, and the current collector sheet (CS) may comprise any one of copper, stainless steel, aluminum, nickel, titanium, calcined carbon, and aluminum-cadmium alloy.

[0038] In the manufacture of secondary batteries, the width of the current collector sheet (CS) in the transverse direction (TD) required may vary depending on the specifications of the final product manufactured. In this example, the width of the current collector sheet (CS) may be the sum of the specification width (T) of the product being produced and the excess width (α).

[0039]

[0040] Next, referring to FIGS. 1 through 4, the edge portions of the current collector sheet (CS) can be cut at P120. The first and second edge slitters (121, 123) may be configured to cut the edge portions in the transverse direction (TD) of the current collector sheet (CS). The first and second edge slitters (121, 123) may be configured to cut the edge portions in the transverse direction (TD) of the current collector sheet (CS). By cutting the edge portions of the current collector sheet (CS), a current collector sheet (CS') having a width in the transverse direction (TD) smaller than that of the current collector sheet (CS) may be provided. The width in the transverse direction (TD) of the current collector sheet (CS') may be substantially the same as the standard width (T).

[0041] According to exemplary embodiments, transverse edge portions of a current collector sheet (CS) may be removed by first and second edge slitters (121, 123). The portion of the current collector sheet (CS) removed by the first edge slitter (121) may be referred to as the first edge portion. The portion of the current collector sheet (CS) removed by the second edge slitter (123) may be referred to as the second edge portion.

[0042] The width of the edge portion of the current collector sheet (CS) removed by the first edge slitter (121) may be substantially the same as the width of the edge portion of the current collector sheet (CS) removed by the second edge slitter (123). The width of the edge portion of the current collector sheet (CS) removed by the first edge slitter (121) may be substantially the same as α / 2, which is half of the excess width (α). The width of the edge portion of the current collector sheet (CS) removed by the second edge slitter (123) may be substantially the same as α / 2, which is half of the excess width (α).

[0043] In reality, it is difficult to accurately match the purchase quantity of current collector rolls (CR) with a standard width (T) with the production quantity of the secondary battery manufacturing process using the current collector rolls (CR). One means to solve this problem is to provide additional slitting during the manufacturing process of the electrode sheet using a rewinding stage, but in this case, quality assurance for the current collector rolls (CR) is impossible. Consequently, electrode rolls (CR) with a width different from the changed standard width (T) are stored in the warehouse as inventory, causing unnecessary production and storage costs.

[0044] According to exemplary embodiments, in a secondary battery manufacturing facility (100) that performs a coating process, by cutting the edge portion of the current collector sheet (CS) during the coating process on the current collector sheet (CS), no additional process is required, and even if the standard width (T) is changed, the manufacturing process of the secondary battery can be performed using the previously purchased current collector roll (CR). Accordingly, the current collector roll (CR) can be introduced into production freely from the standard width (T), thereby reducing human and material resources required for the purchasing process and inventory management of the current collector roll (CR), reducing or minimizing long-term inventory, and enabling cost reduction due to the reduction in the amount of waste of the current collector roll (CR).

[0045] For more flexible inventory management, the first and second edge slitters (121, 123) can be configured to move in the lateral direction (TD). Accordingly, even in the event of frequent changes in the standard width (T), the lateral (TD) position of the first and second edge slitters (121, 123) can be adjusted in response to changes in the standard width (T).

[0046] According to exemplary embodiments, the first and second edge slitters (121, 123) may be interposed between the first die coater (131) and the unwinder (111). According to exemplary embodiments, the first and second edge slitters (121, 123) may be interposed between the first and second die coaters (131, 133) and the unwinder (111).

[0047] According to exemplary embodiments, by performing an edge slitting process before performing a substantial process on the current collector sheet (CS), contamination of the portion cut from the current collector sheet (CS) can be prevented, and the portion of the cut current collector sheet (CS) can be collected and resold.

[0048]

[0049] Next, referring to FIGS. 1, 2 and 5, first active material layers (AL1) can be formed on a first surface (CS1) of a current collector sheet (CS') in P130. Each of the first active material layers (AL1) can extend in the direction of travel (MD). The first active material layers (AL1) can be spaced apart from each other in the transverse direction (TD).

[0050] Forming the first active material layers (AL1) may include applying an electrode slurry to a first surface (CS1) of a current collector sheet (CS') and drying the electrode slurry. A first die coater (131) may be configured to apply the electrode slurry to a first surface (CS1) of a current collector sheet (CS'). A first drying device (141) may be configured to dry the electrode slurry on the first surface (CS1), and accordingly, the first active material layers (AL1) may be provided.

