Cylindrical battery

Abstract

This battery (10) comprises: an electrode body (14) in which a positive electrode (11) and a negative electrode (12) are wound via a separator (13); an outer can (20) that has a cylindrical part (20A) including a groove part (28) recessed inward in the radial direction over the entire circumference in the circumferential direction, and houses the electrode body (14); and a sealing body (19) that is crimped and fixed to the opening of the outer can (20) via a gasket (24). The sealing body (19) has a movement suppression part that suppresses movement of the gasket (24).

Description

Cylindrical battery

[0001] The present disclosure relates to cylindrical batteries.

[0002] A conventional cylindrical battery is described in Patent Document 1. This cylindrical battery includes an electrode assembly, a cylindrical outer can with a bottom that houses the electrode assembly, a sealing body that closes the opening of the outer can, and a gasket sandwiched between the outer can and the sealing body. The cylindrical portion of the outer can has a grooved portion and an annular shoulder portion. The grooved portion is formed by recessing a portion of the cylindrical portion radially inward. The shoulder portion is formed when the tip of the opening side of the cylindrical portion is bent inward and crimped onto the peripheral edge of the sealing body, and extends radially inward. The sealing body is crimped and fixed to the outer can by being sandwiched between the shoulder portion and the grooved portion via the gasket.

[0003] Japanese Patent Application Publication No. 09-274923

[0004] During the crimping process, the gasket moves downward from the tip of the outer can due to the force exerted by the bottom of the outer can, and moves radially inward between the grooved portion and the sealing body. The present inventors discovered that this movement of the gasket easily creates gaps around the corners of the outer can on the sealing body side of the grooved portion, making it easy for electrolyte to enter these gaps due to capillary action or the like. In this context, if electrolyte enters these gaps, the electrolyte may remain in the gaps and become a breeding ground for corrosion. Therefore, an object of the present disclosure is to provide a cylindrical battery that is less likely to create gaps around the corners of the outer can on the sealing body side of the grooved portion, making it less susceptible to corrosion.

[0005] In order to solve the above problems, the cylindrical battery of the present disclosure comprises an electrode body in which a positive electrode and a negative electrode are wound with a separator interposed therebetween, an outer can having a tubular portion including a grooved portion recessed radially inward around the entire circumferential direction and housing the electrode body, and a sealing body that is crimped and fixed to the opening of the outer can via a gasket, and the sealing body has a movement suppression portion that suppresses movement of the gasket.

[0006] In the cylindrical battery according to the present disclosure, gaps are unlikely to form at the corners of the grooved portion of the outer can that are on the sealing body side and on the outer periphery side, and corrosion is unlikely to occur.

[0007] Fig. 1 is an axial cross-sectional view of a cylindrical battery according to an embodiment of the present disclosure; Fig. 2 is an enlarged cross-sectional view of the periphery of a grooved portion in Fig. 1; Fig. 3 is an enlarged cross-sectional view of a cylindrical battery of a reference example corresponding to Fig. 2; Fig. 4 is an enlarged cross-sectional view of a cylindrical battery of a first modified example corresponding to Fig. 2; Fig. 5 is an enlarged cross-sectional view of a cylindrical battery of a second modified example corresponding to Fig. 2; Fig. 6 is an enlarged cross-sectional view of a cylindrical battery of a third modified example corresponding to Fig. 2;

[0008] Hereinafter, an embodiment of a cylindrical battery according to the present disclosure will be described in detail with reference to the drawings. The cylindrical battery according to the present disclosure may be a primary battery or a secondary battery. It may also be a battery using an aqueous electrolyte or a battery using a non-aqueous electrolyte. Hereinafter, a lithium-ion secondary battery will be exemplified as a cylindrical battery 10 according to one embodiment, but the cylindrical battery according to the present disclosure is not limited thereto.

[0009] It is anticipated from the beginning that new embodiments may be constructed by appropriately combining the features of the embodiments and variations described below. In the following embodiments, the same components are designated by the same reference numerals in the drawings, and redundant explanations are omitted. Furthermore, multiple drawings include schematic diagrams, and the dimensional ratios of the length, width, height, and other dimensions of each component do not necessarily match between different drawings. In this specification, the sealing body 19 side in the axial (height) direction of the cylindrical battery 10 is referred to as "upper," and the bottom 20A side of the outer can 20 in the axial direction is referred to as "lower." Furthermore, among the components described below, components not recited in the independent claims representing the highest concept are optional components and not essential components. Furthermore, the present disclosure is not limited to the following embodiments and their variations, and various improvements and modifications are possible within the scope of the claims of this application and their equivalents.

