Pouch-type secondary battery, pressure device for same, and method for manufacturing same

Abstract

Aspects of embodiments of the present disclosure relate to a pouch-type secondary battery, an extrusion device for the pouch-type secondary battery, and a method for manufacturing the pouch-type secondary battery. A pouch-type secondary battery includes: an electrode assembly including a stack of unit cells; each unit monomer comprises a first electrode plate, a first electrode lug on the first electrode plate, a second electrode plate, a second electrode lug on the second electrode plate and a diaphragm between the first electrode plate and the second electrode plate; the first tape is attached to at least one side surface of the electrode assembly perpendicular to a stacking direction of the stacked body of the unit cells. The first tape is located at a corner portion of the electrode assembly where the first electrode tab or the second electrode tab is located, and the corner portion is located at an inclined region where the thickness of the electrode assembly is reduced.

Description

Technical Field

[0001] Embodiments of this disclosure relate to a pouch-type secondary battery, a compression device for the pouch-type secondary battery, and a method for manufacturing the pouch-type secondary battery. Background Technology

[0002] Unlike primary batteries, which are not designed to be (re)charged, secondary (or rechargeable) batteries are designed to be discharged and recharged. Low-capacity secondary batteries are used in portable small electronic devices such as smartphones, feature phones, laptops, digital cameras, and camcorders, while high-capacity secondary batteries are widely used as power sources to drive motors in hybrid and electric vehicles and to store electricity (e.g., household and / or utility-scale power storage). A secondary battery typically includes an electrode assembly containing positive and negative electrodes, a housing that houses the electrode assembly, and electrode terminals connected to the electrode assembly.

[0003] The manufacturing process of secondary batteries can be broadly divided into electrode processes, assembly processes, activation processes, and formation processes. The activation or formation process imparts electrical characteristics to the secondary batteries manufactured through the assembly process and performs defect checks after stable operation. Following the assembly process, the secondary battery can be charged to provide its electrical characteristics and undergoes repeated aging processes to ensure that the positive and negative electrode materials are adequately impregnated with the electrolyte. Pouch cells may undergo a degassing process, if necessary or required, to remove internal gases before reaching the desired battery performance. The final cell is inspected for internal resistance (IR) and open-circuit voltage (OCV).

[0004] The information disclosed in this background section is intended to enhance the understanding of the background art of this disclosure, and therefore may contain information that does not constitute related (or prior art). Summary of the Invention

[0005] The process of activating a secondary battery through heating, extrusion, and charging during the formation process is called the thermo-pressurized charging (HPC) process. However, problems may occur with pouch cells: during the charging and discharging processes in the HPC process, or throughout the life of the pouch cell, side reactions may occur at the ends where the electrode terminals are connected.

[0006] One or more embodiments of this disclosure may relate to pouch-type secondary batteries, extrusion apparatus for pouch-type secondary batteries, and methods for manufacturing pouch-type secondary batteries.

[0007] However, the technical problems to be solved by this disclosure are not limited to the above-mentioned problems, and those skilled in the art will clearly understand, through the following description of this disclosure, other problems not mentioned herein and the aspects and features of these problems that this disclosure will solve.

[0008] According to one or more embodiments of this disclosure, a pouch-type secondary battery includes: an electrode assembly and a first strip. The electrode assembly includes a stack of individual cells. Each individual cell includes a first electrode plate, a first electrode tab on the first electrode plate, a second electrode plate, a second electrode tab on the second electrode plate, and a separator between the first and second electrode plates. The first strip is attached to at least one side of the electrode assembly perpendicular to the stacking direction of the individual cells. The first strip is located at a corner portion of the electrode assembly, where the first or second electrode tab is located, and the corner portion is located at an inclined region where the thickness of the electrode assembly decreases.

[0009] In one embodiment, the inclined region may be the portion of the first electrode mixture on the first electrode plate or the portion of the second electrode mixture on the second electrode plate where the thickness decreases.

[0010] In one embodiment, the thickness of the first electrode mixture portion of the first electrode plate or the second electrode mixture portion of the second electrode plate in the inclined region may be less than the thickness in the region other than the inclined region.

[0011] In one embodiment, the first strip may be attached to the front side of the electrode assembly perpendicular to the stacking direction and the rear side of the electrode assembly opposite to the front side in the stacking direction.

[0012] In one embodiment, the first electrode tab may include a stack of first electrode tab groups, and a first lead tab may be connected to the first electrode tab group. The second electrode tab may include a stack of second electrode tab groups, and a second lead tab may be connected to the second electrode tab group. The first lead tab and the second lead tab may be located in the same direction as each other in the electrode assembly.

[0013] In one embodiment, the first electrode tab may include a stack of first electrode tab groups, and a first lead tab may be connected to the first electrode tab group. The second electrode tab may include a stack of second electrode tab groups, and a second lead tab may be connected to the second electrode tab group. The first lead tab and the second lead tab may be located in opposite directions of the electrode assembly.

[0014] In one embodiment, the first strip may include an insulating material.

[0015] According to one or more embodiments of this disclosure, a compression device for a pouch-type secondary battery includes: a first plate and a second plate opposite to the first plate; an insert having opposite ends respectively connected to upper portions of the first plate and upper portions of the second plate, and located between the first plate and the second plate; and a second strip attached to the insert. The second strip is attached to a corner portion of the pouch-type secondary battery disposed on the insert, the corner portion being where the lead terminals of the pouch-type secondary battery are located, and the corner portion being located at an inclined region where the thickness of the electrode assembly decreases.

[0016] In one embodiment, the pouch-type secondary battery may include: an electrode assembly and a first strip. The electrode assembly includes a stack of individual cells, and each individual cell includes: a first electrode plate, a first electrode tab on the first electrode plate, a second electrode plate, a second electrode tab on the second electrode plate, and a separator between the first and second electrode plates. The first strip is attached to at least one side of the electrode assembly perpendicular to the stacking direction of the stack of individual cells. The first strip may be located at a corner of the electrode assembly, where either the first or second electrode tab is located.

[0017] In one embodiment, the second strip may cover the entire area of ​​the first strip.

[0018] In one embodiment, one end of the second strip may be located on the upper side of the first strip.

[0019] In one embodiment, the lead terminal may be exposed to the outside of the insert on which the pouch-type secondary battery is placed.

[0020] In one embodiment, the lead wire tab may be exposed in the lateral direction of the insert.

[0021] In one embodiment, the lead wire tab may be exposed in the upward direction of the insert.

[0022] In one embodiment, the inclined region may be the portion of the first electrode mixture on the first electrode plate or the portion of the second electrode mixture on the second electrode plate where the thickness decreases.

[0023] In one embodiment, the thickness of the first electrode mixture portion of the first electrode plate or the second electrode mixture portion of the second electrode plate in the inclined region may be less than the thickness in the region other than the inclined region.

