Rechargeable battery

Abstract

A rechargeable battery includes: an electrode assembly including a first electrode, a second electrode, a separator between the first electrode and the second electrode, a first electrode tab and a second electrode tab connected to the first electrode and the second electrode, respectively; a housing accommodating the electrode assembly, the first electrode tab being connected to the housing; and a cap assembly sealing an opening of the housing. The cap assembly includes: a cap plate coupled to the housing and covering the opening; and a terminal plate coupled to the cover plate. The terminal plate includes: a flange portion coupled to the cap plate and electrically insulated from the cap plate; and a tab connection portion protruding from the flange portion toward the electrode assembly, extending into a terminal opening in the cap plate and connected to the second electrode tab. An inner surface of the tab connection portion has a height difference with an inner surface of the cap plate.

Description

Technical Field

[0001] Aspects of embodiments of the present invention relate to rechargeable batteries. Background Art

[0002] Unlike primary batteries that are not designed to be recharged, rechargeable batteries (also known as secondary batteries) are designed to be repeatedly charged and discharged. Small-capacity rechargeable batteries can be used in small portable electronic devices such as mobile phones, notebook computers, and camcorders, and large-capacity rechargeable batteries can be used as a motor drive power source for hybrid vehicles and / or electric vehicles, for example.

[0003] Some examples of rechargeable batteries include nickel-cadmium (Ni-Cd) batteries, nickel-metal hydride (Ni-MH) batteries, lithium (Li) batteries, and lithium-ion (Li-ion) batteries. Lithium-ion rechargeable batteries have an operating voltage about three times higher than nickel-cadmium batteries and nickel-metal hydride batteries, and are often used as power sources for portable electronic devices. In addition, lithium-ion secondary batteries are widely used due to their relatively high energy density per unit weight.

[0004] As the demand for wearable devices such as headphones, in-ear headphones, smart watches, and body-attached medical devices using Bluetooth increases, the demand for ultra-small rechargeable batteries with high energy density is increasing.

[0005] Such an ultra-small rechargeable battery should achieve the required electrical capacity within a limited size, achieve an efficient structure while increasing the effective weight, and improve the stability of the structure.

[0006] The above information disclosed in this Background section is for enhancement of understanding of the background of the invention and therefore it may contain information that is not prior art. Summary of the invention

[0007] According to an embodiment of the present invention, there is provided a rechargeable battery having a structure that prevents or significantly reduces the risk of a short circuit between an electrode tab connected to a terminal plate and a cap plate having a polarity different from that of the electrode tab.

[0008] According to an embodiment of the present invention, a rechargeable battery includes: an electrode assembly including a first electrode, a second electrode, a separator between the first electrode and the second electrode, a first electrode tab connected to the first electrode, and a second electrode tab connected to the second electrode, the electrode assembly having a first end and a second end opposite to each other; a housing accommodating the electrode assembly and facing the first end of the electrode assembly, the first electrode tab being connected to the housing; and a cap assembly closing and sealing an opening of the housing. The cap assembly includes: a cap plate coupled to the housing, covering the opening and facing the second end of the electrode assembly; and a terminal plate coupled to the cap plate. The terminal plate includes: a flange portion coupled to the cap plate and electrically insulated from the cap plate; and a tab connection portion protruding from the flange portion toward the electrode assembly, extending into the terminal opening in the cap plate, and connected to the second electrode tab. There is a height difference between the inner surface of the tab connection portion and the inner surface of the cap plate.

[0009] The inner surface of the tab connection portion may protrude farther toward the second end of the electrode assembly than the inner surface of the cap plate, and a distal end portion of the tab connection portion may be flat.

[0010] When the second end of the electrode assembly is a reference plane, a first height between the inner surface of the cap plate and the second end of the electrode assembly may be greater than a second height between the inner surface of the tab connection portion and the second end of the electrode assembly.

[0011] The inner surface of the tab connection portion facing the second electrode tab may protrude further toward the second end of the electrode assembly than the inner surface of the cap plate.

[0012] When the second end of the electrode assembly is a reference plane, a first height between the inner surface of the cover plate and the second end of the electrode assembly may be greater than a second height between the inner surface of the tab connecting portion facing the second electrode tab and the second end of the electrode assembly.

[0013] The terminal plate may include stainless steel and may be formed by a drawing process.

