Secondary battery, crimping device for secondary battery, and crimping method using same

Abstract

The invention discloses a secondary battery, a crimping device for the secondary battery, and a crimping method using the same. A secondary battery according to various embodiments of the present disclosure may include: a battery can accommodating an electrode assembly; and a cover plate coupled to one side of the battery can, in which the cover plate is in contact with and electrically connected to the battery can. Therefore, the sealing performance of the secondary battery can be improved.

Description

Technical Field

[0001] This disclosure relates to a secondary battery, a crimping device for the secondary battery, and a crimping method using the same. Background Technology

[0002] Secondary batteries are used as an energy source in electric vehicles or electronic devices. Secondary batteries employ jelly-roll-shaped electrode assemblies, which are formed by winding the negative electrode plate, positive electrode plate, and separator together, or electrode assemblies made by stacking the negative electrode plate, positive electrode plate, and separator in a suitable order.

[0003] This electrode assembly is housed in a housing and connected to the negative and positive terminals, with the housing sealed while the interior is filled with electrolyte. Summary of the Invention

[0004] Technical issues

[0005] According to one aspect of this disclosure, a secondary battery capable of improving sealing performance can be provided.

[0006] According to one aspect of this disclosure, a secondary battery capable of diversifying current movement paths can be provided.

[0007] Technical solution

[0008] The secondary battery according to various embodiments of the present disclosure may include: a battery canister housing an electrode assembly; and a cover plate attached to one side of the battery canister, wherein the cover plate contacts and is electrically connected to the battery canister.

[0009] In an exemplary embodiment, a first electrode terminal may be included, positioned relative to the electrode assembly and in the opposite direction to the opening of the battery can, and the cover may form a second electrode terminal having a polarity different from that of the first electrode terminal.

[0010] In an exemplary embodiment, the battery can may include a crimped portion of at least a section of the sidewall bent to cover at least a section of the cover plate.

[0011] In an exemplary embodiment, the cover may include: a main body portion configured to cover an open portion of the battery can; and an edge portion that protrudes upward around the circumference of the main body portion and contacts the battery can.

[0012] In an exemplary embodiment, the crimping portion may be configured to cover at least a portion of the edge portion.

[0013] In an exemplary embodiment, the edge portion may be bent at least once.

[0014] In an exemplary embodiment, the edge portion may include a first edge portion protruding upward from the main body portion and a second edge portion that curves in the first edge portion and is at least partially covered by the crimp portion.

[0015] In an exemplary embodiment, the crimping portion may include: a first horizontal portion that contacts the upper surface of the second edge portion; a vertical portion that extends downward from the first horizontal portion; and a second horizontal portion that bends from the vertical portion toward the sidewall of the battery can and contacts the lower surface of the first edge portion.

[0016] In an exemplary embodiment, the second horizontal portion may contact the inner side surface of the first edge portion.

[0017] In an exemplary embodiment, a sealing gasket may be included between the body portion and the crimping portion.

[0018] In an exemplary embodiment, the sealing gasket may contact the second horizontal portion of the crimping portion.

[0019] In an exemplary embodiment, the sealing gasket may be configured around the inner side of the edge portion.

[0020] In an exemplary embodiment, the sealing gasket may be annular.

[0021] In an exemplary embodiment, the sealing gasket can be pressed by the crimping portion.

[0022] The crimping apparatus according to various embodiments of the present disclosure may include: a die support device; and a crimping die, which descends through the die support device and applies pressing force to the opening of the battery can, wherein the crimping die presses the battery can to bend at least a portion of the sidewall of the battery can and a cover plate disposed in the opening of the battery can.

[0023] In an exemplary embodiment, the crimping mold may include: a first mold for preforming by pressing an open end of the sidewall of the battery can; and a second mold for forming a crimped portion by pressing the preformed sidewall of the battery can.

[0024] In an exemplary embodiment, a third mold may be included that presses the crimping portion to compress a sealing gasket disposed on the upper part of the cover plate.

[0025] In an exemplary embodiment, a preformed portion having an upwardly concave curved surface in a vertical cross section may be formed on the lower surface of the first mold, at least a portion of the curved surface including a direction conversion portion for guiding the open end of the sidewall of the battery can to bend downward.

[0026] In an exemplary embodiment, the preform may have a semi-circular shape in the vertical cross-section.

[0027] A crimping method for a secondary battery according to various embodiments of the present disclosure may include: a preparation step of sequentially placing a cover plate and a sealing gasket on one side of a battery can; a first crimping step of preforming a side wall of the battery can and at least a portion of the cover plate together; a second crimping step of forming a crimping portion such that the preformed side wall of the battery can covers and joins the bent portion of the cover plate, such that the sealing gasket is disposed between the unbent portion of the cover plate and the crimping portion; and a third crimping step of pressing the crimping portion such that the sealing gasket is squeezed by the crimping portion.

[0028] Technical effect

[0029] According to various embodiments of this disclosure, a secondary battery can be electrically connected by contacting a cover plate with a battery canister, without requiring a separate attachment process to configure the negative terminal.

[0030] In addition, the cover plate can have a relatively wider area than when attaching individual terminals, thereby diversifying the current flow path.

[0031] In addition, not only the battery canister, but the cover can also function as the negative terminal, thus increasing the freedom of cell configuration when forming battery packs or directly placing cells in vehicles.

[0032] Furthermore, in this disclosure, the edge of the cover plate, which bends together with the sidewall, is airtightly joined to the crimping part on the inside of the crimping part by means of a hook shape, thereby ensuring excellent sealing performance without welding.

[0033] Furthermore, in this disclosure, the sealing gasket disposed on the upper part of the cover plate is pressed by the crimping portion, thereby further improving the sealing performance. Attached Figure Description

[0034] Figure 1 This is a schematic cross-sectional view of a cylindrical secondary battery according to an exemplary embodiment of the present disclosure;

[0035] Figure 2 This is a partial cross-sectional view showing the initial configuration structure of the open portion of the battery can according to an exemplary embodiment of the present disclosure;

[0036] Figures 3 to 5 This is a reference illustrative of a sealing method using a crimping apparatus according to various embodiments of the present disclosure;

[0037] Figure 6 This is a flowchart of a crimping method according to various embodiments of the present disclosure. Detailed Implementation

[0038] The embodiments disclosed herein are provided to illustrate the present disclosure more fully to those skilled in the art. The following embodiments may be modified in various other ways, and the scope of the present disclosure is not limited to the following embodiments.