[0024] In one embodiment, the first and second strips may include pressure-resistant or heat-resistant materials.

[0025] According to one or more embodiments of this disclosure, a method for manufacturing a pouch-type secondary battery includes: manufacturing an electrode assembly by stacking unit cells, each unit cell including: a first electrode plate, a first electrode tab on the first electrode plate, a second electrode plate, a second electrode tab on the second electrode plate, and a separator between the first and second electrode plates; attaching a first strip to at least one side of the electrode assembly perpendicular to the stacking direction of the unit cells; assembling the pouch-type secondary battery including the electrode assembly and the first strip; and extruded the pouch-type secondary battery using an extrusion device. The extrusion device includes: a first plate and a second plate opposite to the first plate; an insert having opposite ends respectively connected to the upper portions of the first and second plates and located between the first and second plates; and a second strip attached to the insert. The first strip is located at a corner portion of the electrode assembly, where the first or second electrode tab is located, at an inclined region where the thickness of the electrode assembly decreases, and the second strip is attached to a position corresponding to the first strip.

[0026] In one embodiment, the second strip may cover the entire area of ​​the first strip.

[0027] In one embodiment, one end of the second strip may be on the upper side of the first strip.

[0028] According to some embodiments of this disclosure, the flatness of the corner portion of the end portion at the electrode terminal connection can be improved by attaching an electrode assembly to the pouch cell, thereby suppressing side reactions caused by electrolyte buildup during charging and discharging processes or during the life of the pouch cell.

[0029] According to some embodiments of this disclosure, the flatness of the corner portion of the end portion at the electrode terminal connection can be improved by modifying the structure of the extrusion device in the HPC process, thereby suppressing side reactions caused by electrolyte accumulation during charging and discharging processes or during the life of the pouch cell.

[0030] According to some embodiments of this disclosure, the existing manufacturing process for pouch-type secondary batteries may further include a process for attaching a tape (e.g., a process for attaching the tape only), which makes the manufacturing process easily improveable.

[0031] However, the aspects and features of this disclosure are not limited to those described above, and other aspects and features not mentioned will be clearly understood by those skilled in the art from the detailed description described below. Attached Figure Description

[0032] The accompanying drawings illustrate embodiments of the present disclosure and, together with the detailed description of the present disclosure, further describe aspects and features of the present disclosure. Therefore, the present disclosure should not be construed as limited to the drawings:

[0033] Figure 1 A perspective view illustrating a pouch-type secondary battery according to an embodiment of the present disclosure;

[0034] Figure 2 A longitudinal cross-sectional view of a portion of an electrode assembly according to an embodiment of the present disclosure is shown;

[0035] Figure 3 An example of the side reaction process of a pouch-type secondary battery according to an embodiment of the present disclosure;

[0036] Figure 4 An electrode assembly according to an embodiment of the present disclosure is illustrated;

[0037] Figure 5 An electrode assembly according to an embodiment of the present disclosure is illustrated;

[0038] Figure 6 A perspective view illustrating an extrusion apparatus according to an embodiment of the present disclosure;

[0039] Figure 7 Example Figure 6 An enlarged perspective view of the paper insert in area A;

[0040] Figure 8 This illustrates the positional relationship between the first and second strips according to an embodiment of the present disclosure;

[0041] Figure 9 This illustrates the positional relationship between the first and second strips according to an embodiment of the present disclosure;

[0042] Figure 10 A longitudinal cross-sectional view of an extrusion apparatus according to an embodiment of the present disclosure is shown; and

[0043] Figure 11 A flowchart illustrating a method for manufacturing a pouch-type secondary battery according to an embodiment of the present disclosure. Detailed Implementation

[0044] Some embodiments of this disclosure will be described in detail below with reference to the accompanying drawings. The terms or words used in this specification and claims should not be construed as having a general or dictionary meaning, but should be interpreted as consistent with the technical spirit of this disclosure, based on the principle that the inventor is capable of being his / her own lexicographer to appropriately define the terms and concepts in order to best describe his / her invention.

[0045] The embodiments described in this specification and the configurations shown in the accompanying drawings are only some of the embodiments of this disclosure and do not represent all the technical spirit, aspects, and features of this disclosure. Therefore, it should be understood that various equivalents and modifications that can replace or modify the embodiments described herein may exist at the time of filing this application.

[0046] It will be understood that when a component or layer is described as being "on," "connected to," or "attached to" another component or layer, it can be directly on, connected to, or attached to the other component or layer, or one or more intermediate components or layers may be present. When a component or layer is described as being "directly" on, directly connected to, or directly attached to another component or layer, no intermediate components or layers are present. For example, when a first component is described as being "attached" or "connected" to a second component, the first component can be directly attached to or connected to the second component, or the first component can be indirectly attached to or connected to the second component via one or more intermediate components.

[0047] In the accompanying drawings, the dimensions of various elements, layers, etc., may be enlarged for clarity of illustration. The same reference numerals indicate the same elements. As used herein, the term “and / or” includes any and all combinations of one or more associated listed items. Furthermore, the use of “may” in describing embodiments of this disclosure refers to “one or more embodiments of this disclosure.” Expressions such as “at least one of…” and “any one of…” preceding / following the list of elements modify the entire list of elements, but not individual elements in the list. When phrases such as “at least one of A, B, and C,” “at least one of A, B, or C,” “at least one selected from the group of A, B, and C,” or “at least one selected from A, B, and C” are used to specify a list of elements A, B, and C, the phrase may refer to any and all suitable combinations or subsets of A, B, and C, such as A, B, C, A and B, A and C, B and C, or A and B and C. As used herein, the term “use” may be considered synonymous with the term “utilize.” As used herein, the terms “roughly,” “approximately,” and similar terms are used as approximate terms rather than terms of degree and are intended to account for the inherent variations in measurements or calculations that would be apparent to a person skilled in the art.

[0048] It will be understood that while the terms first, second, third, etc., may be used to describe various elements, components, regions, layers, and / or segments, these elements, components, regions, layers, and / or segments should not be limited by these terms. These terms are used to distinguish one element, component, region, layer, or segment from another element, component, region, layer, or segment. Therefore, without departing from the teachings of the exemplary embodiments, the first element, component, region, layer, or segment discussed below may be referred to as the second element, component, region, layer, or segment.

[0049] For ease of description, this document uses spatial relative terms such as “below,” “under,” “down,” “above,” and “up” to describe the relationship between one element or feature and another element or feature as shown in the figure. It should be understood that spatial relative terms are intended to include different orientations of the device in use or operation, in addition to the orientation depicted in the figure. For example, if the device in the figure is flipped, an element described as “below” or “under” other elements or features can be oriented; an element described as “below” or “under” other elements or features can be oriented; and “above” or “up” other elements or features can include both above and below orientations. The device can be oriented in other ways (rotated 90 degrees or in other orientations), and the spatial relative descriptors used herein should be interpreted accordingly.

