Method and apparatus for manufacturing secondary battery

Abstract

The present invention provides a method for manufacturing a secondary battery, the method comprising: a stacking step of stacking a plurality of electrode assemblies by alternately arranging a plurality of first electrodes and a plurality of second electrodes between separators while folding the separators in a zigzag shape by reciprocating the separators left and right; a separator cutting step of cutting the separators to a length appropriate for wrapping the plurality of electrode assemblies to prepare extra separators; a wrapping step of wrapping the electrode assemblies with the extra separators; a thermal compression step of pressing the plurality of electrode assemblies together with a row in a stacking direction to closely attach the plurality of electrode assemblies in the stacking direction; and an electrode assembly cutting step of cutting the separators positioned between the plurality of electrode assemblies to be separated into individual electrode assemblies, wherein the stacking step comprises the steps of: stacking an a-type first electrode having an a-type first electrode tab among the plurality of first electrodes in a region corresponding to the individual electrode assemblies; stacking an a-type second electrode having an a-type second electrode tab among the plurality of second electrodes in a region corresponding to the individual electrode assemblies; stacking a b-type first electrode having a b-type first electrode tab at a different position from the a-type first electrode tab among the plurality of first electrodes in a region corresponding to the individual electrode assemblies; and stacking a b-type second electrode having a b-type second electrode tab at a different position from the a-type second electrode tab among the plurality of second electrodes in a region corresponding to the individual electrode assemblies, wherein the a-type first electrode tab, the a-type second electrode tab, the b-type first electrode tab, and the b-type se

Description

Method for manufacturing a secondary battery and apparatus for manufacturing a secondary battery

[0001] The present invention relates to a method for manufacturing a secondary battery and an apparatus for manufacturing a secondary battery, and more specifically, to a method for manufacturing a secondary battery and an apparatus for manufacturing a secondary battery that increases the productivity of a secondary battery electrode assembly.

[0002] This application claims the benefit of Korean application No. 10-2024-0171151, filed on November 26, 2024, which is incorporated herein by reference in its entirety.

[0003] Generally, chemical batteries are classified into primary batteries, which are used for single discharge, and secondary batteries, which can be reused through repeated charging and discharging. Due to the aforementioned repeated charging and discharging, secondary batteries are being applied in various technological fields across industries.

[0004] As everyone knows, secondary batteries are manufactured by sequentially stacking a positive electrode, a separator, and a negative electrode and immersing them in an electrolyte solution. The methods for manufacturing the internal electrode assembly of a secondary battery are broadly classified into two types.

[0005] In other words, for small secondary batteries, a method of placing the negative and positive plates on a separator and winding them into a jelly-roll form is widely used, while for medium and large secondary batteries with a larger electrical capacity, a method of stacking the negative, positive, and separator in an appropriate order is widely used.

[0006] In addition, there are various methods for manufacturing the internal electrode assembly of a secondary battery in a stacked manner, but among them, the Z-stacking method is formed in a zigzag folded form, and the negative and positive plates are stacked alternately between the zigzag folded separators.

[0007] However, in this conventional Z-stacking method, negative or positive plates are alternately arranged one by one between zigzag-folded separators, which results in inefficiency in terms of the productivity of the secondary battery electrode assembly.

[0008] Accordingly, there is a demand for technology regarding a secondary battery manufacturing method and a secondary battery manufacturing apparatus that increase the productivity of the secondary battery electrode assembly.

[0009] The first technical problem that the present invention aims to solve is to provide a method for manufacturing a secondary battery that increases the productivity of the secondary battery electrode assembly.

[0010] The second technical objective of the present invention is to provide a secondary battery manufacturing apparatus that increases the productivity of a secondary battery electrode assembly.

[0011] To achieve the first technical objective, the present invention comprises: a stacking step of forming a plurality of electrode assemblies by alternately arranging a plurality of first electrodes and a plurality of second electrodes between the separators while folding the separator back and forth in a zigzag shape; a separator cutting step of providing an extra separator by cutting the separator to a length that can wrap the plurality of electrode assemblies; a wrapping step of wrapping the plurality of electrode assemblies with the extra separator; a heat pressing step of pressing the plurality of electrode assemblies in the stacking direction with heat to make the plurality of electrode assemblies adhere in the stacking direction; and an electrode assembly cutting step of cutting the separator located between the plurality of electrode assemblies to separate them into individual electrode assemblies; wherein the stacking step comprises: a step of stacking a type 1 electrode having a type 1 electrode tab among a plurality of first electrodes in an area corresponding to the individual electrode assembly; and a step of stacking a type 2 electrode having a type 2 electrode tab among a plurality of second electrodes in an area corresponding to the individual electrode assembly. A method for manufacturing a secondary battery comprises: a step of stacking a type b first electrode having a type b first electrode tab at a position different from the type a first electrode tab among a plurality of first electrodes in a region corresponding to the individual electrode assembly; and a step of stacking a type b second electrode having a type b second electrode tab at a position different from the type a second electrode tab among a plurality of second electrodes in a region corresponding to the individual electrode assembly; wherein the type a first electrode tab, the type a second electrode tab, the type b first electrode tab, and the type b second electrode tab are spaced apart from each other and do not overlap.

[0012] In some embodiments, the stacking step may include: a base separator placement step in which a separator is placed in a first direction; a plurality of first electrode placement step in which a plurality of first electrodes are placed spaced apart from each other on the base separator; a second direction separator placement step in which a separator connected to the base separator is folded on the base separator on which the spaced-apart first electrodes are placed and is placed in a second direction opposite to the first direction; a plurality of second electrode placement step in which a plurality of second electrodes are placed spaced apart from each other on the second direction separator; and a first direction separator placement step in which a separator connected to the second direction separator is folded on the second direction separator on which the spaced-apart second electrodes are placed and is placed in a first direction opposite to the second direction.

[0013] In some embodiments, the plurality of electrode assemblies may be one of a monocell having different types of electrodes located at both ends and a bicell having the same type of electrodes located at both ends.

[0014] In some embodiments, in the stacking step, the images projected perpendicularly to the xy plane of the first electrode body portions of the plurality of first electrodes and the second electrode body portions of the plurality of second electrodes may be configured to overlap each other.

[0015] In some embodiments, in the stacking step, the plurality of first electrodes and the plurality of second electrodes may be configured such that the tabs provided on each of the plurality of first electrodes and the tabs provided on each of the plurality of second electrodes are respectively disposed on the outer side of the corner portion excluding the folded corner portion of the separator.

[0016] In some embodiments, after the electrode assembly cutting step, the individual electrode assembly may be wrapped by the cut separator.

[0017] In some embodiments, in the stacking step, the type a first electrode and the type b first electrode may be stacked alternately, and the type a second electrode and the type b second electrode may be stacked alternately.

[0018] In some embodiments, in the stacking step, a plurality of type a first electrodes may be stacked after a plurality of type b first electrodes, and a plurality of type a second electrodes may be stacked after a plurality of type a second electrodes.

[0019] The present invention comprises: a stacking step of stacking a separator by moving it back and forth to fold it in a zigzag shape, and alternately arranging a plurality of first electrodes and a plurality of second electrodes between the separators to form a first electrode assembly and a second electrode assembly spaced apart from each other; a separator cutting step of cutting the separator to a length such that it can wrap the first electrode assembly and the second electrode assembly to provide an extra separator; and a wrapping step of wrapping the first electrode assembly and the second electrode assembly with the extra separator. The present invention provides a method for manufacturing a secondary battery, comprising: an electrode assembly cutting step of cutting the separator located between the first electrode assembly and the second electrode assembly to separate them into individual electrode assemblies; wherein, in the stacking step, when the plurality of electrodes are stacked in the first electrode assembly region and the second electrode assembly region, respectively, the electrode tabs in the first electrode assembly region and the electrode tabs in the second electrode assembly region are stacked asymmetrically with respect to the surface where the separator is cut, and the position of the electrode tab provided in the first electrode assembly is positioned outside the first side corner, which is one of the two side corners adjacent to the folded corner of the separator, and the position of the electrode tab provided in the second electrode assembly is positioned outside the second side corner, which is the other of the two side corners adjacent to the folded corner of the separator.

[0020] To achieve the second technical objective, the present invention comprises: a stacking section that stacks a plurality of electrode assemblies by alternately arranging a plurality of first electrodes and a plurality of second electrodes between the separators while reciprocating the separator left and right to fold it in a zigzag shape; a separator cutting section that cuts the separator to a length capable of wrapping the plurality of electrode assemblies to provide an extra separator; and a wrapping section that wraps the plurality of electrode assemblies with the extra separator. The present invention provides a secondary battery manufacturing apparatus comprising: an electrode assembly cutting unit that cuts the separator located between the plurality of electrode assemblies to separate them into individual electrode assemblies; wherein the stacking unit stacks a type a first electrode having a type a first electrode tab among a plurality of first electrodes in an area corresponding to the individual electrode assembly, stacks a type b first electrode having a type b first electrode tab at a different position from the type a first electrode tab among a plurality of first electrodes in an area corresponding to the individual electrode assembly, stacks a type a second electrode having a type a second electrode tab among a plurality of second electrodes in an area corresponding to the individual electrode assembly, and stacks a type b second electrode having a type b second electrode tab at a different position from the type a second electrode tab among a plurality of second electrodes in an area corresponding to the individual electrode assembly, and is configured such that the type a first electrode tab, the type a second electrode tab, the type b first electrode tab, and the type b second electrode tab are spaced apart from each other and do not overlap.

