JP7419791B2 - solid electrolytic capacitor - Google Patents

Description

The present invention relates to solid electrolytic capacitors.

A solid electrolytic capacitor includes a valve metal base having a dielectric layer on the surface of the base made of a valve metal such as aluminum, and a cathode layer including a solid electrolyte layer provided on the dielectric layer.

For example, Patent Document 1 describes (A) a step of preparing a first sheet comprising a valve metal base on which a dielectric layer is formed and a solid electrolyte layer provided on the dielectric layer; B) preparing a second sheet made of metal foil; (C) covering the first sheet with an insulating material; (D) providing a conductor layer on the solid electrolyte layer of the first sheet. (E) producing a laminated sheet by laminating the first sheet and the second sheet; (F) filling the through holes of the laminated sheet with a sealing material to form a laminated block. (G) producing a plurality of element stacks by cutting the stacked block body; (H) forming a first external electrode and a second external electrode. A method of manufacturing a solid electrolytic capacitor is disclosed.

JP2019-79866A

According to Patent Document 1, a laminated sheet obtained by laminating a first sheet and a second sheet is cut to produce a plurality of element laminates, and external electrodes are formed on the element laminates. It is said that a plurality of solid electrolytic capacitors can be efficiently manufactured by using the method.

However, when a solid electrolytic capacitor in which multiple capacitor elements are stacked is heated by heat treatment such as reflow, large thermal stress is applied to the bottom side of the solid electrolytic capacitor, and thermal stress is also applied to the top side of the solid electrolytic capacitor. join. As a result, a problem arises in that the laminated capacitor elements peel off and the equivalent series resistance (ESR) changes.

In particular, in solid electrolytic capacitors in which a plurality of capacitor elements are laminated on a substrate made of glass epoxy resin or the like, the above problem becomes significant because the capacitor elements are likely to peel off due to large warpage of the substrate.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a solid electrolytic capacitor whose ESR changes less due to thermal stress.

The solid electrolytic capacitor of the present invention includes a resin molded body, a first external electrode, and a second external electrode. The resin molded body includes a laminate in which a plurality of capacitor elements are stacked, and a sealing resin that seals around the laminate. The resin molded body has a bottom face and a top face facing each other in a thickness direction parallel to the lamination direction of the capacitor element, a first end face and a second end face facing each other in a length direction perpendicular to the lamination direction, and and a first side surface and a second side surface facing each other in a width direction perpendicular to the length direction. The first external electrode is provided on the first end surface of the resin molded body. The second external electrode is provided on the second end surface of the resin molded body. The capacitor element includes an anode having a dielectric layer on its surface, and a cathode facing the anode with the dielectric layer interposed therebetween. The anode includes a valve metal base having a porous portion on the surface of the core. The cathode includes a cathode extraction layer. The first external electrode is electrically connected to the valve metal base exposed from the first end surface. The second external electrode is electrically connected to the cathode extraction layer exposed from the second end surface. Between at least one set of capacitor elements adjacent to each other in the stacking direction, there is a non-contact area where the cathode of one capacitor element and the cathode of the other capacitor element do not come into contact; There is a contact area where the cathode of the capacitor element contacts the cathode of the other capacitor element.

According to the present invention, it is possible to provide a solid electrolytic capacitor with little change in ESR due to thermal stress.

FIG. 1 is a perspective view schematically showing an example of a solid electrolytic capacitor of the present invention. FIG. 2 is a cross-sectional view of the solid electrolytic capacitor shown in FIG. 1 taken along line II-II. FIG. 3 is a plan view of the resin molded body shown in FIG. 2 viewed from the thickness direction. FIG. 4 is a cross-sectional view schematically showing another example of the solid electrolytic capacitor of the present invention.

The solid electrolytic capacitor of the present invention will be explained below.
However, the present invention is not limited to the following configuration, and can be modified and applied as appropriate without changing the gist of the present invention. Note that the present invention also includes a combination of two or more desirable configurations of each embodiment described below.

