Rechargeable battery

Abstract

A rechargeable battery includes: an electrode assembly including a first electrode, a second electrode and a separator between the first electrode and the second electrode; a shell connected to the first electrode and accommodating the electrode assembly, and including an opening to receive the electrode assembly; a cover plate coupled to the shell to cover a peripheral area of ​​the opening and including a through hole to expose a central area of ​​the opening; and a terminal plate coupled to and insulated from the cover plate to cover the through hole and connected to the second electrode, wherein an outer surface of the shell has a first concave-convex shape.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to and the benefit of Korean Patent Application No. 10-2020-0078578 filed in the Korean Intellectual Property Office on June 26, 2020, the entire contents of which are incorporated herein by reference. Technical Field

[0003] Aspects of embodiments of the present disclosure relate to rechargeable batteries. Background Art

[0004] Generally speaking, a rechargeable battery is a battery that can be repeatedly charged and discharged.

[0005] In recent years, as the demand for wearable devices such as headphones, in-ear headphones, smart watches, and body-attached medical devices using wireless communication such as Bluetooth increases, the demand for ultra-small rechargeable batteries installed in wearable devices is increasing.

[0006] The electrode terminals arranged on the outer surface of the ultra-small rechargeable battery are in contact with the contact terminals of the wearable device to supply power to the wearable device. Since an oxide film is naturally formed on the surface of the electrode terminals of the ultra-small rechargeable battery, there is a problem of increased contact resistance between the electrode terminals of the ultra-small rechargeable battery and the contact terminals of the wearable device.

[0007] The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art. Summary of the invention

[0008] According to an aspect of one or more embodiments, a rechargeable battery is provided in which an increase in contact resistance between the rechargeable battery and a contact terminal of a device is suppressed even if an oxide layer is formed on an outer surface of the rechargeable battery.

[0009] According to one or more embodiments, a rechargeable battery includes: an electrode assembly including a first electrode, a second electrode and a separator between the first electrode and the second electrode; a shell connected to the first electrode and accommodating the electrode assembly, and including an opening to receive the electrode assembly; a cover plate coupled to the shell to cover a peripheral area of ​​the opening and including a through hole to expose a central area of ​​the opening; and a terminal plate coupled to and insulated from the cover plate to cover the through hole and connected to the second electrode, wherein an outer surface of the shell has a first concave-convex shape.

[0010] The outer surface of the housing may contact an external first contact terminal.

[0011] An oxide layer may be between the concave portion of the first concavo-convex shape and the first contact terminal, and the oxide layer may not be between the convex portion of the first concavo-convex shape and the first contact terminal.

[0012] The first concavo-convex shape may be formed by etching using a laser beam.

[0013] The first concavo-convex shape may include at least one of a comb-teeth shape, a chessboard shape, a circular shape, and an elliptical shape on a plane.

[0014] The outer surface of the cover plate may have a second concavo-convex shape.

[0015] The outer surface of the cap plate may contact an external second contact terminal.

[0016] An oxide layer may be between the concave portion of the second concavo-convex shape and the second contact terminal, and the oxide layer may not be between the convex portion of the second concavo-convex shape and the second contact terminal.

[0017] The terminal plate may include: a terminal portion disposed on the cap plate; and a protrusion portion protruding from the terminal portion to pass through the through hole and connected to the second electrode.

[0018] The rechargeable battery may further include a sealing portion between the terminal portion and the cap plate and coupling the cap plate and the terminal portion.

[0019] An outer surface of the terminal portion may have a third concavo-convex shape.

[0020] The outer surface of the terminal portion may contact an external third contact terminal.

[0021] An oxide layer may be between the concave portion of the third concavo-convex shape and the third contact terminal, and the oxide layer may not be between the convex portion of the third concavo-convex shape and the third contact terminal.

[0022] The case and the cap plate may have the same polarity as that of the first electrode, and the terminal plate may have the same polarity as that of the second electrode.

[0023] The electrode assembly may further include: a first electrode tab extending from the first electrode and coupled to the case; and a second electrode tab extending from the second electrode and coupled to the terminal plate.

[0024] According to an exemplary embodiment, a rechargeable battery is provided which suppresses an increase in contact resistance between the rechargeable battery and a contact terminal of a device even if an oxide layer is formed on an outer surface of the rechargeable battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 is a perspective view showing a rechargeable battery according to an embodiment.

[0026] Figure 2 For along Figure 1 A cross-sectional view taken along line II-II in FIG.

[0027] Figure 3 is a cross-sectional view showing a first contact terminal making contact with an outer surface of a case of a rechargeable battery according to an embodiment.