[0010] Fig. 1 is an axial cross-sectional view of a cylindrical battery 10 according to one embodiment of the present disclosure. As shown in Fig. 1, the cylindrical battery (hereinafter simply referred to as battery) 10 includes an electrode assembly 14, a non-aqueous electrolyte, a cylindrical outer can 20 with a bottom that houses the electrode assembly 14 and the non-aqueous electrolyte, and a sealing body 19 that closes the opening of the outer can 20 via an annular gasket 24.

[0011] The electrode assembly 14 includes a long positive electrode 11, a long negative electrode 12, and two long separators 13 interposed between the positive electrode 11 and the negative electrode 12, and has a wound structure in which the positive electrode 11 and the negative electrode 12 are wound with the separators 13 interposed therebetween. The negative electrode 12 is formed to be slightly larger than the positive electrode 11 in order to prevent lithium deposition. The negative electrode 12 is formed to be longer than the positive electrode 11 in the winding direction and the axial direction. The two separators 13 are formed to be slightly larger than the positive electrode 11 and are arranged to sandwich the positive electrode 11. The separators 13 protrude above and below the positive electrode 11 and the negative electrode 12.

[0012] The non-aqueous electrolyte has ion conductivity (e.g., lithium ion conductivity). The non-aqueous electrolyte may be a liquid electrolyte (electrolytic solution) or a solid electrolyte. The liquid electrolyte (electrolytic solution) 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 mixed solvents of two or more of these. Examples of the non-aqueous solvent include ethylene carbonate (EC), ethyl methyl carbonate (EMC), dimethyl carbonate (DMC), diethyl carbonate (DEC), and mixed solvents of these. The non-aqueous solvent may contain a halogen-substituted compound (e.g., fluoroethylene carbonate) in which at least a portion of the hydrogen atoms of these solvents are substituted with halogen atoms such as fluorine. The electrolyte salt may include, for example, LiPF ６ Lithium salts such as

[0013] Examples of the solid electrolyte include solid or gel polymer electrolytes and inorganic solid electrolytes. The polymer electrolyte includes, for example, a lithium salt and a matrix polymer, or a non-aqueous solvent, a lithium salt, and a matrix polymer. Examples of the matrix polymer include a polymer material that absorbs the non-aqueous solvent and gels. Examples of the polymer material include fluororesin, acrylic resin, and polyether resin. Examples of the inorganic solid electrolyte include materials known in all-solid-state lithium ion secondary batteries (e.g., oxide-based solid electrolytes, sulfide-based solid electrolytes, halide-based solid electrolytes, etc.).

[0014] The positive electrode 11 has a positive electrode core and positive electrode mixture layers formed on both sides of the positive electrode core. The positive electrode core can be made of a metal foil, 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 is 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 core, drying the coating, and then compressing it to form positive electrode mixture layers on both sides of the positive electrode core.

[0015] 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.

[0016] Examples of conductive agents contained in the positive electrode mixture layer include carbon black such as acetylene black and ketjen black, and carbon materials such as graphite. Examples of binders contained in the positive electrode mixture layer include fluororesins such as polytetrafluoroethylene (PTFE) and polyvinylidene fluoride (PVdF), polyacrylonitrile (PAN), polyimide resins, acrylic resins, and polyolefin resins. These resins may be used in combination with cellulose derivatives such as carboxymethyl cellulose (CMC) or its salts, polyethylene oxide (PEO), and the like.

[0017] The negative electrode 12 has a negative electrode core and negative electrode mixture layers formed on both sides of the negative electrode core. The negative electrode core can be made of a metal foil, 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 is produced, for example, by applying a negative electrode mixture slurry containing the negative electrode active material and the binder onto the negative electrode core, drying the coating, and then compressing it to form a negative electrode mixture layer on both sides of the negative electrode core.

[0018] The negative electrode active material generally uses a carbon material that reversibly absorbs and releases lithium ions. Preferred carbon materials are graphites such as 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 silicon (Si) material as the negative electrode active material. In addition, the negative electrode active material may be a metal other than Si that alloys with lithium, an alloy containing such a metal, or a compound containing such a metal.