[Solid electrolytic capacitor]
FIG. 1 is a perspective view schematically showing an example of a solid electrolytic capacitor of the present invention.
A solid electrolytic capacitor 1 shown in FIG. 1 is a surface-mounted solid electrolytic capacitor, and includes a resin molded body 9, a first external electrode 11, and a second external electrode 13.

The resin molded body 9 has a rectangular parallelepiped shape. The resin molded body 9 has a first end surface 9a and a second end surface 9b facing each other in the length direction (L direction), a bottom surface 9c and a top surface 9d facing each other in the thickness direction (T direction), and a width direction (W direction). It has a first side surface 9e and a second side surface 9f facing each other. Here, the length direction, width direction, and thickness direction are orthogonal to each other.

A first external electrode 11 is provided on the first end surface 9a, and a second external electrode 13 is provided on the second end surface 9b.

The bottom surface 9c is a surface on which the solid electrolytic capacitor 1 is mounted.

In this specification, the surface along the length direction and thickness direction of a solid electrolytic capacitor or resin molded body is referred to as the LT surface, and the surface along the length direction and width direction is referred to as the LW surface. The plane along the direction is called the WT plane. Therefore, in the solid electrolytic capacitor 1 shown in FIG. The second side surface 9f is the LT surface.

FIG. 2 is a cross-sectional view of the solid electrolytic capacitor shown in FIG. 1 taken along line II-II.
The resin molded body 9 includes a laminate 30 in which a plurality of capacitor elements 20 are stacked, and a sealing resin 8 that seals the periphery of the laminate 30. In the example shown in FIG. 2, eight capacitor elements 20A, 20B, 20C, 20D, 20E, 20F, 20G, and 20H are stacked. The stacking direction of the capacitor element 20 is parallel to the thickness direction (T direction) of the resin molded body 9.

In the example shown in FIG. 2, a support substrate 9g is provided at the bottom of the resin molded body 9, and the bottom surface of the support substrate 9g is the bottom surface 9c of the resin molded body 9. The support substrate 9g is provided to integrate the laminate 30 of the capacitor element 20.

Capacitor element 20 includes an anode 3 having a dielectric layer 5 on its surface, and a cathode 7 facing the anode 3 with the dielectric layer 5 interposed therebetween. In the laminate 30, the stacked capacitor elements 20 may be bonded to each other via a conductive adhesive (not shown). In that case, the conductive adhesive is also considered to be part of the cathode 7.

The anode 3 constituting the capacitor element 20 includes a valve metal base 3a. The valve metal base 3a has a porous portion such as an etched layer on the surface of the core portion. A dielectric layer 5 is provided on the surface of the porous portion.

The valve metal base 3a is drawn out to the first end surface 9a of the resin molded body 9. The first external electrode 11 provided on the first end surface 9a of the resin molded body 9 is electrically connected to the valve metal base 3a exposed from the first end surface 9a.

The cathode 7 constituting the capacitor element 20 includes a solid electrolyte layer 7a formed on the dielectric layer 5, a conductive layer 7b formed on the solid electrolyte layer 7a, and a cathode extraction layer formed on the conductive layer 7b. 7c.

The cathode drawing layer 7c is drawn out to the second end surface 9b of the resin molded body 9. The second external electrode 13 provided on the second end surface 9b of the resin molded body 9 is electrically connected to the cathode extraction layer 7c exposed from the second end surface 9b.

Between a pair of capacitor elements 20D and 20E that are adjacent to each other in the stacking direction of the capacitor elements 20, that is, the thickness direction (T direction) of the resin molded body 9, there is a cathode 7 of one capacitor element 20D and a cathode 7 of the other capacitor element 20E. There are a non-contact region 41 in which the cathode 7 of the capacitor element 20D does not contact, and a contact region 42 that surrounds the non-contact region 41 and in which the cathode 7 of one capacitor element 20D and the cathode 7 of the other capacitor element 20E are in contact. In the contact area 42, the cathodes 7 are in mechanical and electrical contact with each other, and in the non-contact area 41, the cathodes 7 are not in mechanical or electrical contact with each other.

