Calendering system, electrode manufacturing method using same, and electrode manufactured thereby

Abstract

A calendering system according to the present invention comprises: a calender apparatus for compressing a mixture including an active material and a binder, the calender apparatus comprising calender rolls each having an overlapping area positioned to overlap the mixture and a non-overlapping area positioned such that the overlap with the mixture is restricted; a pair of sensor devices for sensing the non-overlapping areas and the mixture having a pair of edges adjacent thereto; and a control unit for determining the thickness at the pair of edges of the mixture on the basis of the information sensed by the pair of sensor devices of the mixture and non-overlapping areas.

Description

Calendaring system, electrode manufacturing method performed thereby, and electrode manufactured thereby

[0001] Cross-citation with related applications

[0002] This application claims the benefit of priority from Korean Patent Application No. 10-2024-0059448, filed May 3, 2024, the entire contents of which are incorporated herein by reference.

[0003] Technology field

[0004] The present invention relates to a calendering system, a method for manufacturing an electrode using the same, and an electrode manufactured using the same. More specifically, the invention relates to a calendering system for compressing a mixture so that the thickness of the mixture contained in the electrode is uniform, a method for manufacturing an electrode using the same, and an electrode manufactured using the same.

[0005] Secondary batteries are used not only in small products such as digital cameras, P-DVDs, MP3 players, mobile phones, PDAs, portable game devices, power tools, and e-bikes, but also in large products requiring high output such as electric vehicles and hybrid vehicles, as well as in power storage devices that store surplus generated power or renewable energy and power storage devices for backup purposes.

[0006] Typically, secondary batteries are manufactured by applying electrode active material slurry to a positive electrode current collector and a negative electrode current collector to form an electrode active material layer, then manufacturing a positive electrode and a negative electrode through a drying and rolling process, and then laminating these on both sides of a separator to form an electrode assembly of a predetermined shape, and then housing the electrode assembly in a battery case, injecting electrolyte, and sealing the electrode assembly.

[0007] Meanwhile, during the drying process of the electrode active material slurry, the solvent contained in the slurry may evaporate, causing defects such as pinholes or cracks in the electrode active material layer formed on the current collector. In addition, since the inside and outside of the electrode active material slurry are not uniformly dried during the drying process, there is a concern that the powder floating phenomenon due to the difference in solvent evaporation rate may occur, i.e., the powder in the area that dries first may rise and form a gap with the area that dries relatively later, which may deteriorate the electrode quality.

[0008] To solve the above problem, a drying device capable of controlling the evaporation rate of the solvent so that the inside and outside of the electrode active material slurry can be dried evenly is being considered, but such drying devices are very expensive and require considerable cost and time to operate, which is disadvantageous in terms of manufacturing process.

[0009] On the other hand, the solvent typically used in electrode active material slurries is N-methyl-2-pyrrolidone (NMP). Its high boiling point necessitates high heat energy and a very long drying process for drying, making it highly unsuitable for mass production. Furthermore, NMP is toxic and harmful to living organisms, making it unfriendly to the environment.

[0010] Accordingly, there has been a recent trend of active research on dry electrodes that manufacture electrodes without using solvents. The dry electrode is generally manufactured by laminating a free-standing type dry electrode film manufactured in the form of a sheet containing a mixture of an active material, a binder, a conductive material, etc., onto a current collector. This dry electrode film includes a process of first mixing an electrode active material, a carbon material as a conductive material, and a fiberizable binder together using a blender or the like, then applying a shear force through a process such as kneading to fiberize the binder, and then calendering the obtained mixture into a film form to manufacture a free-standing film.

[0011] At this time, the dry electrode film needs to have a uniform thickness during the calendering process. If the thickness of the dry electrode film is not uniform, the generation of electricity in the electrodes formed through the dry electrode film may not be uniform. Furthermore, since the electrode thickness is not uniform, gaps may form in the electrode laminate formed by laminating them, which may cause a problem of reduced energy density per volume.

[0012] The present invention has been devised to solve the above problems, and the object of the present invention is to provide a calendering system for uniformly calendering a mixture so that the thickness of the electrode is uniform, a method for manufacturing an electrode performed thereby, and an electrode manufactured thereby.

[0013] The technical problems to be achieved in this document are not limited to the technical problems mentioned above, and other technical problems not mentioned can be clearly understood by a person having ordinary skill in the technical field to which the present disclosure belongs from the description below.

[0014] A calendering system according to one embodiment of the present invention comprises a calender device configured to compress a mixture containing an active material and a binder, the calender device including a calender roll having an overlapping region positioned to overlap with the mixture and a non-overlapping region positioned to limit overlap with the mixture, a pair of sensor devices configured to sense the mixture and the non-overlapping region, the non-overlapping region having a pair of edges adjacent to the non-overlapping region, and a control unit configured to determine a thickness at each of the pair of edges of the mixture based on information of the mixture and the non-overlapping region sensed by the pair of sensor devices.

[0015] The sensor device may include a laser profile measuring device.

[0016] The thickness at a pair of edges of the mixture can be defined as the distance from the sensor device to the non-overlapping region minus the distance to the edges of the mixture.

[0017] The control unit may be configured to determine whether the mixture has a constant thickness between the pair of edges based on thickness information at each of the pair of edges of the determined mixture.

[0018] The control unit may be configured to determine that the calendaring is normal if the difference between the thicknesses at each of a pair of edges of the determined mixture is within a predetermined range.

[0019] The control unit may be configured to control the calendar roll so as to reduce the difference in thickness when the difference between the thicknesses at each of a pair of edges of the judged mixture is greater than a predetermined range.

[0020] The calender roll may further include a moving device configured to move one end of the calender roll in the longitudinal direction or the other end positioned opposite the one end, and the control unit may be configured to control the moving device to move at least one of the one end or the other end of the calender roll when the difference between the thicknesses at each of a pair of edges of the determined mixture is greater than a predetermined range.

[0021] A pair of sensor devices may be positioned adjacent to the boundary between the non-overlapping and overlapping areas.

[0022] The calendar rolls may be provided in multiple numbers so that the mixture is moved and compressed between them, and a pair of sensor devices may be provided in multiple numbers so as to correspond to at least one of each of the plurality of calendar rolls.

[0023] A virtual plane including a rotation axis of each of a plurality of calendar rolls is defined, the plurality of calendar rolls include a first calendar roll and a second calendar roll adjacent to the first calendar roll, an overlapping area of ​​the second calendar roll is positioned on an opposite side of the virtual plane from the overlapping area of ​​the first calendar roll, and the plurality of pairs of sensor devices include a first pair of sensor devices for sensing the first calendar roll and a second pair of sensor devices for sensing the second calendar roll, and the second pair of sensor devices can be positioned on an opposite side of the virtual plane from the first pair of sensor devices.

[0024] The control unit can obtain information about the thickness of each mixture passing through the plurality of calendar rolls based on information obtained from each of the plurality of pairs of sensor devices.

[0025] The control unit can control the movement of the calendar rolls to reduce the gap between the adjacent pair of calendar rolls when the thickness of the mixture formed by the adjacent pair of calendar rolls exceeds a predetermined range.

[0026] The control unit can control the movement of the calendar rolls to widen the gap between the adjacent pair of calendar rolls when the thickness of the mixture formed by the adjacent pair of calendar rolls is below a predetermined range.

[0027] The control unit may determine that the edges of the mixture are damaged based on the thickness being 0 at each of a pair of edges of the determined mixture.

[0028] The control unit may be configured to measure the surface uniformity of the calender roll when the mixture is not overlapped on the calender roll. /

[0029] A method for manufacturing an electrode according to one embodiment of the present invention may include a preparation step of preparing a mixture including an active material and a binder, a compression step of compressing the mixture by a calender roll while the calender roll has an overlapping region positioned to overlap the mixture and a non-overlapping region positioned to limit overlap with the mixture, a sensing step of sensing the mixture and the non-overlapping region having a pair of edges adjacent to the non-overlapping region by a pair of sensor devices, and a judgment step of determining a thickness at each of the pair of edges of the mixture based on information of the mixture and the non-overlapping region sensed by the pair of sensor devices.

[0030] The sensor device may include a laser profile measuring device.

[0031] The judgment step may be performed to determine the thickness at a pair of edges of the mixture as the distance from the sensor device to the non-overlapping area minus the distance to the edges of the mixture.

[0032] The electrode manufacturing method may further include a control step of controlling the calendar roll to reduce the difference in thickness when the difference between the thicknesses of each of a pair of edges of the mixture determined in the determination step is greater than a predetermined range.