[0019] As in the case of the positive electrode 11, fluororesin, PAN, polyimide resin, acrylic resin, polyolefin resin, or the like may be used as the binder contained in the negative electrode mixture layer, but styrene-butadiene rubber (SBR) or a modified product thereof is preferably used. In addition to SBR or the like, the negative electrode mixture layer may also contain, for example, CMC or a salt thereof, polyacrylic acid (PAA) or a salt thereof, polyvinyl alcohol, or the like.

[0020] A porous sheet having ion permeability and insulating properties is used for the separator 13. 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 polyolefin 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.

[0021] An upper insulating plate 15 is disposed above the electrode body 14, and a lower insulating plate 16 is disposed below the electrode body 14. In the example shown in FIG. 1 , a positive electrode lead 17 attached to the positive electrode 11 passes through a through hole in the upper insulating plate 15, extends toward the sealing body 19, and is connected to the underside of the sealing body 19 by welding or the like. On the other hand, a negative electrode lead 18 attached to the negative electrode 12 passes outside the lower insulating plate 16, extends toward the bottom 20A of the outer can 20, and is connected to the inner surface of the bottom 20A by welding or the like. The sealing body 19 to which the positive electrode lead 17 is connected serves as a positive electrode terminal, and the outer can 20 to which the negative electrode lead 18 is connected serves as a negative electrode terminal.

[0022] A gasket 24 is provided between the outer can 20 and the sealing body 19 to ensure sealing of the battery interior and insulation between the outer can 20 and the sealing body 19. The outer can 20 has a cylindrical portion 20B and a bottom portion 20A. The cylindrical portion 20B includes an annular grooved portion 28 and an annular shoulder portion 29. The grooved portion 28 is formed by spinning a portion of the cylindrical portion 20B to recess it radially inward. The shoulder portion 29, on the other hand, is formed when the upper end of the cylindrical portion 20B is bent radially inward and crimped to a flange portion (peripheral portion) 31 of the sealing body 19, and extends radially inward. The crimping causes the sealing body 19 to be sandwiched between the shoulder portion 29 and the grooved portion 28 via the gasket 24, and the sealing body 19 is fixed to the outer can 20.

[0023] The sealing body 19 is a disk-shaped member equipped with a current interruption mechanism. The sealing body 19 has a structure in which, in order from the electrode body 14 side, an internal terminal plate 21, an insulating plate 23, and a rupture plate 22 are stacked. The rupture plate 22 forms a valve body and is disposed opposite the internal terminal plate 21 with the insulating plate 23 sandwiched therebetween. An opening 23A is formed in the radial center of the insulating plate 23, and an air vent 23B is formed in a portion overlapping with the air vent 21C of the internal terminal plate 21.

[0024] The rupture plate 22 has a valve portion 22A at its radial center that ruptures when the battery internal pressure exceeds a predetermined threshold, and the valve portion 22A is connected by welding or the like to a central portion 21B of the internal terminal plate 21 through an opening 23A in the insulating plate 23. The valve portion 22A includes a lower convex portion that is convex toward the inside of the battery and is provided in the radial center, and a thin portion formed around the lower convex portion. The thickness of the thin portion becomes thinner as it goes radially outward.

[0025] The internal terminal plate 21 is a metal plate and includes a thick annular portion 21A to which the positive electrode lead 17 is connected, and a disk-shaped central portion 21B that is connected to the radially inner end of the annular portion 21A and is thinner than the annular portion 21A. An air vent 21C is formed in the annular portion 21A. The positive electrode lead 17 is connected to the underside of the annular portion 21A. The internal terminal plate 21 to which the positive electrode lead 17 is connected is electrically connected to the rupture plate 22, thereby forming a current path connecting the electrode body 14 to the rupture plate 22.

[0026] When the internal pressure of the battery 10 increases, the valve portion 22A inverts so as to become convex axially upward, using the annular end portion 22B, which is the radially outer, less rigid, thin-walled portion as a fulcrum. Simultaneously with this inversion, the central portion 21B is separated from the annular portion 21A or disengages from the valve portion 22A. Because the valve portion 22A is insulated from the annular portion 21A by the insulating plate 23, this inversion interrupts the current path. If the internal pressure of the battery further increases, the annular end portion 22B of the thin-walled portion breaks, forming a gas outlet.

