JP2020088342A - Electrolytic capacitor - Google Patents

Abstract

To make the positioning of an anode wire easier.SOLUTION: An electrolytic capacitor comprises: a capacitor element; an anode lead terminal; a cathode lead terminal; and an outer packaging body. The capacitor element has an anode part having an anode body and an anode wire. The anode lead terminal has: a flat face part located along an extending direction of the anode wire; a first rising part rising up toward a direction intersecting the flat face part from at least part of one first side of the flat face part along the extending direction; a second rising part rising toward a direction of intersecting the flat face part from at least part of the other second side along an extending direction of the flat face part; a first arm part extending in a direction from at least part of the first rising part toward the second side; and a second arm part extending in a direction from at least part of the second rising part toward the first side. In the electrolytic capacitor, a first end of the first arm part on the side of the second side and a second end of the second arm part on the side of the first side are spaced apart from each other so as to face each other, and the anode wire is put in touch with the first end and the second end.SELECTED DRAWING: Figure 1

Description

The present invention relates to electrolytic capacitors, and more particularly to improvements in anode lead terminals.

Electrolytic capacitors have a small equivalent series resistance (ESR) and excellent frequency characteristics, and are therefore mounted in various electronic devices. An electrolytic capacitor usually includes a capacitor element having an anode part and a cathode part, an anode lead terminal electrically connected to the anode part, a cathode lead terminal electrically connected to the cathode part, and an outer body covering the capacitor element. Have. The anode part has an anode body and an anode wire extending from the anode body.

The anode wire is erected from approximately the center of one surface of the anode body. In order to join such an anode wire and an anode lead terminal, in Patent Documents 1 and 2, a rising portion is formed in the anode lead terminal.

JP, 2010-109005, A International Publication No. 2017/056492 Pamphlet

2. Description of the Related Art In recent years, with downsizing and height reduction of electronic devices, there is a demand for downsizing of electrolytic capacitors mounted on substrates inside electronic devices. Along with the miniaturization of electrolytic capacitors, it is also necessary to make the anode lead terminals smaller. Therefore, when joining the anode wire and the anode lead terminal, it is difficult to determine the position of the anode wire, and the productivity is likely to be reduced.

A first aspect of the present invention, a capacitor element having an anode portion and a cathode portion, an anode lead terminal electrically connected to the anode portion, a cathode lead terminal electrically connected to the cathode portion, An outer casing that covers the capacitor element is provided, and the anode portion has an anode body and an anode wire extending from the erected surface of the anode body, and the anode lead terminal is the anode wire of the anode wire. A plane portion existing along the extending direction; a first rising portion rising from at least a part of one first side of the plane portion along the extending direction in a direction intersecting the plane portion; and the plane portion. A second rising portion rising from at least a part of the other second side along the extending direction in a direction intersecting the plane portion, and a direction from at least a part of the first rising portion toward the second side. And a second arm portion extending in a direction toward the first side from at least a part of the second rising portion, when viewed from a normal direction of the planting surface, The first end portion of the first arm portion on the second side side and the second end portion of the second arm portion on the first side side are arranged so as to face each other and are spaced apart from each other. The wire relates to an electrolytic capacitor in contact with the first end and the second end.

According to the present invention, positioning of the anode wire is facilitated.

It is a perspective view which shows typically the electrolytic capacitor which concerns on one Embodiment of this invention. It is a perspective view which expands and shows the principal part of the electrolytic capacitor which concerns on one Embodiment of this invention. It is the top view which looked at the electrolytic capacitor of FIG. 2A from the normal line direction of the planting surface. It is a perspective view which expands and shows the principal part of the electrolytic capacitor which concerns on other embodiment of this invention. It is the top view which looked at the electrolytic capacitor of FIG. 3A from the normal line direction of the planting surface. It is a perspective view which shows typically the principal part of the anode lead terminal which concerns on other embodiment of this invention. It is a perspective view which shows typically the principal part of the anode lead terminal which concerns on other embodiment of this invention. It is a sectional view showing the electrolytic capacitor concerning one embodiment of the present invention typically. 6 is a flowchart showing a method for manufacturing an electrolytic capacitor according to an embodiment of the present invention. It is a top view showing a conductor plate which is a material of an anode lead terminal, and a planned punching line. It is a perspective view which shows typically the precursor of the anode lead terminal in which the rising part was formed. It is a perspective view which shows typically the precursor of the anode lead terminal in which the arm part was formed. FIG. 6 is a perspective view showing a state where an anode wire is sandwiched by two arm portions.

