Battery

Abstract

This battery (10) comprises an electrode body, an outer package (16), an opening sealing element (17), and an auxiliary electrode (40). The auxiliary electrode (40) has: a first joint part that is welded to an outer circumferential surface of a cylindrical part (30) of the outer package (16); a plate-like first upward extension part that extends from the first joint part toward the side of an open end (31) of the outer package; and a plate-like external connection part (47) that extends from the first upward extension part in a direction different from that of the first upward extension part so as to be connected to another conductor member. The cylindrical part (30) has a groove (33) in which an outer circumferential surface is indented in such a manner as to make an inner circumferential surface protrude. The opening sealing element (17) is disposed on the groove (33) with a gasket therebetween. The first joint part is joined with the groove and / or a portion of the outer circumferential surface of the cylindrical part located between the groove and the electrode body.

Description

[Technical field]

[0001] The present disclosure relates to batteries. [Background technology]

[0002] In recent years, batteries such as lithium-ion secondary batteries have come to be used as power sources for electric vehicles (EVs) and large-scale power storage facilities. When batteries are used as power sources for EVs, power storage facilities, and the like, a large number of batteries may be electrically connected to form a module for use. For example, a large number of batteries may be electrically connected in series and parallel to form a module. For this reason, it may be considered to collect current at one end of the multiple batteries.

[0003] Patent Document 1 describes a configuration in which, in one of the two batteries, a connection plate is connected by welding via a bracket to the outer circumferential surface of the cylindrical portion, which is one of the electrode terminals, and a terminal plate is connected to the sealing body, which is the other electrode terminal. In the other of the two batteries, a connection plate is connected to the outer circumferential surface of the cylindrical portion, and the connection plate is connected to the terminal plate of one of the batteries, thereby electrically connecting the two batteries. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 5256821 Summary of the Invention [Problem to be solved by the invention]

[0005] In order to collect current at one end of the battery, it is possible to weld a part of the auxiliary electrode to the outer circumferential surface of the cylindrical portion that serves as one electrode terminal, extend the auxiliary electrode upward from the open end of the cylindrical portion, and connect the part that extends in a direction different from the direction of extension to another conductive member. In this case, it is desirable to prevent the thermal effect of welding the auxiliary electrode to the cylindrical portion from being transmitted to the internal electrode body. In addition, when a groove is formed in the cylindrical portion such that the inner circumferential surface is recessed so that the inner circumferential surface protrudes inward, a gasket is placed on the groove, and the open end of the exterior body is closed by the gasket and the sealing body, it is also desirable to prevent the thermal effect of welding from being transmitted to the open end side of the gasket.

[0006] The object of the present disclosure is to prevent the thermal effects of welding from reaching the open end portion of the gasket and the electrode body in a battery configured such that an auxiliary electrode is welded to the outer peripheral surface of the tubular portion of the exterior body. [Means for solving the problem]

[0007] A battery according to one embodiment of the present disclosure comprises: an electrode body in which a first electrode and a second electrode are wound with a separator interposed therebetween; an exterior body having a cylindrical tube portion, an opening end formed at one end of the tube portion, and a bottom portion closing the other end of the tube portion, housing the electrode body and electrically connected to the first electrode; a sealing body that closes the open end of the exterior body together with a gasket and is electrically connected to the second electrode; and an auxiliary electrode having a first joint portion welded to the outer circumferential surface of the tube portion, a plate-shaped first upward extension portion extending from the first joint portion toward the open end, and a plate-shaped external connection portion extending in a different direction from the first upward extension portion and connecting to another conductive member, wherein the tube portion has a groove portion whose outer circumferential surface is recessed so that the inner circumferential surface of the tube portion protrudes, and the sealing body is disposed over the groove portion via a gasket, and the first joint portion is joined to at least one of the groove portion and the portion between the groove portion and the electrode body on the outer circumferential surface of the tube portion. In this disclosure, "top" refers to the open end side of the cylindrical portion of the battery, and "bottom" refers to the bottom side. Effect of the Invention

[0008] In the battery according to the present disclosure, the auxiliary electrode is welded to the outer peripheral surface of the tubular portion of the exterior body, which prevents the thermal effects of welding from reaching the open end portion of the gasket and the electrode body. [Brief description of the drawings]

[0009] [Figure 1] FIG. 2 is a perspective view showing an extracted upper part of a battery in one example (first example) of an embodiment. [Diagram 2] FIG. 2 is a front view of the battery of FIG. [Diagram 3] 3 is a cross-sectional view taken along line AA in FIG. 2, in which the thicknesses of the components of the battery are exaggerated. [Figure 4A] FIG. 2 is a perspective view of an auxiliary electrode of the battery of FIG. 1. [Figure 4B] 4B is a perspective view of the auxiliary electrode of FIG. 4A as viewed from the back side of FIG. 4A. [Diagram 5] 11 is a perspective view showing a state in which the exterior body of the battery is placed on a jig and an auxiliary electrode is joined to the outer peripheral surface of the exterior body by welding. FIG. [Figure 6] FIG. 11 is a perspective view of an upper portion of a battery in another example (second example) of the embodiment. [Figure 7A] FIG. 7 is a perspective view showing an auxiliary electrode taken out from FIG. 6. [Figure 7B] FIG. 7B is a top view of an arrangement in which a plurality of the batteries in FIG. 7A are arranged. [Figure 8] FIG. 13 is a perspective view of an upper portion of a battery in another example (third example) of the embodiment. [Figure 9] FIG. 9 is a perspective view showing an auxiliary electrode taken out from FIG. 8. [Figure 10] 10 is a perspective view of the auxiliary electrode in FIG. 9 as viewed from the back side of FIG. [Figure 11] FIG. 10 is a view taken along the arrow B in FIG. [Figure 12] 12 is a cross-sectional view taken along CC in FIG. 11 . [Figure 13] FIG. 10 is a development view of the auxiliary electrode in FIG. [Figure 14] FIG. 9 is a front view of the battery of FIG. 8. [Figure 15]15 is a cross-sectional view taken along the line DD in FIG. 14, in which the thicknesses of the components of the battery are exaggerated. [Figure 16] FIG. 13 is a perspective view of an upper portion of a battery in another example (fourth example) of the embodiment. [Figure 17] FIG. 17 is a perspective view showing an auxiliary electrode taken out from FIG. 16. [Figure 18] 18 is a perspective view of the auxiliary electrode in FIG. 17 as viewed from the back side of FIG. 17. [Figure 19] FIG. 18 is a development view of the auxiliary electrode in FIG. [Figure 20] FIG. 13 is a perspective view of an upper portion of a battery in another example (fifth example) of the embodiment. [Figure 21] FIG. 21 is a side view of the battery of FIG. 20. [Figure 22] FIG. 22 is a perspective view showing an auxiliary electrode taken out from FIG. 21. [Diagram 23] 23 is a perspective view of the auxiliary electrode in FIG. 22 as viewed from the back side of FIG. 22. [Figure 24] FIG. 13 is a perspective view of an auxiliary electrode taken out from a battery in another example (sixth example) of the embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] An example of an embodiment will be described in detail below. The drawings referred to in the description of the embodiment are schematic, so the specific dimensions of each component should be determined with reference to the following description. In this specification, the term "approximately..." is intended to include not only completely identical, but also substantially identical, when describing approximately identical as an example. The shapes, materials, numbers, and values ​​described below are examples for explanation and can be changed as appropriate depending on the use of the battery. In the following description, equivalent elements in all drawings will be given the same reference numerals.

[0011] [First Example of the Embodiment] Fig. 1 is a perspective view of an upper portion of a battery 10 in one example (first example) of an embodiment. Fig. 2 is a front view of the battery 10. Fig. 3 is a cross-sectional view taken along line AA in Fig. 2, in which the thicknesses of the components of the battery 10 are exaggerated.

