JP7382591B2 - Electrolytic capacitor and its manufacturing method - Google Patents

Description

The present invention relates to an electrolytic capacitor and a method for manufacturing the same.

Electrolytic capacitors have low equivalent series resistance (ESR) and excellent frequency characteristics, so they are installed in various electronic devices. Electrolytic capacitors typically include a capacitor element that includes an anode portion and a cathode portion. The anode portion includes a porous anode body, and a dielectric layer is formed on the surface of the anode body. The dielectric layer is in contact with the electrolyte. There are electrolytic capacitors that use solid electrolytes such as conductive polymers as electrolytes.

Patent Document 1 discloses that an insulating protective layer is formed around the root of the anode lead wire protruding from the anode body, and an insulating protective layer is formed around the capacitor element including the cathode terminal connected to the cathode part and the protective layer. An electrolytic capacitor having a release layer formed thereon is disclosed.

Japanese Patent Application Publication No. 2009-182157

Improving the reliability of electrolytic capacitors using solid electrolytes.

One aspect of the present disclosure provides a capacitor element including 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 including an anode part and a cathode part. a first adhesive material that is interposed between the cathode lead terminal and has conductivity; and an exterior body that covers the capacitor element with parts of the anode lead terminal and the cathode lead terminal exposed; The present invention relates to an electrolytic capacitor, wherein at least a portion of a gap between the cathode portion and the cathode lead terminal, where the first adhesive is not present, is filled with a second adhesive.

Other aspects of the present disclosure include a step of preparing a capacitor element including an anode portion and a cathode portion, a step of preparing an anode lead terminal and a cathode lead terminal, and an electrical connection between the anode portion and the anode lead terminal. and forming an electrical connection between the cathode portion and the cathode lead terminal, and sealing the capacitor element with an exterior body, the step of forming an electrical connection between the cathode portion and the cathode lead terminal. The electrical connection is made by interposing a conductive first adhesive between the cathode part and the cathode lead terminal, and the cathode part and the cathode lead without the first adhesive interposed therebetween. The present invention relates to a method of manufacturing an electrolytic capacitor, further comprising the step of filling at least a portion of the gap between the terminals with a second adhesive.

Improves reliability of electrolytic capacitors.

FIG. 2 is a perspective view showing a connection between a cathode portion and a cathode lead terminal in an electrolytic capacitor according to an embodiment of the present invention. FIG. 2 is a cross-sectional view showing a connection between a cathode portion and a cathode lead terminal in an electrolytic capacitor according to an embodiment of the present invention. FIG. 7 is a perspective view showing another example of connection between a cathode portion and a cathode lead terminal in an electrolytic capacitor according to an embodiment of the present invention. FIG. 7 is a cross-sectional view showing another example of the connection between the cathode portion and the cathode lead terminal in the electrolytic capacitor according to the embodiment of the present invention. 1 is a cross-sectional view schematically showing an electrolytic capacitor according to an embodiment of the present invention.

[Electrolytic capacitor]
An electrolytic capacitor according to an embodiment of the present invention includes a capacitor element including an anode part and a cathode part, an anode lead terminal electrically connected to the anode part, and a cathode lead terminal electrically connected to the cathode part. a first conductive adhesive interposed between the cathode part and the cathode lead terminal; and an exterior body covering the capacitor element with parts of the anode lead terminal and the cathode lead terminal exposed; Equipped with

A conductive paste such as silver paste is usually used as the first adhesive. The first adhesive can be applied onto the cathode part or the cathode lead terminal with a nozzle using, for example, a dispenser or the like. In this case, the first adhesive is not applied so as to cover the entire area where the cathode part and the cathode lead terminal are overlapped, but is applied to a part of the area where the cathode part and the cathode lead terminal are overlapped. There may be areas where one adhesive is not present. That is, there may be a gap between the cathode portion and the cathode lead terminal in which the first adhesive is not present. It is difficult to completely fill this gap with the exterior body, and a gap may exist between the cathode portion and the cathode lead terminal. As a result, the adhesive strength between the cathode portion and the cathode lead terminal is likely to decrease due to thermal stress or external impact.

