Secondary battery

Abstract

The secondary battery includes an electrode assembly including a first electrode having a first electrode tab coupled to an insulating tape, a separator, and a second electrode, a case having one open side and accommodating the electrode assembly, the case being electrically connected to the second electrode, a cap assembly sealing the one open side of the case, the cap assembly being electrically connected to the first electrode tab, an insulating sheet disposed between the cap assembly and the electrode assembly, and a sealing tape at least partially surrounding the electrode assembly and the insulating tape.

Description

Technical Field

[0001] This disclosure relates to secondary batteries. Background Technology

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

[0003] The information disclosed in this Background section is intended to enhance the understanding of the background of this disclosure, and therefore may contain information that does not constitute related (prior) art. Summary of the Invention

[0004] The embodiment includes a secondary battery comprising: an electrode assembly including a first electrode, a separator, and a second electrode, the first electrode having a first electrode terminal connected to an insulating strip; a housing having an open side and housing the electrode assembly, the housing being electrically connected to the second electrode; a cover assembly sealing the open side of the housing, the cover assembly being electrically connected to the first electrode terminal; an insulating sheet disposed between the cover assembly and the electrode assembly; and a sealing strip at least partially surrounding the electrode assembly and the insulating strip.

[0005] The sealing strip may include: a base portion surrounding the periphery of the electrode assembly; and a bend portion that is bent at an end of the base portion and rests on an insulating sheet.

[0006] The sealing strip may include: a metal layer comprising a metal material; an insulating layer comprising an insulating material disposed on the metal layer; and a first adhesive layer disposed on the insulating layer.

[0007] The sealing tape may further include a second adhesive layer disposed between the metal layer and the insulating layer, the second adhesive layer bonding the metal layer and the insulating layer together.

[0008] Each of the base section and the bending section includes a metal layer, a second adhesive layer, an insulating layer, and a first adhesive layer.

[0009] The base portion can be attached to the periphery of the electrode assembly via the first adhesive layer, and the bent portion can be attached to the insulating sheet via the first adhesive layer.

[0010] The base portion may include a metal layer, a second adhesive layer, an insulating layer, and a first adhesive layer, and the bending portion may include a metal layer, a second adhesive layer, and an insulating layer.

[0011] The base portion can be attached to the periphery of the electrode assembly via the first adhesive layer, and the bent portion can be placed on the insulating sheet so that the insulating layer faces the insulating sheet.

[0012] The base portion may include a metal layer, a second adhesive layer, an insulating layer, and a first adhesive layer, and the bending portion may include a metal layer and a second adhesive layer.

[0013] The base portion can be attached to the periphery of the electrode assembly via a first adhesive layer, and the bent portion can be attached to the insulating sheet via a second adhesive layer.

[0014] The metal layer can be a coating of metallic material on the insulating layer.

[0015] Each of the base section and the bending section may include a metal layer, an insulating layer, and a first adhesive layer.

[0016] The base portion can be attached to the periphery of the electrode assembly via the first adhesive layer, and the bent portion can be attached to the insulating sheet via the first adhesive layer.

[0017] The base portion may include a metal layer, an insulating layer, and a first adhesive layer, and the bending portion may include a metal layer and an insulating layer.

[0018] The base portion can be attached to the periphery of the electrode assembly via the first adhesive layer, and the bent portion can be placed on the insulating sheet so that the insulating layer faces the insulating sheet.

[0019] The bent portion may include a plurality of cuts spaced apart by a predetermined gap along the circumferential direction, the plurality of cuts being cut in a direction perpendicular to the circumferential direction.

[0020] The length of the bend can be equal to or less than the first length from the inner circumferential surface of the housing to the end portion of the insulating strip connected to the first electrode terminal piece, and can be equal to or greater than the second length from the inner circumferential surface of the housing to the end portion of the diaphragm that is bent in a direction parallel to the bend.

[0021] The length of the bend can be equal to or less than the first length from the inner circumferential surface of the housing to the end portion of the insulating strip connected to the first electrode terminal piece, and can be equal to or greater than the third length from the inner circumferential surface of the housing to the end portion of the insulating sheet.

[0022] The metal layer may include at least one of copper and copper alloys.

[0023] The insulating layer may include at least one of oriented polystyrene, thermoplastic vulcanizate, polyethylene terephthalate, polypropylene, and polyamide.

[0024] These and other aspects and features of this disclosure will be described in the following description of embodiments of this disclosure, or will become apparent from the following description of embodiments of this disclosure.

[0025] According to some embodiments of this disclosure, a sealing strip surrounding the electrode assembly housed in the casing of the secondary battery and an insulating strip connected to the first electrode terminal piece prevent damage to the insulating strip when the casing is joined to the cover assembly by welding.

[0026] According to some embodiments of this disclosure, the outer surface of the sealing strip of the secondary battery is formed of a metal layer to prevent welding heat generated by welding from being transferred to the electrode assembly and the insulating strip.

[0027] According to some embodiments of this disclosure, a metal layer formed on the outer surface of the sealing strip of the secondary battery contacts the inner circumferential surface of the housing to transfer the welding heat generated by welding to the housing, thereby dissipating the welding heat.

[0028] However, the aspects and features of this disclosure are not limited to those described above, and those skilled in the art will clearly understand from the detailed description below that other aspects and features not mentioned will be apparent. Attached Figure Description

[0029] The accompanying drawings illustrate embodiments of the present disclosure and further describe aspects and features of the disclosure together with its detailed description. Therefore, this disclosure should not be construed as limited to the drawings.

