Secondary battery, method for manufacturing the same, and pressure device used in the method

Abstract

An embodiment of the present invention relates to a method of manufacturing a secondary battery including an electrode assembly and a battery case provided to accommodate the electrode assembly and having a sealed edge, the method may include: a folding step of folding the edge; an attaching step of attaching an adhesive member to the folded edge; and a pressing step of pressing at least a partial region of an unattached region of the folded edge to which the adhesive member is not attached.

Description

Technical Field

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of priority from Korean Patent Application No. 10-2022-0127431, filed on October 5, 2022, and Korean Patent Application No. 10-2023-0060696, filed on May 10, 2023, which are hereby incorporated by reference in their entirety. Technical Field

[0004] The present invention relates to a secondary battery, a method for manufacturing the secondary battery, and a pressing device used in the method. Background Art

[0005] In order to solve the energy problem caused by environmental pollution and the depletion of petroleum resources, research and development of power generation based on environmentally friendly energy have been carried out. In particular, research on secondary batteries has been actively carried out, and various aspects such as materials, structures, processes and stability of secondary batteries have been studied.

[0006] Regarding the structure of the secondary battery, according to the shape of the battery case for accommodating the electrode assembly, the secondary battery can be classified into a pouch type, a prismatic type, a cylindrical type, etc. In the pouch type secondary battery, the sealing part or the degassing part formed on the edge occupies space, so for space efficiency, a double-sided folding DSF (Double Side Folding) process of folding the sealing part or the degassing part can be performed.

[0007] According to the related art, when the DSF process is performed, the tape is applied after the folding. Here, applying the tape to the entire surface of the edge is disadvantageous in delaying the flame propagation of the lead portion. In addition, partially applying the tape to the edge may cause a thickness difference between an unapplied area where the tape is not applied and an area where the tape is partially applied, which may cause physical interference in subsequent processes. Summary of the invention

[0008] Technical issues

[0009] An object of the present invention for solving the above problems is to provide a secondary battery capable of minimizing the thickness difference between an unattached area where tape is not attached and an attached area where tape is attached, thereby preventing physical interference, a method for manufacturing the secondary battery, and a pressing device used in the method.

[0010] Technical Solution

[0011] The method for manufacturing a secondary battery according to an embodiment of the present invention can manufacture a secondary battery including an electrode assembly and a battery case configured to accommodate the electrode assembly and having a sealed edge. The method for manufacturing a secondary battery may include: a folding process of folding the edge; an attaching process of attaching an adhesive member to the folded edge; and a pressing process of pressing at least a portion of an unattached area of ​​the folded edge to which the adhesive member is not attached.

[0012] A pressing device according to an embodiment of the present invention can press a secondary battery including an electrode assembly and a battery case configured to accommodate the electrode assembly and having a sealed edge, wherein a partial area of ​​the edge is attached with an adhesive member. The pressing device may include: a main body, the main body is configured so that the distance from the edge changes; and a protrusion, the protrusion protruding from the main body toward the edge so as to press at least a portion of the remaining area except the partial area.

[0013] A secondary battery according to an embodiment of the present invention may include: an electrode assembly; a battery case, which is configured to accommodate the electrode assembly and has a folded edge; and an adhesive member, which is attached to a partial area of ​​the folded edge, wherein at least a portion of an unattached area of ​​the folded edge to which the adhesive member is not attached is pressed.

[0014] Beneficial Effects

[0015] According to the preferred embodiments of the present invention, the thickness difference between regions of the secondary battery can be minimized.

[0016] According to the preferred embodiments of the present invention, it is possible to prevent the edge of the secondary battery from protruding unnecessarily.

[0017] According to the preferred embodiments of the present invention, the occurrence of physical interference due to the thickness difference and protrusion between regions of the secondary battery can be minimized.

[0018] According to the preferred embodiments of the present invention, space efficiency can be improved when secondary batteries are stacked. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is an assembly diagram showing a secondary battery according to an embodiment of the present invention.

[0020] Figure 2 is a flowchart illustrating a method of manufacturing a secondary battery according to an embodiment of the present invention.

[0021] Figure 3 is a longitudinal sectional view showing a secondary battery according to an embodiment of the present invention when viewed in one direction.