In the electrolytic capacitor of this embodiment, at least a portion of the gap between the cathode portion and the cathode lead terminal where the first adhesive is not present is filled with the second adhesive. The second adhesive material can strengthen the adhesion between the cathode part and the cathode lead terminal. This prevents the bond between the cathode portion and the cathode lead terminal from peeling off due to thermal stress or external impact. Therefore, reliability of the electrolytic capacitor can be improved.

The surface of the cathode portion may have a first main surface and a second main surface that intersects and adjoins the first main surface. The anode body usually has a rectangular parallelepiped shape. In that case, the cathode portion may also be formed along the surface of the rectangular parallelepiped of the anode body. When the first main surface of the cathode section contacts the first adhesive, the second main surface of the cathode section is a surface that is substantially orthogonal to the first main surface.

The cathode lead terminal may extend along the first main surface and then be bent so as to extend along the second main surface. In this case, the second adhesive may fill at least a portion of the gap between the cathode lead terminal and the second main surface. In this case, the adhesiveness between the cathode part and the cathode lead terminal becomes stronger, and peeling of the adhesive part between the cathode part and the cathode lead terminal is more significantly suppressed.

The second adhesive is preferably one that easily enters the gap between the cathode portion and the cathode lead terminal. In this regard, even if the second adhesive does not contain a filler or contains a filler (second filler), the average particle size of the filler can be the same as that of the first adhesive. It may be smaller than the average particle diameter of the conductive filler (first filler). In addition, when using a conductive paste as the first adhesive, the conductive particles contained in the conductive paste correspond to the first filler, and the average particle diameter of the conductive particles is the average particle diameter of the first filler. can be equivalent to

When the first adhesive includes a first filler, the average particle diameter D1 of the first filler may be 0.1 μm or more, or 1 μm or more. The average particle diameter D1 may be 100 μm or less, or 20 μm or less. The average particle diameter D1 may be 0.1 μm or more and 100 μm or less.

On the other hand, when the second adhesive material includes a second filler, the average particle diameter D2 of the second filler may be 10 nm or more, and may be 50 nm or more. The average particle diameter D2 may be 10 μm or less, 5 μm or less, or 1 μm or less. The average particle diameter D2 may be, for example, 10 nm or more and 10 μm or less.

The ratio D2/D1 of the average particle diameter D2 of the second filler to the average particle diameter D1 of the first filler may be less than 1. D2/D1 may be 0.5 or less, or may be 0.1 or less. D2/D1 may be 0.0005 or more, or may be 0.001 or more.

The exterior body may include an insulating filler (third filler). In this case, the average particle diameter of the third filler may be larger than the distance between the cathode part and the cathode lead terminal. In this case, the third filler is difficult to enter the gap between the cathode part and the cathode lead terminal. Therefore, it is difficult to fill the gap between the cathode portion and the cathode lead terminal with the exterior body, and the adhesive strength tends to decrease. However, by using the second adhesive, even when using an exterior body containing a third filler with a large average particle size, a decrease in adhesive strength and peeling of the adhesive between the cathode part and the cathode lead terminal can be prevented. can. Note that the distance between the cathode part and the cathode lead terminal means an average at a plurality of positions (for example, 10 or more positions).

Note that the average particle diameter of the first adhesive material, the second adhesive material, and each filler that may be included in the exterior body is determined by image analysis of a cross-sectional photograph of a predetermined region of the electrolytic capacitor. In an enlarged photograph of a cross section obtained by a scanning electron microscope (SEM) or a transmission electron microscope (TEM), a circle (hereinafter referred to as "equivalent circle") with an area equal to the area within the closed curve formed by the outline of the filler Determine the diameter and use it as the particle size of the filler. Equivalent yen is calculated for a plurality of fillers (for example, 10 or more). Let the average value of the equivalent circle be the average particle diameter of the filler. If the filler is metal particles and the metal particles are recognized to be integrated by agglomeration, fusion, or sintering, divide the total area of the multiple agglomerated, fused, or sintered metal particles by the number of metal particles. The particle diameters of these fillers may be calculated by regarding this value as the area of one metal particle.

Hereinafter, the configuration of the electrolytic capacitor according to this embodiment will be described with reference to the drawings as appropriate. However, the present invention is not limited thereto.

FIGS. 1A and 1B are schematic diagrams in which a capacitor element and a cathode lead terminal are extracted and displayed in the electrolytic capacitor of this embodiment, and show how the cathode portion and the cathode lead terminal are connected. FIG. 1A is a perspective view, and FIG. 1B is a cross-sectional view seen from the lateral direction (width direction of the cathode lead terminal).