[0014] The flange portion may be parallel to the cover plate, and the tab connection portion may be recessed inwardly toward the housing and may have a flat inner surface.

[0015] The rechargeable battery may further include an insulating member between the cap plate and the second electrode tab.

[0016] The insulating member may be plate-shaped and may have an opening therein. The opening in the insulating member may correspond to the terminal opening in the cap plate.

[0017] The opening in the insulating member may have a diameter smaller than a diameter of the terminal opening.

[0018] The height of the rechargeable battery is the maximum distance between the outer plane of the shell and the outer plane of the terminal plate when the opening of the shell is closed and sealed by the cover assembly, the diameter of the rechargeable battery is the outer diameter of the shell, and the ratio of the height to the diameter of the rechargeable battery may be less than or equal to 1.

[0019] The first electrode, the second electrode, and the separator may be spirally wound together.

[0020] The inner surface of the tab connection portion may have a curved shape convexly protruding toward the second end of the electrode assembly, and may extend beyond the inner surface of the cap plate toward the second end of the electrode assembly.

[0021] The inner surface of the tab connection portion may have a partially spherical, hemispherical, partially ellipsoidal, or hemispherical shape.

[0022] According to an embodiment of the present invention, because the inner surface of the tab connecting portion has a height difference with the inner surface of the cover plate, a short circuit between the second electrode tab connected to the tab connecting portion of the terminal plate and the cover plate connected to the first electrode tab having a polarity different from that of the second electrode tab can be structurally prevented. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 is a perspective view of a rechargeable battery according to a first exemplary embodiment of the present invention.

[0024] Figure 2 for Figure 1 An exploded perspective view of a rechargeable battery is shown in FIG.

[0025] Figure 3 For along Figure 1 A cross-sectional view taken along line III-III in FIG.

[0026] Figure 4 is an exploded perspective view of a rechargeable battery according to a second exemplary embodiment of the present invention.

[0027] Figure 5 For along Figure 4 A cross-sectional view taken along line VV in FIG. DETAILED DESCRIPTION

[0028] The present invention will be described more fully hereinafter with reference to the accompanying drawings showing exemplary embodiments of the present invention. As will be appreciated by those skilled in the art, the described embodiments may be modified in various ways without departing from the scope of the present invention. Therefore, the accompanying drawings and description should be considered as illustrative rather than restrictive in nature.

[0029] It will be understood that when an element or layer is referred to as being "on," "connected to," or "coupled to" another element or layer, it may be directly on, directly connected to, or directly coupled to another element or layer, or one or more intermediate 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, there are no intermediate elements or layers. For example, when a first element is described as being "coupled to" 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 through one or more intermediate elements.

[0030] In the drawings, for clear illustration, the sizes of various elements, layers, etc. may be exaggerated. The same reference numerals represent the same elements. As used herein, the term "and / or" includes any and all combinations of one or more related listed items. Further, when describing embodiments of the present invention, the use of "may" relates to "one or more embodiments of the present invention". Statements such as "at least one of..." modify the entire column of elements when following a column of elements, rather than modifying the individual elements in the column. In addition, the term "exemplary" is intended to indicate an example or illustration. As used herein, the term "using" may be considered to be synonymous with the term "utilizing". As used herein, the terms "substantially", "approximately" and similar terms are used as approximate terms, rather than as terms of degree, and are intended to illustrate the inherent changes in measurements or calculated values ​​that will be recognized by those skilled in the art.

[0031] It will be understood that although the terms first, second, third, etc. may be 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. Therefore, the 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 exemplary embodiments.

[0032] For ease of description, spatially related terms such as "below", "below", "down", "above", "on", etc. may be used herein to describe the relationship of one element or feature to other elements or features as shown in the figures. It will be understood that spatially related terms are intended to include different orientations in the use or operation of the device in addition to the orientation depicted in the figures. For example, if the device in the figure is flipped, the elements described as being "below" or "below" other elements or features will be oriented as being "above" or "on" other elements or features. Therefore, the term "below" may include both above and below. The device may be oriented otherwise (rotated 90 degrees or in other orientations), and the spatially related descriptors used herein should be interpreted accordingly.

[0033] The terms used herein are for the purpose of describing specific example embodiments of the present invention and are not intended to limit the example embodiments of the present invention. As used herein, the singular form "a" is intended to also include the plural form, unless the context clearly indicates otherwise. It will be further understood that the terms "comprise" and / or "comprising" when used in this specification specify the presence of the features, integers, steps, operations, elements and / or parts, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, parts and / or combinations thereof.

