Sealed battery

Abstract

A nonaqueous electrolyte secondary battery (10) is provided with a bottomed tubular outer can (16) accommodating an electrode body (14), and a sealing body (17) for sealing an opening portion of the outer can (16). A crimped portion (31) for crimping and securing the sealing body (17) is formed in the outer can (16) by bending the edge portion of the opening portion inward in the radial direction, and the sealing body (17) includes a rupture disk (24), a cathode cap (27) including a flange (27a), and a metal height adjusting portion (40) for adjusting the height of the crimped portion (31).

Description

[Technical Field]

[0001] The present disclosure relates to a sealed battery, and more particularly to a sealing of a battery outer can. [Background technology]

[0002] Cylindrical nonaqueous electrolyte secondary batteries are widely known, each of which includes a bottomed cylindrical outer can, a sealing body that closes the opening of the outer can, and a gasket interposed between the outer can and the sealing body. The outer can generally has a crimped portion formed by bending the edge of the opening inward and pressing the sealing body against the gasket via the crimped portion. In a nonaqueous electrolyte secondary battery, for example, a positive electrode lead is connected to the inner surface of the sealing body, making the sealing body the positive electrode external terminal, and a negative electrode lead is connected to the inner surface of the outer can, making the outer can the negative electrode external terminal.

[0003] The applications of sealed batteries, particularly non-aqueous electrolyte secondary batteries, are expanding to include automotive applications, power generation, and energy storage. To accommodate these applications, a large number of batteries are connected in series and parallel to form modules for installation in products. In recent years, a modular approach has been adopted in which batteries are arranged in a single direction, primarily for the purpose of improving productivity and design aspects such as module space efficiency. In this case, the external lead is welded to the positive electrode cap and the crimped portion of the outer can, which is the negative electrode side. To ensure welding quality and improve productivity, it is necessary to achieve a desired height relationship between the positive electrode cap and the crimped portion of the outer can.

[0004] One possible solution to this problem is to lower the height of the positive electrode cap attached to the sealing body to match the height of the crimped part, but in this case, the opening of the positive electrode cap cannot be secured sufficiently, which poses a problem of reducing the battery's exhaust capacity after the safety valve is activated. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] International Publication No. 2014-017091 Summary of the Invention [Problem to be solved by the invention]

[0006] Patent Document 1 discloses a battery in which an insulating plate is placed between the sealing body and the crimped portion. The insulating plate in Patent Document 1 is provided to prevent a short circuit between the sealing body and the battery case if the gasket melts in a high-temperature environment. The material of the insulating plate is said to have lower mechanical strength than the gasket and is easily deformed when crimped, so it is not suitable for the purpose of precisely adjusting the height of the crimped portion.

[0007] An object of the present disclosure is to provide a sealed battery that can adjust the height of the crimping portion of the outer can and achieve a desired height relationship between the positive electrode cap and the crimping portion without reducing the exhaust capacity of the battery. [Means for solving the problem]

[0008] The sealed battery according to the present disclosure includes a cylindrical outer can with a bottom that houses an electrode assembly, and a sealing body that closes the opening of the outer can. The outer can has a crimped portion formed by bending the edge of the opening radially inward and crimping the sealing body to fix it. The sealing body is configured to have a rupture disk, a positive electrode cap having a flange, and a metal height adjustment portion for adjusting the height of the crimped portion. [Effects of the Invention]

[0009] The sealed battery according to the present disclosure is provided with a metallic height adjustment portion on the sealing body, making it possible to adjust the height of the external terminals. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a cross-sectional view of a nonaqueous electrolyte secondary battery according to an embodiment; [Figure 2] 2 is an enlarged cross-sectional view of the periphery of a crimped portion of a nonaqueous electrolyte secondary battery according to an embodiment of the present invention; FIG. [Figure 3]FIG. 4 is an enlarged cross-sectional view of the periphery of a crimped portion of a nonaqueous electrolyte secondary battery that is another example of the embodiment. [Figure 4] FIG. 4 is an enlarged cross-sectional view of the periphery of a crimped portion of a nonaqueous electrolyte secondary battery that is yet another example of the embodiment. [Figure 5] FIG. 4 is an enlarged cross-sectional view of the periphery of a crimped portion of a nonaqueous electrolyte secondary battery that is yet another example of the embodiment. [Figure 6] FIG. 4 is an enlarged cross-sectional view of the periphery of a crimped portion of a nonaqueous electrolyte secondary battery that is yet another example of the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. In the following description, specific shapes, materials, directions, numerical values, etc. are examples for facilitating understanding of the present disclosure and can be appropriately changed according to the application, purpose, specifications, etc. Furthermore, it is originally anticipated that the components of the embodiments and modified examples described below can be selectively combined.

