阅读说明：本技术 可再充电电池 (Rechargeable battery ) 是由 高希定 金基正 朴容辰 禹炳喆 李钟夏 于 2021-04-20 设计创作，主要内容包括：一种可再充电电池包括：壳体,接纳电极组件并包括开口；盖组件,包括联接到所述壳体并覆盖所述开口的盖板和联接到所述盖板的端子板；和外壳,覆盖所述盖板并联接到所述壳体,并且所述端子板的外表面比所述外壳的外表面更突出以具有高度差。(A rechargeable battery includes: a case receiving the electrode assembly and including an opening; a cap assembly including a cap plate coupled to the case and covering the opening and a terminal plate coupled to the cap plate; and a case covering the cap plate and coupled to the case, and an outer surface of the terminal plate protrudes more than an outer surface of the case to have a height difference.)

1. A rechargeable battery, comprising:

a case receiving the electrode assembly and including an opening;

a cap assembly including a cap plate coupled to the case and covering the opening and a terminal plate coupled to the cap plate; and

a case covering the cap plate and coupled to the case,

wherein an outer surface of the terminal plate protrudes more than an outer surface of the case to have a height difference.

2. The rechargeable battery according to claim 1, wherein

The electrode assembly includes a first electrode, a second electrode, and a separator between the first electrode and the second electrode,

the case is connected to the first electrode through a first electrode tab, and

the terminal plate is connected to the second electrode through a second electrode tab.

3. The rechargeable battery according to claim 2, wherein

The cover plate is electrically connected to the housing, and

the cap plate and the terminal plate are thermally fused with a thermal fusion member therebetween and are electrically insulated from each other.

4. The rechargeable battery according to claim 2, wherein

The terminal plate includes:

a flange part between the cap plate and the electrode assembly, electrically insulated from an inner surface of the cap plate, and attached to the inner surface of the cap plate; and

a protruding terminal protruding from the center of the flange part to the outside, passing through the terminal hole of the cap plate and the through-hole of the case, and electrically connected to the second electrode tab through the inner surface of the terminal plate, and

the protruding terminal protrudes more than the outer surface of the case by a first height difference to form an outer surface of the rechargeable battery.

5. The rechargeable battery according to claim 4, wherein the housing comprises:

a plane portion covering an outer surface of the cover plate; and

a side portion extending along a side surface of the housing at an outer side of the planar portion to cover a portion of the side surface of the housing and coupled to the side surface of the housing.

6. The rechargeable battery of claim 5, wherein the housing is formed of an electrically insulating material.

7. The rechargeable battery according to claim 6, wherein the through-hole of the case is concentric with the terminal hole of the cap plate, and an inner diameter of the through-hole of the case is larger than an outer diameter of the protruding terminal.

8. The rechargeable battery according to claim 5, wherein an inner diameter of the case is larger than a sum of an outer diameter of the protruding terminal and twice a diametrical distance of the flat portions provided on both sides in a diametrical direction of the protruding terminal.

9. The rechargeable battery according to claim 6, wherein the housing comprises PP, PE, PET, PEN resin or rubber.

10. The rechargeable battery according to claim 2, wherein the terminal plate includes:

a flange portion on and electrically insulated from and attached to an outer surface of the cap plate; and

a tab connection part protruding from the center of the flange part to the inside and protruding toward the electrode assembly through the through-hole of the case and the terminal hole of the cap plate, and electrically connected to the second electrode tab through an inner surface of the tab connection part, and

the flange portion protrudes more than the outer surface of the housing by a second height difference to form an outer surface of the rechargeable battery.

11. The rechargeable battery of claim 10, wherein the housing comprises:

a flat portion including a through hole having an inner diameter larger than an outer diameter of the flange portion to cover an exposed surface of the cover plate while exposing the flange portion; and

a side portion extending along a side surface of the housing at an outer side of the planar portion to cover a portion of the side surface of the housing and coupled to the side surface of the housing.

12. The rechargeable battery according to claim 11, wherein an inner diameter of the case is larger than a sum of an outer diameter of the flange portion and twice a diametrical distance of the flat portions provided on both sides in a diametrical direction of the flange portion.