In the example shown in FIG. 2, a cathode extraction layer 7c constituting a part of the cathode 7 is located in the capacitor element 20D, and a non-contact region 41 is formed between it and the cathode 7 of the capacitor element 20E on the opposite side. Note that the cathode extraction layer 7c forming a part of the cathode 7 may be located in the capacitor element 20E, and the non-contact region 41 may be formed between it and the cathode 7 of the capacitor element 20D on the opposite side.

On the other hand, in the vicinity of the first end surface 9a and the second end surface 9b of the resin molded body 9, a contact area 42 is formed by the cathode 7 of the capacitor element 20D and the cathode 7 of the capacitor element 20E coming into contact with each other.

By providing a non-contact region of the cathode between the capacitor elements, thermal stress caused by heating during manufacturing, reflow, etc. of the solid electrolytic capacitor can be alleviated. As a result, the laminated capacitor elements are less likely to peel off, so changes in ESR due to thermal stress can be reduced.

Furthermore, by providing the cathode contact area to surround the non-contact area, the laminated capacitor elements are less likely to peel off no matter which direction thermal stress is applied, making it possible to alleviate thermal stress. can.

FIG. 3 is a plan view of the resin molded body shown in FIG. 2 viewed from the thickness direction.
As shown in FIG. 3, the non-contact area 41 surrounded by the contact area 42 is preferably located at the center of the resin molded body 9 in the length direction (L direction) and width direction (W direction). . In this case, thermal stress applied from the bottom and top sides of the solid electrolytic capacitor can be effectively alleviated.

The size of the non-contact area 41 should be 1/3 or more and 2/3 or less of the length direction (L direction) and width direction (W direction) dimensions of the resin molded body 9 for relaxation of thermal stress and resin molding. This is preferable in terms of achieving both good adhesion to the body. Note that when adjacent capacitor elements 20 are bonded to each other via a conductive adhesive, the conductive adhesive may be provided in the same planar shape as the contact area 42 .

In this specification, the lengthwise and widthwise central portions of the resin molded body refer to the region including the lengthwise and widthwise centers of the resin molded body. Preferably, in the length direction of the resin molded object, it is located inside a distance of 1/2 or less of the distance from the center of the resin molded object to the first end surface or the second end surface, and in the width direction of the resin molded object, It means a region located inside a distance of 1/2 or less of the distance from the center of the resin molded body to the first side surface or the second side surface.

As shown in FIG. 2, the non-contact area 41 is located between a pair of capacitor elements (capacitor elements 20D and 20E in FIG. 2) closest to the center of the resin molded body 9 in the thickness direction (T direction). It is preferable that you do so. In this case, thermal stress applied from the bottom and top sides of the solid electrolytic capacitor can be effectively alleviated.

The arrangement, number, shape, etc. of the non-contact areas 41 are not limited to the examples shown in FIGS. 2 and 3. For example, the planar shape of the non-contact area 41 viewed from the thickness direction (T direction) of the resin molded body 9 includes an ellipse, a circle, a rectangle, and the like. The planar shape of the non-contact area 41 may be symmetrical or asymmetrical.

The non-contact area 41 may exist between any one set of capacitor elements adjacent in the stacking direction, or between two or more sets of capacitor elements adjacent in the stacking direction. For example, the non-contact area 41 may exist not only between capacitor elements 20D and 20E, but also between capacitor elements 20A and 20B, between capacitor elements 20B and 20C, etc. Further, the non-contact area 41 may not exist between the capacitor elements 20D and 20E.

In the example shown in FIG. 3, one non-contact area 41 exists between one set of capacitor elements, but a plurality of non-contact areas 41 may exist between one set of capacitor elements.

It is preferable that the non-contact area 41 is a void. Alternatively, at least a portion of the non-contact area 41 may be filled with an insulating material. Since damage to each capacitor element itself due to thermal stress can be easily reduced, it is more preferable that the non-contact area 41 is a void.

