Insulator and rechargeable battery including same

Abstract

An insulator for a rechargeable battery and a rechargeable battery are disclosed. The insulator may include: a first insulator including a plurality of first through-holes; and a second insulator including a plurality of second through holes. A connection portion between a first through hole of the plurality of second through holes and an adjacent second through hole of the plurality of second through holes overlaps the first through hole.

Description

Technical Field

[0001] The present disclosure relates to a rechargeable battery, and more particularly, to a rechargeable battery including an insulator. Background Art

[0002] In accordance with technological development and demands for mobile devices, the demand for rechargeable batteries as energy sources is increasing.

[0003] The electrode assembly having a core shape may be formed by winding an electrode having a strip shape, and an insulator may be included to minimize or prevent a short circuit between the cap plate and the electrode assembly or damage to the electrode assembly.

[0004] The insulator is inserted by cutting a plastic sheet into a circular shape or a quadrilateral shape according to the shape of the housing. A plurality of through holes may be formed in the insulator so that the electrolyte can be injected. If there are no through holes, the permeation path of the electrolyte may be blocked, which may extend the time required to inject the electrolyte. Therefore, productivity may be reduced.

[0005] If the electrolyte is injected using the through hole, conductive foreign particles such as metal particles within the electrode assembly may float in the electrolyte to cause a small short circuit. Because the small short circuit occurs inside the battery, it may not be easy to repair the small short circuit. Summary of the invention

[0006] Embodiments of the present disclosure provide a rechargeable battery that improves safety by effectively reducing the chance of a small short circuit by removing conductive foreign particles contained in an electrolyte when the electrolyte is injected into the rechargeable battery.

[0007] An insulator for a rechargeable battery according to an embodiment of the present disclosure includes: a first insulator including a plurality of first through holes; and a second insulator including a plurality of second through holes. A connection portion between a first through hole of the plurality of second through holes and an adjacent second through hole of the plurality of second through holes overlaps with the first through hole.

[0008] At least one of the first insulator and the second insulator may have a plate shape.

[0009] The first insulator may have a plate shape, and the second insulator may have a mesh shape.

[0010] At least one of the plurality of first through holes and the plurality of second through holes may be arranged in a matrix form.

[0011] One or more of the plurality of first through holes may have one of a circular shape, an elliptical shape, and a polygonal shape.

[0012] At least one of the first insulator and / or the second insulator may include polypropylene (PP) or polyethylene terephthalate (PET).

[0013] One or more of the plurality of first through holes and one or more of the plurality of second through holes may have a diameter of 100 μm or more.

[0014] An area of ​​the plurality of first through holes may be 40% to 90% of an area of ​​the first insulator.

[0015] A thickness of at least one of the first insulator and the second insulator may be 3 μm to 1000 μm.

[0016] A rechargeable battery according to an embodiment of the present disclosure includes: an insulator for a rechargeable battery according to various embodiments of the present disclosure; an electrode assembly arranged to overlap the insulator; a case accommodating the insulator and the electrode assembly and an electrolyte; and a cap plate configured to seal the case.

[0017] If a plurality of insulators including an insulator having a through hole larger than an impurity size are stacked as in the embodiment of the present disclosure, an insulator having fine holes of a determined size or a desired size may be formed.

[0018] Embodiments of the present disclosure may allow removal of impurities having a determined or desired size while simplifying the manufacturing process of the insulator, thereby minimizing or preventing the occurrence of a small short circuit or the like in a rechargeable battery with improved stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a perspective view of a rechargeable battery according to an embodiment of the present disclosure.

[0020] Figure 2 is a schematic plan view of an insulator according to an embodiment of the present disclosure.

[0021] Figure 3 According to the embodiment of the present disclosure Figure 2 Another view of the insulator.

[0022] Figure 4 is a plan view of a first insulator according to an embodiment of the present disclosure.

[0023] Figure 5 is a series of plan views of an insulator as it undergoes a stacking process according to an embodiment of the present disclosure.

[0024] Figure 6 is a plan view of an insulator according to an embodiment of the present disclosure.

[0025] Figure 7 is a plan view of an insulator according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0026] Hereinafter, embodiments of the present disclosure will be described more fully with reference to the attached drawings so that those skilled in the art can implement the embodiments. The present disclosure can be modified in various different ways, all without departing from the spirit or scope of the present disclosure.