[0022] Figure 4a is a plan view showing an unattached region of a secondary battery according to an embodiment of the present invention.

[0023] Figure 4b is a perspective view showing a non-attached area of ​​a secondary battery according to an embodiment of the present invention.

[0024] Figure 5 is a side view showing a state in which a non-attached area of ​​a secondary battery is pressed using a pressing device according to the first embodiment of the present invention when viewed in another direction.

[0025] Figure 6 1 is a plan view showing a pressing region in which a pressing device presses a secondary battery according to a first embodiment of the present invention.

[0026] Figure 7 is a side view showing a state in which a non-attached area of ​​a secondary battery is pressed using a pressing device according to a second embodiment of the present invention when viewed in another direction.

[0027] Figure 8 1 is a plan view showing a pressing region in which a pressing device presses a secondary battery according to a second embodiment of the present invention.

[0028] Fig. 9 is a side view showing a state in which a non-attached area of ​​a secondary battery is pressed using a pressing device according to a third embodiment of the present invention when viewed in another direction.

[0029] Fig.10 1 is a plan view showing a pressing region in which a pressing device presses a secondary battery according to a third embodiment of the present invention.

[0030] Fig.11 1 is a side view showing a state in which a non-attached area of ​​a secondary battery is pressed using a pressing device according to a fourth embodiment of the present invention when viewed in another direction.

[0031] Fig.12 1 is a plan view showing a pressing region in which a pressing device presses a secondary battery according to a fourth embodiment of the present invention. DETAILED DESCRIPTION

[0032] Hereinafter, the preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily implement the present invention. However, the present invention can be implemented in different forms and should not be construed as being limited to the embodiments described herein.

[0033] In order to clearly describe the present invention, parts that are irrelevant to the description or detailed description of related well-known technologies that may unnecessarily obscure the subject matter of the present invention will be excluded. Throughout the specification, like reference numerals refer to like elements.

[0034] Furthermore, the terms or words used in the specification and claims should not be restrictively interpreted as ordinary meanings or dictionary-based meanings, but should be interpreted as meanings and concepts consistent with the scope of the present invention based on the principle that the inventor can appropriately define the concepts of the terms to best describe and interpret his or her invention.

[0035] Figure 1 is an assembly diagram showing a secondary battery according to an embodiment of the present invention.

[0036] The secondary battery 1 may include an electrode assembly 2. Electrodes and separators may be alternately stacked to provide an electrode assembly 2. For example, an electrode assembly 2 may be provided by alternately stacking electrodes (e.g., positive and negative electrodes) with a separator interposed between the electrodes. The electrode assembly 2 may include an electrode tab, and the electrode tabs may be connected to the positive electrode and the negative electrode, respectively. The electrode assembly 2 may include an electrode lead. The electrode lead may be connected to the electrode tab and electrically connect the electrode to the outside. The electrode assembly 2 is not limited to those described above and may be described with general content in the relevant technical field.

[0037] The secondary battery 1 may include a battery case 3. The battery case 3 may contain therein an electrode assembly 2. For example, the battery case 3 may be a pouch-type battery case. The electrode assembly 2 may be contained in the battery case 3, and the edge of the battery case 3 may be sealed.

[0038] The battery case 3 may include a receiving portion 10. The receiving portion 10 may be a portion that receives and seats the electrode assembly 2 in the battery case 3. The receiving portion 10 may define a receiving space in which the electrode assembly 2 may be received.

[0039] The battery case 3 may include a cup portion 20. The cup portion 20 may be provided in a shape surrounding the accommodation portion 10. Since the cup portion 20 is provided, the accommodation portion 10 may be provided.

[0040] The battery case 3 may include a degassing portion 30. The degassing portion 30 may be provided at a side of the cup portion 20, and discharge gas generated in the cup portion 20 through a degassing hole.

[0041] The battery case 3 may include an edge 40. After performing the degassing process, a portion of the degassing portion 30 may be cut away from the battery case 3. Since a portion of the degassing portion 30 is cut away, the length of the degassing portion 30 may be reduced, and the volume of the secondary battery 1 may be reduced. The remaining portion of the degassing portion 30 after a portion of the degassing portion 30 is cut away may be the edge 40.