FIG. 4 is a cross-sectional view schematically showing another example of the solid electrolytic capacitor of the present invention.
In the solid electrolytic capacitor 1A shown in FIG. 4, a part of the non-contact area 41 is filled with an insulating material 43.

Examples of the insulating material 43 include insulating resin. Examples of the insulating resin include epoxy resin, silicone resin, and phenol resin. Preferably, the insulating material 43 has adhesive properties.

From the viewpoint of stress relaxation, the insulating resin constituting the insulating material 43 is preferably a resin having a smaller coefficient of linear expansion than the sealing resin 8 constituting the resin molded body 9.

Note that although the entire non-contact area 41 may be filled with the insulating material 43, it is preferable that the insulating material 43 is filled so that a gap remains in a part of the non-contact area 41.

The valve metal base 3a is made of a valve metal that exhibits so-called valve action. Examples of valve metals include simple metals such as aluminum, tantalum, niobium, titanium, zirconium, magnesium, and silicon, and alloys containing these metals. Among these, aluminum or aluminum alloy is preferred.

Although the shape of the valve metal base 3a is not particularly limited, it is preferably flat and more preferably foil-shaped.

Since the porous portion provided on the surface of the valve metal base 3a increases the specific surface area of the valve metal base 3a, the capacitance of the solid electrolytic capacitor 1 can be increased. Examples of the porous portion include an etching layer formed on the surface of the valve metal base 3a, a porous layer formed on the surface of the valve metal base 3a by printing and sintering, and the like. When the valve metal is aluminum or an aluminum alloy, it is preferably an etched layer, and when it is titanium or a titanium alloy, it is preferably a porous layer.

Although the thickness of the valve metal base 3a is not particularly limited, the thickness of the core excluding the porous portion is preferably 5 μm or more and 100 μm or less. Further, the thickness of the porous portion (thickness on one side) is preferably 5 μm or more and 200 μm or less.

The thickness of the valve metal base 3a described above is the thickness of the inside of the valve metal base 3a excluding the portion exposed from the end surface.

The dielectric layer 5 is preferably made of an oxide film of the valve metal. For example, when aluminum foil is used as the valve metal base 3a, the dielectric layer 5 is formed by anodizing in an aqueous solution containing boric acid, phosphoric acid, adipic acid, or their sodium salts, ammonium salts, etc. An oxide film can be formed.

The dielectric layer 5 is formed along the surface of the porous portion, thereby forming pores (recesses). The thickness of the dielectric layer 5 is designed in accordance with the withstand voltage and capacitance required of the solid electrolytic capacitor, and is preferably 10 nm or more, and preferably 100 nm or less.

Furthermore, from the viewpoint of increasing the manufacturing efficiency of the solid electrolytic capacitor, a chemically formed foil that has been subjected to a chemical conversion treatment in advance may be used as the valve metal base 3a on which the dielectric layer 5 is formed.

Examples of the material constituting the solid electrolyte layer 7a include conductive polymers having skeletons of pyrroles, thiophenes, anilines, and the like. Examples of conductive polymers with thiophene skeletons include PEDOT [poly(3,4-ethylenedioxythiophene)], and PEDOT:PSS complexed with polystyrene sulfonic acid (PSS) as a dopant. It may be.

The solid electrolyte layer 7a is formed by forming a polymer film such as poly(3,4-ethylenedioxythiophene) on the surface of the dielectric layer 5 using, for example, a treatment liquid containing a monomer such as 3,4-ethylenedioxythiophene. The dielectric layer 5 may be formed by a method of forming the dielectric layer 5, or a method of applying a dispersion of a polymer such as poly(3,4-ethylenedioxythiophene) to the surface of the dielectric layer 5 and drying it. Note that after forming the solid electrolyte layer for the inner layer that fills the pores (recesses), it is preferable to form the solid electrolyte layer for the outer layer that covers the entire dielectric layer.

