Capacitor

Abstract

To provide a capacitors having reduced dimensional variations.SOLUTION: A capacitor 10 comprises a capacitor device 1, a pair of external electrodes 2, and a metal member. The pair of external electrodes 2 are each provided at one of both ends of the capacitor device 1. The metal material covers at least one of the pair of external electrodes 2. The metal member has bottom plates 300 facing the external electrodes 2. The bottom plate 300 each have an electrode connecting cantilever 302 in contact with the external electrode 2.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates generally to capacitors, and more particularly to capacitors comprising a capacitor element. [Background technology]

[0002] Capacitors are passive components that store and release electric charges and are used as components in electronic devices. Capacitors can become defective when they absorb moisture, so capacitors with excellent moisture resistance are in demand.

[0003] For example, Patent Document 1 discloses a case-molded capacitor in which multiple capacitor elements are connected by a bus bar with a terminal portion for external connection at one end, which is housed in a case and resin-molded except for at least the terminal portion of the bus bar. It is shown that the resin used for the resin molding in this case-molded capacitor is mainly epoxy resin, and that moisture resistance is improved by adding 3 to 25 wt% of hollow spherical inorganic matter to this. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2006-294788 A Summary of the Invention [Problem to be solved by the invention]

[0005] Incidentally, since dimensional variations can occur between capacitors due to a pair of external electrodes provided at both ends of the capacitor element, there is also a demand for further reducing the dimensional tolerance between capacitors.

[0006] However, the capacitor described in Patent Document 1 is not sufficient for suppressing dimensional variations of the capacitor when high dimensional accuracy is required.

[0007] An object of the present disclosure is to provide a capacitor that is less susceptible to dimensional variations. [Means for solving the problem]

[0008] A capacitor according to an aspect of the present disclosure includes a capacitor element, a pair of external electrodes, and a metal member. The pair of external electrodes are provided at both ends of the capacitor element. The metal member covers at least one of the pair of external electrodes. The metal member has a bottom plate portion facing the external electrodes. The bottom plate portion is provided with a cantilevered electrode connection portion that contacts the external electrodes. Effect of the Invention

[0009] According to the present disclosure, a capacitor with reduced dimensional variation can be obtained. [Brief description of the drawings]

[0010] [Figure 1] FIG 1A is a schematic cross-sectional view of a capacitor according to an embodiment of the present disclosure. FIG 1B is an enlarged cross-sectional view showing an example of a metal cap in a capacitor according to an embodiment of the present disclosure. FIG 1C is a schematic side view of a capacitor according to an embodiment of the present disclosure. FIG 1D is a cross-sectional view showing a cross section cut along the PP cutting line in FIG 1A. [Diagram 2] 2A and 2B are perspective views of a capacitor with and without a heat shrink tube in accordance with an embodiment of the present disclosure. [Diagram 3] Figures 3A to 3D are schematic diagrams showing an example of a part of a process for producing a capacitor element according to an embodiment of the present disclosure, Figure 3E is a schematic side view of Figure 3B, Figure 3F is a schematic side view of Figure 3C, and Figure 3G is a schematic side cross-sectional view of Figure 3D. [Figure 4] FIG. 4 is a schematic cross-sectional view of a modified example of a capacitor according to an embodiment of the present disclosure. [Diagram 5]5A and 5B are perspective views of a modified capacitor according to an embodiment of the present disclosure, the modified capacitor including a heat shrink tube, and the modified capacitor according to an embodiment of the present disclosure, the capacitor not including a heat shrink tube. [Figure 6] Fig. 6A is a perspective view showing one step of a method for manufacturing a wound type capacitor element, and Fig. 6B is a perspective view of the wound type capacitor element. [Figure 7] Fig. 7A is a diagram (perspective view) showing one step of a method for manufacturing a multilayer capacitor element. Fig. 7B is a diagram (cross-sectional view) showing one step of a method for manufacturing a multilayer capacitor element. Fig. 7C is a partially cutaway perspective view of the multilayer capacitor element shown in Fig. 7B. Fig. 7D is a perspective view of the multilayer capacitor element. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] 1. Overview 1A, a capacitor 10 according to this embodiment includes a capacitor element 1, a pair of external electrodes 2, and a pair of metal caps 3. The pair of external electrodes 2 are provided on both ends of the capacitor element 1. The pair of metal caps 3 cover each of the pair of external electrodes 2.

[0012] Capacitor 10 does not have an outer case or a molded resin filled in the outer case as described in Patent Document 1. In other words, capacitor 10 employs a so-called caseless structure. Therefore, capacitor 10 can achieve a weight reduction at least equivalent to that of a conventional outer case.

[0013] As described above, the capacitor 10 includes the metal cap 3 that covers the external electrode 2. The metal cap 3 is less permeable to gases such as water vapor than the external electrode 2. Therefore, by covering the external electrode 2 with the metal cap 3 and preventing the external electrode 2 from directly contacting the outside air, it becomes easier to suppress moisture absorption by the external electrode 2. In this way, the capacitor 10 of this embodiment includes the metal cap 3, and therefore has excellent moisture resistance.

[0014] Furthermore, metal cap 3 in capacitor 10 of this embodiment has bottom plate portion 300 facing external electrode 2 and peripheral wall portion 301 covering part of the outer periphery of capacitor element 1.

[0015] However, for example, when the external electrode 2 is made of metallicon, the thickness of the external electrode 2 may not be uniform. In addition, both end faces of the capacitor element 1 (faces on which the external electrode 2 is formed) may not be flat because they include a plurality of cross sections of the first metallized film 71 and the second metallized film 72 (see FIGS. 6A and 6B) as described later. However, in this embodiment, an electrode connection part 302 is formed on the inner bottom part 300a on the inside of the bottom plate part 300 of the metal cap 3. The electrode connection part 302 is elastically deformable and is in contact with the external electrode 2. Therefore, when the metal cap 3 is attached to the external electrode 2 to fabricate the capacitor 10, the dimensions of the capacitor 10 can be adjusted while at least a part of the bottom plate part 300 of the metal cap 3 is in contact with the external electrode 2. That is, because the electrode connection portion 302 is elastically deformable, it is easy to adjust the distance (also referred to as the outermost spacing L) between an end of one metal cap 3 (e.g., first metal cap 31) and an end of the other metal cap 3 (e.g., second metal cap 32) in the capacitor 10. In other words, by having the electrode connection portion 302, the metal cap 3 can contribute to absorbing the dimensional tolerance of the capacitor 10. This makes it possible to reduce dimensional variation between the capacitors 10 produced.

[0016] Therefore, capacitor 10 of the present embodiment can be made lighter in weight, have high moisture resistance, and is less susceptible to dimensional variation in capacitor 10.

[0017] 2.Details The capacitor 10 according to this embodiment and the method for manufacturing the capacitor 10 will be described in detail below with reference to Figures 1A to 3G. Figure 2A is a perspective view of the capacitor 10 according to this embodiment. Figure 1A is a cross-sectional view of the capacitor 10 taken along the cutting line QQ in Figure 2A. Figure 2B is a perspective view of the capacitor 10 shown in Figure 2A with the heat shrink tube 6 removed.

[0018] The capacitor 10 according to the present embodiment employs a so-called caseless structure and does not include an exterior case as described in Patent Document 1. In other words, the capacitor 10 is a caseless capacitor. As shown in FIG. 1A, the capacitor 10 includes a capacitor element 1, a pair of external electrodes 2 (21, 22), and a pair of metal caps 3 (31, 32). Preferably, the capacitor 10 further includes a welding member 400. Preferably, the capacitor 10 further includes a capacitor element protective material 51. Preferably, the capacitor 10 further includes a filling member 50. Preferably, the capacitor 10 further includes a metal foil 4. Preferably, the capacitor 10 further includes a metal foil protective material 52. Preferably, the capacitor 10 includes a heat shrink tube 6. Each component will be described below. In this specification, the expression "A and / or B" means either "A", "B", or "A and B".

[0019] <Capacitor element> First, the capacitor element 1 (capacitor body) will be described. The capacitor element 1 has a plastic film as a dielectric. The capacitor element 1 includes a wound type capacitor element 7 (see FIG. 6B) and a multilayer capacitor element 8 (see FIG. 7D). The wound type capacitor element 7 and the multilayer capacitor element 8 will be described below.

[0020] <<Wound-type capacitor element>> Wound capacitor element 7 can be manufactured, for example, as follows. First, a metallized film is prepared. Specifically, the metallized film includes first metallized film 71 and second metallized film 72 (see FIG. 6A).

[0021] The metallized film includes a dielectric film and a conductive layer.

[0022] Specifically, first metallized film 71 has first dielectric film 701 and first conductive layer 711. First dielectric film 701 is a long film. First conductive layer 711 is formed on one side of first dielectric film 701, except for first margin portion 721. First margin portion 721 is a portion where first dielectric film 701 is exposed. First margin portion 721 is formed in a strip shape narrower than first conductive layer 711 along one long side of first dielectric film 701.

[0023] On the other hand, second metallized film 72 is formed in the same manner as first metallized film 71. That is, second metallized film 72 has second dielectric film 702 and second conductive layer 712. Second dielectric film 702 is a long film having the same width as first dielectric film 701. Second conductive layer 712 is formed on one side of second dielectric film 702, except for second margin portion 722. Second margin portion 722 is a portion where second dielectric film 702 is exposed. Second margin portion 722 is formed in a strip shape narrower than second conductive layer 712 along one long side of second dielectric film 702.

[0024] The first dielectric film 701 and the second dielectric film 702 are formed of, for example, polypropylene, polyethylene terephthalate, polyethylene naphthalate, polyphenyl sulfide, polystyrene, etc. The first conductive layer 711 and the second conductive layer 712 are formed by a method such as a vapor deposition method or a sputtering method. The first conductive layer 711 and the second conductive layer 712 are formed of, for example, aluminum, zinc, magnesium, etc.