[0051] The electrode slurry may include an electrode active material, a conductive material, a binder, and a solvent. The electrode slurry may be prepared by dissolving the electrode active material, the conductive material, and others in a solvent. The solvent may disperse the components of the electrode slurry, such as the electrode active material. The solvent may be an aqueous solvent or a non-aqueous solvent. The solvent may include any one of DMSO, isopropyl alcohol, NMP, acetone, water, and mixtures thereof.

[0052] According to exemplary embodiments, the electrode active material may be a positive active material, but is not limited thereto. The positive active material is a material capable of causing an electrochemical reaction. The positive active material may be a lithium transition metal oxide. The positive active material may be a layered compound such as lithium cobalt oxide (LiCoO2) and lithium nickel oxide (LiNiO2) substituted with one or more transition metals; lithium manganese oxide substituted with one or more transition metals; or a material with the chemical formula LiNi 1-y M y Lithium nickel-based oxide represented by O2 (where M is any one of Co, Mn, Al, Cu, Fe, Mg, B, Cr, Zn, and Ga, and 0.01≤y≤0.7); Li 1+z Ni 1 / 3 Co 1 / 3 Mn 1 / 3 O2 and Li 1+zN i 0.4 Mn 0.4 Co0.2 Li like O2 1+z Ni b Mn c Co 1-(b+c+d) M d O (2-e) A e It may include a lithium nickel cobalt manganese composite oxide represented by (where -0.5≤z≤0.5, 0.1≤b≤0.8, 0.1≤c≤0.8, 0≤d≤0.2, 0≤e≤0.2, b+c+d<1, M is any one of Al, Mg, Cr, Ti, Si, and Y, and A is any one of F, P, and Cl). The cathode active material is a lithium nickel cobalt manganese composite oxide with the chemical formula Li 1+x M 1-y M' y PO 4-z X z It may include an olivine-based lithium metal phosphate represented as (wherein M is a transition metal, more specifically one of Fe, Mn, Co and Ni, M' is one of Al, Mg and Ti, X is one of F, S and N, -0.5≤x≤+0.5, 0≤y≤0.5, and 0≤z≤0.1).

[0053] In addition, the electrode active material may be a negative electrode active material. The negative electrode active material may include carbon, for example, non-graphitizable carbon, graphite-based carbon, etc. The negative electrode active material is, for example, Li x Fe2O3(0≤x≤1), LixWO2(0≤x≤1), Sn x Me 1-x Me y O z(wherein Me is any one of Mn, Fe, Pb, and Ge, and Me' is any one of Al, B, P, Si, Group 1, Group 2, and Group 3 elements of the periodic table, and halogens; 0 <x≤1 이고; 1≤y≤3 이며; 1≤z≤8) 등의 금속 복합 산화물을 포함할 수 있다. 음극 활물질은, 예컨대, 리튬 금속; 리튬 합금; 규소계 합금; 및 주석계 합금 중 어느 하나를 포함할 수 있다. 음극 활물질은, 예컨대, SnO, SnO2, PbO, PbO2, Pb2O3, Pb3O4, Sb2O3, Sb2O4, Sb2O5, GeO, GeO2, Bi2O3, Bi2O4및 Bi2O5등의 금속 산화물을 포함할 수 있다. 음극 활물질은, 예컨대, 폴리아세틸렌 등의 도전성 고분자 및 Li-Co-Ni 계 재료 등을 포함할 수도 있다.

[0054] The conductive material can possess conductivity without causing chemical changes in the secondary battery ultimately manufactured. The conductive material may include, for example, graphite such as natural graphite or artificial graphite; carbon black such as acetylene black, ketjen black, channel black, furnace black, lamp black, and thermal black; conductive fibers such as carbon fibers or metal fibers; metal powders such as carbon fluoride, aluminum, and nickel powder; conductive whiskey such as zinc oxide and potassium titanate; conductive metal oxides such as titanium oxide and polyphenylene derivatives.

[0055] The binder can improve the adhesion between active materials and the adhesion between the current collector sheet (SS) and the active materials. The binder may include polyvinylidene fluoride (PVDF), polyvinyl alcohol, carboxymethylcellulose (CMC), starch, hydroxypropylcellulose, regenerated cellulose, polyvinylpyrrolidone, tetrafluoroethylene, polyethylene, polypropylene, ethylene-propylene-diene terpolymer (EPDM), sulfonated EPDM, styrene-butylene rubber, and fluororubber, etc.

[0056] The first drying device (141) may include, for example, an oven. The moisture content of the electrode sheet (ES) may be limited to a set numerical range by the first drying device (141). The first drying device (141) may operate, for example, based on dew point-based feedback, but is not limited thereto.

[0057] In FIG. 5, two first active material layers (AL1) are formed by a coating process by a first die coater (131) and a drying process by a first drying device (141), but this is for illustrative purposes only and does not limit the technical concept of the invention in any sense. A person skilled in the art will be able to easily arrive at an embodiment in which one or more than three first active material layers (AL1) are formed by the first die coater (131) based on what is described herein.