13. The rechargeable battery according to claim 1, wherein the housing forms a step on a side of the case.

14. The rechargeable battery according to claim 1, wherein

The housing defines a first diameter in a diametrical direction at a lower portion of the housing, and

the outer shell is coupled to an upper portion of the housing and defines a second diameter diametrically larger than the first diameter.

Technical Field

Aspects of embodiments of the present invention relate to a rechargeable battery.

Background

Unlike a primary battery that cannot be recharged, a rechargeable battery can be repeatedly charged and discharged. Low capacity rechargeable batteries are used in portable small electronic devices such as mobile phones, notebook computers, and camcorders. Large-capacity batteries are widely used as power sources for driving motors such as those for hybrid vehicles.

Representative rechargeable batteries include nickel-cadmium (Ni-Cd) batteries, nickel-metal hydride (Ni-MH) batteries, lithium (Li) batteries, and lithium-ion (Li-ion) rechargeable batteries. In particular, the lithium ion rechargeable battery has an operating voltage about three times higher than that of a nickel cadmium battery or a nickel hydrogen battery, which is mainly used as a power source for portable electronic devices. In addition, lithium ion rechargeable batteries are widely used because of their high energy density per unit weight.

In particular, as the demand for wearable devices such as headsets, in-ear headsets, smart watches, and body-attached medical devices using bluetooth increases, the demand for rechargeable batteries with high energy density and ultra-small size is increasing.

The subminiature rechargeable battery has the following aspects: ensuring the required capacitance in a limited size, achieving an effective structure while increasing an effective low weight, and improving structural stability.

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.

Disclosure of Invention

According to an aspect of an embodiment of the present invention, a subminiature rechargeable battery is provided. According to an aspect of embodiments of the present invention, there is provided a rechargeable battery that can prevent reverse insertion when inserted into a set (set) and can prevent external short-circuiting of portions having different polarities (e.g., a terminal plate and a cap plate or a case).

According to another aspect of embodiments of the present invention, a rechargeable battery is provided in which terminal plates and a case having different polarities may be smoothly contacted with a kit when inserted into the kit.

According to one or more embodiments of the present invention, a rechargeable battery includes: a case receiving the electrode assembly and including an opening; a cap assembly including a cap plate coupled to the case and covering the opening and a terminal plate coupled to the cap plate; and a case covering the cap plate and coupled to the case, wherein an outer surface of the terminal plate protrudes more than an outer surface of the case to have a height difference.

The electrode assembly may include a first electrode, a second electrode, and a separator between the first electrode and the second electrode, the case may be connected to the first electrode by a first electrode tab, and the terminal plate may be connected to the second electrode by a second electrode tab.

The cap plate may be electrically connected to the case, and the cap plate and the terminal plate may be thermally fused with a thermal fusion member therebetween and may be electrically insulated from each other.

The terminal plate may include: a flange part disposed between the cap plate and the electrode assembly, and electrically insulated from and attached to an inner surface of the cap plate; and a protruding terminal protruding from the center of the flange part to the outside, passing through the terminal hole of the cap plate and the through-hole of the case, and electrically connected to the second electrode tab through an inner surface of the terminal plate, and the protruding terminal may protrude more than the outer surface of the case by a first height difference to form an outer surface of the rechargeable battery.

The housing may include: a plane portion covering an outer surface of the cover plate; and a side portion extending along a side surface of the housing at an outer side of the planar portion to cover a portion of the side surface of the housing and coupled to the side surface of the housing.

The housing may be formed of an electrically insulating material to prevent an electrical short between an outer surface of the protruding terminal and the outer surface of the cap plate.

The through hole of the housing may be concentric with the terminal hole of the cap plate, and an inner diameter of the through hole may be larger than an outer diameter of the protruding terminal.

The inner diameter of the housing may be larger than the sum of the outer diameter of the protruding terminal and twice the diametrical distance of the flat portions provided on both sides in the diametrical direction of the protruding terminal.

The housing may comprise PP, PE, PET, PEN resin or rubber.

The terminal plate may include: a flange portion on and electrically insulated from and attached to an outer surface of the cap plate; and a tab connection part protruding inward from the center of the flange part and protruding toward the electrode assembly through the through-hole of the case and the terminal hole of the cap plate, and electrically connected to the second electrode tab through an inner surface of the tab connection part, and the flange part may protrude more than the outer surface of the case by a second height difference to form an outer surface of the rechargeable battery.