[0039] Hereinafter, for ease of explanation, some embodiments of the present disclosure will be described with reference to exemplary accompanying drawings. In labeling components in the various drawings, the same reference numerals will be used as much as possible for the same components, even if they are shown in different drawings.

[0040] The terms or words used in this specification and claims should not be limited to their ordinary or dictionary meanings, but should be interpreted as meanings and concepts consistent with the technical ideas of this disclosure, in accordance with the principle that the inventor can appropriately define the concepts of the terms in order to explain his invention in the best way.

[0041] The terminology used in this specification is for describing particular embodiments and is not intended to limit this disclosure. As used herein, the singular form may include the plural form unless the context clearly indicates otherwise.

[0042] Furthermore, when used to describe and claim the contents of this disclosure, expressions such as “comprise,” “consist of,” and “have” should be interpreted in a non-exclusive manner. Unless otherwise stated to the contrary, they indicate that the corresponding component may exist and should therefore be interpreted as potentially including other components rather than excluding them.

[0043] Furthermore, when describing the components of embodiments of this disclosure, terms such as first, second, A, B, (a), and (b) may be used. These terms are only used to distinguish the component from other components, and the nature, order, or sequence of the components are not limited by these terms.

[0044] It should be understood that when a component is described as being "connected" or "combined" to another component, the component can be directly connected or combined to the other component, but the component and the other component can also be "connected" or "combined" to yet another component.

[0045] The spatially related terms such as “beneath,” “below,” “lower,” “above,” and “upper” are used to readily understand an element or feature shown in the accompanying drawings in relation to another element or feature. Depending on the various states of manufacture or use of this disclosure, these spatially related terms are used to readily understand this disclosure and are not intended to limit it. For example, when an element or feature in the drawings is flipped, an element or feature described as “beneath” or “lower” becomes “above” or “upper.” Therefore, “beneath” is a concept that includes “above” or “lower.”

[0046] The embodiments described in this specification and the structures shown in the accompanying drawings are merely the most preferred embodiments of this disclosure and do not fully represent the technical concept of this disclosure. Therefore, it should be understood that various equivalents and variations may exist at the time of filing this application. Furthermore, detailed descriptions of well-known functions and structures that may unnecessarily obscure the spirit of this disclosure have been omitted.

[0047] Hereinafter, the cylindrical secondary battery 1 according to various embodiments of the present disclosure will be described in detail with reference to the accompanying drawings.

[0048] The secondary battery 1 described in this disclosure can be any type of conventional battery capable of converting the chemical energy of the material stored in the battery into electrical energy and capable of being charged / discharged multiple times.

[0049] In describing the various embodiments of this disclosure, the axial direction may refer to the central axis around which the jelly roll-shaped electrode assembly 10 is wound, or the direction in which the central axis of the battery can 100 formed on the coaxial axis extends, and the radial direction may refer to the direction closer to or farther from the aforementioned central axis.

[0050] Figure 1 This is a schematic cross-sectional view of a cylindrical secondary battery 1 according to an exemplary embodiment of the present disclosure.

[0051] See Figure 1 The secondary battery 1 according to an exemplary embodiment of the present disclosure may include an electrode assembly 10, a battery canister 100, a cover plate 200, a sealing gasket 300, and an upper current collector 400.

[0052] In addition, the secondary battery 1 may also include electrode terminals 600, terminal gaskets 700, insulators 800 and lower current collectors 500.

[0053] First, the electrode assembly 10 may include a first electrode plate (not shown), a second electrode plate (not shown), and a diaphragm (not shown).

[0054] The first electrode plate can be either a positive electrode plate or a negative electrode plate. Exemplarily, the first electrode plate can be a negative electrode plate. In an exemplary embodiment, the first electrode plate may include a negative electrode current collector in the form of a metal foil and a negative electrode coating on which a negative electrode active material is coated. For example, the negative electrode current collector may contain copper or nickel.

[0055] In an exemplary embodiment, the negative electrode coating may be a conductive coating and may contain a negative electrode active material. For example, the negative electrode active material may include silicon materials (e.g., metallic silicon and silicon dioxide), carbon-based materials (e.g., graphite materials, graphene-containing materials, hard carbon, soft carbon, carbon nanotubes, porous carbon, conductive carbon), tin-based materials, or metal oxides, but is not limited thereto; any negative electrode active material known to those skilled in the art may be used.

[0056] In an exemplary embodiment, the first electrode plate may include a first electrode coated portion on which a negative electrode coating is formed and a first electrode uncoated portion 11 on which no negative electrode coating is formed.

[0057] The second electrode plate can be either a positive or a negative electrode plate. When the second electrode plate is a positive electrode plate, the first electrode plate can be a negative electrode plate, and when the second electrode plate is a negative electrode plate, the first electrode plate can be a positive electrode plate.

[0058] Exemplarily, the second electrode plate may be a positive electrode plate. In an exemplary embodiment, the second electrode plate may include a positive current collector in the form of a metal foil and a positive electrode coating on which a positive electrode active material is coated. For example, the positive current collector may contain aluminum.

[0059] In an exemplary embodiment, the positive electrode coating may be a conductive coating and may contain a positive electrode active material. For example, the positive electrode active material may include lithium nickel manganese cobalt oxide (NMC), lithium manganese oxide (LMO), lithium iron phosphate (LFP), lithium cobalt oxide (LCO), lithium titanate (LTO), or chalcogenides (LiTiS2), but is not limited thereto; any positive electrode active material known to those skilled in the art may be used.

[0060] In an exemplary embodiment, the second electrode plate may include a second electrode coated portion on which a positive electrode coating is formed on the positive electrode current collector and a second electrode uncoated portion 12 on which no positive electrode active material is coated.