[0030] Features will become apparent to those skilled in the art from the detailed description of exemplary embodiments with reference to the accompanying drawings, in which:

[0031] Figure 1 This is a cross-sectional view illustrating an example of a secondary battery according to some embodiments of the present disclosure;

[0032] Figure 2 This is an exploded perspective view illustrating an example of a secondary battery according to some embodiments of the present disclosure;

[0033] Figure 3 This is a cross-sectional view of a first embodiment of a sealing strip in a secondary battery according to some embodiments of the present disclosure;

[0034] Figure 4 This is a cross-sectional view illustrating a second embodiment of the sealing strip of a secondary battery according to some embodiments of the present disclosure;

[0035] Figure 5 This is a cross-sectional view of a third embodiment of the sealing strip of a secondary battery according to some embodiments of the present disclosure;

[0036] Figure 6 This is a cross-sectional view of a fourth embodiment of the sealing strip of a secondary battery according to some embodiments of the present disclosure;

[0037] Figure 7 This is a cross-sectional view of a fifth embodiment of a sealing strip for a secondary battery according to some embodiments of the present disclosure;

[0038] Figure 8 This is a plan view illustrating a cutout formed on a sealing strip of a secondary battery according to some embodiments of the present disclosure;

[0039] Figure 9 This is a plan view illustrating a second embodiment of a secondary battery with cuts formed on a sealing strip according to some embodiments;

[0040] Figure 10 This is a perspective view illustrating an example of placing a sealing strip when the cover assembly of a secondary battery remains open;

[0041] Figure 11 This is a perspective view illustrating an example of the bend in the sealing strip bending when the cover assembly of the secondary battery remains open;

[0042] Figure 12 This is a plan view illustrating an example of bending of the bend in the sealing strip of a secondary battery according to some embodiments of the present disclosure.

[0043] Figure 13 This is a partial cross-sectional view illustrating an example of the bending portion of a sealing strip according to some embodiments of the present disclosure being bent in a secondary battery; and

[0044] Figure 14 This is a cross-sectional view illustrating an example of a cover assembly with a lower insulator connected to a secondary battery according to some embodiments of the present disclosure. Detailed Implementation

[0045] Example embodiments will now be described more fully below with reference to the accompanying drawings; however, example embodiments may be implemented in different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete and will fully convey exemplary embodiments to those skilled in the art.

[0046] In the accompanying drawings, the dimensions of layers and regions may be exaggerated for clarity. It should also be understood that when a layer or element is referred to as "on" another layer or substrate, it may be directly on the other layer or substrate, or there may be intervening layers. Furthermore, it should be understood that when a layer is referred to as "below" another layer, it may be directly below, or there may be one or more intervening layers. Additionally, it will be understood that when a layer is referred to as "between two layers," it may be the only layer between the two layers, or there may be one or more intervening layers. The same reference numerals refer to the same elements throughout.

[0047] In the following, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. The terms or words used in this specification and claims should not be construed as having a general or dictionary meaning, but should be interpreted in a meaning and concept consistent with the technical spirit of the present disclosure, based on the principle that the inventor is capable of properly defining the concepts of the terms to best describe his / her invention as his / her own lexicographer.

[0048] The embodiments described in this specification and the constructions shown in the accompanying drawings are only some of the embodiments of this disclosure and do not represent all the technical spirit, aspects, and features of this disclosure. Accordingly, it should be understood that various equivalents and modifications are possible at the time of filing this application, which can replace or modify the embodiments described herein.

[0049] It will be understood that when an element or layer is referred to as being "on" another element or layer, "connected to," or "attached to" another element or layer, the element or layer may be directly on, connected to, or attached to the other element or layer, or one or more intermediary elements or layers may be present. When an element or layer is referred to as being "directly on" another element or layer, "directly connected to," or "directly attached to" another element or layer, no intermediary element or layer is present. For example, when a first element is described as being "attached" or "connected" to a second element, the first element may be directly attached to or connected to the second element, or the first element may be indirectly attached to or connected to the second element via one or more intermediary elements.

[0050] In the accompanying drawings, the dimensions of various elements, layers, etc., may be exaggerated for clarity of illustration. The same reference numerals denote the same elements. As used herein, the term "and / or" includes any and all combinations of one or more of the items listed. Furthermore, when describing embodiments of this disclosure, the use of "may" means "one or more embodiments of this disclosure." Expressions such as "at least one of" and "any one of" modify the entire list of elements without modifying individual elements in the list when placed after the list of elements. When phrases such as "at least one of A, B, and C," "at least one of A, B, or C," "at least one selected from the group of A, B, and C," or "at least one selected from A, B, and C" are used to specify a list of elements A, B, and C, the phrase may refer to any and all suitable combinations or subsets of A, B, C, A and B, A and C, B and C, or A and B and C, A, B, and C. As used herein, the term "use" and its variations may be considered synonymous with the term "utilize" and its variations, respectively. As used herein, the terms “substantially,” “approximately,” and similar terms are used as approximate terms rather than terms of degree and are intended to describe the inherent biases of measurements or calculations that would be recognized by one of ordinary skill in the art.

[0051] It will be understood that although the terms "first," "second," "third," etc., can be used to describe various elements, components, regions, layers, and / or portions, these elements, components, regions, layers, and / or portions should not be limited by these terms. These terms are used to distinguish one element, component, region, layer, or portion from another element, component, region, layer, or portion. Therefore, without departing from the teachings of the exemplary embodiments, the first element, component, region, layer, or portion discussed below may be referred to as the second element, component, region, layer, or portion.

