Cylindrical battery

Abstract

The battery (10) comprises: an electrode body (14) formed by winding a positive electrode (11) and a negative electrode (12) through a separator (13); an outer can (20) having a cylindrical portion (20B) including a slotted portion (28) and accommodating the electrode body (14), the slotted portion (28) being recessed radially inward throughout the entire circumference; a sealing body (19) riveted to the opening of the outer can (20) through a gasket (24); and one or more pressing members (33) located between the slotted portion (28) and the sealing body (19) in the axial direction, pressing the gasket (24) toward the sealing body (19).

Description

Technical Field

[0001] This disclosure relates to cylindrical batteries. Background Technology

[0002] Conventionally, a cylindrical battery as described in Patent Document 1 exists. This cylindrical battery includes an electrode body, a bottomed cylindrical outer can containing the electrode body, a sealing body sealing the opening of the outer can, and a gasket held between the outer can and the sealing body. The cylindrical portion of the outer can has a slotted portion and an annular shoulder. The slotted portion is formed by recessing a portion of the cylindrical portion radially inward. The shoulder is formed by bending the front end of the opening side of the cylindrical portion inward and riveting it to the periphery of the sealing body, and extends radially inward. The sealing body is held between the shoulder and the slotted portion and the gasket by riveting, thereby being fixed to the outer can.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 09-274923 Summary of the Invention

[0006] With a thicker flange on the outer periphery of the sealing body, the strength of the sealing body increases, effectively suppressing deformation when riveting the front end of the opening side of the outer can, and facilitating high-precision positioning of the sealing body. Therefore, for example, when modularizing multiple batteries by electrical connection, the welding position of the sealing body can be easily positioned with high precision, enabling smooth modularization.

[0007] However, in this case, it is difficult to reduce the volume of the upper part of the electrode body in the battery, thus making it difficult to achieve high battery capacity. On the other hand, if the thickness of the sealing body is reduced in order to achieve high battery capacity, the sealing body is prone to deformation when riveting the front end of the opening side of the outer packaging can, making it difficult to accurately position the welding position of the sealing body and hindering modularization. Therefore, the object of this disclosure is to provide a cylindrical battery that is easy to achieve high capacity and whose sealing body is also difficult to deform.

[0008] To address the aforementioned problems, the cylindrical battery disclosed herein comprises: an electrode body formed by winding a positive electrode and a negative electrode together with a separator; an outer can having a cylindrical portion including a slotted portion and accommodating the electrode body, the slotted portion being recessed radially inward throughout the entire circumference; a sealing body riveted to the opening of the outer can with a sealing member; and one or more pressing members located between the slotted portion and the sealing body in the axial direction, pressing the sealing member toward the sealing body.

[0009] The cylindrical battery disclosed herein is easy to achieve high capacity, and the sealing body is also difficult to deform. Attached Figure Description

[0010] Figure 1 This is an axial cross-sectional view of a cylindrical battery according to one embodiment of the present disclosure.

[0011] Figure 2 yes Figure 1 An enlarged sectional view of the upper side of the slotted portion.

[0012] Figure 3 This is a three-dimensional view of the outer can and pressing components cut along the axial direction from an oblique top, and it is an enlarged three-dimensional view of the perimeter of the slotted part.

[0013] Figure 4 The cylindrical battery in the reference example is... Figure 3 The corresponding enlarged cross-sectional view.

[0014] Figure 5 It is the cylindrical battery in the first modified example and Figure 3 The corresponding 3D image.

[0015] Figure 6 It is the cylindrical battery in the second variation example with Figure 3 Corresponding 3D image Detailed Implementation

[0016] Hereinafter, embodiments of the cylindrical battery according to this disclosure will be described in detail with reference to the accompanying drawings. Furthermore, the cylindrical battery of this disclosure can be a primary battery or a secondary battery. Additionally, it can be a battery using an aqueous electrolyte or a battery using a non-aqueous electrolyte. Hereinafter, a cylindrical battery 10 as an embodiment is exemplified as a lithium-ion secondary battery, but the cylindrical battery of this disclosure is not limited to this.