[0042] As described above, since a portion of the degassing portion 30 is cut off to reduce the length of the degassing portion 30, the volume of the secondary battery 1 can be reduced. However, when the edge 40 remains as it is, the space efficiency of the secondary battery 1 may be deteriorated. Therefore, the edge 40 may be preferably folded.

[0043] Hereinafter, an embodiment capable of folding edge 40 , attaching an adhesive member to folded edge 40 , and pressing at least a portion of an unattached region to which the adhesive member is not attached to stably improve space efficiency of secondary battery 1 will be described.

[0044] Figure 2 is a flowchart showing a method of manufacturing a secondary battery 1 according to an embodiment of the present invention. Figure 3 , Figure 4a and Figure 4b describe Figure 2 A method for manufacturing a secondary battery 1, Figure 3 shows a longitudinal sectional view of the secondary battery 1 when viewed in one direction, Figure 4a and Figure 4b There are shown a plan view and a perspective view of the non-attached region 300 of the secondary battery 1. The same or similar description as the above description may also be applied to the present embodiment.

[0045] The method of manufacturing the secondary battery 1 may include a folding process of folding the edge 40 according to S100 .

[0046] The edge 40 may be folded multiple times. For example, the edge 40 may be folded twice using a double-sided folding DSF (Double Side Folding) process. Specifically, the edge 40 may include a first folding portion 41 and a second folding portion 42. The first folding portion 41 is a portion folded at a position relatively closer to the end of the edge 40, and the second folding portion 42 is a portion folded at a position relatively closer to the cup portion 20. The edge 40 may be folded once based on the first folding portion 41, and then the edge 40 may be folded twice based on the second folding portion 42.

[0047] The method of manufacturing the secondary battery 1 may include an attaching process of attaching the adhesive member 100 to the folded edge 40 according to S200 .

[0048] The adhesive member 100 may be attached to the secondary battery 1 through an attaching process. For example, the adhesive member 100 may be attached to cover a portion of the edge 40 and a portion of the cup portion 20. The adhesive member 100 may be attached to the edge 40 such that the edge 40 is fixed in a state of being folded toward the cup portion 20.

[0049] The attaching process may include attaching a plurality of adhesive members 100 to the edge 40 at intervals from each other. For example, a plurality of adhesive members 100 may be provided, and the plurality of adhesive members 100 may be attached at intervals along the edge 40. As a specific example, three adhesive members 100 may be provided, and the three adhesive members 100 may be attached at intervals along the edge 40. However, the number of adhesive members 100 is not limited to the aforementioned example.

[0050] In the attaching process, an unattached area 300 may be formed. For example, when a plurality of adhesive members 100 are attached to the edge 40 spaced apart from each other, an unattached area 300 where no adhesive member 100 is attached may be formed between the plurality of adhesive members 100.

[0051] Reference Figure 4a , the unattached area 300 may be formed on a portion of the cup portion 20. For example, the unattached area 300 may be formed on the upper portion of the cup portion 20 of the secondary battery 1. Figure 4b , the unattached area 300 may be formed on a portion of the edge 40. For example, the unattached area 300 may be formed on a portion of the side of the edge 40.

[0052] The following description of the thickness t of the unattached area 300 may correspond to the description of the thickness of the edge 40 .

[0053] The thickness t of the unattached area 300 (or the edge 40 corresponding to the unattached area 300) before the pressing process of the unattached area 300 may be greater than the thickness of the attached area to which the adhesive member 100 is attached. The thickness t may be the thickness t of the edge 40 in a state where the edge 40 is folded multiple times. The thickness t of the edge 40 may be the thickness in the lateral direction. Hereinafter, the thickness may be the thickness t of the unattached area 300.

[0054] The attaching process may include attaching an adhesive member having a melting point higher than a temperature exceeding room temperature.

[0055] The method of manufacturing the secondary battery 1 may include a pressing process of pressing at least a partial area of ​​the unattached region 300 to which the adhesive member 100 is not attached to the edge 40 according to S300 .