[0052] In this document, spatial relative terms such as “below,” “under,” “lower,” “above,” and “higher” may be used to describe the relationship between one element or feature as shown in the figures and another (or several) other elements or features. It will be understood that, in addition to the orientation shown in the figures, spatial relative terms are intended to include different orientations of the device in use or operation. For example, if the device in the figures is flipped, it is described as being tilted relative to other elements or features; therefore, the term “below” can include both above and below. The device may be oriented in other ways (rotated 90 degrees or in other orientations), and the spatial relative descriptive terms used herein should be interpreted accordingly.

[0053] The terminology used herein is for the purpose of describing embodiments of this disclosure and is not intended to limit this disclosure. As used herein, unless the context clearly indicates otherwise, the singular forms “a” and “an” are intended to also include the plural forms. It will be further understood that, when used in this specification, the term “comprising” specifies the presence of stated features, integrals, steps, operations, elements, and / or components, but does not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components, and / or groups thereof.

[0054] Furthermore, any numerical range disclosed and / or enumerated herein is intended to include all subranges with the same numerical precision within the enumerated range. For example, the range “1.0 to 10.0” is intended to include, for example, 2.4 to 7.6, all subranges between the stated minimum value of 1.0 and the stated maximum value of 10.0 (inclusive), i.e., all subranges with a minimum value equal to or greater than 1.0 and a maximum value equal to or less than 10.0. Any maximum numerical limit described herein is intended to include all smaller numerical limits, and any minimum numerical limit described in this specification is intended to include all larger numerical limits. Therefore, the applicant reserves the right to amend this specification (including the claims) to expressly detail any subranges included within the range expressly recited herein. All such ranges are intended to be inherently described in this specification such that any amendments used to expressly state any of these subranges will comply with the requirements of local patent law.

[0055] Referring to two compared elements, features, etc., as "identical" can mean that they are "substantially identical." Therefore, the phrase "substantially identical" can include cases with deviations considered low in the art (e.g., deviations below 5%). Additionally, when a parameter is stated to be consistent in a given region, this can mean that it is consistent in terms of average value.

[0056] Throughout this specification, unless otherwise stated, each element may be singular or plural.

[0057] Placing any element "above (or below)" or "above (or below)" another element can mean that the arbitrary element can contact the upper (or lower) surface of the element, and that another element can be located between the element and the arbitrary element disposed on (or below) the element.

[0058] Additionally, it will be understood that when a component is referred to as “connected,” “linked,” or “attached” to another component, these components can be directly “connected,” “linked,” or “attached” to each other, or another component can be “between” these components.

[0059] Throughout this specification, unless otherwise stated, when “A and / or B” is mentioned, it means A, B, or A and B. That is, “and / or” includes any or all combinations of the enumerated items. Unless otherwise stated, when “C to D” is mentioned, it means C and below D.

[0060] Figure 1 This is a cross-sectional view illustrating an example of a secondary battery according to some embodiments of the present disclosure, and Figure 2 This is an exploded perspective view illustrating an example of a secondary battery according to some embodiments of the present disclosure.

[0061] See Figure 1 and Figure 2 According to some embodiments of the present disclosure, a secondary battery 100 may include: an electrode assembly 300 including a first electrode 310, a separator 330, and a second electrode 320, the first electrode 310 including a first electrode terminal piece 311 connected to an insulating strip 312; a housing 200 having an open side and housing the electrode assembly 300, and the housing 200 being electrically connected to the second electrode 320; a cover assembly 400 sealing or closing one open side of the housing 200 and being electrically connected to the first electrode terminal piece 311; an insulating sheet 500 placed / disposed between the cover assembly 400 and the electrode assembly 300; and a sealing strip 610 surrounding the electrode assembly 300 and the insulating strip 312 (e.g., at least partially surrounding the electrode assembly 300 and the insulating strip 312).

[0062] The electrode assembly 300 may include a diaphragm 330 and a first electrode 310 and a second electrode 320 placed between the diaphragm 330, and may be wound in an electrode core shape.

[0063] The first electrode 310 includes a first substrate and a first active material layer on the first substrate. The first electrode tab 311 can extend outward from a first uncoated portion of the first substrate, where the first active material layer is not located, and the first electrode tab 311 can be electrically connected to the cover assembly 400.

[0064] The second electrode 320 includes a second substrate and a second active material layer on the second substrate. A second electrode tab 321 can extend outward from a second uncoated portion of the second substrate, where the second active material layer is not located, and the second electrode tab 321 can be electrically connected to the housing 200. The first electrode tab 311 and the second electrode tab 321 can extend in opposite directions.

[0065] The first electrode 310 can serve as a positive electrode. In such an embodiment, the first substrate can be made of, for example, aluminum foil, and the first active material layer can include, for example, a transition metal oxide. The second electrode 320 can serve as a negative electrode. In such an embodiment, the second substrate can be made of, for example, copper foil or nickel foil, and the second active material layer can include, for example, graphite.

[0066] The diaphragm 330 prevents short circuits between the first electrode 310 and the second electrode 320 while allowing lithium-ion movement between them. The diaphragm 330 can be made of, for example, a polyethylene membrane, a polypropylene membrane, or a polyethylene-polypropylene membrane.

[0067] The housing 200 houses the electrode assembly 300 and, together with the cover assembly 400, forms the appearance of a secondary battery. The housing 200 may have a generally cylindrical body portion and a bottom portion connected to one side (e.g., one end) of the body portion. The housing 200 may be made of a metal such as aluminum, aluminum alloy, or nickel-plated steel.