[0021] In some embodiments, the stacking unit may include: a separator table having a zigzag-folded separator size in which a plurality of electrodes can be arranged and accommodated; a separator supply unit that supplies a separator that is folded in a zigzag shape by reciprocating the separator left and right; a first electrode placement unit that arranges a plurality of first electrodes spaced apart from each other between the separators supplied while being folded in a zigzag shape; and a second electrode placement unit that arranges a plurality of second electrodes spaced apart from each other between the separators supplied while being folded in a zigzag shape after the plurality of first electrodes have been arranged.

[0022] In some embodiments, the first electrode placement portion and the second electrode placement portion may be configured to be positioned so that the images projected perpendicularly to the xy plane of the first electrode body portions of the plurality of first electrodes and the second electrode body portions of the plurality of second electrodes can be superimposed on each other.

[0023] In some embodiments, the first electrode placement portion and the second electrode placement portion may be configured to arrange the plurality of first electrodes and the plurality of second electrodes such that the tabs provided on each of the plurality of first electrodes and the tabs provided on each of the plurality of second electrodes are respectively arranged on the outer side of the corner portion excluding the folded corner portion of the separator.

[0024] In some embodiments, after the electrode assembly cutting portion cuts the electrode assembly, the individual electrode assembly may be configured to be wrapped by the cut separator.

[0025] In some embodiments, the stacking portion may be configured to alternately stack the type a first electrode and the type b first electrode, and alternately stack the type a second electrode and the type b second electrode.

[0026] In some embodiments, the stacking portion may be configured such that a plurality of type a first electrodes are stacked, then a plurality of type b first electrodes are stacked, and then a plurality of type a second electrodes are stacked.

[0027] The present invention comprises: a stacking section that folds a separator in a zigzag shape by moving it back and forth left and right, and alternately arranges a plurality of first electrodes and a plurality of second electrodes between the separators to form a first electrode assembly and a second electrode assembly spaced apart from each other; a separator cutting section that cuts the separator to a length such that it can wrap the first electrode assembly and the second electrode assembly to provide an extra separator; and a wrapping section that wraps the first electrode assembly and the second electrode assembly with the extra separator. The present invention provides a secondary battery manufacturing apparatus comprising: an electrode assembly cutting unit that cuts the separator located between the first electrode assembly and the second electrode assembly to separate them into individual electrode assemblies; wherein, when one of the plurality of electrodes is stacked in the first electrode assembly area and the second electrode assembly area, respectively, the electrode tabs in the first electrode assembly area and the electrode tabs in the second electrode assembly area are stacked asymmetrically with respect to the surface where the separator is cut, and the position of the electrode tab provided in the first electrode assembly is positioned outside of the first side corner, which is one of the two side corners adjacent to the folded corner of the separator, and the position of the electrode tab provided in the second electrode assembly is positioned outside of the second side corner, which is the other of the two side corners adjacent to the folded corner of the separator.

[0028] The secondary battery manufacturing method and secondary battery manufacturing apparatus according to the embodiments of the present invention have the effect of increasing the productivity of the secondary battery electrode assembly.

[0029] 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.

[0030] FIG. 1 is a diagram showing the flowchart of a method for manufacturing a secondary battery according to one embodiment of the present invention.

[0031] FIG. 2 is a diagram showing a stacking step among a secondary battery manufacturing method according to one embodiment of the present invention.

[0032] FIG. 3 is a planar drawing showing a stacking step in which first electrodes, a separator, and second electrodes are stacked in a secondary battery manufacturing method according to one embodiment of the present invention.

[0033] FIG. 4 is a drawing showing a stacked portion of a secondary battery manufacturing device according to one embodiment of the present invention.

[0034] FIG. 5 is a drawing showing a secondary battery manufacturing apparatus according to one embodiment of the present invention.

[0035] Hereinafter, preferred embodiments of the concept of the present invention will be described in detail with reference to the accompanying drawings. However, embodiments of the concept of the present invention may be modified in various different forms, and the scope of the concept of the present invention should not be interpreted as being limited by the embodiments described below. It is preferable to interpret the embodiments of the concept of the present invention as being provided to more completely explain the concept of the present invention to those with average knowledge in the art. Identical reference numerals denote identical elements throughout. Furthermore, various elements and areas in the drawings are depicted schematically. Accordingly, the concept of the present invention is not limited by the relative sizes or spacing depicted in the accompanying drawings.

[0036] Terms such as first, second, etc. may be used to describe various components, but said components are not limited by said terms. These terms are used solely for the purpose of distinguishing one component from another. For example, without departing from the scope of the concept of the present invention, the first component may be named the second component, and conversely, the second component may be named the first component.

[0037] The terms used in this application are used merely to describe specific embodiments and are not intended to limit the concept of the invention. The singular expression includes the plural expression unless the context clearly indicates otherwise. In this application, expressions such as “comprising” or “having” are intended to indicate the existence of the features, number, steps, actions, components, parts, or combinations thereof described in the specification, and should be understood as not precluding the existence or addition of one or more other features, numbers, actions, components, parts, or combinations thereof.

[0038] Unless otherwise defined, all terms used herein, including technical and scientific terms, have the same meaning as commonly understood by those skilled in the art to which the concept of the present invention pertains. Furthermore, it will be understood that commonly used terms, such as those defined in advance, should be interpreted as having meanings consistent with their intent in the context of the relevant technology, and should not be interpreted in an overly formal sense unless explicitly defined herein.

[0039] Where an embodiment can be implemented differently, a specific process sequence may be performed differently from the order described. For example, two processes described in succession may be performed substantially simultaneously or in the reverse order of the description.

[0040] In the accompanying drawings, variations of the depicted shapes may be expected, for example, depending on manufacturing technology and / or tolerances. Accordingly, embodiments of the present invention should not be interpreted as being limited to specific shapes of the areas depicted herein, but should include, for example, variations in shape resulting from the manufacturing process. All terms "and / or" used herein include each of the mentioned components and all combinations of one or more thereof. Additionally, the term "substrate" as used herein may refer to the substrate itself, or a laminated structure including the substrate and a certain layer or film formed on its surface. Furthermore, the term "surface of the substrate" in this specification may refer to the exposed surface of the substrate itself, or the outer surface of a certain layer or film formed on the substrate.

[0041]

[0042] Hereinafter, one aspect of the present invention for achieving the first technical objective mentioned above will be described.

[0043]

[0044] (1st embodiment)

[0045] FIG. 1 is a flowchart showing a method for manufacturing a secondary battery according to one embodiment of the present invention, FIG. 2 is a diagram showing a stacking step (S1) in a method for manufacturing a secondary battery according to one embodiment of the present invention, and FIG. 3 is a planar diagram showing a stacking step (S1) in which first electrodes (1141), a separator (112), and second electrodes (1151) are stacked in a method for manufacturing a secondary battery according to one embodiment of the present invention.

[0046] FIG. 4 is a drawing showing a stacking portion (11) of a secondary battery manufacturing device (1) according to one embodiment of the present invention, and FIG. 5 is a drawing showing a secondary battery manufacturing device (1) according to one embodiment of the present invention.

[0047]

[0048] Referring to FIGS. 1 to 5, a secondary battery manufacturing method according to one embodiment of the present invention may include a stacking step (S1), a separator cutting step (S2), a wrapping step (S3), a thermal compression step, and an electrode assembly cutting step (S4).

[0049] The above stacking step (S1) can be performed by moving the separator (112) back and forth to fold it in a zigzag shape, and by alternately arranging a plurality of first electrodes (1141) and a plurality of second electrodes (1151) between the separator (112) to form a plurality of electrode assemblies.

[0050] The above stacking step (S1) can improve the productivity of the electrode assembly of the secondary battery by stacking the separator (112) by moving it back and forth to fold it in a zigzag shape and alternately arranging a plurality of first electrodes (1141) and a plurality of second electrodes (1151) between the separator (112) to form a plurality of electrode assemblies.

[0051] In some embodiments, the first electrode (1141) and the second electrode (1151) may be formed by applying an electrode active material, such as a transition metal oxide, to an electrode current collector plate. The first electrode (1141) and the second electrode (1151) may further include an electrode-free portion where the electrode active material is not applied. The electrode-free portion may provide a current flow path.