The housing may include: a flat portion including a through hole having an inner diameter larger than an outer diameter of the flange portion to cover an exposed surface of the cover plate while exposing the flange portion; and a side portion extending along a side surface of the housing at an outer side of the planar portion to cover a portion of the side surface of the housing and coupled to the side surface of the housing.

The inner diameter of the housing may be larger than the sum of the outer diameter of the flange portion and twice the diametrical distance of the flat surface portions provided on both sides in the diametrical direction of the flange portion.

The housing may form a step on a side of the case.

The housing may define a first diameter in a diametrical direction at a lower portion of the housing, and the housing may be coupled to an upper portion of the housing and define a second diameter in a diametrical direction that is larger than the first diameter.

As described above, the rechargeable battery according to one or more embodiments of the present invention forms a step on the side of the case as the case covers the cap plate and is coupled to the case. In other words, since the housing protrudes more than the side of the case at the cover plate and its adjacent side, a step of increasing height or diameter may be formed. Therefore, the rechargeable battery can be effectively prevented from being inserted into the kit in a reverse direction visually or structurally.

In the rechargeable battery according to one or more embodiments, two portions (e.g., a cap plate and a terminal plate) having different polarities in the cap assembly are exposed in the same direction, and the case may cover at least one of the two portions having different polarities. When the housing is formed of an electrically insulating material, external short-circuiting of the two parts by the conductive particles can be effectively prevented.

Further, since the rechargeable battery according to one or more embodiments combines the case to the case, the case serves as a buffer of physical impact, so that safety in a drop test and a rollover test may be improved.

In the rechargeable battery according to one or more embodiments, the terminal plate protrudes more than the case despite the case is applied, so that the terminal plate and the case can be smoothly contacted with the kit when inserted into the kit.

Drawings

Fig. 1 is a perspective view of a rechargeable battery according to an embodiment of the present invention.

Fig. 2 is an exploded perspective view of the rechargeable battery of fig. 1.

Fig. 3 is a sectional view taken along line III-III in fig. 1.

Fig. 4 is a perspective view of a rechargeable battery according to an embodiment of the present invention.

Fig. 5 is an exploded perspective view of the rechargeable battery of fig. 4.

Fig. 6 is a sectional view taken along line VI-VI in fig. 4.

Description of the reference numerals

1. 2: the rechargeable battery 10: electrode assembly

11: first electrode 12: second electrode

13: separator 14: insulating sheet

20: the housing 21: opening of the container

30. 60: the lid assembly 31: cover plate

33. 63: terminal plate 34: hot melt component

40. 70: housing 41, 71: plane part

42. 72: side 51: first electrode lug

52: second electrode tabs 61, 62: insulating member

611. 621: through hole 101: first end

102: second end 301: exposed surface

311: terminal holes 331, 631: flange part

332. 632: the protruding terminal 341: through hole

411. 711: a through hole D: diameter of battery

D1, D2: inner diameters D11, D21: outer diameter

D12, D22: diameter direction distance H: height

H1, H2: height-direction lengths G1 and G2: a first gap and a second gap

P1, P3: expanded portions P2, P4: non-expanded part

Δ H1, Δ H2: the first height difference and the second height difference

Detailed Description

The present invention will be described more fully hereinafter with reference to the accompanying drawings, in which exemplary embodiments of the invention are shown. As will be realized by the person skilled in the art, the described embodiments can be modified in various different ways, all without departing from the scope of the invention. The drawings and description are to be regarded as illustrative in nature, and not as restrictive. Like reference numerals refer to like elements throughout the specification.

Furthermore, unless expressly stated to the contrary, it is understood that terms such as "comprising," "including," or "having," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, components, and/or groups thereof, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

In addition, in the present specification, it will be understood that when a component is referred to as being "connected" or "coupled" to another component, it can be directly connected or coupled to the other component or be connected or coupled to the other component with one or more other components interposed therebetween.

The singular forms will include the plural forms unless the context clearly dictates otherwise.

It will 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. For example, a first element could be termed a "second" element, and, similarly, a second element could be termed a "first" element, without departing from the scope of example embodiments of the present inventive concept. Terms in the singular may include the plural unless the context clearly dictates otherwise.

Further, terms such as "below", "lower", "above", "upper", and the like 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.

Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the inventive concepts belong. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

The rechargeable battery according to an embodiment of the present invention is an ultra-compact battery, which may be a coin battery or a button battery. Here, the coin battery or the button battery is a thin coin-type battery or a button-type battery, and refers to a battery having a height (H) of 1 or less and a diameter (D) ratio (H/D) (see fig. 1).

In one embodiment, the coin or button cell is generally cylindrical and the horizontal cross-section is circular, but the invention is not limited thereto and the horizontal cross-section may be oval or polygonal. In this case, the diameter is determined as the maximum distance of the outer circumference of the case (or housing) based on the horizontal direction of the battery, and the height is determined as the maximum distance (distance from the flat bottom to the flat top cross-section) based on the vertical direction of the battery.

However, the present invention is not limited to the coin battery or the button battery as an example of the present invention, and the battery of the present invention may be a cylindrical battery or a pin-type battery. Herein, a case where the rechargeable battery according to an embodiment of the present invention is a coin battery or a button battery will be further described in detail as an example.

Fig. 1 is a perspective view of a rechargeable battery according to an embodiment of the present invention; fig. 2 is an exploded perspective view of the rechargeable battery of fig. 1; fig. 3 is a sectional view taken along line III-III in fig. 1.

Referring to fig. 1 to 3, a rechargeable battery 1 according to an embodiment includes an electrode assembly 10, a case 20, a cap assembly 30, and a case 40. The cap assembly 30 includes a cap plate 31 and a terminal plate 33 combined together. As an example, the cap plate 31 and the terminal plate 33 are thermally fused by a thermal fusion member 34 disposed therebetween.

The heat fusion member 34 serves as a medium for connecting the cap plate 31 and the terminal plate 33 to each other. For example, the heat fusing member 34 may be formed of an electrically insulating material such as a polymer, and may be melted using a laser or the like to be fused to the cap plate 31 and the terminal plate 33.

In an embodiment, by coupling the terminal plate 33 to the cap plate 31 using the heat fusion member 34, a stable coupling structure can be formed while effectively insulating between the terminal plate 33 and the cap plate 31 without adding a separate insulation configuration.

Since the coin battery is manufactured in an ultra-compact size, it may have design limitations in terms of space, and accordingly, the function is ensured while simplifying its structure and manufacturing process. In this regard, in this embodiment, the insulation and coupling between the terminal plate 33 and the cap plate 31 are achieved by the heat fusion member 34.

The electrode assembly 10 includes a first electrode 11 (e.g., a negative electrode) and a second electrode 12 (e.g., a positive electrode) provided on respective sides of a separator 13 as an electrically insulating material, and the electrode assembly 10 is formed by winding the first electrode 11, the separator 13, and the second electrode 12. Accordingly, in one embodiment, the electrode assembly 10 may be formed in a jelly-roll type. Although not separately shown, in an embodiment, the electrode assembly may be formed in a stacking type.

The electrode assembly 10 is configured to be charged and discharged, and a winding axis of the electrode assembly 10 may be arranged parallel to a height direction of the case 20 (a vertical direction in fig. 1 to 3). In an embodiment, the first end (lower surface of the electrode assembly) 101 and the second end (upper surface of the electrode assembly) 102 of the electrode assembly 10 may be flat and parallel to each other. In an embodiment, the electrode assembly 10 is not provided with a center pin, but a center pin (not shown) may be provided at a position of the winding axis.

The case 20 receives the electrode assembly 10 while facing the first end 101 of the electrode assembly 10. In one embodiment, electrode assembly 10 is covered by insulating sheet 14 and is built into case 20. As an example, the case 20 is formed as a cylinder accommodating the jelly-roll type electrode assembly 10, and the cap assembly 30 seals the opening 21 of the cylindrical case 20.

In one embodiment, the electrode assembly 10 includes a first electrode tab 51 connected to the first electrode 11 and a second electrode tab 52 connected to the second electrode 12, and the first electrode 11 and the second electrode 12 are drawn to the first end 101 and the second end 102, respectively.

In a state in which the electrode assembly 10 is received 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 33 of the cap assembly 30.

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 electrode assembly 10 to cover the opening 21. In this way, the terminal plate 33 is coupled to the second electrode tab 52 at the same time as the cap plate 31 coupled with the heat fusing member 34.