[0061] A diaphragm can be inserted between the first electrode plate and the second electrode plate to prevent a short circuit caused by electrical connection between the first electrode plate and the second electrode plate. Exemplarily, the diaphragm can comprise an electrically insulating material. For example, the diaphragm can comprise a polymeric material. For example, the diaphragm can comprise polyethylene, polypropylene, or combinations thereof, but is not limited thereto.

[0062] The electrode assembly 10 can be formed by stacking and winding the first electrode plate, diaphragm, and second electrode plate into a jelly roll shape. In an exemplary embodiment, the uncoated portion 11 of the first electrode and the uncoated portion 12 of the second electrode can be exposed at both ends in the axial direction of the electrode assembly 10 to define electrode tabs.

[0063] In this disclosure, the uncoated portions of the first and second electrode plates can be used as a tabless structure for electrode tabs without separate electrode tabs, but it is not limited to this. It is also obvious that a structure in which separate electrode tabs are connected from the first and second electrode plates can also be applied.

[0064] The battery can 100 may have an opening at at least one end to accommodate the electrode assembly 10. The interior of the battery can 100 has an internal space for accommodating the electrode assembly 10. For example, such as... Figure 2 It is described as having an open top for the battery canister 100, but it could also be the other way around, which is obvious.

[0065] The battery canister 100 may contain a conductive metallic material. The battery canister 100 may be electrically connected to either the first electrode plate or the second electrode plate.

[0066] The shape of the battery canister 100 can be determined to correspond to the specific shape of the electrode assembly 10. For example, the battery canister 100 can be cylindrical or cuboid.

[0067] The battery can 100 may include an opening formed at its upper axial direction, a lower wall 120 formed on the side opposite to the opening in the axial direction, and a side wall 110 connecting the opening and the lower wall 120. In an exemplary embodiment, electrode terminals 600 may be disposed on the lower wall 120 of the battery can 100.

[0068] First, the structure of the secondary battery 1 at the lower part of the electrode assembly 10 will be explained.

[0069] Electrode terminals 600 can be configured through terminal holes in the lower wall 120 of the battery canister 100. Electrode terminals 600 can be electrically connected to the lower current collector 500. Electrode terminals 600 can be electrically connected to the lower current collector 500 and serve as electrode terminals 600 of the secondary battery 1 of this disclosure. The electrode terminals 600 configured in the lower wall 120 of the battery canister 100 can be described as first electrode terminals. For example, electrode terminal 600 or the first electrode terminal can be a positive terminal.

[0070] In an exemplary embodiment, such as Figure 1 As shown, the electrode terminal 600 can be configured as a rivet. For example, the electrode terminal 600 can be fixed by passing through a terminal hole formed in the lower wall 120 of the battery canister 100.

[0071] The electrode terminal 600 can be electrically connected to the first electrode plate or the second electrode plate of the electrode assembly 10. For example, the electrode terminal 600 can be directly connected to the second electrode plate, or it can be connected to the second electrode plate through the lower current collector 500.

[0072] The electrode terminal 600 can be configured to be electrically insulated from the lower wall 120 of the battery canister 100. The electrode terminal 600 and the battery canister 100 can have different polarities.

[0073] The upper end of the electrode terminal 600 can be connected to the lower current collector 500 through the hollow of the insulator 800. The upper end of the electrode terminal 600 can be exposed to the outside of the battery can 100 and fixed in a state of insulation from the lower wall 120 of the battery can 100 by the terminal gasket 700.

[0074] Figure 2 The electrode terminal 600 is shown in an exemplary configuration as a rivet, but is not limited thereto, and any known configuration of electrode terminal 600 may obviously also be applied.

[0075] A terminal gasket 700 can be inserted between the electrode terminal 600 and the battery canister 100. The terminal gasket 700 prevents the electrode terminal 600 from directly contacting the battery canister 100. For example, the terminal gasket 700 can be made of an insulating material. The terminal gasket 700 can electrically insulate the electrode terminal 600 from the battery canister 100.

[0076] For example, the terminal gasket 700 may contain an elastic material. Exemplarily, when the electrode terminal 600 is riveted into the terminal hole, the terminal gasket 700 may be deformed under force. In this case, an elastic force may be formed on the terminal gasket 700, and the terminal gasket 700 may be inserted and fixed between the electrode terminal 600 and the battery canister 100.

[0077] In addition, the terminal gasket 700 can maintain airtightness with the electrode terminal 600 installed in the terminal hole of the lower wall 120 of the battery can 100.

[0078] The lower current collector 500 can be configured adjacent to the upper end of the electrode assembly 10 inside the battery canister 100. For example, the lower current collector 500 can be configured adjacent to the uncoated portion 12 of the second electrode of the second electrode plate. The lower current collector 500 can be electrically connected to the second electrode plate to provide a migration path for electrons. In an exemplary embodiment, the lower current collector 500 can be a positive current collector.

[0079] The lower current collector 500 can be electrically connected to the electrode terminal 600. The lower current collector 500 can be electrically connected to the upper end of the electrode terminal 600 and the second electrode plate of the electrode assembly 10 to provide an electron migration path.

[0080] For example, the lower current collector 500 can be in direct contact with the lower end of the electrode terminal 600 and the uncoated portion 12 of the second electrode. Alternatively, the lower current collector 500 can be electrically connected to the lower end of the electrode terminal 600 and the uncoated portion 12 of the second electrode via conductive components.

[0081] The lower current collector 500 can be configured to have a shape corresponding to the lower surface of the electrode assembly 10. For example, the lower current collector 500 can be a circular metal plate.

[0082] The lower current collector 500 can be configured to be electrically insulated from the battery canister 100, and the lower current collector 500 and the battery canister 100 can have different polarities. The lower current collector 500 can be electrically insulated from the side wall 110 and the outer wall of the battery canister 100 by an insulator 800.

[0083] The insulator 800 can be configured to be electrically insulated from the battery canister 100. The secondary battery 1 can be electrically insulated from the battery canister 100 by inserting the insulator 800 between the lower current collector 500 and the battery canister 100.