[0012] As shown in Figs. 1 to 3, the battery 10 includes an exterior body 16, a sealing body 17, and an auxiliary electrode 40. The battery 10 is, for example, a non-aqueous electrolyte secondary battery. As shown in Fig. 3, an electrode body 14 and a non-aqueous electrolyte (not shown) are housed in the exterior body 16. The electrode body 14 has a positive electrode 11, a negative electrode 12, and a separator 13, and the positive electrode 11 and the negative electrode 12 are wound in a spiral shape with the separator 13 interposed therebetween. In the battery 10, the positive electrode 11 corresponds to the second electrode, and the negative electrode 12 corresponds to the first electrode. In Fig. 3, the positive electrode, the negative electrode, and the separator are each illustrated large to exaggerate the layout of the positive electrode 11, the negative electrode 12, and the separator 13 in the electrode body 14. Therefore, the battery of the present disclosure is not limited to the number of turns of the electrode body 14 in Fig. 3. The positive electrode 11, the negative electrode 12, and the separator 13 that constitute the electrode body 14 are all formed in a strip shape, and are wound up so as to be alternately stacked in the radial direction of the electrode body 14.

[0013] The nonaqueous electrolyte includes a nonaqueous solvent and an electrolyte salt dissolved in the nonaqueous solvent. The nonaqueous electrolyte is not limited to a liquid electrolyte, and may be a gel or solid electrolyte. In the following description, the open side of the exterior body 16 of the battery 10 is referred to as the "upper" side, and the bottom side is referred to as the "lower" side.

[0014] 3, the positive electrode lead 19 electrically connecting the positive electrode 11 and the sealing body 17 (positive electrode terminal) is provided, for example, approximately in the center between the inner winding end and the outer winding end of the electrode body 14, and extends from the upper end of the electrode body 14. The negative electrode leads 20a, 20b electrically connecting the negative electrode 12 and the outer casing 16 (negative electrode terminal) are provided, for example, at the inner winding end and the outer winding end of the electrode body 14, respectively, and extend from the lower end of the electrode body 14. Note that a plurality of positive electrode leads 19 may be provided, and only one or three or more negative electrode leads 20a, 20b may be provided.

[0015] The exterior body 16 is a metallic container having a cylindrical tube portion 30, an open end 31 formed at one end, i.e., the upper end, of the tube portion 30, and a bottom portion 32 (FIG. 3) closing the other end, i.e., the lower end, of the tube portion 30. The exterior body 16 accommodates the electrode body 14 and the non-aqueous electrolyte, and is electrically connected to the negative electrode 12. For this purpose, the negative electrode leads 20a, 20b of the negative electrode 12 extend to the bottom portion 32 side of the exterior body 16 and are connected to the inner surface of the bottom of the exterior body 16 by welding. In the battery 10, the exterior body 16 serves as a negative electrode terminal. The exterior body 16 is formed by drawing a metal such as steel, iron, aluminum, copper, or nickel.

[0016] The sealing body 17 closes the open end 31 of the exterior body 16 together with a gasket 27 described later, and is electrically connected to the positive electrode 11. The sealing body 17 and the exterior body 16 form a battery case. Insulating plates 18a and 18b are provided above and below the electrode body 14, respectively. The positive electrode lead 19 is connected to the positive electrode 11 and extends outward in the winding axis direction of the electrode body 14. The positive electrode lead 19 passes through a through hole in the insulating plate 18a and extends toward the sealing body 17, and is welded to the lower surface of the filter 22, which is the bottom plate of the sealing body 17. In the battery 10, the cap 26, which is the top plate of the sealing body 17 and is electrically connected to the filter 22, serves as the positive electrode terminal.

[0017] The gasket 27 is provided between the exterior body 16 and the sealing body 17, and ensures the sealing of the battery case 15 while electrically insulating the exterior body 16 and the sealing body 17. The cylindrical portion 30 of the exterior body 16 has a groove portion 33 in which the outer peripheral surface is recessed so that the inner peripheral surface of the cylindrical portion 30 protrudes inward. The groove portion 33 is formed, for example, by pressing the cylindrical portion 30 from the outside. The sealing body 17 is disposed so as to be supported on the groove portion 33 via the gasket 27. The groove portion 33 is formed in an annular shape along the circumferential direction of the cylindrical portion 30. The upper end portion 37 forming the open end 31 of the exterior body 16 is bent radially inward so as to press the gasket 27 from above.

[0018] The sealing body 17 is formed by stacking a filter 22, a lower valve body 23, an insulating member 24, an upper valve body 25, and a cap 26 in this order from the electrode body 14 side. Each member constituting the sealing body 17 has, for example, a disk shape or a ring shape, and each member except the insulating member 24 is electrically connected to each other. The lower valve body 23 and the upper valve body 25 are connected to each other at their respective centers, and the insulating member 24 is interposed between their respective peripheral edges. Since the lower valve body 23 has an air hole, if the internal pressure of the battery increases for some reason, the upper valve body 25 expands toward the cap 26 and moves away from the lower valve body 23, thereby cutting off the electrical connection between them. If the internal pressure increases further, the upper valve body 25 breaks, and gas is discharged from the opening of the cap 26.

[0019] The configurations of the positive electrode 11, the negative electrode 12, and the separator 13 will be described in detail. The positive electrode 11 includes a strip-shaped positive electrode core and a positive electrode mixture layer. The positive electrode mixture layer includes a positive electrode active material and a binder, and is formed on the positive electrode core. An example of a suitable positive electrode core is a metal foil mainly composed of aluminum or an aluminum alloy. The thickness of the positive electrode core is, for example, 5 μm to 30 μm. The positive electrode lead 19 is connected to the side of the upper end of the positive electrode 11, where the surface of the positive electrode core is exposed.

[0020] The positive electrode mixture layer is preferably formed on both sides in the thickness direction of the positive electrode core. The positive electrode mixture layer contains, for example, a positive electrode active material, a binder, and a conductive agent. The positive electrode 11 can be produced by applying a positive electrode mixture slurry containing a positive electrode active material, a binder, a conductive agent, and a solvent such as N-methyl-2-pyrrolidone (NMP) to both sides of the positive electrode core and compressing the coating.

[0021] The positive electrode 11 is capable of intercalating lithium ions. For this purpose, the positive electrode active material may be, for example, a lithium-containing transition metal oxide containing a transition metal element such as Co, Mn, or Ni. The lithium-containing transition metal oxide is, but is not limited to, a lithium-containing transition metal oxide represented by the general formula Li 1+xIt is preferably a composite oxide represented by MO₂ (where -0.2 < x ≤ 0.2 and M contains at least one of Ni, Co, Mn, and Al). Examples of the conductive material include carbon materials such as carbon black, acetylene black, ketjen black, and graphite. These may be used alone or in combination of two or more.

[0022] Examples of the binder include fluororesins such as polytetrafluoroethylene (PTFE) and polyvinylidene fluoride (PVdF), polyacrylonitrile (PAN), polyimide, acrylic resin, and polyolefin. Further, these resins may be used in combination with carboxymethyl cellulose (CMC) or its salt, polyethylene oxide (PEO), etc. These may be used alone or in combination of two or more.

[0023] The negative electrode 12 includes a strip-shaped negative electrode core and a negative electrode mixture layer. The negative electrode mixture layer contains a negative electrode active material and a binder and is formed on the negative electrode core. An example of a suitable negative electrode core is made of a metal foil mainly composed of copper or a copper alloy. The thickness of the negative electrode core is, for example, 5 μm to 30 μm.

[0024] Preferably, the negative electrode mixture layer is formed on both side surfaces in the thickness direction of the negative electrode core. The negative electrode 12 can be produced by applying a negative electrode mixture slurry containing a negative electrode active material, a binder, and water to both surfaces of the negative electrode core and compressing the coating film.

[0025] The negative electrode active material is not particularly limited as long as it can reversibly occlude and release lithium ions. For example, as the negative electrode active material, carbon materials such as natural graphite and artificial graphite, metals that alloy with lithium such as silicon (Si) and tin (Sn), or oxides containing metal elements such as Si and Sn are used.

[0026] Suitable examples of the negative electrode active material include graphite, SiO x (0.5 ≤ x ≤ 1.6) and silicon oxide represented by. The negative electrode mixture layer uses graphite or SiO as the negative electrode active material xIt may contain either one or both of the silicon oxides represented by , and when graphite and the silicon oxide are used in combination, the mass ratio of graphite to the silicon oxide is, for example, 99:1 to 80:20, preferably 97:3 to 90:10.

