JP7038339B2 - How to manufacture electrolytic capacitors and electrolytic capacitors - Google Patents

Description

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

The electrolytic capacitor includes a laminated body in which a plurality of capacitor elements are laminated, and an exterior body that seals the laminated body. Each capacitor element has an anode foil having a dielectric layer formed on its surface and having an anode extraction portion and a cathode forming portion, and a cathode portion covering at least a part of the dielectric layer formed on the surface of the cathode forming portion. Have. Each of the plurality of anode extraction portions has an end face exposed from the exterior body, and the end faces of the plurality of anode extraction portions are each electrically connected to an external electrode (for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 2002-319522

Generally, the above-mentioned method for manufacturing an electrolytic capacitor includes a step a of preparing an anode foil in which a dielectric layer is formed on the surface and a plurality of regions having an anode extraction portion and a cathode forming portion are repeatedly provided, and a step a of the plurality of regions. A step b in which at least a part of the dielectric layer formed on the surface of the cathode forming portion is covered with the cathode portion to obtain an intermediate including a plurality of capacitor elements, and a step c in which the intermediate is divided into a plurality of condenser elements. The step d of stacking a plurality of capacitor elements to obtain a laminate, the step e of sealing the laminate and forming an exterior body in which the end faces of the plurality of anode extraction portions are exposed, and the step e of forming the end faces of the plurality of anode extraction portions are external. The step f of joining with the electrode is included.

However, in step c, since the intermediate is cut for each region, the number of cuts required for producing a plurality of laminated bodies is large. Further, in the step d, since a plurality of capacitor elements are stacked for each laminated body, the number of stacking required for producing the plurality of laminated bodies is large. Therefore, the productivity of the electrolytic capacitor is low.

One aspect of the present invention is a first step of preparing an anode foil in which a dielectric layer is formed on the surface and a plurality of regions having an anode extraction portion and a cathode forming portion are repeatedly provided, and the cathode in the plurality of regions. A second step of covering at least a part of the dielectric layer formed on the surface of the forming portion with a cathode portion to obtain an intermediate, and an anode laminated portion in which a plurality of the anode extraction portions are laminated using the intermediate. A third step of forming a plurality of laminates having a cathode laminated portion in which a plurality of the cathode portions are laminated to obtain a laminated intermediate, a fourth step of covering the laminated intermediate with an exterior body, and the anode laminated portion. A fifth step of cutting together with the exterior body to separate the anode laminated portion and a part of the exterior body to expose the end face of the anode extraction portion from the cut surface of the exterior body, and joining the end face to an external electrode. The present invention relates to a method for manufacturing an electrolytic capacitor, including the sixth step.

Another aspect of the present invention is an anode foil having an anode extraction portion and a cathode forming portion, a dielectric layer formed on the surface of the cathode forming portion, and a cathode portion covering at least a part of the dielectric layer. A laminated body in which a plurality of capacitor elements having the above-mentioned is laminated, and an exterior body for sealing the laminated body are provided, and at least one of the plurality of capacitor elements, the cathode extraction portion, has a notch portion. The present invention relates to an electrolytic capacitor, including an end portion, wherein the end portion has an end face exposed from the exterior body, and the end face is electrically connected to an external electrode.

According to the present invention, the productivity of the electrolytic capacitor can be increased.

It is a schematic sectional drawing which shows an example of the 1st intermediate obtained in the 2nd step of the manufacturing method of the electrolytic capacitor which concerns on one Embodiment of this invention. It is a schematic sectional drawing which shows another example of the 1st intermediate obtained in the 2nd step of the manufacturing method of the electrolytic capacitor which concerns on one Embodiment of this invention. It is a schematic sectional drawing which shows an example of the laminated intermediate obtained in the 3rd step of the manufacturing method of the electrolytic capacitor which concerns on one Embodiment of this invention. It is a schematic sectional drawing which shows another example of the laminated intermediate obtained in the 3rd step of the manufacturing method of the electrolytic capacitor which concerns on one Embodiment of this invention. It is the schematic which looked at the width direction of the band-shaped portion with still another example of the laminated intermediate obtained in the 3rd step of the manufacturing method of the electrolytic capacitor which concerns on one Embodiment of this invention. It is a schematic diagram of the main part seen from the side of the anode laminated part with an example of the laminated intermediate obtained in the 5th step of the manufacturing method of the electrolytic capacitor which concerns on one Embodiment of this invention. FIG. 6 is a schematic view of a main part of the laminated intermediate of FIG. 6 as viewed from above. FIG. 3 is a schematic view of a main part viewed from the side of the anode laminated portion as another example of the laminated intermediate obtained in the fifth step of the method for manufacturing an electrolytic capacitor according to an embodiment of the present invention. FIG. 3 is a schematic view of a main part of the laminated intermediate of FIG. 8 as viewed from above. It is a schematic sectional drawing which shows an example of the electrolytic capacitor which concerns on one Embodiment of this invention.