[0084] An insulator 800 may be disposed between the lower current collector 500 and the lower wall 120 of the battery canister 100 to prevent the lower current collector 500 from contacting the lower wall 120 or the side wall 110 of the battery canister 100.

[0085] Alternatively, when the lower current collector 500 is omitted and the electrode terminal 600 and the second electrode uncoated portion 12 are directly connected, the insulator 800 can be disposed between the second electrode uncoated portion 12 of the electrode assembly 10 and the lower wall 120 of the battery canister 100.

[0086] In an exemplary embodiment, the insulator 800 may be a hollow circular plate. Exemplarily, the electrode terminal 600 may penetrate the insulator 800 through its hollow structure and be electrically connected to the lower current collector 500.

[0087] Next, the structure of the secondary battery 1 on the upper part of the electrode assembly 10 will be described in detail.

[0088] In the manufacturing process of the secondary battery 1 disclosed herein, the electrolyte can be inserted together with the electrode assembly 10 through the opening of the battery canister 100. The electrolyte serves to enable lithium ions to migrate between the second electrode plate and the first electrode plate constituting the electrode assembly 10. Exemplarily, the electrolyte can be a non-aqueous organic electrolyte, which is a mixture of lithium salt and a high-purity organic solvent. Exemplarily, the electrolyte can also be a polymer or solid electrolyte utilizing a high molecular weight electrolyte.

[0089] Furthermore, in the manufacturing process of the secondary battery 1, a rolled edge 130 can be formed on the battery canister 100, such that after the electrode assembly 10 is housed inside, a portion of the side wall 110 of the battery canister is recessed towards the center. The battery canister 100 can provide physical fixing force to the electrode assembly 10 housed inside through the rolled edge 130. In another embodiment, the secondary battery can also be manufactured by fixing the electrode assembly 10 through the arrangement of internal components instead of forming the rolled edge 130 on the battery canister 100.

[0090] In addition, the opening of the battery can 100 is located at the top of the assembly, and the battery can 100 can be sealed by the cover plate 200 when configured with the upper current collector 400.

[0091] First, the upper current collector 400 can be disposed adjacent to the upper end of the electrode assembly 10 inside the battery can 100. For example, the upper current collector 400 can be disposed adjacent to the uncoated portion 11 of the first electrode of the first electrode plate inside the battery can 100.

[0092] The upper current collector 400 can be electrically connected to the first electrode plate to provide a migration path for electrons. The upper current collector 400 can be configured to correspond to the shape of the upper surface of the electrode assembly 10. For example, the upper current collector 400 can be a circular metal structure. For example, the upper current collector 400 can be a hollow circular plate shape.

[0093] In an exemplary embodiment, the upper current collector 400 may be a negative current collector. The upper current collector 400 may be electrically connected to the first electrode plate via the uncoated portion 11 of the first electrode. For example, the upper current collector 400 may be in direct contact with the uncoated portion 11 of the first electrode.

[0094] For example, the upper current collector 400 can be bonded to the uncoated portion 11 of the first electrode by extrusion, soldering, laser welding, etc., but is not limited to this. For example, the upper current collector 400 can be electrically connected to the uncoated portion 11 of the first electrode by a conductive component.

[0095] In an exemplary embodiment, the upper current collector 400 may be configured to be electrically connected to the battery canister 100, and the upper current collector 400 may have the same polarity as the battery canister 100. For example, the battery canister 100 may have a negative polarity and be used as a negative terminal.

[0096] For example, the upper current collector 400 may include an electrode connection portion 410 that is coupled to the uncoated portion 11 of the first electrode and a battery can connection portion 430 formed around the electrode connection portion 410 and connected to the battery can 100.

[0097] The battery can connecting part 430 can be placed in a portion of the side wall 110 of the battery can 100, which is recessed towards the center to form a beading part 130.

[0098] The cover plate 200 can be attached to the open part of the battery can 100 and serve to seal the open part of the battery can 100.

[0099] According to various embodiments of this disclosure, the cover plate 200 can be electrically connected to the battery can 100 and has the same polarity as the battery can 100. The cover plate 200 can be made of a conductive metal material. The cover plate 200 can be described as a second electrode terminal having a polarity different from the first electrode terminal described above. For example, the cover plate 200 or the second electrode terminal can directly contact the battery can 100 and function as a negative terminal together with the battery can 100.

[0100] Typically, in a structure that insulates the cover 200 from the battery canister 100, a separate negative terminal must be attached to the lower wall 120 or side wall 110 of the battery canister 100. However, when a negative terminal is attached to the lower wall 120 of the battery canister 100, a short circuit may occur due to its proximity to the positive terminal disposed on the lower wall 120. Furthermore, when a negative terminal is attached to the side wall 110 of the battery canister 100, the adhesion may be weakened due to the curvature of the side wall 110, thus the terminal may detach.

[0101] Conversely, in this disclosure, the negative terminal is configured by contacting the cover 200 with the battery canister 100 for electrical connection, eliminating the need for a separate attachment process. Furthermore, the cover 200 can have a relatively wider area than when attaching a separate terminal, thereby diversifying the current flow path. Moreover, not only the battery canister 100, but the cover 200 also functions as a negative terminal, thus increasing the flexibility in cell configuration when forming battery packs or directly mounting cells onto vehicles.

[0102] The cover plate 200 can be formed in a shape corresponding to the opening of the battery can 100. For example, the cover plate 200 can be generally circular. In an exemplary embodiment of this disclosure, the outer end of the cover plate 200 can be bent together with the side wall 110 of the opening of the battery can 100 to form a press-fit portion 150.

[0103] More specifically, the cover 200 may include a main body portion 210 configured to correspond to the shape of the opening portion of the battery can 100 and an edge portion 230 protruding upward around the periphery of the main body portion 210.

[0104] The main body 210 has a shape corresponding to the open portion of the battery can 100 and can be disposed on one side of the battery can. For example, the main body 210 can be disposed on the rolled edge portion 130 of the battery can 100. For example, the main body 210 can be disposed on the upper part of the upper current collector 400 with the battery can connecting portion 430 of the upper current collector 400 disposed on the rolled edge portion 130. The main body 210 can be configured to cover the open portion of the battery can 100.

