Die assembly and method of manufacturing die assembly and punch holder and die holder therefor

Abstract

The present disclosure relates to a mold assembly for notching or cutting an electrode plate of a secondary battery and a method of manufacturing the same. The present disclosure provides a method of manufacturing a punch holder and a die holder of a die assembly for notching an electrode plate of a secondary battery, and a notching die assembly manufactured by the method, the method comprising: fixedly overlapping the punch holder and the die holder; simultaneously polishing side surfaces of the punch holder and the mold holder that overlap each other; setting a center point of each of the punch holder and the mold holder that overlap each other; and creating a reference hole through each of the punch holder and the mold holder overlapping each other at a position spaced apart from the center point.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to a die assembly for cutting or slitting an electrode plate of a secondary battery and a method of manufacturing the die assembly. BACKGROUND

[0002] While primary batteries are not designed to be (re)charged, secondary (also referred to as rechargeable) batteries are designed to be discharged and recharged. In secondary batteries, low-capacity secondary batteries are widely used for portable small electronic devices such as smartphones, feature phones, notebook computers, digital cameras, and camcorders, and high-capacity secondary batteries are widely used as power sources for driving electric motors in hybrid and electric vehicles and for storing electric power (e.g., home and / or utility-scale power storage). A secondary battery generally includes an electrode assembly having a positive electrode and a negative electrode, a case accommodating the two electrodes, and an electrode terminal connected to the electrode assembly.

[0003] A positive electrode plate or a negative electrode plate can be manufactured through a coating, a roll-pressing, a slitting, and a cutting process. In the cutting process, the electrode plate is manufactured by cutting unnecessary portions of a substrate using a shearing die and forming an electrode tab. The cutting die assembly includes a pair of punches and a die punched according to a required shape and punch plates and die plates to which the pair of punches and the die are respectively assembled. The cutting die assembly is installed in a punch press apparatus for operating the cutting die assembly.

[0004] Since all the components of the die assembly apparatus are individually machined in order to assemble the cutting die assembly, the assembly accuracy can be degraded due to dimensional deviations between the components when the cutting die assembly is assembled. In addition, since there is no reference point for measuring the positions of the punches and the die even after the die assembly is assembled, the distance between the punches and the die can be measured only roughly.

[0005] The information disclosed in this Background section is for the purpose of enhancing the understanding of the background of the present disclosure. It can include information that does not constitute the related (or prior) art. SUMMARY

[0006] The present disclosure aims to provide a method of ensuring the assembly accuracy of punch plates and die plates, particularly when manufacturing a cutting die assembly requiring precision, and enabling accurate measurement after assembly.

[0007] Embodiments of the present disclosure provide a die assembly for cutting an electrode plate of a secondary battery, the die assembly including a punch holder in which a recess is machined, a punch for cutting an electrode plate of a secondary battery, a die holder in which a recess is machined, and a die for cutting an electrode plate of a secondary battery mounted on the recess, and side surfaces of the punch holder and the die holder are aligned with each other, the punch holder and the die holder have a common center point at the same position, and the punch holder and the die holder have a common reference hole machined at a position spaced apart from the center point by a distance.

[0008] Embodiments of the present disclosure provide a die assembly, the die assembly including a punch holder including a first recess configured to accommodate a punch for cutting an electrode plate of a secondary battery, and a die holder including a second recess configured to accommodate a die for cutting the electrode plate placed on the second recess, wherein side surfaces of each of the punch holder and the die holder are aligned with each other, wherein each of the punch holder and the die holder has a center point at the same position, and wherein each of the punch holder and the die holder has a reference hole at the same position spaced apart from the center point.

[0009] In an embodiment, the punch holder and the die holder are fixedly overlapped with each other, and wherein the side surfaces of each of the punch holder and the die holder are flush when polished at the same time.

[0010] In an embodiment, the position of the center point of each of the punch holder and the die holder is based on the side surfaces of each of the punch holder and the die holder.

[0011] In an embodiment, the first recess is machined based on the reference hole of the punch holder, and wherein the second recess is machined based on the reference hole of the die holder.

[0012] In an embodiment, the die assembly further includes a pin inserted into the reference hole of the punch holder and the reference hole of the die holder.

[0013] Embodiments of the present disclosure provide a method of manufacturing a punch holder and a die holder of a die assembly for cutting an electrode plate of a secondary battery, the method including: fixedly overlapping a punch holder and a die holder; polishing side surfaces of the punch holder and the die holder overlapped with each other at the same time; setting a center point of each of the punch holder and the die holder overlapped with each other; and machining a reference hole through each of the punch holder and the die holder overlapped with each other at a position spaced apart from the center point by a distance.

[0014] Embodiments of the disclosure provide a method of manufacturing a punch holder and a die holder of a die assembly for cutting an electrode plate of a secondary battery, the method including: fixedly overlapping the punch holder and the die holder; simultaneously polishing side surfaces of each of the punch holder and the die holder; setting a center point of each of the punch holder and the die holder; and generating a reference hole through each of the punch holder and the die holder at a position spaced apart from the center point.

[0015] In an embodiment, the method further includes, before the fixedly overlapping, polishing respective surfaces of the punch holder and the die holder that are to be contacted.

[0016] In an embodiment, the setting includes setting the center point based on the side surfaces of each of the punch holder and the die holder that are simultaneously polished.

[0017] In an embodiment, the method further includes generating a recess in each of the punch holder and the die holder based on the reference hole.

[0018] In an embodiment, the method further includes, before the fixedly overlapping, rough machining a recess in each of the punch holder and the die holder.

[0019] In an embodiment, the fixedly overlapping includes fixing the punch holder and the die holder using clamping, bolting, or welding.

[0020] Embodiments of the disclosure provide a method of manufacturing a die assembly for cutting an electrode plate of a secondary battery, the method including: fixedly overlapping a punch holder and a die holder; simultaneously polishing side surfaces of the punch holder and the die holder that overlap each other; setting a center point of each of the punch holder and the die holder that overlap each other; machining a reference hole through each of the punch holder and the die holder that overlap each other at a position spaced apart from the center point by a distance; and assembling the punch holder and the die holder in which the reference hole is machined.