[0027] SiO x The silicon oxide represented by has, for example, a structure in which fine particles of Si are dispersed in an amorphous SiO2 matrix. SiO x The silicon oxide represented by may contain lithium silicate represented by Li 2y SiO (2+y) (0 < y < 2) and may have a structure in which fine particles of Si are dispersed in the lithium silicate phase.

[0028] SiO x It is preferable that a conductive film made of a material having higher conductivity than silicon oxide is formed on the particle surface of the silicon oxide represented by . The material constituting the conductive film is preferably at least one selected from carbon materials, metals, and metal compounds. Among them, it is particularly preferable to use a carbon material. The carbon film is formed, for example, at 0.5 to 10% by mass based on the mass of the SiO x particles.

[0029] As the binder contained in the negative electrode active material layer, a fluororesin, PAN, polyimide, acrylic resin, polyolefin, etc. can be used in the same manner as in the case of the positive electrode. When preparing the active material slurry using an aqueous solvent, it is preferable to use CMC or its salt, styrene-butadiene rubber (SBR), polyacrylic acid (PAA) or its salt, etc. These may be used alone or in combination of two or more.

[0030] The separator 13 is in the shape of a strip larger than the negative electrode 12 in the direction of the winding axis (the vertical direction in Figs. 2 and 3). 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. Suitable materials for the separator 13 include olefin-based resins such as polyethylene and polypropylene, and cellulose. The separator 13 may be a laminate having a cellulose fiber layer and a thermoplastic resin fiber layer such as an olefin-based resin.

[0031] Next, the auxiliary electrode 40 will be described. A battery module is formed by arranging a plurality of batteries 10 and electrically connecting the plurality of batteries 10 in series, in parallel, or in a combination of these. At this time, the plurality of batteries 10 are collected at the upper part. In addition, since the width in the radial direction of the upper end part 37 of the tubular part 30 of the exterior body 16 is small and a curved part having an arc-shaped cross section is formed, the upper end surface of the upper end part 37 is not flat or the flat part is often small. Therefore, when another conductive member is joined to the upper end of the tubular part 30 by welding, it is difficult to butt the two members together over a wide area before joining. For this reason, it is desired to improve the shape precision of the structure in which the other conductive member is connected to the battery.

[0032] In the embodiment, to eliminate such inconvenience, an auxiliary electrode 40 is joined to the outside of the vertical middle part of the tubular part 30, an upward extension part 45 of the auxiliary electrode 40 extends upward beyond the upper end part 37 of the tubular part 30, and an external connection part 47 is formed that extends from the upper end of the upward extension part 45 in a direction different from that of the upward extension part 45. Another conductive member 100 (FIG. 3) is joined by welding to the upper side of this external connection part 47. This allows most of the upper end surface of the external connection part 47 to be flat, making it easier to improve the shape precision of the structure in which the other conductive member 100 is connected to the battery 10.

[0033] Furthermore, in the embodiment, by restricting the position at which the auxiliary electrode 40 is welded to the tubular portion 30 as described below, it is possible to prevent the thermal effects of welding from affecting the opening end 31 side portion of the gasket 27 and the electrode body 14.

[0034] FIG. 4A is a perspective view showing the auxiliary electrode 40 taken out from FIG. 1. FIG. 4B is a perspective view showing the auxiliary electrode 40 from the back side of FIG. 4A. The auxiliary electrode 40 is formed by pressing a highly conductive metal plate such as copper, aluminum, iron, steel, or nickel to be bent into a substantially L-shaped cross section. The auxiliary electrode 40 has a joint 41 provided in the lower half and welded to the outer circumferential surface of the tube portion 30, a plate-shaped upward extension 45 provided in the upper half and extending from the upper end of the joint 41 to the upper side, which is the opening end 31 side of the tube portion 30, and a plate-shaped external connection portion 47 bent from the upper end of the upward extension 45 at a substantially right angle to the upward extension 45 and extending in a direction different from the upward extension 45. The joint 41 corresponds to the first joint, and the upward extension 45 corresponds to the first upward extension.

[0035] The joint 41 has a downward extension 49 that continues from the lower end of the upward extension 45, which is the end on the electrode body 14 side, and extends beyond the lower end of the groove 33. A first notch 50 is formed in a substantially U-shape with an open lower side, which is the electrode body 14 side, in a portion of the downward extension 49 facing the groove 33. In the downward extension 49, a first bent portion 51 is formed inside the first notch 50, which is bent from the downward extension 49 towards the tube portion 30. The tip of the first bent portion 51 may be cut off so as to be shorter than the vertical length of the first notch 50.

[0036] The joint 41 is joined to the tube part 30 of the exterior body 16 within the range indicated by the arrow α in FIG. 3. Specifically, the joint 41 is joined by welding to at least one of the groove 33 and the portion between the groove 33 and the electrode body 14 on the outer peripheral surface of the tube part 30 in the winding axis direction of the electrode body 14 (the vertical direction in FIG. 2 and FIG. 3). Preferably, the joint 41 is joined by welding to at least one of the portions of the outer surface of the groove 33 below the valley point G (FIG. 3) of the depression and the portion between the groove 33 and the electrode body 14 on the outer peripheral surface of the tube part 30 in the winding axis direction of the electrode body 14. The welding is laser welding, resistance welding, ultrasonic welding, or the like. Specifically, the first bent portion 51 of the joint 41 is joined to the outer surface of the groove 33 of the tube part 30 below the valley point G of the depression.

[0037] The external connection portion 47 extends so as to face the upper end portion 37 of the exterior body 16. Another conductive member 100 (FIG. 3) is joined to the upper end surface of the external connection portion 47 by welding, whereby the external connection portion 47 is electrically connected to the conductive member 100.

[0038] FIG. 5 is a perspective view showing a state in which the auxiliary electrode 40 is joined to the outer circumferential surface of the exterior body 16 by ultrasonic welding. When the auxiliary electrode 40 is joined to the exterior body 16, the exterior body 16 is held by a holding member 101 (anvil). The holding member 101 has a box portion 103 formed on the upper side of a main body portion 102 whose upper surface is a horizontal plane, inclined with respect to the upper surface of the main body portion 102 and having a holding hole 104 formed on the upper side. One radial half of the exterior body 16 is fitted into the holding hole 104, and the other radial half of the exterior body 16 protrudes upward from the opening of the box portion 103. In this state, the auxiliary electrode 40 is arranged at a predetermined position on the upper end of the exterior body 16, and in this state, the first bent portion 51 (FIG. 3) of the auxiliary electrode 40 is arranged along a lower open end portion in a circumferential part of the groove portion 33 of the exterior body 16. Then, ultrasonic welding horn 105 is pressed against first bent portion 51 of auxiliary electrode 40 from above, and welded to the lower open end of groove 33. Even if first bent portion 51 does not conform to the shape of the open end of groove 33 before welding, first bent portion 51 is welded by surface contact along the shape of groove 33. Note that the joint of auxiliary electrode 40 may be welded to only one of groove 33 of exterior body 16 and a portion of tube portion 30 that extends from the lower end of groove 33 to the bottom and does not face the electrode body on the inside.

[0039] In the above-described battery 10, the joint portion 41 of the auxiliary electrode 40 is joined to at least one of the groove portion 33 of the tubular portion 30 and a portion between the groove portion 33 and the electrode body 14 in the winding axis direction of the electrode body 14 on the outer circumferential surface of the tubular portion 30. This makes it possible to prevent the thermal influence of welding the auxiliary electrode 40 from reaching the portion of the gasket 27 on the opening end 31 side and the electrode body 14.

[0040] Furthermore, the joint portion 41 of the auxiliary electrode 40 is joined by welding to at least one of the outer surface of the groove 33 below the valley point G of the depression and a portion of the tube portion 30 extending from the lower end of the groove 33 to the bottom portion 32 and not facing the electrode body 14 on the inside. This makes it possible to prevent the thermal effect of welding the auxiliary electrode 40 from being exerted on the gasket 27 and electrode body 14 which support the sealing body 17 together with the groove 33.