[0068] The second electrode tab 321 can be coupled and electrically connected to the bottom portion of the housing 200. The end portion of the first electrode tab 311 can be coupled to the protrusion 421 of the terminal plate 420. An insulating tape 312 can be coupled / attached to the portion of the first electrode tab 311 other than the portion coupled to the protrusion 421 of the terminal plate 420. The first electrode tab 311, bent upwards from the electrode assembly 300 (in the illustrated configuration), may contact the cover plate 410 of the cover assembly 400 or the inner peripheral surface of the housing 200, which could cause a short circuit. Therefore, the insulating tape 312 can be attached to the first electrode tab 311.

[0069] The cover assembly 400 may include a cover plate 410 including a through hole 411, a terminal plate 420 placed on the cover plate 410 and including a protrusion 421 inserted into the through hole 411, and an upper insulator 430 disposed between the cover plate 410 and the terminal plate 420.

[0070] The cover plate 410 can be formed in the shape of a disc with a through hole 411 at the center. The cover plate 410 can have a larger diameter than the terminal plate 420 and the upper insulator 430. The cover plate 410 can be welded to the upper side of the housing 200 to seal this open side of the housing 200. Depending on the shape of the housing to which the cover plate 410 is attached, the cover plate 410 can have various shapes.

[0071] The terminal plate 420 may be formed in a circular plate shape having a diameter smaller than that of the cover plate 410, and the terminal plate 420 may include a protrusion 421 that inserts into a through hole 411 in the cover plate 410 at its center. The protrusion 421 of the terminal plate 420 may protrude toward the electrode assembly 300 when inserted into the through hole 411. A first electrode tab 311 may be connected to the protrusion 421 of the terminal plate 420. The shape of the terminal plate 420 may vary depending on the shape of the cover plate 410.

[0072] The first electrode connector 311 can be connected to the protrusion 421 of the terminal block 420, and the second electrode connector 321 can be connected to the housing 200. The terminal block 420 can be used as a positive electrode, and the housing 200 can be used as a negative electrode.

[0073] An upper insulator 430 may be disposed between the cover plate 410 and the terminal plate 420, thereby electrically insulating the cover plate 410 and the terminal plate 420. The cover plate 410 and the terminal plate 420 may be made of a conductive metal material and are electrically connected to the negative electrode of the second electrode contact 321 and the positive electrode of the first electrode contact 311, respectively. The upper insulator 430 insulates the cover plate 410 and the terminal plate 420 to prevent short circuits. The upper insulator 430 may be made of a resin such as polypropylene or polyethylene.

[0074] Similar to the cover plate 410, the upper insulator 430 can be formed in a disc shape with an insertion hole 431 at its center. The protrusion 421 of the terminal plate 420 can penetrate the insertion hole 431 of the upper insulator 430 and the through hole 411 of the cover plate 410 to be placed inside the housing 200. The first electrode tab 311 can be connected to the protrusion 421 of the terminal plate 420 placed inside the housing 200. The outer diameter of the upper insulator 430 can be the same as or similar to the outer diameter of the terminal plate 420. The outer diameter of the cover plate 410 can be larger than the outer diameters of the upper insulator 430 and the terminal plate 420. The diameter of the insertion hole 431 of the upper insulator 430 can be the same as or similar to the diameter of the through hole 411 of the cover plate 410.

[0075] The upper insulator 430 can be placed between the cover plate 410 and the terminal plate 420, and is connected to the cover plate 410 and the terminal plate 420 by heating and pressurizing the cover plate 410 and the terminal plate 420 using a hot melt method.

[0076] An insulating sheet 500 may be disposed between the cover assembly 400 and the electrode assembly 300 to insulate the upper portion of the electrode assembly 300 from the first electrode terminal piece 311. The insulating sheet 500 may be disposed on the upper portion of the electrode assembly 300. The diameter of the insulating sheet 500 may be formed to be smaller than the outer diameter of the electrode assembly 300. The insulating sheet 500 may be made of a resin such as polypropylene or polyethylene.

[0077] A sealing tape 610 may surround the electrode assembly 300 and the insulating tape 312. The sealing tape 610 may be formed in a rectangular shape and attached along the periphery of the electrode assembly 300. The portion of the sealing tape 610 that protrudes upwards to the upper part of the electrode assembly 300 may be bent and placed on the insulating sheet 500. The portion of the sealing tape 610 bent onto the insulating sheet 500 may be arranged to surround the insulating tape 312.

[0078] The sealing tape 610 may include a base portion 610a surrounding the periphery of the electrode assembly 300 and a bent portion 610b bent at the end of the base portion 610a and placed on the insulating sheet 500. The base portion 610a of the sealing tape 610 may first be attached to the electrode assembly 300 while surrounding the periphery of the electrode assembly 300, and then the bent portion 610b, protruding above the electrode assembly 300, may be bent and placed on the insulating sheet 500. The bent portion 610b may be placed along the periphery of the insulating sheet 500. The bent portion 610b may be placed on the insulating tape 312 that is connected / bonded to the first electrode terminal piece 311 and on the insulating sheet 500.

[0079] See Figure 1 and Figure 2 The secondary battery 10 can be coin-shaped or button-shaped. However, it can also be other types of secondary batteries (e.g., cylindrical batteries). See also Figure 1 The first electrode connector 311 can protrude upward to connect to the cover assembly and the second electrode connector 321 can protrude downward to connect to the housing, but both the first electrode connector 311 and the second electrode connector 321 can protrude upward to connect to the cover assembly and the housing, respectively.

[0080] Figure 3 This is a cross-sectional view illustrating a first embodiment of a sealing strip in a secondary battery according to some embodiments of the present disclosure.