[0012] In the following, a nonaqueous electrolyte secondary battery 10 will be exemplified as a sealed battery, in which an electrode body 14 is housed in a cylindrical outer can 16 with a bottom and a sealing body 17 is provided to close the opening of the outer can 16. However, the present invention can also be applied to various types of sealed batteries other than nonaqueous electrolyte secondary batteries, such as nickel-metal hydride secondary batteries.

[0013] Fig. 1 is a cross-sectional view of a nonaqueous electrolyte secondary battery 10 according to an embodiment of the present disclosure. As shown in Fig. 1, the nonaqueous electrolyte secondary battery 10 includes a cylindrical outer can 16 with a bottom, a sealing member 17 that closes the opening of the outer can 16, and a gasket 28 that is interposed between the outer can 16 and the sealing member 17. The nonaqueous electrolyte secondary battery 10 also includes an electrode assembly 14 and an electrolyte that are housed in the outer can 16. The electrode assembly 14 includes a positive electrode 11, a negative electrode 12, and a separator 13, and has a structure in which the positive electrode 11 and the negative electrode 12 are spirally wound with the separator 13 interposed therebetween.

[0014] The non-aqueous electrolyte includes a non-aqueous solvent and an electrolyte salt dissolved in the non-aqueous solvent. Examples of the non-aqueous solvent include esters, ethers, nitriles, amides, and mixtures of two or more of these. The non-aqueous solvent may contain a halogen-substituted compound in which at least a portion of the hydrogen atoms in the solvent are replaced with halogen atoms such as fluorine. The non-aqueous electrolyte is not limited to a liquid electrolyte, but may also be a solid electrolyte using a gel polymer or the like. The electrolyte salt is a lithium salt such as LiPF6.

[0015] The electrode assembly 14 has a long positive electrode 11, a long negative electrode 12, and two long separators 13. The electrode assembly 14 also has a positive electrode lead 20 joined to the positive electrode 11 and a negative electrode lead 21 joined to the negative electrode 12. The negative electrode 12 is formed to be slightly larger than the positive electrode 11 in order to suppress lithium deposition, and is formed to be longer than the positive electrode 11 in the longitudinal direction and width direction (short direction). The two separators 13 are also formed to be at least slightly larger than the positive electrode 11, and are arranged to sandwich the positive electrode 11, for example.

[0016] The positive electrode 11 has a positive electrode current collector and a positive electrode mixture layer formed on both sides of the positive electrode current collector. The positive electrode current collector can be a foil of a metal, such as aluminum or an aluminum alloy, that is stable within the potential range of the positive electrode 11, or a film with such a metal disposed on the surface layer. The positive electrode mixture layer contains a positive electrode active material, a conductive agent, and a binder. The positive electrode 11 can be produced, for example, by applying a positive electrode mixture slurry containing a positive electrode active material, a conductive agent, a binder, etc., onto the positive electrode current collector, drying the coating, and then compressing it to form a positive electrode mixture layer on both sides of the current collector.

[0017] The positive electrode active material is mainly composed of a lithium-containing metal composite oxide. Examples of metal elements contained in the lithium-containing metal composite oxide include Ni, Co, Mn, Al, B, Mg, Ti, V, Cr, Fe, Cu, Zn, Ga, Sr, Zr, Nb, In, Sn, Ta, and W. An example of a preferred lithium-containing metal composite oxide is a composite oxide containing at least one of Ni, Co, Mn, and Al.

[0018] Examples of conductive agents contained in the positive electrode mixture layer include carbon materials such as carbon black, acetylene black, ketjen black, and graphite. Examples of binders contained in the positive electrode mixture layer include fluororesins such as polytetrafluoroethylene (PTFE) and polyvinylidene fluoride (PVdF), polyacrylonitrile (PAN), polyimide, acrylic resin, and polyolefin. These resins may be used in combination with cellulose derivatives such as carboxymethyl cellulose (CMC) or its salts, and polyethylene oxide (PEO).