[0028] Figure 4 is a cross-sectional view of a rechargeable battery according to another embodiment.

[0029] Figure 5 is a cross-sectional view of a rechargeable battery according to another embodiment.

[0030] Description of Reference Numerals

[0031] 100: Electrode assembly 200: Shell

[0032] 300: Cover plate 400: Terminal plate

[0033] PD1: First concave-convex shape DETAILED DESCRIPTION

[0034] The present invention will be more fully described herein with reference to the accompanying drawings, in which some example embodiments of the present invention are shown. As will be appreciated by those skilled in the art, the described embodiments may be modified in a variety of ways without departing from the spirit or scope of the present invention. The accompanying drawings and descriptions are to be regarded as illustrative and non-restrictive in nature. Similar reference numerals refer to similar elements throughout the specification.

[0035] In addition, unless explicitly described to the contrary, it should be understood that terms such as "include", "comprises" or "has" used in this specification indicate the existence of the features, numbers, steps, operations, components, parts and / or their combinations, but do not preclude the existence or addition of one or more other features, numbers, steps, operations, components, parts or their combinations.

[0036] Further, in the present specification, it should be understood that when a component is referred to as being “connected” or “coupled” to another component, it may be directly connected or coupled to the other component or connected or coupled to the other component with one or more other components interposed therebetween.

[0037] Unless the context clearly indicates otherwise, singular forms shall include plural forms.

[0038] It should be understood that although the terms "first", "second", etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are used to distinguish one element from another element. For example, a first element may be referred to as a "second" element, and similarly, a second element may be referred to as a "first" element without departing from the scope of the exemplary embodiments of the present invention. Unless the context clearly indicates otherwise, a term in the singular may include a plural form.

[0039] In addition, terms such as "below", "lower", "above", "upper", etc. are used to describe the relationship of the configurations shown in the drawings. However, these terms are used as relative concepts and are described with reference to the directions indicated in the drawings.

[0040] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as those commonly understood by those of ordinary skill in the art to which the inventive concept belongs. It should also be understood that terms defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant art, and should not be interpreted in an ideal or overly formal sense unless explicitly defined in this article.

[0041] Next, refer to Figures 1 to 3 A rechargeable battery according to an embodiment is described.

[0042] The rechargeable battery according to an embodiment is an ultra-small rechargeable battery, and may be a coin-type battery or a button-type battery, but is not limited thereto, and in another embodiment, may be a cylindrical or pin-type battery.

[0043] Here, a coin cell or button cell is a thin coin cell or button cell, and may refer to a battery having a height-to-diameter ratio of 1 or less, but is not limited thereto. In one embodiment, the coin cell or button cell is cylindrical, and the horizontal cross section is circular, but the present invention is not limited thereto, and in another embodiment, the horizontal cross section may be elliptical or polygonal. At this time, the diameter may refer to the maximum distance based on the horizontal direction of the battery, and the height may refer to the maximum distance based on the vertical direction of the battery (the distance from the flat bottom surface to the flat uppermost surface).

[0044] Herein, a coin type battery or a button type battery which is a rechargeable battery that can be repeatedly charged and discharged is described as an example, but, as another example, a coin type battery or a button type battery which can only be discharged may also be included in the present invention.

[0045] Figure 1 is a perspective view showing a rechargeable battery according to an embodiment; and Figure 2 For along Figure 1 A cross-sectional view taken along line II-II in FIG.

[0046] See also Figure 1 and Figure 2 , a rechargeable battery 1000 according to an embodiment includes an electrode assembly 100 , a case 200 , a cap plate 300 , a terminal plate 400 , and a sealing part 500 .

[0047] The electrode assembly 100 is accommodated in the case 200. The lower portion of the electrode assembly 100 faces the lower portion of the case 200, and the upper portion of the electrode assembly 100 faces the cap plate 300 and the terminal plate 400 covering the opening 210 of the case 200. In one embodiment, the upper and lower portions of the electrode assembly 100 may have a planar shape such that they are parallel to each other, but are not limited thereto.

[0048] The electrode assembly 100 includes a first electrode 110 , a second electrode 120 , a separator 130 , a first electrode tab 140 , and a second electrode tab 150 .

[0049] The first electrode 100 and the second electrode 120 are separated from each other, and a separator 130 including an insulating material is disposed between the first electrode 110 and the second electrode 120. In one embodiment, the first electrode 110 may be an anode and the second electrode 120 may be a cathode, but the present invention is not limited thereto, and in another embodiment, the first electrode 110 may be a cathode and the second electrode 120 may be an anode.