[0021] Embodiments of the disclosure provide a method of manufacturing a die assembly for cutting an electrode plate of a secondary battery, the method including: fixedly overlapping a punch holder and a die holder; simultaneously polishing side surfaces of each of the punch holder and the die holder; setting a center point of each of the punch holder and the die holder; generating a reference hole through the punch holder and the die holder at a position spaced apart from the center point; and assembling the punch holder and the die holder via the reference hole.

[0022] In an embodiment, the method further comprises polishing respective surfaces of the punch support and the die support that are to contact, prior to the fixedly overlapping.

[0023] In an embodiment, the setting comprises setting the center point based on the side surfaces of each of the punch support and the die support that are polished simultaneously.

[0024] In an embodiment, the method further comprises creating a recess in each of the punch support and the die support based on the reference hole.

[0025] In an embodiment, the method further comprises roughening a recess in each of the punch support and the die support, prior to the fixedly overlapping.

[0026] In an embodiment, the fixedly overlapping comprises fixing the punch support and the die support using clamping, bolting, or welding.

[0027] In an embodiment, the assembling comprises inserting a pin into the reference hole of the punch support and the reference hole of the die support. BRIEF DESCRIPTION OF DRAWINGS

[0028] The accompanying drawings, which are incorporated in and form a part of the specification, illustrate embodiments of the present disclosure and, together with the description, further describe the aspects and features of the present disclosure. The present disclosure is not, therefore, to be construed as limited to the

[0029] Figure 1 is a schematic view illustrating an electrode assembly of a secondary battery according to an embodiment of the present disclosure;

[0030] Figure 2 is a schematic view illustrating a pouch-type secondary battery according to an embodiment of the present disclosure;

[0031] Figure 3 is a cross-sectional view of a cylindrical secondary battery according to an embodiment of the present disclosure;

[0032] Figure 4 illustrates an internal configuration of a prismatic secondary battery according to an embodiment of the present disclosure;

[0033] Figure 5 illustrates an electrode plate before and after the electrode plate is slitted by a slitting die assembly according to an embodiment of the present disclosure;

[0034] Figure 6 is a schematic view of a slitting die assembly according to an embodiment of the present disclosure;

[0035] Figure 7 is a schematic view of a slitting die assembly according to an embodiment of the present disclosure; Figure 6a perspective view of a press apparatus in which a punch and a die are installed;

[0036] Figure 8 is a perspective view illustrating a punch holder and a die holder according to an embodiment of the disclosure; Figure 7 is a vertical sectional view of a press apparatus shown;

[0037] Figure 9 illustrates a punch holder and a die holder according to an embodiment of the disclosure;

[0038] Figure 10 is a flowchart illustrating a method of manufacturing a punch holder and a die holder according to an embodiment of the disclosure;

[0039] Figures 11A-11E illustrates a punch holder and a die holder according to a process of Figure 10 according to an embodiment of the disclosure; and

[0040] Figure 12 is a flowchart illustrating a method of manufacturing a punch holder and a die holder according to an embodiment of the disclosure;

[0041] Figures 13A-13E illustrates a punch holder and a die holder according to a process of Figure 12 according to an embodiment of the disclosure; and

[0042] Figure 14 illustrates a die assembly for cutting an electrode plate of a secondary battery including a punch holder and a die holder according to an embodiment of the disclosure. DETAILED DESCRIPTION

[0043] Hereinafter, embodiments of the disclosure will be described in detail with reference to the accompanying drawings. The terms or words used in the present specification and claims should not be interpreted as being limited to commonly or dictionary definitions thereof, and should be interpreted as having a concept matching the technical idea of the present disclosure based on the principle that an inventor can appropriately define the concept of the terms to best describe his / her own invention.

[0044] The embodiments described in the present specification and the configurations shown in the drawings are only some embodiments of the disclosure, and do not represent all aspects, features, and embodiments of the disclosure. Accordingly, it should be understood that, at the time of filing the present application, there can be various equivalents and modifications that can substitute or modify one or more embodiments described herein or features thereof.

[0045] It will be understood that if an element or layer is referred to as being “on” another element or layer, “connected to” or “coupled to” another element or layer, it can be directly on, connected or coupled to the other element or layer or one or more intervening elements or layers can also be present. In contrast, if an element or layer is referred to as being “directly on,” “directly connected to,” or “directly coupled to” another element or layer, there are no intervening elements or layers present. For example, if a first element is described as being “coupled” or “connected” to a second element, the first element can be directly coupled or connected to the second element or the first element can be indirectly coupled or connected to the second element via one or more intervening elements.

[0046] Embodiments described herein can be explained with reference to cross-sectional and / or plan views that are examples of the present disclosure. In the drawings, the size of various elements, layers, etc. can be exaggerated for clarity. Thus, the examples presented herein are by way of example only and should not be construed as limiting the scope of the present disclosure. While terms such as “first,” “second,” and “third” can be used in describing various elements, components, regions, layers and / or sections, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. Embodiments described and illustrated herein include complementary embodiments. Like reference numerals designate like elements.

[0047] As used herein, the term “and / or” includes any and all combinations of one or more of the associated listed items. Further, use of “may” in describing embodiments of the present disclosure relates to “one or more embodiments of the present disclosure.” Expressions such as “at least one of,” when preceding a list of elements, modify the entire list of elements and do not modify the individual elements of the list. When a phrase such as “at least one of,” “at least one,” or “one or more of,” is used in conjunction with a list of two or more elements or entities, for example, elements A, B, and C, the phrase is intended to mean A alone, B alone, C alone, A and B together, A and C together, B and C together, or A, B, and C together. As used herein, the term “use” can be taken to be synonymous with the term “utilize.” As used herein, the terms “substantially,” “about,” and similar terms are used as approximating terms and not as terms of degree, and are intended to account for the inherent variations in measurements or calculations that would be recognized by those of ordinary skill in the art.

