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

Abstract

According to embodiments, secondary battery manufacturing equipment is provided. The equipment comprises: a die coater configured to apply an electrode slurry on a current collector sheet so that an electrode slurry lane is formed on the current collector sheet; and a magnetic module configured to apply a magnetic field to an electrode sheet including the current collector sheet and the electrode slurry lane, wherein the magnetic field has a non-uniform intensity in the transverse direction of the electrode sheet.

Description

Secondary battery manufacturing equipment and method for manufacturing secondary batteries 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. This application claims the benefit of Korean Application No. 10-2024-0116174, filed August 28, 2024, which is incorporated herein by reference in its entirety.

[0002] Unlike primary batteries, secondary batteries can be charged and discharged multiple times. They are widely used as a power source for various wireless devices, including handsets, laptops, and cordless vacuum cleaners. Recently, improved energy density and economies of scale have dramatically reduced the per-unit manufacturing cost of secondary batteries. Furthermore, as the range of battery electric vehicles (BEVs) has increased to match that of fuel-powered vehicles, the primary use of secondary batteries is shifting from mobile devices to mobility.

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

[0004] The technical idea of ​​the present invention aims to solve a problem by providing a secondary battery manufacturing facility with improved reliability 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 includes a die coater configured to apply electrode slurry onto a current collector sheet so that electrode slurry lanes are formed on the current collector sheet; and a magnetic module configured to apply a magnetic field to an electrode sheet including the current collector sheet and the electrode slurry lanes, wherein the magnetic field has a non-uniform intensity in a transverse direction of the electrode sheet.

[0006] The magnetic module comprises a magnetic device configured to generate the magnetic field and a magnetic shield configured to partially absorb the magnetic field generated by the magnetic device.

[0007] The above magnetic shield comprises any one of iron, nickel and their alloys.

[0008] The magnetic shield includes holes that overlap with edge portions of the electrode slurry lane.

[0009] The above magnetic shield includes a plurality of holes arranged in the transverse direction.

[0010] The number of the above plurality of holes is 3 or more.

[0011] According to exemplary embodiments, a secondary battery manufacturing facility is provided. The facility includes a die coater configured to apply electrode slurry onto a current collector sheet so as to form electrode slurry lanes on the current collector sheet; and a magnetic module configured to apply a magnetic field to the electrode sheet including the current collector sheet and the electrode slurry lanes, wherein the magnetic module includes a magnetic device configured to generate the magnetic field and a magnetic shield configured to partially absorb the magnetic field generated by the magnetic device.

[0012] The above magnetic field has a non-uniform intensity in the transverse direction of the electrode sheet.

[0013] The above magnetic shield comprises any one of iron, nickel and their alloys.

[0014] The magnetic shield includes holes that overlap with edge portions of the electrode slurry lane.

[0015] The above magnetic shield includes a plurality of holes arranged in the transverse direction of the electrode sheet.

[0016] The number of the above plurality of holes is 3 or more.

[0017] A secondary battery manufacturing facility according to exemplary embodiments of the present invention includes a magnetic module capable of controlling the intensity distribution of a magnetic field for aligning active materials in an electrode slurry. Aligning the active materials can control the resistance distribution of the electrode sheets, thereby providing a battery cell with improved lithium deposition and swelling characteristics.

[0018] The effects that can be obtained from the exemplary embodiments of the present invention are not limited to the effects mentioned above, and other effects not mentioned can be clearly derived and understood by those skilled in the art to which the exemplary embodiments of the present disclosure pertain from the following description. In other words, unintended effects resulting from practicing 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.

[0019] Figure 1 illustrates a secondary battery manufacturing facility according to exemplary embodiments.

[0020] Figure 2 illustrates a magnetic shield by a secondary battery manufacturing facility according to exemplary embodiments.

[0021] FIG. 3 is a flowchart illustrating a method for manufacturing a secondary battery according to exemplary embodiments.

[0022] Figure 4 illustrates a magnetic shield by a secondary battery manufacturing facility according to exemplary embodiments.

[0023] Figure 5 illustrates a magnetic shield by a secondary battery manufacturing facility according to exemplary embodiments.

[0024] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings. Prior to this, it should be noted that the terms and words used in this specification and claims should not be construed as limited to their conventional or dictionary meanings. Based on the principle that the inventor can appropriately define the concepts of terms to best explain his or her invention, they should be interpreted in a way that aligns with the technical spirit of the present invention.