[0027] Since sizes and thicknesses of constituent members shown in the drawings are given for better understanding and ease of description, the present disclosure is not limited to the sizes and thicknesses shown.

[0028] In the accompanying drawings, for the sake of clarity, the sizes of various elements, layers, films, panels, areas, etc. can be enlarged. In the accompanying drawings, for better understanding and ease of description, the thickness of some layers and areas is enlarged. The same reference numerals indicate the same elements. As used herein, the term "and / or" includes any and all combinations of one or more of the associated enumerated items. Further, the use of "may" in describing the embodiments of the present disclosure relates to "one or more embodiments of the present disclosure". Expressions such as "at least one of..." and "any of..." before the list of elements modify the entire list of elements and do not modify the individual elements in the list. For example, the expression "at least one of a, b or c" means only a, only b, only c, both a and b, both a and c, both b and c, all of a, b and c or their variations. As used herein, the term "use" can be regarded as synonymous with the term "utilize". As used herein, the terms "substantially", "about" and similar terms are used as approximate terms rather than degree terms, and are intended to take into account the inherent variations of measured values ​​or calculated values ​​that will be recognized by those of ordinary skill in the art.

[0029] It will be understood that although the terms "first," "second," "third," etc., are used herein to describe various elements, components, regions, layers, and / or sections, these elements, components, regions, layers, and / or sections should not be limited by these terms. These terms are used to distinguish one element, component, region, layer, or section from another element, component, region, layer, or section. Thus, a first element, component, region, layer, or section discussed below may be referred to as a second element, component, region, layer, or section without departing from the teachings of the example embodiments.

[0030] It will be understood that when an element or layer, such as a film, zone, region, or substrate, is referred to as being "on," "connected to," or "coupled to," another element or layer, it may be directly on, connected to, or coupled to the other element or layer, or one or more intervening elements or layers may also be present. When an element or layer is referred to as being "directly on," "directly connected to," or "directly coupled to," another element or layer, no intervening elements or layers are present. For example, when a first element is described as being "coupled" or "connected" to a second element, the first element may be directly coupled or connected to the second element, or the first element may be indirectly coupled or connected to the second element via one or more intervening elements.

[0031] For ease of description, spatially relative terms such as "below," "below," "down," "above," and "on" may be used herein to describe the relationship of one element or feature to another element or feature as shown in the figures. It will be understood that spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figure is flipped, an element described as being "below" or "below" other elements or features may be oriented to be "above" or "on" other elements or features. Thus, the term "below" may encompass both above and below orientations. The device may be oriented in other ways (rotated 90 degrees or in other orientations), and the spatially relative descriptors used herein should be interpreted accordingly.

[0032] The terms used herein are for the purpose of describing embodiments of the present disclosure and are not intended to limit the present disclosure. As used herein, the singular form is intended to also include the plural form, unless the context clearly indicates otherwise. In addition, unless there is a clear description to the contrary, the word "include" and variants such as "include" and / or "include" will be understood to mean including or having the elements, features, integers, steps, operations, parts and / or its groups, but do not exclude any other elements, features, integers, steps, operations, parts and / or its groups.

[0033] In addition, any numerical range disclosed and / or recorded herein is intended to include all sub-ranges of the same numerical precision contained in the range of the record. For example, the range of "1.0-10.0" is intended to include (and include) all sub-ranges between the minimum value 1.0 recorded and the maximum value 10.0 recorded, that is, with a minimum value equal to or greater than 1.0 and a maximum value equal to or less than 10.0, for example, such as 2.4-7.6. Any maximum numerical limit recorded herein is intended to include all lower numerical limits contained therein, and any minimum numerical limit recorded in this specification is intended to include all higher numerical limits contained therein. Therefore, the applicant reserves the right to modify this specification (including claims) to clearly record any sub-range contained in the range clearly recorded herein. All such ranges are intended to be inherently described in this specification so that the modifications made to clearly record any such sub-ranges can meet the requirements.

[0034] Figure 1 is a perspective view of a rechargeable battery according to an embodiment of the present disclosure.