Here, a case where the first electrode 11 and the second electrode 12 are a negative electrode and a positive electrode, respectively, will be described as an example, but the present invention is not limited thereto, and the first electrode 11 and the second electrode 12 may be a positive electrode and a negative electrode, respectively.

In one embodiment, the first electrode (negative electrode) 11 is formed in a long extended stripe shape, and includes a negative electrode coating portion, which is a region where a current collector of a metal foil (e.g., a copper foil) is coated with a negative electrode active material layer, and a negative electrode non-coating portion, which is a region where an active material is not coated. The negative electrode uncoated portion may be disposed at an end portion in a length direction of the negative electrode.

In an embodiment, the second electrode (positive electrode) 12 is formed in a long extended strip shape, and includes a positive electrode coating portion, which is a region where a current collector of a metal foil (e.g., aluminum foil) is coated with a positive electrode active material layer, and a positive electrode non-coating portion, which is a region where an active material is not coated. The positive electrode uncoated portion may be disposed at an end in a length direction of the positive electrode.

The case 20 allows the electrode assembly 10 to be inserted into an opening 21 formed at one side of the case 20, and has a space for accommodating the electrode assembly 10 and an electrolyte therein. For example, the case 20 may be formed in a cylindrical shape having a height H smaller than a diameter D thereof, and may have a circular opening 21 so that the electrode assembly 10 having a cylindrical shape corresponding to the inner space of the case 20 may be inserted.

In the cap assembly 30, the terminal plate 33 includes a flange portion 331 and a protruding terminal 332. The flange portion 331 is disposed between the cap plate 31 and the electrode assembly 10 to be electrically insulated from the inner surface of the cap plate 31 and attached to the inner surface of the cap plate 31.

The housing 40 is provided to prevent or substantially prevent reverse insertion when assembling the rechargeable battery 1 into the kit. As an example, the case 40 covers the cap plate 31 and is coupled to the case 20 to form an expanded portion P1 in the rechargeable battery 1. That is, the housing 40 forms a step on the side of the case 20 by the expanded portion P1.

Therefore, the case 40 defines both sides in the height direction (up-down direction) of the rechargeable battery 1 as an expanded portion P1 on the upper side and a non-expanded portion P2 on the lower side. That is, in the rechargeable battery 1, a portion to which the case 40 is coupled forms the expanded portion P1, and a portion to which no case 40 is coupled forms the non-expanded portion P2.

In the non-expanded portion P2, the case 20 has the negative characteristics of the first electrode 11, and in the expanded portion P1, the terminal plate 33 has the positive characteristics of the second electrode 12. In an embodiment, the cap plate 31 coupled to the case 20 has the negative characteristics of the first electrode 11 together with the case 20. That is, the cap plate 31 and the case 20 are electrically connected to each other.

In the terminal plate 33, the protruding terminal 332 protrudes from the center of the flange portion 331 to the outside, and passes through the terminal hole 311 of the cap plate 31, the through-hole 341 of the thermal fusing member 34, and the through-hole 411 of the case 40, and the inner surface of the protruding terminal 332 is electrically connected to the second electrode tab 52. The second electrode tab 52 may be connected to an inner surface of the flange portion 331 or an inner surface of the protruding terminal 332, or may be connected to both.

The protruding terminal 332 protrudes more than the outer surface of the case 40 by the first height difference Δ H1 to form the outer surface of the rechargeable battery 1. That is, the outer surface of the protruding terminal 332 protrudes more than the outer surface of the cap plate 31 with respect to the bottom of the housing 20. Further, the outer surface of the protruding terminal 332 and the outer surface of the housing 40 form planes that are spaced apart from each other in the diameter direction while having the first height difference Δ H1.

In one embodiment, the housing 40 includes a planar portion 41 and a side portion 42. The planar portion 41 is configured to cover the outer surface of the cover plate 31 while exposing the protruding terminal 332 through the through-hole 411. The side portion 42 extends along a side surface of the housing 20 outside the planar portion 41 to cover a part of the side surface of the housing 20 and is coupled to the side surface of the housing 20. In the rechargeable battery 1, a portion combined with the case 40 forms the expanded portion P1, and a portion without the case 40 forms the non-expanded portion P2.