[0050] In one embodiment, the first electrode 110 has a strip shape extending in one direction and includes: an anode coating region, which is a region where an anode active material layer is coated on a current collector of a metal foil (e.g., a copper foil); and an anode uncoated region, which is a region where an active material is not coated. The anode uncoated region may be disposed at an end portion of the first electrode 110 in the extending direction.

[0051] In one embodiment, the second electrode 120 has a strip shape, which is spaced apart from the first electrode 110 with the separator 130 interposed therebetween, and the second electrode 120 extends in one direction and includes: a cathode coating region, which is a region where the cathode active material layer is coated on a current collector of a metal foil (e.g., an aluminum foil); and a cathode uncoated region, which is a region where the active material is not coated. The cathode uncoated region may be provided at an end portion of the second electrode 120 in the extending direction.

[0052] The separator 130 extends in a direction between the first electrode 110 and the second electrode 120 to prevent or substantially prevent a short circuit between the first electrode 110 and the second electrode 120 .

[0053] In one embodiment, the first electrode 110, the separator 130, and the second electrode 120 are sequentially stacked and wound into a jelly roll shape, but are not limited thereto and may be formed into any of various known shapes. Each of the first electrode 110, the second electrode 120, and the separator 130 may include any of various known materials.

[0054] The first electrode tab 140 extends from the first electrode 110 of the electrode assembly 100 to the case 200. The first electrode tab 140 is combined (or coupled) with a lower portion of the case 200 to connect the first electrode 110 and the case 200. The first electrode tab 140 contacts the first electrode 110 and the case 200. Due to the first electrode tab 140, the case 200 has the same polarity (e.g., anode polarity) as the first electrode 110.

[0055] The second electrode tab 150 extends from the second electrode 120 of the electrode assembly 100 to the terminal plate 400. In one embodiment, the second electrode tab 150 is combined (or coupled) with the protrusion 420 of the terminal plate 400 to connect the second electrode 120 and the terminal plate 400. The second electrode tab 150 contacts the second electrode 120 and the terminal plate 400. Due to the second electrode tab 150, the terminal plate 400 has the same polarity (e.g., cathode polarity) as the second electrode 120.

[0056] In one embodiment, a center pin passing through the center of the electrode assembly 100 in a vertical direction is provided at a central portion of the electrode assembly 100 , and the center pin may support the first and second electrode tabs 140 and 150 , but is not limited thereto.

[0057] The housing 200 is connected to the first electrode 110 of the electrode assembly 100 and accommodates the electrode assembly 100. The housing 200 includes an opening 210 configured to receive the electrode assembly 100 and expose the upper portion of the electrode assembly 100. The lower portion of the housing 200 is connected to the first electrode 110 of the electrode assembly 100 through the first electrode tab 140 and has the same polarity (e.g., anode polarity) as the first electrode 110. In one embodiment, the housing 200 has a cylindrical shape for accommodating the electrode assembly 100 in a jelly roll form, but is not limited thereto and may have any of various known shapes. The housing 200 may accommodate any of various known electrolyte solutions together with the electrode assembly 100.

[0058] The first outer surface 201 of the housing 200 disposed on the lower side of the housing 200 has a first concavoconvex shape PD1. The first concavoconvex shape PD1 includes a plurality of first convex portions P1 and a plurality of first concave portions D1. The first concave portions D1 of the plurality of first concave portions D1 are respectively disposed between the first convex portions P1 of the plurality of first convex portions P1, and the first convex portions P1 of the plurality of first convex portions P1 are respectively disposed between the first concave portions D1 of the plurality of first concave portions D1. The plurality of first concave portions D1 and the plurality of first convex portions P1 define the first concavoconvex shape PD1 of the first outer surface 201. The first concavoconvex shape PD1 may include at least one of a comb shape, a chessboard shape, a circular shape, an elliptical shape, and a polygonal shape on a plane, but is not limited thereto. In one embodiment, the first concave portion D1 and the first convex portion P1 have a rectangular or square cross-sectional shape, but are not limited thereto, and may have any cross-sectional shape among various cross-sectional shapes, such as any of a triangular shape, a polygonal shape, a circular shape, an elliptical shape, and an irregular shape.

[0059] In an embodiment, in the first outer surface 201 of the housing 200 , any of various recognition patterns such as letters, symbols, and numbers may be formed in a plane area, and the recognition patterns may have a recessed or protruding shape.

[0060] In an embodiment, the first concavo-convex shape PD1 may be formed by etching the first outer surface 201 of the housing 200 using a laser beam, but is not limited thereto.