[0033] An electrode according to one embodiment of the present invention includes a mixture containing an active material and a binder and a current collector to which the mixture is bonded, and a widthwise thickness of the mixture may be uniform in one part and may increase in one part in the widthwise direction.

[0034] The calendaring system according to the present invention can determine whether there is a thickness difference between the two edges of the mixture by having a pair of sensor devices calculate the height difference between the two edges of the mixture and the calender roll.

[0035] The calendaring system according to the present invention can uniformly calendar the mixture so that the thickness of the electrode is uniform by controlling the position of the calendar roll based on the determination of whether there is a difference in thickness between the two edges of the mixture.

[0036] The calendaring system according to the present invention measures the thickness of a mixture in a non-contact manner, so that even if the thickness of the mixture is measured during the calendaring process, the quality of the mixture may not be deteriorated.

[0037] The calendaring system according to the present invention has a feedback system that uniformly controls the thickness of the mixture in real time by reflecting the difference in the thickness of the mixture determined during the calendaring process, thereby enabling the thickness of the mixture to be uniform quickly.

[0038] The calendaring system according to the present invention can easily reflect changes in the desired thickness of the mixture and produce a mixture having a desired thickness.

[0039] The calendaring system according to the present invention can easily detect damage at the edge of the mixture.

[0040] The calendaring system according to the present invention can easily determine the surface uniformity of the calendar roll.

[0041] The effects that can be obtained from the present invention are not limited to the effects mentioned above, and other effects not mentioned can be clearly understood by a person having ordinary skill in the art to which the present disclosure pertains from the description below.

[0042] FIG. 1 is an assembly drawing of a secondary battery showing an electrode assembly according to a first embodiment of the present invention assembled into a battery case.

[0043] Fig. 2 is a cross-sectional view of the electrode laminate illustrated in Fig. 1.

[0044] Fig. 3 is a flowchart showing a method for manufacturing the electrode laminate illustrated in Fig. 2.

[0045] Figure 4 is a conceptual diagram illustrating performing the calendaring step illustrated in Figure 3.

[0046] FIG. 5 is a perspective view illustrating a portion of the calendaring system illustrated in FIG. 4.

[0047] FIG. 6 is a perspective view showing part of the calendaring system illustrated in FIG. 5 from a different angle.

[0048] FIG. 7 is a plan view illustrating the calendar roll, mixture, and sensor device illustrated in FIG. 5.

[0049] FIG. 8 is a conceptual diagram illustrating the sensor device illustrated in FIG. 5 sensing a mixture and a calendar roll.

[0050] Figure 9 is a graph showing the results measured by Figure 8.

[0051] Figure 10 is a control block diagram of the calendaring system illustrated in Figure 5.

[0052] Figure 11 is a flowchart of the calendaring step performed by the control unit illustrated in Figure 10.

[0053] FIG. 12 is a perspective view showing the remaining portion of the calendaring system illustrated in FIG. 5.

[0054] Fig. 13 is a conceptual diagram for explaining position control of the calendar roll illustrated in Fig. 12.

[0055] Figure 14 is a conceptual diagram illustrating the calendar rolls illustrated in Figure 13 moving in a direction that brings them closer to each other.

[0056] Figure 15 is a conceptual diagram illustrating the calendar rolls illustrated in Figure 14 moving away from each other.

[0057] FIG. 16 is a plan view illustrating a sensor device according to a second embodiment of the present invention.

[0058] Fig. 17 is a plan view illustrating a sensor device according to a third embodiment of the present invention.

[0059] Figure 18 is a flowchart of a calendaring step according to the fourth embodiment of the present invention.

[0060] Figure 19 is a flowchart of a calendaring step according to the fifth embodiment of the present invention.

[0061] Figure 20 is a flowchart of a calendaring step according to the sixth embodiment of the present invention.

[0062] Hereinafter, with reference to the attached drawings, preferred embodiments of the present invention will be described in detail so that those skilled in the art can easily implement the invention. However, the present invention may be implemented in various different forms and is not limited or restricted by the following examples.

[0063] In order to clearly explain the present invention, a detailed description of a part that is irrelevant to the description or a related known technology that may unnecessarily obscure the gist of the present invention has been omitted, and when adding reference signs to components of each drawing in this specification, the same or similar reference signs are attached to the same or similar components throughout the specification.

[0064] In addition, terms and words used in this specification and claims should not be interpreted as limited to their usual or dictionary meanings, but should be interpreted as meanings and concepts that conform to the technical idea of ​​the present invention based on the principle that the inventor can appropriately define the concept of the term to explain his or her own invention in the best way.

[0065] It should be understood that the various embodiments and terms used in this document are not intended to limit the technical features described in this document to specific embodiments, but rather to include various modifications, equivalents, or substitutes of the embodiments.

[0066] In connection with the description of the drawings, similar reference numerals may be used for similar or related components.

[0067] The singular form of a noun corresponding to an item may include one or more of said items, unless the relevant context clearly indicates otherwise.

[0068] In this document, each of the phrases "A or B", "at least one of A and B", "at least one of A or B", "A, B, or C", "at least one of A, B, and C", and "at least one of A, B, or C" may include any one of the items listed together in that phrase, or all possible combinations thereof.

[0069] The term "and / or" includes any combination of a plurality of related described elements or any one of a plurality of related described elements.

[0070] Terms such as "first," "second," or "first" or "second" may be used simply to distinguish one component from another and do not qualify the components in any other respect (e.g., importance or order).

[0071] When a component (e.g., a first component) is referred to as being "coupled" or "connected" to another component (e.g., a second component), with or without the terms "functionally" or "communicatively," it means that the component can be connected to the other component directly (e.g., wired), wirelessly, or through a third component.

[0072] The terms "include" or "have" are intended to specify the presence of a feature, number, step, operation, component, part or combination thereof described in this document, but do not preclude the presence or addition of one or more other features, numbers, steps, operations, components, parts or combinations thereof.

[0073] When a component is said to be “connected,” “coupled,” “supported,” or “in contact with” another component, this includes not only cases where the components are directly connected, coupled, supported, or in contact, but also cases where the components are indirectly connected, coupled, supported, or in contact through a third component.

[0074] When we say that a component is "on" another component, this includes not only cases where the component is in contact with the other component, but also cases where there is another component between the two components.

[0075]

[0076] *53Meanwhile, the terms “upper and lower direction,” “lower side,” and “front and rear direction” used in the description below are defined based on the drawing, and the shape and position of each component are not limited by these terms.

[0077] Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings. For convenience, the following embodiments are divided into first and second embodiments, and the description of each embodiment may additionally describe other embodiments.

[0078] Example 1

[0079] FIG. 1 is an assembly diagram of a secondary battery, illustrating an electrode assembly according to a first embodiment of the present invention being assembled into a battery case. FIG. 2 is a cross-sectional view of the electrode laminate illustrated in FIG. 1. FIG. 3 is a flowchart illustrating a method for manufacturing the electrode laminate illustrated in FIG. 2.

[0080]

[0081] Referring to FIGS. 1 to 3, a secondary battery (B) according to a first embodiment of the present invention will be described.

[0082] As illustrated in FIG. 1, a secondary battery (B) for generating electricity may be provided. The secondary battery (B) may include an electrode assembly (EA) and / or a battery case (200) that accommodates the electrode assembly (EA). The type of the secondary battery (B) may be determined according to the shape or type of the battery case (200). For example, if the battery case (200) is cylindrical, it may be referred to as a cylindrical secondary battery (B), and if the battery case (200) is square, it may be referred to as a square secondary battery (B). If the battery case (200) is manufactured using a pouch film, the secondary battery (B) may be referred to as a pouch-type secondary battery (B). The drawings of the present disclosure and the following description are illustrated and described assuming that the secondary battery (B) is a pouch-type secondary battery (B). However, the idea of ​​the present invention can still be applied not only to the case where the secondary battery (B) is a pouch-type secondary battery (B), but also to the case where the secondary battery (B) is a cylindrical secondary battery (B) and a square secondary battery (B).

[0083] At this time, the electrode assembly (EA) may be an assembly including an electrode (100) described below, and components related to the electrode (100) assembled together. The electrode (100) may be a component including a reactant that reacts to generate electricity. The battery case (200) may protect the electrode assembly (EA) from impact by covering the electrode assembly (EA). The electrode assembly (EA) may require an electrolyte so that ions can move when it reacts to generate electricity, as described below. The battery case (200) may provide the electrolyte to the electrode assembly (EA) by accommodating the electrolyte together with the electrode assembly (EA). Furthermore, the electrolyte may generally mean a liquid electrolyte, but is not limited thereto, and the spirit of the present invention may also be applied to a solid electrolyte.