The electrolytic capacitor according to the present embodiment includes a capacitor element having an anode part and a cathode part, an anode lead terminal electrically connected to the anode part, a cathode lead terminal electrically connected to the cathode part, and a capacitor element. And an exterior body that covers the. The anode part has an anode body and an anode wire extending from a planting surface of the anode body.

The anode lead terminal includes a flat surface portion, two rising portions rising from the flat surface portion, and arm portions extending from the two rising surfaces along the planting surface, respectively. The flat portion exists along the extending direction A of the anode wire. One of the rising portions (first rising portion) rises in a direction intersecting with the flat portion from at least a part of one first side along the extending direction A of the flat portion. The other of the rising portions (second rising portion) rises in a direction intersecting with the flat portion from at least a part of the other second side along the extending direction A of the flat portion. One of the arm portions (first arm portion) extends from at least a part of the first rising portion in the direction toward the second side. The other of the arm portions (second arm portion) extends from at least a part of the second rising portion in the direction toward the first side.

When viewed from the direction normal to the planting surface, the first end of the first arm portion on the second side and the second end of the second arm portion on the first side are facing each other. Are not in contact and are spaced apart. The anode wire is in contact with both the first end and the second end. That is, at least a part of the anode wire is arranged in the gap formed between the first end portion and the second end portion. Therefore, the anode wire is positioned by the gap and the movement thereof is suppressed.

As described above, the anode lead terminal of the present embodiment has the two arm portions arranged along the planting surface, and the arm portions abut each other so as not to contact each other. However, the position of the anode wire can be easily determined. In addition, since the anode wire and the anode lead terminal can be welded in this state, the connection reliability is improved.

The first end portion of the first arm portion is an end portion on the second side when the first arm portion is viewed from the normal line direction of the planting surface. When the first arm portion has a flat plate shape, the first end portion may be an end face and an edge arranged along the thickness direction of the first arm portion. The end surface is, for example, a cut surface. The edge is, for example, an intersection of two cut surfaces. The second end of the second arm portion is similarly defined.

According to this embodiment, the width of the gap formed by the two arms can be easily adjusted. The contact position between the anode wire and the anode lead terminal can be arbitrarily set by adjusting the size of this gap. For example, when the first arm portion is viewed from the normal line direction of the planting surface, the width Lg of the gap in the plane direction of the plane portion (hereinafter, sometimes referred to as width direction B) is set to the extension portion of the anode wire ( When the diameter D of the second portion) in the width direction B is substantially the same (Lg=D), the second portion of the anode wire can be sandwiched between the first end portion and the second end portion.

When the width Lg of the gap is smaller than the diameter D of the second portion of the anode wire (Lg<D), the second portion of the anode wire is divided into the edge at the first end of the first arm portion and the second arm portion. Can be supported by contacting the edge at the second end of the. At this time, a part of the end surface of the anode wire is arranged in the gap between the first end portion and the second end portion.

The width Lg is a length of a line segment connecting a contact point between the first end of the first arm portion and the anode lead terminal and a contact point between the second end of the second arm portion and the anode lead terminal.

The angle θ _2A formed by the flat surface portion and the first rising portion is not particularly limited, and depending on the size of the gap, the height from the flat surface portion to the second portion of the anode wire, the size of each arm portion, and the like, It may be set appropriately. The angle θ _2A may be, for example, 75 degrees or more and 100 degrees or less, and may be 85 degrees or more and 95 degrees or less. The angle θ _2B formed by the flat surface portion and the second rising portion is not particularly limited, and may be, for example, 75 degrees or more and 100 degrees or less, or 85 degrees or more and 95 degrees or less. The angle θ _2A and the angle θ _2B may be the same or different.

The angle θ _3A formed by the first rising portion and the first arm portion is not particularly limited, and may be appropriately set according to the positional relationship between the second portion of the anode wire and the first rising portion and the like. The angle θ _3A may be, for example, 75 degrees or more and 100 degrees or less, and may be 85 degrees or more and 95 degrees or less. The angle θ _3B formed by the second rising portion and the second arm portion is not particularly limited, and may be, for example, 75 degrees or more and 100 degrees or less, or 85 degrees or more and 95 degrees or less. The angle θ _3A and the angle θ _3B may be the same or different.

The shape of the first arm portion is not particularly limited as long as it extends from the first side toward the second side when viewed in the normal direction of the plane portion. When viewed from the direction normal to the plane portion, the first arm portion may be a straight line, a curved line, or a combination of a straight line and a curved line. For example, the tip of the first arm portion may be bent. Similarly, the second arm portion may extend from the second side toward the first side, and the shape thereof is not particularly limited.