[0052] In some embodiments, the electrode-free portion may protrude and extend to one side of the electrode to form an electrode tab. A current flow path to the outside may be provided through the electrode tab.

[0053] The above stacking step (S1) can supply the separator (112) to the separator table (111) by moving it back and forth left and right to fold it in a zigzag shape.

[0054] By alternately arranging a plurality of first electrodes (1141) and a plurality of second electrodes (1151) between the separator (112) that folds in a zigzag shape, a plurality of electrode assemblies can be formed that may include two or more electrode assemblies.

[0055] In some embodiments, the separator (112) is formed to be larger than the size of the first electrode (1141) and the second electrode (1151) to prevent an electrical short circuit between the first electrode (1141) and the second electrode (1151). To prevent the electrical short circuit, the width of the separator (112) may be formed to be larger than the width of the first electrode (1141) and the second electrode (1151).

[0056] In some embodiments, the separator cutting step (S2) may provide an extra separator (1122) by cutting the separator (112) to a length such that it can wrap around the plurality of electrode assemblies.

[0057] In some embodiments, the separator cutting step (S2) may be performed after the stacking step (S1).

[0058] In some embodiments, the length of the extra separator (1122) that can wrap around the electrode assembly may be such that the end of the extra separator (1122) wraps around the electrode assembly at least one full turn.

[0059] The wrapping step (S3) above can wrap the plurality of electrode assemblies with the extra separator (1122).

[0060] Through the above separator cutting step (S2) and wrapping step (S3), the displacement of the plurality of first electrodes (1141) and the plurality of second electrodes (1151) placed between the separator (112) can be prevented.

[0061]

[0062] The electrode assembly cutting step (S4) can be performed by cutting the separator (112) located between the plurality of electrode assemblies to separate them into individual electrode assemblies (14).

[0063] In some embodiments, the productivity of the electrode assembly of a secondary battery can be improved by producing two or more individual electrode assemblies (14) by cutting the plurality of electrode assemblies.

[0064] The electrode assembly cutting step (S4) can be performed by laser cutting or blade cutting, and after the electrode assembly cutting step (S4), the individual electrode assembly (14) can be withdrawn in the opposite direction.

[0065]

[0066] Specifically, the stacking step (S1) may include a base separator placement step (S11), a plurality of first electrode placement step (S12), a second direction separator placement step (S13), a plurality of second electrode placement step (S14), and a first direction separator placement step (S15).

[0067] In the above base separator placement step (S11), the separator (112) can be placed in a first direction.

[0068] The above first direction may be, for example, the +x direction.

[0069] The above step of arranging a plurality of first electrodes (S12) may arrange a plurality of first electrodes (1141) on the base separator (1121) so as to be spaced apart from each other in the y direction.

[0070] The second direction separator placement step (S13) can be formed such that a separator (112) connected to the base separator (1121) is folded onto the base separator (1121) on which a plurality of spaced-apart first electrodes (1141) are arranged, and is placed in a second direction opposite to the first direction.

[0071] The above second direction may be, for example, the -x direction.

[0072] The step of arranging a plurality of second electrodes above may involve arranging a plurality of second electrodes (1151) on the second direction separator (112) so as to be spaced apart from each other in the y direction.

[0073] The first direction separator placement step (S15) can be formed such that the separator (112) connected to the second direction separator (112) is folded onto the second direction separator (112) on which a plurality of spaced-apart second electrodes (1151) are arranged, and is placed in a first direction opposite to the second direction.

[0074] In some embodiments, the plurality of electrode assemblies may be one of a monocell having different types of electrodes located at both ends and a bicell having the same type of electrodes located at both ends.

[0075] In some embodiments, the plurality of electrode assemblies up to the first direction separator placement step (S15) are monocells of different types of electrodes located at both ends.

[0076] In some embodiments, the plurality of electrode assemblies, in which the plurality of first electrode placement step (S12) and the second directional separator placement step (S13) are additionally performed after the first directional separator placement step (S15), are of the bicell type in which the types of electrodes located at both ends are the same.

[0077] In some embodiments, in the stacking step (S1), the images projected perpendicularly to the xy plane of the first electrode body portions (1141-1) of the plurality of first electrodes (1141) and the second electrode body portions (1151-1) of the plurality of second electrodes (1151) may be configured to overlap each other.

[0078] The above xy plane refers to a plane substantially parallel to the plane on which the separator (112) of the electrode assembly, a plurality of first electrodes (1141), and a plurality of second electrodes (1151) are stacked.

[0079]

[0080] In some embodiments, as shown in FIG. 3, when the first electrode body portions (1141-1) of the plurality of first electrodes (1141) and the second electrode body portions (1151-1) of the plurality of second electrodes (1151) are stacked with a separator in between, the first electrode body portions (1141-1) of the plurality of first electrodes (1141) and the second electrode body portions (1151-1) of the plurality of second electrodes (1151) are superimposed perpendicularly to the xy plane so that the electrical characteristics of the plurality of first electrodes (1141) and the plurality of second electrodes (1151) can be maintained constant and the positions of the tabs provided on the plurality of first electrodes (1141) and the plurality of second electrodes (1151) can be adjusted constant.

[0081]

[0082] In some embodiments, in the stacking step (S1), the plurality of first electrodes (1141) and the plurality of second electrodes (1151) may be configured such that the tabs (1141-2) provided on each of the plurality of first electrodes (1141) and the tabs (1151-2) provided on each of the plurality of second electrodes (1151) are respectively disposed on the outer side of the corner portion excluding the folded corner portion (112a) of the separator (112).

[0083] In some embodiments, the plurality of first electrodes (1141) and the plurality of second electrodes (1151) are arranged such that the tabs (1141-2) provided on each of the plurality of first electrodes (1141) and the tabs (1151-2) provided on each of the plurality of second electrodes (1151) are respectively placed on the outer side of the corner portion excluding the folded corner portion (112a) of the separator (112), thereby preventing the plurality of first electrode tabs (1141-2) provided on the plurality of first electrodes (1141) and the plurality of second electrode tabs (1151-2) provided on the plurality of second electrodes (1151) from being damaged by the folded corner portion (112a).

[0084]

[0085] In some embodiments, the number of spaced-apart first electrodes (1141) may be two, and the number of spaced-apart second electrodes (1151) may be two. For example, the two first electrodes (1141) may be spaced apart from each other in the y-direction, and the two second electrodes (1151) may be spaced apart from each other in the y-direction.

[0086] In some embodiments, the first electrode tab (1141-2) provided on one of the two first electrodes (1141) may be positioned outside the first side corner (112b), which is one of the two side corners adjacent to the folded corner portion (112a) of the separator (112).

[0087] In some embodiments, the first electrode tab (1141-2) provided on the other of the two first electrodes (1141) may be positioned on the outside of the second side corner (112c), which is the other of the two side corners adjacent to the folded corner portion (112a) of the separator (112).

[0088] In some embodiments, the first electrode tab (1141-2) provided on one of the two first electrodes (1141) and the first electrode tab (1141-2) provided on the other may be arranged asymmetrically with respect to the surface where the separator (112) described later is cut. Specifically, in the stacking step (S1), the first electrode tab (1141-2) provided on one of the two first electrodes (1141) and the first electrode tab (1141-2) provided on the other may be arranged such that their x-direction positions do not overlap when viewed from the y-direction.

[0089] For example, the separator (112) may include a first electrode assembly region and a second electrode assembly region separated based on the surface where the separator (112) is cut. The first electrode assembly region and the second electrode assembly region may be arranged in the y direction. The first electrode assembly region may be a region including a first side edge (112b). The second electrode assembly region may be a region including a second side edge (112c).

[0090] In some embodiments, one of the two first electrodes (1141) may be placed in the first electrode assembly area, and the other of the two first electrodes (1141) may be placed in the second electrode assembly area. In this case, the first electrode tab (1141-2) of the first electrode (1141) placed in the first electrode assembly area and the first electrode tab (1141-2) of the first electrode (1141) placed in the second electrode assembly area may be arranged asymmetrically with respect to the surface where the separator (112) is cut.

[0091] Accordingly, when individual electrode assemblies (14) formed through the electrode assembly cutting step (S4) described later are aligned to have the same tab extraction direction (e.g., +y direction), an image projected perpendicularly onto the xy plane of the first electrode tabs (1141-2) provided on each of the first electrodes (1141) can be superimposed. Similarly, an image projected perpendicularly onto the xy plane of the second electrode tabs (1151-2) provided on each of the plurality of second electrodes (1151) can be superimposed. That is, the first electrode tabs (1141-2) and the second electrode tabs (1151-2) can be arranged in groups at the same location, and since tabs of the same type are aligned in a row for each group, it becomes easy to manage or connect tabs of the same type collectively in subsequent processes.