[0025] Next, as shown in FIG. 6A, first metallized film 71 and second metallized film 72 are overlapped with their two long sides aligned. At this time, first dielectric film 701 or second dielectric film 702 is interposed between first conductive layer 711 and second conductive layer 712. Furthermore, the long side on which first margin portion 721 is formed and the long side on which second margin portion 722 is formed are reversed. In this way, first metallized film 71 and second metallized film 72 are wound up in an overlapped state, thereby obtaining cylindrical wound body 73. Next, the sides of this wound body 73 are pressed from both sides to process it into flat wound body 74 (see FIG. 6B). The cross section of flat wound body 74 is oval. By flattening in this way, space can be saved.

[0026] In this manner, the wound capacitor element 7 is obtained. Inside the wound capacitor element 7, the first conductive layer 711 serves as a first internal electrode, and the second conductive layer 712 serves as a second internal electrode. This pair of internal electrodes faces each other with a dielectric film (first dielectric film 701 or second dielectric film 702) interposed therebetween.

[0027] <<Stacked capacitor elements>> Meanwhile, multilayer capacitor element 8 can be manufactured, for example, as follows. First, a metallized film is prepared. Specifically, the metallized film includes first metallized film 81 and second metallized film 82 (see FIG. 7A).

[0028] The metallized film includes a dielectric film and a conductive layer.

[0029] Specifically, first metallized film 81 has first dielectric film 801 and first conductive layer 811. First dielectric film 801 is a rectangular film. First conductive layer 811 is formed on one side of first dielectric film 801, except for first margin portion 821. First margin portion 821 is a portion where first dielectric film 801 is exposed. First margin portion 821 is formed in a strip shape narrower than first conductive layer 811 along one side of first dielectric film 801.

[0030] On the other hand, second metallized film 82 is formed in the same manner as first metallized film 81. That is, second metallized film 82 has second dielectric film 802 and second conductive layer 812. Second dielectric film 802 is a rectangular film having the same size as first dielectric film 801. Second conductive layer 812 is formed on one side of second dielectric film 802, except for second margin portion 822. Second margin portion 822 is a portion where second dielectric film 802 is exposed. Second margin portion 822 is formed in a strip shape narrower than second conductive layer 812 along one side of second dielectric film 802.

[0031] The first dielectric film 801 and the second dielectric film 802 are formed of, for example, polypropylene, polyethylene terephthalate, polyethylene naphthalate, polyphenyl sulfide, polystyrene, etc. The first conductive layer 811 and the second conductive layer 812 are formed by a method such as a vapor deposition method or a sputtering method. The first conductive layer 811 and the second conductive layer 812 are formed of, for example, aluminum, zinc, magnesium, etc.

[0032] Next, as shown in FIG. 7A and FIG. 7B, first metallized film 81 and second metallized film 82 are alternately stacked with their four sides aligned. At this time, first dielectric film 801 or second dielectric film 802 is interposed between first conductive layer 811 and second conductive layer 812. Furthermore, one side on which first margin portion 821 is formed and one side on which second margin portion 822 is formed are reversed. In FIG. 7A, first margin portion 821 is disposed at the rear (negative direction of X-axis) and second margin portion 822 is disposed at the front (positive direction of X-axis). In this way, a plurality of first metallized films 81 and second metallized films 82 are stacked and integrated to obtain laminate 83 as shown in FIG. 7B and FIG. 7C. Furthermore, laminate 83 is covered with protective film 84 except for the front surface (surface facing the positive direction of X-axis) and the rear surface (surface facing the negative direction of X-axis). The protective film 84 is an electrically insulating film.

[0033] In this manner, the multilayer capacitor element 8 is obtained. Inside the multilayer capacitor element 8, the first conductive layer 811 serves as a first internal electrode, and the second conductive layer 812 serves as a second internal electrode. This pair of internal electrodes faces each other with a dielectric film (the first dielectric film 801 or the second dielectric film 802) interposed therebetween.

[0034] <External electrode> Next, the external electrodes 2 will be described. As shown in FIG. 1A, the pair of external electrodes 2 is a first external electrode 21 and a second external electrode 22. The pair of external electrodes 2 is provided on both ends of the capacitor element 1. The pair of external electrodes 2 is electrically connected to each of the pair of internal electrodes of the capacitor element 1. The external electrodes 2 can be formed, for example, by metallicon (metal spraying method). The material of the external electrodes 2 is not particularly limited, but includes, for example, zinc. The external electrodes 2 may be formed only of zinc, or may be formed of a mixture of zinc and other metals such as tin. Furthermore, it is preferable to use a material with a low melting point as the material of the external electrodes 2. In this case, when forming the external electrodes 2 by metallicon, defects are unlikely to occur in the capacitor element 1 due to heat. The material of the external electrodes 2 preferably has a melting point of, for example, 700° C. or less, and more preferably has a melting point of 450° C. or less.

[0035] In the case of the wound capacitor element 7, as shown in Fig. 6B, the external electrodes 2 (first external electrode 21 and second external electrode 22) are formed on both end surfaces of the flat wound body 74 using metallicon. The first external electrode 21 is electrically connected to the first conductive layer 711 (first internal electrode). The second external electrode 22 is electrically connected to the second conductive layer 712 (second internal electrode). The first conductive layer 711 and the second conductive layer 712 form a pair of internal electrodes.

[0036] On the other hand, in the case of the multilayer capacitor element 8, as shown in Fig. 7D, external electrodes 2 (first external electrode 21 and second external electrode 22) are formed on the front and rear surfaces of the laminate 83 using metallicon. The first external electrode 21 is electrically connected to a first conductive layer 811 (first internal electrode). The second external electrode 22 is electrically connected to a second conductive layer 812 (second internal electrode). The first conductive layer 811 and the second conductive layer 812 form a pair of internal electrodes.

[0037] As shown in FIG. 1A and FIGS. 2A to 2B, a capacitor 10 according to this embodiment employs a wound capacitor element 7 as a capacitor element 1.

[0038] <Metal cap> Next, the metal cap 3 will be described. The metal cap 3 is a cylindrical cap made of metal with a bottom. The metal cap 3 covers both ends of the capacitor element 1 and the external electrode 2, so that the external electrode 2 is covered with the metal cap 3. In this disclosure, "covering" includes direct covering and indirect covering. For example, "A covers B" includes "A and B are in contact with each other and A directly covers B" and "A and B are not in contact with each other and A indirectly covers B."

[0039] The shape of the opening of the metal cap 3 is preferably substantially the same as the shape of both ends of the capacitor element 1, or has a circumferential dimension slightly larger than the shape of both ends of the capacitor element 1. In this embodiment, since the capacitor element 1 is a wound type capacitor element 7, the shape of the opening of the metal cap 3 is an oval shape. If the capacitor element 1 is a stacked type capacitor element 8, the shape of the opening of the metal cap 3 is a rectangle.

[0040] The pair of metal caps 3 are a first metal cap 31 and a second metal cap 32. The pair of metal caps 3 are placed on both ends of the capacitor element 1. In this manner, the pair of metal caps 3 cover each of the pair of external electrodes 2. In this embodiment, the first metal cap 31 covers the first external electrode 21, and the second metal cap 32 covers the second external electrode 22.

[0041] The metal cap 3 has a bottom plate portion 300 and a peripheral wall portion 301 covering at least a part of the outer circumferential surface 1a of the capacitor element. The bottom plate portion 300 includes an inner bottom portion 300a which is the inner bottom portion of the metal cap 3 and has a surface facing the external electrode 2, and an outer bottom portion 300b which is the outer bottom portion of the metal cap 3 and has a surface opposite to the inner bottom portion 300a. The peripheral wall portion 301 protrudes from the periphery of the bottom plate portion 300.

[0042] The metal cap 3 has an opening edge 3c on the opening side of the peripheral wall portion 301 (i.e., the side opposite to the bottom plate portion 300), which forms the outer periphery of the opening of the metal cap 3 (see FIG. 1B). The opening edge 3c of the metal cap 3 is located on the outer periphery surface 1a of the capacitor element 1 or near the outer periphery surface 1a. In FIG. 1A, the opening edge 31c of the first metal cap 31 and the opening edge 32c of the second metal cap 32 are located near the outer periphery surface 1a of the capacitor element 1. In the capacitor 10, the opening edge 3c (31c, 32c) of the metal cap 3 may or may not be in contact with the capacitor element 1.

[0043] At least a part of the inner bottom 300a of the metal cap 3 and the external electrode 2 are electrically connected. The metal cap 3 in the capacitor 10 of this embodiment has an electrode connection part 302. The electrode connection part 302 is elastically deformable and is in contact with the external electrode 2. The electrode connection part 302 is provided on the inner bottom 300a of the bottom plate part 300. Therefore, in the capacitor 10 of this embodiment, the metal cap 3 and the external electrode 2 are electrically connected via the electrode connection part 302. Since the electrode connection part 302 is elastically deformable, it is easy to adjust the distance (also called the distance L between the outermost parts) between the end of one metal cap 3 (e.g., the first metal cap 31) and the end of the other metal cap 3 (e.g., the second metal cap 32) in the capacitor 10. In other words, since the metal cap 3 has the electrode connection part 302, it can contribute to absorbing the dimensional tolerance of the capacitor 10. This makes it possible to reduce the dimensional variation between the capacitors 10 to be manufactured.