[0081] See Figure 1 and Figure 3 According to the first embodiment, the sealing tape 610 may include a metal layer 611 containing a metal material, an insulating layer 612 containing an insulating material and disposed on the metal layer 611, a first adhesive layer 613 disposed on the insulating layer 612, and a second adhesive layer 614 disposed between the metal layer 611 and the insulating layer 612 to ensure adhesion / bonding between the metal layer 611 and the insulating layer 612.

[0082] The metal layer 611 may be formed of a metal foil comprising at least one of copper and copper alloys. The insulating layer 612 may be formed of an insulating film comprising at least one of oriented polystyrene, thermoplastic vulcanizate, polyethylene terephthalate, polypropylene, and polyimide. The first adhesive layer 613 may be formed of an adhesive applied to the insulating layer 612 or an adhesive film attached to the insulating layer 612. The second adhesive layer 614 may be formed of an adhesive applied to at least one of the metal layer 611 and the insulating layer 612 or an adhesive film attached to at least one of the metal layer 611 and the insulating layer 612.

[0083] According to the first embodiment, the metal layer 611, the second adhesive layer 614, the insulating layer 612, and the first adhesive layer 613 of the sealing tape 610 may have the same length. According to some embodiments, the base portion 610a and the bend portion 610b of the sealing tape 610 may be formed as a laminated structure including the metal layer 611, the second adhesive layer 614, the insulating layer 612, and the first adhesive layer 613.

[0084] The base portion 610a of the sealing tape 610 can be attached to the periphery of the electrode assembly 300 via the first adhesive layer 613. The bent portion 610b of the sealing tape 610 can be bent toward the upper part of the insulating sheet 500 and then attached to the insulating sheet 500 via the first adhesive layer 613. A portion of the bent portion 610b can be attached to the insulating tape 312 connected to the first electrode terminal piece 311.

[0085] When the sealing strip 610 is positioned to surround the electrode assembly 300 and the insulating strip 312, the metal layer 611 of the base portion 610a can contact the inner circumferential surface of the housing 200, and the bent portion 610b can be positioned facing the cover plate 410. When the housing 200 is welded to the cover plate 410, the metal layer 611 placed on the outer surface of the sealing strip 610 can protect the electrode assembly 300 and the insulating strip 312. Welding heat generated during welding of the housing 200 and the cover plate 410 can be prevented from being transferred to the electrode assembly 300 and the insulating strip 312. The metal layer 611 can contact the inner circumferential surface of the housing 200 to allow welding heat to be transferred to the housing 200 and dissipated to the outside.

[0086] Figure 4 This is a cross-sectional view illustrating a second embodiment of the sealing strip of a secondary battery according to some embodiments of the present disclosure.

[0087] See Figure 1 and Figure 4According to the second embodiment, the sealing tape 620 may include a metal layer 621 containing a metal material, an insulating layer 622 containing an insulating material and disposed on the metal layer 621, a first adhesive layer 623 disposed on the insulating layer 622, and a second adhesive layer 624 disposed between the metal layer 621 and the insulating layer 622 to ensure adhesion between the metal layer 621 and the insulating layer 622.

[0088] The metal layer 621 may be formed of a metal foil comprising at least one of copper and copper alloys. The insulating layer 622 may be formed of an insulating film comprising at least one of oriented polystyrene, thermoplastic vulcanizate, polyethylene terephthalate, polypropylene, and polyimide. The first adhesive layer 623 may be formed of an adhesive applied to the insulating layer 622 or an adhesive film attached to the insulating layer 622. The second adhesive layer 624 may be formed of an adhesive applied to at least one of the metal layer 621 and the insulating layer 622 or an adhesive film attached to at least one of the metal layer 621 and the insulating layer 622.

[0089] According to the second embodiment, the metal layer 621, the second adhesive layer 624, and the insulating layer 622 of the sealing tape 620 can have the same length, and the first adhesive layer 623 can have a relatively small length. According to some embodiments, the base portion 620a of the sealing tape 620 can be formed as a laminated structure including the metal layer 621, the second adhesive layer 624, the insulating layer 622, and the first adhesive layer 623. The bending portion 620b can be formed as a laminated structure including the metal layer 621, the second adhesive layer 624, and the insulating layer 622.

[0090] The base portion 620a of the sealing tape 620 can be attached to the periphery of the electrode assembly 300 via the first adhesive layer 623. The bent portion 620b of the sealing tape 620 can be bent toward the upper part of the insulating sheet 500 and placed on the insulating sheet 500, so that the insulating layer 622 can face the insulating sheet 500. A portion of the bent portion 620b can be placed on the insulating tape 312 connected to the first electrode terminal piece 311.

[0091] Figure 5 This is a cross-sectional view illustrating a third embodiment of the sealing strip of a secondary battery according to some embodiments of the present disclosure.

[0092] See Figure 1 and Figure 5 According to the third embodiment, the sealing tape 630 may include a metal layer 631 containing a metal material, an insulating layer 632 containing an insulating material and disposed on the metal layer 631, a first adhesive layer 633 disposed on the insulating layer 632, and a second adhesive layer 634 disposed between the metal layer 631 and the insulating layer 632 to ensure adhesion between the metal layer 631 and the insulating layer 632.

[0093] The metal layer 631 may be formed of a metal foil comprising at least one of copper and copper alloys. The insulating layer 632 may be formed of an insulating film comprising at least one of oriented polystyrene, thermoplastic vulcanizate, polyethylene terephthalate, polypropylene, and polyimide. The first adhesive layer 633 may be formed of an adhesive applied to the insulating layer 632 or an adhesive film attached to the insulating layer 632. The second adhesive layer 634 may be formed of an adhesive applied to at least one of the metal layer 631 and the insulating layer 632 or an adhesive film attached to at least one of the metal layer 631 and the insulating layer 632.