[0092] In some embodiments, a second electrode tab (1151-2) provided on one of the two second electrodes (1151) may be positioned outside a first side corner (112b), which is one of the two side corners adjacent to the folded corner portion (112a) of the separator (112).

[0093] In some embodiments, the second electrode tab (1151-2) provided on the other of the two second electrodes (1151) may be positioned on the outside of the second side corner (112c), which is the other of the two side corners adjacent to the folded corner portion (112a) of the separator (112).

[0094] In some embodiments, the second electrode tab (1151-2) provided on one of the two second electrodes (1151) and the second electrode tab (1151-2) provided on the other may be arranged asymmetrically with respect to the surface where the separator (112) described later is cut. Specifically, in the stacking step (S1), the second electrode tab (1151-2) provided on one of the two second electrodes (1151) and the second electrode tab (1151-2) provided on the other may be arranged such that their x-direction positions do not overlap when viewed from the y-direction.

[0095] In some embodiments, one of the two second electrodes (1151) may be placed in the first electrode assembly area, and the other of the two second electrodes (1151) may be placed in the second electrode assembly area. In this case, the second electrode tab (1151-2) of the second electrode (1151) placed in the first electrode assembly area and the second electrode tab (1151-2) of the second electrode (1151) placed in the second electrode assembly area may be arranged asymmetrically with respect to the surface where the separator (112) is cut.

[0096] Accordingly, when individual electrode assemblies (14) formed through the electrode assembly cutting step (S4) described later are aligned to have the same tab extraction direction (e.g., +y direction), an image projected perpendicularly onto the xy plane of the second electrode tabs (1151-2) provided on each of the second electrodes (1151) can be superimposed. Similarly, an image projected perpendicularly onto the xy plane of the second electrode tabs (1151-2) provided on each of the multiple second electrodes (1151) can be superimposed. That is, the second electrode tabs (1151-2) and the second electrode tabs (1151-2) can be arranged in groups at the same location, and since tabs of the same type are aligned in a row for each group, it becomes easy to manage or connect tabs of the same type collectively in subsequent processes.

[0097] By placing electrode tabs provided on the two first electrodes (1141) and the two second electrodes (1151) at the two side corners (112b, 112c) adjacent to the folded corner portion (112a) of the separator (112), damage to the plurality of first electrode tabs (1141-2) provided on the plurality of first electrodes (1141) and the plurality of second electrode tabs (1151-2) provided on the plurality of second electrodes (1151) can be prevented during the electrode assembly wrapping step (S3), and the two first electrodes (1141) and the two second electrodes (1151) can be arranged in a line with respect to the wrapping direction during the electrode assembly wrapping step (S3), so that the separator (112) can firmly wrap the electrode assembly.

[0098] In some embodiments, as illustrated in FIG. 5, in the wrapping step (S3), the extra separator (1122) may be configured to wrap the plurality of electrode assemblies in a direction that wraps the opposite corner of the folded corner (112a) of the separator (112) of the plurality of electrode assemblies.

[0099] In the wrapping step (S3), the extra separator (1122) is configured to wrap the plurality of electrode assemblies in a direction that wraps the opposite corner portion (112a) of the folded corner portion (112a) of the separator (112), thereby preventing damage to the plurality of first electrode tabs (1141-2) provided on the plurality of first electrodes (1141) and the plurality of second electrode tabs (1151-2) provided on the plurality of second electrodes (1151) during the electrode assembly wrapping step (S3), and allowing the plurality of first electrode tabs (1141-2) and the plurality of second electrode tabs (1151-2) to be exposed outside the separator (112) and connected to an external terminal.

[0100] In some embodiments, the first electrode tabs (1141-2) provided on each of the plurality of first electrodes (1141) and the second electrode tabs (1151-2) provided on each of the plurality of second electrodes (1151) may not overlap when projected perpendicularly to the xy plane.

[0101] The first electrode tabs (1141-2) and the second electrode tabs (1151-2) can prevent short circuits between the first electrode (1141) and the second electrode (1151) by ensuring that the images projected perpendicularly to the xy plane are spaced apart from each other and do not overlap.

[0102] In some embodiments, the stacking step (S1) for forming the plurality of electrode assemblies may include: a step of stacking a type a first electrode (1141a) having a type a first electrode tab (1141a-2) among a plurality of first electrodes (1141) in an area corresponding to the individual electrode assembly (14); and a step of stacking a type b first electrode (1141b) having a type b first electrode tab (1141b-2) at a different position from the type a first electrode tab (1141a-2) among a plurality of first electrodes (1141) in an area corresponding to the individual electrode assembly (14).

[0103] The stacking step (S1) for forming the plurality of electrode assemblies comprises: a step of stacking a type a first electrode (1141a) having a type a first electrode tab (1141a-2) among a plurality of first electrodes (1141) in an area corresponding to the individual electrode assembly (14); and a step of stacking a type b first electrode (1141b) having a type b first electrode tab (1141b-2) at a different location from the type a first electrode tab (1141a-2) among a plurality of first electrodes (1141) in an area corresponding to the individual electrode assembly (14). By doing so, when the tabs are gathered to form a lead portion during future cell stacking, the curvature of the tabs located on the outer edge can be reduced, thereby preventing damage to the tabs located on the outer edge.

[0104] Hereinafter, cases in which a total of 20 first electrodes (1141) are stacked according to comparative examples and embodiments are described, respectively. For example, in a comparative example, 20 first electrodes (1141) in which all tabs are formed at the same location may be stacked. For example, in an embodiment, a type a first electrode (1141a) having 10 type a first electrode tabs (1141a-2) and a type b first electrode (1141b) having 10 type b first electrode tabs (1141b-2) may be stacked.

[0105] According to the comparative example, since the tabs of the 20 first electrodes (1141) overlap at one point, heat and pressure may be concentrated in the thick laminated portion during welding. In addition, the tabs may undergo bending deformation or twisting, and if the bending is severe, the risk of tab breakage or poor bonding may increase.

[0106] According to the embodiment, the type a first electrode tabs (1141a-2) of the 10 type a first electrodes (1141a) can be welded together, and the type b first electrode tabs (1141b-2) of the 10 type b first electrodes (1141b) can be welded together. Thus, the stacking thickness of the tabs at each location can be distributed to half the level. As a result, stress concentration during tab welding is alleviated, the degree of tab bending is reduced, and the risk of wire breakage is lowered accordingly.

[0107] As a result, the number of stacked first electrodes (1141) can be increased, thereby increasing the capacity of the secondary battery electrode assembly including them.

[0108] In addition, according to the comparative example, the length of each tab must be designed to be long to align the tab ends at the upper and lower electrodes, and there is a risk of defects occurring where the tab bends or folds.

[0109] On the other hand, according to the embodiment, the tab length can be shortened by forming the type a first electrode tab (1141a-2) of the type a first electrode (1141a) and the type b first electrode tab (1141b-2) of the type b first electrode (1141b) at different locations. As a result, the risk of defects occurring, such as the tab bending or folding during the manufacturing process, is reduced.

[0110] In some embodiments, one or more type a first electrodes (1141a) and one or more type b first electrodes (1141b) at different positions of the electrode tabs may be stacked alternately, or a plurality of type a first electrodes (1141a) may be stacked and then a plurality of type b first electrodes (1141b) may be stacked.

[0111] In some embodiments, the stacking step (S1) for forming the plurality of electrode assemblies may include: a step of stacking a type a second electrode (1151a) having a type a second electrode tab (1151a-2) among a plurality of second electrodes (1151) in an area corresponding to the individual electrode assembly (14); and a step of stacking a type b second electrode (1151b) having a type b second electrode tab (1151b-2) at a different location from the type a second electrode tab (1151a-2) among a plurality of second electrodes (1151) in an area corresponding to the individual electrode assembly (14).

[0112] The stacking step (S1) for forming the plurality of electrode assemblies comprises: a step of stacking a type a second electrode (1151a) having a type a second electrode tab (1151a-2) among a plurality of second electrodes (1151) in an area corresponding to the individual electrode assembly (14); and a step of stacking a type b second electrode (1151b) having a type b second electrode tab (1151b-2) at a different location from the type a second electrode tab (1151a-2) among a plurality of second electrodes (1151) in an area corresponding to the individual electrode assembly (14); thereby, when the tabs are gathered to form a lead portion during cell stacking in the future, the curvature of the tabs located on the outer edge can be reduced, and thus damage to the tabs located on the outer edge can be prevented.

[0113] Hereinafter, cases in which a total of 20 second electrodes (1151) are stacked according to comparative examples and embodiments are described, respectively. For example, in a comparative example, 20 second electrodes (1151) in which all tabs are formed at the same location may be stacked. For example, in an embodiment, a second electrode (1151a) having 10 second electrode tabs of type a (1151a-2) and a second electrode (1151b) having 10 second electrode tabs of type b (1151b-2) may be stacked.