[0044] In FIG. 1A, the electrode connection part 312 in the bottom plate part 310 (inner bottom part 310a) of the first metal cap 31 is electrically connected to the first external electrode 21, and the electrode connection part 322 in the bottom plate part 320 (inner bottom part 320a) of the second metal cap 32 is electrically connected to the second external electrode 22. In the capacitor 10, the electrode connection part 302 is fixed in an elastically deformed state. More specifically, the electrode connection part 302 in the capacitor 10 is formed of an elastically deformable member, and is fixed in a state elastically deformed (e.g., contracted) from the original state by, for example, pressing. The degree of elastic deformation of the electrode connection part 302 is appropriately set according to the dimensions of the capacitor 10. However, since it is sufficient that the electrode connection part 302 of the metal cap 3 is elastically deformable and configured to contact the external electrode 2, it is not necessarily required that the electrode connection part 302 is fixed in the capacitor 10 by elastic deformation. For example, when a pair of metal caps are attached to the capacitor element 1, if the distance L between the outermost sides of the pair of metal caps 3 when attached is approximately equal to the dimension Lc of a specified capacitor 10, the caps will be fixed in place without elastic deformation.

[0045] A more preferred embodiment of the electrode connection portion 302 in the metal cap 3 will be described. Fig. 1B shows an enlarged cross-sectional view of the metal cap 3 of this embodiment. Fig. 1C is a view (side view) of the capacitor 10 seen from the side surface on the bottom plate portion 310 side of the first metal cap 31. Fig. 1D is a side cross-sectional view cut along the PP cutting line in Fig. 1A. Note that the heat shrink tube 6 is omitted in Figs. 1C and 1D.

[0046] The electrode connection portion 302 is preferably a notch portion 303. The notch portion 303 is formed by cutting out a part of the outer bottom portion 300b on the outer side of the bottom plate portion 300 of the metal cap 3 toward the inner bottom portion 300a side. The notch portion 303 is elastically deformable. In this case, when the metal caps 3 are attached to the capacitor element 1 to fabricate the capacitor 10, the notch portions 303 of the pair of metal caps 3 are elastically deformable, which makes it easy to align the metal caps 3 when they are attached.

[0047] As described above, the cutout portion 303 is formed by cutting out a part of the outer bottom portion 300b on the outer side of the bottom plate portion 300 toward the inner bottom portion 300a. In other words, the cutout portion 303 is preferably formed integrally with the bottom plate portion 300 of the metal cap 3.

[0048] The notch portion 303 has an inclined piece 303a and a bent piece 303b. The notch portion 303 is formed by cutting out the bottom plate portion 300 to form the inclined piece 303a, and further, the end portion of the inclined piece 303a is bent. In FIG. 1A, the bent piece 303b is formed to be approximately parallel to the external electrode 2. In addition, the bent piece 303b in the electrode connection portion 302 (notch portion 303) is in contact with the external electrode 2. This can improve the electrical connection between the external electrode 2 and the metal cap 3. In this embodiment, when the metal cap 3 is attached to the capacitor element 1, the position of the metal cap 3 can be adjusted while the bent piece 303b of the notch portion 303 is in contact with the external electrode 2. At this time, when the bent piece 303b in the notch portion 303 is pressed in, the notch portion 303 is elastically deformed, and the position of the metal cap 3 is adjusted. This allows the metal cap 3 to be attached so as to fit the predetermined dimension Lc of the capacitor 10. Furthermore, in this case, it becomes easier to weld the metal cap 3 to the external electrode 2 in the capacitor 10. However, the cutout portion 303 does not have to have, for example, the bent piece 303b. In this case, it is sufficient that, for example, the inclined piece 303a is configured to come into contact with the external electrode 2. Note that the inclined piece 303a and / or the bent piece 303b in this embodiment are elastically deformed in advance in the capacitor 10.

[0049] The dimensions of the cutout 303 are not particularly limited and can be appropriately adjusted so that at least a portion of the metal cap 3 contacts the opposing external electrode 2. The width interval of the cutout 303 in the direction perpendicular to the opposing external electrode 2 of the bent piece 303b, for example, the length from the inner bottom 300a to the tip of the bent piece 303b, may be 3 mm or less.

[0050] In the above, the cutout portion 303 is formed by cutting the bottom plate portion 300 from the outer bottom portion 300b side to the inner bottom portion 300a side, but this is not limited to the above. In addition, in Fig. 1A, one cutout portion 303 is formed in the metal cap 3, but the number of cutout portions 303 may be multiple, and for example, the metal cap 3 may have multiple cutout portions 303.

[0051] The electrode connection portion 302 may be formed at any position on the inner bottom portion 300a of the bottom plate portion 300, but for example, the notch portion 303 is preferably located approximately in the center of the bottom plate portion 300 (inner bottom portion 300a). For example, the center position of the notch portion 313 in the first metal cap 31 preferably overlaps with the center position of the first external electrode 21. Similarly, the center position of the notch portion 323 in the second metal cap 32 preferably overlaps with the center position of the second external electrode 22.

[0052] The metal cap 3 preferably has an opening 305. The opening 305 is a hole formed penetrating from the outer bottom 300b to the inner bottom 300a. In this case, the electrode connection portion 302 in the metal cap 3 and the external electrode 2 can be easily fixed through the opening 305 in the metal cap 3. Specifically, the electrode connection portion 302 and the external electrode 2 can be welded, for example, by brazing, through the opening 305 from the outside of the metal cap 3 (i.e., the outer bottom 300b side) through the opening 305 to produce a welded member 400 (described later). In this case, the metal cap 3 is fixed to the capacitor 10 by the welded member 400. Furthermore, when the metal cap 3 has the opening 305, the metal cap 3 and the external electrode 2 can be easily joined even if the outer bottom 300b of the metal cap 3 is flat. For example, the metal cap 3 and the external electrode 2 can be easily joined without having to recess the bottom plate portion 300 of the metal cap 3 from the outer bottom 300b to the inner bottom 300a side. Therefore, if the metal cap 3 has the opening 305, the flatness of the outer side of the bottom plate portion 300 can be maintained.

[0053] When the metal cap 3 has the cutout portion 303 as the electrode connection portion 302, the opening 305 may be a hole formed by forming the cutout portion 303 in the bottom plate portion 300. Specifically, for example, the opening 305 includes a cutout groove 306, and the cutout groove 306 is a groove formed when the cutout portion 303 is formed by cutting out a part of the bottom plate portion 300 (see FIG. 3E).

[0054] As long as the metal cap 3 is elastically deformable at the inner bottom portion 300a and has the electrode connection portion 302 that contacts the external electrode 2 as described above, the outer shape of the metal cap 3 is not particularly limited.

[0055] The distance L between the outermost portions of the pair of metal caps 3 in this embodiment is the distance between the outermost portions of the pair of metal caps 3, and is a length that defines the dimension Lc of the capacitor 10. For example, the distance L between the outermost portions of the pair of metal caps 3 is the distance (spacing) from the outside of the bottom plate portion 310 (outer bottom portion 310b) of the first metal cap 31 to the outside of the bottom plate portion 320 (outer bottom portion 320b) of the second metal cap 32.

[0056] Thus, according to the present embodiment, the metal cap 3 has the elastically deformable electrode connection portion 302, which makes it easy to adjust the distance L between the outermost portions of the pair of metal caps 3 in the capacitor 10. This can make it possible to reduce dimensional variations between the capacitors 10.

[0057] In the pair of metal caps 3 of the capacitor 10, the first metal cap 31 and the second metal cap 32 may have the same shape or different shapes. For example, one of the pair of metal caps 3 may not have the elastically deformable electrode connection portion 302. In this case, even if the second metal cap 32 does not have the electrode connection portion 322, as long as the first metal cap 31 has the electrode connection portion 312, the electrode connection portion 312 can be elastically deformed and brought into contact with the first external electrode 21, and the positioning can be performed when the capacitor 10 is fabricated. In this case, the electrical connection between the second metal cap 32 and the second external electrode 22 can be ensured by bringing the inner bottom portion 320a of the second metal cap 32 into contact with the second external electrode 22.

[0058] It is preferable that the outer circumferential dimension of the opening edge 3c of the metal cap 3 is slightly larger than the outer circumferential dimension of the capacitor element 1. That is, the width dimension of the metal cap 3 in a side cross-sectional view is larger than the width dimension of the capacitor element 1 in a side view (see FIG. 1A). The outer circumferential dimension of the opening edge 3c of the metal cap 3 may be approximately the same as the outer circumferential dimension of the capacitor element 1. Even in this case, in the manufacturing process of the capacitor 10 described later, a material having electrical insulation properties (hereinafter also referred to as insulating material) may be filled in advance in a portion (gap S1, see FIG. 3C) that may be formed between the external electrode 2 and the metal cap 3, or an insulating material such as an insulating film may be placed therein, so that an insulating material (filler member 50 described later in detail) can be interposed between the external electrode 2 and the metal cap 3.

[0059] In the above, the case where the bottom plate portion 300 and the peripheral wall portion 301 of the metal cap 3 are integrally formed has been described, but the present invention is not limited to this, and the bottom plate portion 300 and the peripheral wall portion 301 may be formed separately as long as the bottom plate portion 300 is configured to have the electrode connection portion 302. For example, the bottom plate portion 300 and the peripheral wall portion 301 may be made of separate members, and the member of the peripheral wall portion 301 may be fixed to the periphery of the bottom plate portion 300 by, for example, adhering.

[0060] There is no particular limitation on the material of the metal cap 3. The material of the metal cap 3 may be a material that is less permeable to moisture such as water vapor and gas than the external electrode 2. From this viewpoint, the material of the metal cap 3 includes, for example, copper.