[0084] As illustrated in Fig. 1, the battery case (200) can be formed by a pouch film. As an example of the battery case (200), a battery case (200) of a pouch-type secondary battery (B) will be described.

[0085] A pouch film forming a pouch, which is an example of a battery case (200), may include a plurality of layers. The pouch film may include a sealant layer and a barrier layer positioned outside the sealant layer. It may include a surface protection layer positioned outside the barrier layer. At this time, the sealant layer may have a polymer material such as polypropylene, the barrier layer may have a metal material such as aluminum, and the surface protection layer may have a polymer material such as nylon. At this time, the fusion described below may mean that the facing pouch films are joined as the facing sealant layers are melted.

[0086] The pouch can be manufactured from a highly flexible material to accommodate the electrode assembly (EA) therein. A flexible pouch film can be drawn and molded using a punch (not shown) or the like, such that a portion thereof is stretched to form a receiving portion (210) having a pocket-shaped electrode receiving space (210S), thereby manufacturing the pouch. The pouch can accommodate and seal the electrode assembly (EA) such that a portion of the electrode lead (130) is exposed.

[0087] When forming a receiving portion (210) on a pouch film, only one receiving portion (210) may be formed on one pouch film, but the present invention is not limited thereto, and two receiving portions (210) may be drawn and formed adjacent to each other on one pouch film. Then, two receiving portions (210) that are adjacent to each other may be formed. Each receiving portion (210) may have the same depth, but the present invention is not limited thereto, and the depths of each receiving portion (210) may be different from each other. After accommodating an electrode assembly (EA) in one receiving portion (210), the pouch may be folded around an axis so that another receiving portion (210) faces the receiving portion (210). Accordingly, another receiving portion (210) may accommodate the electrode assembly (EA) from the upper side. Since two receiving portions (210) receive one electrode assembly (EA), an electrode assembly (EA) having a thicker thickness can be received than when there is only one receiving portion (210). In addition, since the pouch is folded, each side portion (220) is integrally connected to form a folding portion (223), so that the number of sides to be sealed can be reduced when performing a sealing process later. Accordingly, the process speed can be improved and the number of sealing processes can be reduced. For convenience of explanation, the battery case (200) described below is described assuming that two receiving portions (210) are formed on one pouch film.

[0088] The side section (220) may include a lead sealing section (221) configured to be positioned corresponding to the electrode lead (130) and a degas section (222) connected to the lead sealing section (221). First, the lead sealing section (221) may be sealed by fusion. Thereafter, an electrolyte may be injected into the electrode receiving space (210S) through the degas section (222) that is not yet sealed, and the degas section (222) may be sealed by fusion. Thereafter, an activation process may be performed, and when the gas generated through the activation process moves into the degas section (222), a degassing process for removing the remaining gas may be performed. After the degas section (222) is sealed again, a trimming process may be performed to cut unnecessary portions so that the degas section (222) has a predetermined width. Thereafter, the degas portion (222) can be folded to reduce the width to form a folding portion (223).

[0089] As illustrated in FIG. 2, the electrode assembly (EA) can be formed by alternately stacking electrodes (100) and separators (140). The electrode (100) can be manufactured by applying a mixture (110) containing an active material (111), a binder (112), a conductive material (113), etc., to a current collector (120). Depending on the type of the active material (111), the electrode (100) can be a positive electrode (100) or a negative electrode (100). The positive electrode (100) and the negative electrode (100) can interact with each other to form electricity. More specifically, for example, the active material (111) included in the positive electrode (100) can include lithium, and the active material (111) included in the negative electrode (100) can include graphite. Lithium ions can move to the positive electrode (100) or the negative electrode (100) depending on the charging or discharging of the secondary battery (B), and electricity can be generated during this process. The configuration of the electrode assembly (EA) is described in more detail below.

[0090] The electrode (100) may include a current collector (120) and a mixture (110) applied or combined to the current collector (120). For example, as illustrated in FIG. 2, the mixture (110) may be applied to both sides of the current collector (120). Here, the current collector (120) may be, for example, a thin metal. The type of metal may vary depending on the polarity of the electrode (100). As illustrated in FIG. 2, for example, lithium may move between the positive electrode mixture (110a) and the negative electrode mixture (110b) facing each other with a separator (140) therebetween, and electricity may be generated. At this time, the separator (140) may be configured to allow lithium to pass through. The generated electricity may be transferred through the current collector (120). The current collector (120) may have electrode tabs (121) formed at ends thereof where no active material (111) is positioned.

[0091] A plurality of electrodes (100) can be alternately stacked with a separator (140) to form an electrode stack (ES). An electrode lead (130) can be provided to gather the respective electrode tabs (121) of the plurality of electrodes (100) included in the electrode stack (ES). Electrode tabs (121) having the same polarity can be gathered, and the electrode leads (130) can be joined to portions of the gathered electrode tabs (121). For example, as illustrated in FIG. 1, a plurality of electrode tabs (121) having positive poles can be positioned forward, a plurality of electrode tabs (121) having negative poles can be positioned rearward, and the electrode tabs (121) having positive poles can be welded to join them, and then the electrode leads (130) can be joined to the ends of the welded electrode tabs (121) by welding or the like. The electrode tabs (121) having negative poles can also be formed through the same process as the electrode tabs (121) having positive poles. As described above, the generated electricity can be transferred from the electrode assembly (EA) to the outside of the electrode assembly (EA) through the electrode tab (121) and the electrode lead (130). The electrode lead (130) may have one end connected to the electrode tab (121) and the other end protruding outward from the battery case (200). Accordingly, a component requiring electricity can obtain electricity from the secondary battery (B) by making contact with the electrode lead (130).

[0092] As illustrated in FIG. 1, the electrode assembly (EA) may include an insulating portion (131) surrounding a portion of the electrode lead (130). The insulating portion (131) may be positioned to correspond to a position where the side portion (220) described below is fused. When the opposing side portions (220) are fused to each other, the insulating portion (131) may be positioned between the side portions (220) to adhere the electrode lead (130) to the pouch. In addition, the insulating portion (131) may prevent electricity generated from the electrode assembly (EA) from flowing to the pouch through the electrode lead (130) and maintain the sealing of the pouch. Therefore, the insulating portion (131) may be made of a non-conductive material that does not conduct electricity well. For example, the insulating portion (131) may be an insulating tape that is easy to attach to the electrode lead (130) and has a relatively thin thickness. However, without limitation thereto, various materials may be used as long as the electrode lead (130) can be insulated.

[0093] As described above, when the mixture (110) contains a solvent, the solvent needs to be evaporated. In the process of drying the mixture (110), as the solvent contained in the mixture (110) evaporates, defects such as pinholes or cracks may be induced in the mixture (110) formed on the current collector (120). In addition, since the inside and outside of the electrode (100) active material (111) slurry are not uniformly dried during the drying process, there is a concern that the quality of the electrode (100) may deteriorate due to a powder floating phenomenon caused by a difference in the solvent evaporation rate, that is, powders in the area that dries first rise and form a gap with the area that dries relatively later.

[0094] To solve the above problem, a drying device capable of controlling the evaporation rate of the solvent so that the inside and outside of the electrode (100) active material (111) slurry can be uniformly dried is being considered, but such drying devices are very expensive and require considerable cost and time to operate, which is disadvantageous in terms of manufacturing process.

[0095] On the other hand, the solvent included in the mixture (110) containing a conventional solvent is N-methyl-2-pyrrolidone (NMP), which has a high boiling point, requiring high heat energy and a very long drying process to dry, making it very disadvantageous for mass production. In addition, N-methyl-2-pyrrolidone (NMP) is a toxic substance and is harmful to living organisms, making it unfriendly.

[0096] To address this, a dry electrode (100) manufactured using an active material (111) that does not use a solvent may be provided. The electrode (100) described in the present disclosure may be viewed as a dry electrode (100) manufactured using a mixture (110) that does not use a solvent. Alternatively, it may be applied to an electrode (100) that processes a mixture (110) using the kneading process described below.

[0097] A dry electrode (100) can be manufactured through the following processes, as a representative example. As illustrated in FIG. 3, a dry electrode (100) can be manufactured through a pre-mixing step (S10), a kneading step (S20), a calendaring step (S30), a lamination step (S40), and / or a stacking step (S50).