[0035] like Figure 1 As shown in , a rechargeable battery 1000 according to an embodiment of the present disclosure may include: an electrode assembly 10; a shell 20 containing the electrode assembly 10; a cover assembly 30 connected to an opening of the shell 20 through a gasket 40 and electrically connected to the electrode assembly 10; an insulator 50 provided between the cover assembly 30 and the electrode assembly 10; and a center pin 60 arranged or located at the center of the electrode assembly 10.

[0036] The electrode assembly 10 may include a first electrode 11, a separator 12, and a second electrode 13, which may be stacked (eg, sequentially). The electrode assembly 10 may be a cylindrical core-shaped electrode assembly in which the first electrode 11, the separator 12, and the second electrode 13 are stacked and then wound around a center pin 60.

[0037] The first electrode 11 may include: a first electrode active portion 11a where an active material layer (e.g., a transition metal oxide (LiCoO2, LiNiO2, or LiMn2O4, etc.) is formed on both surfaces of a conductive substrate (or a current collector) formed of a thin metal plate; and a first electrode uncoated portion 11b, which is a portion where the substrate is exposed due to the absence of an active material layer and is formed along an edge of the first electrode active portion 11a. An end portion of the active material layer may be covered with an insulating layer or the like, and the first electrode uncoated portion 11b may be a portion made of the substrate (e.g., a portion made only of the substrate) without any other layers such as an insulating layer and an active material layer.

[0038] The second electrode 13 may include: a second electrode active portion 13a in which an active material layer (e.g., graphite or carbon, etc.) is formed on both surfaces of a substrate formed of a thin metal plate; and a second electrode uncoated portion 13b which is a portion where the substrate is exposed due to the absence of an active material layer and formed along an edge of the second electrode active portion 13a. The end of the active material layer may be covered with an insulating layer or the like, and the second electrode uncoated portion 13b may be a portion made of the substrate (e.g., a portion made only of the substrate) without any other layers such as an insulating layer and an active material layer.

[0039] For example, the first electrode 11 may be a positive electrode, and the second electrode 13 may be a negative electrode.

[0040] In some embodiments, the substrate of the first electrode 11 may be aluminum (Al), and the substrate of the second electrode 13 may be copper (Cu), nickel (Ni), or an alloy of copper and nickel.

[0041] The separator 12 may be disposed or located between the first electrode 11 and the second electrode 13, and may insulate the first electrode 11 from the second electrode 13. The separator 12 may use polyethylene, polypropylene, polyvinylidene fluoride, or a multilayer film of two or more layers thereof, and may use a mixed multilayer film such as a polyethylene / polypropylene 2-layer separator, a polyethylene / polypropylene / polyethylene 3-layer separator, or a polypropylene / polyethylene / polypropylene 3-layer separator.

[0042] In the core state, the first electrode collector plate 11 d may be connected to the first electrode uncoated portion 11 b of the electrode assembly 10 , and the second electrode collector plate 13 d may be connected to the second electrode uncoated portion 13 b of the battery assembly 10 .

[0043] The second electrode collector plate 13 d may contact the case 20 , but the width of the first electrode collector plate 11 d may be formed smaller than that of the second electrode collector plate 13 d so that the first electrode collector plate 11 d does not contact the case 20 .

[0044] The first electrode uncoated portion 11b of the first electrode 11 may be bent toward the center pin 60 as the center of the electrode assembly 10, and adjacent first electrode uncoated portions 11b may be stacked overlapping each other to be electrically connected to each other. For example, the embodiment of the present disclosure may be easily folded by forming a chamfered portion.

[0045] The first electrode uncoated portion 11 b may be electrically connected to the first electrode current collector plate 11 d in an overlapping state.

[0046] The first electrode uncoated portion 11b may include one surface contacting and electrically connected to the first electrode current collector plate 11d and another surface facing an end portion of the second electrode 13. The other surface of the first electrode uncoated portion 11b may be spaced apart from the end portion of the second electrode 13.

[0047] An insulating layer (not shown) may be formed on at least one of one surface and the other surface of the first electrode uncoated portion 11 b .

[0048] The lead tab 37 may be electrically connected to the first electrode current collector plate 11 d .