[0105] In an exemplary embodiment, the main body 210 may include at least one terminal portion (not shown). The terminal portion may be configured to protrude laterally in an axial direction from one side of the main body 210. For example, the terminal portion may be coaxially disposed on the main body 210 with the central axis of the battery can, but is not limited thereto. The secondary battery of this disclosure can be easily contacted with external components (e.g., busbars, not shown) through the terminal portion, and provides a migration path for electrons.

[0106] In an exemplary embodiment, one side of the main body 210 may be configured with at least one notch (not shown) to facilitate breakage when the internal pressure of the battery can increases. For example, the notch may be configured as a groove formed at a predetermined depth on at least one of the upper or lower surfaces of the main body 210. For example, the notch may be formed on a terminal portion, but is not limited thereto.

[0107] The cover 200 can contact the side wall 110 of the battery can 100 via its edge 230. The edge 230 can contact the surface of the side wall 110 of the battery can 100. At least a portion of the upper end of the edge 230 can be bent together with the side wall 110 to form a press-fit portion 150. The edge 230 can be configured to cover a portion of the open end 111 of the side wall 110 that forms the open portion.

[0108] More specifically, the edge portion 230 may include a vertical edge portion 231 extending upward from the main body portion 210 and a horizontal edge portion 233 extending inward in a radial direction from the vertical edge portion 231. The vertical edge portion 231 may be described as a first edge portion, and the horizontal edge portion 233 as a second edge portion.

[0109] The horizontal edge portion 233 can be formed by bending the upper portion of the sidewall 110 inward during the pressing process of the crimping die 900 according to an exemplary embodiment of the present disclosure. For example, the edge portion 230 can be bent at least once.

[0110] The outer surface of the vertical edge portion 231 can contact the inner surface of the sidewall 110, and the inner surface of the vertical edge portion 231 can contact the second horizontal portion 155 of the sidewall 110. That is, the inner surface of the vertical edge portion 231 can contact the upper end surface of the sidewall 110.

[0111] The horizontal edge portion 233 can be covered by the side wall 110 of the battery canister 100. For example, the upper surface of the horizontal edge portion 233 can contact the first horizontal portion 151 of the side wall 110, the lower surface of the horizontal edge portion 233 can contact the second horizontal portion 155 of the side wall 110, and the end face of the horizontal edge portion 233 can contact the vertical portion 153 of the side wall 110.

[0112] Furthermore, at least a portion of the upper section of the sidewall 110 forming the open portion of the battery can 100 can be pressed and bent by the crimping mold 900 to form a crimped portion 150. The crimped portion 150 can be formed on the upper part of the rolled edge portion 130. The crimped portion 150 can be formed by bending together with the edge portion 230 while covering the edge portion 230 on the inside. In this disclosure, the specific process for forming the crimped portion 150 will be described later.

[0113] More specifically, the crimping portion 150 may include a first horizontal portion 151 that bends inward in a radial direction and extends toward the center of the electrode assembly 10, a vertical portion 153 that extends downward from the first horizontal portion 151 toward the electrode assembly 10, and a second horizontal portion 155 that extends from the vertical portion 153 toward the sidewall 110 of the battery can 100.

[0114] At least a portion of the edge portion 230 of the cover plate 200 is disposed inside the crimping portion 150, allowing the battery canister 100 to be sealed while the crimping portion 150 covers the edge portion 230. Specifically, the lower surface of the first horizontal portion 151 can contact the upper surface of the horizontal edge portion 233, and the upper surface of the second horizontal portion 155 can contact the lower surface of the horizontal edge portion 233. The inner surface of the vertical portion 153 can contact the end surface of the horizontal edge portion 233. Furthermore, the end surface of the second horizontal portion 155 can contact the inner surface of the vertical edge portion 231.

[0115] In this disclosure, the sealing performance of the can is improved without welding by pressing with the crimped portion 150 covering the edge portion 230.

[0116] Additionally, a sealing gasket 300 can be disposed between the crimping portion 150 and the cover plate 200 to further improve sealing performance. The sealing gasket 300, inserted between the cover plate 200 and the crimping portion 150 of the side wall 110, maintains airtightness. The sealing gasket 300 can be pressed down by the crimping portion.

[0117] In an exemplary embodiment, the sealing gasket 300 may be configured as an annular shape. The sealing gasket 300 may be configured as an annular shape having a predetermined thickness in the axial direction and an extended length in the radial direction. The sealing gasket 300 may be disposed on the main body 210 of the cover plate 200 around the inner side of the edge 230 of the cover plate 200. The sealing gasket 300 may be formed of an elastic material.

[0118] The sealing gasket 300 can be inserted between the second horizontal portion 155 of the crimping portion 150 and the main body portion 210 of the cover plate 200. The upper surface of the sealing gasket 300 can contact the second horizontal portion 155 of the crimping portion 150, and the lower surface of the sealing gasket 300 can contact the upper surface of the main body portion 210 of the cover plate 200. In addition, the outer side surface of the sealing gasket 300 can contact the inner side surface of the vertical edge portion 231.

[0119] That is, in this disclosure, the sealing gasket 300 may be a structure inserted between the outer side of the side wall 110 of the battery can 100 and the cover plate 200.

[0120] The sealing gasket 300 can be pressed by the crimping part 150 to maintain airtightness while its upper surface, lower surface and inner surface are in contact with the crimping part 150, the main body 210 and the edge part 230 of the cover plate 200, respectively.

[0121] In this disclosure, there is a structure in which the battery can 100 and the cover plate 200 are in direct contact, and the battery can 100 can be sealed without welding.

[0122] In the manufacturing process disclosed herein, since the secondary battery 1 has a structure in which the open end 111 of the sidewall 110 is bent together with the edge portion 230 of the cover plate 200 to cover the edge portion 230, the sealing performance of the battery can 100 can be ensured without welding when the edge portion 230 of the cover plate 200 is in contact with the sidewall 110. Furthermore, the sealing performance can be further improved by pressing the sealing gasket 300 against the main body portion 210 of the cover plate 200 through the bent crimp portion 150 of the sidewall 110.