In FIGS. 1A and 1B, the cathode portion of the capacitor element 10 has a plurality of main surfaces, and the cathode portion 7 and the cathode lead terminal 14 on the lower main surface (first main surface) S1. It is bonded with. The cathode portion 7 and the cathode lead terminal 14 are connected via a conductive first adhesive 8. However, the first adhesive 8 is not formed on the entire surface of the first main surface S1, which is the surface of the cathode portion 7, in the region facing the cathode lead terminal 14. A second adhesive 9 is formed in a part of the area where the first adhesive 8 is not formed, which is in the area of the first main surface S1 facing the cathode lead terminal 14. The second adhesive 9 is formed to surround the first adhesive 8.

The cathode lead terminal 14 extends along the first main surface S1 of the cathode section 7, then bends and extends upright from the first main surface S1, and further extends away from the first main surface S1. It is bent from the position and extends in a direction parallel to the first main surface S1 and away from the capacitor element 10. A portion of the cathode lead terminal 14 extending bent from a position away from the first main surface S1 may be connected to an external terminal.

An anode wire 2 protrudes from the capacitor element 10. The anode wire 2 may be connected to an anode lead terminal (not shown).

2A and 2B are schematic diagrams showing other examples of the connection between the cathode part and the cathode lead terminal in the electrolytic capacitor of this embodiment. Similar to FIGS. 1A and 1B, the capacitor element and the cathode lead terminal are extracted and shown. FIG. 2A is a perspective view, and FIG. 2B is a sectional view viewed from the lateral direction (width direction of the cathode lead terminal).

In FIGS. 2A and 2B, the cathode portion 7 of the capacitor element 10 has a plurality of main surfaces, and the cathode portion 7 and the cathode lead terminal 14 on the upper main surface (first main surface) S1. It is bonded with. The cathode portion 7 and the cathode lead terminal 14 are connected via a conductive first adhesive 8. A region of the first main surface S1 of the cathode portion 7 facing the cathode lead terminal 14 has a region where the first adhesive 8 is not formed. A second adhesive 9 is formed in a part of the area where the first adhesive 8 is not formed, which is in the area of the first main surface S1 facing the cathode lead terminal 14.

The cathode lead terminal 14 extends along the first main surface S1 of the cathode section 7, and then bends and extends along the second main surface S2. A second adhesive 9 is interposed between the cathode lead terminal 14 and the second main surface S2. After extending along the second main surface S2, the cathode lead terminal 14 is further bent and extends parallel to the first main surface S1 and upright from the second main surface S2. A portion of the cathode lead terminal 14 extending vertically from the second main surface S2 is exposed from the exterior body and is connected to an external terminal.

FIG. 3 is a schematic cross-sectional view of the electrolytic capacitor 20 according to this embodiment. In FIG. 3, the cathode portion 7 and the cathode lead terminal 14 are arranged and electrically connected in the configuration shown in FIGS. 2A and 2B.

The electrolytic capacitor 20 includes a capacitor element 10 having an anode part 6 and a cathode part 7 , an exterior body 11 that seals the capacitor element 10 , and an electrically connected to the anode part 6 , with a part of the exterior body 11 being electrically connected to the anode part 6 . It includes an exposed anode lead terminal 13 and a cathode lead terminal 14 electrically connected to the cathode section 7 and partially exposed from the exterior body 11. The anode section 6 includes an anode body 1 and an anode wire 2. A dielectric layer 3 is formed on the surface of the anode body. The cathode section 7 includes a solid electrolyte layer 4 that covers at least a portion of the dielectric layer 3 and a cathode layer 5 that covers the surface of the solid electrolyte layer 4.

<Capacitor element>
Hereinafter, the capacitor element 10 will be described in detail, taking as an example a case where the capacitor element 10 is provided with a solid electrolyte layer as an electrolyte.

The anode section 6 includes an anode body 1 and an anode wire 2 extending from one surface of the anode body 1 and electrically connected to an anode lead terminal 13 .
The anode body 1 is, for example, a rectangular parallelepiped porous sintered body obtained by sintering metal particles. As the metal particles, particles of valve metal such as titanium (Ti), tantalum (Ta), and niobium (Nb) are used. The anode body 1 uses one or more types of metal particles. The metal particles may be an alloy of two or more metals. For example, an alloy containing a valve metal and silicon, vanadium, boron, etc. can be used. Further, a compound containing a valve metal and a typical element such as nitrogen may be used. The valve metal alloy has a valve metal as a main component, and contains, for example, 50 atomic percent or more of the valve metal.