[0049] One end of the lead tab 37 may be connected to the first electrode collector plate 11d by welding, and the other end of the lead tab 37 may be electrically connected to the cap assembly 30. The lead tab 37 may be bent so that one surface of the lead tab 37 faces the electrode assembly 10 to increase an area of ​​contact with the electrode assembly 10.

[0050] The insulator 50 may be arranged to overlap the electrode assembly 10. The insulator 50 having an opening exposing the center pin 60 may be disposed or positioned on the first electrode current collector plate 11d.

[0051] The insulator 50 may be formed larger than the first electrode collector plate 11d so that the insulator 50 contacts the inner surface of the case 20. If the insulator 50 is formed larger than the first electrode collector plate 11d, a predetermined gap having a width of the insulator 50 protruding from the first electrode collector plate 11d may be formed between the first electrode collector plate 11d and the case 20. The predetermined gap between the first electrode collector plate 11d and the case 20 may minimize or prevent a short circuit caused by contact between the first electrode collector plate 11d and the case 20.

[0052] The insulator 50 may be formed of multiple layers, and will be described in detail in detail below. Figure 2 to Figure 4 Describe in detail.

[0053] Figure 2 is a schematic plan view of an insulator 500 according to an embodiment of the present disclosure. Figure 2 The insulator 500 may be similar to Figure 1 Insulator 50. Figure 3 for Figure 2 Another view of the insulator, and Figure 4 is a plan view of a first insulator according to an embodiment of the present disclosure.

[0054] like Figure 2 and Figure 3As shown in , the insulator 500 according to an embodiment of the present disclosure may include a first insulator 501 and a second insulator 502 overlapping the first insulator 501 .

[0055] The first insulator 501 and / or the second insulator 502 may include any material that allows the electrolyte to be injected into the housing 20 through the through holes of the first insulator 501 and / or the second insulator 502. For example, the first insulator 501 and / or the second insulator 502 may include polypropylene (PP) or polyethylene terephthalate (PET). The thickness of the first insulator 501 and / or the second insulator 502 may be 3 μm to 1000 μm.

[0056] The first and second insulators 501 and 502 may have a plate shape or a mesh shape, and a plurality of first and second through holes S1 and S2 may be respectively formed in the first and second insulators 501 and 502. The first and second through holes S1 and S2 may be disposed or arranged in a matrix form.

[0057] For convenience of description, if the width of the connection portion SP1 or SP2 between vias is smaller than the diameter of the via, the mesh shape may be formed such that the width of the connection portion SP1 or SP2 between vias is narrower than the diameter of the via.

[0058] The first through hole S1 and the second through hole S2 may be randomly arranged or positioned. In some embodiments, the first through hole S1 and the second through hole S2 may be positioned at regular intervals and sizes. When a plurality of insulators are stacked to form fine holes as will be described later, arranging the fine holes at regular intervals and sizes may form fine holes having a predetermined size, rather than arranging the fine holes in random shapes.

[0059] Although Figure 2 and Figure 3 The example through hole S1 or S2 has a quadrilateral planar shape, but the present disclosure is not limited thereto, and the through hole S1 may have various shapes, such as Figure 4 As shown in the embodiment of FIG. 5 , a polygonal shape (eg, a diamond shape), a circular shape, and an elliptical shape may be used. Since the first insulator 501 and the second insulator 502 may have through holes of the same shape, only the first insulator 501 is shown in FIG. Figure 4 middle.

[0060] See again Figure 2 and Figure 3, the area of ​​each first through hole S1 (e.g., the entire area) and the area of ​​each second through hole S2 (e.g., the entire area) constitute or add up to 40% to 90% of the area of ​​the first insulator 501 and the second insulator 502, and the diameter (or width) D1 of one or more of the through holes S1 and S2 may be larger than the size of the impurities, so that the impurities can pass through the through holes S1 and S2. For example, the diameter D1 of one or more of the through holes S1 and S2 may be greater than 100 μm.