[0123] Hereinafter, the crimping apparatus according to various embodiments of the present disclosure will be described in detail with reference to the accompanying drawings.

[0124] Figure 2 This is a partial cross-sectional view showing the initial configuration structure of the open portion of the battery can 100 according to an exemplary embodiment of the present disclosure.

[0125] See Figure 2 In the secondary battery 1 according to various embodiments of the present disclosure, an upper current collector 400, a cover plate 200 and a sealing gasket 300 may be sequentially arranged on the rolled edge portion 130 of the battery can 100 for a pressing process.

[0126] For example, the electrode assembly 10 can be housed inside the battery can 100 while the electrode connection portion 410 of the upper current collector 400 is welded to the first electrode plate of the electrode assembly 10, and the battery can connection portion 430 of the upper current collector 400 is placed on the rolled edge portion 130.

[0127] The cover plate 200 may include a main body portion 210 and an edge portion 230 protruding upward around the circumference of the main body portion 210, as described above. When the main body portion 210 of the cover plate 200 is placed on the upper collector plate 400, the edge portion 230 may contact the side wall 110 of the battery can 100. At this time, the upper end of the edge portion 230 may be configured to be lower than the open end 111 of the side wall 110 of the battery can 100.

[0128] In this disclosure, since the open end 111 of the sidewall 110 is configured to be higher than the upper end of the edge portion 230, when the pressing mold 900 descends, the sidewall 110 configured on the outer side can be pressed first, while the edge portion 230 configured on the inner side is pressed by the sidewall 110.

[0129] An annular sealing gasket 300 can be disposed on the upper part of the cover plate 200. At this time, the sealing gasket 300 can be disposed around the inner side of the edge portion 230, and the outer side of the sealing gasket 300 can be configured to contact the inner side of the edge portion 230.

[0130] As described above, when the cover plate 200 and the sealing gasket 300 are arranged in the open part of the battery can 100, a pressing process can then be performed.

[0131] The crimping process can be performed using a crimping device according to various embodiments of the present disclosure. The crimping device is a means of sealing the battery canister 100 of the secondary battery 1 by pressing and bending the upper end of the secondary battery 1 after the preparation steps have been completed.

[0132] The crimping device may include a crimping die 900 and a die support device (not shown) for supporting the crimping die 900 so that it descends from above to below the battery can 100.

[0133] The crimping mold 900 according to various embodiments of the present disclosure may include: a first mold 900a, which, by pressing, gradually tilts the open end 111 of the side wall 110 of the battery can 100 toward the central axis of the battery can 100, thereby making the side wall 110 approach the shape of covering the edge portion 230; and a second mold 900b, which, by pressing, forms a first horizontal portion 151, a vertical portion 153, and a second horizontal portion 155 on the side wall 110, thereby making the side wall 110 in the shape of covering the edge portion 230. Furthermore, the crimping mold 900 may also include a third mold 900c, which, by pressing, causes the crimping portion 150 to press against the sealing gasket 300.

[0134] The first to third molds 900c of the crimping device can be configured to descend while rotating about the central axis of the battery can 100 via the mold support device.

[0135] Figures 3 to 5 This is a reference figure used to illustrate a sealing method using a crimping device according to various embodiments of the present disclosure.

[0136] See Figure 3 With the first mold 900a aligned with the central axis of the battery can 100, the first mold 900a can descend from the top of the battery can 100 downwards.

[0137] At this time, the lower surface of the first mold 900a opposite to the open portion of the battery canister 100 may include a preformed portion 910 formed as a curved surface with an upward concave shape in a vertical cross section. The process of forming using the preformed portion 910 of the first mold 900a can be described as a preforming process.

[0138] For example, the preform 910 may be formed in a semi-circular shape in a vertical cross section. The preform 910 may include an entry portion 911 formed on the outermost side of the semi-circular shape, a direction conversion portion 913 formed on the uppermost side of the semi-circular shape, and a tail portion 915 formed on the innermost side of the semi-circular shape.

[0139] When the first mold 900a presses the open portion of the battery can 100 from top to bottom, the open end 111 of the side wall 110 can gradually tilt towards the central axis of the battery can 100 along the curved surface of the preformed portion 910.

[0140] First, the open end 111 of the side wall 110 contacts the entry part 911 of the preformed part 910 and begins to tilt along the curved surface, gradually tilting towards the central axis of the battery can 100 until the direction conversion part 913.

[0141] Subsequently, as the first mold 900a continues to descend, the open end 111 of the sidewall 110 can be gradually guided by the direction conversion part 913 to bend toward the electrode assembly 10.

[0142] For example, the open end 111 of the sidewall 110 may pass through the tail section 915 and at least a portion of the section may be bent in a direction away from the central axis of the battery can 100.

[0143] Furthermore, the edge portion 230 of the cover plate 200 can be bent together with the open end 111 of the side wall 110 as it is pressed and bent by the first mold 900a. At least a portion of the upper end of the edge portion 230 can be pressed together with the open end 111 of the side wall 110 and tilted. At this time, a state can be formed in which the upper end portion of the edge portion 230 is covered by the open end 111 of the side wall 110 while tilting inward.

[0144] By applying pressure as the first mold 900a descends, the open end 111 of the sidewall 110 is bent along the inlet 911, the direction conversion part 913, and the tail part 915, thereby forming a state adjacent to the sealing gasket 300. The process of pressing through the pre-forming part 910 of the first mold 900a can be described as the first pressing step.

[0145] See Figure 4 After the first pressing step is completed, in the second pressing step, pressure can be applied to the battery can 100 by the second mold 900b. With the second mold 900b aligned with the central axis of the battery can 100, the second mold 900b can be lowered from the top of the battery can 100.

[0146] At this time, the lower surface of the second mold 900b opposite to the open portion of the battery can 100 may include a main forming portion 920 that is recessed upward in the vertical cross section.

[0147] For example, the main forming portion 920 may include a first vertical forming portion 921 that contacts the sidewall 110 in a vertical cross-section, a first horizontal forming portion 923 for forming a first horizontal portion 151 of the press-fit portion 150, and a second vertical forming portion 925 for forming a vertical portion 153 of the press-fit portion 150. Furthermore, in a vertical cross-section, the end of the second vertical forming portion 925 may also include a stepped portion 927 for preventing interference with the sealing gasket 300.