Therefore, the housing 40 forms a step on the side surface of the case 20 at the boundary between the expanded portion P1 and the non-expanded portion P2 in the height direction and the intersecting direction (diameter direction) orthogonal to the height direction. That is, the expanded portion P1 relatively increases in height or diameter as compared to the non-expanded portion P2.

In the case 20, the outer shell 40 is not combined at the lower portion, thereby defining the outer diameter (i.e., the first diameter) of the case 20 between the outside in the diameter direction of the case 20. The outer shell 40 is coupled to an upper portion of the housing 20 to define an outer diameter (i.e., a second diameter) of the outer shell 40 between diametrically outer sides of the outer shell 40. The outer diameter of the housing 40 is larger than the outer diameter of the housing 20. Therefore, there is a difference in diameter between the upper and lower portions of the rechargeable battery 1.

In an embodiment, the housing 40 may be formed of an electrically insulating material to prevent or substantially prevent an electrical short between the outer surface of the protruding terminal 332 and the outer surface of the cap plate 31. For example, the case 40 may include or be made of polypropylene (PP), Polyethylene (PE), polyethylene terephthalate (PET), polyethylene naphthalate (PEN) resin or rubber. Although not shown, any synthetic resin or electrically insulating material may be applied to the housing.

In one embodiment, the through-hole 411 of the housing 40 is concentric with the terminal hole 311 of the cap plate 31, and the inner diameter of the through-hole 411 is formed to be larger than the outer diameter D11 of the protruding terminal 332. Therefore, the inner diameter D1 of the housing 20 is larger than the sum of the outer diameter D11 of the projecting terminal 332 and twice the diametrical distance D12 of the flat surface portions 41 provided on both sides in the diametrical direction of the projecting terminal 332 (D1 > D11+2 × D12). As shown in fig. 3, the diametrical distance D12 of the planar portion 41 refers to the distance from the inner side of the planar portion 41 to the portion of the planar portion 41 corresponding to the inner side wall of the housing 20, measured in the diametrical direction of the housing 40. That is, a first gap G1 exists between the outer surface of the protruding terminal 332 and the inner wall of the through-hole 411 of the housing 40.

When the side portion 42 of the housing 40 is coupled to the case 20 and the flat portion 41 is in close contact with the cover plate 31, the first gap G1 prevents or substantially prevents the protruding terminal 332 from blocking the area around the through-hole 411.

In one embodiment, an insulating member 61 provided at the outer periphery in the diameter direction of the heat fusion member 34 is mounted on the inner surface of the cap plate 31. The insulating member 61 may form an electrical insulating structure between the cap plate 31 and the second electrode tab 52 and between the cap plate 31 and the electrode assembly 10. As an example, the insulating member 61 has a through hole 611 corresponding to the outer diameter of the heat fusion member 34.

In one embodiment, in the housing 40, the diametrical distance D12 of the planar portion 41 may be greater than or equal to the height-wise length H1 of the side portion 42 (D12 ≧ H1). Therefore, the length H1 in the height direction generates a fastening force of the case 40 to the housing 20, and the diametrical distance D12 allows the insulating performance of the terminal plate 33 to be sufficiently ensured.

In an embodiment, referring to fig. 1, in the rechargeable battery 1, a height H is defined as a distance between an outer plane of the case 20 and an outer plane of the protruding terminal 332 in a state where the opening 21 of the case 20 is closed and sealed by the cover assembly 30, and a battery diameter D is defined by an outer circumference of the case 40. In one embodiment, the ratio of the height H to the cell diameter D is 1 or less (H/D ≦ 1). Therefore, the rechargeable battery 1 of the present embodiment may be a coin-type battery or a button-type battery, and may be formed in a thin coin or button shape.

Here, another embodiment of the present invention is described. By comparing the first embodiment and the second embodiment, it is possible to omit the description of the same configuration and mainly describe a different configuration with respect to the second embodiment.

Fig. 4 is a perspective view of a rechargeable battery according to an embodiment of the present invention; fig. 5 is an exploded perspective view of the rechargeable battery of fig. 4; fig. 6 is a sectional view taken along line VI-VI in fig. 4.