[0098] First, a mixture (110) including an active material (111), a conductive material (113), and / or a binder (112) may be prepared to form a dry electrode (100). In particular, the binder (112) may form fibers as its crystallized structure is destroyed. The fibers formed by the destruction of the binder (112) may bind the active materials (111) to each other. The degree of destruction of the crystallized structure of the binder (112) may be explained by the degree of crystallinity or the degree of fiberization. Here, the degree of crystallinity of the binder (112) may refer to the proportion of the binder (112) having a crystallized structure among the entire binder (112), and the degree of fiberization of the binder (112) may refer to the proportion of the binder (112) that has been fiberized among the entire binder (112).

[0099] The pre-mixing step (S10) may be a step for evenly mixing the mixture (110). For example, if the active material (111), conductive material (113), and / or binder (112) are provided in powder form, the powder must be evenly mixed to prevent quality differences depending on the location of the completed electrode (100). In the pre-mixing step (S10), a portion of the binder (112) may be fiberized.

[0100] If the fiberization of the binder (112) does not occur in the pre-mixing step (S10), it may be difficult to knead the mixture (110) in the kneading step (S20) described later. The mixture (110) may be prepared in a powder state before performing the pre-mixing step (S10). This is because the active material (111), binder (112), and conductive material (113) mentioned above are generally prepared in a powder state. Since the mixture (110) for making a dry electrode does not contain a solvent, there may be no factor that causes the mixture (110) to clump together. If the kneading step (S20) is performed on the mixture (110) in this powder state, the kneading step (S20) applies a shear force to the mixture (110) to break the crystals of the binder (112) and cause fiberization. However, when a shear force is applied to the mixture (110), the particles of the powder mixture (110) may only move separately from each other, and the crystals of the binder (112) may not be broken easily. If the fiberization of the binder (112) has partially progressed in the pre-mixing step (S10), the mixture (110) may stick together, for example, in a clay-like state. In this case, when a shear force is applied to the mixture (100), the binder (112) may not move due to the applied shear force, but the crystals may break and fiberization may occur. Therefore, in order for the mixture (110) to be kneaded, a portion of the binder needs to be fiberized.

[0101] The kneading step (S20) may refer to a step of fiberizing the binder (112) by destroying the crystallized structure of the binder (112) mentioned above, as illustrated in FIG. 4. Here, kneading may refer to applying pressure to the structure. The degree of fiberization of the binder (112) determined in the kneading step may determine the mechanical strength of the active material (111). It may be desirable for the binder (112) to have a crystallinity or fiberization degree within a predetermined range. This is because if the fiberization of the binder (112) is too little, it may be difficult to bind the mixture (110) to each other, and if the fiberization of the binder (112) is too much, the active material (111) may be easily broken. The active material (111) that has completed the kneading step may have a form of dough that is clumped together like clay. In particular, based on FIG. 4, the circular crystallized binder (112) can be transformed into a mesh-shaped fiberized binder (112a) by the crystal being disintegrated.

[0102] The calendering step (S30) may refer to a step of bonding the active material (111) that has completed the kneading step (S20) to the current collector (120). For example, the current collector (120) and the active material (111) may be placed between rollers and pressed to bond the kneaded active material (111) to the current collector (120). In the calendering step (S20), the mixture (110) needs to be spread out flat with a uniform thickness. If the thickness of the mixture (110) is not uniform, a problem of uneven electricity generation may occur in the electrode (100) formed by the mixture (110). Furthermore, since the thickness of the electrode (100) is not uniform, a gap may be formed in the electrode laminate (ES) formed by stacking them, which may cause a problem of reduced energy density per volume. This calendering step (S30) will be described in more detail below with reference to other drawings.

[0103] The lamination step (S40) may be a step of manufacturing a semi-finished product by laminating an electrode (100) and a separator (140) in which a mixture (110) is combined on a current collector (120).

[0104] The stacking step (S50) may be a step of forming a completed electrode laminate (ES) by stacking semi-finished products manufactured in the lamination step (S40).

[0105] At this time, as previously mentioned, the calendaring step (S30) may be an important step in determining the quality of the electrode (100). This will be described in more detail below with reference to the drawings.

[0106] Figure 4 is a conceptual diagram illustrating the performance of the calendaring step illustrated in Figure 3. In particular, Figure 4 is illustrated as looking at the side of the calendar roll (300).

[0107] Referring to FIG. 4, a calendaring system (1) according to a first embodiment of the present invention is schematically described.

[0108] As illustrated in FIG. 4, a calendaring system (1) may be provided to perform the calendaring step (S30). The calendaring system (1) may be a collection of devices for performing the calendaring step (S30). However, the spirit of the present invention is not limited to a calendaring system (1) defined as a collection of multiple devices, but may also be applied to a calendaring system (1) provided as a single device. For convenience of explanation, the description of the first embodiment assumes that the calendaring system (1) includes multiple devices.

[0109] The calendaring system (1) may include a calendar roll (300) capable of compressing a mixture (110). The calendar roll (300) may have a roller shape, for example, as illustrated in FIG. 4. However, despite its name, the calendar roll (300) may be interpreted as including any device that compresses the mixture (110). For example, the calendar rolls (300) illustrated in FIG. 4 are provided in multiple numbers, such that the mixture (110) is inserted between adjacent calendar rolls (300), and the inserted mixture (110) is moved under pressure by receiving pressure from each of the adjacent calendar rolls (300) as the calendar rolls (300) rotate. In the present disclosure, for the convenience of explanation, it will be assumed and described that the calendar rolls (300) are driven in this manner, but the present invention is not limited thereto. For example, the calendar roll (300) may be provided singly and positioned with a flat plate and a constant gap, and the mixture (110) may be positioned in the gap formed between the flat plate and the calendar roll (300), so that the mixture (110) positioned in the gap may be pressurized, compressed, and moved by the calendar roll (300). Alternatively, the calendaring system (1) may be viewed as not implementing a method of pressing the mixture (110) by a roll, but as pressing the mixture (110) by a press device (not shown). In this way, the calendaring system (1) or the calendar roll (300) to which the idea of ​​the present invention can be applied is not limited to that shown in the drawing, and any thing capable of performing calendaring may be applied without limitation. However, for convenience of explanation, it is assumed and explained that the calendar roll (300) is configured to compress the mixture (110) by allowing the mixture (110) to pass through the space between adjacent calendar rolls (300).

[0110] In other words, as mentioned above, the calender roll (300) may be provided in multiples. For example, as illustrated in FIG. 4, the calender roll (300) may be provided in fours. The multiple calender rolls (300) may include a first calender roll (300a) and a second calender roll (300b) positioned close to the first calender roll (300a). The first calender roll (300a) and the second calender roll (300b) may be configured to rotate in opposite directions so that the mixture (110) positioned between the first calender roll (300a) and the second calender roll (300b) is compressed and moved. For example, as shown in FIG. 4, when a mixture (110) is provided on the upper side between the first calendar roll (300a) and the second calendar roll (300b), the first calendar roll (300a) rotates clockwise and the second calendar roll (300b) rotates counterclockwise, so that the mixture (110) can pass between the first calendar roll (300a) and the second calendar roll (300b) and move downward.

[0111] Additionally, the mixture (110) provided to the calendaring system (1) may be a mixture (110) that has completed the kneading step (S20). Accordingly, the mixture (110) may be prepared as a dough rather than a powder. Accordingly, the mixture (110) that has passed through the first calendar roll (300a) and the second calendar roll (300b) may not fall directly downward as shown in FIG. 4, but may be adhered to the surface of the second calendar roll (300b) and may move toward the space between the second calendar roll (300b) and another calendar roll (300).

[0112] At this time, if only the first calendar roll (300a) and the second calendar roll (300b) are provided, calendering or pressing can be performed once. If, as illustrated in FIG. 4, four calendar rolls (300) are provided, calendering or pressing can be performed three times. By repeated calendering or pressing, the mixture (110) can be easily pressed to a desired thickness. For example, calendering or pressing can be performed first to a thick thickness by the calendar roll (300) located at the front, and then to a thinner thickness by the calendar roll (300) located at the rear.

[0113] While the calendaring system (1) is performing calendaring or pressing, the widthwise thickness of the calendared mixture (110) may not be constant. If the widthwise thickness of the mixture (110) is not constant, the thickness of the electrode (100) formed thereby may also not be constant, which may cause a problem. Furthermore, if the widthwise thickness of the mixture (110) is not constant, the electricity generated by the mixture (110) may not be uniform in the widthwise direction. To solve this problem, as described below, it is necessary to first sense the thickness of the mixture (110). This will be described in more detail with reference to the drawings below.