[0094] According to the third embodiment, the metal layer 631 and the second adhesive layer 634 of the sealing tape 630 can have the same length, while the insulating layer 632 and the first adhesive layer 633 can have relatively small lengths. The insulating layer 632 and the first adhesive layer 633 can have the same or similar lengths. According to some embodiments, the base portion 630a of the sealing tape 630 can be formed as a laminated structure including the metal layer 631, the second adhesive layer 634, the insulating layer 632, and the first adhesive layer 633. The bending portion 630b can be formed as a laminated structure including the metal layer 631 and the second adhesive layer 634.

[0095] The base portion 630a of the sealing tape 630 can be attached to the periphery of the electrode assembly 300 via the first adhesive layer 633. The bent portion 630b of the sealing tape 630 can be bent toward the upper part of the insulating sheet 500 and then attached to the insulating sheet 500 via the second adhesive layer 634. A portion of the bent portion 630b can be attached to the insulating tape 312 connected to the first electrode terminal piece 311.

[0096] Figure 6 This is a cross-sectional view illustrating a fourth embodiment of the sealing strip of a secondary battery according to some embodiments of the present disclosure.

[0097] See Figure 1 and Figure 6 According to the fourth embodiment, the sealing tape 640 may include a metal layer 641 containing a metal material, an insulating layer 642 containing an insulating material and disposed on the metal layer 641, and a first adhesive layer 643 disposed on the insulating layer 642.

[0098] The metal layer 641 can be integrally formed with the insulating layer 642 by coating the insulating layer 642 with a metallic material including at least one of copper and copper alloys. That is, the metal layer 641 can be a coating of metallic material on the insulating layer 642. According to some embodiments, the metal layer 641 can be coated by applying and rolling a metallic material onto the insulating layer 642. In some embodiments, the metal layer 641 can be formed by depositing a metallic material on the insulating layer 642 using physical vapor deposition (PVD) or chemical vapor deposition (CVD) methods.

[0099] The insulating layer 642 may be formed of an insulating film comprising at least one of oriented polystyrene, thermoplastic vulcanizate, polyethylene terephthalate, polypropylene, and polyimide. The first adhesive layer 643 may be formed of an adhesive applied to the insulating layer 642 or an adhesive film attached to the insulating layer 642.

[0100] According to the fourth embodiment, the metal layer 641, insulating layer 642, and first adhesive layer 643 of the sealing tape 640 may have the same length. According to some embodiments, the base portion 640a and the bend portion 640b of the sealing tape 640 may be formed as a laminated structure including the metal layer 641, insulating layer 642, and first adhesive layer 643.

[0101] The base portion 640a of the sealing tape 640 can be attached to the periphery of the electrode assembly 300 via the first adhesive layer 643. The bent portion 640b of the sealing tape 640 can be bent toward the upper part of the insulating sheet 500 and then attached to the insulating sheet 500 via the first adhesive layer 643. A portion of the bent portion 640b can be attached to the insulating tape 312 connected to the first electrode terminal piece 311.

[0102] Figure 7 This is a cross-sectional view illustrating a fifth embodiment of the sealing strip of a secondary battery according to some embodiments of the present disclosure.

[0103] See Figure 1 and Figure 7 The sealing strip 650 of the fifth embodiment may include a metal layer 651 containing a metal material, an insulating layer 652 containing an insulating material and disposed on the metal layer 651, and a first adhesive layer 653 disposed on the insulating layer 652.

[0104] The metal layer 651 can be integrally formed with the insulating layer 652 by coating the insulating layer 652 with a metallic material including at least one of copper and copper alloys. According to some embodiments, the metal layer 651 can be coated by applying and rolling a metallic material onto the insulating layer 652. In some embodiments, the metal layer 651 can be formed by depositing a metallic material onto the insulating layer 652 using a physical vapor deposition (PVD) or chemical vapor deposition (CVD) method.

[0105] The insulating layer 652 may be formed of an insulating film comprising at least one of oriented polystyrene, thermoplastic vulcanizate, polyethylene terephthalate, polypropylene, and polyimide. The first adhesive layer 653 may be formed of an adhesive applied to the insulating layer 652 or an adhesive film attached to the insulating layer 652.

[0106] According to the fifth embodiment, the metal layer 651 and the insulating layer 652 of the sealing tape 650 can have the same length, and the first adhesive layer 653 can have a relatively small length. According to some embodiments, the base portion 650a of the sealing tape 650 can be formed as a laminated structure including the metal layer 651, the insulating layer 652, and the first adhesive layer 653. The bending portion 650b can be formed as a stacked structure including the metal layer 651 and the insulating layer 652.

[0107] The base portion 650a of the sealing tape 650 can be attached to the periphery of the electrode assembly 300 via the first adhesive layer 653. The bent portion 650b of the sealing tape 650 can be bent toward the upper part of the insulating sheet 500 and placed on the insulating sheet 500, so that the insulating layer 652 can face the insulating sheet 500. A portion of the bent portion 650b can be provided on the insulating tape 312 connected to the first electrode terminal piece 311.

[0108] Figure 8 This is a plan view illustrating a cutout formed on a sealing strip of a secondary battery according to some embodiments of the present disclosure, representing a first embodiment. Figure 9 This is a plan view illustrating a second embodiment of a secondary battery with cuts formed on a sealing strip according to some embodiments. Figure 10 This is a perspective view illustrating an example of placing a sealing strip when the cover assembly of a secondary battery remains open. Figure 11 This is a perspective view illustrating an example of the bend in the sealing strip bending when the cover assembly of the secondary battery remains open.