[0114] According to the comparative example, since the tabs of the 20 second electrodes (1151) overlap at one point, heat and pressure may be concentrated in the thick laminated portion during welding. In addition, the tabs may undergo bending deformation or twisting, and if the bending is severe, the risk of tab breakage or poor bonding may increase.

[0115] According to the embodiment, the type a second electrode tabs (1151a-2) of the 10 type a second electrodes (1151a) can be welded together, and the type b second electrode tabs (1151b-2) of the 10 type b second electrodes (1151b) can be welded together. Thus, the stacking thickness of the tabs at each location can be distributed to half the level. As a result, stress concentration during tab welding is relieved, the degree of tab bending is reduced, and the risk of wire breakage is lowered accordingly.

[0116] As a result, the number of stacked second electrodes (1151) can be increased, thereby increasing the capacity of the secondary battery electrode assembly including them.

[0117] In addition, according to the comparative example, the length of each tab must be designed to be long to align the tab ends at the upper and lower electrodes, and there is a risk of defects occurring where the tab bends or folds.

[0118] On the other hand, according to the embodiment, the tab length can be shortened by forming the type a second electrode tab (1151a-2) of the type a second electrode (1151a) and the type b second electrode tab (1151b-2) of the type b second electrode (1151b) at different locations. As a result, the risk of defects occurring, such as the tab bending or folding during the manufacturing process, is reduced.

[0119] In some embodiments, one or more type a second electrodes (1151a) and one or more type b second electrodes (1151b) at different positions of the electrode tabs may be stacked alternately, or a plurality of type a second electrodes (1151a) may be stacked and then a plurality of type b second electrodes (1151b) may be stacked.

[0120]

[0121] In some embodiments, the images projected perpendicularly onto the xy plane of the first electrode tabs (1141-2) provided on each of the two first electrodes (1141) and the first electrode tabs (1141-2) provided on each of the other multiple first electrodes (1141) that are odd-numbered closer to the two first electrodes (1141) may be spaced apart from each other and not overlap.

[0122] In some embodiments, the images projected perpendicularly onto the xy plane of the second electrode tabs (1151-2) provided on each of the two second electrodes (1151) and the second electrode tabs (1151-2) provided on each of the other multiple second electrodes (1151) that are odd-numbered closer to the two second electrodes (1151) may be spaced apart from each other and not overlap.

[0123] By projecting the electrode tabs provided on the other two first electrodes (1141) and second electrodes (1151) that are odd-numbered closer to the two first electrodes (1141) and second electrodes (1151) perpendicularly to the xy plane so that they are spaced apart from each other and do not overlap, the curvature of the tabs located on the outer edge can be reduced when the tabs are gathered to form a lead portion during cell stacking in the future, thereby preventing damage to the tabs located on the outer edge.

[0124] In some embodiments, the first electrode tabs (1141-2) provided on each of the two first electrodes (1141) and the first electrode tabs (1141-2) provided on each of the other two first electrodes (1141) that are evenly close to the plurality of first electrodes (1141) may be superimposed on each other perpendicularly to the xy plane.

[0125] In some embodiments, the images of the second electrode tabs (1151-2) provided on each of the two second electrodes (1151) and the second electrode tabs (1151-2) provided on each of the other two second electrodes (1151) that are evenly close to the plurality of second electrodes (1151) and the images projected perpendicularly onto the xy plane may overlap each other.

[0126] The electrode tabs provided on the other two first electrodes (1141) and second electrodes (1151), which are each the evenly numbered closest to the two first electrodes (1141) and second electrodes (1151), are projected perpendicularly onto the xy plane and overlap each other, thereby making it easy to charge and discharge each cell.

[0127]

[0128] (2nd Example)

[0129] FIG. 1 is a flowchart showing a method for manufacturing a secondary battery according to one embodiment of the present invention, and FIG. 3 is a planar drawing showing a stacking step (S1) in which first electrodes (1141), a separator (112), and second electrodes (1151) are stacked in a method for manufacturing a secondary battery according to one embodiment of the present invention.

[0130] FIG. 4 is a conceptual drawing showing a stacking portion (11) of a secondary battery manufacturing device (1) according to one embodiment of the present invention, and FIG. 5 is a conceptual drawing showing a secondary battery manufacturing device (1) according to one embodiment of the present invention.

[0131]

[0132] Referring to FIGS. 1 to 5, a secondary battery manufacturing apparatus (1) according to one embodiment of the present invention may include a stacking section (11), a separator cutting section (1133), an electrode assembly wrapping section (12), and an electrode assembly cutting section (13).

[0133] The above stacking portion (11) can be stacked to form multiple electrode assemblies by alternately arranging multiple first electrodes (1141) and multiple second electrodes (1151) between the separators (112) while moving the separator (112) back and forth to fold it in a zigzag shape.

[0134] The above stacking section (11) may include a separator supply roll (1131) that supplies a separator (112) and a separator roller (1132) that moves the separator (112) back and forth.

[0135] The above stacking portion (11) can improve the productivity of the electrode assembly of the secondary battery by stacking the separator (112) by moving it back and forth to fold it in a zigzag shape and alternately arranging a plurality of first electrodes (1141) and a plurality of second electrodes (1151) between the separator (112) to form a plurality of electrode assemblies.

[0136] The first electrode (1141) and the second electrode (1151) can be formed by applying an electrode active material to an electrode current collector plate. The first electrode (1141) and the second electrode (1151) may further include an electrode-free portion where the electrode active material is not applied. The electrode-free portion may provide a current flow path. The electrode-free portion may protrude and extend to one side of the electrode to form an electrode tab. A current flow path to the outside may be provided through the electrode tab.

[0137] The above separator cutting section (1133) can provide an extra separator (1122) by cutting the separator (112) with a cutter (131) to a length that can wrap the plurality of electrode assemblies.

[0138] The length of the extra separator (1122) that can wrap around the electrode assembly may be such that the extra separator (1122) wraps around the circumference of the electrode assembly at least once.

[0139] In some embodiments, the separator cutting part (1133) may cut the separator (112) with a laser or a blade, but the present invention is not limited thereto.

[0140] In some embodiments, the electrode assembly wrapping portion (12) may wrap the plurality of electrode assemblies with the extra separator (1122).

[0141] In some embodiments, the electrode assembly cutting portion (13) can cut the separator (112) located between the plurality of electrode assemblies to separate them into individual electrode assemblies (14).

[0142] In some embodiments, the electrode assembly cutting part (13) may cut the separator (112) located between the plurality of electrode assemblies with a laser or a blade, but the present invention is not limited thereto.

[0143]

[0144] Specifically, the stacking portion (11) may include a separator table (111), a separator supply portion (113), a first electrode placement portion (114), and a second electrode placement portion (115).

[0145] The above separator table (111) may have a zigzag folded separator (112) size in which a plurality of electrodes can be arranged and accommodated.

[0146] The above-mentioned separator supply unit (113) can supply a separator (112) that is folded in a zigzag shape by moving the separator (112) back and forth.

[0147] The first electrode placement section (114) can arrange a plurality of first electrodes (1141) spaced apart from each other between the separator membranes (112) that are supplied and folded in a zigzag shape.

[0148] In some embodiments, the first electrode placement portion (114) may include a first electrode storage portion (114a) and a first electrode placement arm (114b).

[0149] In some embodiments, the first electrode storage unit (114a) can store the plurality of first electrodes (1141).

[0150] In some embodiments, the first electrode placement arm (114b) can arrange the stored plurality of first electrodes (1141) spaced apart from each other between the separator (112).

[0151] In some embodiments, the second electrode placement portion (115) may arrange a plurality of second electrodes (1151) spaced apart from each other between the separator membranes (112) that are subsequently folded and supplied in a zigzag manner after the arrangement of the plurality of first electrodes (1141).

[0152] In some embodiments, the second electrode placement portion (115) may include a second electrode storage portion (115a) and a second electrode placement arm (115b).

[0153] In some embodiments, the second electrode storage unit (115a) can store the plurality of second electrodes (1151).

[0154] In some embodiments, the second electrode placement arm (115b) can arrange the stored plurality of second electrodes (1151) spaced apart from each other between the separator (112).

[0155]

[0156] In some embodiments, the first electrode placement portion (114) and the second electrode placement portion (115) may be configured to be positioned so that the first electrode body portions (1141-1) of the plurality of first electrodes (1141) and the second electrode body portions (1151-1) of the plurality of second electrodes (1151) projected perpendicularly to the xy plane can be superimposed on each other.

[0157] The above xy plane refers to a plane substantially parallel to the plane on which the separator (112) of the electrode assembly, a plurality of first electrodes (1141), and a plurality of second electrodes (1151) are stacked.