[Manufacturing method of electrolytic capacitors]
The method for manufacturing an electrolytic capacitor according to an embodiment of the present invention includes a first step of preparing an anode foil in which a dielectric layer is formed on the surface and a plurality of regions having an anode extraction portion and a cathode forming portion are repeatedly provided. The second step of covering at least a part of the dielectric layer formed on the surface of the cathode forming portion of a plurality of regions with the cathode portion to obtain an intermediate, and the anode in which a plurality of anode drawing portions are laminated using the intermediate. A third step of forming a plurality of laminates having a cathode laminated portion in which a plurality of laminated portions and a cathode portion are laminated to obtain a laminated intermediate, a fourth step of covering the laminated intermediate with an exterior body, and an exterior of the anode laminated portion. The fifth step of cutting together with the body to separate the anode laminated portion and a part of the exterior body to expose the end face of the anode extraction portion from the cut surface of the exterior body, and joining the end face of the anode extraction portion to the external electrode on the anode side. The sixth step is included.

Since a laminated intermediate having a plurality of laminated bodies is obtained in the third step, the laminated intermediate can be cut for each region (laminated body) and efficiently divided into a plurality of laminated bodies in a later step. Therefore, the number of cuts required to manufacture the plurality of laminates is reduced as compared with the case where the intermediate is cut for each region and divided into a plurality of capacitor elements and the plurality of capacitor elements are laminated to form the laminate. be able to. Further, in the third step, a plurality of laminated bodies can be efficiently manufactured by using an intermediate having a plurality of capacitor elements. Therefore, the number of stacking required for manufacturing the plurality of laminates can be reduced as compared with the case where a plurality of capacitor elements are stacked for each laminate. Therefore, the productivity of the electrolytic capacitor is increased.

(First step)
In the first step, an anode foil is prepared in which a dielectric layer is formed on the surface and a plurality of regions having an anode drawing portion and a cathode forming portion are repeatedly provided. The first step is, for example, a step of roughening the surface of the anode foil by etching or the like, a step of forming a dielectric layer on the roughened surface of the anode foil, and a step of repeatedly forming a plurality of regions. ,including.

The anode foil can include a valve acting metal, an alloy containing a valve acting metal, an intermetallic compound containing a valve acting metal, and the like. These materials can be used alone or in combination of two or more. As the valve acting metal, aluminum, tantalum, niobium, titanium and the like can be used.

The dielectric layer is formed, for example, by anodizing the valve acting metal on the surface of the anode foil by chemical conversion treatment or the like. The dielectric layer contains an oxide of the valve acting metal. For example, when aluminum is used as the valve acting metal, the dielectric layer contains aluminum oxide. The dielectric layer is formed, for example, along the roughened surface of the anode foil. The method for forming the dielectric layer is not limited to this, and it is sufficient that an insulating layer that functions as a dielectric can be formed. The dielectric layer may be formed on the surface of the cathode forming portion in at least a plurality of regions.

The plurality of regions are formed, for example, by punching the anode foil into a predetermined shape. The anode foil prepared in the first step preferably has a long strip-shaped portion and a plurality of regions arranged in a row so as to project from at least one end along the longitudinal direction of the strip-shaped portion. It is more preferred that the anode foil has a plurality of regions, each arranged in a row so as to project from both ends along the longitudinal direction of the strip. In this case, each of the plurality of regions has an anode extraction portion and a cathode forming portion in order from the strip-shaped portion side.

(Second step)
In the second step, at least a part of the dielectric layer formed on the surface of the cathode forming portion of the plurality of regions is covered with the cathode portion to obtain an intermediate. The cathode portion includes, for example, a solid electrolyte layer that covers at least a part of the dielectric layer and a cathode extraction layer that covers at least a part of the solid electrolyte layer.

The solid electrolyte layer contains, for example, a conductive polymer. As the conductive polymer, for example, polypyrrole, polythiophene, polyaniline and derivatives thereof can be used. The solid electrolyte layer can be formed, for example, by chemically polymerizing and / or electrolytically polymerizing the raw material monomer on the dielectric layer. Alternatively, it can be formed by applying a solution in which the conductive polymer is dissolved or a dispersion liquid in which the conductive polymer is dispersed to the dielectric layer. The solid electrolyte layer may contain a manganese compound.