The anode wire 2 is made of a conductive material. The material of the anode wire 2 is not particularly limited. The materials constituting the anode body 1 and the anode wire 2 may be the same or different. The anode wire 2 has a first portion 2 a buried inside the anode body 1 from one surface of the anode body 1 and a second portion 2 b extending from the one surface of the anode body 1 .

The anode portion 6 is produced, for example, by embedding the first portion 2a in the metal particle powder, press-molding it into a rectangular parallelepiped shape, and sintering it. Thereby, the second portion 2b of the anode wire 2 is pulled out from one surface of the anode body 1 so as to stand up. The second portion 2b is joined to the anode lead terminal 13 by welding or the like, so that the anode wire 2 and the anode lead terminal 13 are electrically connected. The welding method is not particularly limited, and examples thereof include resistance welding, laser welding, and the like.

A dielectric layer 3 is formed on the surface of the anode body 1 . The dielectric layer 3 is made of, for example, a metal oxide. Examples of methods for forming a layer containing a metal oxide on the surface of the anode body 1 include a method in which the surface of the anode body 1 is anodized by immersing the anode body 1 in a chemical solution; Examples include a method of heating in an atmosphere containing The dielectric layer 3 is not limited to a layer containing the above-mentioned metal oxide, as long as it has insulating properties.

(Cathode part)
The cathode section 7 includes a solid electrolyte layer 4 and a cathode layer 5 covering the solid electrolyte layer 4 . Solid electrolyte layer 4 is formed to cover at least a portion of dielectric layer 3 .

For example, a manganese compound or a conductive polymer is used for the solid electrolyte layer 4. Examples of the conductive polymer include polypyrrole, polythiophene, polyfuran, polyaniline, and derivatives of these polymers. These may be used alone or in combination. Further, the conductive polymer may be a copolymer of two or more types of monomers. Polythiophene, polyaniline, and polypyrrole may be used since they have excellent conductivity. In particular, polypyrrole may be used since it has excellent water repellency.

The solid electrolyte layer 4 containing the conductive polymer is formed, for example, by polymerizing raw material monomers on the dielectric layer 3. Alternatively, it is formed by applying a liquid containing the conductive polymer to the dielectric layer 3. The solid electrolyte layer 4 is composed of one or more solid electrolyte layers. When the solid electrolyte layer 4 is composed of two or more layers, the composition, formation method (polymerization method), etc. of the conductive polymer used in each layer may be different.

Various dopants may be added to the polymerization solution, solution or dispersion of the conductive polymer for forming the conductive polymer in order to improve the conductivity of the conductive polymer. Examples of the dopant include, but are not limited to, naphthalenesulfonic acid, p-toluenesulfonic acid, polystyrenesulfonic acid, and the like.

The cathode layer 5 includes, for example, a carbon layer 5a formed to cover the solid electrolyte layer 4, and a metal paste layer 5b formed on the surface of the carbon layer 5a. The carbon layer 5a contains a conductive carbon material such as graphite and resin. The metal paste layer 5b includes, for example, metal particles (eg, silver) and resin. Note that the configuration of the cathode layer 5 is not limited to this configuration. The structure of the cathode layer 5 may be any structure as long as it has a current collecting function.

<Anode lead terminal>
The anode lead terminal 13 is electrically connected to the anode body 1 via the second portion 2b of the anode wire 2. The material of the anode lead terminal 13 is not particularly limited as long as it is electrochemically and chemically stable and has conductivity. The anode lead terminal 13 may be made of metal such as copper, or may be made of non-metal. Its shape is not particularly limited as long as it is flat. The thickness of the anode lead terminal 13 (the distance between the main surfaces of the anode lead terminal 13) 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.

One end of the anode lead terminal 13 may be joined to the anode wire 2 with a conductive adhesive or solder, or may be joined to the anode wire 2 by resistance welding or laser welding. The other end of the anode lead terminal 13 is led out of the exterior body 11 and exposed from the exterior body 11 . The conductive adhesive is, for example, a mixture of a thermosetting resin and carbon particles or metal particles, which will be described later.