[0058]

[0059] Next, referring to FIGS. 1, 2, 5 and 6, second active material layers (AL2) can be formed on a second surface (CS2) of a current collector sheet (CS') in P140. The second surface (CS2) may be opposite to the first surface (CS1). By forming the second active material layers (AL2), an electrode sheet (ES) comprising a current collector sheet (CS'), first active material layers (AL1) and second active material layers (AL2) may be provided. Each of the second active material layers (AL2) may extend in the direction of travel (MD). The second active material layers (AL2) may be spaced apart from each other in the transverse direction (TD).

[0060] The number of second active material layers (AL2) may be substantially the same as the first active material layers (AL1). Accordingly, if one or more first active material layers (AL1) are provided on the first surface (CS1), the same number of second active material layers (AL2) may be formed on the second surface (CS2).

[0061] Forming the second active material layers (AL2) may include applying an electrode slurry to the second surface (CS2) of the current collector sheet (CS') and drying the electrode slurry. The second die coater (133) may be configured to apply the electrode slurry to the second surface (CS2) of the current collector sheet (CS'). The second drying device (143) may be configured to dry the electrode slurry on the second surface (CS2), thereby providing the second active material layers (AL2). Since the second die coater (133) is similar to the first die coater (131) and the second drying device (143) is similar to the first drying device (141), a redundant description thereof is omitted.

[0062]

[0063] Next, referring to FIGS. 1, 2, 5 and 7, an electrode sheet (ES) can be cut at P150. The electrode sheet (ES) can be cut by a half slitter (150). In this example, only the current collector sheet (CS') is separated by the half slitter (150), but depending on the number of first and second active material layers (AL1, AL2), the first and second active material layers (AL1, AL2) may also be separated by the half slitter (150) together with the current collector sheet (CS'). First and second electrode sheets (ESa, ESb) can be formed by cutting the electrode sheet (ES). The half slitter (150) can be configured to separate the electrode sheet (ES) into first and second electrode sheets (ESa, ESb). Each of the first and second electrode sheets (ESa, ESb) may include a current collector sheet (CS) and a first active material layer (AL1) and a second active material layer (AL2).

[0064] A half slitter (150) may be interposed between the second die coater (133) and the first and second rewinders (113a, 113b). The half slitter (150) may be interposed between the first and second die coaters (131, 133) and the first and second rewinders (113a, 113b). The half slitter (150) may be configured to cut the electrode sheet (ES) processed on the first and second die coaters (131, 133).

[0065]

[0066] Subsequently, in P160, a first electrode sheet (ESa) can be wound onto a first electrode roll (ERa), and a second electrode sheet (ESb) can be wound onto a second electrode roll (ERb). The first electrode sheet (ESa) can be wound onto the first electrode roll (ERa) by a first rewinder (113a). The first rewinder (113a) can be configured to wind the first electrode sheet (ESa) onto the first electrode roll (ERa). The second electrode sheet (ESb) can be wound onto the second electrode roll (ERb) by a second rewinder (113b). The second rewinder (113b) can be configured to wind the second electrode sheet (ESb) onto the second electrode roll (ERb).

[0067] In a secondary battery manufacturing facility (100), a current collector roll (CR) is fed and the first and second electrode rolls (ERa, ERb) are completed, so the processing by the secondary battery manufacturing facility (100) can be referred to as roll-to-roll processing.

[0068] A plurality of guide rolls (115) may be configured to adjust, align, prevent shaking of the current collector sheet (CS), current collector sheet (CS'), electrode sheet (ES), and electrode sheets (ESa, ESb) and maintain their tension.

[0069]

[0070] After performing a coating process including P110 to P160, a roll press process, a slitting process, and a notching process may be performed. In the roll press process, the first and second electrode rolls (ERa, ERb) may be loaded into an unwinder of a roll press facility, and the first and second electrode sheets (ESa, ESb) unwound from the first and second electrode rolls (ERa, ERb) may be rolled by a pair of rolls facing each other. Due to the roll press process, the bonding force between the surface of the current collector sheet and the active material may be strengthened. Accordingly, the movement of lithium ions within the electrode may be promoted, and the output and performance of the secondary battery finally manufactured may be improved.

[0071] That is, the edge portion of the current collector sheet (CS) in P120 can be cut before the roll press process. In contrast, if edge slitting is performed after rolling, a wire breakage defect may occur due to a thickness difference between the retained portion and the unretained portion. Here, the retained portion is the portion of the first and second electrode sheets (ESa, ESb) having the first and second active material layers (AL1, AL2). The unretained portion is the portion of the first and second electrode sheets (ESa, ESb) where the current collector sheet (CS) is exposed.