[0061] The first through hole S1 may overlap with the connection portion SP2 between the adjacent second through holes S2, and the second through hole S2 may overlap with the connection portion SP1 between the adjacent first through holes S1. For example, the width W1 of the connection portion SP1 between the adjacent first through holes S1 may be smaller than the size of the second through hole S2 overlapping with the connection portion SP1, and the width W2 of the connection portion SP2 between the adjacent second through holes S2 may be smaller than the size of the first through hole S1 overlapping with the connection portion SP2. If the width W1 or W2 is larger than the size of the second through hole S2 or the first through hole S1, respectively, the through holes (e.g., all through holes) may be blocked so that fine holes are not formed.

[0062] The above embodiment is described as an example in which the first through hole S1 and the second through hole S2 are disposed or arranged to be misaligned with each other so that the first through hole S1 overlaps with the connecting portion SP2 between the adjacent second through hole S2 and the second through hole S2 overlaps with the connecting portion SP1 between the adjacent first through hole S1, but the present disclosure is not limited thereto.

[0063] Figure 5 1 is a series of plan views of the insulator 510 as it undergoes a stacking process according to an embodiment of the present disclosure.

[0064] like Figure 5 As shown in , a plurality of insulators (eg, the same insulators) may be stacked to form an insulator 510. At least one of the plurality of insulators may be stacked in a state where it is rotated at an angle (eg, a predetermined angle) relative to a virtual center line passing through the center of the lower insulator.

[0065] The insulator 510 may be formed by stacking a first insulator 501, a second insulator 502, and a third insulator 503. The first insulator 501, the second insulator 502, and the third insulator 503 may be insulators having the same size of through holes and the same arrangement or layout of the through holes.

[0066] The second insulator 502 may be stacked on the first insulator 501. The second insulator 502 may be rotated at an angle (e.g., a predetermined angle) relative to a virtual center line of the first insulator 501 on which the second insulator 502 is stacked. The rotation may allow a connection portion SP2 between adjacent second through holes SS of the second insulator 502 to overlap with the first through hole S1 of the first insulator 501, and allow a connection portion SP1 between adjacent first through holes S1 to overlap with the second through hole SS.

[0067] For example, the connection portion SP2 between the adjacent second through holes SS may block a portion of the first through hole S1 so that the size of the first through hole S1 is reduced.

[0068] For example, the third insulator 503 may be stacked on the second insulator 502, and the third insulator 503 may be rotated at an angle (e.g., a predetermined angle) based on the second through hole SS of the second insulator 502 on which the third insulator 503 is stacked. The rotation may allow the connection portion SP3 between the third through holes SSS of the third insulator 503 to overlap with the second through hole SS.

[0069] For example, the connection portion SP3 between the adjacent third through holes SSS may block a portion of the first through hole S1 or the second through hole SS, so that the size of the first through hole S1 or the second through hole SS may be reduced.

[0070] like Figure 5 Rotation of the stacked insulator shown in FIG. 5 may allow pores (or fine holes) of various sizes to be formed.

[0071] In one or more embodiments, the sizes of the stacked vias are the same. However, the present disclosure is not limited thereto, and the sizes of the stacked vias may be different from each other, such as Figure 6 and Figure 7 as shown in .

[0072] Figure 6 and Figure 7 5 is a plan view of insulators 520 and 530 according to an embodiment of the present disclosure.

[0073] If the size of the first through hole S1 of the insulator 520 or 530 is larger than the size of the second through hole S2 of the insulator 520 or 530, as shown in FIG. Figure 6 and Figure 7 As shown in FIG. 5 , a plurality of connection portions SP2 including connection portions SP2 between adjacent second through holes S2 may overlap the first through hole S1. For example, three or more small holes SS1 may be formed by overlapping the first insulator 501a and the second insulator 502a.

[0074] Although the above embodiments describe that the first insulator and the second insulator overlap each other or the first to third insulators overlap each other, the present disclosure is not limited thereto, and the fourth insulator and the fifth insulator may be additionally stacked on the first to third insulators. For example, the connection portion of the additionally stacked insulator may be arranged or disposed to overlap with the small hole previously formed due to the stacking.

[0075] In some embodiments, the through-hole may be divided into small holes of reduced size according to the number of times the connection portions of the stack of insulators overlap in one through-hole or the number of connection portions.

[0076] For example, Figure 6 and Figure 7 As shown in , if one connection portion overlaps, the first through hole can be divided into two small holes, and if two connection portions overlap, the first through hole can be divided into three or four small holes.