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

[0051] Furthermore, any numerical ranges disclosed and / or enumerated herein are intended to include all subranges with the same numerical precision contained within the enumerated ranges. For example, the range “1.0 to 10.0” is intended to include all subranges between the enumerated minimum value of 1.0 and the enumerated maximum value of 10.0 (and inclusive of both), i.e., a minimum value equal to or greater than 1.0 and a maximum value equal to or less than 10.0, such as 2.4 to 7.6. Any maximum numerical limit enumerated herein is intended to include all lower numerical limits contained therein, and any minimum numerical limit enumerated in this specification is intended to include all higher numerical limits contained therein. Therefore, the applicant reserves the right to modify this specification, including the claims, to expressly enumerate any subranges contained within the scope expressly enumerated herein. All such ranges are intended to be inherently described in this specification such that modifications made to expressly enumerate any such subranges will comply with the applicable requirements.

[0052] Referring to two compared elements, features, etc., as “identical” may mean that they are “substantially identical.” Therefore, the phrase “substantially identical” can include cases with deviations considered low in the art, such as 5% or less. Furthermore, when a parameter is said to be consistent in a given region, this may mean that it is consistent in terms of its mean.

[0053] Throughout this specification, unless otherwise stated, each element may be singular or plural.

[0054] Placing any element "above (or below)" or "above (or below)" another element may mean that the arbitrary element can be positioned to contact the upper (or lower) surface of the element, and other elements may also be positioned between the element and any element positioned on (or below) the element.

[0055] Furthermore, it will be understood that when a component is referred to as “connected,” “linked,” or “attached” to another component, the components can be directly “connected,” “linked,” or “attached” to each other, or another component can be “between” the components.

[0056] Throughout this specification, unless otherwise stated, when “A and / or B” is stated, it means A, B, or A and B. In other words, “and / or” includes any or all combinations of the listed items. Unless otherwise indicated, when “C to D” is stated, it means greater than or equal to C and less than or equal to D.

[0057] The terminology used in this specification is for describing embodiments of this disclosure and is not intended to limit this disclosure.

[0058] In this disclosure, for clarity of illustration, the dimensions and relative dimensions of layers and regions shown in the accompanying drawings may be enlarged. In other words, the dimensions shown in the drawings are provided for ease of illustration, and therefore, this disclosure is not limited thereto. Furthermore, throughout this specification, the same reference numerals consistently designate the same elements.

[0059] Figure 1 A perspective view illustrating a pouch-type secondary battery according to an embodiment of the present disclosure is shown. The pouch-type secondary battery 100 may include an electrode assembly 110 and a housing 140 housing the electrode assembly 110. The housing 140 may be in the form of a pouch. In other words, the housing 140 may have a pouch shape.

[0060] refer to Figure 1 The electrode assembly 110 may include a first electrode plate 114, a second electrode plate 120, and a diaphragm 118 located therebetween. The first electrode plate 114 may be a positive electrode plate, and the second electrode plate 120 may be a negative electrode plate. As another example, the first electrode plate 114 may be a negative electrode plate, and the second electrode plate 120 may be a positive electrode plate. In the following description, for ease of illustration, the first electrode plate 114 may be described in more detail in the context of a positive electrode plate, and the second electrode plate 120 may be described in more detail in the context of a negative electrode plate, but this disclosure is not limited thereto.

[0061] The first electrode plate 114 may include a first electrode tab 116 electrically connected to an uncoated portion of the first electrode. The second electrode plate 120 may include a second electrode tab 122 electrically connected to an uncoated portion of the second electrode. The first electrode tab 116 and the second electrode tab 122 may be soldered to the first lead tab 126 and the second lead tab 124, respectively, and thus may be electrically connected to the outside. A tab film for insulating from the housing 140 may be attached to the first lead tab 126 and the second lead tab 124.

[0062] When the electrode assembly 110 is housed within the housing 140, the housing 140 can be sealed by bringing the sealing portions at its edges into contact with each other. The sealing can be achieved using a diaphragm between the sealing portions. For example... Figure 1 As shown, the terminal block film can be attached to each of the first electrode terminal block 116 and the second electrode terminal block 122.

[0063] The sealing portion of the housing 140 can be formed of a hot-melt material and can have a suitable structure for achieving a seal by bonding the hot-melt layers together. Since hot-melt materials can typically have weak adhesion to metals, a thin-film form of the electrode tab can be attached to the electrode tab and fused to the housing 140.

[0064] refer to Figure 1 Electrode assembly 110 can be formed by stacking unit cells 112 on top of each other. Unit cell 112 may include a first electrode plate 114 having a first electrode tab 116 formed thereon, a second electrode plate 120 having a second electrode tab 122 formed thereon, and a diaphragm 118 between the first electrode plate 114 and the second electrode plate 120. Thus, in one embodiment, electrode assembly 110 may be a stacked assembly. The electrode plates and electrode tabs may be formed in plate or film shapes. Electrode assembly 110 may correspond to a Z-stacked electrode assembly in which the first electrode plate 114 and the second electrode plate 120 are inserted on opposite sides of the diaphragm 118 folded into a Z-stack. However, the shape of the electrode assembly is not particularly limited thereto, and in other embodiments, the electrode assembly may have any suitable shape required or desired.

[0065] Multiple electrode assemblies 110 can be stacked such that their long sides are adjacent to each other and can be stored separately inside the housing 140. The number of electrode assemblies is not particularly limited in this disclosure.

[0066] The first electrode tab 116 and the second electrode tab 122 may be located on the same side of the electrode assembly 110. For example, the first electrode tab 116 and the second electrode tab 122 may be formed on the same side of the electrode assembly 110, parallel to or substantially parallel to the stacking direction of the unit cells 112 of the electrode assembly 110. In other words, the first electrode tab 116 and the second electrode tab 122 may extend from the same side of the electrode assembly in a direction perpendicular to or substantially perpendicular to the stacking direction of the unit cells 112. In some embodiments, the first electrode tab 116 and the second electrode tab 122 may be located on different sides of the electrode assembly. For example, the first electrode tab 116 may be located on the left side of the electrode assembly 110, on one of the sides parallel to or substantially parallel to the stacking direction of the unit cells 112 of the electrode assembly 110, and the second electrode tab 122 may be located on the right side of the electrode assembly 110. For ease of illustration, left and right are based on... Figure 1 The secondary battery shown is described, but its position can be modified in various ways as needed or desired, for example, when the secondary battery is rotated left and right or up and down.