[0034] According to an exemplary embodiment of the present invention, an ultra-small rechargeable battery is provided. The ultra-small rechargeable battery may be a coin cell type battery or a button cell type battery. A coin cell type battery or a button cell type battery is a thin coin or button cell type battery having a height (H) to diameter (D) ratio (H / D) of 1 or less (see, e.g. Figure 1 ).

[0035] Because a coin cell type battery or a button cell type battery is generally cylindrical, its cross section in the horizontal direction is circular. However, the present invention is not limited thereto, and the cross section of the rechargeable battery in the horizontal direction may have an elliptical or polygonal shape. According to an embodiment of the present invention, the diameter (D) is the maximum diameter (e.g., the maximum outer diameter) of the housing of the rechargeable battery in the horizontal direction, and the height (H) is the maximum distance between the outer plane of the housing of the rechargeable battery and the outer plane of the terminal plate.

[0036] However, the coin cell type battery or button cell type battery is an example, and the present invention is not limited thereto. For example, the rechargeable battery may be a cylindrical or pin type battery. Hereinafter, the coin cell type battery or button cell type battery will be described in detail as an example embodiment.

[0037] Figure 1 is a perspective view of a rechargeable battery according to a first exemplary embodiment of the present invention, Figure 2 for Figure 1 An exploded perspective view of a rechargeable battery is shown in FIG. Figure 3 For along Figure 1 A cross-sectional view taken along line III-III in FIG.

[0038] See also Figure 1-Figure 3 , a rechargeable battery 1 according to the first exemplary embodiment includes an electrode assembly 10, a case 20, and a cap assembly 30. The cap assembly 30 includes a cap plate 31 and a terminal plate 32. The cap plate 31 and the terminal plate 32 are heat-sealed (e.g., heat-sealed together) by a heat-sealing member 34 disposed therebetween.

[0039] The heat sealing member 34 is a medium for coupling the cover plate 31 and the terminal plate 32 to each other. For example, the heat sealing member 34 may include (or may be formed of) an electrically insulating material such as a polymer, and may be melted by using, for example, a laser to seal to both the cover plate 31 and the terminal plate 32.

[0040] In the first exemplary embodiment, the terminal plate 32 is coupled to the cap plate 31 through the heat sealing member 34 , so that a stable coupling structure is formed while effectively insulating between the terminal plate 32 and the cap plate 31 without a separate insulating element or configuration.

[0041] The coin cell type battery manufactured as an ultra-small rechargeable battery has design limitations in terms of space, and accordingly, functionality should be ensured while simplifying the structure and manufacturing process. Therefore, in the first exemplary embodiment, insulation and coupling between the terminal plate 32 and the cap plate 31 are provided by the heat sealing member 34.

[0042] The electrode assembly 10 includes a first electrode (e.g., a negative electrode) 11 and a second electrode (e.g., a positive electrode) 12 disposed on opposite sides of a separator 13, which is an electrical insulating member. The electrode assembly 10 is formed by spirally winding the first electrode 11, the separator 13, and the second electrode 12. Therefore, the electrode assembly 10 may be formed in a jelly roll type.

[0043] The electrode assembly 10 is configured for charging and discharging, and the spiral winding axis of the electrode assembly 10 may be parallel to the height direction of the case 20. The first end (e.g., lower end) 101 of the electrode assembly 10 and the second end (e.g., upper end) 102 of the electrode assembly 10 may be flat and may be parallel to each other. In the first exemplary embodiment, the electrode assembly 10 does not have a center pin, but in other embodiments, the center pin may be provided on (or along) the spiral winding axis (e.g., may be provided at the center of the electrode assembly 10).

[0044] The case 20 receives (or houses) the electrode assembly 10 and faces the first end 101 of the opposite ends 101, 102 of the electrode assembly 10. For example, the case 20 has a cylindrical shape and houses the jelly roll type electrode assembly 10, and the cap assembly 30 closes and seals the opening 21 of the cylindrical case 20.

[0045] The electrode assembly 10 further includes a first electrode tab 51 connected to the first electrode 11 and a second electrode tab 52 connected to the second electrode 12. The first electrode 11 and the second electrode 12 are led out through (or to) the first end 101 and the second end 102 of the electrode assembly 10, respectively.