[0017] From the outset, it was envisioned that new embodiments could be constructed by appropriately combining the characteristic features of the following described embodiments and variations. In the following embodiments, the same reference numerals are used for the same structures in the drawings, and repeated descriptions are omitted. Furthermore, multiple drawings include schematic diagrams, and the dimensional ratios of the components (longitudinal, transverse, height, etc.) may not be consistent between different drawings. In this specification, the axial (height direction) sealing body 19 side of the cylindrical battery 10 is referred to as "upper," and the axial bottom 20A side of the outer can 20 is referred to as "lower." Additionally, structural elements described below that are not described in the independent claims representing the highest-level concept are arbitrary structural elements, not essential ones. Furthermore, this disclosure is not limited to the following embodiments and variations, and various modifications and alterations can be made within the scope of the claims and their equivalents.

[0018] Figure 1 This is an axial cross-sectional view of a cylindrical battery 10 according to one embodiment of this disclosure. Figure 1 As shown, the cylindrical battery (hereinafter referred to as the battery) 10 includes an electrode body 14, a non-aqueous electrolyte, a bottomed cylindrical outer can 20 that contains the electrode body 14 and the non-aqueous electrolyte, and a sealing body 19 that seals the opening of the outer can 20 through an annular gasket 24 that constitutes a sealing member.

[0019] The electrode body 14 includes an elongated positive electrode 11, an elongated negative electrode 12, and two elongated spacers 13 between the positive electrode 11 and the negative electrode 12, having a wound structure in which the positive electrode 11 and the negative electrode 12 are wound together with the spacers 13 in between. To prevent lithium deposition, the negative electrode 12 is formed to be one size larger than the positive electrode 11. The negative electrode 12 is longer than the positive electrode 11 in the winding direction and axial direction. The two spacers 13 are formed to be one size larger than the positive electrode 11 and are configured to sandwich the positive electrode 11. The spacers 13 protrude upwards and downwards from the positive electrode 11 and the negative electrode 12.

[0020] Non-aqueous electrolytes possess ionic conductivity (e.g., lithium-ion conductivity). Non-aqueous electrolytes can be liquid electrolytes (electrolytes) or solid electrolytes. Liquid electrolytes (electrolytes) comprise a non-aqueous solvent and an electrolyte salt dissolved in the non-aqueous solvent. Examples of non-aqueous solvents include esters, ethers, nitriles, amides, and mixtures of two or more of these. Examples of non-aqueous solvents include ethylene carbonate (EC), ethyl methyl carbonate (EMC), dimethyl carbonate (DMC), diethyl carbonate (DEC), and mixtures thereof. Non-aqueous solvents may also contain halogen substitutes (e.g., fluoroethylene carbonate) in which at least a portion of the hydrogen atoms of these solvents are replaced by halogen atoms such as fluorine. For the electrolyte salt, lithium salts such as LiPF6 are used, for example.

[0021] As solid electrolytes, examples include solid or gel-like polymer electrolytes and inorganic solid electrolytes. Polymer electrolytes, for example, contain lithium salts and a matrix polymer, or contain non-aqueous solvents, lithium salts, and a matrix polymer. As a matrix polymer, for example, a polymer material that gels by absorbing non-aqueous solvents is used. As a polymer material, for example, fluoropolymers, acrylic resins, polyether resins, etc., are used. As inorganic solid electrolytes, for example, 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.) are used.

[0022] The positive electrode 11 has a positive electrode core and positive electrode additive layers formed on both sides of the positive electrode core. For the positive electrode core, a metal foil stable within the potential range of the positive electrode 11, such as aluminum or an aluminum alloy, or a thin film with the metal disposed on the surface, can be used. The positive electrode additive layers include a positive electrode active material, a conductive agent, and a binder. The positive electrode is manufactured, for example, by coating a positive electrode additive slurry containing a positive electrode active material, a conductive agent, and a binder onto the positive electrode core, allowing the coating to dry, and then compressing it to form positive electrode additive layers on both sides of the positive electrode core.

[0023] The positive electrode active material is mainly composed of lithium-containing metal composite oxides. Examples of metal elements contained in these lithium-containing metal composite oxides include Ni, Co, Mn, Al, B, Mg, Ti, V, Cr, Fe, Cu, Zn, Ga, Sr, Zr, Nb, In, Sn, Ta, and W. A preferred example of a lithium-containing metal composite oxide is one containing at least one of Ni, Co, Mn, and Al.