[0025] Accordingly, 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. Therefore, it should be understood that there may be various equivalents and modified examples that can replace them at the time of filing this application.

[0026] In addition, when describing the present invention, if it is determined that a detailed description of a related known configuration or function may obscure the gist of the present invention, the detailed description is omitted.

[0027] Since the embodiments of the present invention are provided to more fully explain the present invention to those skilled in the art, the shapes and sizes of components in the drawings may be exaggerated, omitted, or schematically illustrated for clearer explanation. Accordingly, the sizes and proportions of each component do not fully reflect the actual sizes or proportions.

[0028]

[0029] (Example 1)

[0030] FIG. 1 illustrates a secondary battery manufacturing facility (1000) according to exemplary embodiments.

[0031] Figure 2 illustrates processing of electrode sheets by a secondary battery manufacturing facility (1000) according to exemplary embodiments.

[0032] Referring to FIGS. 1 and 2, the secondary battery manufacturing facility (1000) may include an unwinder (1011), a rewinder (1013), a die coater (1020), a magnetic module (1030), a drying device (1040), guide rolls (1050), a die coater (1060), a magnetic module (1070), and a drying device (1080).

[0033] A current collector roll (CR) may be loaded into an unwinder (1011). The unwinder (1011) may be configured to unwind a current collector sheet (CS) from the current collector roll (CR). An electrode sheet (ES) may be provided as the current collector sheet (CS) is processed by a die coater (1020), a magnetic module (1030), a drying device (1040), a die coater (1060), a magnetic module (1070), and a drying device (1080). A rewinder (1013) may be configured to wind the electrode sheet (ES) onto an electrode roll (ER). The electrode sheet (ES) may be wound onto the electrode roll (ER). After a predetermined winding amount target is reached, the electrode roll (ER) may be cut and separated from the electrode sheet (ES). Accordingly, the current collector sheet (CS) and the electrode sheet (ES) can be moved between the unwinder (1011) and the rewinder (1013), and the processing by the secondary battery manufacturing equipment (1000) can be referred to as roll-to-roll processing.

[0034] The moving direction of the current collector sheet (CS) and the 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) and the electrode sheet (ES). The direction perpendicular to the machine direction (MD) is defined as the transverse direction (TD) of the current collector sheet (CS) and the electrode sheet (ES). The transverse direction (TD) may also be referred to as the width direction of the current collector sheet (CS) and the electrode sheet (ES). The vertical direction (VD) may be substantially perpendicular to each of the machine direction (MD) and the transverse direction (TD).

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

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

[0037] For example, a current collector sheet (CS) can be used in the manufacture of a negative electrode, and the current collector sheet (CS) can include any one of copper, stainless steel, aluminum, nickel, titanium, calcined carbon, and aluminum-cadmium alloy.

[0038] The die coater (1020) may be configured to apply electrode slurry to a current collector sheet (CS) to form an electrode slurry lane (SL). A portion of the electrode sheet (ES) covered by the electrode slurry lane (SL) may be referred to as a holding portion. The holding portion may extend in the traveling direction (MD).

[0039] An electrode slurry lane (SL) 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, the binder, and the like in a solvent. The solvent may disperse the electrode active material and the like. 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. The amount of solvent used may be determined based on the target viscosity of the slurry. Parameters determining the amount of solvent used include the coating thickness of the slurry, the manufacturing yield, and the workability.

[0040] According to exemplary embodiments, the electrode active material may be, but is not limited to, a cathode active material. The cathode active material is a material capable of causing an electrochemical reaction. The cathode active material may be a lithium transition metal oxide. The cathode active material may have the chemical formula Li. 1+x M 1-y M' y PO 4-z X z (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) and may include, but is not limited to, an olivine-based lithium metal phosphate.

[0041] The cathode active material is 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; chemical formula LiNi 1-y M y Lithium nickel oxide expressed as O2 (wherein, 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 Co 0.2 Li like O2 1+z Ni b Mn c Co 1-(b+c+d) M d O (2-e) A e (wherein, -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).

[0042] Additionally, the electrode active material may be a negative electrode active material. The negative electrode active material may include carbon, such as non-graphitizable carbon, graphitic carbon, etc. The negative electrode active material may include, 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, elements of group 1, 2 and 3 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.

[0043] The conductive material can be conductive without causing a chemical change in the secondary battery being 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 summer black; conductive fibers such as carbon fiber or metal fiber; metal powders such as fluorocarbon, aluminum, and nickel powder; conductive whiskey such as zinc oxide or potassium titanate; conductive metal oxides such as titanium oxide, and polyphenylene derivatives.