[0056] The pressing process may include pressing a portion of the secondary battery 1 by using a pressing device 200. The pressing device 200 is movable relative to the secondary battery 1. The pressing device 200 may include a protruding portion (e.g., Figure 5 The protrusion 220 in the middle is formed so as to press at least a portion of the non-attached area 300 of the secondary battery 1.

[0057] The pressing process may include pressing a portion of the secondary battery 1 toward a direction in which a thickness t of the portion of the secondary battery 1 is reduced by using the pressing device 200. For example, the pressing device 200 may press the portion of the secondary battery 1 in a direction toward the cup portion 120. In other words, the pressing device 200 may press the unattached region 300 of the edge 40 of the secondary battery 1 from a side thereof.

[0058] The pressing process may include pressing at least a partial area of ​​the unattached area 300 formed between the plurality of adhesive members 100 by using the pressing device 200 .

[0059] The pressing process may include pressing the at least partial region spaced apart from the attachment region to which the adhesive member 100 is attached by using the pressing device 200 .

[0060] The pressing process may include pressing the at least part of the region at a temperature exceeding room temperature by using the pressing device 200 .

[0061] The thickness t of the unattached area 300 (or the edge 40 corresponding to the unattached area 300) after the pressing process may not be greater than the thickness of the attached area to which the adhesive member 100 is attached. For example, the thickness t of the unattached area 300 may correspond to the thickness of the attached area to which the adhesive member 100 is attached, or may be less than the thickness of the attached area to which the adhesive member 100 is attached, by performing pressing in a direction in which the thickness t decreases using the pressing device 200.

[0062] The corresponding thickness may include the same thickness, or even if not the same, the thickness of a portion protruding outward within a small range.

[0063] In other words, the unattached region 300 may not protrude outward from the attached region to which the adhesive member 100 is attached after the pressing process. Therefore, a partial region (eg, the unattached region 300) of the edge 40 of the secondary battery may be prevented from protruding unnecessarily.

[0064] Figure 5 1 is a side view showing a state in which the non-attachment area 300 of the secondary battery 1 is pressed using the pressing device 200 according to the first embodiment of the present invention when viewed in another direction. Figure 6 1 is a plan view showing a pressing region 400 in which the pressing device 200 presses the secondary battery 1 according to the first embodiment of the present invention. The same or similar descriptions as those described above may also be applied to this embodiment.

[0065] Reference Figure 5 and Figure 6In the plan view in FIG. 1 , the pressing device 200 may press the unattached area 300 on one side of the edge 40 in the lateral direction of the secondary battery 1 toward a direction in which the thickness t of the unattached area 300 decreases.

[0066] The pressing device 200 may press the secondary battery 1. The secondary battery 1 may include an electrode assembly 2 and a battery case 3 provided to accommodate the electrode assembly 2 and having a sealed edge. The adhesive member 100 may be attached to a partial area of ​​the edge 40.

[0067] The pressing device 200 may include a main body 210. For example, the main body 210 may be arranged to vary in distance from the edge 40. In other words, the main body 210 may be movable relative to the edge 40.

[0068] The pressing device 200 may include a protrusion 220. For example, the protrusion 220 may protrude from the body 210 toward the edge 40 so as to press at least a portion of the remaining area (or the unattached area 300) except for the partial area (or the attached area) to which the adhesive member 100 is attached. The protrusion 220 may protrude from the body 210 to form a predetermined pattern. For example, the predetermined pattern may be determined based on the pressed area (e.g., the pressed area 400) of the unattached area 300 pressed by the protrusion 220.

[0069] The pressing device 200 may be configured to be heated. For example, the protrusion 220 provided to press at least a portion of the unattached area 300 may be configured to be heated to a temperature at least higher than room temperature.

[0070] The protrusion 220 of the pressing device 200 may protrude to form a pattern that is configured to press at least the area disposed between the adhesive members 100 among the unattached areas 300. For example, the protrusion 220 may protrude to form a pattern such as Figure 5 The pattern shown allows pressing mainly the area disposed between the adhesive members 100 (or the pressing area 400 ) in the unattached area 300 of the edge 40 . Specifically, the protrusions 220 may protrude to form a pattern disposed to press the area between the adhesive members 100 .