[0067] The electrode assembly 110 can be housed together with the electrolyte in the housing 140. Furthermore, in the electrode assembly 110, the first lead terminal 126 and the second lead terminal 124 can be respectively connected to the first electrode terminal 116 of the first electrode plate 114 and the second electrode terminal 122 of the second electrode plate 120. The first current collector and the second current collector can be soldered and connected to the first lead terminal 126 and the second lead terminal 124, respectively.

[0068] According to embodiments of this disclosure, the first strip 130 may be attached to the front side of the electrode assembly 110, which is perpendicular or substantially perpendicular to the stacking direction of the unit cells 112 of the electrode assembly 110 as described above. In other words, the front side of the electrode assembly 110 may be a side extending in a direction perpendicular or substantially perpendicular to the stacking direction of the unit cells 112 of the electrode assembly 110. For example, on the front side of the electrode assembly 110, which is perpendicular or substantially perpendicular to the stacking direction of the unit cells 112 of the electrode assembly 110, the first strip 130 may be attached to a corner portion 138 of the electrode assembly 110 in a direction perpendicular or substantially perpendicular to the stacking direction of the unit cells 112 of the electrode assembly 110, where the corner portion 138 is located, is the location of the first electrode tab 116 or the second electrode tab 122. In some embodiments, a first strip 130 may be attached to a corner portion 138 of the electrode assembly 110 in a direction perpendicular or substantially perpendicular to the stacking direction of the unit cells 112 of the electrode assembly 110, where the corner portion 138 is located, which is the location of the first electrode tab 116 or the second electrode tab 122. That is, the first strip 130 may be attached to at least one side (e.g., at least one of the front and rear sides) of the electrode assembly 110 perpendicular to the stacking direction of the stack of unit cells 112. The front or rear side of the electrode assembly 110 distinguishes the two sides of the electrode assembly 110 perpendicular or substantially perpendicular to the stacking direction of the unit cells 112 (e.g., the two sides extending in a direction perpendicular or substantially perpendicular to the stacking direction) and does not necessarily refer to the surface facing the front or rear side. The front or rear side of the electrode assembly 110 may be referred to as the first or second side of the electrode assembly 110 that is perpendicular or substantially perpendicular to the stacking direction.

[0069] The width of the first band 130 can correspond to the width of the electrode assembly 110. The first band 130 will be described in more detail below.

[0070] Figure 2 A longitudinal cross-sectional view of a portion of an electrode assembly according to an embodiment of the present disclosure is shown. Figure 2 An example of a structure for stacking individual units is shown, and the locations of inclined regions A and A' and normal region B are illustrated.

[0071] The first electrode plate 114 may include a first electrode current collector plate 114a formed of a metal foil such as aluminum or an aluminum alloy, a first electrode mixture portion 114b formed thereon, and a first uncoated portion as a region of the first electrode mixture portion 114b that is not coated. A first electrode tab 116 may be integrally formed with the first uncoated portion, or may be connected to the first uncoated portion by welding or the like. The first electrode tab 116 may serve as a path for current flow between the first electrode plate 114 and the current collector. In some examples, the first electrode tab 116 may be formed by pre-cutting the first electrode plate 114 to protrude to one side during manufacturing, and may protrude further to that side than a diaphragm 118 that is not separately cut.

[0072] The second electrode plate 120 can be formed by coating a second electrode mixture portion 120b, such as graphite or carbon, onto a second electrode current collector plate 120a formed of a metal foil such as copper, a copper alloy, nickel, or a nickel alloy, and may include a second uncoated portion as a region where the second electrode mixture material 120b is not coated. The second electrode tab 122 may be integrally formed with the second uncoated portion, or may be connected to the second uncoated portion by welding or the like. The second electrode tab 122 can serve as a path for current flow between the second electrode plate 120 and the current collector. In some examples, the second electrode tab 122 may be formed by pre-cutting the second electrode plate 120 to protrude to one side during the manufacture of the second electrode plate 120, and may protrude further to one side than a diaphragm 118 that is not separately cut.

[0073] exist Figure 2 In the diagram, the first electrode plate 114 and the second electrode plate 120 are shown to have the same or substantially the same dimensions, but this disclosure is not limited thereto, and the two electrode plates may have different dimensions. Because the dimensions of the two electrode plates may differ, overhangs may occur. For example, the area of ​​the negative electrode plate may be larger than the area of ​​the positive electrode plate.

[0074] Figure 2 Examples of stacked structures of the stacked electrode assembly 110 according to embodiments are illustrated schematically, but this disclosure is not limited to the number, size, or structure of the electrode plates. For example, a first electrode mixture portion 114b may be applied to an opposite side or one side of a first electrode current collector plate 114a. Furthermore, a second electrode mixture portion 120b may be applied to an opposite side or one side of a second electrode current collector plate 120a. The outermost portion of the electrode assembly 110 may terminate at either the first electrode current collector plate 114a or the second electrode current collector plate 120a.

[0075] When the electrode active material used to form the electrode mixture portion is applied to the electrode current collector plate, due to the surface tension of the electrode active material during the process of applying the slurry-like electrode active material, the end of the electrode active material can be applied in an inclined shape relative to the other portions of the electrode active material. Accordingly, the end of the electrode mixture portion (e.g., the first electrode mixture portion 114b and the second electrode mixture portion 120b) can have an inclined shape. Due to the inclined shape of the electrode mixture portion (e.g., the first electrode mixture portion 114b and the second electrode mixture portion 120b), the electrode plate including the electrode mixture portion (e.g., the first electrode plate 114 and the second electrode plate 120) can form inclined regions A and A' at the end of the electrode assembly 110. For example, the end of the electrode assembly 110 can be the region including the boundary between the first uncoated portion and the first electrode mixture portion 114b or the boundary between the second uncoated portion and the second electrode mixture portion 120b. The end of the electrode assembly 110 can be the region where the boundary between the uncoated portion and the electrode mixture portion connects to the first electrode terminal 116 or the second electrode terminal 122.

[0076] refer to Figure 2 The first electrode mixture portion 114a of the first electrode plate 114 or the second electrode mixture portion 120b of the second electrode plate 120 in the inclined regions A and A' (e.g., belonging to inclined regions A and A') may have a reduced thickness compared to the thickness in the normal region B, which is a region other than the inclined regions A and A'. The inclined regions A and A' may correspond to the regions where the thickness of the electrode assembly is reduced.

[0077] In one embodiment, in the electrode assembly 110 including the inclined regions A and A' as described above, the thickness of the electrode assembly 110 at the portion where the first electrode tab 116 or the second electrode tab 122 is located may be thinner than the thickness in the normal region B.