[0024] Examples of conductive agents included in the positive electrode binder layer include acetylene black, carbon black such as Ketjen black, and carbon materials such as graphite. Examples of binders included in the positive electrode binder layer include fluoropolymers such as polytetrafluoroethylene (PTFE) and polyvinylidene fluoride (PVdF), polyacrylonitrile (PAN), polyimide resins, acrylic resins, and polyolefin resins. These resins can also be used in combination with cellulose derivatives such as carboxymethyl cellulose (CMC) or its salts, and polyethylene oxide (PEO).

[0025] The negative electrode 12 has a negative electrode core and negative electrode binder layers formed on both sides of the negative electrode core. For the negative electrode core, a metal foil stable within the potential range of the negative electrode 12, such as copper or a copper alloy, or a thin film with the metal disposed on the surface, can be used. The negative electrode binder layers contain a negative electrode active material and a binder. The negative electrode 12 is manufactured, for example, by coating a negative electrode binder slurry containing a negative electrode active material and a binder onto the negative electrode core, allowing the coating to dry, and then compressing it to form negative electrode binder layers on both sides of the negative electrode core.

[0026] For the negative electrode active material, carbon materials that reversibly absorb and release lithium ions are generally used. Preferred carbon materials include natural graphite such as flake graphite, block graphite, and amorphous graphite, as well as artificial graphite such as block graphite and graphitized mesophase carbon microspheres. The negative electrode additive layer may also contain silicon (Si) materials as the negative electrode active material. Alternatively, the negative electrode active material may also be a lithium-alloyed metal other than Si, an alloy containing that metal, or a compound containing that metal.

[0027] Similar to the case of the positive electrode 11, the binder contained in the negative electrode binder layer can be fluoropolymers, PAN, polyimide resins, acrylic resins, polyolefin resins, etc., but styrene-butadiene rubber (SBR) or its modifiers are preferred. In addition to SBR, the negative electrode binder layer may also contain CMC or its salts, polyacrylic acid (PAA) or its salts, polyvinyl alcohol, etc.

[0028] For the separator 13, a porous sheet material with ion permeability and insulation is used. Specific examples of porous sheets include microporous films, woven fabrics, and nonwoven fabrics. The preferred material for the separator 13 is polyolefin resin such as polyethylene or polypropylene, or cellulose. The separator 13 can be either a single-layer structure or a multilayer structure. A heat-resistant layer may also be formed on the surface of the separator 13.

[0029] An upper insulating plate 15 is disposed on the upper side of the electrode body 14, and a lower insulating plate 16 is disposed on the lower side of the electrode body 14. Figure 1 In the example shown, the positive lead 17 installed on the positive electrode 11 extends through the through hole of the upper insulating plate 15 toward the sealing body 19 and is connected to the lower surface of the sealing body 19 by welding or the like. On the other hand, the negative lead 18 installed on the negative electrode 12 extends through the outer side of the lower insulating plate 16 toward the bottom 20A of the outer packaging can 20 and is connected to the inner surface of the bottom 20A by welding or the like. The sealing body 19 with the positive lead 17 connected becomes the positive terminal, and the outer packaging can 20 with the negative lead 18 connected becomes the negative terminal.

[0030] A gasket 24 is provided between the outer can 20 and the sealing body 19 to ensure the airtightness of the battery interior and the insulation between the outer can 20 and the sealing body 19. The outer can 20 has a cylindrical portion 20B and a bottom 20A. The cylindrical portion 20B includes an annular slotted portion 28 and an annular shoulder 29. The slotted portion 28 is formed by spinning a portion of the cylindrical portion 20B to make it recessed radially inward. On the other hand, the shoulder 29 is formed by bending the upper end of the cylindrical portion 20B radially inward and riveting it to the flange portion (peripheral portion) 31 of the sealing body 19, extending radially inward. The sealing body 19 is held between the shoulder 29 and the slotted portion 28 through the gasket 24 by this riveting, thereby being fixed to the outer can 20.