[0071] The region between the adhesive members 100 (or the pressed region 400) may be a region where the thickness difference between the unattached region 300 and the attached region to which the adhesive member 100 is attached is the largest. In this case, when the protrusion 220 presses the region between the adhesive members 100, the thickness of the unattached region 300 having the largest thickness difference and the thickness of the attached region to which the adhesive member 100 is attached may be uniform.

[0072] In the pressing device 200, the pressing device 200 can press the pressing area 400 in a state where at least the protrusion 220 of the pressing device 200 is heated to a temperature exceeding room temperature. When the protrusion 220 performs pressing in a heated state, the thickness of the non-attached area 300 having the largest thickness difference and the thickness of the attached area to which the adhesive member 100 is attached can be more effectively uniformized.

[0073] As described above, not only the thickness of the unattached area 300 and the thickness of the attached area may be uniform, but even when the thickness t of the unattached area 300 is smaller than the thickness of the attached area to which the adhesive member 100 is attached, space efficiency may be improved.

[0074] In the secondary battery 1 pressed by the pressing device 200, a portion of the unattached area 300 may be heat-pressed. For example, at least a portion of the unattached area 300 of the edge 40 where the adhesive member 100 is not attached (e.g., an area between the adhesive members 100) may be heat-pressed by heating and pressing the protrusion 220 protruding to form a predetermined pattern.

[0075] Since the area disposed between the adhesive members 100 among the unattached areas 300 is heat-pressed by heating and pressing, the thickness of at least the area disposed between the adhesive members 100 among the unattached areas 300 of the folded edge 40 where the adhesive member 100 is not attached can correspond to the thickness of the attached area to which the adhesive member 100 is attached, or be less than the thickness of the attached area to which the adhesive member 100 is attached.

[0076] According to the foregoing description, the occurrence of physical interference due to the thickness difference between regions of the secondary battery 1 may be minimized, and space efficiency may be improved when the secondary batteries 1 are stacked.

[0077] Figure 7 1 is a side view showing a state in which the non-attachment region 300 a of the secondary battery 1 a is pressed using the pressing device 200 a according to the second embodiment of the present invention when viewed in another direction. Figure 8 2 is a plan view showing a pressing area 400a where a pressing device 200a presses a secondary battery 1a according to a second embodiment of the present invention. The same or similar descriptions as those described above may also be applied to this embodiment.

[0078] The protrusion 220a of the pressing device 200a may protrude to form a pattern, that is, the pattern is configured to press at least the unattached area 300a. For example, the protrusion 220a may protrude to form a pattern such as Figure 7The pattern shown in the figure makes the entire unattached area 300a of the edge 40a pressed. Specifically, the protrusion 220 can protrude to form a pattern corresponding to the shape of the unattached area 300a, so that the entire unattached area 300a is pressed. The pressing area 400a can be an area corresponding to the unattached area 300a. When the protrusion 220a presses the pressing area 400a, the thickness difference between the unattached area 300a and the attached area to which the adhesive member 100a is attached can be minimized.

[0079] The pressing device 200a can press the pressing area 400a when at least the protrusion 220a is heated. When the protrusion 220a performs pressing in a heated state, the thickness difference between the non-attached area 300a and the attached area to which the adhesive member 100a is attached can be more effectively reduced.

[0080] In the secondary battery 1a pressed by the pressing device 200a, the unattached area 300a may be heat-pressed. For example, the unattached area 300a of the edge 40a where the adhesive member 100a is not attached may be heat-pressed by heating and pressing the protrusion 220a protruding to form a predetermined pattern.

[0081] Since the unattached area 300a is heat-pressed by heating and pressing, the thickness of the unattached area 300a of the folded edge 40a where the adhesive member 100a is not attached can correspond to the thickness of the attached area where the adhesive member 100a is attached, or be less than the thickness of the attached area where the adhesive member 100a is attached.

[0082] According to the foregoing description, the occurrence of physical interference due to the thickness difference between regions of the secondary battery 1 a may be minimized, and space efficiency may be improved when the secondary batteries 1 a are stacked.