[0078] Furthermore, in a stacking method for stacking unit cells 112 including a first electrode plate 114, a diaphragm 118, and a second electrode plate 120, time (e.g., a fixed or predetermined time) may be used, for example, during the stacking of the first electrode plate 114 and the diaphragm 118 or during the stacking of the diaphragm 118 and the second electrode plate 120. During this time, the diaphragm 118 may be raised. Due to the raising of the diaphragm 118, the pore space between the electrode plates (e.g., the first electrode plate 114 and the second electrode plate 120) and the diaphragm 118 may widen.

[0079] Figure 3 The side reaction process of a pouch-type secondary battery according to an embodiment of the present disclosure is illustrated. Figure 3This is an illustration of the process of manufacturing an electrode assembly 110 by stacking individual unit cells and then manufacturing a pouch-type secondary battery 100 after being housed in a housing 140.

[0080] With the housing 140 housing the electrode assembly 110 sealed and electrolyte injected, the pore space between the separator and the electrode plates can be filled with electrolyte. However, as described above, electrolyte may accumulate at the ends of the electrode assembly, which are the locations of the first electrode tab 116 or the second electrode tab 122 of the electrode assembly 110. More specifically, stagnation may occur when electrolyte fills the relatively wider pore space located in the inclined region 128. As a result, undesirable side reactions may occur on the surface of the electrode plates during the charging and discharging process of the pouch cell 100.

[0081] Accordingly, in order to suppress possible side reactions at the ends of the electrode assembly where the first electrode terminal 116 or the second electrode terminal 122 is located, the corner portions of the electrode assembly 110 can be increased (e.g., as shown in the above reference). Figure 1 The flatness of the corner portion 138, where the first electrode tab 116 or the second electrode tab 122 corresponds to the inclined region 128. According to embodiments of this disclosure, to improve the flatness of the corner portion of the electrode assembly 110, a first strip (e.g., referred to above) can be attached. Figure 1 The first band 130 mentioned above). For example... Figure 3 As shown, the inclined region 128 where side reactions may occur can be formed over the entire width of the electrode assembly 110. Therefore, the width of the first strip can correspond to the width of the electrode assembly 110.

[0082] Figure 4 An electrode assembly according to an embodiment of the present disclosure is illustrated. Figure 4 A front view and a rear view of the electrode assembly 110 according to an embodiment are shown. In the following text, the redundant descriptions described above will not be repeated.

[0083] The first strip 130 attached to the corner portion 138 of the electrode assembly 110 may include an insulating material. For example, the first strip 130 may include at least one of polyimide (PI), polyethylene (PE), or polystyrene (PS). Furthermore, the first strip 130 may have adhesive strength to bond to the front side of the electrode assembly 110.

[0084] refer to Figure 4To improve the flatness of the corner portion 138, the first strip 130 may be located in the sloping region where the thickness of the electrode assembly 110 decreases. The width w1 of the first strip 130 may correspond to the width w2 of the electrode assembly 110. For example, the width w1 of the first strip 130 may be less than or equal to the width w2 of the electrode assembly 110. The width w2 of the electrode assembly 110 may refer to the length between the side angles at the electrode tab joint when the electrode assembly is viewed from above (e.g., in a plan view).

[0085] For example, the width w1 of the first strip 130 may be greater than the width of the electrode tabs. In some embodiments, the width w1 of the first strip 130 may correspond to the width covering two electrode tabs. In some embodiments, the width w1 of the first strip 130 may correspond to the width covering all electrode mixture portions of the electrode assembly 110. In some embodiments, the width w1 of the first strip 130 may correspond to the width covering all areas with boundaries.

[0086] According to an embodiment, the first strip 130 may be attached to the front side of the electrode assembly 110 that is perpendicular or substantially perpendicular to the stacking direction of the unit cells, and to the rear side opposite to the front side. More specifically, as... Figure 4 As shown, the first strip 130 can be attached symmetrically or substantially symmetrically to the front and / or rear sides of the electrode assembly 110 at a position corresponding to the corner portion 138. When the first strip 130 is attached to the front and rear sides, the flatness of the corner portion 138 can be improved.

[0087] According to an embodiment, in a pouch-type secondary battery including an electrode assembly 110 with a first strip 130 attached, a first lead terminal 126 and a second lead terminal 124 may be located in the same direction as the electrode assembly 110. The first lead terminal 126 is connected to a first electrode terminal group in which the first electrode terminals are stacked, and the second lead terminal 124 is connected to a second electrode terminal group in which the second electrode terminals are stacked.

[0088] Figure 5 An electrode assembly according to an embodiment of the present disclosure is illustrated.

[0089] According to an embodiment, in a pouch-type secondary battery including an electrode assembly 110 with a first strip 130 attached, a first lead tab 134 and a second lead tab 136 may be located in opposite directions to each other on the electrode assembly 110. The first lead tab 134 is connected to a first electrode tab group in which the first electrode tabs are stacked, and the second lead tab 136 is connected to a second electrode tab group in which the second electrode tabs are stacked.

[0090] According to an embodiment, in order to improve the flatness of the corner portion 138 of the electrode assembly 110, a first strip 132 can be attached to the corresponding corner portion 138. The corner portion 138 may be located in an inclined region that is a point where the thickness of the electrode assembly decreases (e.g., Figure 2 At the sloping region (128). Reference Figure 5 When the first lead patch 134 and the second lead patch 136 are located in opposite directions of the electrode assembly 110, the corner portion 138 may exist due to the first lead patch 134 and the second lead patch 136, respectively. Accordingly, a plurality of first strips 130 may be attached to a plurality of corner portions 138 located on the front side of the electrode assembly 110 and / or a plurality of corner portions 138 located on the rear side of the electrode assembly 110, respectively. In some embodiments, when the first strips (e.g., a plurality of first strips) 130 are attached symmetrically or substantially symmetrically to opposite ends of the front or rear side, the flatness of the inclined region can be improved.

[0091] Figure 6 A perspective view illustrating an extrusion apparatus according to an embodiment of the present disclosure. Figure 6 An example of a part of an extrusion apparatus used in the formation of a secondary battery.

[0092] The compression device according to some embodiments of this disclosure can be any suitable type of device that compresses the pouch cell from opposite sides. For example, the compression device may include (e.g., a thermo-pressurized charging (HPC) device. Reference Figure 6 The extrusion device 150 may include a first plate 152, a second plate 154 facing the first plate 152 (or opposite to the first plate 152), and a paper insert 156 whose opposite ends are respectively connected to the upper portion 158 of the first plate 152 and the upper portion 160 of the second plate 154 and are located between the first plate 152 and the second plate 154. During the HPC process, the extrusion device may have different models, sizes, and forms, and this disclosure is not limited thereto.

[0093] refer to Figure 6 The extrusion device 150 according to an embodiment may include a plurality of plates (e.g., a first plate 152 and a second plate 154) and insert paper 156. A pouch-type secondary battery may be disposed on one side of the insert paper 156. The extrusion device 150 may have any suitable number, shape, and / or size of plates and insert paper.