[0114] Fig. 5 is a perspective view illustrating a portion of the calendaring system (1) illustrated in Fig. 4. Fig. 6 is a perspective view illustrating a portion of the calendaring system (1) illustrated in Fig. 5 from a different angle. Fig. 7 is a plan view illustrating the calendar roll (300), the mixture (110), and the sensor device (400) illustrated in Fig. 5. Fig. 8 is a conceptual diagram illustrating the sensor device (400) illustrated in Fig. 5 sensing the mixture (110) and the calendar roll (300). Fig. 9 is a graph illustrating the results measured by Fig. 8.

[0115] Referring to FIGS. 5 to 9, the calendaring system (1) according to the first embodiment of the present invention will be described in more detail.

[0116] The aforementioned calendar roll (300) may be included in a calendar device (CA). The calendar device (CA) may be configured to compress a mixture (110) containing an active material and a binder. The calendar device (CA) may be a concept that includes a device for moving the calendar roll (300), which will be described below with reference to FIG. 12 and the like. Furthermore, the calendar device (CA) may be included in a calendaring system (1). The calendaring system (1) may include the calendar device (CA) and a sensor device (400) described below.

[0117] The calendar roll (300) may include a roll body (310) configured to be adjacent to the mixture (110), as illustrated in FIGS. 5 and 6. The roll body (310) may have a substantially cylindrical shape. The calendar roll (300) may include a roll shaft (320) extending from a longitudinal end of the roll body (310). The roll shafts (320) may be provided as a pair, extending from each end of the roll body (310). The pair of roll shafts (320) may be rotated by receiving driving force from a driving unit (not shown) that may be provided as a motor or an actuator. At this time, the roll body (310) may be rotated according to the rotation of the roll shaft (320). For reference, the roll shaft (320) and the roll body (310) may be formed integrally, or may be formed separately and then coupled.

[0118] As illustrated in FIGS. 5 and 6, the calendar roll (300) may have an overlapping region (301A) positioned to overlap with the mixture (110) and a non-overlapping region (302A) positioned to limit overlap with the mixture (110). More specifically, the overlapping region (301A) and the non-overlapping region (302A) may be formed in the roll body (310).

[0119] As illustrated in FIGS. 5 and 6, the calendaring system (1) may include a mixture (110) having a pair of edges adjacent to a non-overlapping region (302A) and a pair of sensor devices (400) configured to sense the non-overlapping region (302A). In particular, as illustrated in FIG. 7, the pair of sensor devices (400) may be positioned to sense a pair of edges positioned in the width direction of the mixture (110), respectively. Furthermore, the pair of sensor devices (400) may not only sense the edges of the mixture (110), but may also sense the calendar roll (300).

[0120] At this time, the calendaring system (1) may include a control unit (900) configured to determine the thickness of each of a pair of edges of the mixture (110) based on information of the mixture (110) and the non-overlapping area (302A) sensed by a pair of sensor devices (400), as illustrated in FIG. 10.

[0121] More specifically, the sensor device (400) may be a laser profile measuring device. The laser profile measuring device may be a device that can measure the distance between an object to be measured by a laser and the laser profile measuring device. For convenience of explanation, the following description assumes that the sensor device (400) includes a laser profile measuring device, but the spirit of the present invention may be applied to other sensor devices (400) other than a laser profile measuring device. For example, it may be applied to other embodiments described in FIGS. 16 and 17, or to a device that senses heat by measuring infrared rays, etc. For example, the thickness of the mixture (110) may be determined using the temperature in the calendar roll (300) and the temperature level in the mixture (110).

[0122] When the sensor device (400) is a laser profile measuring device, as illustrated in FIG. 8, the distance (D1) from the sensor device (400) to the mixture (110) can be measured. Furthermore, the distance (D2) from the sensor device (400) to the surface of the calendar roll (300) can be measured. At this time, the distance from the sensor device (400) to the surface of the calendar roll (300) can be obtained by measuring the distance (D2) from the sensor device (400) to the non-overlapping area (302A). Accordingly, as illustrated in FIG. 9, the thickness at a pair of edges of the mixture (110) can be defined as the distance (D2) from the sensor device (400) to the non-overlapping area (302A) minus the distance (D1) to the edge of the mixture (110).

[0123] At this time, a pair of sensor devices (400) may be positioned adjacent to the boundary of the non-overlapping area (302A) and the overlapping area (301A), as illustrated in FIG. 7. Each sensor device (400) needs to be able to measure both the distance from the sensor device (400) to the mixture (110) and the distance from the sensor device (400) to the surface of the calender roll (300). If separate sensor devices (400) are to be used for each measurement, double the number of sensor devices (400) will be used, resulting in an economic loss. To solve this problem, the sensor devices (400) may be positioned adjacent to the edge of the mixture (110), so that the distance to the mixture (110) and the distance to the surface of the calender roll (300) can be measured with one sensor device (400). However, if the distance to the mixture (110) and the distance to the surface of the calendar roll (300) are not to be measured with one sensor device (400), the sensor device (400) may not necessarily need to be positioned adjacent to the edge of the mixture (110).

[0124] At this time, the control unit (900) may be configured to determine whether the thickness of the mixture (110) is constant between the pair of edges based on the thickness information at each of the pair of edges of the determined mixture (110). In other words, the control unit (900) may obtain information about the thickness of the mixture (110) at each of the pair of edges of the mixture (110), as illustrated in FIG. 9. If the thickness of the mixture (110) at each of the edges of the mixture (110) matches, it may be determined that the thickness of the mixture (110) is constant in the width direction. If the thickness of the mixture (110) at each of the edges of the mixture (110) differs, it may be determined that the thickness of the mixture (110) changes between the two edges, and that the thickness of the mixture (110) is not constant in the width direction. At this time, it may be determined that the thickness of the mixture (110) located between the two edges of the mixture (110) changes linearly. This may be because, in the case of a device that moves the calendar roll (300) illustrated in Fig. 12, it is difficult for the thickness of the mixture (110) to change abruptly in the width direction.

[0125] In other words, the above is as follows. The control unit (900) may be configured to determine that the calendering is normal if the difference between the thicknesses of each of a pair of edges of the determined mixture (110) is within a predetermined range. Furthermore, the control unit (900) may be configured to control the calender roll (300) to reduce the thickness difference if the difference between the thicknesses of each of a pair of edges of the determined mixture (110) is greater than a predetermined range. The fact that the calender roll (300) is controlled to keep the thickness of the mixture (110) constant will be described in more detail in the description with reference to FIG. 12, etc.

[0126] At this time, as illustrated in FIG. 6, the calender rolls (300) may be provided in multiple numbers so that the mixture (110) is moved and compressed between them. Furthermore, a pair of sensor devices (400) may be provided in multiple numbers so as to correspond to at least one of the plurality of calender rolls (300). Accordingly, thickness information of the mixture (110) in each of the plurality of calender rolls (300) can be acquired. In other words, the control unit (900) can acquire information about the thickness of each of the mixtures (110) passing through the plurality of calender rolls (300) based on the information acquired from each of the plurality of pairs of sensor devices (400). Since the thickness of the mixture (110) can be adjusted at multiple points, the thickness of the mixture (110) can be controlled more precisely.

[0127] At this time, the positions of the plurality of pairs of sensor devices (400) can be defined as follows. First, a virtual plane including the rotation axis of each of the plurality of calendar rolls (300) can be defined. As mentioned above, the plurality of calendar rolls (300) can include a first calendar roll (300a) and a second calendar roll (300b) adjacent to the first calendar roll (300a). As illustrated in FIG. 6, the overlapping area (301A) of the second calendar roll (300b) can be positioned on the opposite side of the virtual plane from the overlapping area (301A) of the first calendar roll (300a). At this time, the plurality of pairs of sensor devices (400) can include a first pair of sensor devices (400a) for sensing the first calendar roll (300a) and a second pair of sensor devices (400b) for sensing the second calendar roll (300b). The second pair of sensor devices (400b) may be positioned on opposite sides of the virtual plane from the first pair of sensor devices (400a). In other words, the plurality of pairs of sensor devices (400) may be arranged in a zigzag pattern with respect to the plurality of calendar rolls (300), respectively.