[0027] The structure of sealing body 19 is not limited to the structure shown in Fig. 1. For example, sealing body 19 may be composed of only a rupture plate. Alternatively, sealing body 19 may have a laminated structure including two rupture plates, and the laminated structure may have a convex portion that protrudes upward in the radial center and a terminal cap that covers the rupture plate.

[0028] 2 is an enlarged cross-sectional view of the periphery of the grooved portion 28 in FIG. 1 . As shown in FIGS. 1 and 2 , the sealing body 19 has a movement suppression portion that suppresses movement of the gasket 24, and in this embodiment, the rupture plate 22 constituting the valve body has the movement suppression portion. More specifically, the lower surface of the sealing body 19 (rupture plate 22) on the electrode body 14 side has one or more protrusions 33 that protrude toward the electrode body 14 and contact the gasket 24, and the movement suppression portion includes one or more protrusions 33. In this embodiment, the outer peripheral end of the sealing body 19 is composed of a valve body made of a single member (rupture plate 22), but the outer peripheral end of the sealing body 19 may also be composed of a valve body including multiple members.

[0029] In this embodiment, the one or more protrusions 33 are configured as a single annular protrusion that exists around the entire circumferential circumference. The protrusion 33 is located radially inward from the radial inner end 28a of the grooved portion 28. The gasket 24 contacts the outer peripheral surface of the protrusion 33, and receives a radially outward force from the protrusion 33. Within the axial extent of the protrusion 33, the gasket 24 is located radially outward from the protrusion 33.

[0030] Next, the effects obtained by providing the protrusion 33 that protrudes downward on the underside of the sealing body 19 will be described. Fig. 3 is an enlarged cross section of a battery 410 of a reference example corresponding to Fig. 2. Battery 410 differs from battery 10 in that it does not have protrusion 33. Referring to Fig. 3, when the front end of the outer can 20 is crimped, gasket 24 receives a downward force from the front end and moves downward, and moves radially inward as indicated by arrow B between groove 28 and sealing body 419.

[0031] The present inventors have found that this movement of the gasket 24 tends to create gaps R around the corners of the grooved portion 28 of the outer can 20 on the sealing body 19 side and on the outer periphery, and that electrolytes tend to enter the gaps R due to capillary action or the like. In this context, if the electrolyte enters the gaps R, there is a risk that the electrolyte will remain in the gaps and become a breeding ground for corrosion.

[0032] In contrast, in battery 10 of the present disclosure, the underside of sealing body 19 has protruding portion 33 that protrudes toward electrode body 14 and contacts gasket 24. Therefore, gasket 24 is less likely to move downward due to the frictional force received from protruding portion 33, and radial inward movement of gasket 24, as indicated by arrow A, between grooved portion 28 and sealing body 19 is suppressed when the leading end of outer can 20 is crimped (hereinafter simply referred to as "crimping"). Therefore, gaps are less likely to occur around the corners of grooved portion 28 on the sealing body 19 side and on the outer periphery during crimping, thereby suppressing corrosion around those corners.

[0033] If the protrusion 33 is an annular protrusion that exists around the entire circumference in the circumferential direction, frictional force is applied to the gasket 24 from the protrusion 33 over the entire circumferential direction, thereby effectively preventing downward movement of the gasket 24. In order to effectively prevent downward movement of the gasket 24, when the axial distance between the radial outer end 19a (see FIG. 2) of the surface of the sealing body 19 that faces the electrode body 14 in the axial direction and the grooved portion 28 is L (see FIG. 2), the axial height of the protrusion 33 is preferably 0.5L or more.

[0034] The axial height of the protruding portion 33 is preferably 4 / 5L or less, and more preferably 3 / 4L or less, because this makes it difficult for excessive force to be applied to the gasket 24 and tends to improve the durability of the gasket 24. It is preferable that the tip of the protruding portion 33 be located closer to the sealing body 19 in the axial direction than the grooved portion 28, because this makes it possible to improve the insulation. It is preferable that the gasket 24 have an opposing portion 24a that radially faces the inner end 28a of the grooved portion 28, because this makes it possible to achieve good insulation.