[0031] The sealing body 19 is a circular plate-shaped component equipped with a current blocking mechanism. The sealing body 19 has a structure in which an inner terminal plate 21, an insulating plate 23, and a fracture plate 22 are stacked sequentially from the electrode body 14 side. The fracture plate 22 forms a valve body, sandwiching the insulating plate 23 and opposing the inner terminal plate 21. An opening 23A is formed in the radial center of the insulating plate 23, and a vent hole 23B is formed in the portion overlapping with the vent hole 21C of the inner terminal plate 21.

[0032] The fracture plate 22 has a valve portion 22A on its radially central side that breaks when the internal pressure of the battery exceeds a predetermined threshold. The valve portion 22A is connected to the central portion 21B of the internal terminal plate 21 via an opening 23A of the insulating plate 23 by welding or the like. The valve portion 22A includes a lower protrusion disposed in the radially central portion protruding inward toward the battery, and a thin-walled portion formed around the lower protrusion. The wall thickness of the thin-walled portion decreases as it moves radially outward.

[0033] The internal terminal plate 21 is a metal plate, comprising a thick-walled annular portion 21A for connecting the positive electrode lead 17, and a circular plate-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. A vent hole 21C is formed in the annular portion 21A. The positive electrode lead 17 is connected to the lower surface of the annular portion 21A. The internal terminal plate 21, to which the positive electrode lead 17 is connected, is electrically connected to the fracture plate 22, forming a current path from the electrode body 14 to the fracture plate 22.

[0034] When the internal pressure of the battery 10 increases, the valve portion 22A flips upwards axially, using the radially outer annular end 22B, which has lower rigidity in the thin-walled portion, as a fulcrum. Simultaneously with this flip, the central portion 21B separates from the annular portion 21A, or detaches from the valve portion 22A. Since the valve portion 22A is insulated relative to the annular portion 21A by the insulating plate 23, the current path is blocked due to the associated flip. When the internal pressure of the battery increases further, the annular end 22B of the thin-walled portion breaks, forming a gas outlet.

[0035] The structure of the sealing body 19 is not limited to Figure 1 The structure shown is as follows. For example, the sealing body 19 may also be composed of only fracture plates. Alternatively, the sealing body 19 may also have a laminated structure comprising two fracture plates, the laminated structure having an upwardly projecting protrusion at the radial center and having a terminal cap covering the fracture plates.

[0036] Figure 2 yes Figure 1 An enlarged sectional view of the upper side of the slotted portion 28. (See image below.) Figure 1 and Figure 2 As shown, the battery 10 has a pressing member 33 located between the axially oriented slotted portion 28 and the sealing body 19. The pressing member 33 presses the gasket 24 toward the sealing body 19, and more specifically, toward the flange portion 31 of the sealing body 19. In this embodiment, the flange portion 31 is formed by the peripheral portion of the fracture plate 22.

[0037] Figure 3 This is a perspective view of the outer can 20 and pressing component 33 cut along the axial direction from an oblique top view; it is an enlarged perspective view of the periphery of the slotted portion 28. (For example...) Figure 3As shown, the pressing member 33 has a ring-shaped structure and is fixed to the inner surface (upper surface) of the slotted portion 28 by an adhesive. Furthermore, the pressing member 33 only needs to be located between the slotted portion 28 and the pad 28, or it may not be fixed to the slotted portion 28. In this embodiment, the pressing member 33 is made of a resin material harder than the pad 24, but it may also be made of a metal material. Examples of resin materials include PP (polypropylene) and ABS resin.

[0038] The battery 10 disclosed herein can be manufactured, for example, by the following steps. Specifically, first, a cylindrical outer can 20 with a bottom is prepared, and the lower insulating plate 16, the electrode body 14, and the upper insulating plate 15 are housed within the outer can 20 in this order. Next, a welding rod (not shown) is inserted into the hollow portion of the electrode body 14, and the negative electrode lead 18 is resistance-welded to the bottom 20A of the outer can 20. Then, a portion of the cylindrical portion of the outer can 20 is spun to create a slotted portion 28.

[0039] Next, the pressing member 33 is fixed to the axially upper side and radially inward side of the slotted portion 28 using an adhesive. Then, after the gasket 24 is accommodated on the upper side of the slotted portion 28, a sealing body 19 with the positive electrode lead 17 welded to its lower surface is accommodated. Finally, after filling the outer can with a non-aqueous electrolyte, the front end of the opening side of the outer can 20 is riveted radially inward to seal the outer can 20, thereby manufacturing the battery 10.