The solid electrolyte layer 7a can be formed in a predetermined area by applying the above treatment liquid or dispersion liquid onto the dielectric layer 5 by sponge transfer, screen printing, spray coating, dispenser, inkjet printing, etc. . The thickness of the solid electrolyte layer 7a is preferably 2 μm or more, and preferably 20 μm or less.

The conductive layer 7b is provided to electrically and mechanically connect the solid electrolyte layer 7a and the cathode extraction layer 7c. The conductive layer 7b is preferably a carbon layer, a graphene layer, or a silver layer formed by applying a conductive paste such as carbon paste, graphene paste, or silver paste. Further, the conductive layer 7b may be a composite layer in which a silver layer is provided on a carbon layer or a graphene layer, or a mixed layer in which carbon paste, graphene paste, and silver paste are mixed.

The conductive layer 7b can be formed by applying a conductive paste such as carbon paste onto the solid electrolyte layer 7a by sponge transfer, screen printing, spray coating, dispenser, inkjet printing, or the like. Note that it is preferable to laminate the cathode extraction layer 7c in the next step while the conductive layer 7b is in a viscous state before drying. The thickness of the conductive layer 7b is preferably 2 μm or more, and preferably 20 μm or less.

A conductive adhesive layer may be provided on the conductive layer 7b. Examples of the material constituting the conductive adhesive layer include a mixture of an insulating resin such as an epoxy resin or a phenol resin, and conductive particles such as carbon or silver.

The cathode extraction layer 7c can be formed of metal foil or a printed electrode layer.

When the cathode extraction layer 7c is made of metal foil, the metal foil is made of at least one kind selected from the group consisting of aluminum, nickel, copper, silver, alloys containing these metals as main components, and stainless steel (SUS). Preferably, it is made of metal. When the metal foil is made of the above metals, the resistance value of the metal foil can be reduced and the ESR can be reduced. Further, as the metal foil, a metal foil whose surface is coated with carbon or titanium by a film forming method such as sputtering or vapor deposition may be used. It is more preferable to use carbon-coated aluminum foil.

The thickness of the metal foil is not particularly limited, but from the viewpoint of handling in the manufacturing process, miniaturization, and reducing ESR, it is preferably 20 μm or more, and preferably 50 μm or less.

It is preferable that a roughened surface is formed on the surface of the metal foil. When a roughened surface is formed on the surface of the metal foil, the adhesion between the cathode extraction layer 7c and the conductive layer 7b is improved, so that ESR can be reduced. The method for forming the roughened surface is not particularly limited, and the roughened surface may be formed by etching or the like. In particular, when aluminum foil is used, it is preferable to apply carbon coating or titanium coating to the aluminum foil that has been subjected to surface roughening treatment such as etching in order to lower the resistance.

Further, a coating layer made of an anchor coating agent may be formed on the surface of the metal foil. When a coating layer made of an anchor coating agent is formed on the surface of the metal foil, the adhesion between the cathode extraction layer 7c and the conductive layer 7b is improved, so that ESR can be reduced.

When the cathode extraction layer 7c is composed of a printed electrode layer, the cathode extraction layer 7c is formed in a predetermined area by applying electrode paste onto the conductive layer 7b by sponge transfer, screen printing, spray coating, dispenser, inkjet printing, etc. can do. As the electrode paste, an electrode paste containing nickel, silver or copper as a main component is preferable. When the cathode extraction layer 7c is a printed electrode layer, it is possible to make the cathode extraction layer 7c thinner than when using metal foil. For example, in the case of screen printing, the thickness may be 2 μm or more and 20 μm or less.

The thickness of the cathode extraction layer 7c described above is the thickness of the inside of the cathode extraction layer 7c excluding the portion exposed from the end face.