[0061] As another example, the first concavo-convex shape PD1 may be formed by surface-treating the first outer surface 201 of the housing 200 using a known MEMS process including photolithography, but is not limited thereto.

[0062] In one embodiment, the first outer surface 201 of the housing 200 may be an anode terminal of the rechargeable battery 1000, and a contact terminal of a device such as a wearable device may contact the first outer surface 201 of the housing 200. In one embodiment, an outer surface of the terminal plate 400 may be a cathode terminal of the rechargeable battery 1000, and another contact terminal of the device may contact the outer surface of the terminal plate 400.

[0063] In one embodiment, the oxide layer OL may be formed on the first outer surface 201 of the housing 200 due to natural oxidation, but is not limited thereto.

[0064] In an embodiment, the housing 200 includes stainless steel, but is not limited thereto, and may include a metal such as any one of aluminum, nickel, and copper.

[0065] The opening 210 of the housing 200 is covered by the cap plate 300 and the terminal plate 400 .

[0066] The cover plate 300 is combined with the housing 200 to cover the peripheral area of ​​the opening 210. The cover plate 300 includes a through hole 310 exposing the central area of ​​the opening 210. In one embodiment, the cover plate 300 covers the peripheral area of ​​the opening 210 by directly coupling to the side wall of the housing 200 forming the opening 210 of the housing 200 by a welding process. In one embodiment, the cover plate 300 has a ring shape due to the through hole 310 formed in the center, but is not limited thereto. The cover plate 300 is combined with the housing 200 and has the same polarity (e.g., anode polarity) as the first electrode 110.

[0067] In an embodiment, the cover plate 300 includes stainless steel, but is not limited thereto, and may include a metal such as any one of aluminum, nickel, and copper.

[0068] The terminal plate 400 is insulated from the cap plate 300 and combined to the cap plate 300 to cover the through hole 310 of the cap plate 300. In one embodiment, the terminal plate 400 is disposed on the cap plate 300, but is not limited thereto, and may be disposed between the cap plate 300 and the electrode assembly 100. The terminal plate 400 covers the central area of ​​the opening 210 of the housing 200 exposed by the through hole 310 of the cap plate 300. In one embodiment, since the terminal plate 400 covers the central area of ​​the opening 210 and the cap plate 300 covers the peripheral area of ​​the opening 210, the opening 210 of the housing 200 is completely covered by the terminal plate 400 and the cap plate 300. The terminal plate 400 is connected to the second electrode tab 150 of the electrode assembly 100 to connect to the second electrode 120 of the electrode assembly 100. The terminal plate 400 has the same polarity (e.g., cathode polarity) as the second electrode 120.

[0069] The terminal plate 400 includes a terminal portion 410 and a protrusion portion 420 .

[0070] The terminal portion 410 is disposed or arranged on the cap plate 300 and overlaps the cap plate 300. The terminal portion 410 has a larger area than the protrusion 420. For example, the terminal portion 410 may have a larger diameter than the protrusion 420. The lower surface of the terminal portion 410 contacts the sealing portion 500, and the terminal portion 410 is insulated from the cap plate 300 and coupled to the cap plate 300 by the sealing portion 500.

[0071] The protrusion 420 protrudes from the terminal part 410 corresponding to the through hole 310 of the cap plate 300 and passes through the through hole 310. The lower surface of the protrusion 420 contacts the second electrode tab 150. Since the protrusion 420 is combined with the second electrode tab 150, the terminal plate 400 has the same polarity as the second electrode 120.

[0072] In an embodiment, the terminal plate 400 includes stainless steel, but is not limited thereto, and may include a metal such as any one of stainless steel, nickel, and copper.

[0073] The sealing portion 500 is disposed between the cover plate 300 and the terminal portion 410 of the terminal plate 400, and the cover plate 300 and the terminal plate 400 are insulated and combined. The sealing portion 500 includes an insulating material and insulates the cover plate 300 and the terminal plate 400. In one embodiment, the sealing portion 500 is heat-fused between the terminal portion 410 of the cover plate 300 and the terminal plate 400 by using heat or a laser beam, or can be inserted between the terminal portion 410 of the cover plate 300 and the terminal plate 400, however, it is not limited thereto. The sealing portion 500 may include any material among various known materials for insulating and combining the cover plate 300 and the terminal plate 400. Since the sealing portion 500 is combined between the cover plate 300 and the terminal plate 400, the opening 210 of the housing 200 is completely sealed by the cover plate 300, the terminal plate 400 and the sealing portion 500.