[0128] To summarize the above once again, the calendaring system (1) can measure the thickness of edges positioned on opposite sides in the width direction of the mixture (110) in order to measure the thickness of the mixture (110) pressed by the calendar roll (300). The thickness can be measured by measuring the distance from the sensor device (400) to the mixture (110) and the distance from the sensor device (400) to the surface of the calendar roll (300), and utilizing the difference between the two distance values. Whether there is a difference in the width direction thickness of the mixture (110) can be determined by whether the difference in the thickness at the two edges of the mixture (110) is the same or different. If there is a difference in the width direction thickness of the mixture (110), the calendar roll (300) can be moved to control the difference in thickness to be reduced.

[0129] Below, the control of the control unit (900) that performs the above control is described in more detail.

[0130] Fig. 10 is a control block diagram of the calendaring system (1) illustrated in Fig. 5. Fig. 11 is a flowchart of the calendaring steps performed by the control unit (900) illustrated in Fig. 10.

[0131] Referring to FIGS. 10 and 11, a control method of a calendaring system (1) according to the first embodiment of the present invention will be described.

[0132] As illustrated in FIG. 10, the calendaring system (1) may include a control unit (900). The control unit (900) may be configured to command other components to be controlled. More specifically, the control unit (900) may be configured to control the driving device (500) based on information acquired from the sensor device (400).

[0133] The control unit (900) may include a memory (920). The memory (920) may include a volatile memory (920) such as a static random access memory (S-RAM) or a dynamic random access memory (D-RAM) for temporarily storing data. In addition, the memory (920) may include a non-volatile memory (920) such as a read only memory (ROM), an erasable programmable read only memory (EPROM), or an electrically erasable programmable read only memory (EEPROM) for storing data for a long period of time.

[0134] The control unit (900) may include a processor (910). The processor (910) may generate control signals for controlling the operation of the driving device (500), shaft, and / or cam based on instructions, applications, data, and / or programs stored in the memory (920). The processor (910) may be hardware and include logic circuits and arithmetic circuits. The processor (910) may process data according to programs and / or instructions provided from the memory (920) and generate control signals according to the processing results. The memory (920) and the processor (910) may be implemented as a single control circuit or as multiple circuits. For example, the processor (910) may be implemented as a Central Processing Unit (CPU), an application processor (AP), or a microprocessor (910).

[0135] The program described above may include program(s) implemented in the form of at least one of BIOS, device driver, operating system, firmware, platform, and application program. In one embodiment, the application program may be pre-installed or stored in the needing device or the needing system during the manufacturing of the needing device or the needing system, or may be installed in the needing device or the needing system based on data received from an external source at the time of subsequent use. The data of the application program may also be downloaded to the needing device or the needing system from an external server, such as an application market (app store). Such an external server is an example of the computer program product of the present invention, but is not limited thereto.

[0136] The control unit (900) can control the driving device (500) described below based on information obtained from the sensor device (400). By controlling the driving device (500), the calendar roll (300) can be moved, and accordingly, the gap between the calendar rolls (300) can be adjusted. This will be described in more detail in the description with reference to FIG. 12, etc.

[0137] The control unit (900) can perform control such as the flowchart illustrated in FIG. 11. However, the control that the control unit (900) can perform is not limited to that illustrated in FIG. 11. Furthermore, the control unit (900) according to the first embodiment of the present invention can control other components included in the calendaring system (1) to perform the electrode (100) manufacturing method. The electrode (100) manufacturing method in the present disclosure can refer to an electrode (100) manufacturing method for manufacturing a mixture (110) or electrode (100) having a constant thickness.

[0138] As illustrated in FIG. 11, the method for manufacturing an electrode (100) may include a preparation step (S100) of preparing a mixture (110) including an active material and a binder. The method for manufacturing an electrode (100) may include a pressing step (S200) of pressing the mixture (110) by the calender roll (300) while the calender roll (300) has an overlapping area (301A) positioned to overlap with the mixture (110) and a non-overlapping area (302A) positioned to limit overlap with the mixture (110). The method for manufacturing an electrode (100) may include a sensing step (S300) of sensing the mixture (110) and the non-overlapping area (302A) by a pair of sensor devices (400) having a pair of edges adjacent to the non-overlapping area (302A). Based on the information of the mixture (110) sensed by a pair of sensor devices (400) and the non-overlapping area (302A), a determination step (S400) for determining the thickness of each of a pair of edges of the mixture (110) may be included. After determining the thickness of the mixture (110), it is determined whether the difference between the thicknesses of each of a pair of edges of the mixture (110) determined in the determination step (S400) is within a predetermined range. If the difference in thickness of each edge is within the predetermined range, it is determined that the calendering is performed normally and the above adjustment process is completed. If the difference in thickness of each edge exceeds the predetermined range, a control step (S600) for controlling the calender roll (300) to reduce the thickness difference may be performed. Here, the above description assumes and describes that the calendering system (1) is controlled so that there is no thickness difference at both edges of the mixture (110), but in reality, it is difficult for there to be no thickness difference. Accordingly, by allowing a thickness difference that does not significantly cause a difference in quality, the control unit (900) can control the width direction thickness of the mixture (110) to not be less than the thickness difference.

[0139] This control can be performed during calendaring based on information obtained in real time by the sensor device (400). The electrode (100) manufacturing step can be performed by a feedback system, so that an optimized value can be found during the step. Accordingly, the time required to control the electrode (100) to have an appropriate thickness can be shortened, enabling a rapid process.

[0140] Below, a method for controlling the calendering thickness of a mixture (110) is described in detail. The method below describes in detail a method for controlling the thickness of a mixture (110) by controlling the position of a calender roll (300).

[0141] Fig. 12 is a perspective view including the remaining part of the calendaring system (1) illustrated in Fig. 5. Fig. 13 is a conceptual diagram for explaining the position control of the calendar roll (300) illustrated in Fig. 12. Fig. 14 is a conceptual diagram illustrating the calendar rolls (300) illustrated in Fig. 13 moving in a direction toward each other. Fig. 15 is a conceptual diagram illustrating the calendar rolls (300) illustrated in Fig. 14 moving in a direction away from each other.

[0142] Referring to FIGS. 12 to 15, a calendar device (CA) capable of controlling a calendar roll (300) according to the first embodiment of the present disclosure will be described.

[0143] As illustrated in FIG. 12, the calendar device (CA) may include a coupling member (330) coupled to the calendar roll (300). The coupling member (330) may be coupled to an end of the calendar roll (300), i.e., a roll shaft (320). At this time, the coupling member (330) may be coupled to the roll shaft (320) so that the roll shaft (320) can rotate. For example, the roll shaft (320) and the coupling member (330) may be coupled by a bearing or the like. Accordingly, while the roll shaft (320) rotates and the calendar roll (300) rotates, the roll shaft (320) can be moved by moving the coupling member (330).

[0144] The coupling members (330) may be provided in pairs to be coupled to both ends of the calendar roll (300). Each coupling member (330) may be coupled to each roll shaft (320). That is, two coupling members (330) may be coupled to one calendar roll (300). The coupling members (330) may be provided in multiples to correspond to multiple calendar rolls (300). In other words, one pair of coupling members (330) may be provided to correspond to one calendar roll (300), and multiple pairs of coupling members (330) may be provided to correspond to multiple calendar rolls (300).

[0145] The calendar device (CA) may include a coupling member guide (340) to guide a plurality of coupling members (330) positioned on the same side among a plurality of pairs of coupling members (330). The coupling member guide (340) may be formed so that a space having an opening is formed on one side. As illustrated in FIG. 12, the coupling member guide (340) may have a shape of a rotated “U”. The space formed by the coupling member guide (340) has a width corresponding to the height of the coupling members (330) and may extend in a direction in which the plurality of coupling members (330) are arranged. Accordingly, the coupling members (330) are restricted from moving in the height direction of the coupling members (330) by the coupling member guide (340), and may be moved in the direction in which the plurality of coupling members (330) are arranged by the coupling member guide (340). However, the joining member guide (340) to which the idea of ​​the present invention can be applied is not limited thereto, and the joining member guide (340) may have a shape other than the shape illustrated in FIG. 12. For example, the joining member guide (340) may have a rail shape. The joining member (330) may have a groove or a protrusion, and the joining member guide (340) may have a corresponding protrusion or groove to guide the movement of the joining member (330). Alternatively, the joining member guide (340) may not only limit the movement of the joining member (330) in the up-and-down direction as illustrated in FIG. 12, but may also limit the movement of the joining member (330) in the front-back direction.