<Cathode lead terminal>
The cathode lead terminal 14 is electrically connected to the cathode layer 5 (cathode portion 7) at the joint portion 14a. The joint portion 14a is a portion of the cathode lead terminal 14 that overlaps the cathode layer 5 when the cathode layer 5 and the cathode lead terminal 14 joined to the cathode layer 5 are viewed from the normal direction of the cathode layer 5.

Cathode lead terminal 14 is bonded to cathode layer 5 via conductive first adhesive 8 . One end of the cathode lead terminal 14 constitutes, for example, a part of the joint portion 14a, and is arranged inside the exterior body 11. The other end of the cathode lead terminal 14 is led out. Therefore, a portion of the cathode lead terminal 14 including the other end is exposed from the exterior body 11.

A first adhesive 8 is formed between the cathode layer 5 and the cathode lead terminal 14 in a part of the joint portion 14a. A second adhesive 9 is formed between the cathode layer 5 and the cathode lead terminal 14 in at least a portion of the remaining portion of the joint portion 14a.

The cathode lead terminal 14 extends along the first main surface S1 of the cathode layer 5, and is then bent substantially perpendicularly along the second main surface S2 adjacent to the first main surface S1. The cathode lead terminal 14 is further bent so as to stand upright from the second main surface S2, and is led out to the outside where it is exposed from the exterior body 11. A second adhesive 9 is also interposed between the second main surface S2 and the cathode layer 5. The portion of the cathode lead terminal 14 exposed from the exterior body 11 is further bent along the exterior body 11.

The material of the cathode lead terminal 14 is also not particularly limited as long as it is electrochemically and chemically stable and has conductivity. The cathode lead terminal 14 may be made of metal such as copper, or may be made of a non-metal. The shape is also not particularly limited, and may be elongated and flat, for example. The thickness of the cathode lead terminal 14 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.

<First and second adhesive>
The first adhesive 8 is made of, for example, a conductive paste. The conductive paste may include conductive particles, a binder resin, a dispersion medium, additives, and the like. Examples of the dispersion medium include water, organic media, and mixtures thereof. The first adhesive 8 can be formed by removing the dispersion medium by drying and curing the binder resin. As the conductive particles, metal particles, conductive carbon particles, etc. can be used. The metal particles may include, for example, silver, copper, nickel, or the like.

The second adhesive 9 is, for example, a dispersion containing a binder resin and a dispersion medium, in the gap between the first main surface S1 on which the first adhesive 8 is not formed and the cathode lead terminal 14; It can be formed by infiltrating the gap between the second main surface S2 and the cathode lead terminal 14 using capillary action, removing the dispersion medium by drying, and curing the binder resin. The dispersion preferably has a suitably low viscosity before curing, since the second adhesive can be easily formed even in a small gap. In this respect, the dispersion preferably does not contain a filler, or even if it contains a filler, the average particle size of the filler is preferably small.

The first adhesive 8 may contain a filler (first filler). Note that when the first adhesive 8 is formed from a conductive paste, conductive particles contained in the paste may correspond to the first filler. When the second adhesive 9 includes a filler (second filler), the average particle diameter D2 of the second filler is smaller than the average particle diameter D1 of the first filler contained in the first adhesive 8. It's good to do that. Examples of the second filler include silica particles, alumina particles, carbon particles, and the like. Metal particles such as silver, copper, and nickel may also be used. The second filler is used when filling the gap between the first main surface S1 and/or the second main surface S2 and the cathode lead terminal 14 with the second adhesive 9. An insulating material is preferable because it does not cause problems such as short circuits due to the second adhesive 9 adhering to the vicinity of the boundary.

In the first adhesive material 8 and the second adhesive material 9, the binder resin is not particularly limited, and any known binder resin can be used. Examples of the binder resin include thermoplastic resins (polyester resins, etc.), thermosetting resins (polyimide resins, epoxy resins, etc.), and the like.

<Exterior body>
The exterior body 11 is provided to electrically insulate the anode lead terminal 13 and the cathode lead terminal 14, 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.