[0044] The binder can enhance the bonding between the active material and the conductive material and the bonding strength to the current collector sheet (CS). The binder may include polyvinylidene fluoride (PVDF), polyvinyl alcohol, CMC, starch, hydroxypropyl cellulose, regenerated cellulose, polyvinylpyrrolidone, tetrafluoroethylene, polyethylene, polypropylene, EPDM, sulfonated EPDM, styrene butylene rubber, fluoroelastomer, and various copolymers.

[0045] The solvent may be an aqueous solvent or a non-aqueous solvent. The solvent may include any one of dimethyl sulfoxide (DMSO), isopropyl alcohol, N-methylpyrrolidone (NMP), acetone, water, and mixtures thereof.

[0046] The magnetic module (1030) may be positioned downstream of the die coater (1020). The magnetic module (1030) may be configured to process a portion of the electrode sheet (ES) processed by the die coater (1020). The die coater (1020) may be interposed between the magnetic module (1030) and the unwinder (1011).

[0047] The magnetic module (1030) may include a magnetic device (1031) and a magnetic shield (1033). The magnetic module (1030) may be configured to apply a magnetic field to the electrode sheet (ES). According to exemplary embodiments, the magnetic field applied to the electrode sheet (ES) by the magnetic module (1030) may have a non-uniform intensity in the transverse direction (TD). The intensity of the magnetic field applied to the electrode sheet (ES) by the magnetic module (1030) may vary along the transverse direction.

[0048] The magnetic device (1031) may be configured to generate a magnetic field. The magnetic device (1031) may include an electromagnet and / or a permanent magnet. When the magnetic device (1031) includes an electromagnet, the magnetic device (1031) may include a core and a coil. The magnetic field generated by the magnetic device (1031) may be substantially parallel to the vertical direction (VD), but is not limited thereto. The magnetic field may also include a component oblique to the vertical direction (VD). The magnetic device (1031) may be configured to align the active material in the electrode slurry lane (SL).

[0049] The magnetic shield (1033) may be configured to absorb at least a portion of the magnetic field generated by the magnetic device (1031). The magnetic shield (1033) may include holes (1033H). The holes (1033H) of the magnetic shield (1033) may expose a surface of the electrode sheet (ES). According to exemplary embodiments, the holes (1033H) may overlap with edge portions of the electrode sheet (ES) in the vertical direction (VD). According to exemplary embodiments, the holes (1033H) may expose edge portions of the electrode sheet (ES). According to exemplary embodiments, the holes (1033H) may overlap with uncoated portions of the electrode sheet (ES) and edge portions of the electrode slurry lane (SL) in the vertical direction (VD). According to exemplary embodiments, the holes (1033H) may expose the non-conductive portions of the electrode sheet (ES) and the edge portions of the electrode slurry lane (SL). According to exemplary embodiments, each of the holes (1033H) may not overlap the central portion of the electrode sheet (ES) in the transverse direction (TD) and the vertical direction (VD). The central portion of the electrode sheet (ES) in the transverse direction (TD) may be covered by the magnetic shield (1033).

[0050] According to exemplary embodiments, the magnetic shield (1033) may include a material having a high permeability. According to exemplary embodiments, the magnetic shield (1033) may include a metal. The magnetic shield (1033) may include an alloy thereof, such as iron, nickel, and permalloy. The magnetic shield (1033) may be configured to block a magnetic field generated by the magnetic device (1031) or to reduce the strength of a magnetic field applied to the electrode sheet (ES).

[0051] The intensity of the magnetic field applied to the portion of the electrode sheet (ES) that overlaps the holes (1033H) of the magnetic shield (1033) in the vertical direction (VD) may be different from the intensity of the magnetic field applied to the portion of the electrode sheet (ES) that does not overlap the holes (1033H) in the vertical direction (VD) (i.e., covered by the magnetic shield (1033)). The intensity of the magnetic field applied to the portion of the electrode sheet (ES) that overlaps the holes (1033H) of the magnetic shield (1033) in the vertical direction (VD) may be greater than the intensity of the magnetic field applied to the portion of the electrode sheet (ES) that does not overlap the holes (1033H) in the vertical direction (VD) (i.e., covered by the magnetic shield (1033)).