[0083] Fig. 9 1 is a side view showing a state in which the non-attachment region 300 b of the secondary battery 1 b is pressed using the pressing device 200 b according to the third embodiment of the present invention when viewed in another direction. Fig.10 2 is a plan view showing a pressing area 400b in which a pressing device 200b presses a secondary battery 1b according to a third embodiment of the present invention. The same or similar descriptions as those described above may also be applied to this embodiment.

[0084] As described above, the pressing process including pressing at least a partial area of ​​the unattached area 300 b spaced apart from the attached area to which the adhesive member 100 b is attached will be described.

[0085] The protrusion 220b of the pressing device 200b may protrude to form a pattern that is configured to press at least the non-attached area 300b and to press spaced apart from the attached area to which the adhesive member 100b is attached. Fig. 9 The pattern shown in the figure makes it possible to press a portion of the unattached area 300b of the edge 40b. Specifically, the protrusion 220b can protrude to form such a pattern, that is, the pattern is arranged so that a portion of the unattached area 300b is pressed, while the portion adjacent to the adhesive member 100b in the unattached area 300b is not pressed. The pressing area 400b can be an area included in the unattached area 300b. When the protrusion 220b presses the pressing area 400b, the thickness difference between the pressing area 400b of the unattached area 300b and the attached area to which the adhesive member 100b is attached can be minimized.

[0086] The pressing device 200b can press the pressing area 400b when at least the protrusion 220b is heated. When the protrusion 220b performs pressing in a heated state, the thickness difference between the pressing area 400b of the non-attached area 300b and the attached area to which the adhesive member 100b is attached can be more effectively reduced.

[0087] In the secondary battery 1b pressed by the pressing device 200b, the pressing area 400b of the unattached area 300b may be heat-pressed. For example, the unattached area 300b of the edge 40b where the adhesive member 100b is not attached may be heat-pressed, and the area corresponding to the pressing area 400b in the unattached area 300b may be heat-pressed by heating and pressing the protrusion 220b protruding to form a predetermined pattern.

[0088] Since the pressed area 400b is heat-pressed by heating and pressing, the thickness of the pressed area 400b of the folded edge 40b may correspond to or be smaller than the thickness of the attached area to which the adhesive member 100b is attached.

[0089] According to the foregoing description, the occurrence of physical interference due to the thickness difference between regions of the secondary battery 1 b may be minimized, and space efficiency may be improved when the secondary batteries 1 b are stacked.

[0090] Fig.11 1 is a side view showing a state in which the non-attachment region 300 c of the secondary battery 1 c is pressed using the pressing device 200 c according to the fourth embodiment of the present invention when viewed in another direction. Fig.124 is a plan view showing a pressing area 400c where a pressing device 200c presses a secondary battery 1c according to a fourth embodiment of the present invention. The same or similar descriptions as those described above can also be applied to this embodiment.

[0091] As described above, the pressing process including pressing at least a portion of the attached region to which the adhesive member 100 c is attached and the non-attached region 300 c will be described.

[0092] The protrusion 220c of the pressing device 200c may protrude to form a pattern that is configured to press at least a portion of the attached area to which the adhesive member 100c is attached and the non-attached area 300c. For example, the protrusion 220c may protrude to form a pattern such as Fig.11 The pattern shown in the figure makes it possible to press the entire unattached area 300b of the edge 40c, and also press the area adjacent to the unattached area 300c in the adhesive member 100c. Specifically, when viewed from the upper side, the protrusion 220c can protrude to form a pattern that is set to cover the partial area to which the adhesive member 100c is attached and the unattached area 300c. The pressing area 400c can be an area including the unattached area 300c. When the protrusion 220c presses the pressing area 400c, the thickness difference between the unattached area 300c and the attached area to which the adhesive member 100c is attached can be minimized.

[0093] The pressing device 200c can press the pressing area 400c when at least the protrusion 220c is heated. When the protrusion 220c performs pressing in a heated state, the thickness difference between the non-attached area 300c and the attached area to which the adhesive member 100c is attached can be more effectively reduced.

[0094] As described above, when the protrusion 220c of the pressing device 200c also presses a portion of the adhesive member 100c, the adhesive member 100c may be an adhesive member having a melting point higher than a temperature exceeding room temperature to prevent damage to the adhesive member 100c. In other words, the adhesive member 100c may be an adhesive member having a melting point higher than a temperature corresponding to the heated state of the protrusion 220c.