[0074] Figure 3 is a cross-sectional view showing a first contact terminal making contact with an outer surface of a case of a rechargeable battery according to an embodiment.

[0075] See also Figure 3 , the first contact terminal CP1, which may be the outside of one contact terminal of the device, contacts the first outer surface 201 of the case 200, which may be the anode terminal of the rechargeable battery 1000. In an embodiment, the other contact terminal of the device may contact the outer surface of the terminal plate 400, which may be the cathode terminal of the rechargeable battery 1000. The first contact terminal CP1 may have a plate or pin shape, but is not limited thereto, and may have any of various known shapes.

[0076] Due to the first concavo-convex shape PD1 in the first outer surface 201 of the housing 200, the plurality of first convex portions P1 included in the first concavo-convex shape PD1 are in contact with the first contact terminal CP1, so that the contact area between the first outer surface 201 of the housing 200 and the first contact terminal CP1 is reduced, thereby increasing the pressure between the first outer surface 201 of the housing 200 and the first contact terminal CP1. Due to the increase in pressure between the first outer surface 201 of the housing 200 and the first contact terminal CP1, the oxide layer OL formed on the first outer surface 201 may be destroyed by the pressure between the first outer surface 201 and the first contact terminal CP1 and separated from the first outer surface 201, and the first convex portion P1 of the first outer surface 201 may be in direct contact with the first contact terminal CP1.

[0077] In one embodiment, the oxide layer OL is between the first concave portion D1 of the first concavo-convex shape PD1 and the first contact terminal CP1, and the oxide layer OL is pressure-damaged between the first convex portion P1 of the first concavo-convex shape PD1 and the first contact terminal CP1 and is not therebetween.

[0078] That is, even if an oxide layer OL is formed on the first outer surface 201 of the shell 200 of the rechargeable battery 1000, as the contact area between the first outer surface 201 and the first contact terminal CP1 is reduced due to the first concave-convex shape PD1 and the pressure between the first outer surface 201 and the first contact terminal CP1 increases, since the oxide layer OL on the surface of the first convex portion P1 of the first concave-convex shape PD1 formed on the first outer surface 201 is destroyed by the pressure and the first convex portion P1 of the first outer surface 201 can be in direct contact with the first contact terminal CP1, the increase in contact resistance between the first outer surface 201 of the shell 200, which can be the anode terminal of the rechargeable battery 1000, and the first contact terminal CP1 of the device can be suppressed.

[0079] In addition, even if the contact probe contacts the first outer surface 201 of the shell 200 for testing the rechargeable battery 1000, as the contact area between the first outer surface 201 and the contact probe is reduced due to the first concave-convex shape PD1 and the pressure between the first outer surface 201 and the contact probe is increased, since the oxide layer OL on the surface of the first convex portion P1 of the first concave-convex shape PD1 formed on the first outer surface 201 is destroyed by the pressure and the first convex portion P1 of the first outer surface 201 is in direct contact with the contact probe, the increase in contact resistance between the first outer surface 201 of the shell 200, which can be the anode terminal of the rechargeable battery 1002, and the contact probe is suppressed, thereby improving the reliability of the test of the rechargeable battery 1000.

[0080] That is, even if the oxide layer OL is formed on the first outer surface 201 of the shell 200 which is the outer surface of the rechargeable battery 1000, a rechargeable battery 1000 is provided as follows: in the rechargeable battery 1000, an increase in the contact resistance between the rechargeable battery 1000 and the first contact terminal CP1 of the device is suppressed, and an increase in the contact resistance between the rechargeable battery 1000 and a contact probe for testing the rechargeable battery 1000 is suppressed.

[0081] Next, refer to Figure 4 A rechargeable battery according to another embodiment is described.

[0082] Here, portions different from those of the rechargeable battery according to an embodiment described above are mainly described.

[0083] Figure 4is a cross-sectional view showing a rechargeable battery according to another embodiment.

[0084] See also Figure 4 , a rechargeable battery 1002 according to another embodiment includes an electrode assembly 100 , a case 200 , a cap plate 300 , a terminal plate 400 , and a sealing part 500 .