[0046] When the electrode assembly 10 is in the case 20 , the first electrode tab 51 is electrically connected to the bottom of the case 20 , and the second electrode tab 52 is electrically connected to the terminal plate 32 of the cap assembly 30 .

[0047] In addition, the cap plate 31 of the cap assembly 30 is coupled to the case 20 while facing the second end 102 of the opposite ends 101, 102 of the electrode assembly 10, and thus covers and seals the opening 21 of the case 20. In this embodiment, the terminal plate 32 is connected to the second electrode tab 52 while being coupled to the cap plate 31.

[0048] Hereinafter, the first electrode 11 and the second electrode 12 are described as a negative electrode and a positive electrode, respectively, but the present invention is not limited thereto. For example, the first electrode 11 and the second electrode 12 may be a positive electrode and a negative electrode, respectively.

[0049] The first electrode (e.g., negative electrode) 11 has a long strip shape (e.g., strip shape) and includes a current collector (e.g., metal foil, such as copper (Cu) foil), which has a negative electrode coating portion and a negative electrode uncoated region, the negative electrode coating portion is a region where a negative electrode active material layer is applied, and the negative electrode uncoated region is a region where no active material is applied. The negative electrode uncoated region may be located at one end of the negative electrode in the length direction.

[0050] The second electrode (e.g., positive electrode) 12 has a long strip shape (e.g., strip shape) and includes a current collector (e.g., metal foil, such as aluminum (Al) foil) having a positive electrode coating portion and a positive electrode uncoated region, the positive electrode coating portion being a region where a positive electrode active material layer is applied, and the positive electrode uncoated region being a region where no active material is applied. The positive electrode uncoated region may be located at one end of the positive electrode in the length direction.

[0051] The electrode assembly 10 is inserted into the case 20 through an opening (e.g., a circular opening) 21 formed on one side of the case 20, and the case 20 has a space (e.g., has a sufficient space or is sized to be sufficient) to receive (or accommodate) the electrode assembly 10 and the electrolyte solution therein. For example, the case 20 may have a cylindrical shape with a height (H) smaller than a diameter (D).

[0052] The terminal plate 32 of the cap assembly 30 has a flange portion 321 and a tab connection portion 322. The flange portion 321 is coupled (e.g., attached) to the cap plate 31 while being electrically insulated therefrom. The tab connection portion 322 protrudes from the flange portion 321 toward the electrode assembly 10, extends into (e.g., is inserted into) the terminal opening (e.g., terminal hole) 311 in the cap plate 31, and is connected to the second electrode tab 52 of the electrode assembly 10.

[0053] In this embodiment, the inner (or bottom) surface 221 of the tab connection portion 322 has a height difference ΔH with the inner (or bottom) surface 312 of the cap plate 31. Even when the second electrode tab 52 extends (e.g., stretches) with a certain length margin between the second end 102 of the electrode assembly 10 and the inner surface 312 of the cap plate 31, the height difference ΔH provides a relatively large safety margin, which can help prevent a short circuit between the second electrode tab 52 having a positive polarity and the cap plate 31 having a negative polarity.

[0054] For example, the height difference ΔH may structurally prevent (or substantially prevent) mutual short circuit between the second electrode tab 52 having a positive polarity connected to the terminal plate 32 and the cap plate 31 having a negative polarity connected to the first electrode tab 51 .

[0055] For example, the inner surface 221 of the tab connection portion 322 protrudes farther toward the second end 102 of the electrode assembly 10 than the inner surface 312 of the cap plate 31, and is formed to be flat (for example, the inner surface 221 of the tab connection portion 322 is closer to the second end 102 of the electrode assembly 10 than the inner surface 312 of the cap plate 31). In one example, the distal portion of the tab connection portion 322 may be flat. When the second end 102 of the electrode assembly 10 is a reference plane, a first height H1 is formed between the inner surface 312 of the cap plate 31 and the second end 102 of the electrode assembly 10.

[0056] A second height H2 is formed between the flat inner surface 221 of the tab connection portion 322 and the second end 102 of the electrode assembly 10. Since the second end 102 of the electrode assembly 10 is a reference plane, the second height H2 is smaller than the first height H1. That is, the height difference ΔH between the first height H1 and the second height H2 can structurally prevent the second electrode tab 52 and the cap plate 31 from being short-circuited to each other.