[0146] The two ends of the calendar roll (300) can be moved according to the movement of the joining member (330). At this time, the calendar device (CA) may further include a moving device (351, 352) configured to move one end of the calendar roll (300) in the longitudinal direction or the other end located on the opposite side of the one end. More specifically, the moving device (351, 352) can move one end or the other end of the calendar roll (300) by moving the joining member (330). At this time, the control unit (900) may be configured to control the moving device (351, 352) to move at least one of the one end or the other end of the calendar roll (300) when the difference between the thicknesses of each of a pair of edges of the determined mixture (110) is greater than a predetermined range. More specifically, as the moving device (351, 352) moves, the coupling member (330) can move, and as the coupling member (330) moves, the calendar roll (300) can move.

[0147] At this time, the moving devices (351, 352) may be connected to a driving device (500) configured to be controlled by the control unit (900) in advance. The driving device (500) may be configured to provide driving force so that the moving devices (351, 352) are driven. The driving device (500) may be connected to the first moving device (351) and the second moving device (352) described below. Here, the driving device (500) may be an actuator, a motor, a hydraulic device, or the like.

[0148] The moving device (351, 352) may include a first moving device (351) configured to move a connecting member (330) located at the outermost side among a plurality of connecting members (330) and a second moving device (352) located between the plurality of connecting members (330). The first moving device (351) and the second moving device (352) may be hydraulic cylinders. However, the present invention is not limited thereto, and may also be a device whose shape can be changed by a gear, etc.

[0149] For a more detailed explanation, refer to FIGS. 13 to 15. For convenience of explanation, the following description will focus on the positional change of all, rather than some, of the multiple calendar rolls (300). It can be understood that the positional change of some of the multiple calendar rolls (300) is achieved by applying the same principle.

[0150] As illustrated in FIG. 13, the second moving device (352) may be reduced to reduce the gap between the plurality of calendar rolls (300). Accordingly, a gap may be created between the plurality of joining members (330).

[0151] As illustrated in Fig. 14, the first moving device (351) can press the outermost positioned joining member (330) so that the space between the joining members (330) becomes closer. In Fig. 14, it is illustrated that the first moving device (351) presses the leftmost joining member (330) to the right. Accordingly, the joining member (330) and the second moving device (352) can come into contact. At this time, when the force with which the second moving device (352) supports the joining member (330) corresponds to the force with which the first moving device (351) presses the outermost joining member (330), the movement of the joining member (330) can be completed. While the joining members (330) are moved in the order of Fig. 13 to Fig. 14, the space between the plurality of calendar rolls (300) can become narrower. Accordingly, the thickness of the mixture (110) can be reduced.

[0152] When the joining member (330) is moved in the order of FIG. 14 to FIG. 15, the space between the plurality of calendar rolls (300) can be widened. Accordingly, the thickness of the mixture (110) can be thickened.

[0153] More specifically, as illustrated in FIG. 15, the second moving device (352) may be deformed in a direction in which its thickness increases. The second moving device (352) may press an adjacent joining member (330) with a force stronger than the force with which the first moving device (351) presses the outermost joining member (330). When the second moving device (352) is extended, the joining members (330) may be moved in a direction in which the distance between the adjacent plurality of joining members (330) increases. When the distance between the plurality of joining members (330) increases, the distance between the plurality of calendar rolls (300) may increase. Accordingly, the thickness of the mixture (110) may increase.

[0154] According to the above process, when the moving device (351, 352) operates to change the space between some of the entire calendar rolls (300), only the thickness of the mixture (110) passing between some of the calendar rolls (300) can be changed. Furthermore, when only the position of one end of the calendar roll (300) is changed, only the thickness of the mixture (110) at that end can be changed. Accordingly, when there is a difference in the thickness of the edges of the mixture (110), the edges of each mixture (110) can be adjusted by adjusting both ends of the calendar roll (300).

[0155] To illustrate this adjustment, an example may be given:

[0156] Based on what is illustrated in FIG. 15, the plurality of calendar rolls (300) are defined as the first calendar roll (300a), the second calendar roll (300b), the third calendar roll (300), and the fourth calendar roll (300) from the left, and the following situation can be assumed. Furthermore, as illustrated in FIG. 9, the thickness of the mixture (110) measured by the first sensor device (401) is defined as the "thickness at A," and the thickness of the mixture (110) measured by the second sensor device (402) is defined as the "thickness at B." The "target thickness" below is the desired thickness. The "action at A" and the "action at B" at this time are each described in Table 1 below.

[0157] Thickness at A (mm) Thickness at B (mm) Target Thickness (mm) Action at A Action at B 1st Calendar Roll (300a) 205 203 200 Reduce the gap by 5 mm Reduce the gap by 3 mm 2nd Calendar Roll (300b) 152 140 150 Reduce the gap by 2 mm Widen the gap by 10 mm 3rd Calendar Roll (300) 95 99 100 Widen the gap by 5 mm Maintain 4th Calendar Roll (300) 55 47 50 Reduce the gap by 5 mm Widen the gap by 3 mm

[0158] The electrode (100) produced in this way may include a mixture (110) in which the widthwise thickness of the mixture (110) is uniform in one part and increases in another part in the widthwise direction. Since a process is performed to find that the border thickness is not uniform and to adjust the border thickness to be uniform, some of a specific electrode (100) may include a part with a uniform border and a part with an uneven border. In this case, the part in which the border is uneven is because the alignment of the calendar roll (300) is obliquely misaligned, so that the thickness of the mixture (110) can be arranged to change linearly. Hereinafter, embodiments different from the first embodiment will be described. Common contents with the first embodiment will be omitted as much as possible, and other embodiments will be described focusing on differences. In other words, it is obvious that contents not described in other embodiments can be supplemented through the contents of the first embodiment if necessary.

[0159] Second Example

[0160] FIG. 16 is a plan view illustrating a sensor device (400-1) according to a second embodiment of the present invention.

[0161] Referring to FIG. 16, a sensor device (400-1) according to a second embodiment of the present invention is described.

[0162] The second embodiment differs from the first embodiment in that the sensor device (400-1) is a sonar device using sound waves rather than a laser profile measuring device.

[0163] Third Example

[0164] Fig. 17 is a plan view illustrating a sensor device (400) according to a third embodiment of the present invention.

[0165] Referring to FIG. 17, a sensor device (400-2) according to a third embodiment of the present invention is described.

[0166] The third embodiment differs from the first embodiment in that the sensor device (400-2) is a device that measures thickness by a physical method rather than a laser profile measuring device.

[0167] The sensor device (400-2) may include a protruding portion whose length varies. As the protruding portion comes into contact with the surface of the mixture (110) or the calendar roll (300), the thickness of the mixture (110) can be measured. This contact-type measurement may be more accurate than a non-contact-type measurement.

[0168] Example 4

[0169] Figure 18 is a flowchart of a calendaring step according to the fourth embodiment of the present invention.

[0170] Referring to FIG. 18, the calendaring step according to the fourth embodiment of the present invention will be described.

[0171] The fourth embodiment differs from the first embodiment in that, rather than adjusting the gap between the plurality of calendar rolls (300) to ensure uniformity in the thickness of the mixture (110), the gap between the plurality of calendar rolls (300) is adjusted to make the thickness of the mixture (110) thinner or thicker.

[0172] The method for manufacturing an electrode (100) can determine, after the judgment step, whether the thickness of the mixture (110) formed by an adjacent pair of the plurality of calendar rolls (300) exceeds a predetermined range (S500-3).

[0173] In other words, when the thickness of the mixture (110) formed by an adjacent pair of a plurality of calendar rolls (300) exceeds a predetermined range, the control unit (900) can control the movement of the calendar rolls (300) to reduce the gap between the adjacent pair of calendar rolls (300) (S600-3).

[0174] The control unit (900) can control the movement of the calendar rolls (300) to widen the gap between the adjacent pair of calendar rolls (300) when the thickness of the mixture (110) formed by an adjacent pair of calendar rolls (300) is less than a predetermined range.

[0175] The control unit (900) can keep the spacing between adjacent calendar rolls (300) as is when the thickness of the mixture (110) formed by an adjacent pair of a plurality of calendar rolls (300) is predetermined.

[0176] Example 5

[0177] Figure 19 is a flowchart of a calendaring step according to the fifth embodiment of the present invention.

[0178] Referring to FIG. 19, the calendaring step according to the fifth embodiment of the present invention will be described.

[0179] The fifth embodiment differs from the first embodiment in that, in calendaring, the reliability of the determined thickness of the mixture (110) can be improved by measuring the surface uniformity of the calendar roll (300) before measuring the thickness of the mixture (110).