[0019] The negative electrode 12 has a negative electrode current collector and a negative electrode mixture layer formed on both sides of the negative electrode current collector. The negative electrode current collector can be a foil of a metal, such as copper or a copper alloy, that is stable within the potential range of the negative electrode 12, or a film with such a metal disposed on the surface layer. The negative electrode mixture layer contains a negative electrode active material and a binder. The negative electrode 12 can be produced, for example, by applying a negative electrode mixture slurry containing a negative electrode active material and a binder to the negative electrode current collector, drying the coating, and then compressing it to form a negative electrode mixture layer on both sides of the current collector.

[0020] The negative electrode active material generally uses a carbon material that reversibly absorbs and releases lithium ions. Preferred carbon materials include natural graphite such as flake graphite, lump graphite, and amorphous graphite, and artificial graphite such as lump artificial graphite and graphitized mesophase carbon microbeads. The negative electrode mixture layer may contain a Si-containing compound as the negative electrode active material. Furthermore, the negative electrode active material may include a metal other than Si that alloys with lithium, an alloy containing such a metal, or a compound containing such a metal.

[0021] The binder contained in the negative electrode mixture layer may be a fluororesin, PAN, polyimide resin, acrylic resin, polyolefin resin, or the like, as in the case of the positive electrode 11. Preferably, styrene-butadiene rubber (SBR) or a modified product thereof is used. The negative electrode mixture layer may contain, in addition to SBR, for example, CMC or a salt thereof, polyacrylic acid (PAA) or a salt thereof, polyvinyl alcohol, or the like.

[0022] The separator 13 is a porous sheet having ion permeability and insulating properties. Specific examples of the porous sheet include a microporous thin film, a woven fabric, and a nonwoven fabric. Preferred materials for the separator 13 include olefin resins such as polyethylene and polypropylene, and cellulose. The separator 13 may have either a single-layer structure or a laminated structure. A heat-resistant layer or the like may be formed on the surface of the separator 13. The negative electrode 12 may form the winding start end of the electrode assembly 14, but typically the separator 13 extends beyond the winding start end of the negative electrode 12, and the winding start end of the separator 13 becomes the winding start end of the electrode assembly 14.

[0023] In the example shown in FIG. 1 , the positive electrode lead 20 is electrically connected to an intermediate portion of the positive electrode core in the winding direction, and the negative electrode lead 21 is electrically connected to the end of the negative electrode core in the winding direction. However, the negative electrode lead may be electrically connected to the end of the negative electrode core in the winding direction. Alternatively, the electrode body may have two negative electrode leads, one of which is electrically connected to the end of the negative electrode core in the winding direction and the other negative electrode lead is electrically connected to the end of the negative electrode core in the winding direction. Alternatively, the end of the negative electrode core in the winding direction on the winding side may be abutted against the inner surface of the outer can, thereby electrically connecting the negative electrode and the outer can.

[0024] As shown in FIG. 1 , the nonaqueous electrolyte secondary battery 10 further includes an insulating plate 18 disposed above the electrode assembly 14 and an insulating plate 19 disposed below the electrode assembly 14. In the example shown in FIG. 1 , a positive electrode lead 20 attached to the positive electrode 11 passes through a through-hole in the insulating plate 18 and extends toward the sealing body 17, and a negative electrode lead 21 attached to the negative electrode 12 passes outside the insulating plate 19 and extends toward the bottom 33 of the outer can 16. The positive electrode lead 20 is connected to the underside of a terminal plate 23, which serves as the bottom plate of the sealing body 17, by welding or the like, and a positive electrode cap 27, which serves as the top plate of the sealing body 17 and is electrically connected to the terminal plate 23, serves as a positive electrode external terminal. The negative electrode lead 21 is connected to the inner surface of the bottom 33 of the outer can 16 by welding or the like, and the outer can 16 serves as a negative electrode external terminal. The structure of the sealing body 17 will be described in detail later.

[0025] The outer can 16 is a metal container having a cylindrical portion with a bottom. The space between the outer can 16 and the sealing body 17 is sealed with an annular gasket 28, which seals the internal space of the battery. The gasket 28 is sandwiched between the outer can 16 and the sealing body 17 and insulates the sealing body 17 from the outer can 16. The gasket 28 serves as a sealing material to maintain airtightness inside the battery and prevents leakage of the electrolyte. The gasket 28 also serves as an insulating material to prevent short-circuiting between the outer can 16 and the sealing body 17.