[0040] Next, the effect obtained by providing a pressing member 33 between the axially slotted portion 28 and the sealing body 19 to press the gasket 24 toward the sealing body 19 will be explained. Figure 4 The reference example is battery 310. Figure 3 The corresponding enlarged cross-sectional view. The difference between battery 310 and battery 10 is that the pressing member 33 is absent.

[0041] Reference Figure 4 As the capacity of battery 310 increases, it is desirable to reduce the volume occupied by the components on the upper part of the electrode body, and it is desirable to reduce the thickness of the sealing body 319. However, if the thickness of the sealing body 319 is reduced, the rigidity of the sealing body 19 decreases. In this context, the following problem exists: when riveting the front end of the opening side of the outer packaging can 320, Figure 4 The riveting stress, indicated by arrow C, from the top to the bottom of the sealing body 319 is more likely to be located at a higher position than... Figure 4 The reaction force acting on the sealing body 319 from the slotted portion 328 upwards, as indicated by the middle arrow D, is located more radially inwards. The point of application (point of action) of the torque force acting on the sealing body 319 is more likely to be located radially inwards than the fulcrum.

[0042] Furthermore, as a result, the radial central portion of the sealing body 319, which has low rigidity, is easily deformed downwards due to the torque force. For example, when multiple batteries are electrically connected for modularization, the welding position of the sealing body 319 may deviate, resulting in problems such as the inability to perform modularization smoothly.

[0043] In contrast, according to the battery 10 of this disclosure, since a pressing member 33 is provided between the axially slotted portion 28 and the sealing body 19 to press the gasket 24 toward the sealing body 19, therefore, Figure 2 As indicated by arrows A and B, which show the direction of the force generated during riveting, the position of the fulcrum of the torque force can be controlled near the placement position of the pressing member 33, making the fulcrum close to the point of application (point of action). Therefore, the torque force acting on the central part of the sealing body 19 when riveting the front end of the opening side of the outer can 20 can be reduced. Therefore, even if the thickness of the sealing body 19 is reduced to increase the capacity, deformation of the sealing body 19 can be suppressed. Thus, the battery 10 according to this disclosure can achieve the following significant effect: it can simultaneously achieve a high capacity of the battery 10 and suppress deformation of the sealing body 19, which are in a trade-off relationship.

[0044] Furthermore, since the gasket 24 can be pressed towards the sealing body 19 by the pressing member 33, the compressive force of the gasket 24 around the pressing member 33 can be increased, thereby improving the sealing performance of the gasket 24. Additionally, as in this embodiment, if the flange portion 31 of the sealing body 19 is constructed using a fracture plate 22, the thickness of the sealing body 19 can be significantly reduced, making it particularly easy to increase capacity. Furthermore, if the pressing member 33 is constructed of resin material, the insulation of the sealing body 19 relative to the outer can 20 can be improved. Furthermore, if the annular pressing member 33 is positioned between the axially oriented slotted portion 28 and the sealing body 19, force can be applied uniformly to the sealing body 19 in the circumferential direction from the pressing member 33, thus effectively suppressing deformation of the sealing body 19. Moreover, the flange portion 31 of the sealing body 19 can also be constructed from a valve body comprising two or more components.

[0045] In order to reliably reduce the torque force acting on the central part of the sealing body 19 when riveting the front end of the opening side of the outer can 20, the axial height of the pressing member 33 is preferably 0.05 mm or more. In addition, since it is difficult to apply excessive force to the gasket 24 and the durability of the gasket 24 is easily improved, the axial height of the pressing member 33 is preferably 0.2 mm or less.

[0046] In order to reliably reduce the torque force acting on the central part of the sealing body 19 when riveting the front end of the opening side of the outer can 20, when the radial outer end 19a of the axial electrode body 14 side surface of the sealing body 19 (refer to...) Figure 2The axial distance between the 28th section and the slotted section is set as L1 (refer to...). Figure 2 In order to reliably reduce the torque force acting on the central part of the sealing body 19 when riveting the front end of the opening side of the outer can 20, the axial height of the pressing member 33 is preferably 0.05L1 or more. In addition, since it is difficult to generate excessive force on the gasket 24 and the durability of the gasket 24 is easily improved, the axial height of the pressing member 33 is preferably 0.5L1 or less.