The first arm portion extending from the first side toward the second side means that the middle point of the first end portion of the first arm portion and the end on the first side side when viewed from the normal direction of the plane portion. The angle formed by the straight line connecting the center point of the part and the width direction B is 0 degrees or more and 30 degrees or less. The second arm portion extending from the second side toward the first side means that when viewed from the normal direction of the plane portion, the middle point of the second end portion of the second arm portion and the end on the second side side. The angle formed by the straight line connecting the center point of the part and the width direction B is 0 degrees or more and 30 degrees or less.

Both the first arm portion and the second arm portion may have a flat plate shape. At this time, when one main surface of each is opposed to the erected surface of the anode body, the first end portion of the first arm portion and the second end portion of the second arm portion extend in the direction normal to the plane portion. A gap is formed. Therefore, regardless of the height from the flat surface portion to the second portion of the anode wire, the second portion of the anode wire can be sandwiched at any position in the gap. Therefore, the anode lead terminal of this embodiment can be applied to capacitor elements having various thicknesses.

However, the height HH1 from the flat portion of the first end portion to the farthest point is set to be equal to or higher than the height HLw from the flat portion of the second portion of the anode wire to the closest point (HH1≧HLw), and the first end portion The height HL1 from the plane part to the nearest point is set to be equal to or less than the height HHw from the plane part of the second portion of the anode wire to the farthest point (HL1≦HHw). This allows the first end and the second portion of the anode wire to contact. The height HH2 from the plane portion of the second end portion to the farthest point and the height HL2 from the plane portion of the second end portion to the closest point similarly satisfy HH2≧HLw and HL2≦HHw. This allows the second end to contact the second portion of the anode wire. The height HH1 and the height HH2 may be the same or different. The height HL1 and the height HL2 may be the same or different.

The gap extending in the normal direction of the flat surface portion means that the angle formed by the center line passing through the center of the first end portion and the second end portion and the normal line of the flat surface portion is 0 degree or more and 30 degrees or less. Say. The center line, when viewed from the normal direction of the planting surface, draws three line segments extending in the width direction B that connects the first end portion and the second end portion, It is a straight line formed by connecting points.

FIG. 1 is a perspective view schematically showing an example of the electrolytic capacitor according to the present embodiment. In FIG. 1, the exterior body is omitted for convenience.
The electrolytic capacitor 20 includes a capacitor element 10 having an anode part and a cathode part, an anode lead terminal 13 electrically connected to the anode part, a cathode lead terminal (not shown) electrically connected to the cathode part, and a capacitor. And an exterior body (not shown) that covers the element. The anode part includes an anode body and an anode wire 2 (2b) extending from the erected surface 1X of the anode body.

The anode lead terminal 13 includes a flat surface portion 131 that exists along the extending direction A of the extending portion (second portion 2b) of the anode wire 2. A part of the flat surface portion 131 is exposed from the exterior body and used as a terminal connected to an external device. When the flat surface portion 131 is viewed from the normal direction, one end portion of the flat surface portion 131 in the extending direction A is arranged so as to overlap the capacitor element 10. However, an insulating material (for example, an outer package) is interposed between the flat surface portion 131 and the capacitor element 10 so that they are not electrically connected.

The anode lead terminal 13 includes a first rising portion 132A that rises in a direction intersecting with the flat surface portion 131 from a part of one side (first side 131a) along the extending direction A of the flat surface portion 131. The first arm portion 133A extends from a part of the first rising portion 132A in the direction toward the second side 131b along the planting surface 1X.

The anode lead terminal 13 further includes a second rising portion 132B that rises in a direction intersecting with the flat surface portion 131 from a part of the other side (second side 131b) along the extending direction A of the flat surface portion 131. The second arm portion 133B extends from a part of the second rising portion 132B along the planting surface 1X to the first side 131a.

When viewed from the direction normal to the planting surface 1X, the first end portion 1331 of the first arm portion 133A and the second end portion 1332 of the second arm portion 133B face each other. However, a gap is formed between the first end portion 1331 and the second end portion 1332.

The size of the gap is not particularly limited. The length of the gap in the width direction B is the heights HHw and HLw from the flat surface portion 131 to the second portion 2b of the anode wire, and from the flat surface portion 131 to the farthest portion from the flat surface portion 131 of the arm portions 133A and 133B. It may be appropriately set according to the heights HH1 and HH2, the length D of the anode wire in the width direction B, and the like.

FIG. 2A is an enlarged perspective view showing a main part of the electrolytic capacitor according to the present embodiment. FIG. 2B is a plan view of the electrolytic capacitor of FIG. 2A viewed from the direction normal to the planting surface.