[0085] The second outer surface 301 of the cover plate 300 disposed on the upper side of the cover plate 300 has a second concavoconvex shape PD2. The second concavoconvex shape PD2 includes a plurality of second convex portions P2 and a plurality of second concave portions D2. The second concave portions D2 in the plurality of second concave portions D2 are respectively disposed between the second convex portions P2 in the plurality of second convex portions P2, and the second convex portions P2 in the plurality of second convex portions P2 are respectively disposed between the second concave portions D2 in the plurality of second concave portions D2. The plurality of second concave portions D2 and the plurality of second convex portions P2 define the second concavoconvex shape PD2 of the second outer surface 301. The second concavoconvex shape PD2 may include at least one of a comb shape, a chessboard shape, a circular shape, an elliptical shape, and a polygonal shape on a plane, but is not limited thereto. The second concave portion D2 and the second convex portion P2 may have a rectangular or square cross-section, but are not limited thereto, and may have any cross-sectional shape among various cross-sectional shapes, such as any shape in a triangular shape, a polygonal shape, a circular shape, an elliptical shape, and an irregular shape.

[0086] In an embodiment, on the second outer surface 301 of the cover plate 300 , any of various recognition patterns such as letters, symbols, and numbers may be formed in a plane area, and the recognition patterns may have a concave or convex shape.

[0087] In an embodiment, the second concavo-convex shape PD2 may be formed by etching the second outer surface 301 of the cover plate 300 using a laser beam, but is not limited thereto.

[0088] In one embodiment, the oxide layer OL may be formed on the second outer surface 301 of the cover plate 300 due to natural oxidation, but is not limited thereto.

[0089] The second contact terminal CP2, which may be the outside of one contact terminal of the device, contacts the second outer surface 301 of the cap plate 300, which may be the anode terminal of the rechargeable battery 1002. In one embodiment, the other contact terminal of the device may contact the outer surface of the terminal plate 400, which may be the cathode terminal of the rechargeable battery 1002.

[0090] Due to the second concavo-convex shape PD2 in the second outer surface 301 of the cover plate 300, the plurality of second convex portions P2 included in the second concavo-convex shape PD2 are in contact with the second contact terminal CP2, the contact area between the second outer surface 301 of the cover plate 300 and the second contact terminal CP2 is reduced, and the pressure between the second outer surface 301 and the second contact terminal CP2 of the cover plate 300 is increased. Due to the increase in pressure between the second outer surface 301 of the cover plate 300 and the second contact terminal CP2, the oxide layer OL formed on the second outer surface 301 may be destroyed by the pressure between the second outer surface 301 and the second contact terminal CP2, and may be separated from the second outer surface 301, so that the second convex portion P2 of the second outer surface 301 is in direct contact with the second contact terminal CP2.

[0091] In one embodiment, the oxide layer OL is between the second concave portion D2 of the second concavo-convex shape PD2 and the second contact terminal CP2, and the oxide layer OL is pressure-damaged between the second convex portion P2 of the second concavo-convex shape PD2 and the second contact terminal CP2 and is not therebetween.

[0092] That is, even if the oxide layer OL is formed on the second outer surface 301 of the cover plate 300 of the rechargeable battery 1002, as the contact area between the second outer surface 301 and the second contact terminal CP2 is reduced by the second concave-convex shape PD2 and the pressure between the second outer surface 301 and the second contact terminal CP2 increases, since the oxide layer OL on the surface of the second convex portion P2 of the second concave-convex shape PD2 formed on the second outer surface 301 is destroyed by the pressure and the second convex portion P2 of the second outer surface 301 is in direct contact with the second contact terminal CP2, the increase in contact resistance between the second outer surface 301 of the cover plate 300, which can be the anode terminal of the rechargeable battery 1002, and the second contact terminal CP2 of the device is suppressed.

[0093] In addition, even if the contact probe contacts the second outer surface 301 of the cover plate 300 for testing the rechargeable battery 1002, as the contact area between the second outer surface 301 and the contact probe is reduced due to the second concave-convex shape PD2 and the pressure between the second outer surface 301 and the contact probe is increased, since the oxide layer OL formed on the surface of the second convex portion P2 of the second concave-convex shape PD2 of the second outer surface 301 is destroyed by the pressure and the second convex portion P2 of the second outer surface 301 is in direct contact with the contact probe, the increase in contact resistance between the second outer surface 301 of the cover plate 300, which can be the anode terminal of the rechargeable battery 1002, and the contact probe is suppressed, thereby improving the reliability of the test of the rechargeable battery 1002.

[0094] That is, even if the oxide layer OL is formed on the second outer surface 301 of the cover plate 300 which is the outer surface of the rechargeable battery 1002, a rechargeable battery 1002 is provided in which an increase in the contact resistance between the rechargeable battery 1002 and the second contact terminal CP2 of the device is suppressed, and an increase in the contact resistance between the rechargeable battery 1002 and a contact probe for testing the rechargeable battery 1002 is suppressed.