[0061] Here, when the external electrode 2 is formed of metallicon, the thickness of the external electrode 2 may not be uniform as described above. In addition, both end faces (surfaces on which the external electrode 2 is formed) of the capacitor element 1 may not be flat because they include a plurality of cross sections of the first metallized film 71 and the second metallized film 72. For this reason, the dimension Lc between the capacitors 10 may vary in the capacitors 10. However, in this embodiment, the metal cap 3 has an elastically deformable electrode connection portion 302 (notch portion 303 in FIG. 1A) at the bottom plate portion 300, so that the position of the metal cap 3 can be easily adjusted, and thus the dimensional tolerance between the capacitors 10 can be absorbed. In addition, when the external electrode 2 is formed of metallicon, there may be a minute gap and a portion where the layer of the external electrode 2 is thin on the surface of the external electrode 2. If moisture such as water vapor and gas enter through such a portion, the capacitor 10 may be defective or the life of the capacitor 10 may be shortened. However, in this embodiment, the external electrode 2 is covered by the metal cap 3 and the welding member 400, preventing the external electrode 2 from coming into direct contact with the outside air, thereby preventing moisture and gas such as water vapor from entering, and further improving the moisture resistance of the capacitor 10.

[0062] The metal cap 3 may cover the boundary between the capacitor element 1 and each of the pair of external electrodes 2. In this case, the outer circumferential dimension of the opening edge 3c of the metal cap 3 is formed to be approximately the same as the outer circumferential dimension of the capacitor element 1. As described above, the external electrodes 2 are formed on both end surfaces of the capacitor element 1 by metallicon. There is a possibility that minute gaps may exist at the boundary between the capacitor element 1 and each of the external electrodes 2, and moisture such as water vapor and gas may enter through the gap. However, if the boundary is covered by the metal cap 3, the moisture resistance of the capacitor 10 can be further improved. In FIG. 1A, the metal cap 3 covers the boundary between the capacitor element 1 and the external electrodes 2 via a capacitor element protective material 51 described later.

[0063] Capacitor 10 may include bus bar 9 (see FIGS. 4 to 5B). In this case, bus bar 9 may be connected by adhering to metal cap 3, and then metal cap 3 may be connected to external electrode 2. Bus bar 9 will be described later.

[0064] The method of attaching the metal cap 3 in this embodiment will be described in detail later in the "Method of Manufacturing a Capacitor" section.

[0065] <Welding materials> The capacitor 10 preferably further includes a welding member 400. The welding member 400 joins the electrode connection portion 302 of the metal cap 3 and the external electrode 2. Therefore, the electrode connection portion 302 is brought into contact with and fixed to the external electrode 2 by the welding member 400. In this case, it is easier to ensure the electrical connection between the metal cap 3 and the external electrode 2 in the capacitor 10.

[0066] The material for producing the welded member 400 is not particularly limited as long as it does not impede the electrical connection between the electrode connection portion 302 and the external electrode 2, and may be, for example, a meltable alloy, specifically including a brazing material and a solder material. In the present disclosure, welding includes brazing and / or soldering. The welded member 400 may be formed by melting a part of the electrode connection portion 302 in the metal cap 3 and / or a part of the external electrode 2.

[0067] When the metal cap 3 has the opening 305 described above, the welding member 400 can join the electrode connection portion 302 of the metal cap 3 and the external electrode 2 through the opening 305. It is preferable that the welding member 400 seals at least a part of the opening 305 of the metal cap 3. In this embodiment, as shown in FIG. 1A , the welding member 400 covers the inclined piece 303a and the bent piece 303b in the cutout portion 303, and seals the opening 305.

[0068] A method for producing the welded member 400 in the case where the capacitor 10 has the welded member 400 will be described in detail later in the section "Method for producing a capacitor."

[0069] <Capacitor element protection material> As shown in Fig. 1A, capacitor 10 preferably includes capacitor element protective material 51. Capacitor element protective material 51 has electrical insulation properties. Capacitor element protective material 51 is a member that covers and protects at least a part of capacitor element 1. In this case, it is possible to improve the insulation reliability between capacitor element 1 and metal cap 3 and external devices. In addition, it is easy to suppress moisture absorption from the surface of capacitor element 1.

[0070] The capacitor element protective material 51 covers at least a part of the outer peripheral surface 1a of the capacitor element 1, but may also cover at least a part of the metal cap 3. Specifically, the capacitor element protective material 51 may cover the outer peripheral surface 1a of the capacitor element 1 and a part of the peripheral wall portion 301 on the outside of the metal cap 3. In this embodiment, the capacitor element protective material 51 covers the entire outer peripheral surface 1a of the capacitor element 1 and is interposed between the outer peripheral surface 1a of the capacitor element 1 and the inside of the peripheral wall portion 301 of the metal cap 3. In this case, the capacitor element protective material 51 can contribute to making it more difficult for moisture, gas, and the like to enter the capacitor element 1 and the gap between the capacitor element 1 and the peripheral wall portion 301 of the metal cap 3. This can further improve the moisture resistance of the capacitor 10. In addition, in this case, the capacitor element protective material 51 can improve the insulation reliability between the capacitor element 1 and the metal cap 3 in the capacitor 10 and an external device. However, without being limited to the above, the capacitor element protective material 51 may cover only the capacitor element 1 and may not cover the metal cap 3. In addition, the metal cap 3 may be covered by a member other than the capacitor element protective material 51 (such as a metal cap protective member (not shown) for protecting the metal cap 3).

[0071] A detailed method for producing the capacitor element protection member 51 in this embodiment will be described later in the section "Method for producing a capacitor."

[0072] The material of the capacitor element protection material 51 is not particularly limited as long as it is an electrically insulating material. It is preferable to use a material that is less permeable to moisture such as water vapor and gas than the surface of the capacitor element 1 as the material of the capacitor element protection material 51. In this case, the moisture resistance of the capacitor 10 can be further improved.

[0073] Capacitor element protective material 51 preferably contains at least one selected from the group consisting of an insulating film, a gas barrier film, and a cured product of a prepreg. In this case, moisture absorption from the surface of capacitor element 1 can be more easily suppressed, and the moisture resistance of capacitor 10 can be further improved.

[0074] The insulating film is not particularly limited as long as it is a film having insulating properties. Specific examples of the material of the insulating film include polypropylene, polyethylene, polyimide, and the like.

[0075] The gas barrier film is not particularly limited, and may be any film that has insulating properties and is difficult to transmit gases such as water vapor. As the gas barrier film, a film having a base film and a gas barrier layer formed on the base film can be used. The base film is not particularly limited. As the base film, for example, a polyethylene terephthalate (PET) film (melting point 265°C, glass transition point 80°C (TMA method)), a polyphenylene sulfide (PPS) film (melting point 280°C, glass transition point 100°C), a polyethersulfone (PES) film (glass transition point 220°C), a polyetherimide (PEI) film (glass transition point 220°C), and a polyetheretherketone (PEEK) film (melting point 340°C, glass transition point 140°C) can be used. These films are also excellent in heat resistance, so that the heat resistance of the capacitor 10 can be improved. The melting point and glass transition point are data obtained by a DSC method (heating rate: 10°C / min). The gas barrier layer is not particularly limited, but may contain at least one of silicon oxide and aluminum oxide, for example. The gas barrier layer can be formed by, for example, a vapor deposition method, a sputtering method, a plasma CVD method, or the like.

[0076] The term "cured prepreg" means that the prepreg is completely cured and in the C-stage. The C-stage is an insoluble and infusible state, which is the final stage of the curing reaction. The prepreg contains a reinforcing material and a thermosetting resin composition.

[0077] The reinforcing material is not particularly limited, but examples thereof include woven or nonwoven fabrics of organic or inorganic fibers, etc. Examples of the reinforcing material include glass cloth and nonwoven fabrics of PET fibers.

[0078] The thermosetting resin composition is not particularly limited, but a composition containing a thermosetting resin that is liquid at room temperature (25°C) before the curing reaction can be used. The thermosetting resin is not particularly limited, but examples thereof include epoxy resin, unsaturated polyester resin, and polyimide resin. Among these, epoxy resin is preferred. Epoxy resin has excellent properties such as heat resistance, chemical resistance, toughness, electrical insulation, and adhesiveness. The curing temperature of the thermosetting resin composition is preferably 120°C or lower. In this case, the influence of heat on the capacitor element 1 when curing the prepreg can be reduced. The thermosetting resin composition may contain an inorganic filler. The inorganic filler is not particularly limited, but examples thereof include silica, alumina, silicon nitride, boron nitride, magnesia, boehmite, calcium carbonate, aluminum hydroxide, and talc. The thermosetting resin composition may also contain a known curing agent and catalyst, if necessary.

[0079] As shown in FIG. 1A, the capacitor element protective material 51 may cover the boundary between the capacitor element 1 and each of the pair of external electrodes 2. That is, the end of the capacitor element protective material 51 may extend outward beyond the boundary between the capacitor element 1 and the pair of external electrodes 2. In this embodiment, the capacitor element protective material 51 particularly covers the boundary between the capacitor element 1 and each of the pair of external electrodes 2. As described above, the pair of external electrodes 2 are formed at both ends of the capacitor element 1 by metallicon. There is a possibility that a minute gap exists at the boundary between the capacitor element 1 and each of the pair of external electrodes 2, and moisture such as water vapor and gas may enter through this gap. However, if the boundary is covered by the capacitor element protective material 51, the moisture resistance of the capacitor 10 can be further improved. In FIG. 1A, the capacitor element protective material 51 covers not only the capacitor element 1 but also at least a part of the metal cap 3 (for example, the peripheral wall portion 301 on the outer side of the metal cap 3), and the capacitor element protective material 51 and the pair of metal caps 3 cover the above-mentioned boundary. Therefore, it is possible to further prevent moisture such as water vapor and gas from entering through the gap at the boundary portion.