The anode lead terminal 13A includes a flat surface portion 131, two rising portions 132A and 132B, and two arm portions 133A and 133B. Each of the arm portions 133A and 133B has a flat plate shape, and one main surface of each is opposed to the planting surface 1X.

Each of the first arm portion 133A and the second arm portion 133B is a straight line when viewed in the normal direction of the flat surface portion 131. The angle formed between the straight line connecting the midpoint of the first end 1331 of the first arm portion 133A and the midpoint of the end on the first side side and the width direction B is 0 degree. The angle formed by the straight line connecting the midpoint of the second end portion 1332 of the second arm portion 133B and the midpoint of the end portion on the second side side and the width direction B is also 0 degrees.

Angle theta _2B that the angle theta _2A and flat portions 131 that forms flat portion 131 and a first rising portion 132A is that the second rising portion 132B are both 89 degrees. The first rising portion 132A and the angle theta _3A and the second rising portion 132B and the second angle theta _3B constituting the arm portion 133B and is formed by the first arm portion 133A are both 90 degrees.

The heights HH1 and HH2 from the flat surface portion 131 to the first end portion 1331 and the second end portion 1332 to the farthest point from the flat surface portion 131 are the same, and the heights HL1 and HH1 from the flat surface portion 131 to the closest point. The same applies to HL2. The height HH1 (HH2) is larger than the height HHw from the flat portion 131 of the second portion 2b of the anode wire to the farthest point. The height HL1 (HL2) is smaller than the height HLw from the flat surface portion 131 of the second portion 2b of the anode wire to the closest point. Further, the width Lg in the width direction B of the gap between the first end portion 1331 and the second end portion 1332 is the same as the diameter D in the width direction B of the second portion 2b of the anode wire.

Therefore, when viewed from the direction normal to the planting surface 1X, the entire end surface of the second portion 2b of the anode wire is arranged between the first end portion 1331 and the second end portion 1332. That is, in the present embodiment, the second portion 2b of the anode wire is supported by the anode lead terminal 13 by being sandwiched between both ends. The second portion 2b of the anode wire may be welded to the respective end faces of the first arm portion 133A and the second arm portion 133B.

FIG. 3A is a perspective view showing an enlarged main part of another electrolytic capacitor. In FIG. 3A, the exterior body is omitted for convenience. FIG. 3B is a plan view of the electrolytic capacitor of FIG. 3A viewed from the normal line direction of the planting surface.

The width Lg of the anode lead terminal 13B in the direction perpendicular to the extension direction A of the gap (width direction B) is smaller than the diameter D of the second portion 2b of the anode wire in the width direction B (Lg<D). The height HH1 (HH2) of the arm portion is smaller than the height HHw of the anode wire and slightly larger than the height HLw. Therefore, the second portion 2b of the anode wire is in contact with and supported by the edge of the first end portion 1331 of the first arm portion 133A and the edge of the second end portion 1332 of the second arm portion 133B.

The second portion 2b of the anode wire may be welded to the respective edges of the first arm portion 133A and the second arm portion 133B. Angle theta _2B that the angle theta _2A and flat portions 131 formed by the flat portion 131 and a first rising portion 132A and the second rising portion 132B are both 90 degrees. Except for these, the anode lead terminal 13B has the same configuration as the anode lead terminal 13A.

The shape of the anode lead terminal is not limited to this.
FIG. 4 is an enlarged perspective view showing a main part of an anode lead terminal according to another embodiment.
The anode lead terminal 13C has the same configuration as the anode lead terminal 13A, except that the end of the flat surface portion 131 that does not overlap with the capacitor element 10 forms the third rising portion 134. One main surface of the third rising portion 134 is exposed from the exterior body 11 together with a part of the flat surface portion 131. When the electrolytic capacitor and the substrate are connected by solder, the solder applied between the flat surface portion 131 and the substrate can wrap around to the third rising portion 134. Therefore, the adhesive strength between the electrolytic capacitor and the substrate is easily improved.

FIG. 5 is an enlarged perspective view showing a main part of an anode lead terminal according to still another embodiment.
In the anode lead terminal 13D, the first side 131a of the flat surface portion 131 is provided with two notches 131c along the width direction B. The first rising portion 132A is formed so as to include the band portion formed by the cut 131c. Similarly, the second side 131b is also provided with a notch, and the second rising portion 132B is formed so as to include the band portion formed by this notch. Other than these, the anode lead terminal 13D has the same configuration as the anode lead terminal 13A.