[0047] Since it allows the fulcrum to be effectively close to the point of force (point of application), it is preferable that at least a portion of the pressing member 33 is located radially within the annular groove 35 defined by the slotted portion 28 (see reference). Figure 1 The radial inner end 35a in ) (refer to Figure 1 Between the outer portion located 0.5 mm radially outward from the inner end 35a. Furthermore, since the fulcrum can be effectively brought close to the point of force (point of action), it is preferable that the entire pressing member 33 is located radially inward from a position 0.5 mm radially outward from the inner end 35a, and more preferably in a position radially inward from a position 0.3 mm radially outward from the inner end 35a of the annular groove 35.

[0048] like Figure 1 and Figure 2 As shown, the slotted portion 28 has: an annular portion 28a axially opposite to the flange portion 31 and formed of a generally planar surface; and a curved portion 28c connected to the radially inner end 28b of the annular portion 28a and bent in a U-shape. Since the fulcrum can be effectively brought close to the point of force (point of action), it is preferable that at least a portion of the pressing member 33 is located radially outward than the inner end 28b of the annular portion 28a. Furthermore, since it is easy to install the pressing member 33, it is preferable that all of the pressing member 33 is located radially outward than the inner end 28b of the annular portion 28a.

[0049] Because it allows the fulcrum to be effectively close to the point of force (point of action), when the radial inner end 35a of the annular groove 35 is aligned with the maximum inner diameter position 37 of the outer can 20 (refer to...), Figure 1 The radial distance between them is set to L2 (refer to...). Figure 1 When pressing, preferably at least a portion of the pressing member 33 is located radially between the inner end 35a of the annular groove 35 and the outer portion located radially outward from the inner end 35a by 0.5L2, more preferably between the inner end 35a and the outer portion located radially outward from the inner end 35a by 0.35L2, and most preferably between the inner end 35a and the outer portion located radially outward from the inner end 35a by 0.30L2.

[0050] This disclosure is not limited to the above-described embodiments and their variations; various improvements and modifications can be made within the scope of the claims and their equivalents. For example, in the above-described embodiments, the annular pressing member 33 is described as being positioned between the axially oriented slotted portion 28 and the sealing body 19. However, as... Figure 5 That is, the battery 110 in the first modified example and Figure 3 As shown in the corresponding perspective view, the multiple pressing members 133 can also be arranged at approximately the same radial position with circumferential spacing. This reduces the amount of adhesive used to fix the multiple pressing members 133 to the inner surface of the slotted portion 28, thereby reducing the material cost of the battery 110.

[0051] In addition, such as Figure 6 That is, the battery 210 in the second modification example and Figure 3 As shown in the corresponding perspective view, the battery 210 may also include a plurality of first pressing members 233a arranged circumferentially at approximately the same first radial position, and a plurality of second pressing members 233b arranged circumferentially at approximately the same second radial position. Furthermore, at least a portion of the second pressing members 233b may be radially stacked between the circumference of two adjacent first pressing members 233a. This makes it difficult to apply excessive force to the sealing body 219 from below in a localized radial area, thus effectively suppressing deformation of the sealing body 219 according to specifications.

[0052] Alternatively, the cylindrical battery disclosed herein may also have the following structure.

[0053] Structure 1: A cylindrical battery comprising: an electrode body formed by winding a positive electrode and a negative electrode together with a separator; an outer can having a cylindrical portion including a slotted portion and accommodating the electrode body, the slotted portion being recessed radially inward throughout the entire circumference; a sealing body riveted to the opening of the outer can with a sealing member; and one or more pressing members located between the slotted portion and the sealing body in the axial direction, pressing the sealing member toward the sealing body.

[0054] Structure 2: The cylindrical battery according to Structure 1, wherein the flange of the sealing body is formed by a valve body.

[0055] Structure 3: The cylindrical battery according to Structure 1 or 2, wherein the pressing member is fixed to the inner surface of the slotted portion.

[0056] Structure 4: A cylindrical battery according to any one of structures 1 to 3, wherein the pressing member is made of a resin material that is harder than the sealing member.