[0026] The outer can 16 has a grooved portion 32 formed on a portion of the cylindrical outer surface in the height direction of the outer can 16, thereby forming a convex portion on the inner periphery that protrudes radially inward. The grooved portion 32 can be formed, for example, by spinning a portion of the cylindrical outer surface radially inward to recess it radially inward. The outer can 16 has a bottomed tubular portion 30 including the grooved portion 32 and an annular crimped portion 31. The bottomed tubular portion 30 accommodates the electrode assembly 14 and the nonaqueous electrolyte, and the crimped portion 31 is bent radially inward from the end of the open side of the bottomed tubular portion 30 and extends radially inward. The crimped portion 31 is formed when the upper end of the outer can 16 is bent inward and crimped to the peripheral edge of the sealing body 17. The sealing body 17 is clamped together with the gasket 28 between the crimped portion 31 and the upper side of the grooved portion 32 by the crimping, and is fixed to the outer can 16 .

[0027] (First embodiment) Next, a description will be given of the assembly process of the sealing body 17. Then, a description will be given of the height adjustment of the crimped portion 31. Fig. 2 is an enlarged cross-sectional view of the periphery of the crimped portion of the nonaqueous electrolyte secondary battery 10 according to the first embodiment of the present disclosure.

[0028] 2, sealing body 17 has terminal plate 23, insulating plate 26, rupture disk 24, positive electrode cap 27, and metal spacer 40. First, each component of sealing body 17 before assembly will be described.

[0029] The terminal board 23 is made of metal and is formed in a disk shape.

[0030] Insulating plate 26 is ring-shaped and has a rising portion 26a extending in the circumferential direction at its peripheral edge. The inner diameter of rising portion 26a of insulating plate 26 is approximately equal to the outer diameter of terminal plate 23. Upstanding portion 26a of insulating plate 26 is formed so that terminal plate 23 can be inserted therein.

[0031] The rupture disk 24 is formed in a cylindrical shape with a bottom and a standing portion 24a at the periphery. On the surface opposite to the extending direction of the standing portion 24a, a protrusion 24b is provided in the inner diameter direction and in the circumferential direction. The inner diameter of the protrusion 24b of the rupture disk 24 is approximately equal to the outer diameter of the insulating plate 26 when the terminal plate 23 is inserted. Before assembling the sealing body 17, the bending portion 24c described below is in a pre-bending state, and is bent during the assembling process of the sealing body 17.

[0032] The positive electrode cap 27 is made of metal and has a disk shape with a protruding center, and has a flange 27a extending in the outer circumferential direction. The outer diameter of the flange 27a is equal to the inner diameter of the upright portion 24a of the rupture disk 24, and is formed so that the flange 27a can be inserted into the upright portion 24a before the bent portion 24c is formed.

[0033] The metal spacer 40 is made of metal and formed into a ring shape. The inner diameter of the metal spacer 40 is larger than the outer diameter of the protruding portion of the positive electrode cap 27, and the outer diameter of the metal spacer 40 is approximately the same as the diameter of the flange 27a. The metal spacer 40 is formed so that the bent portion 24c can be inserted into the upright portion 24a before formation.

[0034] The sealing body 17 of this embodiment can be formed from these components through the following steps. Step 1: The terminal board 23 is inserted into the upright portion 26 a of the insulating board 26 . Step 2: The terminal plate 23 inserted into the insulating plate 26 is inserted into the protruding portion 24 b of the rupture disk 24 . Step 3: The protrusions 24b of the rupture disk 24 are crimped radially inward to fix the insulating plate 26 and the terminal plate 23 together. Step 4: The terminal plate 23 and the rupture disk 24 are connected at their centers by welding, thereby connecting the terminal plate 23 and the rupture disk 24 mechanically and electrically. Step 5: The positive electrode cap 27 is inserted into the upright portion 24a of the rupture disk 24. As a result, the flange 27a of the positive electrode cap 27 comes into contact with the rupture disk 24. Step 6: The outer periphery of the positive electrode cap 27 and the rupture disk 24 are welded together, thereby connecting the positive electrode cap 27 and the rupture disk 24 mechanically and electrically. Step 7: A metal spacer 40 is inserted into the upright portion 24a of the rupture disk 24 into which the positive electrode cap 27 has been inserted. Step 8: The upstanding portion 24a of the rupture disk 24 is crimped radially inward, and the end of the upstanding portion 24a is bent so as to abut on the metal spacer 40, thereby forming a ring-shaped bent portion 24c. In this way, sealing body 17 is formed. Note that this process is an example and can be changed depending on the shapes of the components. Furthermore, the order of the processes is not limited to this.