According to this, since a part of each rising portion can be formed using the flat surface portion 131, it is easy to adjust the size (height) of the rising portion. Further, since the rising portion can be formed so as to rise from the inside of the flat surface portion 131, the length of the flat surface portion 131 in the width direction B (the length in the width direction B from the first side 131a to the second side 131b) is increased. However, the rising portion is prevented from being exposed from the exterior body.

The electrolytic capacitor according to the present embodiment will be described in detail, taking a case where a solid electrolyte layer is provided as an electrolyte as an example.
FIG. 6 is a sectional view schematically showing an example of the electrolytic capacitor according to the present embodiment.

The electrolytic capacitor 20 has a capacitor element 10 having an anode part 6 and a cathode part 7, an outer package 11 that seals the capacitor element 10, an electrical connection with the anode part 6, and a part of the outer package 11. An exposed anode lead terminal 13 and a cathode lead terminal 14 electrically connected to the cathode portion 7 and partially exposed from the outer package 11 are provided.

The anode part 6 has an anode body 1 having a dielectric layer 3 and an anode wire 2. The cathode part 7 has a solid electrolyte layer 4 formed on the dielectric layer 3, and a cathode layer 5 (carbon layer 5a and metal paste layer 5b) that covers the surface of the solid electrolyte layer 4.

The first portion 2a including one end of the anode wire 2 is embedded in the anode body 1 from one surface (planting surface 1X) of the anode body 1. The second portion 2b including the other end of the anode wire 2 extends from the anode body 1, contacts the anode lead terminal 13, and is electrically connected. The second portion 2b of the anode wire and the anode lead terminal 13 may be welded. A part of anode lead terminal 13 (one main surface of flat surface portion 131) is exposed from one surface of exterior body 11.

The cathode layer 5 is electrically connected to the cathode lead terminal 14 via a conductive adhesive 8 (for example, a mixture of thermosetting resin and metal particles). One main surface of the cathode lead terminal 14 is also exposed from the same surface of the outer package 11. The exposed portions of the anode lead terminal 13 and the cathode lead terminal 14 are used for solder connection with a substrate (not shown) on which the electrolytic capacitor 20 is to be mounted and the like.

<Capacitor element>
(Anode part)
The anode part has an anode body and an anode wire extending from one surface of the anode body and electrically connected to the anode lead terminal.
The anode body is, for example, a rectangular parallelepiped porous sintered body obtained by sintering metal particles. As the metal particles, particles of valve action metal such as titanium (Ti), tantalum (Ta), niobium (Nb) are used. One type or two or more types of metal particles are used for the anode body. The metal particles may be an alloy composed of two or more kinds of metals. For example, an alloy containing a valve metal and silicon, vanadium, boron or the like can be used. Alternatively, a compound containing a valve metal and a typical element such as nitrogen may be used. The alloy of the valve action metal contains the valve action metal as a main component and contains, for example, 50 atom% or more of the valve action metal.

The anode wire is made of a conductive material. The material of the anode wire is not particularly limited, and examples thereof include copper, aluminum, and aluminum alloys in addition to the above valve action metal. The materials forming the anode body and the anode wire may be the same or different. The cross-sectional shape of the anode wire is not particularly limited, and examples thereof include a circle, a track shape (a shape including straight lines parallel to each other and two curves connecting the ends of these straight lines), an ellipse, a rectangle, and a polygon. .

The anode part is manufactured, for example, by pressure-molding a rectangular parallelepiped in a state where the first part is embedded in the powder of the metal particles, and sintering. As a result, the second portion of the anode wire is pulled out from one surface of the anode body so as to stand. The second portion is in contact with and electrically connected to the anode lead terminal. The second portion may be welded to the anode lead terminal. The welding method is not particularly limited, and examples thereof include resistance welding and laser welding.

A dielectric layer is formed on the surface of the anode body. The dielectric layer is made of, for example, a metal oxide. As a method of forming a layer containing a metal oxide on the surface of the anode body, for example, a method of anodizing the surface of the anode body by dipping the anode body in a chemical conversion solution, or the anode body under an atmosphere containing oxygen. The method of heating is mentioned. The dielectric layer is not limited to the layer containing the above metal oxide, and may have an insulating property.

(Cathode part)
The cathode part has a solid electrolyte layer formed on the dielectric layer and a cathode layer covering the solid electrolyte layer.
The solid electrolyte layer may be formed so as to cover at least a part of the dielectric layer. For the solid electrolyte layer, for example, a manganese compound or a conductive polymer is used. Examples of the conductive polymer include polypyrrole, polythiophene, polyfuran, polyaniline, polyacetylene, polyphenylene, polyparaphenylenevinylene, polyacene, polythiophenvinylene, polyfluorene, polyvinylcarbazole, polyvinylphenol, polypyridine, and derivatives of these polymers. Can be mentioned. These may be used alone or in combination of two or more. Further, the conductive polymer may be a copolymer of two or more kinds of monomers. It may be polythiophene, polyaniline, or polypyrrole in terms of excellent conductivity. In particular, polypyrrole may be used because it is excellent in water repellency.