[0077] Since the insulator is additionally stacked, the small pores can be divided into smaller pores and become fine pores. In some embodiments, the small pores can be made smaller so that fine particles floating in the electrolyte cannot pass through. For example, the insulator can be additionally stacked until fine pores with a certain size or a desired size are formed.

[0078] In some embodiments, the fine hole is formed by stacking a plurality of insulators having a plurality of through holes including a through hole having a size larger than the size of the impurity, so that the fine hole has a size that helps to minimize or prevent the impurity from passing through the fine hole. For example, the size of the through hole can be 100 μm or more and can be larger than the size of the impurity. By stacking a plurality of insulators, the diameter (or width) of the fine hole that can be formed can be less than 100 μm depending on the size of the impurity.

[0079] The benefit provided by one or more embodiments of the present disclosure is that, when the electrolyte is injected, the fine pores of the insulator can help minimize or prevent impurities in the electrolyte from penetrating into the interior. In this regard, impurities in the electrolyte can be filtered by the fine pores of the insulator or can be trapped in the fine pores without floating.

[0080] See again Figure 1 The lead tab 37 may contact a first auxiliary plate 34 of the cap assembly 30 described later to be connected to the first electrode collector plate 11 d of the electrode assembly 10 through the opening 51 of the insulator 50 .

[0081] In some embodiments, the electrode assembly 10 is wound around the center pin 60 , and the center pin 60 is disposed or positioned at the center of the electrode assembly 10 , and may be disposed or positioned parallel to a direction in which the electrode assembly 10 is inserted into the case 20 .

[0082] If the center pin 60 is subjected to a frontal compression load or a local impact load acting on the outside of the rechargeable battery, the center pin 60 may be deformed (e.g., minimally deformed) or may maintain a shape close to a pre-deformed shape. The center pin 60 may have a hollow cylindrical shape. For example, the center pin 60 may be used as a moving path for gas generated inside. In some embodiments, the center pin 60 may be omitted.

[0083] The center pin 60 may be formed of a material having a certain rigidity (e.g., a metal having conductivity) to resist external impact and deform (e.g., deform minimally). For example, the metal having conductivity may be steel, steel alloy, aluminum, or aluminum alloy, etc. In some embodiments, the center pin 60 has conductivity, and both ends of the center pin 60 may be installed to electrically insulate the first electrode collector plate 11d from the second electrode collector plate 13d.

[0084] In some embodiments, the insulating pad 52 may be disposed or located between the lower end of the center pin 60 and the second electrode collector plate 13d corresponding to the lower end of the center pin 60. The upper end of the center pin 60 may pass through the through hole formed at the center of the first electrode collector plate 11d in an insulating state to be supported by the insulator 50. For example, the upper end of the center pin 60 may be spaced apart from the through hole of the first electrode collector plate 11d, or an insulating member (not shown) may be interposed between the upper end of the center pin 60 and the through hole of the first electrode collector plate 11d. Therefore, the movement of the center pin 60 may be restricted in the length direction of the center pin 60, and the center pin 60 may maintain a stable state at the center of the electrode assembly 10.

[0085] One side of the case 20 may be opened so that the electrode assembly 10 together with the electrolyte is inserted into the case 20. The case 20 may be formed to have approximately the same shape as the core type electrode assembly 10.

[0086] For example, the housing 20 may include a circular bottom portion and a cylindrical side portion extending upward from the bottom portion by a predetermined length. During the assembly process of the rechargeable battery, the upper portion of the cylindrical housing may be opened. For example, during the assembly process of the rechargeable battery, the electrode assembly may be inserted into the cylindrical housing, and then the electrolyte may be injected into the cylindrical housing.

[0087] The electrolyte may allow lithium ions generated by the electrochemical reaction in the first electrode and the second electrode inside the battery to move. The electrolyte may include a lithium salt such as LiPF6 or LiBF4 and an organic solvent such as EC, PC, DEC or EMC. The electrolyte may be in a liquid state, a solid state or a gel state.

[0088] The case 20 may be connected to the second electrode collector plate 13d of the electrode assembly to serve as a second electrode terminal of the rechargeable battery. For example, the case 20 may be formed of a conductive metal such as aluminum, aluminum alloy, or nickel-plated steel.