≪Manufacturing method of electrolytic capacitor≫
The method for manufacturing an electrolytic capacitor according to the present embodiment includes a step of preparing a capacitor element having an anode part and a cathode part, a step of preparing an anode lead terminal and a cathode lead terminal, and an electrical connection between the anode part and the anode lead terminal. The method includes the steps of forming a connection and forming an electrical connection between the cathode portion and the cathode lead terminal, and sealing the capacitor element with an exterior body. Here, the electrical connection between the cathode part and the cathode lead terminal is performed by interposing a conductive first adhesive between the cathode part and the cathode lead terminal. The manufacturing method further includes the step of filling at least a portion of the gap between the cathode part and the cathode lead terminal, where the first adhesive is not interposed, with the second adhesive.

An example of the method for manufacturing an electrolytic capacitor according to this embodiment will be described below, taking as an example the manufacturing of the electrolytic capacitor 20 shown in FIG.

(1) Preparation process First, the capacitor element 10 is prepared.
The valve metal particles and the anode wire 2 are placed in a mold so that the first portion 2a is embedded in the valve metal particles, pressure-molded, and then sintered to produce an anode body that is a porous body of the valve metal. 1 is obtained. The first portion 2a of the anode wire is embedded in the porous sintered body from one side thereof. The pressure during pressure molding is not particularly limited. Sintering is preferably performed under reduced pressure. If necessary, a binder such as polyacrylic carbonate may be mixed with the valve metal particles.

Next, the anode body 1 is subjected to a chemical conversion treatment, and at least a portion of the anode body 1 is covered with a dielectric layer 3. Specifically, the anode body 1 is immersed in a chemical conversion bath filled with an electrolytic aqueous solution (for example, a phosphoric acid aqueous solution), the second portion 2b of the anode wire 2 is connected to the anode body of the chemical conversion bath, and the anodization is performed. By doing this, a dielectric layer 3 made of an oxide film of a valve metal can be formed on the surface of the porous portion. The electrolytic aqueous solution is not limited to a phosphoric acid aqueous solution, and nitric acid, acetic acid, sulfuric acid, etc. can be used.

Subsequently, at least a portion of the dielectric layer 3 is covered with a solid electrolyte layer 4. Thereby, a capacitor element 10 is obtained that includes the anode body 1, the dielectric layer 3 covering at least a portion of the anode body, and the solid electrolyte layer 4 covering at least a portion of the dielectric layer.
The solid electrolyte layer 4 containing a conductive polymer can be prepared, for example, by impregnating the anode body 1 on which the dielectric layer 3 is formed with monomers or oligomers, and then polymerizing the monomers or oligomers by chemical polymerization or electrolytic polymerization. Alternatively, at least a portion of the dielectric layer 3 is formed by impregnating the anode body 1 on which the dielectric layer 3 is formed with a solution or dispersion of a conductive polymer and drying it.

Finally, by sequentially applying carbon paste and metal paste to the surface of solid electrolyte layer 4, cathode layer 5 composed of carbon layer 5a and metal paste layer 5b is formed. The structure of the cathode layer 5 is not limited to this, and may be any structure as long as it has a current collecting function.
By the above method, a capacitor element including an anode section 6 and a cathode section 7 is obtained.

(2) Lead terminal bonding step Next, the anode lead terminal 13 and the cathode lead terminal 14 are prepared. The cathode lead terminal 14 is bent in advance into a crank shape so that it is arranged along the first main surface S1 and the second main surface S2 of the cathode section. The second portion 2b of the anode wire 2 planted from the anode body 1 is joined to the anode lead terminal 13 by laser welding, resistance welding, or the like. Further, after applying the first adhesive 8 to the first main surface S1 of the cathode layer 5, the cathode lead terminal 14 is joined to the cathode portion 7 via the first adhesive 8. Thereby, the anode part 6 is electrically connected to the anode lead terminal 13, and the cathode part 7 is electrically connected to the cathode lead terminal 14.

Thereafter, a fluidized second adhesive 9 is applied to the gap between the cathode lead terminal 14 and the first main surface and the gap between the cathode lead terminal 14 and the second main surface. Pour into the gap. The second adhesive 9 can penetrate into the gap by capillary action. Thereafter, the second adhesive 9 is cured, and at least a portion of each gap is filled with the second adhesive 9.