[0057] Structure 5: A cylindrical battery according to any one of structures 1 to 4, wherein the axial height of the pressing member is 0.05 mm or more and 0.2 mm or less.

[0058] Structure 6: A cylindrical battery according to any one of Structures 1 to 4, wherein when the radial outer end of the axial side of the electrode body side of the sealing body is set to L1, the axial height of the pressing member is 0.05L or more and 0.5L or less.

[0059] Structure 7: A cylindrical battery according to any one of structures 1 to 6, wherein at least a portion of the pressing member is located radially between the inner radial end of the annular groove defined by the slotted portion and the outer portion located radially outward 0.5 mm from the inner end.

[0060] Structure 8: A cylindrical battery according to any one of structures 1 to 7, wherein the pressing member is an annular pressing member.

[0061] Structure 9: A cylindrical battery according to any one of structures 1 to 7, wherein a plurality of said pressing members are provided, the plurality of pressing members being arranged circumferentially spaced apart at substantially the same radial position.

[0062] Structure 10: A cylindrical battery according to any one of structures 1 to 7, wherein it comprises a plurality of pressing members, the plurality of pressing members including a plurality of first pressing members arranged circumferentially at approximately the same first radial position and a plurality of second pressing members arranged circumferentially at approximately the same second radial position, at least a portion of the second pressing members being radially stacked between two adjacent first pressing members circumferentially.

[0063] Explanation of reference numerals in the attached figures

[0064] 10, 110, 210: 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: Sealing body; 19a: Outer end of the lower surface of the sealing body; 20: Outer can; 20A: Bottom; 20B: Cylindrical part; 21: Internal terminal plate; 21A: Annular part; 21B: Central part; 21C: Vent hole; 22: 22A: Valve section; 23: Insulation plate; 23A: Opening; 23B: Vent hole; 24: Gasket; 28: Groove section; 28a: Circular section; 28b: Inner radial end of the circular section; 28c: Bend section; 29: Shoulder; 31: Flange section; 33, 133: Pressing member; 35: Annular groove; 35a: Inner end of the Annular groove; 37: Maximum inner diameter position of the outer can; 233a: First pressing member; 233b: Second pressing member.

Claims

1. A cylindrical battery, comprising: The electrode body is formed by winding the positive and negative electrodes together with a separator in between; The outer can has a cylindrical portion including a slotted section and accommodates the electrode body, the slotted section being recessed radially inward throughout the entire circumference; A sealing body, riveted and fixed to the opening of the outer can via a sealing member; and One or more pressing members are located between the slotted portion and the sealing body in the axial direction, and press the sealing members toward the sealing body side.

2. The cylindrical battery according to claim 1, wherein, The flange of the sealing body is formed by the valve body.

3. The cylindrical battery according to claim 1, wherein, The pressing member is fixed to the inner surface of the slotted portion.

4. The cylindrical battery according to claim 1, wherein, The pressing component is made of a resin material that is harder than the sealing component.

5. The cylindrical battery according to claim 1, wherein, The axial height of the pressing component is above 0.05 mm and below 0.2 mm.

6. The cylindrical battery according to claim 1, wherein, When the radial distance between the outer end of the axial side of the electrode body in the sealing body and the axial distance between the slotted portion is set to L1, The axial height of the pressing member is above 0.05L1 and below 0.5L1.

7. The cylindrical battery according to claim 1, wherein, At least a portion of the pressing member is located radially between the inner end of the annular groove defined by the slotted portion and the outer portion located radially outward 0.5 mm from the inner end.

8. The cylindrical battery according to any one of claims 1 to 7, wherein, The pressing member is a ring-shaped pressing member.

9. The cylindrical battery according to any one of claims 1 to 7, wherein, The cylindrical battery has multiple pressing components. The plurality of pressing members are arranged at approximately the same radial position with circumferential gaps.

10. The cylindrical battery according to any one of claims 1 to 7, wherein, The cylindrical battery has multiple pressing components. The plurality of pressing members include a plurality of first pressing members arranged circumferentially at approximately the same first radial position and a plurality of second pressing members arranged circumferentially at approximately the same second radial position. At least a portion of the second pressing member is stacked radially between two adjacent first pressing members in the circumferential direction.

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