[0094] Figure 7 A perspective view illustrating an extrusion apparatus according to an embodiment of the present disclosure. Figure 7 Example of a paper insert 156 in a pressing device according to an embodiment of the present disclosure. Figure 7 Example Figure 6 Enlarged perspective view of paper insert 156 in area A.

[0095] According to embodiments of this disclosure, the second strip 170 may be attached to the insert 156 of the compression device for a pouch-type secondary battery. More specifically, the second strip 170 may be attached to a position corresponding to the corner portion 138 of the pouch-type secondary battery 100, the corner portion 138 being the electrode terminals of the pouch-type secondary battery 100 disposed on the insert 156 (e.g., Figure 1 The first electrode terminal 116 or the second electrode terminal 122 is located at the position of the first electrode terminal 116 or the second electrode terminal 122. When the pouch-type secondary battery 100 arranged in this way is compressed, the flatness of the corner portion 138 can be improved.

[0096] refer to Figure 7 The insert 156 may have a side 156a on which the pouch-type secondary battery 100 is disposed and another side 156b opposite to the side 156a. To increase the flatness of the corner portion 138, a second strip 170 may be attached to at least one of the side 156a and the other side 156b opposite to the side 156a of the insert 156.

[0097] In one embodiment, the pouch-type secondary battery 100 can be disposed on one side 156a of the insert 156 of the compression device, such that the lead terminals are exposed outside the insert 156. More specifically, as Figure 7 As shown, the lead wire tabs can be exposed in the lateral direction of the insert 156. Therefore, pressure on the lead wire tabs and terminal portions can be prevented or substantially prevented.

[0098] For example, the first lead connector of the pouch-type secondary battery 100 (e.g., Figure 4 The first lead terminal 126 and the second lead terminal 124 can be positioned in the same direction as each other. In this case, as Figure 7 As shown, the second strip 170 can be attached to the corner portion 138 of the pouch-type secondary battery 100 and / or the first strip (e.g., Figure 4 The first strip 130) corresponds to the position. For example, a second strip 170 can be attached to one side 156a or the other side 156b of the insert 156. The corner portion 138 can be located in the inclined region where the thickness of the electrode assembly decreases.

[0099] For example, the first lead connector of the pouch-type secondary battery 100 (e.g., Figure 5The first lead tab 134 and the second lead tab (e.g., the second lead tab 136) can be located in opposite directions to each other on the electrode assembly. In this case, the size of the insert 156 can be adjusted so that the first and second lead tabs are exposed outside the insert 156. In this case, the second strip can be attached to the corner portion 138 of the pouch-type secondary battery 100 and / or the first strip (e.g., Figure 5 The first band 132) corresponds to the position. For example, two second bands 170 can be attached to one side 156a or the other side 156b of the insert 156. The corner portion 138 can be located in the inclined region where the thickness of the electrode assembly decreases.

[0100] In one embodiment, such as Figure 7 As shown, the pouch-type secondary battery 100, mounted on a compression device, may include an air bladder 142. During charging / discharging and aging processes, gases may be generated due to chemical reactions within the secondary battery. In cylindrical and prismatic secondary batteries, the casing is rigid and has sufficient internal space to contain the gas, but in the pouch-type secondary battery 100, a flexible casing may be used, which may lead to expansion. Therefore, additional processes for containing and removing the gas can be performed, and the air bladder 142 may be included for these additional processes. The air bladder 142 may be exposed to the outside of a plate (e.g., a first plate 152 or a second plate 154).

[0101] In one embodiment, the second band 170 may be connected to the first band as described above (e.g., Figure 4 The first strip 130) is attached together. For example, the second strip 170 may be attached to the insert 156 of the pressing device to correspond to the inclined area (e.g., Figure 2 In the inclined regions A, A', and 128), the thickness of the first electrode mixture portion of the first electrode plate or the second electrode mixture portion of the second electrode plate of the pouch-type secondary battery 100 decreases in these inclined regions. Therefore, the flatness of the corner portions can be improved, and the suppression of side reactions caused by the electrolyte can be enhanced.

[0102] In one embodiment, the thickness of the first electrode mixture portion of the first electrode plate or the second electrode mixture portion of the second electrode plate in the inclined region (e.g., belonging to the inclined region) is different from that in the normal region other than the inclined region (e.g., Figure 2 The thickness in the normal region B) can be reduced. The second strip 170 can be attached to the insert 156 of the extrusion device to correspond to the inclined region.

[0103] In one embodiment, the first strip attached to the electrode assembly and the second strip 170 attached to the insert paper of the extrusion device may comprise pressure-resistant or heat-resistant materials. For example, the extrusion device may comprise (e.g., may be) an HPC device capable of heating and extruding the pouch-type secondary battery 100 disposed on one side 156a of the insert paper. Therefore, the first and second strips 170, heated and extruded together, may be formed of suitable materials capable of withstanding high temperatures and pressures. For example, this material may be an insulating material that will not deform due to high pressure under the temperature and pressure of the pouch-type secondary battery formation process.

[0104] Figure 8 The positional relationship between the first and second strips according to an embodiment of the present disclosure is illustrated. Figure 9 The positional relationship between the first and second strips according to an embodiment of the present disclosure is illustrated.

[0105] Figure 8 and Figure 9 An example is shown where a pouch-type secondary battery 100, including an electrode assembly 110 with a first strip 130 attached, is placed on a pressing device including a paper insert with a second strip 170 attached, illustrating the overlap between the first strip 130 and the second strip 170. The redundant description above will not be repeated in the following text.

[0106] When the pouch-type secondary battery 100 is placed on insert paper and the lower boundary lines of the first strip 130 and the second strip 170 overlap each other in a straight line, stress concentration may occur in the first strip 130 and the second strip 170. In this case, lithium may linearly precipitate from the electrode plates during the heating and extrusion process. In some embodiments, when placed on insert paper, the position of the pouch-type secondary battery 100 may shift due to the thickness of the overlapping strips.

[0107] In one embodiment, such as Figure 8 As shown, the second zone 170 can cover the entire area of ​​the first zone 130.

[0108] More in detail, such as Figure 8As shown, the first strip 130 can be attached to the region in the electrode assembly 110 where the electrode mixture portion serving as the positive electrode plate and the electrode mixture portion serving as the negative electrode plate overlap. Typically, the negative electrode plate can be wide enough to cover the positive electrode plate, thereby preventing lithium from depositing in the battery; such deposits are defined as overhangs. In stacked electrode assemblies, tilted regions or severe separator lift may occur at the overlapping portions of the electrode mixture portions serving as the positive and negative electrode plates. On the other hand, in regions where the electrode mixture portions of the positive and negative electrode plates do not overlap, such as overhang regions, tilted regions or separator lift may occur relatively less frequently.