The solid electrolyte layer containing the conductive polymer is formed, for example, by polymerizing a raw material monomer on the dielectric layer. Alternatively, it is formed by applying a liquid containing the conductive polymer to the dielectric layer. The solid electrolyte layer is composed of one or more solid electrolyte layers. When the solid electrolyte layer is composed of two or more layers, the composition and forming method (polymerization method) of the conductive polymer used in each layer may be different.

In the present specification, polypyrrole, polythiophene, polyfuran, polyaniline and the like mean polymers having a basic skeleton of polypyrrole, polythiophene, polyfuran, polyaniline and the like, respectively. Therefore, polypyrrole, polythiophene, polyfuran, polyaniline and the like may include their respective derivatives. For example, polythiophene includes poly(3,4-ethylenedioxythiophene) and the like.

Various dopants may be added to the polymerization liquid for forming the conductive polymer, the solution or the dispersion liquid of the conductive polymer in order to improve the conductivity of the conductive polymer. The dopant is not particularly limited, 1,5-naphthalenedisulfonic acid, 1,6-naphthalenedisulfonic acid, 1-octanesulfonic acid, 1-naphthalenesulfonic acid, 2-naphthalenesulfonic acid, 2,6-naphthalenedisulfonic acid, 2,7-naphthalenedisulfonic acid, 2-methyl-5-isopropylbenzenesulfonic acid, 4-octylbenzenesulfonic acid, 4-nitrotoluene-2-sulfonic acid, m-nitrobenzenesulfonic acid, n-octylsulfonic acid, n-butane Sulfonic acid, n-hexanesulfonic acid, o-nitrobenzenesulfonic acid, p-ethylbenzenesulfonic acid, trifluoromethanesulfonic acid, hydroxybenzenesulfonic acid, butylnaphthalenesulfonic acid, benzenesulfonic acid, polystyrenesulfonic acid, polyvinylsulfonic acid, methane Examples thereof include sulfonic acid and derivatives thereof. Examples of the derivative include metal salts such as lithium salt, potassium salt and sodium salt, ammonium salts such as methylammonium salt, dimethylammonium salt and trimethylammonium salt, piperidinium salt, pyrrolidinium salt and pyrrolinium salt.

When the conductive polymer is dispersed in the dispersion medium in the form of particles, the average particle diameter D50 of the particles is, for example, 0.01 μm or more and 0.5 μm or less. When the average particle diameter D50 of the particles is within this range, the particles easily penetrate into the inside of the anode body.

The cathode layer has, for example, a carbon layer formed so as to cover the solid electrolyte layer, and a metal paste layer formed on the surface of the carbon layer. The carbon layer contains a conductive carbon material such as graphite and a resin. The metal paste layer contains, for example, metal particles (for example, silver) and a resin. The configuration of the cathode layer is not limited to this configuration. The cathode layer may have any structure as long as it has a current collecting function.

<Anode lead terminal>
An anode wire is joined to the arm portion of the anode lead terminal by a conductive adhesive, solder, resistance welding or laser welding. One main surface of the flat surface portion of the anode lead terminal is exposed from the exterior body.

The material of the anode lead terminal is not particularly limited as long as it is electrochemically and chemically stable and has conductivity. The anode lead terminal may be a metal such as copper or a nonmetal. The shape is not particularly limited, and is, for example, a flat plate shape. The thickness of the anode lead terminal (the length between the main surfaces of the anode lead terminal) may be 25 μm or more and 200 μm or less, or 25 μm or more and 100 μm or less from the viewpoint of reducing the height.

<Cathode lead terminal>
The cathode lead terminal is bonded to the cathode layer via, for example, a conductive adhesive material. One main surface of the cathode lead terminal is arranged inside the exterior body. The other main surface of the cathode lead terminal is exposed from the exterior body.

The material of the cathode lead terminal is not particularly limited as long as it is electrochemically and chemically stable and has conductivity. The cathode lead terminal may be a metal such as copper or a nonmetal. The shape is not particularly limited, and is, for example, a flat plate shape. The thickness of the cathode lead terminal may be 25 μm or more and 200 μm or less, or 25 μm or more and 100 μm or less, from the viewpoint of reducing the height.