[0095] In the secondary battery 1c pressed by the pressing device 200c, the pressing area 400c may be heat-pressed. For example, the unattached area 300c of the edge 40c where the adhesive member 100c is not attached may be at least heat-pressed, and the area corresponding to the pressing area 400c may be heat-pressed by heating and pressing the protrusion 220c protruding to form a predetermined pattern.

[0096] Since the pressed area 400c is heat-pressed by heating and pressing, the thickness of the pressed area 400c of the folded edge 40c may correspond to or be smaller than the thickness of the attached area to which the adhesive member 100c is attached.

[0097] According to the foregoing description, the occurrence of physical interference due to the thickness difference between regions of the secondary battery 1 c may be minimized, and space efficiency may be improved when the secondary batteries 1 c are stacked.

[0098] Although the present invention has been described with reference to limited embodiments and drawings, the present invention is not limited thereto and can be implemented in various ways by a person skilled in the art within the technical concept of the present invention and the equivalent scope of the appended claims.

[0099] [Reference Symbols]

[0100] 1. 1a, 1b, 1c: Secondary battery

[0101] 2: Electrode assembly

[0102] 3: Battery housing

[0103] 10: Accommodation

[0104] 20: Cup Department

[0105] 30: Degassing section

[0106] 40: Edge

[0107] 41: First folding part

[0108] 42: Second folding part

[0109] 100, 100a, 100b, 100c: bonding member

[0110] 200, 200a, 200b, 200c: pressing device

[0111] 210, 210a, 210b, 210c: Main body

[0112] 220, 220a, 220b, 220c: protrusion

[0113] 300, 300a, 300b, 300c: unattached area

[0114] 400, 400a, 400b, 400c: pressing area.

Claims

1. A method for manufacturing a secondary battery, the secondary battery comprising an electrode assembly and a battery case configured to accommodate the electrode assembly and having a sealed edge, the method comprising: A folding step of folding the edge; an attaching step of attaching the adhesive member to the folded edge; as well as A pressing step of pressing at least a portion of a non-attached area of ​​the folded edge to which the adhesive member is not attached.

2. The method according to claim 1, wherein the attaching step comprises attaching a plurality of adhesive members to the folded edge at intervals from each other, and The pressing process includes pressing at least a portion of the unattached region formed between the plurality of adhesive members. 3 . The method according to claim 1 , wherein the pressing process includes pressing the at least partial region spaced apart from an attachment region to which the adhesive member is attached. The method according to claim 1 , wherein the pressing step comprises pressing the at least part of the region at a temperature exceeding room temperature. 5 . The method according to claim 1 , wherein the pressing process includes pressing at least a portion of the attached region to which the adhesive member is attached and the unattached region. The method according to claim 5 , wherein the pressing step comprises performing the pressing at a temperature exceeding room temperature. 7 . The method according to claim 6 , wherein the attaching step includes attaching the adhesive member having a melting point higher than the temperature exceeding room temperature.

8. A pressing device for pressing a secondary battery, the secondary battery comprising an electrode assembly and a battery housing configured to accommodate the electrode assembly and having a sealed edge, wherein a partial area of ​​the edge is attached with an adhesive member, the pressing device comprising: a main body, the main body being arranged so that the distance from the edge varies; as well as A protrusion protrudes from the main body toward the edge so as to press at least a portion of a remaining area except the partial area.

9. The pressing device according to claim 8, wherein the protrusion is arranged to be heated. 10 . The pressing device according to claim 8 , wherein the protrusion protrudes from the body to form a predetermined pattern.

11. A secondary battery comprising: Electrode assembly; a battery case configured to accommodate the electrode assembly and having a folded edge; as well as an adhesive member attached to a partial area of ​​the folded edge, At least a portion of the unattached area of ​​the folded edge to which the adhesive member is not attached is pressed. 12 . The secondary battery according to claim 11 , wherein a thickness of the unattached region of the folded edge to which the adhesive member is not attached corresponds to a thickness of the partial region to which the adhesive member is attached.

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