[0148] When the second mold 900b descends to provide pressing pressure on the pre-formed sidewall 110, the pre-formed sidewall 110 can be pressed and formed according to the shape of the main forming part 920 of the second mold 900b, so that the sidewall 110 is in the form of covering the edge part 230.

[0149] In the second crimping step, a horizontal edge portion 233 may be formed, in which the upper end portion of the edge portion 230 bends toward the central axis of the battery can 100. The horizontal edge portion 233 may be formed by bending the upper end portion of the edge portion 230 into a hook shape.

[0150] Furthermore, the sidewall 110 forms a first horizontal portion 151 that contacts the upper surface of the horizontal edge portion 233, a vertical portion 153 that contacts the end surface of the horizontal edge portion 233, and a second horizontal portion 155 that contacts the lower surface of the horizontal edge portion 233, thereby forming a shape in which the sidewall 110 covers the horizontal edge portion 233.

[0151] In this disclosure, by tightly fitting the crimped portion 150 to the outside of the hook-shaped edge portion 230, the sealing performance of the battery can 100 can be improved compared with the existing crimped structure.

[0152] Additionally, the sealing gasket 300 can be disposed between the main body portion 210, which serves as the unbent section of the cover plate 200, and the crimping portion 150. For example, the second horizontal portion 155 of the crimping portion 150 can be disposed adjacent to the sealing gasket 300.

[0153] At this point, the second horizontal portion 155 of the crimping portion 150 may not be able to form a sufficiently tight fit with the sealing gasket 300. However, through the subsequent third crimping step, the crimping portion 150 fully compresses the sealing gasket 300, thereby improving the sealing performance. It should be noted that... Figure 4 For ease of understanding, the distance between the crimped part 150 and the sealing gasket 300 is slightly exaggerated.

[0154] See Figure 5 In the third pressing step, pressure can be applied to the battery can 100 using the third mold 900c. With the third mold 900c aligned with the central axis of the battery can 100, the third mold 900c can be lowered from above the battery can 100.

[0155] The lower surface of the third mold 900c, opposite the open portion of the battery canister 100, may include a main molding portion 930 that is recessed upward in a vertical cross section. The shape of the main molding portion 930 is the same as that of the main molding portion 920 of the second mold 900b, but the depth of the recess differs.

[0156] For example, the main forming portion 930 may include a first vertical forming portion 931 that contacts the sidewall 110 in a vertical cross-section, a first horizontal forming portion 933 for forming a first horizontal portion 151 of the press-fit portion 150, and a second vertical forming portion 935 for forming the vertical portion 153 of the press-fit portion 150. Furthermore, in a vertical cross-section, the end of the second vertical forming portion 935 may also include a stepped portion 937 for preventing interference with the sealing gasket 300.

[0157] For example, the recess depth of the first horizontal forming portion 933 of the main forming portion 930 of the third mold 900c can be formed to be shallower than the recess depth of the first horizontal forming portion 923 of the main forming portion 920 of the second mold 900b.

[0158] When pressure is applied to the battery canister 100 through the third mold 900c, the crimping portion 150 of the side wall 110 is pressed downward, thereby allowing it to fit tightly against the sealing gasket 300. During the process of the crimping portion 150 fitting tightly against the sealing gasket 300, the first horizontal portion 151, the vertical portion 153, and the second horizontal portion 155 of the crimping portion 150 can be airtightly combined with the horizontal edge portion 233.

[0159] In this disclosure, by bending the crimping portion 150 of the sidewall 110 to form a first horizontal portion 151, a vertical portion 153, and a second horizontal portion 155, a structure is formed that tightly covers the horizontal edge portion 233 that is bent together with the inner side, thereby ensuring sealing performance in the structure.

[0160] Furthermore, in this disclosure, the sealing performance can be further enhanced by pressing the sealing gasket 300 with the second horizontal portion 155 of the crimping portion 150. This can be achieved by ensuring the sealing performance through a structure in which the sealing gasket 300, disposed between the sidewall 110 of the battery can 100 and the main body portion 210 of the cover plate 200, is pressed against the outer side of the sidewall 110 of the battery can 100.

[0161] Figure 6 This is a flowchart of a crimping method according to various embodiments of the present disclosure.

[0162] The secondary battery 1 according to various embodiments of this disclosure can be sealed by the above-described crimping device.

[0163] First, in the preparation step, a cover plate 200 and a sealing gasket 300 can be installed on one side of the battery can 100 (S610). For example, in the preparation step, a cover plate 200 and a sealing gasket 300 can be installed on the rolled edge 130 of the battery can 100.

[0164] As the first mold 900a descends from the top of the battery can 100, pressure is applied to the open end 111 of the side wall 110 by the preforming part 910, causing the open end 111 of the side wall 110 to bend along the inlet 911, the direction conversion part 913 and the tailing part 915, thereby performing preforming for forming the crimping part 150 (S620).

[0165] The upper portion of the edge 230 is pressed by the sidewall 110 and begins to tilt inward. The sidewall 110 can cover the edge 230 and the upper end bends downward to approach the sealing gasket 300.

[0166] At this time, the side wall 110 tilts and presses the edge 230 of the cover plate 200 which is adjacent to the inner side of the side wall 110, and the side wall 110 and the edge 230 of the cover plate 200 can be bent together.

[0167] As the second mold 900b descends from the top to the bottom of the battery can 100, a crimping portion 150 including a first horizontal portion 151, a vertical portion 153, and a second horizontal portion 155 can be formed at the open end 111 of the side wall 110 (S630).

[0168] Specifically, a first horizontal portion 151 can be formed by applying downward pressure to the curved sidewall 110 using a first horizontal forming portion 923. At this time, the sidewall 110 can be prevented from deforming outwards by the first vertical forming portion 921, and a vertical portion 153 can be formed by a second vertical forming portion 925. The end of the sidewall 110 can be pressed between itself and the sealing gasket 300 by the downward pressure of the first horizontal forming portion 923, thereby forming a second horizontal portion 155. The open end 111 of the sidewall 110 can be joined to the horizontal edge portion 233 of the cover plate 200 to form a press-fit portion 150.