[0035] The present disclosure is not limited to the above-described embodiment and its modifications, and various improvements and modifications are possible within the scope of the claims of the present application and their equivalents. For example, in the above-described embodiment, the gasket 24 is located radially outward of the protrusion 33 within the axial extent of the protrusion 33. However, as shown in Figure 4, i.e., the enlarged cross-sectional view of the battery 110 of the first modification corresponding to Figure 2, the gasket 124 may be configured to contact substantially the entire outer surface of the annular protrusion 133.

[0036] For example, if the annular protrusion 33 has a generally rectangular shape in the cross section shown in the figure, the gasket 124 may be configured to contact not only the outer peripheral surface 33a of the annular protrusion 33, but also the inner peripheral surface 33b and the axial tip surface 33c. According to the battery 110 of the first modification, the frictional force applied to the gasket 124 by the protrusion 33 can be increased, thereby more effectively preventing downward movement of the gasket 124 during crimping.

[0037] As shown in Figure 5, an enlarged cross-sectional view of a battery 210 of a second modified example corresponding to Figure 2, the underside of the sealing body 219 (rupture plate 222) may have multiple annular protrusions 233 protruding toward the electrode body 14, and the multiple protrusions 233 may be arranged adjacent to each other or spaced apart in the radial direction. Each protrusion 233 may be configured so that substantially the entire outer surface, or at least the outer peripheral surface, contacts the gasket 224. This effectively prevents the gasket 124 from moving downward during crimping.

[0038] The above description deals with the case where protrusion 133 is an annular protrusion that exists around the entire circumferential circumference. However, protrusion 133 does not have to exist around the entire circumferential circumference. For example, protrusion 133 may have an arc shape in a plan view from the axially lower side. In this case, the sealing body preferably has, in a plan view from the axially lower side, multiple arc-shaped protrusions that are spaced apart in the circumferential direction on a concentric circle centered on the sealing body center, and more preferably multiple substantially identical arc-shaped protrusions that are spaced apart in the circumferential direction on the concentric circle. Furthermore, when the sealing body has one or more protrusions, the one or more protrusions may include at least one annular protrusion.

[0039] Regardless of whether the protrusion 33, 233 is annular or not, the shape of the protrusion 33, 233 in the axial cross section of the battery 10, 110, 210 may be rectangular as shown in Figures 2 and 4, triangular as shown in Figure 5, or any other polygonal shape, such as circular or elliptical. If at least one protrusion 33, 233 in the axial cross section of the battery 10, 110, 210 has a radially outer surface that extends approximately parallel to the axial direction or has a radially outer surface that displaces radially outward as it extends axially downward, the ability to prevent downward movement of the gasket 24, 124, 224 during crimping can be improved.

[0040] Although the protrusion 33 is described as being located radially inward from the inner end 28a of the grooved portion 28, the battery may also include a protrusion located radially outward from the radial inner end of the grooved portion. Furthermore, as shown in Figure 6, i.e., an enlarged cross-sectional view of a battery 310 according to a third modification corresponding to Figure 2, the surface of the sealing body 319 (rupture plate 322) facing the electrode body may have multiple protrusions 333 arranged approximately evenly in the circumferential and radial directions, and in this case, each protrusion 333 may have a central axis extending approximately parallel to the axial direction. For example, the surface of the sealing body 319 facing the electrode body 14 may have a number of small protrusions.

[0041] The above description also covers the case where the protrusion 33, 233, 333 is present on the rupture plate 22, 222, 322. However, the protrusion may be present on the lowest component of the sealing body. For example, if the sealing body has a laminated structure in which a terminal plate to which an electrode lead is joined, a lower valve body, an insulating plate, an upper valve body, and a terminal cap are stacked axially from the bottom, one or more protrusions protruding downward may be provided on the lower surface of the terminal plate. Furthermore, in the battery disclosed herein, the sealing body may have a movement suppressing portion that suppresses movement of the gasket. The movement suppressing portion may include one or more protrusions provided on the outer peripheral surface of the sealing body, protruding radially outward, and contacting the gasket. Furthermore, the movement suppressing portion may include one or more protrusions provided on the upper surface of the sealing body, protruding axially upward, and contacting the gasket.