[0035] Before being attached to the sealing body 17, the gasket 28 has a cylindrical tubular portion and an annular portion extending radially inward from one axial end of the tubular portion. The inner diameter of the tubular portion is equal to or slightly smaller than the outer diameter of the sealing body 17 (the outer diameter of the rupture disk 24). The gasket 28 can be attached to the sealing body 17 by expanding the tubular portion.

[0036] The sealing body 17 has a gasket 28 attached to its peripheral edge, and is inserted into the opening of the outer can 16 before the crimped portion 31 is formed. Then, the edge of the opening is crimped radially inward to form the crimped portion 31.

[0037] The metal spacer 40 of the sealing body 17 of this embodiment serves as a height adjustment portion 40 for adjusting the height of the crimped portion 31. That is, by selecting the plate thickness of the metal spacer 40 in consideration of the thicknesses of the flange 27a, the rupture disk 24, and the gasket 28, the height of the crimped portion 31 can be formed to be the same height as the height of the positive electrode cap 27.

[0038] Next, the conditions required for the height adjusting portion 40 for adjusting the height of the crimped portion 31 will be described.

[0039] As described above, during modularization, the positive and negative external terminals of multiple batteries are welded to external leads. Because the external leads are welded, the smaller the variation in height of the crimping portion 31 between individual batteries, the better. Therefore, the height adjustment portion 40 must not deform when crimped to the crimping portion 31. If the height adjustment portion 40 were made of resin, it would be compressed by the crimping pressure and its height would be unstable. Furthermore, to align the heights of the positive and negative external terminals, the height adjustment portion 40 must shrink and expand to the same extent as the positive cap 27 due to changes in ambient temperature. To meet these requirements, the height adjustment portion 40 must be made of metal. It may also be made of the same material as the positive cap 27 or the rupture disk 24.

[0040] Furthermore, as described above, when the flange 27a is connected to the rupture disk 24 by welding, a bulge occurs on the flange 27a at the welded portion 50. In order to absorb the bulge of the welded portion 50 when the flange 27a is crimped, the height adjusting portion 40 is preferably made of aluminum.

[0041] The height adjustment portion 40 of this embodiment is formed as a separate body from the rupture disk 24 and the flange 27a. As described below, the height adjustment portion 40 may be formed by bending the rupture disk 24 or the flange 27a radially inward. However, there are various electrode height requirements, including not only the requirement that the positive electrode external terminal and the negative electrode external terminal be at the same height, but also the requirement that the height of the crimping portion 31 be higher than the height of the positive electrode cap 27. In order to meet various electrode height requirements, providing a separate height adjustment portion 40 makes design easier.

[0042] Furthermore, when considering connecting an external lead to the crimped portion 31, if the crimped portion 31 is curved, the connection area of ​​the external lead will be small, which may result in an incomplete connection. To increase the connection area, the top surface of the crimped portion 31 is preferably formed flat. In this embodiment, the top surface of the crimped portion 31 is formed to extend flat in the inner diameter direction. To maintain the flat top surface of the crimped portion 31, the inner diameter end of the height adjustment portion 40 is formed to protrude radially inward beyond the tip of the crimped portion 31. Similarly, the inner diameter end of the bent portion 24c of the rupture disk 24 is formed to protrude radially inward beyond the tip of the crimped portion 31. This configuration prevents the tip of the crimped portion 31 from tilting toward the sealing body 17, allowing the top surface to be formed flat.

[0043] (Second embodiment) 3 is an enlarged cross-sectional view of the periphery of the crimped portion of the nonaqueous electrolyte secondary battery according to the second embodiment of the present disclosure. The sealing body 17 of this embodiment differs from the first embodiment in that the bent portion 24c of the rupture disk 24 is eliminated, the height of the upstanding portion 24a is set to be equal to or less than the thickness of the flange 27a, and only the metal spacer 40 is provided on the flange 27a.

[0044] The assembly process for the sealing body 17 of this embodiment does not include the process of crimping the metal spacer 40 at the bent portion 24c of the rupture disk 24 (assembly process 8 for the sealing body 17 in embodiment 1). There are no limitations on the method for fixing the metal spacer 40, but it may be fixed to the flange 27a at several locations with an adhesive. Alternatively, the metal spacer 40 and the flange 27a may be welded together.