The cathode extraction layer includes, for example, a carbon layer and a silver paste layer. The carbon layer may be conductive as long as it has conductivity, and can be formed by using a conductive carbon material such as graphite. The carbon layer is formed, for example, by applying a carbon paste to at least a part of the surface of the solid electrolyte layer. For the silver paste layer, for example, a composition containing silver powder and a binder resin (epoxy resin or the like) can be used. The silver paste layer is formed, for example, by applying a silver paste to the surface of the carbon layer. The configuration of the cathode extraction layer is not limited to this, and may be any configuration having a current collecting function.

(Third step)
In the third step, using the intermediate, a plurality of laminates having an anode laminated portion in which a plurality of anode extraction portions are laminated and a cathode laminated portion in which a plurality of cathode portions are laminated are formed to obtain a laminated intermediate. In the third step, for example, a plurality of intermediates are laminated so that the plurality of regions overlap in the same direction, or the intermediates are bent so that the plurality of regions overlap in the same direction. As a result, a plurality of laminated bodies are efficiently produced using the intermediate.

If the anode foil has multiple regions, each arranged in a row so as to project from both ends along the longitudinal direction of the strip, in the third step, one end along the longitudinal direction of the strip. It is possible to fold the intermediate in two with the widthwise midpoint of the strip as a crease so that the multiple regions on the side overlap each other on the other end side along the longitudinal direction of the strip. preferable. In this case, a plurality of laminates are efficiently produced using one intermediate.

Further, when the anode foil has a long strip-shaped portion and a plurality of regions arranged in a row so as to project from at least one end along the longitudinal direction of the strip-shaped portion, in the third step, the strip-shaped portion is formed. It is preferable to fold the intermediate in a zigzag manner with the boundary between the plurality of regions adjacent to each other in the longitudinal direction as a crease so that the plurality of regions on at least one end side along the longitudinal direction of the portions overlap each other. In this case, a plurality of laminates are efficiently produced using one intermediate.

It is preferable that at least one of the plurality of anode extraction portions of the anode laminated portion has notches or holes on at least one of both sides thereof. It is more preferable that the plurality of anode extraction portions of the anode laminated portion each have a pair of notches or holes on both sides. It is more preferable that the plurality of anode extraction portions of the anode laminated portion have a pair of notches and holes on both sides, respectively. In this case, in the fourth step described later, during injection molding or the like, the resin easily wraps around between the cathode forming portion side of the anode drawing portion and the anode drawing portions adjacent to each other in the anode laminated portion, and the outer body becomes the anode. It is easy to form in close contact with the drawer. Therefore, the intrusion of air into the electrolytic capacitor through the interface between the exterior body and the anode extraction portion is suppressed, and the reliability of the electrolytic capacitor is improved.

(4th step)
In the fourth step, the laminated intermediate (plurality of laminated bodies) is sealed with an exterior body. The exterior body preferably contains a cured product of a curable resin composition, and may contain a thermoplastic resin or a composition containing the same. By covering the laminated intermediate with the exterior body, a plurality of laminated bodies can be efficiently sealed with the exterior body.

The exterior body can be formed by using a molding technique such as injection molding. The exterior body is formed by filling a predetermined place with a curable resin composition or a thermoplastic resin (composition) so as to cover a laminated intermediate (a plurality of laminated bodies), for example, using a predetermined mold. can do.

The curable resin composition may contain a filler, a curing agent, a polymerization initiator, and / or a catalyst in addition to the curable resin. Examples of the curable resin include a photocurable resin and a thermosetting resin. The curing agent, polymerization initiator, catalyst and the like are appropriately selected depending on the type of the curable resin. The thermoplastic resin composition may contain a filler or the like in addition to the thermoplastic resin.

(Fifth step)
In the fifth step, the anode laminated portion (plurality of anode drawers) is cut together with the exterior body, the anode laminated portion and a part of the exterior body are separated, and the end faces of the plurality of anode drawer portions are exposed from the cut surface of the exterior body. Let me. As a result, the end faces of the anode extraction portions of the plurality of laminated bodies can be efficiently exposed from the exterior body by one cutting.

When the anode extraction portion has a pair of notches on both sides, in the fifth step, the anode laminated portion is cut so as to divide the pair of notches, respectively, and the anode extraction portion is exposed from the exterior body. At the same time, it is sufficient to form an end face having a width smaller than that of the rest of the anode extraction portion. In this case, the decrease in the adhesion between the anode drawing portion and the exterior body is suppressed. The remaining portion of the anode extraction portion refers to a region (a portion other than the end portion 45 of the anode extraction portion 43a in FIG. 7, which will be described later) that does not include the notch portion on the cathode portion side of the anode extraction portion.