[0158] In some embodiments, as shown in FIG. 3, when the first electrode body portions (1141-1) of the plurality of first electrodes (1141) and the second electrode body portions (1151-1) of the plurality of second electrodes (1151) are stacked with a separator in between, the first electrode body portions (1141-1) of the plurality of first electrodes (1141) and the second electrode body portions (1151-1) of the plurality of second electrodes (1151) are superimposed perpendicularly to the xy plane so that the electrical characteristics of the plurality of first electrodes (1141) and the plurality of second electrodes (1151) can be maintained constant and the positions of the tabs provided on the plurality of first electrodes (1141) and the plurality of second electrodes (1151) can be adjusted constant.

[0159]

[0160] In some embodiments, the first electrode placement portion (114) and the second electrode placement portion (115) may be configured to arrange the plurality of first electrodes (1141) and the plurality of second electrodes (1151) such that the tabs provided on each of the plurality of first electrodes (1141) and the tabs provided on each of the plurality of second electrodes (1151) are respectively arranged on the outer side of the corner portion excluding the folded corner portion (112a) of the separator (112).

[0161] The first electrode placement section (114) and the second electrode placement section (115) can prevent the multiple first electrodes (1141) and the multiple second electrodes (1151) from being damaged by the folded corner section (112a) by arranging the multiple first electrodes (1141) and the multiple second electrodes (1151) such that the tabs (1141-1) provided on each of the multiple first electrodes (1141) and the tabs (1151-1) provided on each of the multiple second electrodes (1151) are respectively arranged on the outer side of the corner section excluding the folded corner section (112a) of the separator (112).

[0162] In some embodiments, the number of spaced-apart first electrodes (1141) may be two, and the number of spaced-apart second electrodes (1151) may be two. For example, the two first electrodes (1141) may be spaced apart from each other in the y-direction, and the two second electrodes (1151) may be spaced apart from each other in the y-direction.

[0163] In some embodiments, the first electrode placement portion (114) may stack the two first electrodes (1141) such that a first electrode tab (1141-2) provided on one of the two first electrodes (1141) is positioned outside a first side corner (112b) which is one of the two side corners adjacent to the folded corner portion (112a) of the separator (112).

[0164] In some embodiments, the first electrode placement portion (114) may stack the two first electrodes (1141) such that a first electrode tab (1141-2) provided on the other of the two first electrodes (1141) is positioned outside the second side corner (112c), which is the other of the two side corners adjacent to the folded corner portion (112a) of the separator (112).

[0165] In some embodiments, the first electrode arrangement (114) may stack the two first electrodes (1141) such that the first electrode tab (1141-2) provided on one of the two first electrodes (1141) and the first electrode tab (1141-2) provided on the other are asymmetric with respect to the surface where the separator (112) is cut. Specifically, the first electrode arrangement (114) may stack the two first electrodes (1141) such that the first electrode tab (1141-2) provided on one of the two first electrodes (1141) and the first electrode tab (1141-2) provided on the other do not overlap in the x-direction position when viewed from the y-direction.

[0166] For example, the separator (112) may include a first electrode assembly region and a second electrode assembly region separated based on the surface where the separator (112) is cut. The first electrode assembly region and the second electrode assembly region may be arranged in the y direction. The first electrode assembly region may be a region including a first side edge (112b). The second electrode assembly region may be a region including a second side edge (112c).

[0167] In some embodiments, the first electrode placement portion (114) may place one of the two first electrodes (1141) in the first electrode assembly area and place the other of the two first electrodes (1141) in the second electrode assembly area. At this time, the first electrode tab (1141-2) of the first electrode (1141) placed in the first electrode assembly area and the first electrode tab (1141-2) of the first electrode (1141) placed in the second electrode assembly area may be placed asymmetrically with respect to the surface where the separator (112) is cut.

[0168] Accordingly, when individual electrode assemblies (14) are aligned to have the same tab extraction direction (e.g., +y direction), an image projected perpendicularly onto the xy plane of the first electrode tabs (1141-2) provided on each of the first electrodes (1141) can be superimposed. Similarly, an image projected perpendicularly onto the xy plane of the second electrode tabs (1151-2) provided on each of the plurality of second electrodes (1151) can be superimposed. That is, the first electrode tabs (1141-2) and the second electrode tabs (1151-2) can be arranged in groups at the same location, and since tabs of the same type are aligned in a row for each group, it becomes easy to manage or connect tabs of the same type collectively.

[0169] In some embodiments, the second electrode placement portion (115) may stack the two second electrodes (1151) such that a second electrode tab (1151-2) provided on one of the two second electrodes (1151) is positioned outside a first side corner (112b), which is one of the two side corners adjacent to the folded corner portion (112a) of the separator (112).

[0170] In some embodiments, the second electrode placement portion (115) may stack the two second electrodes (1151) such that a second electrode tab (1151-2) provided on the other of the two second electrodes (1151) is positioned outside the second side corner (112c), which is the other of the two side corners adjacent to the folded corner portion (112a) of the separator (112).

[0171] In some embodiments, the second electrode placement portion (115) may stack the two second electrodes (1151) such that the second electrode tab (1151-2) provided on one of the two second electrodes (1151) and the second electrode tab (1151-2) provided on the other are asymmetric with respect to the surface where the separator (112) is cut. Specifically, the second electrode placement portion (115) may stack the two second electrodes (1151) such that the second electrode tab (1151-2) provided on one of the two second electrodes (1151) and the second electrode tab (1151-2) provided on the other do not overlap in the X-direction position when viewed from the Y-direction.

[0172] In some embodiments, the second electrode placement portion (115) may place one of the two second electrodes (1151) in the first electrode assembly area and place the other of the two second electrodes (1151) in the second electrode assembly area. At this time, the second electrode tab (1151-2) of the second electrode (1151) placed in the first electrode assembly area and the second electrode tab (1151-2) of the second electrode (1151) placed in the second electrode assembly area may be placed asymmetrically with respect to the surface where the separator (112) is cut.

[0173] Accordingly, when individual electrode assemblies (14) are aligned to have the same tab extraction direction (e.g., +y direction), an image projected perpendicularly onto the xy plane of the second electrode tabs (1151-2) provided on each of the second electrodes (1151) can be superimposed. Similarly, an image projected perpendicularly onto the xy plane of the second electrode tabs (1151-2) provided on each of the multiple second electrodes (1151) can be superimposed. That is, the second electrode tabs (1151-2) and the second electrode tabs (1151-2) can be arranged in groups at the same location, and since tabs of the same type are aligned in a row for each group, it becomes easy to manage or connect tabs of the same type collectively.

[0174] By placing electrode tabs provided on the two first electrodes (1141) and the two second electrodes (1151) at the two side corners (112b, 112c) adjacent to the folded corner portion (112a) of the separator (112), damage to the plurality of first electrode tabs (1141-2) provided on the plurality of first electrodes (1141) and the plurality of second electrode tabs (1151-2) provided on the plurality of second electrodes (1151) can be prevented during the electrode assembly wrapping step (S3), and the two first electrodes (1141) and the two second electrodes (1151) can be arranged in a line with respect to the wrapping direction during the electrode assembly wrapping step (S3), so that the separator (112) can firmly wrap the electrode assembly.

[0175] In some embodiments, the electrode assembly wrapping portion (12) may be configured such that the extra separator (1122) wraps the plurality of electrode assemblies in a direction such that the opposite corner portion (112a) of the folded corner portion (112) of the separator (112) of the plurality of electrode assemblies wraps the plurality of electrode assemblies.

[0176] The electrode assembly wrapping portion (12) is configured such that the extra separator (1122) wraps the plurality of electrode assemblies in a direction that wraps the opposite corner portion (112a) of the folded corner portion (112a) of the separator (112) of the plurality of electrode assemblies, thereby preventing the plurality of first electrode tabs (1141-2) provided on the plurality of first electrodes (1141) and the plurality of second electrode tabs (1151-2) provided on the plurality of second electrodes (1151) from being damaged by the folded corner portion (112a), and the plurality of first electrode tabs (1141-2) and the plurality of second electrode tabs (1151-2) can be exposed outside the separator (112) to be connected to an external terminal.

[0177] In some embodiments, the first electrode placement portion (114) and the second electrode placement portion (115) may be configured such that the images projected perpendicularly to the xy plane of the first electrode tabs (1141-2) provided on each of the plurality of first electrodes (1141) and the second electrode tabs (1151-2) provided on each of the plurality of second electrodes (1151) are spaced apart from each other and do not overlap.

[0178] The first electrode tabs (1141-2) and the second electrode tabs (1151-2) are configured such that the images projected perpendicularly onto the xy plane are spaced apart from each other and do not overlap, thereby preventing a short circuit between the first electrode (1141) and the second electrode (1151).

[0179] In some embodiments, the stacking portion (11) may be configured to stack a type a first electrode (1141a) having a type a first electrode tab (1141a-2) among a plurality of first electrodes (1141) in an area corresponding to the individual electrode assembly (14), and to stack a type b first electrode (1141b) having a type b first electrode tab (1141b-2) at a different position from the type a first electrode tab (1141a-2) among a plurality of first electrodes (1141) in an area corresponding to the individual electrode assembly (14).