(3) Sealing process Subsequently, the materials for the capacitor element 10 and the exterior body 11 (e.g., a resin composition containing an uncured thermosetting resin and a filler) are placed in a mold, and transferred molding, compression molding, etc. The capacitor element 10 is sealed by, etc. The molding conditions are not particularly limited, and the time and temperature conditions may be set as appropriate, taking into consideration the curing temperature of the thermosetting resin used. At this time, a portion of the anode lead terminal 13 and the cathode lead terminal 14 are exposed from the mold. The molding conditions are not particularly limited, and the time and temperature conditions may be set as appropriate, taking into consideration the curing temperature of the thermosetting resin used.

Finally, the exposed portions of the anode lead terminal 13 and the cathode lead terminal 14 are bent along the exterior body 11. As a result, a portion of the anode lead terminal 13 and the cathode lead terminal 14 are arranged on the mounting surface of the exterior body 11.
Electrolytic capacitor 20 is manufactured by the above method.

INDUSTRIAL APPLICATION This invention can be utilized for an electrolytic capacitor, Suitably, it can be utilized for the electrolytic capacitor which uses a porous body for an anode body.

20: Electrolytic capacitor 10: Capacitor element 1: Anode body 2: Anode wire 2a: First part 2b: Second part 3: Dielectric layer 4: Solid electrolyte layer 5: Cathode layer 5a: Carbon layer 5b: Metal paste layer 6: Anode part 7: Cathode part 8: First adhesive 9: Second adhesive 11: Exterior body 13: Anode lead terminal 14: Cathode lead terminal 14a: Joint part S1: First main surface S2: Second main surface Main surface

Claims (7)

a capacitor element including an anode part and a cathode part;
an anode lead terminal electrically connected to the anode portion;
a cathode lead terminal electrically connected to the cathode portion;
a first adhesive material interposed between the cathode portion and the cathode lead terminal and having electrical conductivity;
an exterior body that covers the capacitor element with parts of the anode lead terminal and the cathode lead terminal exposed,
At least a part of the gap between the cathode part and the cathode lead terminal, where the first adhesive is not interposed, is filled with a second adhesive,
The first adhesive includes a conductive first filler,
The second adhesive includes an insulating second filler,
The average particle diameter of the second filler is smaller than the average particle diameter of the first filler . a capacitor element including an anode part and a cathode part;
an anode lead terminal electrically connected to the anode portion;
a cathode lead terminal electrically connected to the cathode portion;
a first adhesive material interposed between the cathode portion and the cathode lead terminal and having electrical conductivity;
an exterior body that covers the capacitor element with parts of the anode lead terminal and the cathode lead terminal exposed,
At least a part of the gap between the cathode part and the cathode lead terminal, where the first adhesive is not interposed, is filled with a second adhesive,
The first adhesive includes a first filler,
The second adhesive includes a second filler,
The average particle diameter of the second filler is smaller than the average particle diameter of the first filler. The surface of the cathode part has a first main surface in contact with the first adhesive, and a second main surface that intersects and adjoins the first main surface,
The cathode lead terminal extends along the first main surface and then is bent so as to extend along the second main surface,
The electrolytic capacitor according to claim 1 or 2 , wherein the second adhesive fills at least a portion of a gap between the cathode lead terminal and the second main surface. 4. The electrolytic capacitor according to claim 3 , wherein the first adhesive is not interposed between the cathode lead terminal and the second main surface. The anode part has an anode body,
5. The electrolytic capacitor according to claim 1 , wherein the anode body is a sintered body of metal particles having a valve action. The exterior body includes an insulating third filler,
The electrolytic capacitor according to any one of claims 1 to 5 , wherein the average particle diameter of the third filler is larger than the distance between the cathode portion and the cathode lead terminal. preparing a capacitor element having an anode section and a cathode section;
preparing an anode lead terminal and a cathode lead terminal;
forming an electrical connection between the anode part and the anode lead terminal, and forming an electrical connection between the cathode part and the cathode lead terminal;
a step of sealing the capacitor element with an exterior body,
The electrical connection between the cathode part and the cathode lead terminal is performed by interposing a conductive first adhesive between the cathode part and the cathode lead terminal,
further comprising the step of filling at least a portion of the gap between the cathode part and the cathode lead terminal where the first adhesive is not interposed with a second adhesive,
The first adhesive includes a first filler,
The second adhesive includes a second filler,
The method for manufacturing an electrolytic capacitor, wherein the second filler has an average particle diameter smaller than the first filler.

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