[0052] According to exemplary embodiments, the intensity of the magnetic field applied to the edge portions of the electrode slurry lane (SL) and the uncoated portions of the electrode sheet (ES) may be different from the intensity of the magnetic field applied to the center portion of the electrode slurry lane (SL). According to exemplary embodiments, the intensity of the magnetic field applied to the edge portions of the electrode slurry lane (SL) and the uncoated portions of the electrode sheet (ES) may be greater than the intensity of the magnetic field applied to the center portion of the electrode slurry lane (SL).

[0053] The uncoated portion of the electrode sheet (ES) is used to form the electrode tab. When a battery cell is manufactured using the electrode sheet (ES), electrons generated by the electrochemical reaction of the battery cell move through the electrode tab. Accordingly, the electrochemical reaction of a portion of the electrode close to the electrode tab can proceed faster than the electrochemical reaction of a portion of the electrode far from the electrode tab. According to exemplary embodiments, by increasing the degree of alignment of the active material at the edge portions of the electrode slurry lane (SL), the resistance near the electrode tab can be reduced, and the electrochemical reaction within the electrode can be uniform. Furthermore, lithium precipitation caused by high current density near the electrode tab can be eliminated or mitigated.

[0054] The secondary battery manufacturing facility (1000) may include an additional die coater for providing an insulating slurry on the electrode sheet (ES). By providing the insulating slurry, insulating lanes covering the edge portions of the electrode slurry lane (SL) may be formed. The insulating slurry may include, for example, an insulating material, styrene butadiene rubber (SBR), a binder, a stabilizer, and a solvent. The insulating material may include a ceramic such as boehmite.

[0055] The drying device (1040) may be positioned downstream of the magnetic module (1030). The drying device (1040) may be configured to process a portion of the electrode sheet (ES) processed by the magnetic module (1030). The drying device (1040) may be interposed between the magnetic module (1030) and the rewinder (1013).

[0056] The drying device (1040) may be configured to dry the electrode sheet (ES). The drying device (1040) may be, for example, an oven. The moisture content of the electrode sheet (ES) may be limited to a set numerical range by the drying device (1040). The drying device (1040) may operate based on, for example, dew point-based feedback, but is not limited thereto.

[0057] The first surface of the current collector sheet (CS) can be treated by a die coater (1020), a magnetic module (1030), and a drying device (1040). To treat the second surface of the current collector sheet (CS), the current collector sheet (CS) can be guided by a guide roll (1150) so that the second surface of the current collector sheet (CS) faces upward in a space where the secondary battery manufacturing equipment (1000) is installed.

[0058] The die coater (1060) may be configured to apply electrode slurry to a current collector sheet (CS) to form an electrode slurry lane (SL). Since the die coater (1060) is substantially the same as the die coater (1020), a duplicate description of the die coater (1060) is omitted.

[0059] The magnetic module (1070) may be positioned downstream of the die coater (1020). The magnetic module (1070) may be configured to process a portion of the electrode sheet (ES) processed by the die coater (1020). The die coater (1020) may be interposed between the magnetic module (1070) and the unwinder (1011).

[0060] The magnetic module (1070) may include a magnetic device (1071) and a magnetic shield (1073). The magnetic module (1070) may be substantially identical to the magnetic module (1030). The magnetic device (1071) may be substantially identical to the magnetic device (1071). The magnetic shield (1073) may be substantially identical to the magnetic shield (1073). Accordingly, redundant descriptions of the magnetic module (1070), the magnetic device (1071), and the magnetic shield (1073) are omitted.

[0061] The drying device (1080) may be positioned downstream of the magnetic module (1070). The drying device (1080) may be configured to process a portion of the electrode sheet (ES) processed by the magnetic module (1070). The drying device (1080) may be interposed between the magnetic module (1070) and the rewinder (1013).

[0062] The drying device (1080) may be substantially identical to the drying device (1070). Accordingly, a duplicate description of the drying device (1080) is omitted.

[0063]

[0064] (Example 2: Method)

[0065] FIG. 3 is a flowchart illustrating a method for manufacturing a secondary battery according to exemplary embodiments.

[0066] Referring to FIGS. 1 to 3, an electrode slurry lane (SL) can be formed on a first surface of a current collector sheet (CS) at P110. The electrode slurry lane (SL) can be formed in a die coater (1020).

[0067] Next, at P120, a non-uniform magnetic field can be applied to the electrode slurry lane (SL). The magnetic field can have a non-uniform intensity in the transverse direction (TD). The magnetic field can be applied by a magnetic module (1030). By applying the magnetic field, the electrode slurry lane (SL) can be magnetized. By the magnetization of the electrode slurry lane (SL), the orientation of the crystal plane of the active material (e.g., natural graphite) included in the electrode slurry (SL) can be aligned with respect to the current collector sheet (CS).