[0048] It will be understood that, although the terms“first,”“second,”“third,” etc. can be used herein to describe various elements, components, regions, layers and / or sections, these elements, components, regions, layers and / or sections should not be limited by these terms. These terms are used to distinguish one element, component, region, layer or section from another element, component, region, layer or section. Thus,“a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the example embodiments.

[0049] Spatially relative terms such as“beneath,”“below,”“lower,”“above,”“upper” and the like can be used herein for ease of description to describe one element or feature’s relationship to another element(s) or feature(s) as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientations depicted in the figures. For example, if a device in the figures is turned over, elements described as“below” or“beneath” other elements or features would then be oriented“above” or“over” the other elements or features. Thus, the term“below” can encompass both an orientation of above and below. The device can be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

[0050] The terminology used herein is for the purpose of describing embodiments of the present disclosure and is not intended to be limiting of the present disclosure. As used herein, the singular forms“a,”“an” and“the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms“comprises,”“comprising,”“includes” and / or“including,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0051] Further, any numerical ranges recited herein are intended to include all sub-ranges of the same numbers precision subsumed within the recited range. For example, a range of 1.0 to 10.0 should be read to include any number between and including 1.0 and 10.0, such as, e.g., 2.4 to 7.6. Any maximum numerical limitation recited herein is intended to include all lower numerical limitations subsumed therein and any minimum numerical limitation recited in this specification is intended to include all higher numerical limitations subsumed therein. Accordingly, it is the intention of the applicants to retain, by way of example, the right to "amend the specification to expressly recite any sub-range included within the ranges recited herein." All such ranges are intended to be inherently described in this specification such that amending the specification to expressly recite any sub-range would comply with the requirements of 35 U.S.C. § 112, first paragraph, and 35 U.S.C. § 132(a).

[0052] Referring to two compared elements, features, etc., as "the same" can mean that they are "substantially the same." Thus, the phrase "substantially the same" can include cases where deviations are considered low in the art, for example, 5% or less. Also, if a certain parameter is referred to as uniform in a given region, this can mean that it is uniform in terms of average value.

[0053] Throughout the specification, unless otherwise indicated, each element can be single or multiple.

[0054] Arranging an arbitrary element "above (or below)" or "on (under)" another element can mean that the arbitrary element can be in contact with the upper surface (or lower surface) of the element, and another element can also be interposed between the element and the arbitrary element located on (under) the element.

[0055] In addition, it will be understood that if a component is referred to as being "linked," "coupled," or "connected" to another component, that the element can be "coupled," "linked," or "connected" directly to the other component, or another component can be "interposed" between the elements.

[0056] Throughout the specification, unless otherwise stated, if "A and / or B" is stated, it means A, B, or A and B. That is, "and / or" includes any or all combinations of the listed items. Unless otherwise stated, when "C~D" is stated, it means C or more and D or less.

[0057] The terms used herein are used for the purpose of describing embodiments of the present disclosure and are not intended to limit the present disclosure.

[0058] Figure 1 is a schematic view showing an electrode assembly of a secondary battery according to an embodiment of the present disclosure.

[0059] The electrode assembly 10 can be formed by winding or stacking a stack of the first electrode plate 11, the separator 12, and the second electrode plate 13 each formed as a thin sheet or film. When the electrode assembly 10 is a wound stack, a winding axis can be parallel to a longitudinal direction of the case. In some embodiments, the electrode assembly 10 can be a stacked type. The shape of the electrode assembly 10 is not limited in the present disclosure. The electrode assembly 10 can be a Z-stack electrode assembly in which positive and negative electrode plates are inserted to both sides (e.g., opposite sides) of a separator, and then the Z-stack electrode assembly is bent (or folded) into a Z-stack. A plurality of electrode assemblies can be stacked (e.g., arranged) such that the longitudinal sides of the electrode assemblies are adjacent to each other and accommodated in the case. The number of electrode assemblies in the case is not limited in the present disclosure. The first electrode plate 11 of the electrode assembly can be configured as a negative electrode, and the second electrode plate 13 can be configured as a positive electrode, or vice versa.

[0060] The first electrode plate 11 can be formed by applying (e.g., coating or depositing) a first electrode active material such as graphite or carbon onto a first electrode substrate formed of a metal foil including copper, a copper alloy, nickel, or a nickel alloy. The first electrode plate 11 can include a first electrode tab 14 (e.g., a first uncoated portion) that is a region to which the first electrode active material is not applied. The first electrode tab 14 can be connected to an external first terminal. In some embodiments, when the first electrode plate 11 is manufactured, the first electrode tab 14 can be formed by being pre-cut to protrude to or from one side of the electrode assembly 10. In some embodiments, the first electrode tab 14 can protrude further to or from one side of the electrode assembly 10 than the separator 12 or protrude beyond the separator 12 without being separately cut.

[0061] The second electrode plate 13 can be formed by applying (e.g., coating or depositing) a second electrode active material such as a transition metal oxide onto a second electrode substrate formed of a metal foil including aluminum or an aluminum alloy. The second electrode plate 13 can include a second electrode tab 15 (e.g., a second uncoated portion) that is a region to which the second electrode active material is not applied. The second electrode tab 15 can be connected to an external second terminal. In some embodiments, when the second electrode plate 13 is manufactured, the second electrode tab 15 can be formed by being pre-cut to protrude to or from the other side (e.g., the opposite side) of the electrode assembly 10. In some embodiments, the second electrode tab 15 can protrude further to or from the other side of the electrode assembly than the separator 12 or protrude beyond the separator 12 without being separately cut.

[0062] The separator 12 prevents short-circuiting between the first electrode plate 11 and the second electrode plate 13 while allowing lithium ions to migrate therebetween. The separator 12 can include a polyethylene film, a polypropylene film, a polyethylene-polypropylene film, or the like.