The sealing resin 8 constituting the resin molded body 9 contains at least a resin, and preferably contains a resin and a filler. Examples of the resin contained in the sealing resin 8 include epoxy resin, phenol resin, polyimide resin, silicone resin, polyamide resin, and liquid crystal polymer. As for the form of the resin, both solid resin and liquid resin can be used. Furthermore, examples of fillers included in the sealing resin 8 include silica particles, alumina particles, metal particles, and the like. As the sealing resin 8, it is more preferable to use a material containing silica particles in solid epoxy resin and phenol resin.

When the sealing resin 8 contains a resin and a filler, from the viewpoint of ensuring the fillability of the sealing resin 8, the maximum diameter of the filler is preferably smaller than the minimum thickness of the cathode extraction layer 7c. The maximum filler diameter is preferably in a range of, for example, 30 μm or more and 40 μm or less.

As a method for molding the resin molded body 9, when a solid sealing material is used, it is preferable to use a resin mold such as a compression mold or a transfer mold, and it is more preferable to use a compression mold. Moreover, when using a liquid sealant, it is preferable to use a molding method such as a dispensing method or a printing method. It is preferable to seal the laminate 30 of the capacitor elements 20 with the sealing resin 8 using a compression mold to form the resin molded body 9.

As in the example shown in FIG. 2, it is preferable that a support substrate 9g is provided at the bottom of the resin molded body 9. The support substrate 9g is preferably made of an insulating material. Examples of the insulating material constituting the support substrate 9g include glass epoxy resin, glass composite, phenol resin, polyimide resin, polyamide resin, fluororesin, polyphenylene oxide (PPO) resin, and bismaleimide triazine (BT) resin. .

Preferably, the corners of the resin molded body 9 are rounded by barrel polishing after resin molding. The corner portion is a portion where three surfaces of the resin molded body 9 intersect. Since resin molded bodies are softer than ceramic bodies, it is difficult to form rounded corners by barrel polishing, but the radius of curvature can be reduced by adjusting the media composition, particle size, shape, barrel processing time, etc. It is possible to form a rounded shape.

The first external electrode 11 and the second external electrode 13 can be formed by, for example, plating, sputtering, dip coating, printing, or the like. As the plating layer, Zn/Ag/Ni layer, Ag/Ni layer, Ni layer, Zn/Ni/Au layer, Ni/Au layer, Zn/Ni/Cu layer, Ni/Cu layer, etc. can be used. . It is preferable to further form a plating layer on these plating layers, for example, in the order of a Cu plating layer, a Ni plating layer, and a Sn plating layer (or excluding some of them).

[Method for manufacturing solid electrolytic capacitors]
The solid electrolytic capacitor of the present invention can be manufactured, for example, by the following method.

(Preparation of capacitor element)
First, a valve metal base such as aluminum foil having a porous portion such as an etching layer on the surface of the core is prepared, and the surface of the porous portion is anodized to form a dielectric layer. Next, a solid electrolyte layer is formed on the dielectric layer by screen printing, then a carbon layer that becomes a conductive layer is formed on the solid electrolyte layer by screen printing, and then an electrode extension layer is laminated as a sheet on the carbon layer. Or formed by screen printing. Through the above steps, a capacitor element is obtained.

(Preparation of resin molded body)
After laminating a plurality of capacitor elements, they are pressed together using a thermocompression press or the like to produce a laminate. It is preferable to stack the capacitor elements on a support substrate. Thereafter, the laminate is sealed with a sealing resin using a compression mold or the like. Through the above steps, a resin molded body is obtained.

For example, the thickness or coating area of at least one cathode (for example, the thickness or coating area of a carbon layer) of at least one of the capacitor elements adjacent in the stacking direction may be changed, or the pressure during crimping or sealing may be changed to a non-contact area. It is possible to form a non-contact area of the cathode by weakening the area near the area. Alternatively, it is also possible to form the cathode non-contact area by applying paraffin wax to the area that will become the non-contact area and then heating it to scatter the wax.

Further, by sandwiching an insulating film or the like between the capacitor elements in advance, it is possible to fill at least a portion of the non-contact area with the insulating material.