[0109] In the portion where the electrode mixture portion serving as the positive electrode plate and the electrode mixture portion serving as the negative electrode plate overlap, the first band 130 may be attached to the electrode assembly located in the inclined region (e.g., Figure 2 The corner portion at the inclined regions A and A'). For example, the first band 130 may be attached to a portion other than the overhang length (c). In some embodiments, the first band 130 may be attached to a portion including the overhang length (c).

[0110] In one embodiment, the second strip 170 may be attached to the insert of the extrusion device to cover the lower boundary of the first strip 130 at the position where the tab film serving as the electrode tab begins. For example, the second strip 170 may be attached to cover the length (a) between the end of the tab film and the end of the housing 140, the distance (b) between the end of the housing 140 and the electrode assembly 110, the overhang length (c), and the length (d) of the first strip 130. In other words, the length (e) of the second strip 170 may be greater than the length (a) between the end of the tab film and the end of the housing 140, the distance (b) between the end of the housing 140 and the electrode assembly 110, the overhang length (c), and the length (d) of the first strip 130. The second strip 170 may be attached to the position corresponding to the positive electrode plate to be longer than the first strip 130 by the length (f) between the end (or lower boundary) of the first strip 130 and the end (or lower boundary) of the second strip 170.

[0111] As another example, to suppress side reactions in the inclined region, the second band 170 may be attached to at least cover the overhang length (c) and the length (d) of the first band 130. As another example, the second band 170 may be attached to at least cover the length (d) of the first band 130.

[0112] In one embodiment, to avoid the lower boundaries of the first band 130 and the second band 170 overlapping each other in a straight line, the second band 70 can be arranged such that the end of the second band 170 is located on the upper side of the first band 130, as shown below. Figure 9 As shown.

[0113] In one embodiment, the second strip 170 may be attached to the insert of the extrusion device so as not to cover the lower boundary of the first strip 130 at the position where it serves as the beginning of the bonding film. For example, the second strip 170 may be attached to cover a portion of the length (b) between the end of the housing 140 and the electrode assembly 110, the overhang length (c), and the length (d) of the first strip 130. In this case, the second strip 170 may be attached to the position corresponding to the positive electrode plate so as to be shorter than the length (f) between the end (or lower boundary) of the first strip 130 and the end (or lower boundary) of the second strip 170.

[0114] Figure 10 A longitudinal cross-sectional view of an extrusion apparatus according to an embodiment of the present disclosure is shown.

[0115] In one embodiment, the pouch-type secondary battery 100 can be disposed on one side 156a of the insert 156 of the compression device, such that the lead terminals are exposed outside the insert 156. More specifically, as Figure 10 As shown, the lead wire tabs can be exposed in the upward direction of the insert 156. Therefore, pressure on the lead wire tabs and terminal portions can be prevented or substantially prevented.

[0116] In this case, the corner portion 138 and / or the inclined area of ​​the pouch-type secondary battery 100 (e.g., Figure 2 The inclined regions A and A' can be arranged at positions close to the upper part of the plate, such as 158 and 160. Figure 10 As shown. Therefore, the first strip 130 and the second strip 170 can be attached to the pouch-type secondary battery 100 and the insert paper 156 respectively by adjusting their positions, such that the corner portion 138 and / or inclined area of ​​the pouch-type secondary battery 100 are squeezed by the first plate 152 and the second plate 154. Reference Figure 10 The second strip 170 is illustrated as being attached to the opposite side 156b of the insert paper, which is opposite to the side 156a on which the pouch-type secondary battery 100 is placed, but this disclosure is not limited thereto, and the second strip 170 may be attached to the side 156a of the insert paper.

[0117] The capacity of a secondary battery may decrease as it continues to be charged and discharged. For example, the initial capacity might be 1000mAh, and it could decrease to 700, 600, or 500mAh after hundreds of charge / discharge cycles. Typically, the lifespan is defined as the number of charge / discharge cycles until the capacity decreases to 60% to 80% of its initial capacity. For example, in a lifespan of 500 cycles, this might mean 500 cycles at 100% DOD, where DOD refers to the depth of discharge.

[0118] In one embodiment, a pouch-type secondary battery manufactured using an HPC process by attaching the first and second strips together exhibits improved side reactions at the corner portions of the electrode assembly where the electrode terminals are located, even after 600 cycles. The pouch-type secondary battery manufactured using the HPC process by attaching the first and second strips together also exhibits improved flatness in flatness tests using HPC pressure-sensitive paper.

[0119] Figure 11 A flowchart illustrating a method for manufacturing a pouch-type secondary battery according to an embodiment of the present disclosure.

[0120] A method 180 for manufacturing a pouch-type secondary battery according to an embodiment of the present disclosure may include manufacturing an electrode assembly (S181), attaching a first strip to the electrode assembly (S182), assembling the pouch-type secondary battery (S183), and compressing the pouch-type secondary battery using a compression device to which the pouch-type secondary battery is attached (S184). For example, the electrode assembly may be manufactured by stacking a single unit cell (S181), the single unit cell including a first electrode plate having a first electrode terminal formed thereon, a second electrode plate having a second electrode terminal formed thereon, and a separator between the first electrode plate and the second electrode plate. The first strip may be attached to at least one side (e.g., at least one of a front side and a rear side) of the electrode assembly that is perpendicular or substantially perpendicular to the stacking direction (S182). The pouch-type secondary battery including the electrode assembly and the first strip may be assembled (S183), and the pouch-type secondary battery may be compressed using a compression device (S184).

[0121] In the step of assembling the pouch-type secondary battery including the electrode assembly and the first belt (S183), the housing containing the electrode assembly and the first belt can be sealed to assemble the pouch-type secondary battery.

[0122] In the step of squeezing the pouch-type secondary battery (S184), the squeezing device may include a first plate, a second plate opposite to the first plate, an insert having opposite ends connected to the upper portions of the first plate and the upper portions of the second plate respectively and located between the first plate and the second plate, and a second strip attached to the insert.

[0123] The second strip can be attached to the insert of the compression device to correspond to the corner portion of the pouch-type secondary battery, where the lead terminals of the pouch-type secondary battery are located.

[0124] However, the above Figure 11 The flowcharts are provided as examples of embodiments of this disclosure, and this disclosure is not limited thereto. For example, one or more processes may be added / changed / deleted, the order of one or more processes may be changed, and / or one or more processes may be executed simultaneously or substantially simultaneously with each other.

[0125] While this disclosure has been described above with reference to embodiments thereof, it is not limited thereto. Those skilled in the art will be able to make various modifications and variations within the spirit of this disclosure.