[0063] In some embodiments, the electrode assembly 10 can be housed in a case together with an electrolyte. In a pouch-type secondary battery, the electrode assembly 10 can be housed in a pouch made of a flexible material (see, e.g., Figure 2 ). In a cylindrical or prismatic secondary battery, the electrode assembly 10 can be housed in a cylindrical or prismatic metal case (see, e.g., Figure 3 and Figure 4 ).

[0064] The positive electrode active material can include a compound capable of reversibly intercalating / deintercalating lithium (e.g., lithiated intercalation compounds). In some embodiments, the positive electrode active material can include at least one of a composite oxide of lithium and a metal including cobalt, manganese, nickel, or a combination thereof.

[0065] The composite oxide can include a lithium transition metal composite oxide, such as a lithium nickel-based oxide, a lithium cobalt-based oxide, a lithium manganese-based oxide, a lithium iron phosphate-based compound, a cobalt-free nickel-manganese-based oxide, or a combination thereof.

[0066] In some embodiments, the composite oxide can include a compound represented by any one of the following molecular formulas: Li a A 1-b X b O 2-c D c (0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.05); Li a Mn 2-b X b O 4-c D c (0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.05); Li a Ni 1-b-c Co b X c O 2-α D α (0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.5, 0<α<2); Li a Ni 1-b-c Mn b X c O 2-α D α (0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.5, 0<α<2); Li a Ni b Co cL 1 d G e O2(0.90≤a≤1.8, 0≤b≤0.9, 0≤c≤0.5, 0≤d≤0.5, 0≤e≤0.1); Li a NiG b O2(0.90≤a≤1.8, 0.001≤b≤0.1); Li a CoG b O2(0.90≤a≤1.8, 0.001≤b≤0.1); Li a Mn 1-b G b O2(0.90≤a≤1.8, 0.001≤b≤0.1); Li a Mn2G b O4(0.90≤a≤1.8, 0.001≤b≤0.1); Li a Mn 1- g G g PO4(0.90≤a≤1.8, 0≤g≤0.5); Li (3-f) Fe2(PO4)3(0≤f≤2); and Li a FePO4(0.90≤a≤1.8), wherein A is Ni, Co, Mn, or a combination thereof; X is Al, Ni, Co, Mn, Cr, Fe, Mg, Sr, V, a rare earth element, or a combination thereof; D is O, F, S, P, or a combination thereof; G is Al, Cr, Mn, Fe, Mg, La, Ce, Sr, V, or a combination thereof; and L 1 is Mn, Al, or a combination thereof.

[0067] The positive electrode for a lithium secondary battery can include a substrate and a positive electrode active material layer on the substrate. The positive electrode active material layer can include a positive electrode active material, and can further include a binder and / or a conductive material.

[0068] The positive electrode active material can include about 90 wt% to about 99 wt% based on 100 wt% of the positive electrode active material layer, and the binder can include about 0.5 wt% to about 5 wt% and the conductive material can include about 0.5 wt% to about 5 wt% based on 100 wt% of the positive electrode active material layer.

[0069] The substrate can include aluminum (Al), but is not limited thereto.

[0070] The negative electrode active material can include a material capable of reversibly intercalating / deintercalating lithium ions, lithium metal, an alloy of lithium metal, a material capable of doping and undoping lithium, or a transition metal oxide.

[0071] The material capable of reversibly intercalating / deintercalating lithium ions can include a carbon-based negative electrode active material, which includes crystalline carbon, amorphous carbon, or a combination thereof. In an embodiment, the crystalline carbon can include graphite, such as natural graphite or artificial graphite, and the amorphous carbon can include soft carbon, hard carbon, pitch carbide (e.g., mesophase pitch carbide), sintered coke, or the like.

[0072] The Si-based negative electrode active material or the Sn-based negative electrode active material can be used as a material capable of doping and dedoping lithium. The Si-based negative electrode active material can include silicon, a silicon-carbon composite, SiO x ((0 < x < 2), a Si-based alloy, or a combination thereof.

[0073] The silicon-carbon composite can include a composite of silicon and / or amorphous carbon. According to an embodiment, the silicon-carbon composite can exist in the form of silicon particles and amorphous carbon coated on the surface of the silicon particles.

[0074] The silicon-carbon composite can further include crystalline carbon. In an embodiment, the silicon-carbon composite can include a core including crystalline carbon and silicon particles, and an amorphous carbon coating layer on the surface of the core.

[0075] The negative electrode for a lithium secondary battery can include a substrate and a negative electrode active material layer on the substrate. The negative electrode active material layer can include a negative electrode active material, and can further include a binder and / or a conductive material.

[0076] The negative electrode active material layer can include about 90 wt% to about 99.5 wt% of a negative electrode active material, about 0.5 wt% to about 5 wt% of a binder, and about 0 wt% to about 5 wt% of a conductive material, based on 100 wt% of the negative electrode active material layer.

[0077] The binder can include a non-aqueous binder, an aqueous binder, a dry binder, or a combination thereof. When an aqueous binder is used as a negative electrode binder, a cellulose-based compound capable of enhancing viscosity can be further included.

[0078] The negative electrode substrate can include a copper foil, a nickel foil, a stainless steel foil, a titanium foil, a nickel foam, a copper foam, a polymer substrate coated with a conductive metal, or a combination thereof.

[0079] The electrolyte for a lithium secondary battery can include a non-aqueous organic solvent and / or a lithium salt.

[0080] The non-aqueous organic solvent is configured to serve as a medium through which ions participating in an electrochemical reaction of the battery can migrate.

[0081] The non-aqueous organic solvent can include a carbonate-based, an ester-based, an ether-based, a ketone-based, an alcohol-based solvent, an aprotic solvent, or a combination.

[0082] In one embodiment, when using carbonate solvents, a mixture of cyclic carbonates and chain carbonates can be used.

[0083] Depending on the type of lithium-ion secondary battery, a separator may be present between a first electrode plate (e.g., the negative electrode) and a second electrode plate (e.g., the positive electrode). The separator may include polyethylene, polypropylene, polyvinylidene fluoride, or a multilayer film comprising two or more layers thereof.