[0169] In this disclosure, the edge portion 230 of the cover plate 200, which bends together with the side wall 110, is airtightly joined to the crimping portion 150 on the inside of the crimping portion 150 by means of a hook shape, thereby ensuring excellent sealing performance without welding.

[0170] Subsequently, as the third mold 900c descends from the top of the battery can 100 downwards, it presses down on the pressing part 150, thereby squeezing the sealing gasket 300 disposed on the upper part of the cover plate 200 (S640).

[0171] In this disclosure, the sealing gasket 300 undergoes elastic deformation between the cover plate 200 and the pressing portion 150, thereby further improving the sealing performance of the battery can 100.

[0172] As described above, with respect to the secondary battery 1 according to various embodiments of the present disclosure, the cover plate 200 is in direct contact with the battery can 100, and therefore has the same polarity as the battery can 100 and can be used as an electrode terminal 600.

[0173] In this disclosure, the negative terminal can be configured without a separate attachment process by contacting and electrically connecting the cover plate 200 to the battery canister 100. Furthermore, the cover plate 200 can have a relatively wider area than when attaching a separate terminal, thereby diversifying the current flow path. Moreover, not only the battery canister 100, but the cover plate 200 can also function as a negative terminal, thus increasing the flexibility in cell configuration when forming battery packs or directly mounting cells onto vehicles.

[0174] In this disclosure, the edge portion 230 of the cover plate 200, which bends together with the side wall 110, is airtightly joined to the crimping portion 150 on the inside of the crimping portion 150 by means of a hook shape, thereby ensuring excellent sealing performance without welding.

[0175] Furthermore, in this disclosure, the sealing gasket 300 disposed on the upper part of the cover plate 200 is pressed by the crimping part 150, thereby further improving the sealing performance.

[0176] This disclosure is not necessarily limited to these embodiments because all the components described above that constitute the embodiments of this disclosure are combined into one or work in combination. That is, all components may also work selectively in more than one combination, provided they are within the scope of the purpose of this disclosure. Unless otherwise defined, all terms, including technical or scientific terms, shall have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains. Terms commonly used, such as those defined in dictionaries, shall be interpreted as having a meaning consistent with the meaning in the context of the relevant art and shall not be construed as having an ideal or overly formal meaning unless expressly defined in this disclosure.

[0177] The above description is merely illustrative of the technical concept of this disclosure. Those skilled in the art can make various modifications and variations without departing from the essential characteristics of this disclosure. Therefore, the embodiments disclosed herein are for illustrative purposes only and not for limiting the technical concept of this disclosure, and the scope of the technical concept of this disclosure is not limited by these embodiments. The scope of protection of this disclosure should be interpreted through the appended claims, and all technical concepts within the same scope should be interpreted as included within the scope of the rights of this disclosure.

Claims

1. A secondary battery, comprising: Battery canister, which houses the electrode assembly; as well as The cover plate is attached to one side of the battery canister. The cover plate is in contact with and electrically connected to the battery can.

2. The secondary battery according to claim 1, wherein, Includes a first electrode terminal configured with reference to the electrode assembly in the opposite direction to the opening of the battery can. The cover plate forms a second electrode terminal having a different polarity than the first electrode terminal.

3. The secondary battery according to claim 1, wherein, The battery can includes at least a portion of the sidewall bent into a crimped portion that covers at least a portion of the cover plate.

4. The secondary battery according to any one of claims 1 to 3, wherein, The cover plate includes: The main body is configured to cover the open portion of the battery canister; and The edge portion protrudes upward around the periphery of the main body portion and contacts the battery can.

5. The secondary battery according to claim 4, wherein, The edge bends at least once.

6. The secondary battery according to claim 4, wherein, The edge portion includes a first edge portion that protrudes upward from the main body portion and a second edge portion that curves in the first edge portion and is at least partially covered by the crimp portion.

7. The secondary battery according to claim 6, wherein, The crimping portion includes: The first horizontal portion contacts the upper surface of the second edge portion; A vertical portion extending downward from the first horizontal portion; and The second horizontal portion bends from the vertical portion toward the side wall of the battery can and contacts the lower surface of the first edge portion.

8. The secondary battery according to claim 7, wherein, The second horizontal portion contacts the inner side of the first edge portion.

9. The secondary battery according to claim 7, wherein, Includes a sealing gasket disposed between the main body and the crimping portion.

10. The secondary battery according to claim 9, wherein, The sealing gasket contacts the second horizontal portion of the crimping portion.

11. The secondary battery according to claim 9, wherein, The sealing gasket is disposed around the inner side of the edge portion.

12. A crimping device, comprising: Mold support device; as well as The pressing die descends via the die support device and applies pressing pressure to the opening of the battery can. The pressing mold presses the battery can to bend at least a portion of the sidewall of the battery can and the cover plate disposed in the opening of the battery can.

13. The crimping device according to claim 12, wherein, The pressing die includes: The first mold is pre-formed by pressing the open end of the side wall of the battery can; The second mold forms a pressing portion by pressing the side wall of the pre-formed battery can; and The third mold presses the pressing part to compress the sealing gasket disposed on the upper part of the cover plate.

14. The crimping device according to claim 13, wherein, A preform portion with an upwardly concave curved surface in a vertical cross-section is formed on the lower surface of the first mold. At least a portion of the curved surface includes a direction-changing section for guiding the open end of the sidewall of the battery can to bend downwards.

15. A crimping method, comprising: Preparation steps: Place the cover plate and sealing gasket on one side of the battery can in sequence; In the first pressing step, the pre-formed sidewall of the battery can and at least a portion of the cover plate are bent together; The second pressing step involves forming a pressing portion to cover and join the curved section of the cover plate with the side wall of the pre-formed battery can, such that the sealing gasket is disposed between the uncurved section of the cover plate and the pressing portion. as well as The third pressing step involves pressing the pressing part to squeeze the sealing gasket.

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