<Exterior body>
The outer package is provided to electrically insulate the anode lead terminal and the cathode lead terminal, and is made of an insulating material (exterior body material). The exterior body material includes, for example, a thermosetting resin. Examples of the thermosetting resin include epoxy resin, phenol resin, silicone resin, melamine resin, urea resin, alkyd resin, polyurethane, polyimide and unsaturated polyester.

<Method of manufacturing electrolytic capacitor>
The electrolytic capacitor includes, for example, a step of preparing a capacitor element (S1), a step of preparing an anode lead terminal and a cathode lead terminal (S2), a joining step of joining each lead terminal to a capacitor element (S3), and a capacitor. It is manufactured by a method including a sealing step (S4) of sealing the element, a part of the anode lead terminal and a part of the cathode lead terminal. FIG. 7 is a flowchart showing the method for manufacturing the electrolytic capacitor according to the present embodiment.

The method for manufacturing the electrolytic capacitor according to the present embodiment will be described in detail by taking as an example the case where the second portion of the anode wire is sandwiched between the two arm portions of the anode lead terminal.

(1) Capacitor Element Preparation Step The valve action metal particles and the anode wire are put into a mold so that the first portion is embedded in the valve action metal particles, pressure-molded, and then sintered in a vacuum, An anode part, a part of which is embedded in the porous sintered body from one surface, is prepared. The pressure at the time of pressure molding is not particularly limited and is, for example, about 10 N or more and 100 N or less. The valve action metal particles may be mixed with a binder such as polyacrylic carbonate, if necessary.

Next, a dielectric layer is formed on the anode body. Specifically, the anode body is immersed in a chemical conversion tank filled with an electrolytic aqueous solution (for example, phosphoric acid aqueous solution), and the second portion of the anode wire is connected to the anode body of the chemical conversion tank to perform anodization. Thus, the dielectric layer made of the oxide film of the valve metal can be formed on the surface of the anode body. The electrolytic aqueous solution is not limited to the phosphoric acid aqueous solution, and nitric acid, acetic acid, sulfuric acid or the like can be used.

Then, a solid electrolyte layer is formed. In this embodiment, a process of forming a solid electrolyte layer containing a conductive polymer will be described.
The solid electrolyte layer containing a conductive polymer is, for example, a method of impregnating an anode body on which a dielectric layer is formed with a monomer or oligomer, and then polymerizing the monomer or oligomer by chemical polymerization or electrolytic polymerization, or The anode body on which the body layer is formed is impregnated with a solution or dispersion of a conductive polymer and dried to form at least a part of the dielectric layer.

A carbon paste and a metal paste are sequentially applied to the surface of the solid electrolyte layer to form a cathode layer composed of the carbon layer and the metal paste layer. The structure of the cathode layer is not limited to this, and may be any structure having a current collecting function.
The capacitor element is manufactured by the above method.

(2) Preparation Steps for Anode Lead Terminal and Cathode Lead Terminal The anode lead terminal is formed by, for example, punching a single plate-shaped conductor (conductor plate) into a predetermined shape and then bending the conductor a plurality of times. It can be manufactured by a simple method.

When the anode lead terminal of this embodiment is expanded, the portions corresponding to the respective arm portions are arranged along the extending direction A. Therefore, the length in the width direction B required to manufacture one anode lead terminal does not have to include the length of the arm portion. Therefore, a plurality of anode lead terminals can be efficiently manufactured from a single conductor plate.

FIG. 8A is a plan view showing a conductor plate which is a material of the anode lead terminal and a planned punching line. FIG. 8B is a perspective view schematically showing a precursor of an anode lead terminal in which a rising portion is formed. FIG. 8C is a perspective view schematically showing the precursor of the anode lead terminal in which the arm portion is formed.

The conductor plate 60 is punched, for example, according to the punching line P13. When the stamped precursor of the anode lead terminal is bent along the first planned bending line L1A, the first rising portion 132A is formed, and when it is bent along the second planned bending line L1B, the second rising portion is formed. 132B is formed. Subsequently, the precursor of the anode lead terminal is bent along the third planned bending line L2A and is also bent along the fourth planned bending line L2B to form each arm portion.

Similarly, the cathode lead terminal may be formed by punching a conductor plate into a predetermined shape. The anode lead terminal and the cathode lead terminal may be manufactured by punching out the same single conductor plate.

(3) Joining Step The anode lead terminal and the cathode lead terminal are arranged at predetermined positions. At this time, a conductive adhesive is applied to a predetermined position on the cathode layer.