When the anode extraction portion has a hole portion, in the fifth step, the anode laminated portion is cut so as to divide the hole portion, and two or more end faces exposed from the exterior body and separated from each other are formed in the anode extraction portion. do it. In this case, the decrease in the adhesion between the anode drawing portion and the exterior body is suppressed. A plurality of holes may be provided.

(6th step)
In the sixth step, the end faces of the plurality of anode extraction portions are joined to the external electrodes on the anode side, respectively. As a result, the end faces of the plurality of anode extraction portions are electrically connected to the external electrodes. In the sixth step, the end face of the anode drawing portion of the plurality of laminated bodies may be covered with an external electrode together with at least a part of the cut surface of the exterior body. As a result, the end faces of the anode extraction portions of the plurality of laminated bodies can be efficiently bonded to the external electrodes.

The external electrodes include a first electrode layer that covers a part of the surface of the exterior body (at least a part of the cut surface) together with the end faces of the plurality of anode extraction portions, and a second electrode layer formed on the surface of the first electrode layer. It is preferable to provide. In this case, the sixth step includes a step of covering a part of the surface of the exterior body together with the end faces of the plurality of anode extraction portions with the first electrode layer, and a step of forming the second electrode layer on the surface of the first electrode layer. It is preferable to include.

By covering a part of the surface of the exterior body with the first electrode layer together with the end surface of the anode extraction portion exposed from the exterior body, the formation of a natural oxide film on the end surface of the anode extraction portion is suppressed. From the viewpoint of suppressing the formation of the natural oxide film on the end surface of the anode extraction portion, it is preferable that the exterior body is covered with the first electrode layer so as to surround the end surface of the anode extraction portion.

The first electrode layer is preferably a metal layer. The metal layer comprises, for example, at least one selected from the group consisting of nickel, copper, zinc, tin, silver, and gold. For the formation of the first electrode layer, a film forming technique such as an electrolytic plating method, a electroless plating method, a sputtering method, a vacuum vapor deposition method, a chemical vapor deposition (CVD) method, a cold spray method, or a thermal spraying method may be used. By the above method, it is possible to easily form a first electrode layer that is joined to the end face of the anode drawing portion and is in close contact with a part of the surface of the exterior body.

The first electrode layer is covered with the second electrode layer. As a result, oxidative deterioration of the first electrode layer is suppressed. From the viewpoint of adhesion to the first electrode layer, the second electrode layer is preferably a conductive resin layer. The conductive resin layer includes, for example, a resin and a conductive material dispersed in the resin. The resin includes, for example, a cured product of a curable resin composition or a thermoplastic resin (composition). The conductive material includes, for example, at least one selected from the group consisting of silver, copper, and carbon.
Further, the second electrode layer may be a metal layer exemplified by the first electrode layer. For the formation of the second electrode layer, the film forming technique exemplified in the first electrode layer may be used.

Hereinafter, an example of an intermediate produced in the second step of the method for manufacturing an electrolytic capacitor according to an embodiment of the present invention will be described with reference to FIG. FIG. 1 is a schematic front view showing an example of an intermediate produced in the second step. The broken line C in FIG. 1 indicates a portion where the anode laminated portion (plurality of anode extraction portions 3a) is cut in the fifth step.

The intermediate 10a includes an anode foil 1 having a long strip 2 and a plurality of regions 3 arranged in a row so as to project from both ends of the strip 2 along the longitudinal direction. .. Each of the plurality of regions 3 has an anode extraction portion 3a and a cathode forming portion 3b in order from the strip-shaped portion 2 side. The surface of the anode foil 1 is roughened, and a dielectric layer (not shown) is formed on the surface of the anode foil 1. At least a part of the cathode forming portion 3b of the plurality of regions 3 is covered with the cathode portion 4. In this way, the capacitor elements 5 are formed in the plurality of regions 3 of the intermediate 10a, respectively.

As shown in FIG. 1, each of the plurality of anode extraction portions 3a has a pair of notches 6 on both sides. In this case, in the fifth step, the anode laminated portion may be cut so as to divide each pair of notch portions 6. As a result, the anode extraction portion 43a shown in FIG. 7, which will be described later, is formed.