[0084] The diaphragm may include a porous substrate and a coating of organic material, inorganic material or a combination thereof on one or both surfaces of the porous substrate.

[0085] Organic materials may include polyvinylidene fluoride polymers or (meth)acrylic acid polymers.

[0086] Inorganic materials may include inorganic particles, including Al2O3, SiO2, TiO2, SnO2, CeO2, MgO, NiO, CaO, GaO, ZnO, ZrO2, Y2O3, SrTiO3, BaTiO3, Mg(OH)2, boehmite or combinations thereof, but are not limited thereto.

[0087] Organic and inorganic materials can be combined into a coating, or it can be a coating that includes (or contains) organic materials and a coating that includes (or contains) inorganic materials stacked on top of another coating.

[0088] Figure 2 This is a schematic diagram illustrating a pouch-type secondary battery according to an embodiment of the present disclosure.

[0089] The pouch-type secondary battery includes an electrode assembly 10 and a pouch 20 for housing the electrode assembly 10.

[0090] Electrode assembly 10 can be with Figure 1 The electrode assembly 10 shown is substantially the same. The first electrode tab 14 and the second electrode tab 15 of the electrode assembly 10 can be electrically connected by soldering to corresponding external first terminal lead 16 and second terminal lead 17. Each of the first terminal lead 16 and the second terminal lead 17 may be attached with a tab film 18 for insulation from the bag 20.

[0091] The bag 20 can be sealed by accommodating the electrode assembly 10 therein while bringing its sealing portions 21 at their edges into contact with each other. The seal can be achieved using a connecting film 18 positioned between the sealing portions 21. Each sealing portion 21 of the bag 20 may comprise a heat-fused material that typically has weak adhesion to metals. Therefore, the sealing portions 21 can be fused to the bag 20 by placing a thin connecting film 18 between the sealing portions 21.

[0092] Figure 3is a cross-sectional view of a cylindrical secondary battery according to an embodiment of the disclosure. The secondary battery can include an electrode assembly 10, a case accommodating the electrode assembly 10 and an electrolyte, a cap assembly 32 coupled to an opening of the case to seal the case, and an insulating plate 33 between the electrode assembly 10 and the cap assembly 32 within the case.

[0093] The case accommodates the electrode assembly 10 and the electrolyte, and forms an outer appearance of the battery together with the cap assembly 32. The case can have a substantially cylindrical body portion and a bottom portion. A crimped portion 34 recessed toward an inner side can be located in the body portion of the case, and a crimped portion 35 bent toward an inner side can be located at an opening side end portion of the body portion of the case.

[0094] The crimped portion 34 is configured to reduce or prevent movement of the electrode assembly 10 inside the case, and can facilitate seating of a gasket 36 and the cap assembly 32. The crimped portion 35 can firmly fix the cap assembly 32 by pressing an edge of the case against the gasket 36. The case can include nickel-plated iron.

[0095] The cap assembly 32 can be fixed to an inner side of the crimped portion 35 via the gasket 36 to seal the case. A first lead tab 37 led out from the electrode assembly 10 can be connected to the cap assembly 32, and a second lead tab 38 led out from the electrode assembly 10 can be electrically connected to a bottom portion of the case.

[0096] Figure 4 An internal configuration of a prismatic battery according to an embodiment of the disclosure and a structure of a cap assembly 60 are shown.

[0097] The type of electrode assembly 40 used in the prismatic battery can also be formed by winding a first electrode plate, a separator, and a second electrode plate as shown in Figure 1 When the electrode assembly 40 is a wound stack, a winding axis can be parallel to a longitudinal direction of the case 59. In an embodiment, the electrode assembly 40 can be a stacked type. The shape of the electrode assembly 40 is not limited in the disclosure.

[0098] In an embodiment, the electrode assembly 40 can be a Z-stack electrode assembly in which a positive electrode plate and a negative electrode plate are inserted to both sides of a separator, and then the Z-stack electrode assembly is bent into a Z-stack. In an embodiment, a plurality of electrode assemblies can be stacked such that longitudinal sides of the electrode assemblies are adjacent to each other and accommodated in the case 59. The number of electrode assemblies in the case 59 is not limited in the disclosure. The first electrode plate of the electrode assembly can be configured as a negative electrode, and the second electrode plate can be configured as a positive electrode, or vice versa.

[0099] In some embodiments, the electrode assembly 40 is accommodated in the case 59 together with an electrolyte.

[0100] The first electrode tabs 43 of the first electrode plate and the second electrode tabs 44 of the second electrode plate extend from both ends of the electrode assembly 40, respectively.

[0101] In the electrode assembly 40, the first current collector 41 and the second current collector 42 can be respectively welded and connected to the first electrode tabs 43 extending from the first electrode plate and the second electrode tabs 44 extending from the second electrode plate. In some embodiments in which the first electrode tabs 43 and the second electrode tabs 44 are located at the top of the electrode assembly 40, the first current collector and the second current collector can be located at the top of the electrode assembly 40.

[0102] The first current collector 41 and the second current collector 42 are connected to the first terminal 62 and the second terminal 63, respectively, via the connection members 67. In some embodiments, the connection members 67 can each have an outer circumferential surface with threads and can be fastened to the first terminal 62 and the second terminal 63 by tightening. However, the present disclosure is not limited thereto. In an embodiment, the connection members 67 can also be coupled to the first terminal 62 and the second terminal 63 by riveting or welding.

[0103] A substrate for manufacturing an electrode plate can include a metal foil including aluminum (Al) (in the case of a positive electrode) or a metal foil including copper (Cu) or nickel (Ni) (in the case of a negative electrode). In a coating process, the substrate is coated with a previously prepared slurry or powdered mixture (e.g., a mixture of electrode materials) to form a coating layer. Subsequently, in a roll-pressing, the coated substrate can be roll-pressed by a roller to manufacture a high-capacity, high-density secondary battery. The roll-pressed substrate is cut in a longitudinal direction in a slitting process to be separated into individual electrode plates, and is shaped into individual electrode plates in a cutting process.