[0095] In addition, as the second outer surface 301 of the cap plate 300 of the rechargeable battery 1002 includes the second concavo-convex shape PD2, since the coupling area between the second outer surface 301 of the cap plate 300 and the sealing part 500 increases, the coupling force between the terminal plate 400 and the cap plate 300 through the sealing part 500 is improved.

[0096] Next, refer to Figure 5 A rechargeable battery according to another embodiment is described.

[0097] Here, portions different from those of the rechargeable battery according to an embodiment described above are mainly described.

[0098] Figure 5 is a cross-sectional view showing a rechargeable battery according to another embodiment.

[0099] See also Figure 5 , a rechargeable battery 1003 according to another embodiment includes an electrode assembly 100 , a case 200 , a cap plate 300 , a terminal plate 400 , and a sealing part 500 .

[0100] The third outer surface 401 of the terminal portion 410 of the terminal plate 400 disposed on the upper side of the terminal portion 410 of the terminal plate 400 has a third concavoconvex shape PD3. The third concavoconvex shape PD3 includes a plurality of third convex portions P3 and a plurality of third concave portions D3. The third concave portions D3 of the plurality of third concave portions D3 are respectively disposed between the third convex portions P3 of the plurality of third convex portions P3, and the third convex portions P3 of the plurality of third convex portions P3 are respectively disposed between the third concave portions D3 of the plurality of third concave portions D3. The plurality of third concave portions D3 and the plurality of third convex portions P3 define the third concavoconvex shape PD3 of the third outer surface 401. The third concavoconvex shape PD3 may include at least one of a comb shape, a chessboard shape, a circular shape, an elliptical shape, and a polygonal shape on a plane, but is not limited thereto. In one embodiment, the third concave portion D3 and the third convex portion P3 have a rectangular or square cross-section, but are not limited thereto, and may have any cross-sectional shape among various cross-sectional shapes, such as any shape of a triangular shape, a polygonal shape, a circular shape, an elliptical shape, and an irregular shape.

[0101] In an embodiment, the third concavo-convex shape PD3 may be formed by etching the third outer surface 401 of the terminal part 410 of the terminal plate 400 using a laser beam, but is not limited thereto.

[0102] In one embodiment, the oxide layer OL may be formed on the third outer surface 401 of the terminal portion 410 of the terminal plate 400 , but is not limited thereto.

[0103] In one embodiment, the third contact terminal CP3, which may be the outside of one contact terminal of the device, contacts the third outer surface 401 of the terminal portion 410 of the terminal plate 400, which may be the cathode terminal of the rechargeable battery 1003. In one embodiment, the other contact terminal of the device may contact the first outer surface 201 of the housing 200, which may be the anode terminal of the rechargeable battery 1003.

[0104] Due to the third concavo-convex shape PD3 in the third outer surface 401 of the terminal portion 410 of the terminal plate 400, a plurality of third convex portions P3 included in the third concavo-convex shape PD3 are in contact with the third contact terminal CP3, and the contact area between the third outer surface 401 of the terminal portion 410 of the terminal plate 400 and the third contact terminal CP3 is reduced, and the pressure between the third outer surface 401 of the terminal portion 410 of the terminal plate 400 and the third contact terminal CP3 is increased. Due to the increase in pressure between the third outer surface 401 of the terminal portion 410 of the terminal plate 400 and the third contact terminal CP3, the oxide layer OL formed on the third outer surface 401 may be destroyed by the pressure between the third outer surface 401 and the third contact terminal CP3 and separated from the third outer surface 401, and the third convex portion P3 of the third outer surface 401 may be in direct contact with the third contact terminal CP3.

[0105] In one embodiment, the oxide layer OL is between the third concave portion D3 of the third concavo-convex shape PD3 and the third contact terminal CP3, and the oxide layer OL is damaged by pressure and is not between the third convex portion P3 of the third concavo-convex shape PD3 and the third contact terminal CP3.

[0106] That is, even if an oxide layer OL is formed on the third outer surface 401 of the terminal portion 410 of the terminal plate 400 of the rechargeable battery 1003, as the contact area between the third outer surface 401 and the third contact terminal CP3 decreases due to the third concave-convex shape PD3 and the pressure between the third outer surface 401 and the third contact terminal CP3 increases, since the oxide layer OL formed on the surface of the third convex portion P3 of the third concave-convex shape PD3 of the third outer surface 401 is destroyed by the pressure and the third convex portion P3 of the third outer surface 401 is in direct contact with the third contact terminal CP3, the increase in contact resistance between the third outer surface 401 of the terminal portion 410 of the terminal plate 400, which can be the cathode terminal of the rechargeable battery 1003, and the third contact terminal CP3 of the device is suppressed.