Further, as another example of the intermediate produced in the second step, as in the intermediate 10b shown in FIG. 2, the plurality of anode extraction portions 3a may each have a hole portion 7. The intermediate body 10b has the same configuration as the intermediate body 10a except that the anode drawing portion 3a is provided with a hole portion 7 instead of the pair of cutout portions 6. In this case, in the fifth step, the anode laminated portion may be cut along the broken line C in FIG. 2 so as to divide each hole portion 7. As a result, the anode extraction portion 53a shown in FIG. 9, which will be described later, is formed. In FIG. 2, one hole is provided in the anode drawer 3a, but a plurality of holes may be provided in the anode drawer 3a along the broken line C.

Hereinafter, an example of the laminated intermediate obtained by using the intermediate 10a in the third step will be described with reference to FIG. FIG. 3 shows a cross section (a cross section passing through the notch 6 of the anode extraction portion 3a) along the width direction of the strip-shaped portion of the laminated intermediate. The broken line C in FIG. 3 indicates a portion where the anode laminated portion 12 is cut in the fifth step.

The laminated intermediate 11 shown in FIG. 3 is obtained by stacking a plurality of intermediates 10a in the third step. In the laminated intermediate 11, a plurality of laminated bodies 11a in which a plurality of capacitor elements 5 are laminated are formed. The laminated body 11a has an anode laminated portion 12 in which a plurality of anode extraction portions 3a are laminated, and a cathode laminated portion 13 in which a plurality of cathode portions 4 (including a cathode forming portion 3b inside) are laminated. The cathode portions 4 adjacent to each other in the cathode laminated portion 13 may be joined by using, for example, a conductive adhesive containing silver or the like.

Hereinafter, another example of the laminated intermediate obtained by using the intermediate 10a in the third step will be described with reference to FIG. 4. FIG. 4 shows a cross section of the strip of the laminated intermediate along the width direction. The broken line C in FIG. 4 indicates a portion where the anode laminated portion 22 is cut in the fifth step.

The laminated intermediate 21 shown in FIG. 4 is obtained by bending the intermediate 10a of FIG. 1 in two in the third step with the intermediate point in the width direction of the strip portion 2 (broken line F1 shown in FIG. 1) as a crease. Be done. In the two-folded intermediate 10a, the plurality of regions 3 on one end side along the longitudinal direction of the strip 2 are combined with the plurality of regions 3 on the other end side along the longitudinal direction of the strip 2. They overlap each other.

In the laminated intermediate 21, a plurality of laminated bodies 21a in which two capacitor elements 5 are laminated are formed. The laminated body 21a has an anode laminated portion 22 in which two anode extraction portions 3a are laminated, and a cathode laminated portion 23 in which two cathode portions 4 (including a cathode forming portion 3b inside) are laminated. Although one intermediate is used in FIG. 4, a plurality of intermediates may be bent to form a plurality of laminated intermediates 21, and a plurality of laminated intermediates 21 may be further laminated.

Hereinafter, another example of the laminated intermediate obtained by using the intermediate 10a in the third step will be described with reference to FIG. FIG. 5 is a view of the laminated intermediate as viewed from the width direction of the strip-shaped portion.

In the laminated intermediate 31 shown in FIG. 5, in the third step, the intermediate 10a of FIG. 1 is folded at a boundary (broken line F2 shown in FIG. 1) between a plurality of regions 3 adjacent to each other in the longitudinal direction of the band-shaped portion 2. It is obtained by folding it in a zigzag manner. In the zigzag-folded intermediate 10a, the plurality of regions 3 on one end side along the longitudinal direction of the band-shaped portion 2 overlap each other, and the plurality of regions 3 on the other end side along the longitudinal direction of the strip-shaped portion 2 overlap. Overlapping each other

In the laminated intermediate 31, two laminated bodies 31a are formed via the zigzag-folded strips 2. In the laminated body 31a, a plurality of capacitor elements 5 are laminated. That is, the laminated body 31a has an anode laminated portion in which a plurality of anode extraction portions 3a are laminated, and a cathode laminated portion in which a plurality of cathode portions 4 (including a cathode forming portion 3b inside) are laminated. Although one intermediate is used in FIG. 5, a plurality of intermediates may be bent to form a plurality of laminated intermediates 31, and a plurality of laminated intermediates 31 may be further laminated.

Hereinafter, an example of the laminated intermediate obtained in the fifth step will be described with reference to FIGS. 6 and 7. FIG. 6 is a schematic view of a main part of the laminated intermediate as viewed from the side of the anode laminated portion. FIG. 6 shows cutting when the laminated intermediate 11 (at least the anode laminated portion 12 and the cathode laminated portion 13) of FIG. 3 is covered with the exterior body and the anode laminated portion 12 is cut together with the exterior body along the broken line C of FIG. Show the surface. The cut surface constitutes the first side surface 69a of FIG. 10, which will be described later. FIG. 7 is a schematic view of a main part of the laminated intermediate of FIG. 6 as viewed from above.