[0089] The cap assembly 30 may be disposed or located at the opening of the case 20, and may be coupled to the case 20 with the gasket 40 interposed therebetween. The gasket 40 may insulate the case 20 and the cap assembly 30, and may seal the interior of the case 20 accommodating the electrode assembly 10 and the electrolyte.

[0090] The cap assembly 30 may include a cap plate 31 , a positive temperature coefficient element 35 , a gas exhaust plate 32 , an insulating member 33 , a first auxiliary plate 34 , and a second auxiliary plate 38 .

[0091] The first auxiliary plate 34 may be electrically connected to the lead tab 37 of the electrode assembly, and may be coupled to the lead tab 37 by welding.

[0092] The second auxiliary plate 38 may be stacked on the first auxiliary plate 34 to be electrically connected to the first auxiliary plate 34, and may be coupled to the first auxiliary plate 34 by welding. The second auxiliary plate 38 may be disposed or located at the center of the electrode assembly 10 corresponding to the center pin 60, and may have a through hole exposing the first auxiliary plate 34.

[0093] The exhaust plate 32 may be disposed or located above the second auxiliary plate 38 with the insulating member 33 interposed therebetween. An edge of the exhaust plate 32 may be inserted into the gasket 40 to be coupled thereto.

[0094] The exhaust plate 32 may include an exhaust member 32a disposed or located at a portion corresponding to the center pin 60. The exhaust member 32a may protrude from the exhaust plate 32 toward the electrode assembly 10, and may contact the first auxiliary plate 34 through the through hole to be electrically connected to the first auxiliary plate 34. The exhaust plate 32 may have a notch 32b around the exhaust member 32a to guide the exhaust member 32a to be broken.

[0095] The vent 32a may be ruptured under a predetermined pressure condition to release internal gas to the outside and block electrical connection with the first auxiliary board 34. In some embodiments, when the internal pressure of the housing 20 increases due to the generation of gas, the notch 32b may be ruptured in advance so that the gas is discharged to the outside through a discharge port 31d described later to help minimize or prevent explosion of the rechargeable battery.

[0096] For example, if the abnormal reaction continues to damage the exhaust member 32a, the electrical connection between the exhaust plate 32 and the first auxiliary plate 34 may be disconnected. In some other embodiments, the electrical connection between the cover plate 31 electrically connected to the exhaust plate 32 and the first auxiliary plate 34 may be disconnected so that no current flows.

[0097] The cap plate 31 may include: a center plate 31a corresponding to the center pin 60 as the center of the electrode assembly 10; a plurality of branch portions 31b extending from the center plate 31a toward the gasket 40; and a coupling plate 31c connecting ends of the branch portions 31b and inserted into the gasket 40 to be coupled to the gasket 40. Spaces between adjacent branch portions 31b may be opened to the outside to form exhaust ports 31d for exhausting internal gas. The cap plate 31 may seal the case 20.

[0098] The branch portion 31b may be bent from the coupling plate 31c to be connected to the central plate 31a, so that the center of the cap plate 31 protrudes to the outside of the case 20. The cap plate 31 may be electrically connected to the first electrode collector plate 11d through the exhaust plate 32, the second auxiliary plate 38, the first auxiliary plate 34, and the lead tab 37, so that the cap plate 31 serves as a first electrode terminal of the rechargeable battery. For example, if the center of the cap plate 31 is formed to protrude to the outside of the case 20, terminal connection with an external device may be facilitated.

[0099] In some embodiments, the positive temperature coefficient element 35 may be formed along the second plate of the cover plate 31 and may be inserted into the gasket 40 between the second plate of the cover plate and the edge of the exhaust plate in a stacked state to be coupled to the gasket 40 .

[0100] The positive temperature coefficient element 35 may be installed between the cap plate 31 and the exhaust plate 32 to adjust current flow between the cap plate 31 and the exhaust plate 32 according to the internal temperature of the rechargeable battery.