[0080] In the above, it has been described that the capacitor element protective material 51 is integrally formed and covers both the capacitor element 1 and the metal cap 3 with one material, but a protective material that directly covers only the capacitor element 1 and a protective material that covers only the metal cap 3 may be formed separately. Even if the members that protect the capacitor element 1 and the metal cap 3 in the capacitor element protective material 51 are formed separately from each other using each material, the materials may melt when heated and mix together, resulting in an integrated structure.

[0081] In addition, in the above description, the case where the metal cap 3 is attached to the capacitor element 1 and then the capacitor element 1 is covered with the capacitor element protective material 51 has been described, but the present invention is not limited to this embodiment. For example, the capacitor element 1 may be covered with an insulating material for producing the capacitor element protective material 51, and then the metal cap 3 may be attached. In this case, a metal cap 3 having a size that fits the shape of the end of the capacitor element 1 covered with the capacitor element protective material 51 can be used.

[0082] <Filling material> The capacitor 10 preferably further includes a filling member 50. The filling member 50 preferably has electrical insulation properties. The filling member 50 is a member that is interposed and fills at least a part between the metal cap 3 and the external electrode 2 (see FIG. 1A). That is, the filling member 50 is interposed and disposed in a gap S1 (see FIG. 3C) that may be formed between the inner bottom portion 300a inside the bottom plate portion 300 of the metal cap 3 and the external electrode 2. Specifically, the filling member 50 is interposed in a gap that may be formed between the bottom plate portion 300 of the first metal cap 31 and the first metal cap 31, between the first metal cap 31 and the opposing first external electrode 21. In the capacitor 10 of this embodiment, the filling member 50 is interposed at least a part between the metal cap 3 and the external electrode 2. More specifically, in the capacitor 10, there is a portion between the external electrode 2 and the metal cap 3 where the metal cap 3 does not contact the external electrode 2, and at least a part of this portion where the metal cap 3 does not contact the external electrode 2 is filled with a filling member 50. When the capacitor 10 is provided with the filling member 50, it is possible to further prevent moisture and gas from penetrating between the metal cap 3 and the external electrode 2, and the capacitor 10 can have better moisture resistance.

[0083] The filling member 50 is particularly effective when there is almost no gap between the outer peripheral surface 1a of the capacitor element 1 and the peripheral wall portion 301 of the metal cap 3, i.e., when the outer peripheral dimensions of the capacitor element 1 and the metal cap 3 are approximately the same. In this case, it is difficult to fill a material such as resin (e.g., an insulating material for producing the capacitor element protective material 51) between the outer peripheral surface 1a of the capacitor element 1 and the inner peripheral wall portion 301 of the metal cap 3, but by interposing the filling member 50 in advance as described above, it is possible to ensure airtightness between the metal cap 3 and the external electrode 2 in the capacitor 10. In other words, the filling member 50 can contribute to improving the moisture resistance of the capacitor 10. A detailed method for producing the filling member 50 when the capacitor 10 includes the filling member 50 will be described in detail later in "Method for producing a capacitor".

[0084] The material for producing the filling member 50 is not particularly limited, but is preferably electrically insulating, and may be, for example, a resin material or the insulating material described above for the capacitor element protection material 51. When the filling member 50 is produced from a resin material, it may be, for example, a thermosetting resin material, and examples of the resin material include epoxy resin, unsaturated polyester resin, and polyimide resin.

[0085] <Metal foil> Next, the metal foil 4 will be described. In the capacitor 10 of this embodiment, the metal foil 4 preferably covers at least a part of the capacitor element protection material 51. More preferably, the metal foil 4 covers the entire side surface (outer peripheral surface 51a) of the capacitor element protection material 51. The metal foil 4 may be in contact with either the first external electrode 21 or the second external electrode 22, but preferably, as shown in FIG. 1A, the metal foil 4 is not in contact with either the first external electrode 21 or the second external electrode 22. By covering at least a part of the surface of the capacitor element 1 with the metal foil 4, it becomes easier to suppress moisture absorption from the surface of the capacitor element 1. In this embodiment, as shown in FIG. 1A, the metal foil 4 covers the capacitor element 1 via the capacitor element protection material 51. This prevents the metal foil 4 from contacting the external electrode 2, thereby suppressing short circuits. More specifically, the metal foil 4 covers the outer peripheral surface 51a of the capacitor element protective material 51 on the outside of the capacitor element protective material 51, and indirectly covers the capacitor element 1 via the capacitor element protective material 51 which covers the capacitor element protective material 51 and the outer peripheral wall portion 301 of the metal cap 3.

[0086] The material of the metal foil 4 is not particularly limited. The material of the metal foil 4 may be a material that is less permeable to moisture such as water vapor and gas than the side surface of the capacitor element 1. For example, when the wound capacitor element 7 is used, the surface of the capacitor element 1 is a dielectric film formed of polypropylene, polyethylene terephthalate, polyethylene naphthalate, polyphenyl sulfide, polystyrene, or the like. Therefore, the metal foil 4 may be a material that is less permeable to moisture such as water vapor and gas than the dielectric film. On the other hand, when the multilayer capacitor element 8 is used, the surface of the capacitor element 1 is covered with a protective film having electrical insulation. Therefore, the metal foil 4 may be a material that is less permeable to moisture such as water vapor and gas than the protective film. The material of the metal foil 4 includes, for example, copper, aluminum, iron, stainless steel, magnesium, silver, gold, nickel, and platinum. A resin-attached metal foil may be used as the metal foil 4. The resin-attached metal foil is a member in which a resin layer is provided on one side of the metal foil 4.

[0087] Note that even when capacitor 10 does not include capacitor element protective material 51, metal foil 4 covers at least a portion of capacitor element 1. In this case, metal foil 4 is preferably provided so as not to come into contact with at least one of external electrodes 2 (preferably both). In this case, for example, only the central portion of the side surface of capacitor element 1 is covered with metal foil 4 so as not to come into contact with a pair of external electrodes 2. In this case, the width of metal foil 4 is shorter than the distance from the boundary between first external electrode 21 and capacitor element 1 to the boundary between second external electrode 22 and capacitor element 1.

[0088] When the capacitor element 1 is directly covered with the metal foil 4, the distance between the boundary between the first external electrode 21 and the capacitor element 1 and the end of the metal foil 4 on the first external electrode 21 side (the distance in the direction connecting both ends of the capacitor element 1) is preferably 3 mm or more, and more preferably 5 mm or more. Similarly, the distance between the boundary between the second external electrode 22 and the capacitor element 1 and the end of the metal foil 4 on the second external electrode 22 side is preferably 3 mm or more, and more preferably 5 mm or more. In this case, the pair of external electrodes 2 and the metal foil 4 are less likely to come into contact with each other, making it easier to suppress short circuits.

[0089] After the capacitor element 1 is covered with the metal foil 4 as described above, the metal foil 4 may be covered with, for example, an insulating material (metal foil protection material 52 described below). However, from the viewpoint of suppressing short circuits, it is preferable that the capacitor element protection material 51 electrically insulates the metal foil 4 from the pair of external electrodes 2 as described above, and it is preferable that the metal foil 4 covers the capacitor element 1 via the capacitor element protection material 51.

[0090] It is preferable that the metal foil 4 is not exposed to the outside. That is, as shown in Fig. 1A, it is preferable that the metal foil 4 is disposed between the capacitor element protection material 51 and the metal foil protection material 52 so that the metal foil 4 is not exposed to the outside. In this way, by not exposing the metal foil 4 to the outside, deterioration of the metal foil 4 due to oxidation or the like can be suppressed. Furthermore, in this case, it is possible to prevent the metal foil 4 and the pair of metal caps 3 from coming into contact with each other and causing a short circuit.

[0091] <Metal foil protective material> It is preferable that capacitor 10 further includes a metal foil protection material 52. Metal foil protection material 52 covers at least a portion of metal foil 4. Preferably, as shown in Fig. 1A, metal foil protection material 52 covers the entire metal foil 4. In this case, the moisture resistance of capacitor 10 can be particularly improved.

[0092] The material of the metal foil protection material 52 can be the same as the material already described for the capacitor element protection material 51. When the capacitor 10 includes both the capacitor element protection material 51 and the metal foil protection material 52, the capacitor element protection material 51 and the metal foil protection material 52 may be made of the same material or different materials.

[0093] Like capacitor element protective material 51, metal foil protective material 52 preferably includes at least one selected from the group consisting of an insulating film, a gas barrier film, and a cured product of a prepreg. In this case, moisture absorption from the surface of capacitor element 1 can be more easily suppressed, and the moisture resistance of capacitor 10 can be further improved.

[0094] In FIG. 1A, one metal foil protective material 52 covers the entire surface of the capacitor element 1 and a part of the peripheral wall 301 (side surface) of the pair of metal caps 3, but this is not limited thereto. For example, a pair of metal foil protective materials 52 may be used to cover the peripheral wall 311 (side surface) of the first metal cap 31 and a part of the surface of the peripheral wall 311 of the first metal cap 31 of the capacitor element 1, and the peripheral wall 321 (side surface) of the second metal cap 32 and a part of the surface of the peripheral wall 321 of the second metal cap 32 of the capacitor element 1. Even in this case, the metal foil 4 and each of the pair of metal caps 3 (31, 32) are electrically insulated from each other, so that short circuits can be suppressed. However, from the viewpoint of simplifying the manufacturing process and improving the moisture resistance of the capacitor 10, it is preferable that one metal foil protective material 52 covers the entire surface of the capacitor element 1 and each of the side surfaces of the pair of metal caps 3 (31, 32) as shown in FIG. 1A.