As shown in FIGS. 6 and 7, the laminated intermediate 41 includes a plurality of laminated bodies 41a and an exterior body 49 that covers the plurality of laminated bodies 41a. The laminated intermediate 41 covers the laminated intermediate 11 (at least the anode laminated portion 12 and the cathode laminated portion 13) of FIG. 3 with an exterior body, and cuts the anode laminated portion 12 together with the exterior body along the broken line C of FIG. Obtained at. By dividing the laminated intermediate 41 into each laminated body 41a, a plurality of laminated bodies 41a covered with the exterior body 69 shown in FIG. 10 to be described later can be obtained.

The laminated body 41a is a cathode in which an anode laminated portion (the anode laminated portion 42 in FIG. 10 described later) in which a plurality of anode extraction portions 43a are laminated and a plurality of cathode portions 4 (including a cathode forming portion 3b inside) are laminated. It has a laminated portion (cathode laminated portion 13 in FIG. 10 described later). In the fifth step, the anode laminated portion (plurality of the anode laminated portions 43a) cuts the anode laminated portion 12 so as to divide the pair of notched portions 6 of the plurality of anode drawn out portions 3a (the anode laminated portion 12 is shown in the figure). (Cut along the dashed line C of 3).

The anode extraction portion 43a includes an end portion 45 having a pair of notches 46 at both ends, and the end portion 45 is exposed from the exterior body 49 and is more than the remaining portion (a portion other than the end portion 45) of the anode extraction portion 43a. It has an anode 48 with a small width. The end portion 45 of the anode extraction portion 43a refers to a region (hatched portion in FIG. 7) opposite to the cathode portion 4 including the notch portion 46.

The end faces 48 of the anode extraction portions 43a of the plurality of laminated bodies 41a are each exposed from the cut surface of the exterior body 49. In this case, in the sixth step, the cut surface of the exterior body 49 and the end faces 48 of the plurality of laminated bodies 41a may be collectively covered with the external electrodes. After that, when the laminated intermediate 41 is divided into the laminated bodies 41a, the external electrode may be divided together with the exterior body 49. In this case, the productivity of the electrolytic capacitor is further increased. The end surface 4a of the cathode portion 4 of the plurality of laminated bodies 41a is exposed from the side surface opposite to the cut surface of the exterior body 49, respectively.

Hereinafter, another example of the laminated intermediate obtained in the fifth step will be described with reference to FIGS. 8 and 9. FIG. 8 is a schematic view of a main part of the laminated intermediate as viewed from the side of the anode laminated portion. FIG. 9 is a schematic view of a main part of the laminated intermediate as viewed from above.

As the laminated intermediate 51, the intermediate 10b having the hole 7 is used in the third step, and the laminated intermediate 41 is cut except that the anode laminated portion is cut so as to divide the holes of the plurality of anode extraction portions in the fifth step. It is obtained by the same method as. The laminated intermediate 51 includes a plurality of laminated bodies 51a and an exterior body 59 that covers the plurality of laminated bodies 51a. The laminated body 51a has an anode laminated portion in which a plurality of anode extraction portions 53a are laminated, and a cathode laminated portion in which a plurality of cathode portions 4 (including a cathode forming portion 3b inside) are laminated. In the fifth step, the anode laminated portion in which the plurality of anode extraction portions 53a are laminated cuts the anode laminated portion so as to divide the hole portion 7 of the plurality of anode extraction portions 3a (each anode extraction portion is shown in FIG. 2). (Cut along the dashed line C).

The anode lead-out portion 53a includes an end portion 55 having a notch 57 in the center, and the end portion 55 has an end face 58 exposed from the exterior body 59. The end face 58 is composed of a pair of end faces 58a and 58b that are separated from each other. The central portion of the end portion 55 provided with the notch portion 57 refers to an arbitrary position between both ends of the end portion 55. Further, the end portion 55 of the anode extraction portion 53a refers to a region (hatched portion in FIG. 9) opposite to the cathode portion 4 including the notch portion 57.