[0068] Next, at P130, the electrode slurry lane (SL) can be dried. The electrode slurry lane (SL) can be dried by a drying device (1040).

[0069] Next, an electrode slurry lane (SL) can be formed on the second surface of the current collector sheet (CS) at P140. The electrode slurry lane (SL) can be formed in a die coater (1060).

[0070] Next, at P150, a non-uniform magnetic field can be applied to the electrode slurry lane (SL). The magnetic field can have a non-uniform intensity in the transverse direction (TD). The magnetic field can be applied by a magnetic module (1070). By applying the magnetic field, the electrode slurry lane (SL) can be magnetized. By the magnetization of the electrode slurry lane (SL), the orientation of the crystal plane of the active material (e.g., natural graphite) included in the electrode slurry (SL) can be aligned with respect to the current collector sheet (CS).

[0071] Next, at P160, the electrode slurry lane (SL) can be dried. The electrode slurry lane (SL) can be dried by a drying device (1040).

[0072]

[0073] The processes P110 to P160 may be performed simultaneously, but may be performed on different portions of the electrode sheet (ES). Accordingly, the same portion of the electrode sheet (ES) may undergo the processes P110 to P160 sequentially.

[0074] After performing the coating process including P110 to P160, a roll press process, an additional drying process, a slitting process, and a notching process may be performed. The roll press process may be performed using a roll press facility including pressure rolls. By performing the roll press process, the bonding force between the surface of the electrode plate 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 ultimately manufactured secondary battery may be improved.

[0075] The drying process may include supplying dry air into a drying chamber or supplying thermal energy, such as infrared radiation or high-temperature air, to the electrodes within the chamber. The drying process can improve the uniformity and reliability of the electrodes by removing moisture from the electrodes.

[0076] The slitting process separates an electrode into multiple electrodes with smaller widths in the transverse direction. The electrode can then be cut into a shape including tabs by a notching process.

[0077]

[0078] (Example 3: Equipment)

[0079] FIG. 4 illustrates a magnetic shield (1033') by a secondary battery manufacturing facility according to exemplary embodiments.

[0080] Referring to FIGS. 2 and 4, the magnetic shield (1033') is substantially the same as the magnetic shield (1033), except that it includes a hole (1033H') that is different from the holes (1033H). The hole (1033H') may overlap the center of the transverse direction (TD) of the electrode slurry lane (SL) in the vertical direction (VD). The hole (1033H') may expose the center of the transverse direction (TD) of the electrode slurry lane (SL). The hole (1033H') may not overlap the edge portions of the transverse direction (TD) of the electrode slurry lane (SL) in the vertical direction (VD). The magnetic shield (1033') may cover the edge portions of the transverse direction (TD) of the electrode slurry lane (SL).

[0081] The intensity of the magnetic field applied to a portion of the electrode sheet (ES) that overlaps the hole (1033H') of the magnetic shield (1033') in the vertical direction (VD) may be different from the intensity of the magnetic field applied to a portion of the electrode sheet (ES) that is not overlapped with the hole (1033H') in the vertical direction (VD) (i.e., covered by the magnetic shield (1033')). The intensity of the magnetic field applied to a portion of the electrode sheet (ES) that is overlapped with the hole (1033H') of the magnetic shield (1033') in the vertical direction (VD) may be greater than the intensity of the magnetic field applied to a portion of the electrode sheet (ES) that is not overlapped with the hole (1033H') in the vertical direction (VD) (i.e., covered by the magnetic shield (1033')).

[0082] According to exemplary embodiments, the intensity of the magnetic field applied to the center portion of the electrode slurry lane (SL) in the transverse direction (TD) may be different from the intensity of the magnetic field applied to the edge portions of the electrode slurry lane (SL) in the transverse direction (TD) and the uncoated portions of the electrode sheet (ES). According to exemplary embodiments, the intensity of the magnetic field applied to the center portion of the electrode slurry lane (SL) in the transverse direction (TD) may be greater than the intensity of the magnetic field applied to the edge portions of the electrode slurry lane (SL) in the transverse direction (TD) and the uncoated portions of the electrode sheet (ES).