[0057] The insulating member 61 is disposed between the cap plate 31 and the second electrode tab 52. In the first exemplary embodiment, the insulating member 61 has a plate shape corresponding to the cap plate 31 and may be disposed at least (or only) between the cap plate 31 and the second electrode tab 52.

[0058] The insulating member 61 has an opening (e.g., a through hole) 611 corresponding to (e.g., aligned with or concentric with) the terminal opening 311. The opening 611 in the insulating member 61 may have a smaller diameter than the concentric terminal opening 311 in the cap plate 31. Therefore, the second electrode tab 52 may be further prevented from being short-circuited with the cover member 31 through the terminal opening 311 by the insulating member 61.

[0059] For example, the terminal plate 32 may include stainless steel (or may be formed of stainless steel) and may be formed by a drawing process, for example, by using a plate having a thickness. The terminal plate 32 has a flange portion 321 parallel to the cap plate 31 and a tab connection portion 322 that is recessed from the outside of the housing 20 toward the inside of the housing 20 and has a flat inner surface 221. The flat inner surface 221 provides improved weldability with the second electrode tab 52.

[0060] In the first exemplary embodiment, the entire inner surface 221 of the tab connection portion 322 including a portion facing the second electrode tab 52 is formed within one plane.

[0061] In the rechargeable battery 1 according to the first exemplary embodiment, the height H is the maximum distance between the outer plane of the case 20 and the outer plane of the terminal plate 32 when the opening 21 of the case 20 is closed and sealed by the cap assembly 30, and the diameter D is the outer diameter of the case 20. In this embodiment, the ratio (H / D) of the height H to the diameter D is less than or equal to about 1 (H / D≤1). For example, the rechargeable battery 1 is a coin cell type battery or a button cell type battery that can be formed in the shape of a thin coin or button.

[0062] Hereinafter, a second exemplary embodiment of the present invention will be described. Components in the second exemplary embodiment that are identical or substantially similar to those in the first exemplary embodiment may not be described again. Instead, the description of the second exemplary embodiment may focus on the different components therebetween.

[0063] Figure 4 is an exploded perspective view of a rechargeable battery according to a second exemplary embodiment of the present invention, Figure 5 For along Figure 4 A cross-sectional view taken along line VV in FIG. Figure 4 and Figure 5 , the rechargeable battery 2 according to the second exemplary embodiment includes a terminal plate 33 having a flange portion 331 and a tab connection portion 332 .

[0064] The flange portion 331 is formed parallel to the cap plate 31 and is coupled (e.g., attached) to the cap plate 31 while being electrically insulated therefrom. The tab connection portion 332 protrudes convexly from the flange portion 331 toward the electrode assembly 10, extends into the terminal opening 311, and is connected to the second electrode tab 52 of the electrode assembly 10.

[0065] In one example, the inner surface 323 of the tab connection portion 332 may have a curved surface shape that protrudes convexly toward the second end 102 of the electrode assembly 10. The tab connection portion 332 protrudes into the interior of the housing 20, and the inner surface 323 of the tab connection portion 332 has a partially spherical, hemispherical, partially ellipsoidal, or semi-ellipsoidal shape. For example, the tab connection portion 332 may be a curved portion of a partially spherical cylinder, a curved portion of a hemispherical cylinder, a curved portion of a partially ellipsoidal cylinder, or a curved portion of a semi-ellipsoidal cylinder, and is connected to the flange portion 331.

[0066] In this embodiment, the inner surface 323 of the tab connection portion 332 has a height difference ΔH with the inner surface 312 of the cap plate 31. Even when the second electrode tab 52 extends with a certain length margin between the second end 102 of the electrode assembly 10 and the inner surface 312 of the cap plate 31, the height difference ΔH provides a relatively large safety margin, which can prevent (or substantially prevent) a short circuit between the second electrode tab 52 and the inner surface 312 of the cap plate 31.

[0067] For example, the height difference ΔH may structurally prevent the second electrode tab 52 connected to the terminal plate 32 and having a positive polarity and the cap plate 31 connected to the first electrode tab 51 and having a negative polarity from being short-circuited with each other.

[0068] While the invention has been described in connection with what are presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments. The present disclosure is intended to cover various modifications and equivalent arrangements included within the scope of the appended claims.