[0042] The cylindrical battery of the present disclosure may also have the following configurations. Configuration 1: The cylindrical battery includes an electrode assembly in which a positive electrode and a negative electrode are wound with a separator interposed therebetween, an outer can having a tubular portion including a grooved portion recessed radially inward around the entire circumferential direction and housing the electrode assembly, and a sealing body that is crimped and fixed to an opening of the outer can via a gasket, the sealing body having a movement suppressing portion that suppresses movement of the gasket. Configuration 2: The cylindrical battery according to Configuration 1, in which an outer peripheral end of the sealing body is formed by a valve body, and the valve body has the movement suppressing portion. Configuration 3: The cylindrical battery according to Configuration 1 or 2, in which a surface of the sealing body facing the electrode assembly has one or more protrusions that protrude toward the electrode assembly and contact the gasket, and the movement suppressing portion includes the one or more protrusions. Configuration 4: The cylindrical battery according to any one of Configurations 1 to 3, wherein the axial height of the protrusion is 0.5L or more, where L is the axial distance between the radial outer end of the sealing body's surface facing the electrode body in the axial direction and the grooved portion.Configuration 5: The cylindrical battery according to any one of Configurations 1 to 4, wherein the tip of the protrusion is located closer to the sealing body in the axial direction than the grooved portion.Configuration 6: The cylindrical battery according to any one of Configurations 1 to 5, wherein the one or more protrusions include an annular protrusion that exists around the entire circumferential circumference.Configuration 7: The cylindrical battery according to any one of Configurations 1 to 5, wherein the sealing body's surface facing the electrode body has a plurality of protrusions that are approximately evenly arranged in the circumferential and radial directions.Configuration 8: The cylindrical battery according to any one of Configurations 1 to 7, wherein the gasket has an opposing portion that faces the radial inner end of the grooved portion in the radial direction.

[0043] 10,110,210,310 Battery, 11 Positive electrode, 12 Negative electrode, 13 Separator, 14 Electrode body, 15 Upper insulating plate, 16 Lower insulating plate, 17 Positive electrode lead, 18 Negative electrode lead, 19,219,319 Sealing body, 19a Radial outer end of lower surface of sealing body, 20 Outer can, 20A Bottom, 20B Cylindrical portion, 21 Internal terminal plate, 21A Annular portion, 21B Central portion, 21C Vent, 22,222,322 Rupture plate, 22A Valve portion, 23,233 Insulating plate, 23A Opening, 23B Vent, 24,124,224 Gasket, 24a Opposing portion, 28 Grooved portion, 28a: radial inner end of grooved portion, 29: shoulder portion, 33, 233, 333: protruding portion, 133a: outer peripheral surface of protruding portion, 133b: inner peripheral surface of protruding portion, 133c: tip surface of protruding portion, R: gap.

Claims

1. A cylindrical battery comprising: an electrode assembly in which a positive electrode and a negative electrode are wound with a separator interposed therebetween; an outer can having a cylindrical portion including a grooved portion recessed radially inward around the entire circumferential direction and housing the electrode assembly; and a sealing body that is crimped and fixed to the opening of the outer can via a gasket, wherein the sealing body has a movement suppression portion that suppresses movement of the gasket.

2. The cylindrical battery according to claim 1, wherein the outer peripheral end of the sealing body is formed by a valve body, and the valve body has the movement suppression portion.

3. A cylindrical battery as described in claim 1, wherein the surface of the sealing body facing the electrode body has one or more protrusions that protrude toward the electrode body and contact the gasket, and the movement suppression portion includes the one or more protrusions.

4. A cylindrical battery as described in claim 3, wherein the axial distance between the radial outer end of the surface of the sealing body facing the electrode body in the axial direction and the grooved portion is L, and the axial height of the protrusion is 0.5L or more.

5. The cylindrical battery according to claim 3, wherein the tip of the protrusion is located closer to the sealing body in the axial direction than the groove.

6. The cylindrical battery according to claim 3, wherein the one or more protrusions include an annular protrusion that exists around the entire circumferential circumference.

7. The cylindrical battery according to claim 3, wherein the surface of the sealing body facing the electrode body has a plurality of the protrusions arranged approximately uniformly in the circumferential and radial directions.

8. A cylindrical battery according to any one of claims 1 to 7, wherein the gasket has opposing portions that face radially at inner ends of the grooved portions in the radial direction.

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