[0109] See Figures 8 to 11 , Figure 3 The bent portion 610b of the sealing strip 610 shown may include a plurality of slits spaced apart along the circumferential direction X and cut along a direction Y perpendicular to the circumferential direction X. (See also...) Figures 4 to 7 In other embodiments of the sealing strip 620 to 650, a cut is formed.

[0110] See Figure 8 The cut 615 according to the first embodiment can be formed in a straight line shape. See also Figure 9 According to the second embodiment, the cut 615 can be formed in a V shape. However, the shape of the cut can vary, such as U-shaped, polygonal, etc.

[0111] like Figure 10 As shown, in the first stage, the secondary battery can be assembled by attaching a base 610a with a sealing strip 610 around the periphery of the electrode assembly, housing the electrode assembly in the housing 200, and placing an insulating sheet 500 on the electrode assembly. Figure 11 As shown, in the second stage, the secondary battery can be assembled onto the insulating sheet 500 by bending multiple bends 610b cut through the notch 615 towards the insulating sheet 500. A portion of the bends 610b can be attached to the insulating tape 312. The cover plate 410 can be placed and then attached to the housing 200 by welding.

[0112] Figure 12 This is a plan view illustrating an example of the bending of the sealing strip of a secondary battery according to some embodiments of the present disclosure.

[0113] See Figure 12 The length L of the bend 610b of the sealing strip 610 can be equal to or less than the first length D1 from the inner circumferential surface of the housing 200 to the end portion 312a of the insulating strip 312 connected to the first electrode terminal 311. When the length L of the bend 610b is greater than the first length D1, the metal layer of the bend 610b may come into contact with the first electrode terminal 311, which may lead to a short circuit.

[0114] The length L of the bend 610b of the sealing strip 610 can be equal to or greater than the second length D2 of the end portion 331 of the diaphragm 330 bent in a direction parallel to the bend 610b, from the inner circumferential surface of the housing 200 to the diaphragm 330. When the length L of the bend 610b is less than the second length D2, it may become difficult to effectively block the welding heat generated by welding the housing 200 and the cover plate 410.

[0115] See above. Figures 4 to 7 In other embodiments of the described sealing strip 620 to 650, the length of the bend can also be formed as described above.

[0116] Figure 13 This is a partial cross-sectional view illustrating an example of a bent portion of a sealing strip in a secondary battery, according to some embodiments of the present disclosure.

[0117] See Figure 13 The length L of the bent portion 610b of the sealing strip 610 can be equal to or less than the first length D1 from the inner circumferential surface of the housing 200 to the end portion 312a of the insulating strip 312 connected to the first electrode terminal piece 311.

[0118] The length L of the bend 610b of the sealing strip 610 can be equal to or less than the third length D3 from the inner circumferential surface of the housing 200 to the end portion 510 of the insulating sheet 500. When the length L of the bend 610b is less than the third length D3, it may become difficult to effectively block the welding heat generated by the welding between the housing 200 and the cover plate 410.

[0119] See above. Figures 4 to 7 In other embodiments of the described sealing strip 620 to 650, the length of the bend can also be formed as described above.

[0120] Figure 14 This is a cross-sectional view illustrating an example of a cover assembly with a lower insulator connected to a secondary battery according to some embodiments of the present disclosure.

[0121] See Figure 14 According to some embodiments, the secondary battery 100 may further include a lower insulator 440 disposed between the cover plate 410 and the first electrode terminal piece 311 to provide insulation between the cover plate 410 and the first electrode terminal piece 311.

[0122] When the cover plate 410 is connected to the housing 200 as a negative electrode (the cover plate 410 and the housing 200 are the same electrode), the first electrode terminal 311 can be used as a positive electrode, and the lower insulator 440 can prevent short circuits by insulating the cover plate 410 and the first electrode terminal 311. The lower insulator 440 can be made of a resin such as polypropylene or polyethylene.

[0123] Similar to the cover plate 410, the lower insulator 440 can be formed in a disc shape with an insertion hole 441 at its center. A protrusion 421 of the terminal plate 420 can penetrate the insertion hole 441 of the lower insulator 441 and the through hole 411 of the cover plate 410 to be placed inside the housing 200. A first electrode tab 311 can be connected to the protrusion 421 of the terminal plate 420. The outer diameter of the lower insulator 440 can be the same as or similar to the outer diameter of the electrode assembly 300. The outer diameter of the lower insulator 440 can be smaller than the outer diameter of the cover plate 410. The insertion hole 441 of the lower insulator 440 can be formed to a size in which the cover plate 410 is not exposed to the first electrode tab 311. The diameter of the insertion hole 441 of the lower insulator 440 can be equal to or smaller than the diameter of the through hole 411 of the cover plate 410.

[0124] According to some embodiments, the lower insulator 440 may be formed of an insulating strip and attached to the bottom surface of the cover plate 410, or it may be formed of an insulating sheet and attached to the bottom surface of the cover plate 410 by a heat-fusion method.

[0125] The secondary battery houses the electrode assembly through an open side of the casing, and a cover assembly is arranged on that open side of the casing to be joined to the casing by welding. However, when the casing and cover assembly are joined by welding, the insulating tape attached to the first electrode terminal piece 311 may melt due to the welding heat, which may cause insulation degradation.

[0126] According to some embodiments of this disclosure, when the housing and cover assembly are joined, the sealing strip surrounding the electrode assembly housed in the housing of the secondary battery and the insulating strip connected to the first electrode terminal block are protected from damage to the insulating strip by welding.