[0180] In other words, the control unit (900) may be configured to measure the surface uniformity of the calender roll (300) when the mixture (110) is not overlapped on the calender roll (300) (S110-4). More specifically, the surface uniformity of the roll body (310) may be measured. When the surface of the calender roll (300) is uniform (S120-4), the process may proceed to the pressing step (S200). However, when the surface of the calender roll (300) is not uniform (S120-4), the calender roll (300) may be controlled so that the surface of the calender roll (300) is uniform (S130-4), and the process may proceed to the pressing step (S200).

[0181] Figure 20 is a flowchart of a calendaring step according to the sixth embodiment of the present invention.

[0182] Referring to FIG. 20, the calendaring step according to the sixth embodiment of the present invention will be described.

[0183] The sixth embodiment differs from the first embodiment in that damage at the edge of the mixture (110) can be further determined by the present invention.

[0184] It can be determined whether there is a point with a thickness of 0 at each of a pair of edges of the determined mixture (110) (S410-5). If it is determined that there is a point with a thickness of 0, it can be determined that the edge of the mixture (110) is damaged (S420-5). In other words, the control unit (900) can determine that the edge of the mixture (110) is damaged based on the fact that the thickness of each of a pair of edges of the determined mixture (110) is 0.

[0185] If there is no point where the thickness is 0 (S410-5), the subsequent steps can be performed. For example, it can be determined whether the difference between the thicknesses of each pair of edges of the mixture (110) determined in the determination step is within a predetermined range (S500).

[0186] Unless explicitly stated otherwise, the embodiments described above may be combined with other embodiments. Alternatively, combinations between embodiments may be considered possible, unless one embodiment is explicitly restricted from being combined with another embodiment. Combinations of one embodiment with another embodiment are deemed to be disclosed in this document.

[0187] Although the present invention has been described above with reference to limited embodiments and drawings, the present invention is not limited thereto, and various embodiments are possible within the scope equivalent to the technical idea of ​​the present invention and the patent claims to be described below by a person having ordinary skill in the art to which the present invention pertains.

[0188] [Explanation of symbols]

[0189] 1: Calendaring System

[0190] B: Secondary battery

[0191] EA: Electrode Assembly

[0192] ES: Electrode laminate

[0193] 100: Electrode

[0194] 110: Mixture

[0195] 110a: Positive mixture

[0196] 110b: Cathode mixture

[0197] 111: Active material

[0198] 112: Binder

[0199] 112a: Fibrillar binder

[0200] 113: Challenge

[0201] 120: Whole house

[0202] 121: Electrode tab

[0203] 130: Electrode lead

[0204] 131: Insulation

[0205] 140: Membrane

[0206] 200: Battery case

[0207] 210: Reception area

[0208] 210S: Electrode receiving space

[0209] 220: Side section

[0210] 221: Lead sealing section

[0211] 222: Digas Department

[0212] 223: Folding section

[0213] CA: Calendar Device

[0214] 300: Calendar Roll

[0215] 300a: 1st calendar roll

[0216] 300b: Second Calendar Roll

[0217] 301A: Overlapping Area

[0218] 302A: Non-overlapping area

[0219] 310: Roll body

[0220] 320: Roll shaft

[0221] 330: Joining member

[0222] 340: Joint member guide

[0223] 351: First mobile device

[0224] 352: Second mobile device

[0225] 400: Sensor device

[0226] 400a: First pair of sensor devices

[0227] 400b: Second pair of sensor devices

[0228] 401: First sensor device

[0229] 402: Second sensor device

[0230] 500: Drive Unit

[0231] 900: Control Unit

[0232] 910: Processor

[0233] 920: Memory

Claims

1. A calendar device configured to press a mixture containing an active material and a binder, the calendar device including a calendar roll having an overlapping region positioned to overlap the mixture and a non-overlapping region positioned to limit overlap with the mixture; a pair of sensor devices configured to sense the non-overlapping region and a mixture having a pair of edges adjacent to the non-overlapping region; and A calendaring system comprising a control unit configured to determine a thickness at each of a pair of edges of the mixture based on information of the mixture and the non-overlapping area sensed by the pair of sensor devices.

2. In paragraph 1, The above sensor device is a calendaring system including a laser profile measuring device.

3. In paragraph 1, A calendaring system wherein the thickness at a pair of edges of the mixture is defined as the distance from the sensor device to the non-overlapping area minus the distance to the edge of the mixture.

4. In paragraph 1, A calendaring system wherein the control unit is configured to determine whether the mixture has a constant thickness between the pair of edges based on thickness information at each of the pair of edges of the determined mixture.

5. In paragraph 1, A calendaring system wherein the control unit is configured to determine that the calendaring is normal when the difference between the thicknesses of each pair of edges of the determined mixture is within a predetermined range.

6. In paragraph 1, A calendaring system in which the control unit is configured to control the calendar roll so as to reduce the difference in thickness when the difference between the thicknesses of each pair of edges of the determined mixture is greater than a predetermined range.

7. In paragraph 1, Further comprising a moving device configured to move one end of the longitudinal direction of the calendar roll or the other end located on the opposite side of the one end, A calendaring system in which the control unit is configured to control a moving device to move at least one of the one end or the other end of the calendar roll when the difference between the thicknesses of each of a pair of edges of the determined mixture is greater than a predetermined range.

8. In paragraph 1, A calendaring system wherein the pair of sensor devices are positioned adjacent to the boundary of the non-overlapping area and the overlapping area.

9. In paragraph 1, The above calendar rolls are provided in multiples so that the mixture is moved and compressed between them, A calendaring system in which the above pair of sensor devices are provided in plurality to correspond to at least one of the plurality of calendar rolls.

10. In paragraph 9, A virtual plane is defined that includes the rotational axis of each of the plurality of said calendar rolls, The plurality of said calendar rolls include a first calendar roll and a second calendar roll adjacent to the first calendar roll, The overlapping area of ​​the second calendar roll is located on the opposite side of the overlapping area of ​​the first calendar roll with respect to the virtual plane, The plurality of pairs of sensor devices include a first pair of sensor devices for sensing the first calendar roll and a second pair of sensor devices for sensing the second calendar roll, A calendaring system wherein the second pair of sensor devices are positioned on opposite sides of the virtual plane from the first pair of sensor devices.

11. In paragraph 9, A calendaring system in which the control unit obtains information about the thickness of each of the mixtures passing through the plurality of calendar rolls based on information obtained from each of the plurality of pairs of sensor devices.

12. In paragraph 11, A calendaring system in which the control unit controls movement of the calendar rolls to reduce the gap between adjacent pairs of the calendar rolls when the thickness of the mixture formed by adjacent pairs of the plurality of calendar rolls exceeds a predetermined range.

13. In paragraph 1, A calendaring system in which the control unit controls movement of the calendar rolls to widen the gap between adjacent pairs of the calendar rolls when the thickness of the mixture formed by adjacent pairs of the plurality of calendar rolls is below a predetermined range.

14. In paragraph 1, A calendaring system in which the control unit determines that the edges of the mixture are damaged based on the thickness of each of the pair of edges of the mixture being determined to be 0.

15. In paragraph 1, A calendaring system wherein the control unit is configured to measure the surface uniformity of the calendar roll when the mixture is not overlapped on the calendar roll.

16. Preparatory step of preparing a mixture containing an active material and a binder; A pressing step in which the mixture is pressed by the calendar roll, wherein the calendar roll has an overlapping area positioned to overlap the mixture and a non-overlapping area positioned to limit overlap with the mixture; A sensing step in which a mixture having a pair of edges adjacent to the non-overlapping area and the non-overlapping area are sensed by a pair of sensor devices; and An electrode manufacturing method comprising a judgment step of judging the thickness of each of a pair of edges of the mixture based on information of the mixture and the non-overlapping area sensed by the pair of sensor devices.

17. In paragraph 16, The above sensor device is an electrode manufacturing method including a laser profile measuring device.

18. In paragraph 16, An electrode manufacturing method in which the above judgment step is performed to determine the thickness at a pair of edges of the mixture by subtracting the distance from the non-overlapping area in the sensor device to the edge of the mixture.

19. In paragraph 16, An electrode manufacturing method further comprising a control step of controlling the calendar roll so as to reduce the difference in thickness when the difference between the thicknesses of each pair of edges of the mixture determined in the judgment step is greater than a predetermined range.

20. A mixture containing an active material and a binder; and Including a collector to which the above mixture is combined, An electrode in which the widthwise thickness of the above mixture is uniform in one part and increases in the widthwise direction in one part.

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