[0069] Notes on some references

[0070] 1: Rechargeable battery 10: Electrode assembly

[0071] 11: First electrode

[0072] 12: Second electrode

[0073] 13: partition 20: shell

[0074] 21: Opening 30: Cover assembly

[0075] 31: Cover plate 32, 33: Terminal plate

[0076] 51: first electrode terminal tab 52: second electrode terminal tab

[0077] 61: Insulating member 101: First end

[0078] 102: second end 221, 323: inner surface

[0079] 311: Terminal opening 312: Inner surface

[0080] 321, 331: Flange part 322, 332: Lug connection part

[0081] 611: Opening D: Diameter

[0082] H: Height H1: First height

[0083] H2: Second height ΔH: Height difference

Claims

1. A rechargeable battery comprising: an electrode assembly comprising a first electrode, a second electrode, a separator between the first electrode and the second electrode, a first electrode tab connected to the first electrode, and a second electrode tab connected to the second electrode, the electrode assembly having opposite first and second ends; a housing accommodating the electrode assembly and facing the first end of the electrode assembly, the first electrode tab being connected to the housing; A cover assembly is used to close and seal the opening of the housing, and the cover assembly includes: a cover plate coupled to the case, covering the opening and facing the second end of the electrode assembly; and a terminal plate coupled to the cover plate; and an insulating member, between the cap plate and the second electrode terminal tab, The terminal board comprises: a flange portion coupled to the cover plate and electrically insulated from the cover plate; and a tab connecting portion protruding from the flange portion toward the electrode assembly, extending into the terminal opening in the cap plate and connected to the second electrode tab; and wherein an inner surface of the tab connection portion has a height difference with an inner surface of the cap plate, and the inner surface of the tab connection portion protrudes further toward the second end of the electrode assembly than a surface of the insulating member facing the second electrode tab, and wherein each of the tab connection portion and the second electrode tab is spaced apart from the insulating member. 2 . The rechargeable battery according to claim 1 , wherein a distal end portion of the tab connection portion is flat. 3 . The rechargeable battery of claim 1 , wherein the insulating member is located on the inner surface of the cap plate. 4 . The rechargeable battery of claim 1 , wherein a portion of the insulating member is located between the cap plate and the second electrode tab.

5. The rechargeable battery according to claim 1, wherein When the second end of the electrode assembly is a reference plane, a first height between the inner surface of the cover plate and the second end of the electrode assembly is greater than a second height between the inner surface of the tab connecting portion facing the second electrode tab and the second end of the electrode assembly. 6 . The rechargeable battery of claim 1 , wherein the terminal plate comprises stainless steel and is formed by a drawing process.

7. The rechargeable battery according to claim 1, wherein the flange portion is parallel to the cap plate, and The lug connection portion is recessed inwardly toward the housing and has a flat inner surface.

8. The rechargeable battery according to claim 1, wherein the insulating member is plate-shaped and has an opening therein, and wherein the opening in the insulating member corresponds to the terminal opening in the cap plate. 9 . The rechargeable battery according to claim 8 , wherein the opening in the insulating member has a diameter smaller than a diameter of the terminal opening.

10. The rechargeable battery according to claim 1, wherein the height of the rechargeable battery is a maximum distance between an outer plane of the case and an outer plane of the terminal plate when the opening of the case is closed and sealed by the cap assembly, wherein the diameter of the rechargeable battery is the outer diameter of the housing, and The ratio of the height to the diameter of the rechargeable battery is less than or equal to 1. 11 . The rechargeable battery of claim 1 , wherein the first electrode, the second electrode, and the separator are spirally wound together. 12 . The rechargeable battery of claim 1 , wherein the inner surface of the tab connection portion has a curved shape convexly protruding toward the second end of the electrode assembly and extends beyond the inner surface of the cap plate toward the second end of the electrode assembly. 13 . The rechargeable battery of claim 12 , wherein the inner surface of the tab connection portion has a partially spherical shape. 14 . The rechargeable battery of claim 12 , wherein the inner surface of the tab connection portion has a hemispherical shape. 15 . The rechargeable battery of claim 12 , wherein the inner surface of the tab connection portion has a partial ellipsoidal shape. 16 . The rechargeable battery of claim 12 , wherein the inner surface of the tab connection portion has a semi-ellipsoidal shape.

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