[0045] In this embodiment, since there is no bent portion 24c of the rupture disk 24, a thicker metal spacer 40 is required compared to the first embodiment. On the other hand, bending the rupture disk 24 in the inner diameter direction is not required.

[0046] As in the first embodiment, the requirement to form a flat top surface of crimping portion 31 to stabilize the connection of the external lead is met. That is, in this embodiment as well, the tip of metal spacer 40 in the inner diameter direction is formed to protrude radially inward beyond the tip of crimping portion 31. Because it is formed in this manner, the tip of crimping portion 31 is prevented from tilting toward sealing body 17, and the top surface can be formed flat.

[0047] (Third embodiment) 4 is an enlarged cross-sectional view of the periphery of the crimped portion of the non-aqueous electrolyte secondary battery according to the third embodiment of the present disclosure. In this embodiment, the height adjusting portion 40 is realized by bending the peripheral portion of the rupture disk 24 in the inner diameter direction.

[0048] In this embodiment, the rupture disk 24 before assembling the sealing body 17 has a peripheral upright portion 24a that is longer than the upright portion 24a of the first embodiment. With the positive electrode cap 27 inserted into the upright portion 24a, the length of the upright portion 24a that protrudes above the flange 27a is about twice the length in the inner diameter direction after the upright portion 24a is bent after assembling the sealing body 17.

[0049] The sealing body 17 is formed as follows. The rising portion 24a is bent inward at half the length of the portion that protrudes above the flange 27a. Then, the folded portion is crimped radially inward, so as to sandwich the flange 27a. In this embodiment, the bent portion of the rupture disk 24 that contacts the flange 27a becomes the height adjustment portion 40. The number of times that the rising portion 24a of the rupture disk 24 is bent is not limited to the configuration shown in FIG. 4. It can be appropriately changed according to the height of the crimping portion 31 and the thickness of the rupture disk 24.

[0050] 5 shows another embodiment. In this embodiment, the end of the upright portion 24a of the rupture disk 24 is bent radially outward and then bent radially inward to form a height adjustment portion 40.

[0051] (Other embodiments) The method for forming the height adjustment portion 40 is not limited to the above-described embodiment. For example, as shown in Fig. 6, the height adjustment portion 40 may be formed by bending the peripheral edge of the flange 27a of the positive electrode cap 27 radially inward. [Explanation of symbols]

[0052] 10 non-aqueous electrolyte secondary battery, 11 positive electrode, 12 negative electrode, 13 separator, 14 electrode body, 16 outer can, 17 sealing body, 18 insulating plate, 19 insulating plate, 20 positive electrode lead, 21 negative electrode lead, 23 terminal plate, 24 rupture disk, 24a standing portion, 24b protrusion portion, 24c folded portion, 26 insulating plate, 26a standing portion, 27 positive electrode cap, 27a flange, 28 gasket, 30 bottomed cylindrical portion, 31 crimping portion, 32 grooved portion, 33 bottom, 40 height adjustment portion (metal spacer), 50 welded portion

Claims

1. a cylindrical outer can with a bottom that houses the electrode assembly; a sealing body that closes the opening of the outer can; Equipped with The outer can has a crimping portion formed by bending an end of the opening inward in the radial direction and crimping and fixing the sealing body, The sealing body includes a rupture disk, a positive electrode cap having a flange, and a metal height adjustment part for adjusting the height of the crimping part; and The height adjustment portion is a metal spacer that is disposed between the upper surface of the flange of the positive electrode cap and the gasket.

2. A cylindrical outer can with a bottom that houses an electrode body; a sealing body that closes the opening of the outer can; Equipped with the outer can has a crimping portion formed by bending an end of the opening inward in the radial direction and crimping and fixing the sealing body via a gasket; The sealing body includes a rupture disk, a positive electrode cap having a flange, and a metal height adjustment part for adjusting the height of the crimping part; and A sealed battery, wherein the height adjustment portion is formed by bending the peripheral portion of the rupture disk radially inward.

3. A cylindrical outer can with a bottom that houses an electrode body; a sealing body that closes the opening of the outer can; Equipped with the outer can has a crimping portion formed by bending an end of the opening inward in the radial direction and crimping and fixing the sealing body via a gasket; The sealing body includes a rupture disk, a positive electrode cap having a flange, and a metal height adjustment part for adjusting the height of the crimping part; and The height adjustment portion is formed by bending a peripheral edge portion of the flange of the positive electrode cap radially inward.

4. The metal spacer is welded or glued to the flange. The sealed battery according to claim 1 .

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