Referring to fig. 4 to 6, in the rechargeable battery 2 according to an embodiment, the terminal plate 63 of the cap assembly 60 includes a flange portion 631 and a tab connection portion 632. The flange portion 631 is disposed outside the cap plate 31, and is electrically insulated from and attached to an outer surface of the cap plate 31.

The housing 70 is provided to prevent or substantially prevent reverse insertion when assembling the rechargeable battery 2 into the kit. As an example, the case 70 covers the cap plate 31 and is coupled to the case 20 to form the expanded portion P3 in the rechargeable battery 2. On the cover plate 31, a part of the outer surface is covered with the flange portion 631, and the flat surface (exposed surface 301) of the remaining part of the outer surface is covered with the housing 70.

In the terminal plate 63, the tab connection part 632 protrudes from the center of the flange part 631 to the inside, and protrudes toward the electrode assembly 10 through the through hole 711 of the case 70, the through hole 341 of the hot melt member 34, and the terminal hole 311 of the cap plate 31, and the second electrode tab 52 is electrically connected to the inner surface of the tab connection part 632.

The flange portion 631 protrudes more than the outer surface of the case 70 by the second height difference Δ H2 to form the outer surface of the rechargeable battery 2. In other words, the outer surface of the flange portion 631 protrudes more than the outer surface of the cap plate 31 with respect to the bottom of the case 20. In addition, the outer surface of the flange portion 631 and the outer surface of the housing 70 form planes that are spaced apart from each other in the diameter direction while having the second height difference Δ H2.

For example, the housing 70 includes a flat portion 71 and a side portion 72. Planar portion 71 has through hole 711, and is configured to cover exposed surface 301 of the outer surface of lid plate 31 while exposing flange portion 631 of terminal plate 63. The side portion 72 extends along a side surface of the housing 20 outside the flat portion 71 to cover a portion of the side surface of the housing 20 and is coupled to the side surface of the housing 20. In the rechargeable battery 2, a portion of the case 70 combined with the case 20 forms an expanded portion P3, and a portion without the case 70 forms a non-expanded portion P4.

The case 70 covers the exposed surface 301 of the cover plate 31 and is bonded to the case 20 to form an expanded portion P3. That is, the housing 70 forms a step on the side of the case 20 by the expanded portion P3. That is, the expanded portion P3 relatively increases in height or diameter as compared to the non-expanded portion P4.

In one embodiment, the through hole 711 of the case 70 is concentric with the terminal hole 311 of the cap plate 31, and the inner diameter of the through hole 711 is formed to be larger than the outer diameter D21 of the flange portion 631. Therefore, the inner diameter D2 of the housing 20 is larger than the sum of the outer diameter D21 of the flange portion 631 and twice the diametrical distance D22 of the flat surface portions 71 provided on both sides in the diametrical direction of the flange portion 631 (D2 > D21+2 × D22). As shown in fig. 6, a diametrical distance D22 of the planar portion 71 refers to a distance from an inner side of the planar portion 71 to a portion of the planar portion 71 corresponding to an inner side wall of the housing 20, measured in a diametrical direction of the case 70.

That is, a second gap G2 exists between the outer surface of the flange portion 631 and the inner wall of the through hole 711 of the housing 70.

The insulating member 62 provided at the outer circumference of the lug connection portion 632 in the diameter direction is mounted on the inner surface of the cap plate 31. The insulating member 62 may form an electrical insulating structure between the cap plate 31 and the second electrode tab 52 and between the cap plate 31 and the electrode assembly 10. As an example, the insulating member 62 has a through hole 621 corresponding to the terminal hole 311 of the cap plate 31. The through hole 621 allows the second electrode tab 52 to be connected to the inner surface of the tab connection part 632. The through hole 621 is formed to have a smaller diameter than the terminal hole 311, thereby preventing or substantially preventing the second electrode tab 52 from contacting the cap plate 31.

In the case 70, the diametrical distance D22 of the planar portion 71 may be less than or equal to the height-directional length H2 of the side portion 72 (D22. ltoreq.H 2). Therefore, the diametrical distance D22 is shorter than the diametrical distance D12 of the first embodiment, but the height direction length H2 allows the fastening force of the housing 70 to the case 20 to be sufficiently ensured.

While the invention has been described in connection with what is presently considered to be some practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments. On the contrary, it is intended to cover various modifications and equivalent arrangements included within the scope of the appended claims.