[0041] In addition, the welding part of the auxiliary electrode 40 to the tubular part 30 is formed by a first bent part 51 that is bent to one side in the thickness direction of the downward extension part 49, which is the groove part 33 side of the exterior body 16, in a part surrounded by the first notch 50 of the downward extension part 49. This makes it easier for the first bent part 51 to approach or abut the tubular part 30 so as to follow the shape of the tubular part 30, for example, the curved surface of the cross section of the opening end of the groove part 33, or the outer surface of the groove part 33, so that the welding part and the tubular part 30 can be in surface contact with each other in a large area, and the joining strength can be easily increased. This makes it possible to improve the reliability of the electrical connection between the auxiliary electrode 40 and the tubular part 30. In the battery of the present disclosure, the first notch does not have to be U-shaped. For example, the downward extension part may be substantially L-shaped, consisting of a first straight line extending horizontally from an edge extending in the vertical direction of the battery and a second straight line extending downward from the tip of the first straight line. In the battery of the present disclosure, multiple first cutouts may be formed in one downward extension. Note that forming the first bent portion from a U-shaped first cutout provides vertically extending portions in the downward extension portion on both horizontal sides of the first bent portion compared to a first cutout extending from an edge of the downward extension portion, and this pair of portions can further reduce mechanical stress on the welded portion.

[0042] [Second embodiment] FIG. 6 is a perspective view of the upper part of the battery 10a in another example (second example) of the embodiment. FIG. 7A is a perspective view showing the auxiliary electrode 40a taken out from FIG. 6. In this example, the auxiliary electrode 40a is used, which has a configuration in which two auxiliary electrodes 40 shown in FIGS. 1 to 4B are arranged so as to be spaced apart in the circumferential direction of the battery 10a and their upper ends are connected. Specifically, the auxiliary electrode 40a has a first joint portion 55 and a first upward extension portion 57 arranged at one end portion in the circumferential direction of the exterior body 16 (left end portion in FIG. 7A), a second joint portion 62 and a second upward extension portion 64 arranged at the other end portion in the circumferential direction of the exterior body 16 (right end portion in FIG. 7A), and an external connection portion 69. The first joint portion 55 is provided at one end portion of the auxiliary electrode 40a in the lower half portion and welded to the outer circumferential surface of the tube portion 30. The first upward extension 57 is provided at one end of the auxiliary electrode 40a in the upper half, and is in the form of a plate extending upward from the upper end of the first joint 55 toward the open end 31 of the tube portion 30. The first joint 55 and the first upward extension 57 have the same shapes as the joint 41 and the upward extension 45 of the auxiliary electrode 40 shown in FIGS. 1 to 4B, respectively. Therefore, the first joint 55 has a first downward extension 58, a first notch 59 formed in the first downward extension 58, and a first bent portion 60 formed inside the first notch 59 in the first downward extension 58 and bent from the first downward extension 58 toward the tube portion 30, and the first bent portion 60 is joined to the groove portion 33.

[0043] The second joint 62 is welded away from the first joint 55 in the circumferential direction of the tubular portion 30 of the exterior body 16. The second joint 62 is provided in the lower half at the other end of the auxiliary electrode 40a and is welded to the outer circumferential surface of the tubular portion 30. The second upward extension 64 is provided in the upper half at the other end of the auxiliary electrode 40a and is a plate-like member extending upward from the upper end of the second joint 62 toward the open end 31 of the tubular portion 30. The second joint 62 and the second upward extension 64 have the same shapes as the first joint 55 and the first upward extension 57, respectively.

[0044] Specifically, the second joint portion 62 has a second downward extension portion 65 that continues from the lower end of the second upward extension portion 64, which is the end on the electrode body 14 (FIG. 3) side, and extends to a portion beyond the lower end of the groove portion 33. A second notch 66 is formed in a substantially U-shaped manner with an open lower side, which is the electrode body side, in a portion of the second downward extension portion 65 facing the groove portion 33. A second bent portion 67 is formed on the inside of the second notch 66 in the second downward extension portion 65, which is bent from the second downward extension portion 65 toward the tube portion 30. The tip of the second bent portion 67 may be cut so as to be shorter than the vertical length of the second notch 66.

[0045] The second joint 62, like the first joint 55, is joined by welding to at least one of the groove 33 and a portion between the groove 33 and the electrode body 14 on the outer peripheral surface of the tube 30 in the winding axis direction of the electrode body 14 (see FIG. 3). Preferably, the second joint 62 is joined by welding to at least one of the portions of the outer surface of the groove 33 below the valley point of the depression and the portions of the outer peripheral surface of the tube 30 between the groove 33 and the electrode body 14 in the winding axis direction of the electrode body 14. Specifically, the second bent portion 67 of the second joint 62 is joined to the outer surface of the groove 33 below the valley point of the depression. The first joint 55 and the second joint 62 may each be joined by welding to only one of the groove 33 and a portion between the groove 33 and the electrode body 14 on the outer peripheral surface of the tube 30.

[0046] The external connection portion 69 is an arc-shaped plate that is bent at a substantially right angle to the upper ends of the first upward extension portion 57 and the second upward extension portion 64 and connected to the upper ends of the first upward extension portion 57, 64, and extends in a direction different from the upward extension portions 57, 64, specifically, so as to face the upper end portion 37 of the exterior body 16. As a result, the first upward extension portion 57 and the second upward extension portion 64 are connected to two positions spaced apart in the circumferential direction of the external connection portion 69.

[0047] FIG. 7B is a top view of an arrangement in which a plurality of batteries 10a of FIG. 7A are arranged. A battery module is formed by electrically connecting the plurality of batteries 10a in series, parallel, or a combination of these in the state in which the plurality of batteries 10a are arranged as shown in FIG. 7B. At this time, the plurality of batteries 10a are arranged in three rows, namely, a first row A1, a second row A2, and a third row A3, in a predetermined first direction (the up-down direction in FIG. 7B), and the plurality of batteries 10a in each row are arranged in a second direction (the left-right direction in FIG. 7B) perpendicular to the first direction. The battery in the second row A2 is arranged in the center between the centers of two adjacent batteries in each of the first row A1 and the third row A3 in the second direction. As a result, the plurality of batteries 10a are arranged in a staggered manner, and the density of the plurality of batteries 10a in the space can be increased. Furthermore, as shown in FIG. 7B, when the plurality of batteries 10a are viewed from above, the shape of a line connecting the centers of the batteries 10a is a planar filling shape formed by arranging a plurality of rows of equilateral triangles arranged upside down. In this case, the circumferential centers of the first joint 55 and the second joint 62 of each auxiliary electrode 40a are arranged at a central angle of 60 degrees from the center of the battery. This makes it easy to arrange only one joint 55 (or 62) of one auxiliary electrode 40a in the central space (for example, the hatched area S in FIG. 7B) of three adjacent batteries arranged in a triangular arrangement as shown in FIG. 7B. Therefore, in the battery module, the portion that protrudes radially from the outer circumferential surface of the tube portion 30 of the exterior body 16 in each central space is reduced without increasing the interval between the plurality of batteries 10a, making it easy to ensure an insulation distance.

[0048] According to the configuration of this example, auxiliary electrode 40a has first joint 55 and second joint 62 welded at positions spaced apart in the circumferential direction of tubular portion 30 of exterior body 16, and first upward extension 57 extending upward from first joint 55 and second upward extension 64 extending upward from second joint 62 are connected to external connection portion 69. This provides two joint positions for auxiliary electrode 40a to exterior body 16, thereby increasing the joint strength between auxiliary electrode 40a and exterior body 16.

[0049] Furthermore, the welded portion of the auxiliary electrode 40a to the tubular portion 30 is formed by a first bent portion 60 and a second bent portion 67. As a result, each welded portion of the auxiliary electrode 40a to the tubular portion 30 is bent to fit the shape of the tubular portion 30, so that the area of ​​surface contact between the welded portion and the tubular portion 30 is increased, thereby increasing the joint strength. In this example, the other configurations and functions are similar to those of Figs. 1 to 5.