[0072] The slitting process is a process of separating the first and second electrode sheets (ESa, ESb) into a plurality of electrode sheets having a smaller width in the transverse direction. A plurality of tabs may be formed on each of the plurality of electrode sheets by the notching process.

[0073]

[0074] (3rd Example: Method)

[0075] FIG. 8 is a plan view illustrating a method for manufacturing a secondary battery according to exemplary embodiments.

[0076] Referring to FIGS. 3 and FIGS. 8, unlike in FIG. 4, the transverse (TD) widths of the edge portions of the current collector sheet (CS, FIG. 3) removed by each of the first and second edge slitters (121, 123) may differ from each other. The transverse (TD) width of the edge portion of the current collector sheet (CS, FIG. 3) removed by the first edge slitter (121) may be greater than α / 2, which is half of the excess width (α), by a deviation (). The transverse (TD) width of the edge portion of the current collector sheet (CS, FIG. 3) cut by the second edge slitter (123) may be smaller than α / 2, which is half of the excess width (α), by a deviation (). The sum of the transverse (TD) widths of the edge portions of the current collector sheet (CS, see FIG. 3) cut by the first and second edge slitters (121, 123) may be substantially equal to the excess width (α). Accordingly, the transverse (TD) width of the current collector sheet (CS') may be substantially equal to the standard width (T).

[0077]

[0078] (Fourth Example: Method)

[0079] FIG. 9 is a plan view illustrating a method for manufacturing a secondary battery according to exemplary embodiments.

[0080] Unlike in FIGS. 4 and 8, where the current collector sheet (CS, see FIG. 3) is cut by two edge slitters (121, 123), in this example, the current collector sheet (CS, see FIG. 3) may be cut by a single edge slitter (120). The width of the edge portion of the current collector sheet (CS, see FIG. 3) removed by the edge slitter (121) may be equal to the excess width (α). Accordingly, the width in the transverse direction (TD) of the current collector sheet (CS') may be substantially equal to the standard width (T). According to the example of FIG. 9, the secondary battery manufacturing facility may include a single edge slitter (120) instead of the first and second edge slitters (121, 123).

[0081]

[0082] The present invention has been described in more detail above through drawings and embodiments. However, the configurations described in the drawings or embodiments described in this specification are merely one embodiment of the present invention and do not represent all technical concepts of the present invention; therefore, it should be understood that various equivalents and modifications that can replace them may exist at the time of filing this application.

Claims

1. An unwinder configured to unwind a current collector sheet from a current collector roll; A first edge slitter configured to cut a first edge portion in the transverse direction of the above-mentioned total sheet; A second edge slitter configured to cut the second edge portion in the transverse direction of the above-mentioned current collector sheet; and A secondary battery manufacturing facility comprising a die coater configured to apply an electrode slurry onto a first surface of the above-mentioned current collector sheet.

2. In Paragraph 1, A secondary battery manufacturing apparatus characterized in that the first and second edge slitters are interposed between the unwinder and the die coater.

3. In Paragraph 1, A secondary battery manufacturing facility further comprising a half slitter configured to cut the above-mentioned current collector sheet.

4. In Paragraph 3, A secondary battery manufacturing apparatus characterized by the above-described half slitter being configured to cut the above-described current collector sheet processed by the above-described die coater.

5. In Paragraph 1, A secondary battery manufacturing apparatus characterized in that the width in the transverse direction of the first edge portion is the same as the width in the transverse direction of the second edge portion.

6. In Paragraph 1, A secondary battery manufacturing apparatus characterized in that the width in the transverse direction of the first edge portion is different from the width in the transverse direction of the second edge portion.

7. In Paragraph 1, A secondary battery manufacturing apparatus characterized in that each of the first and second edge slitters is configured to move in the lateral direction.

8. An unwinder configured to unwind a current collector sheet from a current collector roll; An edge slitter configured to cut the transverse edge portions of the above-mentioned current collector sheet; and It includes a die coater configured to apply an electrode slurry onto the first surface of the above-mentioned current collector sheet, and A secondary battery manufacturing apparatus characterized by the above edge slitter being interposed between the above unwinder and the above die coater.

9. Step of unwinding the entire sheet from the entire roll; A step of cutting the edge portion of the entire sheet above; A step of forming a first active material layer on a first surface of the above-mentioned current collector sheet; and A method for manufacturing a secondary battery comprising the step of forming a second active material layer on a second surface of the above-mentioned current collector sheet.

10. In Paragraph 9, The method further includes the step of cutting the electrode sheet so that the first and second electrode sheets are formed, and A method for manufacturing a secondary battery characterized in that the electrode sheet comprises the current collector sheet, the first active material layer, and the second active material layer.

11. In Paragraph 10, A method for manufacturing a secondary battery, characterized in that the edge portion of the current collector sheet is cut prior to the roll press process of rolling the current collector sheet and the first and second active material layers.

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