[0095] When the capacitor 10 has a capacitor element protection material 51 and the metal foil 4 and the metal cap 3 are electrically insulated by the metal foil protection material 52, it is preferable that the metal foil 4 indirectly covers the boundary between the metal cap 3 and the capacitor element 1. That is, as shown in FIG. 1A, it is preferable that the end of the metal foil 4 extends outward from the boundary between the metal cap 3 and the capacitor element 1 and covers the boundary between the metal cap 3 and the capacitor element 1 via the metal foil protection material 52. There is a risk of a gap being present at the boundary between the metal cap 3 and the capacitor element 1, and moisture such as water vapor or gas may enter through this gap. However, as shown in FIG. 1A, the metal foil 4 covers this boundary via the metal foil protection material 52, so that the moisture resistance of the capacitor 10 can be further improved.

[0096] When the capacitor 10 does not have the metal foil protective material 52, the metal foil 4 is provided so as not to come into contact with each of the pair of metal caps 3 (31, 32). This can suppress short circuits. In this case, for example, the metal foil 4 having a width shorter than the distance from the boundary between the first metal cap 31 and the capacitor element 1 to the boundary between the second metal cap 32 and the capacitor element 1 can be used to cover only the center portion of the capacitor element 1 with the metal foil 4 so as not to come into contact with each of the pair of metal caps 3 (31, 32). The distance between the boundary between the first metal cap 31 and the capacitor element 1 and the end of the metal foil 4 on the first metal cap 31 side is preferably 3 mm or more. In addition, the distance between the boundary between the second metal cap 32 and the capacitor element 1 and the end of the metal foil 4 on the second metal cap 32 side is preferably 3 mm or more. In this case, it is easier to suppress contact between each of the pair of metal caps 3 (31, 32) and the metal foil 4. It is more preferable that the distance between the boundary between the first metal cap 31 and the capacitor element 1 and the end of the metal foil 4 on the first metal cap 31 side is 5 mm or more. It is also more preferable that the distance between the boundary between the second metal cap 32 and the capacitor element 1 and the end of the metal foil 4 on the second metal cap 32 side is 5 mm or more.

[0097] <Heat shrink tubing> As shown in FIG. 1A and FIG. 2A, the capacitor 10 preferably further includes a heat shrink tube 6. The heat shrink tube 6 covers at least a part of the capacitor element 1. Preferably, the heat shrink tube 6 indirectly covers the entire side surface (outer peripheral surface 1a) of the capacitor element 1. The heat shrink tube 6 is a resin member formed in a tube shape, and has a property of shrinking when heat is applied. For example, the heat shrink tube 6 is cut to a length approximately equal to that of the capacitor 10, and the cut heat shrink tube 6 is fitted to the capacitor 10 and heated, whereby the heat shrink tube 6 can be closely attached to the capacitor 10. The material, thickness, and size of the heat shrink tube 6 are not particularly limited. As the heat shrink tube 6, any one can be used according to the size of the capacitor 10. By further including the heat shrink tube 6 in the capacitor 10, it is possible to further suppress the intrusion of moisture such as water vapor and gas into the inside of the capacitor element 1, and the capacitor 10 can have better moisture resistance. Note that, as shown in FIG. 1A, the heat shrink tube 6 is preferably attached to the outermost layer of the capacitor 10.

[0098] In this embodiment, as shown in Fig. 1AC and Fig. 2A, a heat shrink tube 6 is provided on the outermost layer of the capacitor 10. However, as described above, the capacitor 10 does not necessarily have to include the heat shrink tube 6. That is, the capacitor 10 does not necessarily have to include the heat shrink tube 6, as shown in Fig. 2B. In Fig. 2B, the capacitor 10 is provided with a capacitor element protective material 51 that covers the entire side surface (outer peripheral surface 1a) of the capacitor element 1, a pair of metal caps 3 that cover each of the pair of external electrodes 2, a metal foil 4 that covers the capacitor element protective material 51, and a metal foil protective material 52 that covers the metal foil 4.

[0099] <Busbar> An example of a modified example of capacitor 10 according to the present embodiment will be described with reference to Figures 4 to 5B. Figure 5A is a perspective view of capacitor 10 shown in Figure 1A, further including a bus bar 9. Figure 4 is a cross-sectional view taken along line QQ in Figure 5A. Figure 5A is a perspective view of capacitor 10 including a heat shrink tube, and Figure 5B is a perspective view of capacitor 10 not including a heat shrink tube.

[0100] As shown in FIG. 4, the capacitor 10 preferably further includes a pair of bus bars 9. The pair of bus bars 9 are a first bus bar 91 and a second bus bar 92. In this embodiment, the pair of bus bars 9 are bonded to each of the pair of metal caps 3, and the pair of bus bars 9 and the pair of external electrodes 2 can be electrically connected via the pair of metal caps 3. Specifically, the first bus bar 91 is bonded to the first metal cap 31 to electrically connect them. Next, the first metal cap 31 to which the first bus bar 91 is bonded is attached to the capacitor element 1 including the first external electrode 21 to electrically connect the first metal cap 31 and the first external electrode 21. Similarly, the second bus bar 92 is bonded to the second metal cap 32 to electrically connect them. Next, the second metal cap 32 to which the second bus bar 92 is bonded is attached to the capacitor element 1 including the second external electrode 22 to electrically connect the second metal cap 32 and the second external electrode 22. In this way, the capacitor 10 including the bus bar 9 can be obtained.

[0101] The pair of bus bars 9 is not particularly limited, and may be, for example, copper or a copper alloy formed into a plate shape. The method for bonding the pair of bus bars to each of the pair of external electrodes 2 is not particularly limited, and examples of the method include bonding by solder welding, resistance welding, laser welding, ultrasonic welding, etc. From the viewpoint of preventing short circuits, the pair of bus bars 9 are not in contact with the metal foil 4, and are electrically insulated from the metal foil 4.

[0102] In the above description, the bus bar 9 is bonded to the metal cap 3 and then electrically connected to the external electrode 2, but the order in which the bus bar 9 is connected to the metal cap 3 is not limited to this, and for example, the metal cap 3 may be attached to the capacitor element 1 including the external electrode 2 and then the bus bar 9 may be bonded to the metal cap 3. That is, for example, the first metal cap 31 may be attached to the first external electrode 21 and then the first bus bar 91 may be bonded to the first metal cap 31. The same applies to the order in which the second bus bar 92 is connected to the second metal cap, and the second metal cap 32 may be attached to the second external electrode 22 and then the second bus bar 92 may be bonded to the second metal cap 32.

[0103] <Capacitor manufacturing method> Next, a specific method for manufacturing the capacitor 10 of this embodiment will be specifically described with reference to Figures 3A to 3G. For the method for manufacturing the capacitor 10 of this embodiment, the description of each component that may be included in the capacitor 10 described above can be appropriately referred to.

[0104] The method for manufacturing the capacitor 10 of this embodiment includes a placement step and a mounting step.

[0105] <<Placement process>> First, a capacitor element 1 and a metal cap 3 are prepared (see FIG. 3A). The capacitor element 1 may have a pair of external electrodes 2 at both ends. The metal cap 3 may be the metal cap 3 described above. That is, the metal cap 3 has a bottom plate portion 300 facing the pair of external electrodes, and an elastically deformable electrode connection portion 302 is formed on an inner bottom portion 300a of the bottom plate portion 300. The electrode connection portion 302 in the metal cap 3 of this embodiment is a notch portion 303. Therefore, an opening 305 is formed in the metal cap 3, and more specifically, the opening 305 includes a notch groove 306 (see FIG. 3E).

[0106] In this embodiment, the metal cap 3 has an opening edge 3c with a larger outer circumferential dimension than the end of the capacitor element 1. However, the shape of the metal cap 3 is not limited to the above-mentioned shape, and may be any shape that allows attachment to the end of the capacitor element 1 so as to cover the external electrode 2.

[0107] Next, the capacitor element 1 and the pair of metal caps 3 are placed in a mold 610. The mold 610 is, for example, a device such as a compression molding machine. The mold 610 includes a lower mold 620 and a pair of upper molds 630 (see FIGS. 3B to 3D). The mold 610 has appropriate dimensions so that a capacitor 10 having a predetermined dimension Lc can be manufactured. For example, the inner dimension Li of the mold 610 (for example, the lower mold 620) can be appropriately adjusted according to the dimensions for obtaining a capacitor 10 having the predetermined dimension Lc.

[0108] The lower mold 620 may have, for example, a bottomed cylindrical shape having a bottom plate and a peripheral wall surrounding the bottom plate, and an opening on the upper side in the vertical direction. The peripheral wall of the lower mold 620 may have an opening at a portion where the side surface of the bottom plate portion 300 side of the metal cap 3 contacts. More specifically, the lower mold 620 may be formed in a U-shape in a side view (see Figs. 3E to 3G). In this case, at least a part of the outer bottom portion 300b of the metal cap 3 can be seen from the side of the mold 610. However, the shape of the lower mold 620 is not limited to the above. Similarly, the upper mold 630 may have, for example, a bottomed cylindrical shape having a bottom plate and a peripheral wall surrounding the bottom plate, and an opening on the upper side in the vertical direction. The peripheral wall of the upper mold 630 may have an opening at a portion where the side surface of the bottom plate portion 300 side of the metal cap 3 contacts. That is, the upper mold 630 may be formed in a U-shape when viewed from the side (see FIGS. 3E to 3G). Specifically, when arranging the capacitor element 1 and the metal cap 3 in the mold 610, as shown in FIG. 3B, the pair of metal caps 3 are placed on both ends of the capacitor element 1 so as to cover the capacitor element 1 with the peripheral wall parts 301 of each, and the metal caps 3 are placed in the lower mold 620 while being pressed, and positioned. Since the metal cap 3 has an elastically deformable electrode connection part 302, the metal cap 3 can be brought into contact with the external electrode 2 and elastically deformed to adjust the distance L between the outermost parts of the pair of metal caps to match the inner dimension Li of the mold 610 (lower mold 620), and thus positioned. For example, if the distance L between the outermost parts of the pair of metal caps 3 before placing the metal caps 3 on the capacitor element 1 in the mold 610 is larger than the inner dimension Li of the mold 610, the metal caps 3 can be pressed in when being placed, so that the distance L between the outermost parts coincides with the inner dimension Li of the mold 610. 3B, the distance L between the outermost sides of the pair of metal caps 3 is twice as large as the distance d, but by pressing in and elastically deforming each of the electrode connection portions 302 of the pair of metal caps 3 and arranging them, the distance L between the outermost sides can be contracted by the amount of change 2d, thereby matching the inner dimension Li of the mold 610. Thus, in this embodiment, positioning can be easily performed when arranging the pair of metal caps 3 on the capacitor element 1 in the arrangement step.