[0104] Figure 5 is a general description of the cutting process and shows the shape of an electrode plate before and after cutting according to an embodiment of the present disclosure.

[0105] In the cutting process, the substrate 79 previously coated with the active material 72 can be cut in a transverse direction along a transverse cutting line 78 and in a longitudinal direction along a longitudinal cutting line 80 by a cutting unit. The cutting unit can be removed, and the uncoated portion 74 is trimmed along a shaping line 81. The cut electrode plate 82 has a region coated with a positive electrode material or a negative electrode material and a tab 86, which is an uncoated region, as shown on the right-hand side of Figure 5 is a general description of the cutting process and shows the shape of an electrode plate before and after cutting according to an embodiment of the present disclosure.

[0106] Figure 6 is a schematic view of a cutting die assembly according to an embodiment of the present disclosure.

[0107] A die assembly used for cutting notches in the electrode plates of a secondary battery can be called a cutting die assembly. When the electrode plate 106 is loaded onto the die 104, the punch 102 moves downward and punches the electrode plate 106 according to the design shape to manufacture a die with the following characteristics: Figure 5 The electrode plate has the shape shown. The punch 102 can be supported by the punch plate 108, and the mold 104 can be supported by the mold plate 110.

[0108] Punch 102 and die 104 may include a pair of punches and a die, thereby enabling simultaneous stamping and forming. Figure 5 The electrode plate shown has a terminal block 86 and its opposite side.

[0109] Figure 7 An embodiment of the present disclosure is shown for operation Figure 6 A perspective view of a stamping device with punch 102 and die 104. Figure 6 The institutions included Figure 7 In part I. Figure 8 According to embodiments of this disclosure Figure 7 The diagram shows a vertical cross-sectional view of the stamping equipment.

[0110] The cutting die assembly 100 may include an upper die assembly and a lower die assembly. The upper die assembly may include a punch holder 112 for fixing the punch plate 108 and an upper slider 114 for supporting the punch holder 112. The lower die assembly may include a die holder 116 for fixing the die plate 110 and a lower slider 118 for supporting the die holder 116. The upper die assembly may move vertically relative to the lower die assembly via a guide post 120. The guide post 120 may include a main post 120a and a sub-post 120b.

[0111] As used herein, punch 102 and punch plate 108 can exist as a single component and are therefore collectively referred to as punch 102. Similarly, mold 104 and mold plate 110 can also exist as a single component and are therefore collectively referred to as mold 104.

[0112] Figure 9 The punch holder 112 and the die holder 116 according to embodiments of the present disclosure are shown in more detail.

[0113] The punch holder 112 may include a terminal punch recess 126 and a bottom punch recess 128. The terminal punch recess 126 is an opening into which the punch can be inserted, and the bottom punch recess 128 is an opening into which the punch can be inserted. A hole 124 connecting to the mold holder 116 may also be formed in the punch holder 112. The sub-post 120b may be connected to the hole 124.

[0114] The die holder 116 can include a tab die recess 132 corresponding to the tab punch recess 126 and a bottom die recess 134 corresponding to the bottom punch recess 128. A hole 130 coupled to the punch holder 112 can be formed in the die holder 116. The sub-post 120b can be coupled to the hole 130.

[0115] Since the components of the cut die assembly can be individually machined, the assembly accuracy can be lowered due to dimensional deviation between the components when the cut die assembly is assembled. Since there is no reference point for measuring the positions of the punch and the die even after the die assembly is assembled, the distance between the punch and the die can only be roughly measured.

[0116] The accuracy of the cut die assembly can need to withstand a lateral load generated by a repulsive force of a machined target during cutting. For this reason, the accuracy of the recess to which the punch and the die are assembled is required to minimize the gap of the punch and the die.

[0117] The gap refers to the gap between the punch and the die in the cut die assembly. When the gap is large, burrs can be generated on a product (for example, an electrode plate) after cutting. The gap of a typical cut die assembly is in the range of about 0.01 mm ~ 0.02 mm, and the gap of an ultra-precision cut die assembly is in the range of about 0.001 mm ~ 0.002 mm. To satisfy the ultra-precision gap, the precision die assembly is machined and assembled, thereby increasing the number of processes and costs of the die assembly. When the die assembly is poor, the die assembly can be broken, and when accurate assembly cannot be performed, re-grinding, re-adjustment, etc. are required, which is a factor of cost increase.

[0118] Advantageously, the present disclosure provides a cut die assembly for an electrode plate of a secondary battery, which includes a punch holder 112 in which a punch recess is machined at an accurate position and a die holder 116 in which a die recess is machined at an accurate position, and for this reason, a method of accurately manufacturing a punch holder 112 in which a punch recess is machined / will be machined and a die holder 116 in which a die recess is machined / will be machined, and a method of assembling the punch holder 112 and the die holder 116 accurately manufactured by the cut die assembly.

[0119] Figure 10 is a flowchart illustrating a method of manufacturing a punch holder 112 and a die holder 116 according to an embodiment of the present disclosure. Figures 11A-11E illustrates a punch holder 112 and a die holder 116 according to a process of Figure 10 according to an embodiment of the present disclosure.

[0120] In operations S10 and S20, a punch holder material 112' for manufacturing a punch holder and a die holder material 116' for manufacturing a die holder are prepared. Figure 11A The punch holder material 112' and the die holder material 116' are shown. The punch holder material 112' overlaps the die holder material 116'.

[0121] In operation S30, before the punch holder material 112' overlaps the die holder material 116', the overlapping surfaces (i.e., the respective surfaces to be contacted) of each material can be polished. Operation S30 can be selectively performed according to the state of the overlapping surfaces of the punch holder material 112' and the die holder material 116' or according to the precision design specification of the punch holder 112 and the die holder 116 to be finally manufactured.