The capacitor element is mounted on the anode lead terminal and the cathode lead terminal arranged at predetermined positions. A part of the capacitor element may be overlapped with the flat surface portion of the anode lead terminal. The second portion of the anode wire is disposed above the flat surface portion of the anode lead terminal, and at least a portion of the second portion is located between the first end portion of the first arm portion and the second end portion of the second arm portion. To intervene. The second part need not yet be in contact with any of the arms.

Then, for example, each rising portion is pressed toward the second portion, and the inclination of each rising portion is changed so as to narrow the gap between the two arm portions. As a result, the end of each arm and the second portion are brought into contact with each other. According to this method, the anode wire can be fixed without applying a load to the anode wire in the direction of the normal to the flat surface.

FIG. 8D is a perspective view showing a state where the anode wire is sandwiched between two arm portions.
The entire end surface of the second portion 2b is interposed between the first end portion of the first arm portion 133A and the second end portion of the second arm portion 133B, but the second portion 2b is still in any arm. There is no contact with the section. Subsequently, the first rising portion 132A and the second rising portion 132B are pressed toward the second portion 2b, so that the ends of the two arm portions come into contact with the second portion 2b.

Next, the second portion of the anode wire and the vicinity of the end of the arm portion of the anode lead terminal are joined by laser welding, resistance welding, or the like. As a result, a capacitor element in which the lead terminals are joined is obtained.

(4) Sealing Step The material of the capacitor element and the outer casing (for example, uncured thermosetting resin and filler) is placed in a mold, and the capacitor element is sealed by a transfer molding method, a compression molding method, or the like. At this time, a part of the anode lead terminal and the cathode lead terminal is exposed from the mold. The molding conditions are not particularly limited, and the time and temperature conditions may be appropriately set in consideration of the curing temperature of the thermosetting resin used.

After the mold is heated to cure the material of the outer package, the capacitor element covered with the outer package is taken out of the mold. As a result, an electrolytic capacitor including a capacitor element, an anode lead terminal, a cathode lead terminal, and an exterior body that covers a part of the capacitor element and each lead terminal can be obtained.

INDUSTRIAL APPLICABILITY The electrolytic capacitor according to the present invention has high connection reliability between the anode wire and the anode lead terminal, and thus can be used for various purposes.

20: Electrolytic capacitor 10: Capacitor element 1: Anode body 1X: Planting surface 2: Anode wire 2a: First portion 2b: Second portion 3: Dielectric layer 4: Solid electrolyte layer 5: Cathode layer 5a: Carbon layer 5b: Metal paste layer 6: Anode part 7: Cathode part 8: Conductive adhesive 11: Outer package 13, 13A, 13B, 13C, 13D: Anode lead terminal 131: Flat part 131a: First side 131b: Second side 131c: Notch 132A: First rising portion 132B: Second rising portion 133A: First arm portion 1331: First end portion 133B: Second arm portion 1332: Second end portion 134: Third rising portion P13: Scheduled punching line L1A: First planned bending line L1B: Second planned bending line L2A: Third planned bending line
L2B: 4th planned bending line 14: Cathode lead terminal 60: Conductor plate

Claims (5)

A capacitor element having an anode part and a cathode part;
An anode lead terminal electrically connected to the anode part,
A cathode lead terminal electrically connected to the cathode part,
An exterior body covering the capacitor element,
The anode part has an anode body and an anode wire extending from a planting surface of the anode body,
The anode lead terminal is
A flat portion existing along the extending direction of the anode wire,
From at least a part of one first side along the extending direction of the flat surface portion, a first rising portion rising in a direction intersecting with the flat surface portion,
A second rising portion rising from at least a part of the other second side along the extending direction of the flat surface portion in a direction intersecting with the flat surface portion;
A first arm portion extending from at least a part of the first rising portion in a direction toward the second side;
A second arm portion extending from at least a part of the second rising portion in a direction toward the first side,
When viewed from the normal direction of the planting surface, the first end portion of the first arm portion on the second side side and the second end portion of the second arm portion on the first side side, It is arranged so as to face each other,
An electrolytic capacitor, wherein the anode wire is in contact with the first end and the second end. The electrolytic capacitor according to claim 1, wherein the anode wire is sandwiched between the first end portion and the second end portion. The electrolytic capacitor according to claim 1, wherein the anode wire is supported by the edge of the first end and the edge of the second end. The said 1st arm part and the said 2nd arm part are all flat-plate-shaped, and the one main surface of each is facing the said planting surface, The any one of Claims 1-3. Electrolytic capacitor. The electrolytic capacitor according to claim 1, wherein the anode wire is welded to the first end and the second end.

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