Note that the resin molded body may be produced by the production method described in JP-A-2019-79866. The method for manufacturing the resin molded body includes a step of preparing a first sheet, a step of preparing a second sheet, a step of covering the first sheet with an insulating material, and a step of coating a solid electrolyte layer of the first sheet with a conductive material. A process of forming a body layer, a process of laminating a first sheet and a second sheet to produce a laminated sheet, a process of sealing with a sealing resin to produce a laminated block body, and cutting the laminated block body. This includes the step of producing a plurality of resin molded bodies.

The first sheet is a sheet comprising a valve metal base on which a dielectric layer is formed and a solid electrolyte layer provided on the dielectric layer, and the second sheet is a sheet made of metal foil. It is. The first sheet and the second sheet each have a through hole in a portion that becomes the first end surface or the second end surface of the resin molded body, and the through holes are made to communicate when forming a laminated sheet. . Then, when sealing with the sealing resin, the through holes are filled with the sealing resin to produce a laminated block body. A resin molded body can be obtained by cutting this laminated block body so as to separate the sealing resin sealed in the through hole. In this resin molded body, the valve metal base is divided into a plurality of anode parts and exposed by the sealing resin sealed in the through hole. Furthermore, the cathode extraction layer is also exposed in a plurality of cathode parts by the sealing resin sealed in the through hole.

(Formation of external electrode)
A first external electrode is formed on a first end surface of the resin molded body, and a second external electrode is formed on a second end surface of the resin molded body. Through the above steps, the solid electrolytic capacitor of the present invention is obtained.

The solid electrolytic capacitor of the present invention is not limited to the above-described embodiments, and various applications and modifications can be made within the scope of the present invention regarding the structure, manufacturing conditions, etc. of the solid electrolytic capacitor.

1, 1A Solid electrolytic capacitor 3 Anode 3a Valve metal base 5 Dielectric layer 7 Cathode 7a Solid electrolyte layer 7b Conductive layer 7c Cathode extraction layer 8 Sealing resin 9 Resin molded body 9a First end surface 9b Second end surface 9c Bottom surface 9d Top surface 9e First side surface 9f Second side surface 9g Support substrate 11 First external electrode 13 Second external electrodes 20, 20A, 20B, 20C, 20D, 20E, 20F, 20G, 20H Capacitor element 30 Laminated body 41 Non-contact area 42 Contact area 43 Insulating material

Claims (3)

A laminate in which a plurality of capacitor elements are stacked, a sealing resin that seals the periphery of the laminate, and a bottom surface and a top surface facing each other in a thickness direction parallel to the stacking direction of the capacitor elements; a resin molded body having a first end face and a second end face facing each other in a length direction perpendicular to the direction, and a first side face and a second side face facing each other in a width direction perpendicular to the lamination direction and the length direction;
a first external electrode provided on the first end surface of the resin molded body;
a second external electrode provided on the second end surface of the resin molded body;
A solid electrolytic capacitor comprising:
The capacitor element includes an anode having a dielectric layer on its surface, and a cathode facing the anode with the dielectric layer interposed therebetween,
The anode includes a valve metal base having a porous portion on the surface of the core,
The cathode includes a cathode extraction layer,
the first external electrode is electrically connected to the valve metal base exposed from the first end surface;
the second external electrode is electrically connected to the cathode extraction layer exposed from the second end surface;
Between at least one set of capacitor elements adjacent in the stacking direction, there is a non-contact area where the cathode of one capacitor element and the cathode of the other capacitor element do not come into contact; a contact area where the cathode of the capacitor element contacts the cathode of the other capacitor element ;
A solid electrolytic capacitor , wherein at least a portion of the non-contact area is filled with an insulating material . The solid electrolytic capacitor according to claim 1, wherein the non-contact area is located at the center of the resin molded body in the length direction and width direction. 3. The solid electrolytic capacitor according to claim 1, wherein the non-contact area is located between a pair of capacitor elements closest to the center in the thickness direction of the resin molded body.

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