[0122] In operations S40 and S45, the punch holder material 112' and the die holder material 116' are fixedly overlapped. Fixing the punch holder material 112' and the die holder material 116' to be fixedly overlapped can be performed by a method such as clamping, bolting, fastening a pin, welding, etc., but is not limited to these methods. Figure 11B Fixing using a clamp 132 is shown, and Figure 11C Fixing by a bolt 134, fixing by a fastening pin 136, and fixing by welding 138 are shown together.

[0123] In operation S50, the side surfaces of the punch holder material 112' and the die holder material 116' overlapped with each other are polished at the same time. Since the side surfaces of the assembly in which the punch holder material 112' and the die holder material 116' are fixedly overlapped are polished at the same time, the side surfaces of each of the materials 112', 116' are matched with each other in terms of size. Since the simultaneous polishing of the side surfaces can be performed on all the side surfaces of the punch holder material 112' and the die holder material 116', all the side surfaces of the punch holder material 112' and the die holder material 116' can be aligned with each other, and the areas of the materials can be substantially the same. In an embodiment, the side surface of the punch holder material 112' and the side surface of the die holder material 116' can be flush when polished at the same time.

[0124] In operation S60, a center point 142 of the overlap of the punch holder material 112' and the die holder material 116' whose side surfaces are polished is set. The position of the center point 142 can be set based on the side surfaces of the punch holder material 112' and the die holder material 116' that are polished at the same time. The center point 142 can be set as a hole having any diameter or a mark having any shape. The hole can be formed by a wire processing device, and the mark can be formed by a laser marking device. Figure 11D The center point 142 set in the form of a hole is shown.

[0125] In operation S70, a common reference hole 140 is machined through the punch holder material 112' and the die holder material 116' which are fixedly overlapped at a position spaced apart from the center point 142 by a predetermined distance. Figure 11E The reference hole 140 is shown. Four reference holes 140 can be formed, but the number of reference holes 140 can vary. Since the reference hole 140 is formed by passing through the punch holder material 112' and the die holder material 116' which are fixedly overlapped as shown, Figure 11D Since the reference hole 140 of the punch holder material 112' and the reference hole 140 of the die holder material 116' now become references for machining positions of other machined target elements (e.g., recesses, holes, etc.) as the punch holder material 112' and the die holder material 116' which are fixedly overlapped are shown,

[0126] In operation S80, with respect to the machined reference hole 140, recesses 126, 128, 132, and 134 in which punches and dies are installed are machined in the punch holder material 112' and the die holder material 116'. Other machined target elements (e.g., bolt holes or various functional holes) can also be machined based on the reference hole 140. Figure 11E The punch holder 112 completed by machining the punch installation recesses 126, 128, and the guide pillar coupling hole 124 is shown. Similarly, the die holder 116 can also be completed.

[0127] Since the side surface of the assembly in which the punch holder material 112' and the die holder material 116' are fixedly overlapped is simultaneously polished, and the punch recesses, the die recesses, and other machined target elements are machined based on the reference hole 140 set as a reference which is machined based on the center point 142, it is possible to minimize the position deviation occurrence rate of the punch holder 112 and the die holder 116.

[0128] Figure 12 is a flowchart showing a method of manufacturing a punch holder 112 and a die holder 116 according to an embodiment of the disclosure. Figures 13A-13E is shown a punch holder 112 and a die holder 116 manufactured according to the process of Figure 12 is shown a punch holder 112 and a die holder 116 manufactured according to the process of

[0129] In operations S10 and S20, a punch holder material 112' for manufacturing a punch holder and a die holder material 116' for manufacturing a die holder are prepared. Figure 13A The punch holder material 112' and the die holder material 116' are shown.

[0130] In operations S15 and S25, the punch holder material 112' and the die holder material 116' are fixedly overlapped at a position spaced apart from the center point 142 by a predetermined distance. Figure 10The different shown, in the punch holder material 112' prepared, the rough cutting (or roughing) punch mounting recesses 126', 128', and in the die holder material 116' rough cutting die mounting recesses 132', 134' are. Figure 13A The rough cut recesses 126', 128', 132', and 134' are shown. S30 ~ S70 are substantially the same as Figure 10 the case.

[0131] In operation S30, before the punch holder material 112' and the die holder material 116' are overlapped, the overlapping surfaces of each material can be polished.

[0132] In operations S40 and S45, the punch holder material 112' and the die holder material 116' are fixedly overlapped.

[0133] In operation S50, the side surfaces of the punch holder material 112' and the die holder material 116' overlapped with each other are polished at the same time.

[0134] In operation S60, a center point 142 of the overlap of the punch holder material 112' and the die holder material 116' whose side surfaces are polished is set.

[0135] In operation S70, a common reference hole 140 passing through the punch holder material 112' and the die holder material 116' overlapped with each other is machined at a position spaced apart from the center point 142 by a predetermined distance.

[0136] In operation S90, the recesses 126, 128, 132, and 134 rough cut in the punch holder material 112' and the die holder material 116' are finished based on the machined reference hole 140. In operation S95, other machined target elements (for example, bolt holes or various function holes) can also be machined based on the reference hole 140. Figure 13E The punch holder 112 completed by machining the punch mounting recesses 126, 128, and the guide pillar coupling hole 124 is illustrated. Similarly, the die holder 116 can also be completed.

[0137] Figure 14 A die assembly for cutting an electrode plate of a secondary battery according to an embodiment of the disclosure is illustrated, the die assembly including a punch holder 112 and a die holder 116 manufactured by a method of manufacturing a punch holder and a die holder of a die assembly for cutting an electrode plate of a secondary battery.

[0138] The die assembly for cutting an electrode plate of a secondary battery includes a punch holder and a die holder manufactured by Figure 10 , Figures 11A-11E , Figure 12 and Figures 13A-13Epunch support 112 and the die support 116. The punch support 112 can be supported by the upper slide 114, and the die support 116 can be supported by the lower slide 118. The upper slide 114 and the lower slide 118 can be connected to the main column 120a, and the punch support 112 and the die support 116 can be connected to the sub-column 120b. The pin 144 can be inserted into the reference hole 140 (see Figure 11D and Figure 13D ) of the punch support 112 (see Figure 11D and Figure 13D ) of the die support 116. The pin 144 can be an alignment pin that aligns the punch support 112 with the die support 116.