[Electrolytic capacitor]
The electrolytic capacitor according to the embodiment of the present invention includes a laminated body in which a plurality of capacitor elements are laminated, and an exterior body that seals the laminated body. Each capacitor element has an anode foil having an anode extraction portion and a cathode forming portion, a dielectric layer formed on the surface of the cathode forming portion, and a cathode portion covering at least a part of the dielectric layer. At least one anode extension of the plurality of capacitor elements includes an end having a notch. The end portion has an end face exposed from the exterior body, and the end face is electrically connected to an external electrode. A dielectric layer may also be formed on the surface of the anode extraction portion.

The notch provided at the end of the anode drawer is derived from the notch or hole provided in the anode drawer of a plurality of regions of the intermediate used in the above manufacturing method. That is, the above electrolytic capacitor uses an intermediate in which the anode extraction portions of the plurality of regions have notches at at least one of both ends thereof, and an intermediate in which the anode extraction portions of the plurality of regions have holes. It is obtained by the manufacturing method of. When the above intermediate is used, in the fourth step, during injection molding or the like, the resin easily wraps around between the cathode forming portion side of the anode drawing portion and the anode drawing portions adjacent to each other in the anode laminated portion, and the exterior The body is formed in close contact with the anode drawer. Therefore, the electrolytic capacitor obtained by the above manufacturing method suppresses the intrusion of air into the electrolytic capacitor through the interface between the exterior body and the anode extraction portion, and the reliability is improved.

Hereinafter, an example of the electrolytic capacitor according to the embodiment of the present invention will be described with reference to FIG. FIG. 10 is a schematic cross-sectional view of an electrolytic capacitor provided with the laminate 41a of FIGS. 6 and 7.

The electrolytic capacitor 61 includes a laminated body 41a in which a plurality of capacitor elements 5 are laminated. The capacitor element 5 has at least one of an anode foil having an anode drawing portion 43a and a cathode forming portion 3b having a dielectric layer (not shown) formed on the surface thereof and a dielectric layer formed on the surface of the cathode forming portion 3b. It has a cathode portion 4 that covers the portions.

The electrolytic capacitor 61 includes an exterior body 69 that seals the laminated body 41a. The exterior body 69 has a substantially rectangular parallelepiped outer shape, and the electrolytic capacitor 61 also has a substantially rectangular parallelepiped outer shape. The exterior body 69 has a first side surface 69a and a second side surface 69b opposite to the first side surface 69a. The ends of the plurality of anode extraction portions 43a (end portions 45 in FIG. 7) are each exposed from the first side surface 69a of the exterior body 69 and have the first side surface 69a and the end surface 48 flush with each other.

The end faces 48 of the plurality of anode extraction portions 43a are electrically connected to the external electrodes 62 on the anode side, respectively. The external electrode 62 on the anode side includes a first electrode layer 62a that covers a plurality of end faces 48 and a first side surface 69a of the exterior body 69, and a second electrode layer 62b formed on the surface of the first electrode layer 62a. Have.

When the end face 48 of the plurality of anode extraction portions 43a is connected to the external electrode 62 on the anode side, it is not necessary to bundle the plurality of anode extraction portions, and it is necessary to secure a length for bundling the plurality of anode extraction portions. There is no. Therefore, as compared with the case where a plurality of anode extraction portions are bundled, the ratio of the anode extraction portion to the anode foil of the capacitor element can be reduced to increase the capacity.

The electrolytic capacitor 61 includes an external electrode 63 on the cathode side that is electrically connected to the cathode portion 4. Specifically, the plurality of cathode portions 4 have end faces 4a exposed from the second side surface 69b of the exterior body 69. The end face 4a is flush with the second side surface 69b. The end faces 4a of the plurality of cathode portions 4 are joined to the external electrodes 63 on the cathode side, respectively. The cathode-side external electrode 63 is formed on the surfaces of the cathode-side first electrode layer 63a and the cathode-side first electrode layer 63a that cover the second side surface 69b of the exterior body 69 together with the end faces of the plurality of end portions 4a. It has a second electrode layer 63b on the cathode side.

In the plurality of capacitor elements 5, the cathode portions 4 adjacent to each other in the stacking direction are electrically connected via a conductive adhesive layer (not shown). For example, a conductive adhesive is used to form the adhesive layer. The adhesive layer contains, for example, silver.

An insulating separation layer (not shown) may be arranged on the portion of the anode extraction portion 43a adjacent to the cathode portion 4 so as to cover the surface of the anode extraction portion 43a. The separation layer restricts the contact between the cathode portion 4 and the anode extraction portion 43a.

The electrolytic capacitor according to the present invention can be used in various applications requiring high capacity.