[0109] Next, the upper die 630 is fixed so as to cover the capacitor element 1 and the pair of metal caps 3 arranged on the lower die 620. The inner dimension of the upper die 630 is also approximately the same as the inner dimension Li of the lower die 620. In addition, it is preferable to arrange a damming member 621 in a part of the gap between the surfaces of the lower die 620 that contact the peripheral wall portion 301 on the outside of the metal cap 3. Similarly, it is preferable to arrange a damming member 632 in a part of the gap between the surfaces of the upper die 630 that contact the peripheral wall portion 301 on the outside of the metal cap 3. In this case, when filling a material (e.g., a resin material) for forming the capacitor element protection material 51 described later, the resin material can be prevented from flowing into the outer bottom portion 300b on the outside of the bottom plate portion 300 of the metal cap 3. The damming members 621 and 632 may be formed from an appropriate material.

[0110] The upper mold 630 is open on the lower side in the vertical direction. The upper side (upper portion) of the upper mold 630 in the vertical direction may be partially open. In this case, the opening can be used as an injection port 631 for filling, for example, a resin material described later. As with the lower mold 620 described above, the upper mold 630 preferably has a damming member 632 disposed in a portion between the surfaces that come into contact with the peripheral wall portion 301 on the outside of the metal cap 3. In this case, when filling the material for forming the capacitor element protection material 51, the resin material can be prevented from flowing into the outer bottom portion 300b on the outside of the bottom plate portion 300 of the metal cap 3.

[0111] In this manner, in this embodiment, the dimensions of the capacitor 10 can be adjusted in the arrangement step. Therefore, the dimension Lc of the manufactured capacitor 10 can be made constant. Note that the inner dimension Li of the mold 610 in this embodiment is constant for each mold used to manufacture the capacitor 10. Therefore, the distance L between the outermost sides of the pair of metal caps 3 whose positions have been adjusted approximately coincides with the inner dimension Li of the mold 610, and the inner dimension Li of the mold 610 becomes the dimension Lc of the capacitor 10.

[0112] <<Installation process>> As described above, in this embodiment, it is preferable to include welding the external electrode 2 and the electrode connection portion 302 of the metal cap 3 after placing the capacitor element 1 and the pair of metal caps 3 in the mold 610. Specifically, as shown in FIG. 3F, for example, a welding material is poured from the side of the mold 610 through the opening 305 formed in the bottom plate portion 300 of the metal cap 3, thereby welding the notch portion 303 and the external electrode 2. In this way, a welded member 400 can be produced between the metal cap 3 and the external electrode 2. In particular, in this embodiment, the welded member 400 seals the opening 305 including the notch groove 306 in the metal cap 3 (see FIGS. 3E to 3G). The welding is not limited to the above method, and any appropriate welding method can be adopted, and examples of the welding include adhesion methods such as resistance welding, ultrasonic welding, and laser welding.

[0113] In this embodiment, the above-described welding of the external electrode 2 and the electrode connection portion 302 of the metal cap 3 is performed before filling with an insulating resin material, which will be described later. In this case, it is possible to produce a capacitor 10 with improved moisture resistance while maintaining good electrical connection between the external electrode 2 and the metal cap 3 in the capacitor 10.

[0114] Next, in a state where the capacitor element 1 and the pair of metal caps 3 are positioned in the mold 610 (see FIG. 3B or 3C), an insulating resin material (hereinafter also referred to as resin material R) for producing the capacitor element protection material 51 is injected from an injection port 631 of the upper mold 630 to fill the mold 610 (see FIG. 3D). Then, the filled resin material R is appropriately heated while compressing the mold 610 as necessary to harden the resin material R. The resin material R is, for example, a thermosetting resin. In this manner, the capacitor element protection material 51 covering the outer peripheral surface 1a of the capacitor element 1 can be produced. In this embodiment, the capacitor element protection material 51 also covers a part of the peripheral wall portion 301 on the outer side of the metal cap 3. In addition, if the resin material R is filled in the gap S1 (see FIG. 3D) that may be formed between the metal cap 3 and the external electrode 2, the filling member 50 in which the capacitor element protection material 51 is interposed between the external electrode 2 and the metal cap 3 can be formed. In this case, the filling member 50 is included in the capacitor element protection material 51. That is, the capacitor element protection material 51 may be interposed at least partially between the external electrode 2 and the metal cap 3.

[0115] In addition, the capacitor element protection material 51 does not necessarily have to be prepared by filling it with resin material R, but may be prepared by previously covering the outer surface 1a of the capacitor element 1 with an insulating material such as an insulating film, so that the capacitor element 1 is used in the placement process in a state where it is covered with the capacitor element protection material 51.

[0116] In this manner, capacitor 10 is obtained in which a pair of metal caps 3 are attached to both ends of capacitor element 1. Capacitor 10 including metal foil 4, metal foil protective material 52, and heat shrink tube may each be produced by the methods already described.

[0117] Incidentally, in producing the capacitor element protection material 51, if the outer circumferential dimensions of the metal cap 3 and the capacitor element 1 are substantially the same, when the capacitor element 1 is covered with the metal cap 3, almost no gap is formed between the peripheral wall portion 301 of the metal cap 3 and the outer circumferential surface 1a of the capacitor element 1. In this case, it may be difficult to fill the resin material R up to the gap S1 that may be formed between the metal cap 3 and the external electrode 2. This may result in a decrease in moisture resistance between the metal cap 3 and the external electrode 2.

[0118] Therefore, in the arrangement step of the method for manufacturing the capacitor 10 described above, it is preferable to interpose a filling material at least partially between the bottom plate portion 300 of the metal cap 3 and the external electrode 2 facing the bottom plate portion 300. In this case, the filling member 50 can be produced from the filling material. This makes it possible to manufacture the capacitor 10 including the filling member 50. Specifically, by filling a material for producing the filling member 50 (also called a filling material) in advance into the gap S1 (see FIG. 3D) that may be formed when the metal cap 3 is attached to the capacitor element 1, the filling member 50 can be interposed at least partially between the external electrode 2 and the metal cap 3 (see FIG. 3G). Then, the metal cap 3 is attached to the capacitor element 1, and the filling material is melted by heating, and then hardened to form the filling member 50. The filling member 50 can be said to be a protective material that covers a part of the external electrode 2. Note that even when the filling material is interposed in advance, it may be used in combination with the method for producing the capacitor element protective material 51 described above. For example, even if the peripheral dimension of the metal cap 3 is larger than the peripheral dimension of the capacitor element 1, before filling the resin material R, a filling material may be interposed in advance in at least a portion between the bottom plate portion 300 of the metal cap 3 and the external electrode 2 facing the bottom plate portion 300, and then the resin material R may be filled.

[0119] The manufacturing method of the capacitor 10 described above is a specific example, and is not limited to the above. For example, in the arrangement step, when the capacitor element 1 and the pair of metal caps 3 are arranged on the lower mold 620, the capacitor element 1 is arranged in a state in which the pair of metal caps 3 are covered on both ends of the capacitor element 1, but the method is not limited to this. For example, the first metal cap 31 is arranged on the lower mold 620, and then the first external electrode 21 is brought into contact with the electrode connection portion 312 of the first metal cap 31 while the outer peripheral surface 1a of the capacitor element 1 is accommodated in the first metal cap 31. Next, the second metal cap 32 is pressed against the outer peripheral surface 1a of the capacitor element 1 from the second external electrode 22 side of the capacitor element 1 so as to cover it, thereby covering it. In this case, even if the outermost interval L between the pair of metal caps 3 is smaller than the inner dimension Li of the mold 610, the electrode connection portion 302 of the metal cap 3 is elastically deformed, so that the outermost interval L between the pair of metal caps 3 can be adjusted to match the inner dimension Li of the mold 610.

[0120] Furthermore, for example, in FIG. 3B, the amount of change d in contraction at the electrode connection portions 302 of a pair of metal caps 3 is the same for each metal cap 3, but this is not limited thereto, and the amount of change in deformation due to contraction may be different between the first metal cap 31 and the second metal cap 32.

[0121] In addition, the above describes the case where capacitor 10 includes a capacitor element 1, a pair of external electrodes 2 (21, 22), a pair of metal caps 3 (31, 32), a filling member 50, a capacitor element protective material 51, and a welding member 400, but is not limited to the above and can be appropriately modified to include any appropriate element that capacitor 10 may include.

[0122] 3. Aspects As is apparent from the above-described embodiment and modified examples, the present disclosure includes the following aspects. In the following, reference symbols are given in parentheses only to clarify the correspondence with the embodiment.

[0123] A capacitor (10) according to a first aspect includes a capacitor element (1), a pair of external electrodes (2 (21, 22)), and a pair of metal caps (3 (31, 32)). The pair of external electrodes (2 (21, 22)) are provided on both ends of the capacitor element (1). The metal caps (3 (31, 32)) cover each of the pair of external electrodes (2 (21, 22)). The metal cap (3) has a bottom plate portion (300) and a peripheral wall portion (301). The bottom plate portion (300) faces the external electrodes (2). The peripheral wall portion (301) covers at least a portion of the outer periphery of the capacitor element. An electrode connection portion (302) is provided on an inner bottom portion (300a) on the inside of the bottom plate portion (300). The electrode connection portion (302) is elastically deformable and is in contact with the external electrode (2).