[0127] According to some embodiments of this disclosure, the outer surface of the sealing strip of the secondary battery is formed of a metal layer to prevent welding heat generated by welding from being transferred to the electrode assembly and the insulating strip.

[0128] According to some embodiments of this disclosure, a metal layer formed on the outer surface of the sealing strip of the secondary battery contacts the inner circumferential surface of the housing to transfer the welding heat generated by welding to the housing and thereby dissipate the welding heat.

[0129] Although this disclosure has been described with reference to the accompanying drawings illustrating embodiments and aspects thereof, this disclosure is not limited thereto. Those skilled in the art to which this disclosure pertains will be able to make various modifications and variations within the spirit and scope of this disclosure and the following claims and their equivalents.

[0130] Thus far, exemplary embodiments have been disclosed. Although specific terminology has been used, it is used in a general and descriptive sense only, and is not intended to be limiting. In some instances, as would be apparent to those skilled in the art at the time of filing this application, unless otherwise specifically stated, features, characteristics, and / or elements described in connection with particular embodiments may be used alone or in combination with features, characteristics, and / or elements described in connection with other embodiments. Therefore, those skilled in the art will understand that various changes in form and detail may be made without departing from the spirit and scope of the invention as set forth in the claims.

Claims

1. A secondary battery, comprising: An electrode assembly includes a first electrode, a diaphragm, and a second electrode, wherein the first electrode has a first electrode tab connected to an insulating strip; A housing having an open side and housing the electrode assembly, the housing being electrically connected to the second electrode; A cover assembly that seals one open side of the housing, the cover assembly being electrically connected to the first electrode tab; An insulating sheet is disposed between the cover assembly and the electrode assembly; as well as A sealing tape, at least partially surrounding the electrode assembly and the insulating tape.

2. The secondary battery according to claim 1, wherein, The sealing strip includes: The base portion surrounds the electrode assembly; and The bending portion is bent at the end of the base portion and is placed on the insulating sheet.

3. The secondary battery according to claim 2, wherein, The sealing strip includes: Metal layer, including metallic materials; An insulating layer, comprising an insulating material, wherein the insulating layer is disposed on the metal layer; and A first adhesive layer is disposed on the insulating layer.

4. The secondary battery according to claim 3, wherein, The sealing strip further includes a second adhesive layer disposed between the metal layer and the insulating layer, the second adhesive layer bonding the metal layer and the insulating layer.

5. The secondary battery according to claim 4, wherein, Each of the base portion and the bending portion includes the metal layer, the second adhesive layer, the insulating layer, and the first adhesive layer.

6. The secondary battery according to claim 5, wherein: The base portion is attached to the periphery of the electrode assembly via the first adhesive layer, and The bent portion is attached to the insulating sheet via the first adhesive layer.

7. The secondary battery according to claim 4, wherein: The base includes the metal layer, the second adhesive layer, the insulating layer, and the first adhesive layer, and The bent portion includes the metal layer, the second adhesive layer, and the insulating layer.

8. The secondary battery according to claim 7, wherein: The base portion is attached to the periphery of the electrode assembly via the first adhesive layer, and The bent portion is placed on the insulating sheet, so that the insulating layer is facing the insulating sheet.

9. The secondary battery according to claim 4, wherein: The base includes the metal layer, the second adhesive layer, the insulating layer, and the first adhesive layer, and The bent portion includes the metal layer and the second adhesive layer.

10. The secondary battery according to claim 9, wherein: The base portion is attached to the periphery of the electrode assembly via the first adhesive layer, and The bent portion is attached to the insulating sheet via the second adhesive layer.

11. The secondary battery according to claim 3, wherein, The metal layer is a coating of metallic material on the insulating layer.

12. The secondary battery according to claim 11, wherein, Each of the base portion and the bending portion includes the metal layer, the insulating layer, and the first adhesive layer.

13. The secondary battery according to claim 12, wherein: The base portion is attached to the periphery of the electrode assembly via the first adhesive layer, and The bent portion is attached to the insulating sheet via the first adhesive layer.

14. The secondary battery according to claim 11, wherein: The base includes the metal layer, the insulating layer, and the first adhesive layer, and The bent portion includes the metal layer and the insulating layer.

15. The secondary battery according to claim 14, wherein: The base portion is attached to the periphery of the electrode assembly via the first adhesive layer, and The bent portion is placed on the insulating sheet, so that the insulating layer is facing the insulating sheet.

16. The secondary battery according to any one of claims 2 to 15, wherein, The bent portion includes a plurality of cuts spaced apart by a predetermined gap along the circumferential direction, the plurality of cuts being cut along a direction perpendicular to the circumferential direction.

17. The secondary battery according to any one of claims 2 to 15, wherein, The length of the bend is equal to or less than a first length from the inner circumferential surface of the housing to the end portion of the insulating strip connected to the first electrode terminal piece, and equal to or greater than a second length from the inner circumferential surface of the housing to the end portion of the diaphragm that is bent in a direction parallel to the bend.

18. The secondary battery according to any one of claims 2 to 15, wherein, The length of the bend is equal to or less than a first length from the inner circumferential surface of the housing to the end portion of the insulating strip connected to the first electrode terminal piece, and equal to or greater than a third length from the inner circumferential surface of the housing to the end portion of the insulating sheet.

19. The secondary battery according to any one of claims 3 to 15, wherein, The metal layer includes at least one of copper and copper alloys.

20. The secondary battery according to any one of claims 3 to 15, wherein, The insulating layer comprises at least one of oriented polystyrene, thermoplastic vulcanizate, polyethylene terephthalate, polypropylene, and polyamide.

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