[0126] Description of some reference numerals

[0127] 100: Pouch-type secondary battery

[0128] 110: Electrode assembly

[0129] 112: Unitary Monomer

[0130] 114: First electrode plate

[0131] 114a: First electrode current collector plate

[0132] 114b: First electrode mixture portion

[0133] 116: First electrode connector

[0134] 118: Diaphragm

[0135] 120: Second electrode plate

[0136] 120a: Second electrode current collector plate

[0137] 120b: Second electrode mixture portion

[0138] 122: Second electrode connector

[0139] 124, 136: Second lead connector

[0140] 126, 134: First lead connector

[0141] 128: Enlarged view of the tilted area

[0142] 130, 132: First belt

[0143] 138: Corner section

[0144] 140: Casing

[0145] 142: Airbag

[0146] w1: Width

[0147] w2: width

[0148] A, A': Inclined regions

[0149] B: Normal area

[0150] a: Length between the end of the terminal block and the end of the housing; b: Length between the end of the housing and the electrode assembly.

[0151] c: Overhang length

[0152] d: Length of the first belt

[0153] e: Length of the second belt

[0154] f: Length between the end of the first belt and the end of the second belt; 150: Extrusion device.

[0155] 152: First board

[0156] 154: Second board

[0157] 156: Insert paper.

Claims

1. A pouch-type secondary battery, comprising: Electrode assembly, comprising a stack of unit cells, wherein the unit cell includes: First electrode plate; The first electrode terminal is located on the first electrode plate; Second electrode plate; The second electrode terminal piece is on the second electrode plate; and A diaphragm is located between the first electrode plate and the second electrode plate; and The first strip is attached to at least one side of the electrode assembly that is perpendicular to the stacking direction of the stack of the unit cell. The first strip is located at the corner of the electrode assembly, where the first electrode contact or the second electrode contact is located. The corner portion is located in the inclined region, which is where the thickness of the electrode assembly decreases.

2. The pouch-type secondary battery according to claim 1, wherein the inclined region is the portion of the first electrode mixture of the first electrode plate or the portion of the second electrode mixture of the second electrode plate where the thickness decreases.

3. The pouch-type secondary battery according to claim 2, wherein the thickness of the first electrode mixture portion of the first electrode plate or the second electrode mixture portion of the second electrode plate in the inclined region is less than the thickness in the region other than the inclined region.

4. The pouch-type secondary battery of claim 1, wherein the first strip is attached to a front side of the electrode assembly perpendicular to the stacking direction and a rear side of the electrode assembly opposite to the front side in the stacking direction.

5. The pouch-type secondary battery according to claim 1, wherein the first electrode terminal includes a stack of first electrode terminal groups, a first lead terminal is connected to the first electrode terminal group, the second electrode terminal includes a stack of second electrode terminal groups, and a second lead terminal is connected to the second electrode terminal group, and The first lead terminal and the second lead terminal are located in the same direction as each other in the electrode assembly.

6. The pouch-type secondary battery according to claim 1, wherein the first electrode terminal includes a stack of first electrode terminal groups, a first lead terminal is connected to the first electrode terminal group, the second electrode terminal includes a stack of second electrode terminal groups, and a second lead terminal is connected to the second electrode terminal group, and The first lead terminal and the second lead terminal are located in opposite directions to each other in the electrode assembly.

7. The pouch-type secondary battery according to claim 1, wherein the first strip comprises an insulating material.

8. A compression device for pouch-type secondary batteries, the compression device comprising: The first plate and the second plate opposite to the first plate; The insert has opposite ends that are respectively connected to the upper portions of the first plate and the upper portions of the second plate, and is located between the first plate and the second plate; as well as The second strip is attached to the insert paper. The second strip is attached to the corner portion of the pouch-shaped secondary battery placed on the insert paper, and the corner portion is where the lead terminals of the pouch-shaped secondary battery are located. The corner portion is located in the inclined region, which is where the thickness of the electrode assembly decreases.

9. The extrusion device according to claim 8, wherein the pouch-type secondary battery comprises: Electrode assembly, comprising a stack of unit cells, wherein the unit cell includes: First electrode plate; The first electrode terminal is located on the first electrode plate; Second electrode plate; The second electrode terminal piece is on the second electrode plate; and A diaphragm is located between the first electrode plate and the second electrode plate; and The first strip is attached to at least one side of the electrode assembly that is perpendicular to the stacking direction of the stack of the unit cell. The first strip is located at the corner portion of the electrode assembly, where the corner portion is the location of the first electrode contact piece or the second electrode contact piece.

10. The extrusion device according to claim 9, wherein the second belt covers the entire area of ​​the first belt.

11. The extrusion device according to claim 9, wherein one end of the second belt is located on the upper side of the first belt.

12. The extrusion device of claim 8, wherein the lead terminal is exposed outside the insert on which the pouch-type secondary battery is disposed.

13. The extrusion device according to claim 12, wherein the lead wire tab is exposed in the transverse direction of the inserted paper.

14. The extrusion device according to claim 12, wherein the lead wire tab is exposed in the upward direction of the inserted paper.

15. The pressurizing device according to claim 9, wherein the inclined region is a portion of the first electrode mixture of the first electrode plate or the portion of the second electrode mixture of the second electrode plate where the thickness decreases.

16. The pressurizing device of claim 15, wherein the thickness of the first electrode mixture portion of the first electrode plate or the second electrode mixture portion of the second electrode plate in the inclined region is less than the thickness in the region other than the inclined region.

17. The extrusion apparatus according to claim 9, wherein the first belt and the second belt comprise a pressure-resistant material or a heat-resistant material.

18. A method for manufacturing a pouch-type secondary battery, the method comprising: Electrode assemblies are manufactured by stacking unit cells, wherein the unit cells include: First electrode plate; The first electrode terminal is located on the first electrode plate; Second electrode plate; The second electrode terminal piece is on the second electrode plate; and A diaphragm is located between the first electrode plate and the second electrode plate; The first strip is attached to at least one side of the electrode assembly that is perpendicular to the stacking direction of the unit cell; The assembly includes the electrode assembly and the first strip of the pouch-type secondary battery; and The pouch-type secondary battery is compressed using a compression device. The extrusion device includes: The first plate and the second plate opposite to the first plate; A paper insert, having opposite ends respectively connected to the upper portions of the first plate and the upper portions of the second plate, and situated between the first plate and the second plate; and The second strip is attached to the insert paper. The first strip is located at the corner of the electrode assembly, where the first electrode contact or the second electrode contact is located. The corner portion is located in the inclined region, which is where the thickness of the electrode assembly decreases. The second strip is attached to the position corresponding to the first strip.

19. The method of claim 18, wherein the second band covers the entire area of ​​the first band.

20. The method of claim 18, wherein one end of the second band is on top of the first band.

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