[0124] According to the first aspect, dimensional variations are unlikely to occur, and in this case, the capacitor (10) can be made lighter and have high moisture resistance.

[0125] In the capacitor (10) of the second aspect, in the first aspect, the electrode connection portion (302) is a notch portion (303) in which a portion of the outer bottom portion (300b) side of the bottom plate portion (300) is cut out toward the inner bottom portion (300a) side.

[0126] According to the second aspect, it is possible to provide high moisture resistance and to make it more difficult for dimensional variations to occur. In this case, the connection between the metal cap 3 and the external electrode 2 can be easily secured.

[0127] In the capacitor (10) according to the third aspect, in the first or second aspect, the metal cap (3) has an opening (305) that penetrates from the outer bottom portion (300b) to the inner bottom portion (300a).

[0128] According to the third aspect, the device has high moisture resistance and is less likely to have dimensional variations, and in this case, the connection between the metal cap (3) and the external electrode (2) is easily secured.

[0129] The capacitor (10) according to a fourth aspect is in any one of the first to third aspects, further comprising a welding member (400) that joins the electrode connection portion (302) and the external electrode (2).

[0130] According to the fourth aspect, the bonding strength between the metal cap (3) and the external electrode (2) in the capacitor (10) can be further increased.

[0131] In a capacitor (10) according to a fifth aspect, in the fourth aspect, the welding member (400) seals at least a portion of the opening (305).

[0132] According to the fifth aspect, the moisture resistance of the capacitor (10) can be further improved.

[0133] A capacitor (10) according to a sixth aspect is in any one of the first to fifth aspects, and further comprises a filling member (50) interposed between the metal cap (3) and the external electrode (2).

[0134] According to the sixth aspect, the moisture resistance of the capacitor (10) can be further improved.

[0135] The capacitor (10) according to a seventh aspect is in any one of the first to sixth aspects, and further includes a capacitor element protection material (51) that covers at least a part of the outer circumferential surface (1a) of the capacitor element (1).

[0136] According to the seventh aspect, the capacitor element protection material (51) can improve the insulation reliability between the capacitor element (1) and the metal cap (3) and the external device. In addition, moisture absorption from the surface of the capacitor element (1) can be easily suppressed.

[0137] In a capacitor (10) according to an eighth aspect, in the seventh aspect, the capacitor element protection material (51) includes at least one material selected from the group consisting of an insulating film, a gas barrier film, and a cured product of a prepreg.

[0138] According to the eighth aspect, it is possible to further improve the moisture resistance of the capacitor 10. Also, it is possible to further improve the insulation reliability between the capacitor element 1 and the metal cap 3 in the capacitor 10 and the external device.

[0139] The capacitor (10) according to a ninth aspect is the capacitor of the seventh or eighth aspect, further comprising a metal foil (4) covering at least a portion of the capacitor element protection material (51).

[0140] According to the ninth aspect, the moisture resistance of the capacitor (10) can be further improved.

[0141] The capacitor (10) according to a tenth aspect is the ninth aspect, further comprising a metal foil protective material (52) that covers at least a part of the metal foil (4) on the outside of the metal foil (4).

[0142] According to the tenth aspect, it is possible to further improve the moisture resistance of the capacitor 10. Also, it is possible to further improve the insulation reliability between the capacitor element 1 and the metal cap 3 in the capacitor 10 and the external device.

[0143] In a capacitor (10) according to an eleventh aspect, in the tenth aspect, the metal foil protective material (52) includes at least one material selected from the group consisting of an insulating film, a gas barrier film, and a cured product of a prepreg.

[0144] According to the eleventh aspect, the moisture resistance of the capacitor (10) can be further improved.

[0145] A capacitor (10) according to a twelfth aspect is any one of the first to eleventh aspects, further comprising a heat shrink tube (6) covering at least a portion of the capacitor element (1).

[0146] According to the twelfth aspect, the moisture resistance of the capacitor (10) can be further improved, and the insulation reliability between the capacitor (10) and an external device can be further improved.

[0147] A method for manufacturing a capacitor (10) according to a thirteenth aspect includes an arrangement step and a mounting step. The arrangement step includes arranging a capacitor element (1) having a pair of external electrodes (2 (21, 22)) at both ends and a pair of metal caps (3 (31, 32)) having bottom plate portions (300 (310, 320)) facing the pair of external electrodes (2 (21, 22)) in a mold (601). The mounting step includes mounting each of the pair of metal caps (3 (31, 32)) to each of the pair of external electrodes (2 (21, 22)). The metal cap (3) faces the external electrode (2) and has an electrode connection portion (302) that is elastically deformable. The arrangement step includes bringing the metal cap (3) and the external electrode (2) into contact with each other by elastically deforming the electrode connection portion (302).

[0148] According to the thirteenth aspect, the capacitor (10) can be produced with high moisture resistance and with less variation in dimensions between capacitors (10).

[0149] In a fourteenth aspect, in the method for manufacturing a capacitor (10) of the thirteenth aspect, the positioning step further includes adjusting and positioning the pair of metal caps (3 (31, 32)) by elastically deforming the electrode connection portion (302).

[0150] According to the fourteenth aspect, the dimensions of a given capacitor (10) can be easily adjusted, and therefore, the capacitors (10) can be manufactured with less variation in dimensions between the capacitors (10).

[0151] The method for manufacturing a capacitor (10) in accordance with a fifteenth aspect is the thirteenth or fourteenth aspect, and further includes, in the placement step, interposing a filling material at least partially between the bottom plate portion (300) of the metal cap (3) and the external electrode (2) facing the bottom plate portion (300).

[0152] According to the fifteenth aspect, a capacitor (10) having even better moisture resistance can be produced.

[0153] A method for manufacturing a capacitor (10) according to a sixteenth aspect is any one of the thirteenth to fifteenth aspects, in which an opening (305) is formed in a bottom plate portion (300) of the metal cap (3). The arranging step includes welding the electrode connection portion (302) to the external electrode (2) through the opening (305).

[0154] According to the sixteenth aspect, the strength of the electrical connection in the capacitor (10) can be increased, and variations between the capacitors (10) can be more unlikely to occur.

[0155] A seventeenth aspect of the present invention relates to a method for producing a capacitor (10) according to the sixteenth aspect, and in the mounting step, includes filling the die (610) with resin. The filling of the resin is performed before the welding.

[0156] According to the seventeenth aspect, the capacitor element protection material (51) can be produced after joining the external electrode (2) and the metal cap (3), so that a capacitor (10) with improved moisture resistance can be produced while maintaining good electrical connection between the external electrode (2) and the metal cap (3). [Explanation of symbols]

[0157] 10 Capacitor 1 Capacitor element 2 External electrode 3 Metal Cap 300 Bottom plate part 300a inner bottom 300b outer bottom 301 Peripheral wall section 302 Electrode connection part 303 Notch 305 Aperture 400 Welding materials 4 Metal foil 50 Filler material 51 Capacitor element protection material 52 Metal foil protection material 6 Heat shrink tubing 610 Molds

Claims

1. A capacitor element; a pair of external electrodes provided on both ends of the capacitor element; a metal member covering at least one of the pair of external electrodes, the metal member has a bottom plate portion facing the external electrode, a cantilevered electrode connection portion that contacts the external electrode is provided on the bottom plate portion, a welding member for joining the electrode connection portion and the external electrode, The welding member seals at least a portion of the opening of the metal member. Capacitor.

2. The electrode connection portion is A bent piece provided in a tip region of the electrode connection portion; a tilted piece that connects the main body of the bottom plate portion and the bent piece, The electrode connection portion is bent between the inclined piece and the bent piece. The capacitor of claim 1 .

3. The bent piece has a flat surface, The electrode connection portion is connected to the external electrode on the flat surface. The capacitor of claim 2.

4. The bent piece is substantially parallel to the external electrode. The capacitor according to claim 2 or 3.

5. The length of the bent piece in the extension direction is longer than the length of the inclined piece in the extension direction. The capacitor according to any one of claims 2 to 4.

6. The electrode connection portion is formed by a notch portion formed by cutting out a part of the bottom plate portion. A capacitor according to any one of claims 1 to 5.

7. The cutout portion is a through hole penetrating the metal member. The capacitor of claim 6.

8. The electrode connection portion is elastically deformable. A capacitor according to any one of claims 1 to 7.

9. The metal member has a peripheral wall portion that covers at least a part of an outer periphery of the capacitor element. A capacitor according to any one of claims 1 to 8.

10. a pair of the metal members covering the pair of external electrodes, A capacitor according to any one of claims 1 to 9.

11. Further comprising a filler member interposed between the metal member and the external electrode. A capacitor according to any one of claims 1 to 10.

12. Further comprising a capacitor element protective material covering at least a portion of an outer peripheral surface of the capacitor element. A capacitor according to any one of claims 1 to 11.

13. The capacitor element protective material includes at least one selected from the group consisting of an insulating film, a gas barrier film, and a cured product of a prepreg. The capacitor of claim 12.

14. Further comprising a metal foil covering at least a portion of the capacitor element protection material. The capacitor according to claim 12 or 13.

15. Further comprising a metal foil protective material covering at least a portion of the metal foil on an outer side of the metal foil. The capacitor of claim 14.

16. The metal foil protective material includes at least one selected from the group consisting of an insulating film, a gas barrier film, and a cured product of a prepreg. The capacitor of claim 15.

17. Further comprising a heat shrink tube covering at least a portion of the capacitor element. A capacitor according to any one of claims 1 to 16.

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