[0083] According to exemplary embodiments, when a magnetic shield (1033') replaces a magnetic shield (1033), the alignment of the active material in the center of an electrode manufactured using the electrode sheet (ES) may be higher than the alignment of the active material in the edge portions. Accordingly, the current density can be alleviated from being concentrated on the electrode tab, and the current density can be uniformed, thereby alleviating lithium deposition in a battery cell including the electrode.

[0084]

[0085] (Example 4: Equipment)

[0086] Figure 5 illustrates a magnetic shield by a secondary battery manufacturing facility according to exemplary embodiments.

[0087] Referring to FIGS. 2 and 5, the magnetic shield (1033”) is substantially the same as the magnetic shield (1033), except that it includes holes (1033H”) that are different from the holes (1033H). The magnetic shield (1033”) may include a plurality of holes (1033H”) arranged in a transverse direction (TD). The magnetic shield (1033”) may include three or more holes (1033H”).

[0088] The intensity of the magnetic field applied to the portion of the electrode sheet (ES) that overlaps the holes (1033H”) of the magnetic shield (1033”) in the vertical direction (VD) may be different from the intensity of the magnetic field applied to the portion of the electrode sheet (ES) that is not overlapped with the holes (1033H”) in the vertical direction (VD) (i.e., covered by the magnetic shield (1033”). The intensity of the magnetic field applied to the portion of the electrode sheet (ES) that is overlapped with the holes (1033H”) of the magnetic shield (1033”) in the vertical direction (VD) may be greater than the intensity of the magnetic field applied to the portion of the electrode sheet (ES) that is not overlapped with the holes (1033H”) in the vertical direction (VD) (i.e., covered by the magnetic shield (1033”).

[0089] According to exemplary embodiments, by patterning an area of ​​an electrode sheet (ES) to which a relatively strong magnetic field is applied, swelling of an electrode manufactured using the electrode sheet (ES) can be dispersed, and the quality of contact between an electrode slurry lane (SL) and a current collector sheet (CS) can be improved. Accordingly, swelling of a battery cell manufactured using the electrode can be mitigated.

[0090]

[0091] The present invention has been described in more detail through drawings and examples. However, the configurations described in the drawings or examples described in this specification are merely embodiments of the present invention and do not represent all of the technical ideas of the present invention. Therefore, it should be understood that various equivalents and modified examples may exist as of the time of this application.

Claims

1. A die coater configured to apply electrode slurry onto a current collector sheet so that an electrode slurry lane is formed on the current collector sheet; and A magnetic module configured to apply a magnetic field to an electrode sheet including the above-described current collector sheet and the above-described electrode slurry lane, A secondary battery manufacturing facility characterized in that the magnetic field has an uneven intensity in the transverse direction of the electrode sheet.

2. In paragraph 1, A secondary battery manufacturing facility characterized in that the magnetic module includes a magnetic device configured to generate the magnetic field and a magnetic shield configured to partially absorb the magnetic field generated by the magnetic device.

3. In paragraph 2, A secondary battery manufacturing facility, characterized in that the magnetic shield comprises any one of iron, nickel and their alloys.

4. In paragraph 2, A secondary battery manufacturing facility, characterized in that the magnetic shield includes holes overlapping with edge portions of the electrode slurry lane.

5. In paragraph 2, A secondary battery manufacturing facility characterized in that the magnetic shield includes a plurality of holes arranged in the transverse direction.

6. In paragraph 5, A secondary battery manufacturing facility characterized in that the number of the plurality of holes is three or more.

7. A die coater configured to apply electrode slurry onto a current collector sheet so that an electrode slurry lane is formed on the current collector sheet; and A magnetic module configured to apply a magnetic field to an electrode sheet including the above-described current collector sheet and the above-described electrode slurry lane, A secondary battery manufacturing facility characterized in that the magnetic module includes a magnetic device configured to generate the magnetic field and a magnetic shield configured to partially absorb the magnetic field generated by the magnetic device.

8. In paragraph 7, A secondary battery manufacturing facility characterized in that the magnetic field has an uneven intensity in the transverse direction of the electrode sheet.

9. In paragraph 7, A secondary battery manufacturing facility, characterized in that the magnetic shield comprises any one of iron, nickel and their alloys.

10. In paragraph 7, A secondary battery manufacturing facility, characterized in that the magnetic shield includes holes overlapping with edge portions of the electrode slurry lane.

11. In paragraph 7, A secondary battery manufacturing facility, characterized in that the magnetic shielding device includes a plurality of holes arranged in the transverse direction of the electrode sheet.

12. In paragraph 11, A secondary battery manufacturing facility characterized in that the number of the plurality of holes is three or more.

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