[0180] The stacking portion (11) is configured to stack a type a first electrode (1141a) having a type a first electrode tab (1141a-2) among a plurality of first electrodes (1141) in an area corresponding to the individual electrode assembly (14), and to stack a type b first electrode (1141b) having a type b first electrode tab (1141b-2) at a different location from the type a first electrode tab (1141a-2) among a plurality of first electrodes (1141) in an area corresponding to the individual electrode assembly (14), thereby reducing the curvature of the tabs located on the outer edge when the tabs are gathered to form a lead portion during cell stacking in the future, and thus preventing damage to the tabs located on the outer edge.

[0181] Hereinafter, cases in which the stacking unit (11) stacks a total of 20 first electrodes (1141) according to the comparative example and the embodiment are described respectively. For example, in the comparative example, the stacking unit (11) can stack 20 first electrodes (1141) in which all tabs are formed at the same position. For example, in the embodiment, the stacking unit (11) can stack a type a first electrode (1141a) having 10 type a first electrode tabs (1141a-2) and a type b first electrode (1141b) having 10 type b first electrode tabs (1141b-2).

[0182] According to the comparative example, since the tabs of the 20 first electrodes (1141) overlap at one point, heat and pressure may be concentrated in the thick laminated portion during welding. In addition, the tabs may undergo bending deformation or twisting, and if the bending is severe, the risk of tab breakage or poor bonding may increase.

[0183] According to the embodiment, the type a first electrode tabs (1141a-2) of the 10 type a first electrodes (1141a) can be welded together, and the type b first electrode tabs (1141b-2) of the 10 type b first electrodes (1141b) can be welded together. Thus, the stacking thickness of the tabs at each location can be distributed to half the level. As a result, stress concentration during tab welding is alleviated, the degree of tab bending is reduced, and the risk of wire breakage is lowered accordingly.

[0184] As a result, the number of stacked first electrodes (1141) can be increased, thereby increasing the capacity of the secondary battery electrode assembly including them.

[0185] In addition, according to the comparative example, the length of each tab must be designed to be long to align the tab ends at the upper and lower electrodes, and there is a risk of defects occurring where the tab bends or folds.

[0186] On the other hand, according to the embodiment, the tab length can be shortened by forming the type a first electrode tab (1141a-2) of the type a first electrode (1141a) and the type b first electrode tab (1141b-2) of the type b first electrode (1141b) at different locations. As a result, the risk of defects occurring, such as the tab bending or folding during the manufacturing process, is reduced.

[0187] In some embodiments, one or more type a first electrodes (1141a) and one or more type b first electrodes (1141b) at different positions of the electrode tabs may be stacked alternately, or a plurality of type a first electrodes (1141a) may be stacked and then a plurality of type b first electrodes (1141b) may be stacked.

[0188] In some embodiments, the stacking portion (11) may be configured to stack a type a second electrode (1151a) having a type a second electrode tab (1151a-2) among a plurality of second electrodes (1151) in an area corresponding to the individual electrode assembly (14), and to stack a type b second electrode (1151b) having a type b second electrode tab (1151b-2) at a different position from the type a second electrode tab (1151a-2) among a plurality of second electrodes (1151) in an area corresponding to the individual electrode assembly (14).

[0189] The stacking portion (11) is configured to stack a type a second electrode (1151a) having a type a second electrode tab (1151a-2) among a plurality of second electrodes (1151) in an area corresponding to the individual electrode assembly (14), and to stack a type b second electrode (1151b) having a type b second electrode tab (1151b-2) at a different location from the type a second electrode tab (1151a-2) among a plurality of second electrodes (1151) in an area corresponding to the individual electrode assembly (14), thereby reducing the curvature of the tabs located on the outer edge when the tabs are gathered to form a lead portion during cell stacking in the future, and thus preventing damage to the tabs located on the outer edge.

[0190] Hereinafter, cases in which the stacking unit (11) stacks a total of 20 second electrodes (1151) according to the comparative example and the embodiment are described respectively. For example, in the comparative example, the stacking unit (11) can stack 20 second electrodes (1151) in which all tabs are formed at the same position. For example, in the embodiment, an a-type second electrode (1151a) having 10 a-type second electrode tabs (1151a-2) and a b-type second electrode (1151b) having 10 b-type second electrode tabs (1151b-2) can be stacked.

[0191] According to the comparative example, since the tabs of the 20 second electrodes (1151) overlap at one point, heat and pressure may be concentrated in the thick laminated portion during welding. In addition, the tabs may undergo bending deformation or twisting, and if the bending is severe, the risk of tab breakage or poor bonding may increase.

[0192] According to the embodiment, the type a second electrode tabs (1151a-2) of the 10 type a second electrodes (1151a) can be welded together, and the type b second electrode tabs (1151b-2) of the 10 type b second electrodes (1151b) can be welded together. Thus, the stacking thickness of the tabs at each location can be distributed to half the level. As a result, stress concentration during tab welding is relieved, the degree of tab bending is reduced, and the risk of wire breakage is lowered accordingly.

[0193] As a result, the number of stacked second electrodes (1151) can be increased, thereby increasing the capacity of the secondary battery electrode assembly including them.

[0194] In addition, according to the comparative example, the length of each tab must be designed to be long to align the tab ends at the upper and lower electrodes, and there is a risk of defects occurring where the tab bends or folds.

[0195] On the other hand, according to the embodiment, the tab length can be shortened by forming the type a second electrode tab (1151a-2) of the type a second electrode (1151a) and the type b second electrode tab (1151b-2) of the type b second electrode (1151b) at different locations. As a result, the risk of defects occurring, such as the tab bending or folding during the manufacturing process, is reduced.

[0196] In some embodiments, one or more type a second electrodes (1151a) and one or more type b second electrodes (1151b) at different positions of the electrode tabs may be stacked alternately, or a plurality of type a second electrodes (1151a) may be stacked and then a plurality of type b second electrodes (1151b) may be stacked.

[0197] In some embodiments, the first electrode arrangement (114) may be configured such that the images projected perpendicularly onto the xy plane of the first electrode tabs (1141-2) provided on each of the two first electrodes (1141) and the first electrode tabs (1141-2) provided on each of the other plurality of first electrodes (1141) that are odd-numbered closer to the two first electrodes (1141) are spaced apart from each other and do not overlap.

[0198] In some embodiments, the second electrode arrangement (115) may be configured such that the images projected perpendicularly onto the xy plane of the first electrode tabs (1151-2) provided on each of the two first electrodes (1151) and the first electrode tabs (1151-2) provided on each of the other plurality of first electrodes (1151) that are odd-numbered closer to the two first electrodes (1151) are spaced apart from each other and do not overlap.

[0199] By projecting the electrode tabs provided on the other two first electrodes (1141) and second electrodes (1151) that are odd-numbered closer to the two first electrodes (1141) and second electrodes (1151) perpendicularly to the xy plane so that they are spaced apart from each other and do not overlap, the curvature of the tabs located on the outer edge can be reduced when the tabs are gathered to form a lead portion during cell stacking in the future, thereby preventing damage to the tabs located on the outer edge.

[0200]

[0201] In some embodiments, the first electrode arrangement (114) may be configured such that the first electrode tabs (1141-2) provided on each of the two first electrodes (1141) and the first electrode tabs (1141-2) provided on each of the other two first electrodes (1141) that are evenly close to the plurality of first electrodes (1141) overlap each other when projected perpendicularly to the xy plane.

[0202] In some embodiments, the second electrode arrangement (115) may be configured such that the second electrode tabs (1151-2) provided on each of the two second electrodes (1151) and the second electrode tabs (1151-2) provided on each of the other two second electrodes (1151) that are evenly close to the plurality of second electrodes (1151) overlap each other when projected perpendicularly to the xy plane.

[0203] The electrode tabs provided on the other two first electrodes (1141) and second electrodes (1151), which are each the evenly numbered closest to the two first electrodes (1141) and second electrodes (1151), are projected perpendicularly onto the xy plane and overlap each other, thereby making it easy to charge and discharge each cell.

[0204]

[0205] As described above, although embodiments of the present invention have been described in detail, a person skilled in the art to which the present invention pertains will be able to modify and implement the present invention in various ways without departing from the spirit and scope of the present invention as defined in the appended claims. Therefore, future modifications to the embodiments of the present invention will not depart from the technology of the present invention.