[0101] If the internal temperature is within a predetermined range, the positive temperature coefficient element 35 may function as a conductor to electrically connect the cap plate 31 and the exhaust plate 32. However, if the internal temperature exceeds a predetermined temperature, the positive temperature coefficient element 35 may have a resistance that increases to infinity. For example, the positive temperature coefficient element 35 may block the flow of a charging current or a discharging current between the cap plate 31 and the exhaust plate 32.

[0102] With the electrode assembly 10 inserted into the shell 20 , the exhaust plate 32 , the positive temperature coefficient element 35 , and the cap plate 31 may be inserted into the gasket 40 at the edge of the cap assembly 30 in a stacked state, and then the cap assembly 30 may be inserted into the opening of the shell 20 .

[0103] For example, the cap assembly 30 may be fixed to the opening of the housing 20 by a crimping process. In some embodiments, the crimping portion 21 and the crimping portion 22 may be formed adjacent to the opening of the housing 20. The crimping portion 21 may be formed by a crimping process. The crimping portion 21 may have a structure in which the crimping portion 21 is recessed toward the center in the radial direction of the housing 20 at the upper side of the housing 20 in a state in which the electrode assembly 10 is accommodated in the housing 20, and the crimping portion 21 may minimize or prevent the electrode assembly 10 from moving up and down.

[0104] The crimping portion 22 may have a structure that protrudes relatively from the crimping portion 21 in a radial direction and may be connected to the crimping portion 21 so that the crimping portion 22 holds the outer peripheral surface of the cover assembly 30 and the upper and lower surfaces connected to the outer peripheral surface through the gasket 40 .

[0105] While the present disclosure has been described in connection with what are presently considered to be practical embodiments, it is to be understood that the disclosure is not limited to the disclosed embodiments, but is intended to cover various modifications and equivalent arrangements included within the scope of the appended claims and their equivalents.

[0106] Description of Reference Numerals

[0107] 10: Electrode assembly 11: First electrode

[0108] 12: diaphragm 13: second electrode

[0109] 20: Shell 21: Rolling part

[0110] 22: Crimp part 30: Cover assembly

[0111] 31: Cover plate 31a: Center plate

[0112] 31b: Branch part 31c: Connecting plate

[0113] 31d: Exhaust port 32: Exhaust plate

[0114] 32a: exhaust piece 32b: notch

[0115] 33: Insulating member 34: First auxiliary plate

[0116] 35: Positive temperature element 37: Lead lug

[0117] 38: Second auxiliary plate 40: Gasket

[0118] 50: Insulator 51: Opening

[0119] 52: Insulation pad 60: Center pin

Claims

1. An insulator for a rechargeable battery, comprising: A first insulator including a plurality of first through holes; and The second insulator includes a plurality of second through holes, A connecting portion between a first through hole among the plurality of second through holes and an adjacent second through hole among the plurality of second through holes overlaps with the first through hole. 2 . The insulator for a rechargeable battery according to claim 1 , wherein at least one of the first insulator and the second insulator has a plate shape. 3 . The insulator for a rechargeable battery according to claim 1 , wherein the first insulator has a plate shape, and the second insulator has a mesh shape. 4 . The insulator for the rechargeable battery according to claim 1 , wherein at least one of the plurality of first through holes and the plurality of second through holes are arranged in a matrix form. 5 . The insulator for a rechargeable battery according to claim 1 , wherein one or more of the plurality of first through holes has one of a circular shape, an elliptical shape, and a polygonal shape. 6 . The insulator for a rechargeable battery according to claim 1 , wherein at least one of the first insulator and / or the second insulator comprises polypropylene or polyethylene terephthalate. 7 . The insulator for a rechargeable battery according to claim 1 , wherein a diameter of one or more of the plurality of first through holes and one or more of the plurality of second through holes is 100 μm or more. 8 . The insulator for a rechargeable battery according to claim 7 , wherein an area of ​​the plurality of first through holes is 40% to 90% of an area of ​​the first insulator. 9 . The insulator for a rechargeable battery according to claim 1 , wherein a thickness of at least one of the first insulator and the second insulator is 3 μm to 1000 μm.

10. A rechargeable battery comprising: The insulator for the rechargeable battery according to any one of claims 1 to 9; an electrode assembly arranged to overlap the insulator; A shell, containing the insulator, the electrode assembly and the electrolyte; as well as A cover plate is configured to seal the housing.

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