[0050] [Third embodiment] FIG. 8 is a perspective view showing an excerpt of an upper part of a battery 10b in another example (third example) of the embodiment. First, the problem to be solved by this example will be described. Specifically, in the background art, if the auxiliary electrode cannot be held in the outer casing before the auxiliary electrode is joined to the outer casing by welding, the workability of the welding operation is deteriorated. In addition, even after welding, if the auxiliary electrode is displaced relative to the outer casing by an external force, mechanical stress is applied to the joint between the auxiliary electrode and the outer casing, and there is a risk of the reliability of the joint being reduced. The purpose of this example is to improve the joint reliability between the outer casing and the auxiliary electrode in a battery. In this example, the auxiliary electrode 40b includes two support parts 74 extending in the circumferential direction of the battery 10b, and each support part 74 is inserted into the groove part 33 of the outer casing 16. This makes it easier to hold the auxiliary electrode 40b in the outer casing 16 before welding the auxiliary electrode 40b to the outer casing 16. In addition, even after welding, the joint reliability of the auxiliary electrode 40b to the outer casing 16 can be improved. Thus, by providing the supporting portion 74 into which the auxiliary electrode 40b is inserted into the groove portion 33, the workability of the welding operation can be improved and the reliability of the welded portion after welding the auxiliary electrode 40b to the outer casing 16 can be increased.

[0051] The auxiliary electrode 40b will be described in detail with reference to Figs. 9 to 13. Fig. 9 is a perspective view of the auxiliary electrode 40b in the battery 10b. Fig. 10 is a perspective view of the auxiliary electrode 40b in Fig. 9, seen from the back side. Fig. 11 is a view of the auxiliary electrode 40b in Fig. 9, seen from the arrow B. Fig. 12 is a cross-sectional view taken along line CC in Fig. 11. Fig. 13 is a development view of the auxiliary electrode 40b.

[0052] The auxiliary electrode 40b has a joint 70 provided at the lower end and welded to the outer circumferential surface of the cylindrical portion 30, a plate-shaped upward extension 72 connected to the upper side of the joint 70 and extending from the upper end of the joint 70 upward toward the open end side of the cylindrical portion 30, and a plate-shaped external connection portion 75 bent from the upper end of the upward extension portion 72 at a substantially right angle to the upward extension portion 72 and extending in a different direction from the upward extension portion 72. The joint 70 corresponds to the first joint, and the upward extension portion 72 corresponds to the first upward extension. The external connection portion 75 is the same as in the auxiliary electrode 40.

[0053] Two support parts 74 extending in the circumferential direction of the tube part 30 are connected to the lower ends of the upper extension part 72, which are the ends on the electrode body 14 (FIG. 3) side at both circumferential ends. The two support parts 74 are arc-shaped plates extending outward in opposite circumferential directions, and the two support parts 74 are arranged on the same plane. Note that in the battery of the present disclosure, the support parts do not need to be connected to the lower ends of the upper extension parts. For example, they may extend from both horizontal ends of the upper extension parts.

[0054] In addition, in the battery of the present disclosure, the support portion is not limited to an arc-shaped plate as long as it is inserted into the groove of the cylindrical portion. For example, the support portion may be a substantially rectangular plate.

[0055] The joint portion 70 continues from the lower end of the circumferential middle portion of the upward extension portion 72, and extends downward from the lower end of the groove portion 33. The portion of the joint portion 70 facing the groove portion 33 is curved into a mountain shape with an arc-shaped cross section so that it can be inserted into the opening of the groove portion 33.

[0056] The joint 70 is joined to the tubular portion 30 of the exterior body 16 in the portion indicated by a rectangle β in Fig. 8. Specifically, the joint 70 is joined by welding to a portion between the groove portion 33 on the outer circumferential surface of the tubular portion 30 and the electrode body 14 in the winding axis direction of the electrode body 14 (Fig. 3).

[0057] FIG. 14 is a front view of the battery 10b in FIG. 8. FIG. 15 is a view equivalent to the DD cross section of FIG. 14, in which the thicknesses of the components of the battery 10b are exaggerated. The joint 70 may be joined to the groove 33 by welding. The joint 70 may be joined to at least one of the outer surface of the groove 33 below the valley point G of the depression (FIG. 15) and a portion of the tube portion 30 extending from the lower end of the groove 33 to the bottom portion 32 and not facing the electrode body 14 on the inside. The welding may be laser welding, resistance welding, ultrasonic welding, or the like. For example, the joint 70 may be joined to the exterior body 16 by welding on the outer surface of the groove 33 below the valley point G of the depression together with the portion indicated by the rectangle β in FIG. 8 or instead of the portion indicated by the rectangle β.

[0058] The external connection portion 75 extends so as to face the upper end portion 37 of the exterior body 16. Another conductive member 100 (FIG. 15) is joined to the upper end surface of the external connection portion 75 by welding, whereby the external connection portion 75 is electrically connected to the conductive member 100.

[0059] In the auxiliary electrode 40b, a notch 73 (FIG. 11) parallel to the central axis O1 (FIG. 11) is formed between the base portion of the support portion 74 and the base portion of the joint portion 70. In this state, the two support portions 74 are disposed on both circumferential sides of the joint portion 70.

[0060] As shown in Fig. 13, a flat metal plate is punched into the shape of auxiliary electrode 40b before bending to obtain intermediate material 76, which is then bent along a number of folding lines (dotted lines a1 to a6 in Fig. 13) to form auxiliary electrode 40b. Dotted lines a1 to a4 and a6 indicate the positions that will become the peaks when the bending is performed so that the front side of the paper in Fig. 13 becomes the outer surface of the bent portion, and dotted line a5 indicates the position that will become the valley when the bending is performed so that the back side of the paper in Fig. 13 becomes the outer surface of the bent portion.

[0061] As shown in FIG. 8, the auxiliary electrode 40b is held by the exterior body 16 with the support portion 74 inserted into the groove portion 33, and in this state, the joint portion 70 of the auxiliary electrode 40b is joined to the exterior body 16 by welding. This makes it easier to hold the auxiliary electrode 40b on the exterior body 16 before welding the auxiliary electrode 40b to the exterior body 16, so that the auxiliary electrode 40b is prevented from shifting in position, improving the workability of the welding operation. Furthermore, even if a force is applied to the upward extension portion 72 of the auxiliary electrode 40b in the vertical direction or in a direction that causes rotation around an axis in a predetermined direction after welding, the support portion 74 engages with the lower end of the groove portion 33, thereby preventing the auxiliary electrode 40b from being displaced relative to the exterior body 16. This makes it possible to prevent the application of force in the above direction to the welded portion.

[0062] The battery of this embodiment includes an electrode body in which a first electrode and a second electrode are wound with a separator therebetween, an exterior body having a cylindrical tube portion, an opening end formed at one end of the tube portion, and a bottom portion closing the other end of the tube portion, and housing the electrode body and electrically connected to the first electrode, a sealing body closing the opening end of the exterior body together with a gasket and electrically connected to the second electrode, an auxiliary electrode having a first joint portion welded to the outer circumferential surface of the tube portion, a plate-shaped first upward extension portion extending from the first joint portion toward the opening end side, and a plate-shaped external connection portion extending from the first upward extension portion in a different direction and connecting to another conductive member, the tube portion having a groove portion whose outer circumferential surface is recessed so that the inner circumferential surface of the tube portion protrudes, and the auxiliary electrode having at least one support portion extending in the circumferential direction of the tube portion and inserted into the groove portion. With the above configuration, it is possible to suppress the displacement of the auxiliary electrode relative to the exterior body. This can increase the reliability of the joint between the auxiliary electrode and the exterior body.

[0063] More specifically, in the battery 10b described above, the auxiliary electrode 40b is welded to the outer circumferential surface of the tube portion 30 of the exterior body 16, and the auxiliary electrode 40b is held by the exterior body 16 with the support portion 74 inserted into the groove portion 33 before welding the auxiliary electrode 40b. This improves the workability of welding the auxiliary electrode 40b. Furthermore, even if a force is applied to the upward extension portion 72 of the auxiliary electrode 40b in the up-down direction or in the direction in which the auxiliary electrode 40b rotates after welding the auxiliary electrode 40b, the support portion 74 engages with the groove portion 33, thereby preventing the auxiliary electrode 40b from being displaced relative to the exterior body 16. This improves the joint reliability after welding the auxiliary electrode 40b to the exterior body 16.