Claims

1. A stacking step of folding the separator in a zigzag shape by moving it back and forth left and right, and stacking a plurality of first electrodes and a plurality of second electrodes alternately between the separators to form a plurality of electrode assemblies; A separator cutting step of cutting the separator to a length capable of wrapping the plurality of electrode assemblies to provide an extra separator; A wrapping step of wrapping the plurality of electrode assemblies with the above extra separator; and The electrode assembly cutting step of cutting the separator located between the plurality of electrode assemblies to separate them into individual electrode assemblies; The above stacking step is, A step of stacking a type a first electrode having a type a first electrode tab among a plurality of first electrodes in a region corresponding to the individual electrode assembly; A step of stacking a type a second electrode having a type a second electrode tab among a plurality of second electrodes in a region corresponding to the individual electrode assembly; A step of stacking a b-type first electrode having a b-type first electrode tab at a position different from the a-type first electrode tab among a plurality of first electrodes in a region corresponding to the individual electrode assembly; and The method includes the step of stacking a b-type second electrode having a b-type second electrode tab at a position different from the a-type second electrode tab among a plurality of second electrodes in a region corresponding to the individual electrode assembly; A method for manufacturing a secondary battery in which the above-mentioned type a first electrode tab, the above-mentioned type a second electrode tab, the above-mentioned type b first electrode tab, and the above-mentioned type b second electrode tab are spaced apart from each other and do not overlap.

2. In Paragraph 1, The above stacking step is, A base membrane placement step in which the membrane is arranged in a first direction; A step of arranging a plurality of first electrodes spaced apart from each other on the base separator; A second direction separator placement step in which a separator connected to the base separator is folded on the base separator on which a plurality of mutually spaced first electrodes are arranged, and is arranged in a second direction opposite to the first direction; A step of arranging a plurality of second electrodes spaced apart from each other on the second direction separator above; A method for manufacturing a secondary battery comprising: a step of placing a first direction separator, wherein a separator connected to the second direction separator is folded on the second direction separator on which a plurality of spaced-apart second electrodes are arranged, and the first direction separator is arranged in a direction opposite to the second direction.

3. In Paragraph 1, A method for manufacturing a secondary battery, wherein the plurality of electrode assemblies are one of a monocell having different types of electrodes located at both ends and a bicell having the same type of electrodes located at both ends.

4. In Paragraph 1, In the above stacking step, A method for manufacturing a secondary battery characterized by configuring the images projected perpendicularly to the xy plane of the first electrode body portions of the plurality of first electrodes and the second electrode body portions of the plurality of second electrodes to be superimposed on each other.

5. In Paragraph 1, In the above stacking step, A method for manufacturing a secondary battery, characterized in that the plurality of first electrodes and the plurality of second electrodes are configured such that the tabs provided on each of the plurality of first electrodes and the tabs provided on each of the plurality of second electrodes are respectively disposed on the outer side of the corner portion excluding the folded corner portion of the separator.

6. In Paragraph 1, A method for manufacturing a secondary battery in which, after the electrode assembly cutting step, the individual electrode assembly is wrapped by the cut separator.

7. In Paragraph 1, In the above stacking step The above-mentioned type a first electrode and the above-mentioned type b first electrode are alternately stacked, A method for manufacturing a secondary battery by alternately stacking the above-mentioned type a second electrode and the above-mentioned type b second electrode.

8. In Paragraph 1, In the above stacking step, After the above-mentioned multiple first electrodes of type a are stacked, multiple first electrodes of type b are stacked, and A method for manufacturing a secondary battery in which a plurality of type a second electrodes are stacked, and then a plurality of type b second electrodes are stacked.

9. A stacking step of folding the separator in a zigzag shape by moving it back and forth left and right, and alternately arranging a plurality of first electrodes and a plurality of second electrodes between the separators to form a first electrode assembly and a second electrode assembly spaced apart from each other; A separator cutting step of providing an extra separator by cutting the separator to a length that can wrap the first electrode assembly and the second electrode assembly; A wrapping step of wrapping the first electrode assembly and the second electrode assembly with the above extra separator; and The electrode assembly cutting step of cutting the separator located between the first electrode assembly and the second electrode assembly to separate them into individual electrode assemblies; In the above stacking step, When the plurality of electrodes are stacked in the first electrode assembly region and the second electrode assembly region, respectively, the electrode tabs in the first electrode assembly region and the electrode tabs in the second electrode assembly region are stacked asymmetrically with respect to the cut surface of the separator, and The position of the electrode tab provided in the first electrode assembly is positioned on the outer side of the first side corner, which is one of the two side corners adjacent to the folded corner of the separator, and A method for manufacturing a secondary battery, wherein the position of the electrode tab provided in the second electrode assembly is disposed on the outer side of the second side corner, which is the other of the two side corners adjacent to the folded corner of the separator.

10. A stacking section that folds a separator in a zigzag shape by moving it back and forth left and right, and alternately arranges a plurality of first electrodes and a plurality of second electrodes between the separators to form a plurality of electrode assemblies; A separator cutting section that cuts the separator to a length capable of wrapping the plurality of electrode assemblies to provide an extra separator; A wrapping portion that wraps the plurality of electrode assemblies with the above extra separator; and The electrode assembly cutting unit for cutting the separator located between the plurality of electrode assemblies to separate them into individual electrode assemblies; The above stacked portion is, In a region corresponding to the individual electrode assembly above, a type a first electrode having a type a first electrode tab among a plurality of first electrodes is stacked, and In a region corresponding to the individual electrode assembly, a b-type first electrode having a b-type first electrode tab at a position different from the a-type first electrode tab among a plurality of first electrodes is stacked, and In a region corresponding to the individual electrode assembly above, a type a second electrode having a type a second electrode tab among a plurality of second electrodes is stacked, and In a region corresponding to the individual electrode assembly, a b-type second electrode having a b-type second electrode tab at a position different from the a-type second electrode tab among a plurality of second electrodes is stacked, and A secondary battery manufacturing apparatus configured such that the above-mentioned type a first electrode tab, the above-mentioned type a second electrode tab, the above-mentioned type b first electrode tab, and the above-mentioned type b second electrode tab are spaced apart from each other and do not overlap.

11. In Paragraph 10, The above stacked portion is, A separator table having a zigzag folded separator size capable of accommodating and arranging multiple electrodes; A membrane supply unit that supplies a membrane that folds into a zigzag shape by moving the membrane back and forth. A first electrode placement section for arranging a plurality of first electrodes spaced apart from each other between separators supplied while folding in the zigzag shape; and A second electrode placement section that arranges a plurality of second electrodes spaced apart from each other between separators supplied by folding in a zigzag manner after arranging a plurality of first electrodes; A secondary battery manufacturing device including 12. In Paragraph 11, A secondary battery manufacturing apparatus characterized by the fact that the first electrode placement portion and the second electrode placement portion are configured to position the first electrode body portions of the plurality of first electrodes and the second electrode body portions of the plurality of second electrodes such that images projected perpendicularly to the xy plane can be superimposed on each other.

13. In Paragraph 11, The first electrode placement section and the second electrode placement section above are A secondary battery manufacturing apparatus characterized by arranging the plurality of first electrodes and the plurality of second electrodes such that the tabs provided on each of the plurality of first electrodes and the tabs provided on each of the plurality of second electrodes are respectively arranged on the outer side of the corner portion excluding the folded corner portion of the separator.

14. In Paragraph 10, A secondary battery manufacturing apparatus configured such that, after the electrode assembly cutting part cuts the electrode assembly, the individual electrode assembly is wrapped by the cut separator.

15. In Paragraph 10, The above stacked part The above-mentioned type a first electrode and the above-mentioned type b first electrode are alternately stacked, A secondary battery manufacturing apparatus configured to alternately stack the above-mentioned type a second electrode and the above-mentioned type b second electrode.

16. In Paragraph 10, The above stacked portion is, After the above-mentioned multiple first electrodes of type a are stacked, multiple first electrodes of type b are stacked, and A secondary battery manufacturing apparatus configured such that a plurality of type a second electrodes are stacked, and then a plurality of type b second electrodes are stacked.

17. A stacking section that stacks a plurality of first electrodes and a plurality of second electrodes alternately arranged between the separators while reciprocating the separator left and right to fold it in a zigzag shape, thereby forming a first electrode assembly and a second electrode assembly spaced apart from each other; A separator cutting section that cuts the separator to a length capable of wrapping the first electrode assembly and the second electrode assembly to provide an extra separator; A wrapping portion that encloses the first electrode assembly and the second electrode assembly with the above extra separator; and The electrode assembly cutting unit for cutting the separator located between the first electrode assembly and the second electrode assembly to separate them into individual electrode assemblies; The above stacked portion is, When one of the plurality of electrodes is stacked in a first electrode assembly region and a second electrode assembly region, respectively, the electrode tabs in the first electrode assembly region and the electrode tabs in the second electrode assembly region are stacked asymmetrically with respect to the cut surface of the separator, and The position of the electrode tab provided in the first electrode assembly is positioned on the outer side of the first side corner, which is one of the two side corners adjacent to the folded corner of the separator, and A secondary battery manufacturing apparatus configured such that the position of the electrode tab provided in the second electrode assembly is positioned on the outer side of the second side corner, which is the other of the two side corners adjacent to the folded corner of the separator.

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