[0139] Since the side surfaces of the punch support 112 and the die support 116 are simultaneously polished while being fixedly overlapped with each other, the punch support 112 and the die support 116 have surfaces that are aligned with each other. The punch support 112 and the die support 116 have a common center point 142 that is set at the same position with respect to the simultaneously polished side surfaces, and have common reference holes 140 that are processed based on the center point 142.

[0140] A method of manufacturing a die assembly for cutting an electrode plate of a secondary battery can include manufacturing a punch support and a die support by the above-described method of manufacturing a punch support and a die support, assembling the manufactured punch support and the die support, and connecting the punch support and the die support to an upper slide and a lower slide, respectively.

[0141] The assembling of the manufactured punch support and the die support can include mounting a punch on the punch support and mounting a die on the die support, connecting the punch support and the die support with a sub-column, and inserting a pin into a reference hole of the punch support and a reference hole of the die support.

[0142] Since the punch recess, the die recess, and other target parts for processing are processed based on the reference holes, it is possible to minimize the deviation occurrence rate between the punch support and the die support. Accordingly, it is possible to maintain the constant positional accuracy of the punch and the die of the cutting die assembly, such as a cut of an electrode plate, thereby minimizing the distortion of the parallelism of the die assembly, and minimizing problems such as the occurrence of burrs during the processing of the electrode plate and damage to the punch and the die.

[0143] Since it is an important factor to consider that 1:1 assembly (i.e., having "zero" gap) of the punch and the die is achieved in the cutting die assembly, it is possible to easily maintain the gap between the punch and the die, and minimize the amount of pushing of the punch support by the pressure of the lateral load generated at the time of pressing, by improving the accuracy of the punch support recess and the die support recess on which the punch and the die are assembled, respectively.

[0144] Conventionally, when assembling a punch holder and a die holder, the assembly of the punch holder and the die holder has inevitably involved human error due to low dimensional accuracy of the punch holder and the die holder. In contrast, the present disclosure can reduce a life deviation of a punch and a die by setting a reference hole at an accurate position to convert a dimension into data and manage the data, thereby extending a life of an entire die assembly.

[0145] The present disclosure can be applied not only to a notch die assembly of an electrode plate of a secondary battery, but also to a die assembly for other purposes and functions requiring position accuracy of a punch and a die.

[0146] While the present disclosure has been described above with respect to embodiments thereof, the present disclosure is not limited thereto. Those skilled in the art can make various modifications and variations thereto within the spirit of the present disclosure.

Claims

1. A mold assembly, comprising: A punch holder includes a first recess configured to receive a punch for making cuts in the electrode plates of a secondary battery. as well as A mold support includes a second recess configured to receive a mold for making cuts in the electrode plate placed on the second recess. The side surfaces of each of the punch holder and the die holder are aligned with each other. Each of the punch holder and the die holder has a center point at the same location, and Each of the punch holder and the die holder has a reference hole at the same location spaced apart from the center point.

2. The mold assembly of claim 1, wherein the punch holder and the mold holder are fixedly overlapped, and wherein the side surfaces of each of the punch holder and the mold holder are flush when polished simultaneously.

3. The mold assembly of claim 1, wherein the position of the center point of each of the punch holder and the mold holder is based on the side surface of each of the punch holder and the mold holder.

4. The mold assembly of claim 1, wherein the first recess is machined based on the reference hole of the punch holder, and The second recess is machined based on the reference hole of the mold support.

5. The mold assembly according to claim 1, further comprising a pin inserted into the reference hole of the punch holder and the reference hole of the mold holder.

6. A method for manufacturing a punch holder and a die holder for a die assembly for cutting electrode plates of a secondary battery, the method comprising: The punch holder and the mold holder are fixedly overlapped; Simultaneously polish the side surfaces of each of the punch holder and the mold holder; Set the center point of each of the punch holder and the mold holder; as well as A reference hole is generated at a location spaced apart from the center point, passing through each of the punch holder and the die holder.

7. The method of claim 6, further comprising: Before the fixed overlap, the corresponding surfaces of the punch holder and the die holder that will come into contact are polished.

8. The method of claim 6, wherein the setting includes setting the center point based on the simultaneously polished side surfaces of each of the punch holder and the die holder.

9. The method of claim 6, further comprising generating a recess in each of the punch holder and the die holder based on the reference hole.

10. The method of claim 6, further comprising: Before the fixed overlap, each of the punch holder and the die holder is rough-machined into a recess.

11. The method of claim 6, wherein the fixed overlap comprises using clamps, bolts, or welding to secure the punch holder and the die holder.

12. A method for manufacturing a mold assembly for cutting out electrode plates of a secondary battery, the method comprising: Make the punch holder and the die holder overlap in a fixed manner; Simultaneously polish the side surfaces of each of the punch holder and the mold holder; Set the center point of each of the punch holder and the mold holder; A reference hole is created at a position spaced apart from the center point, passing through the punch holder and the mold holder; as well as The punch holder and the mold holder are assembled via the reference hole.

13. The method of claim 12, further comprising: Before the fixed overlap, the corresponding surfaces of the punch holder and the die holder that will come into contact are polished.

14. The method of claim 12, wherein the setting includes setting the center point based on the simultaneously polished side surfaces of each of the punch holder and the die holder.

15. The method of claim 12, further comprising generating a recess in each of the punch holder and the die holder based on the reference hole.

16. The method of claim 12, further comprising: Before the fixed overlap, each of the punch holder and the die holder is rough-machined into a recess.

17. The method of claim 12, wherein the fixed overlap comprises using clamps, bolts, or welding to secure the punch holder and the die holder.

18. The method of claim 12, wherein the assembly includes inserting a pin into the reference hole of the punch holder and the reference hole of the die holder.

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