[0064] Furthermore, the joint portion 70 of the auxiliary electrode 40b is joined to at least one of the groove portion 33 of the tubular portion 30 and a portion between the groove portion 33 and the electrode body 14 on the outer circumferential surface of the tubular portion 30. This makes it possible to prevent the thermal influence of welding the auxiliary electrode 40b from reaching the portion of the gasket 27 on the opening end 31 side and the electrode body 14.

[0065] Furthermore, joint portion 70 of auxiliary electrode 40b is joined by welding to at least one of the portion of the outer surface of groove 33 below valley point G of the depression and the portion between groove 33 and electrode body 14 on the outer circumferential surface of tube portion 30. This makes it possible to prevent the thermal effect of welding auxiliary electrode 40b from being exerted on gasket 27 and electrode body 14, which support sealing body 17 together with groove 33.

[0066] [Fourth embodiment] Fig. 16 is a perspective view showing an extracted upper portion of a battery 10c in another example (fourth example) of the embodiment. Fig. 17 is a perspective view of an auxiliary electrode 40c in the battery 10c. Fig. 18 is a perspective view of the auxiliary electrode 40c in Fig. 17, seen from the back side. Fig. 19 is a development view of the auxiliary electrode 40c.

[0067] In the configuration of this example, an auxiliary electrode 40c is used that has a configuration in which two parts of the auxiliary electrode 40b shown in Figs. 8 to 15 are arranged so as to be separated in the circumferential direction of the battery 10c and the upper ends of the two parts are connected. Specifically, the auxiliary electrode 40c has a first joint portion 77 and a first upward extension portion 79 arranged at one end portion in the circumferential direction of the exterior body 16 (the left end portion in Fig. 16), a second joint portion 80 and a second upward extension portion 82 arranged at the other end portion in the circumferential direction of the exterior body 16 (the right end portion in Fig. 16), and an external connection portion 84. The first joint portion 77 is one end portion of the auxiliary electrode 40c, and is provided at the lower end portion and welded to the outer circumferential surface of the tube portion 30. The first joint portion 77 extends from the lower end of the first upward extension portion 79 downward from the lower end of the groove portion 33. The first upward extension 79 is connected to the upper side of the first joint 77 at one end of the auxiliary electrode 40c, and is in the shape of a plate extending upward from the upper end of the first joint 77. One circumferential end of the lower end of the first upward extension 79 (the left end in Figs. 16 and 17, and the right end in Fig. 18) is connected to a first support 78 similar to the support 74 on one circumferential side of the auxiliary electrode 40b (the right side in Figs. 10 and 11, and the left side in Fig. 12).

[0068] The second joint 80 is welded away from the first joint 77 in the circumferential direction of the tubular portion 30 of the exterior body 16. The second joint 80 is provided at the lower end of the other end of the auxiliary electrode 40c and welded to the outer circumferential surface of the tubular portion 30. The second joint 80 extends downward from the lower end of the second upward extension 82 below the lower end of the groove portion 33. The second upward extension 82 is connected to the upper side of the second joint 80 at the other end of the auxiliary electrode 40c and is a plate-like member extending upward from the upper end of the second joint 80. A second support 81 similar to the support 74 on the other circumferential side of the auxiliary electrode 40b (the left side in FIGS. 10 and 11, the right side in FIG. 12) is connected to the other circumferential end of the lower end of the second upward extension 82 (the right end in FIGS. 16 and 17, the left end in FIG. 18).

[0069] The external connection portion 84 is an arc-shaped plate bent at a substantially right angle to the upper ends of the first upward extension portion 79 and the second upward extension portion 82 on the same side as the support portions 78, 81 and connected to the upper ends of the first upward extension portion 79 and the second upward extension portion 82, and extends in a different direction from the upward extension portions 79, 82. As a result, the first upward extension portion 79 and the second upward extension portion 82 are connected to two positions spaced apart in the circumferential direction of the external connection portion 84.

[0070] The first support portion 78 connected to the first upward extension portion 79 and the second support portion 81 connected to the second upward extension portion 82 are arc-shaped plates arranged close to each other. The two support portions 78, 81 are arranged on one plane.

[0071] 19, a flat metal plate is punched into the shape of auxiliary electrode 40c before bending to obtain intermediate material 85, which is then bent along a plurality of bending lines (dotted lines b1 to b10 in FIG. 19) to form auxiliary electrode 40c. Dotted lines b1 to b3, b5 to b8, and b10 are positions that will become peaks when the bent portion is bent so that the front side of the paper in FIG. 19 becomes the outer surface of the bent portion, and dotted lines b4 and b9 are positions that will become valleys when the bent portion is bent so that the back side of the paper in FIG. 19 becomes the outer surface of the bent portion.

[0072] 16 , the auxiliary electrode 40c is held by the exterior body 16 with the support portions 78, 81 inserted into the groove portions 33, and in this state, the joint portions 77, 80 of the auxiliary electrode 40c are joined by welding to the exterior body 16. In this state, the support portions 78, 81 are aligned along the shape of a portion of the groove portion 33 in the circumferential direction.

[0073] In this example, similar to the battery arrangement of the battery module shown in FIG. 7B, the auxiliary electrode 40c may be configured such that the circumferential centers of the first joint 77 and the second joint 80 are arranged at a central angle of 60 degrees from the center of the battery.

[0074] According to the configuration of this example, similarly to the auxiliary electrode 40a, the auxiliary electrode 40c has two bonding positions with the exterior body 16, which increases the bonding strength between the auxiliary electrode 40c and the exterior body 16. In this example, other configurations and functions are similar to those of the auxiliary electrodes 40, 40a, and 40b.

[0075] In addition, in the auxiliary electrodes 40, 40a, 40b, and 40c, the auxiliary electrodes 40b and 40c may be provided with only one support portion to be inserted into the groove portion 33.

[0076] [Fifth Example of the Embodiment] Fig. 20 is a perspective view of the upper part of a battery 10d in another example (fifth example) of the embodiment. Fig. 21 is a side view of the battery 10d. Fig. 22 is a perspective view of an auxiliary electrode 40d in the battery 10d. Fig. 23 is a perspective view of the auxiliary electrode 40d in Fig. 22 as seen from the back side.

[0077] In this example, unlike the auxiliary electrode 40b, the auxiliary electrode 40d does not have a joint portion that is connected to the lower end of the upward extension portion 72 and extends downward from the lower end of the groove portion 33. In this example, the auxiliary electrode 40d includes an arc-shaped support portion 86 that is connected to the lower end of the upward extension portion 72. The support portion 86 has an arc-shaped plate-shaped main body portion 87 and a curved surface portion 88 that has an arc-shaped cross section and is connected to the outer circumferential surface of the circumferential center portion of the main body portion 87. The support portion 86 is connected to the lower end of the upward extension portion 72 at the upper end of the curved surface portion 88. As a result, the support portion 86 is aligned along a direction that is approximately 90 degrees different from the upward extension portion 72. The support portion 86 extends in the circumferential direction of the tube portion 30 of the exterior body 16.

[0078] 21, the main body 87 of the support part 86 extends in the circumferential direction while meandering on both sides in the thickness direction over the entire circumferential direction. Therefore, the main body 87 has a wave washer shape. As a result, when the support part 86 is inserted into the groove part 33 of the exterior body 16, the upper and lower ends of the support part 86 approach the upper and lower ends of the groove part 33, respectively. At this time, the upper and lower ends of the support part 86 may be pressed against the upper and lower ends of the groove part 33.

[0079] The auxiliary electrode 40d is held by the outer casing 16 with the support portion 86 inserted into the groove portion 33 as shown in Figures 20 and 21. In this state, the curved portion 88 of the auxiliary electrode 40d and the opening lower end portion of the groove portion 33 are joined by welding at the position indicated by arrow P in Figure 21 as a joint.

[0080] According to the configuration of this example, the support portions 86 extend in the circumferential direction while meandering, and therefore, before welding of the auxiliary electrode 40d, separation of the auxiliary electrode 40d from the exterior body 16 can be suppressed by the support portions 86, and the auxiliary electrode 40d can be easily held on the exterior body 16 while suppressing displacement, such as tilting, of the support portions 86 within the groove portions 33. In this example, the other configurations and functions are similar to those of the auxiliary electrode 40b.