[0107] In addition, even if the contact probe contacts the third outer surface 401 of the terminal portion 410 of the terminal plate 400 for testing the rechargeable battery 1003, as the contact area between the third outer surface 401 and the contact probe is reduced due to the third concave-convex shape PD3 and the pressure between the third outer surface 401 and the contact probe is increased, since the oxide layer OL formed on the surface of the third convex portion P3 of the third concave-convex shape PD3 of the third outer surface 401 is destroyed by the pressure and the third convex portion P3 of the third outer surface 401 is in direct contact with the contact probe, the increase in contact resistance between the contact probe and the third outer surface 401 of the terminal portion 410 of the terminal plate 400, which can be the cathode terminal of the rechargeable battery 1003, is suppressed, thereby improving the reliability of the test of the rechargeable battery 1003.

[0108] That is, even if an oxide layer OL is formed on the third outer surface 401 of the terminal portion 410 of the terminal plate 400, which is the outer surface of the rechargeable battery 1003, a rechargeable battery 1003 is provided as follows: in the rechargeable battery 1003, an increase in the contact resistance between the rechargeable battery 1003 and the third contact terminal CP3 of the device is suppressed, and an increase in the contact resistance between the rechargeable battery 1003 and a contact probe for testing the rechargeable battery 1002 is suppressed.

[0109] While the invention has been described in conjunction with what are presently considered to be some practical embodiments, it should be understood that the invention is not limited to the disclosed embodiments, but is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.

Claims

1. A rechargeable battery comprising: an electrode assembly comprising a first electrode, a second electrode, and a separator between the first electrode and the second electrode; a housing connected to the first electrode and accommodating the electrode assembly, and including an opening to receive the electrode assembly; a cover plate coupled to the housing to cover a peripheral area of ​​the opening and including a through hole to expose a central area of ​​the opening; and a terminal plate, which is bonded to the outer surface of the cap plate through a sealing portion and insulated from the cap plate to cover the through hole and is connected to the second electrode, The outer surface of the shell has a first concave-convex shape, wherein the outer surface of the cover plate has a second concave-convex shape, and The sealing portion is heat-fused between a portion of the second concavo-convex shape and the terminal plate, and another portion of the second concavo-convex shape is exposed to the outside. 2 . The rechargeable battery according to claim 1 , wherein the outer surface of the case contacts an external first contact terminal.

3. The rechargeable battery according to claim 2, wherein The oxide layer is between the concave portion of the first concavo-convex shape and the first contact terminal, and The oxide layer is not between the convex portion of the first concavo-convex shape and the first contact terminal. 4 . The rechargeable battery according to claim 1 , wherein the first concavo-convex shape is formed by etching using a laser beam. 5 . The rechargeable battery of claim 1 , wherein the first concavo-convex shape includes at least one of a comb-teeth shape, a checkerboard shape, a circular shape, and an elliptical shape on a plane. 6 . The rechargeable battery of claim 1 , wherein the outer surface of the cap plate contacts an external second contact terminal.

7. The rechargeable battery according to claim 6, wherein The oxide layer is between the concave portion of the second concavo-convex shape and the second contact terminal, and The oxide layer is not between the convex portion of the second concavo-convex shape and the second contact terminal.

8. The rechargeable battery according to claim 1, wherein the terminal plate comprises: A terminal portion is arranged on the cover plate; and A protrusion protrudes from the terminal portion to pass through the through hole and is connected to the second electrode. 9 . The rechargeable battery according to claim 8 , wherein the sealing portion is between the terminal portion and the cap plate. 10 . The rechargeable battery according to claim 8 , wherein an outer surface of the terminal part has a third concavo-convex shape. 11 . The rechargeable battery of claim 10 , wherein the outer surface of the terminal part contacts an external third contact terminal.

12. The rechargeable battery according to claim 11, wherein An oxide layer is between the concave portion of the third concavo-convex shape and the third contact terminal, and The oxide layer is not between the convex portion of the third concavo-convex shape and the third contact terminal.

13. The rechargeable battery according to claim 1, wherein The housing and the cover plate have the same polarity as that of the first electrode, and The terminal plate has the same polarity as that of the second electrode.

14. The rechargeable battery according to claim 1, wherein the electrode assembly further comprises: a first electrode tab extending from the first electrode and coupled to the housing; and A second electrode tab extends from the second electrode and is coupled to the terminal plate.

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