1: Anode foil 2: Band-shaped part 3: Region 3a, 43a, 53a: Anode extraction part 3b: Electrode forming part 4: Cathode part 5: Condenser element, 6: Notch part, 7: Hole part 10,a, 10b: Intermediate, 11,21,31,41,51: Laminated intermediate, 11a, 21a, 31a, 41a, 51a: Laminated, 12,22,42: Anode laminated part, 13,23: Cathode Laminated portion, 45, 55: End portion of anode extraction portion, 46, 57: Notch portion of anode extraction portion, 48, 58, 58a, 58b: End face of anode extraction portion, 49, 59, 69: Exterior body, 61 : Electrolytic capacitor, 62: External electrode on the anode side, 62a: First electrode layer on the anode side, 62b: Second electrode layer on the anode side, 63: External electrode on the cathode side, 63a: First electrode layer on the cathode side, 63b: Second electrode layer on the cathode side, 69a: First side surface of the exterior body, 69b: Second side surface of the exterior body

Claims (11)

The first step of preparing an anode foil in which a dielectric layer is formed on the surface and a plurality of regions having an anode drawing portion and a cathode forming portion are repeatedly provided.
The second step of covering at least a part of the dielectric layer formed on the surface of the cathode forming portion of the plurality of regions with the cathode portion to obtain an intermediate, and the second step.
A third step of forming a plurality of laminates having an anode laminated portion in which a plurality of the anode extraction portions are laminated and a cathode laminated portion in which a plurality of cathode portions are laminated by using the intermediate, and obtaining a laminated intermediate.
The fourth step of covering the laminated intermediate with an exterior body, and
The anode laminated portion is cut together with the exterior body to separate the anode laminated portion and a part of the exterior body, and the first end surface of the anode drawing portion is exposed from the cut surface of the exterior body to expose the first end surface of the anode drawing portion of the exterior body. The fifth step of exposing the second end surface of the cathode portion from the side surface on the opposite side of the cut surface and making the side surface on the opposite side of the cut surface and the second end surface of the cathode portion flush with each other.
The sixth step of joining the first end surface to the external electrode and
How to manufacture electrolytic capacitors, including. The method for manufacturing an electrolytic capacitor according to claim 1, wherein the laminated intermediate is obtained by bending the intermediate in the third step. The anode foil has a long strip and a plurality of regions arranged in a row so as to project from at least one end of the strip along the longitudinal direction, claim 1 or 2. The method for manufacturing an electrolytic capacitor described in 1. The anode extraction portion has a pair of notches on both sides and has a pair of notches.
In the fifth step, the anode laminated portion is cut so as to divide the pair of notches, respectively, and the first end surface having a width smaller than the rest of the anode drawer portion is formed in the anode drawer portion. The method for manufacturing an electrolytic capacitor according to any one of claims 1 to 3. The anode extraction portion has a hole portion and has a hole portion.
3. The method for manufacturing an electrolytic capacitor according to item 1. The external electrode includes a first electrode layer and a second electrode layer, and the external electrode includes a first electrode layer and a second electrode layer.
The sixth step includes a step of covering at least a part of the cut surface of the exterior body together with the first end surface with the first electrode layer, and a step of forming the second electrode layer on the surface of the first electrode layer. , The method for manufacturing an electrolytic capacitor according to any one of claims 1 to 5. A plurality of capacitor elements having an anode foil having an anode drawing portion and a cathode forming portion, a dielectric layer formed on the surface of the cathode forming portion, and a cathode portion covering at least a part of the dielectric layer. Laminated laminates and
The exterior body for sealing the laminated body is provided.
The anode extraction portion of at least one of the plurality of capacitor elements includes an end portion having a notch portion.
The end portion has a first end surface exposed from the first side surface of the exterior body.
The first end surface is electrically connected to an external electrode, and the first end surface is electrically connected to the external electrode.
The cathode portion has a second end surface exposed from a second side surface opposite to the first side surface of the exterior body.
The second end surface is an electrolytic capacitor that is flush with the second side surface of the exterior body. The end has a pair of notches at both ends.
The electrolytic capacitor according to claim 7, wherein the width of the first end surface is smaller than the width of the remaining portion of the anode extraction portion. The electrolytic capacitor according to claim 7, wherein the end portion has the notch portion in the central portion and has two or more first end faces separated from each other. 7. The external electrode has a first electrode layer that covers the first end surface and a part of the surface of the exterior body, and a second electrode layer formed on the surface of the first electrode layer. The electrolytic capacitor according to any one of 9 to 9. The electrolytic capacitor according to any one of claims 7 to 10, wherein the notch portion has a width increasing along a curve from the cathode portion side toward the first end surface of the anode extraction portion.

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