[0081] In addition, in the auxiliary electrodes 40b and 40c, the support portions 74, 78, and 81 may extend in the circumferential direction while meandering on both sides in the thickness direction, similar to the auxiliary electrode 40d.

[0082] [Sixth Example of the Embodiment] FIG. 24 is a perspective view of the auxiliary electrode 40e taken out of a battery in another example (sixth example) of the embodiment. In this example, the auxiliary electrode 40e is formed into a ring shape by joining two semicircular elements. Specifically, as shown in FIG. 24, the auxiliary electrode 40e includes a first semicircular element 90 and a second semicircular element 95. The first semicircular element 90 includes a semicircular plate-shaped first main body 91, an upward extension 72 connected to the outer periphery of one circumferential end (the left end in FIG. 24) of the first main body 91, and an external connection part 75 connected to the upper end of the upward extension 72. An engagement groove 92 is formed on the inner circumferential surface of each of both circumferential ends of the first main body 91, so that both circumferential ends of the first main body 91 are substantially L-shaped. The first main body 91 extends in the circumferential direction while meandering on both sides in the thickness direction, similar to the support part 86 of the auxiliary electrode 40d.

[0083] The second semicircular element 95 is semicircular plate-shaped, and has approximately L-shaped protrusions 96 formed on the inner circumferential sides of both circumferential ends, protruding in the circumferential direction. The second semicircular element 95 also extends in the circumferential direction while meandering on both sides in the thickness direction, similar to the first main body 91 of the first semicircular element 90. The auxiliary electrode 40e is ring-shaped as a whole, with the tips of the two protrusions 96 of the second semicircular element 95 being engaged with the two engagement grooves 92 of the first main body 91. The first main body 91 and the second semicircular element 95 correspond to a support portion.

[0084] With the first semicircular element 90 and the second semicircular element 95 separated, the auxiliary electrode 40e is inserted into the groove portion 33 from both sides in the diametrical direction of the battery so as to approach each other, and the two protrusions 96 of the second semicircular element 95 are engaged with the two engaging grooves 92 of the first semicircular element 90 to join the first semicircular element 90 and the second semicircular element 95. In this state, the auxiliary electrode 40e is held by the exterior body 16. In this state, the connecting portion between the first main body 91 and the upward extension portion 72 of the first semicircular element 90 of the auxiliary electrode 40e, or the end portion of the second semicircular element 95 on the upward extension portion 72 side, and the opening lower end portion of the groove portion 33 are joined by welding in the same manner as the auxiliary electrode 40d.

[0085] According to the configuration of this example, the ring-shaped portion of the auxiliary electrode 40e is disposed on the inner side of the entire circumference of the groove portion 33, so that before welding of the auxiliary electrode 40e, separation of the auxiliary electrode 40e in the radial direction from the outer casing 16 can be suppressed more than with the auxiliary electrode 40d. At the same time, the auxiliary electrode 40e can be more easily held in the outer casing 16. In this example, the other configurations and functions are similar to those of the auxiliary electrode 40d.

[0086] In the above examples, the external connection portions 47, 69, 75, 84 of the auxiliary electrodes 40, 40a to 40e extend to face the upper end portion 37 of the exterior body 16, but they may extend on the side opposite the upper end portion 37 of the exterior body 16. In addition, the external connection portions 47, 69, 75, 84 may be located below the upper end of the exterior body 16.

[0087] In addition, as in the configurations of Figures 1 to 5 or Figures 6 to 7, in a configuration in which the downward extension portion (downward extension portion 49, first downward extension portion 58) of the first joint (joint portion 41, first joint portion 55) has a first bent portion 51, 60 and the first bent portion is joined to the groove portion 33, or in a configuration in which the second downward extension portion 65 of the second joint portion 62 has a second bent portion 67 and the second bent portion is connected to the groove portion 33, the auxiliary electrode may be configured to have at least one support portion that extends circumferentially of the tubular portion 30 and is inserted into the groove portion 33.

[0088] In the configurations of the above examples, the case where the exterior body 16 is the negative electrode terminal and the sealing body 17 is the positive electrode terminal has been described, but the exterior body 16 may be the positive electrode terminal and the sealing body 17 may be the negative electrode terminal. In this case, the first electrode is the positive electrode and the second electrode is the negative electrode. [Explanation of symbols]

[0089] 10, 10a, 10b, 10c, 10d battery, 11 positive electrode, 12 negative electrode, 13 separator, 14 electrode body, 16 exterior body, 17 sealing body, 18a, 18b insulating plate, 19 positive electrode lead, 20a, 20b negative electrode lead, 22 filter, 23 lower valve body, 24 insulating member, 25 upper valve body, 26 cap, 27 gasket, 30 tube portion, 31 opening end, 32 bottom portion, 33 groove portion, 37 upper end portion, 40, 40a, 40b, 40c, 40d, 40e auxiliary electrode, 41 joint portion, 45 upward extension portion, 47 external connection portion, 49 downward extension portion, 50 first notch, 51 first bent portion, 55 first joint portion, 57 first upward extension portion, 58 First downward extension, 59 First notch, 60 First bent portion, 62 Second joint portion, 64 Second upward extension, 65 Second downward extension, 66 Second notch, 67 Second bent portion, 69 External connection portion, 70 Joint portion, 72 Upper extension, 73 Notch, 74 Support portion, 75 External connection portion, 76 Intermediate material, 77 First joint portion, 78 First support portion, 79 First upward extension, 80 Second joint portion, 81 Second support portion, 82 Second upward extension, 84 External connection portion, 85 Intermediate material, 86 Support portion, 87 Main body portion, 88 Curved portion, 90 First semicircular element, 91 First main body, 92 Locking groove, 95 Second semicircular element, 96 Protrusion, 100 Conductive member, 101 Holding member, 102 Main body, 103 box, 104 retaining hole, 105 horn.

Claims

1. an electrode assembly in which a first electrode and a second electrode are wound with a separator interposed therebetween; a cylindrical tube portion, an open end formed at one end of the tube portion, and a bottom portion closing the other end of the tube portion; an outer casing that houses the electrode assembly and is electrically connected to the first electrode; a sealing body that closes the open end of the exterior body together with a gasket and is electrically connected to the second electrode; an auxiliary electrode including a first joint portion welded to an outer circumferential surface of the cylindrical portion, a plate-shaped first upward extension portion extending from the first joint portion toward the opening end, and a plate-shaped external connection portion extending in a different direction from the first upward extension portion and connecting to another conductive member; the cylindrical portion has a groove portion in which the outer peripheral surface is recessed so that the inner peripheral surface of the cylindrical portion protrudes, the sealing body is disposed on the groove portion via the gasket, the first joint portion is joined to at least one of the groove portion and a portion between the groove portion and the electrode body on the outer circumferential surface of the cylindrical portion; And the first joint portion is The first upward extension portion is continuous with the electrode body side end and extends beyond the lower end of the groove portion. a downward extending portion, A first notch is formed in a portion of the downward extension portion facing the groove portion, the downward extension portion is adjacent to the first notch and has a first bent portion bent toward the exterior body, The first bent portion is joined to the groove portion, The first cutout has a U-shape that is open on the electrode body side, The first bent portion is disposed in a portion of the downward extension portion surrounded by the first cutout. battery.

2. An electrode body in which a first electrode and a second electrode are wound with a separator interposed therebetween; a cylindrical tube portion, an open end formed at one end of the tube portion, and a bottom portion closing the other end of the tube portion; an outer casing that houses the electrode assembly and is electrically connected to the first electrode; a sealing body that closes the open end of the exterior body together with a gasket and is electrically connected to the second electrode; an auxiliary electrode including a first joint portion welded to an outer circumferential surface of the cylindrical portion, a plate-shaped first upward extension portion extending from the first joint portion toward the opening end, and a plate-shaped external connection portion extending in a different direction from the first upward extension portion and connecting to another conductive member; the cylindrical portion has a groove portion in which the outer peripheral surface is recessed so that the inner peripheral surface of the cylindrical portion protrudes, the sealing body is disposed on the groove portion via the gasket, the first joint portion is joined to at least one of the groove portion and a portion between the groove portion and the electrode body on the outer circumferential surface of the cylindrical portion; The auxiliary electrode is a second joint portion welded away from the first joint portion in a circumferential direction of the tubular portion of the exterior body, and a second upward extension portion extending from the second joint portion toward the opening end, The first upward extension portion and the second upward extension portion are connected to two circumferentially separated positions of the external connection portion. battery.

3. An electrode body in which a first electrode and a second electrode are wound with a separator interposed therebetween; a cylindrical tube portion, an open end formed at one end of the tube portion, and a bottom portion closing the other end of the tube portion; an outer casing that houses the electrode assembly and is electrically connected to the first electrode; a sealing body that closes the open end of the exterior body together with a gasket and is electrically connected to the second electrode; an auxiliary electrode including a first joint portion welded to an outer circumferential surface of the cylindrical portion, a plate-shaped first upward extension portion extending from the first joint portion toward the opening end, and a plate-shaped external connection portion extending in a different direction from the first upward extension portion and connecting to another conductive member; the cylindrical portion has a groove portion in which the outer peripheral surface is recessed so that the inner peripheral surface of the cylindrical portion protrudes, the sealing body is disposed on the groove portion via the gasket, the first joint portion is joined to at least one of the groove portion and a portion between the groove portion and the electrode body on the outer circumferential surface of the cylindrical portion; And the first joint portion is The first upward extension portion is continuous with the electrode body side end and extends beyond the lower end of the groove portion. a downward extending portion, A first notch is formed in a portion of the downward extension portion facing the groove portion, the downward extension portion is adjacent to the first notch and has a first bent portion bent toward the exterior body, The first bent portion is joined to the groove portion, The auxiliary electrode is a second joint portion joined to the first joint portion in a circumferential direction of the tubular portion of the exterior body, and a second upward extension portion extending from the second joint portion toward the opening end, the first upward extension portion and the second upward extension portion are connected to two circumferentially separated positions of the external connection portion, The second joint portion is a second downward extension portion that is continuous with the electrode body side end of the second upward extension portion and extends beyond a lower end of the groove portion; A second notch is formed in a portion of the second downward extension portion facing the groove portion, the second downward extension portion is adjacent to the second cutout and has a second bent portion bent toward the exterior body, The second bent portion is joined to the groove portion. battery.

4. The battery according to claim 3, The second cutout has a U-shape that is open on the electrode body side, The second bent portion is disposed in a portion of the second downward extension portion surrounded by the second cutout. battery.

5. An electrode body in which a first electrode and a second electrode are wound with a separator interposed therebetween; a cylindrical tube portion, an open end formed at one end of the tube portion, and a bottom portion closing the other end of the tube portion; an outer casing that houses the electrode assembly and is electrically connected to the first electrode; a sealing body that closes the open end of the exterior body together with a gasket and is electrically connected to the second electrode; an auxiliary electrode including a first joint portion welded to an outer circumferential surface of the cylindrical portion, a plate-shaped first upward extension portion extending from the first joint portion toward the opening end, and a plate-shaped external connection portion extending in a different direction from the first upward extension portion and connecting to another conductive member; the cylindrical portion has a groove portion in which the outer peripheral surface is recessed so that the inner peripheral surface of the cylindrical portion protrudes, the sealing body is disposed on the groove portion via the gasket, the first joint portion is joined to at least one of the groove portion and a portion between the groove portion and the electrode body on the outer circumferential surface of the cylindrical portion; the auxiliary electrode has at least one support portion extending in a circumferential direction of the cylindrical portion and inserted into the groove portion; battery.

6. an electrode assembly in which a first electrode and a second electrode are wound with a separator interposed therebetween; a cylindrical tube portion, an open end formed at one end of the tube portion, and a bottom portion closing the other end of the tube portion; an outer casing that houses the electrode assembly and is electrically connected to the first electrode; The opening end of the exterior body is sealed with a gasket and electrically connected to the second electrode. A sealing body connected to the a first joint portion welded to an outer peripheral surface of the cylindrical portion; a plate-like first upward extension portion, and another conductive member extending in a different direction from the first upward extension portion. and an auxiliary electrode having a plate-shaped external connection portion for connection thereto; the cylindrical portion has a groove portion in which the outer peripheral surface is recessed so that the inner peripheral surface of the cylindrical portion protrudes, the auxiliary electrode has at least one support portion extending in a circumferential direction of the cylindrical portion and inserted into the groove portion, The first joint portion and the at least one support portion are arranged in a circumferential direction of the cylindrical portion. battery.

7. The battery according to claim 6, The at least one support portion has an arc shape that follows a shape of a circumferential portion of the groove portion. battery.

8. An electrode body in which a first electrode and a second electrode are wound with a separator interposed therebetween; a cylindrical tube portion, an open end formed at one end of the tube portion, and a bottom portion closing the other end of the tube portion; an outer casing that houses the electrode assembly and is electrically connected to the first electrode; The opening end of the exterior body is sealed with a gasket and electrically connected to the second electrode. A sealing body connected to the a first joint portion welded to an outer peripheral surface of the cylindrical portion; a plate-like first upward extension portion, and another conductive member extending in a different direction from the first upward extension portion. and an auxiliary electrode having a plate-shaped external connection portion for connection thereto; the cylindrical portion has a groove portion in which the outer peripheral surface is recessed so that the inner peripheral surface of the cylindrical portion protrudes, the auxiliary electrode has at least one support portion extending in a circumferential direction of the cylindrical portion and inserted into the groove portion, The at least one support portion includes two supports arranged on both sides of the first joint portion in the circumferential direction. Part battery.

9. An electrode body in which a first electrode and a second electrode are wound with a separator interposed therebetween; a cylindrical tube portion, an open end formed at one end of the tube portion, and a bottom portion closing the other end of the tube portion; an outer casing that houses the electrode assembly and is electrically connected to the first electrode; The opening end of the exterior body is sealed with a gasket and electrically connected to the second electrode. A sealing body connected to the a first joint portion welded to an outer peripheral surface of the cylindrical portion; a plate-like first upward extension portion, and another conductive member extending in a different direction from the first upward extension portion. and an auxiliary electrode having a plate-shaped external connection portion for connection thereto; the cylindrical portion has a groove portion in which the outer peripheral surface is recessed so that the inner peripheral surface of the cylindrical portion protrudes, the auxiliary electrode has at least one support portion extending in a circumferential direction of the cylindrical portion and inserted into the groove portion, The auxiliary electrode is a second joint portion welded to the cylindrical portion of the exterior body at a distance from the first joint portion in the circumferential direction of the cylindrical portion of the exterior body; a joint portion and a second upward extension portion extending from the second joint portion toward the opening end, The first upward extension and the second upward extension are provided at two positions spaced apart in the circumferential direction of the external connection portion. The lateral extension portion is connected to the The at least one support portion is connected to the first upward extension portion and is supported on the circumferential surface of the cylindrical portion. a first support portion extending in the forward direction and inserted into the groove portion; and a second support portion connected to the second upward extension portion. a second support portion extending in the circumferential direction and inserted into the groove portion; battery.

10. An electrode body in which a first electrode and a second electrode are wound with a separator interposed therebetween; a cylindrical tube portion, an open end formed at one end of the tube portion, and a bottom portion closing the other end of the tube portion; an outer casing that houses the electrode assembly and is electrically connected to the first electrode; The opening end of the exterior body is sealed with a gasket and electrically connected to the second electrode. A sealing body connected to the a first joint portion welded to an outer peripheral surface of the cylindrical portion; a plate-like first upward extension portion, and another conductive member extending in a different direction from the first upward extension portion. and an auxiliary electrode having a plate-shaped external connection portion for connection thereto; the cylindrical portion has a groove portion in which the outer peripheral surface is recessed so that the inner peripheral surface of the cylindrical portion protrudes, the auxiliary electrode has at least one support portion extending in a circumferential direction of the cylindrical portion and inserted into the groove portion, The at least one support portion extends in the circumferential direction in a serpentine manner. battery.

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