Electrolytic capacitors

Abstract

The disclosed electrolytic capacitor (100) includes a capacitor element (110) and a cathode lead terminal (130). The capacitor element (110) includes an anode body (113) and a cathode portion (115). The cathode lead terminal (130) includes a connecting portion (133) connected to the cathode portion (115) via a conductive member (141). The connecting portion (133) includes a plate-like portion (133a) and first and second side walls rising from the plate-like portion (133a). A plurality of grooves (133g) are formed on the surface of the plate-like portion (133a) and the first and second side walls. The plurality of grooves (133g) include a plurality of first and second grooves formed to be connected from the plate-like portion (133a) to the first and second side walls. The conductive member (141) is arranged between one surface of the cathode portion (115) and the plate-shaped portion (133a), and between two side surfaces of the cathode portion (115) and the first and second side surfaces.

Description

Technical Field

[0001] The present disclosure relates to electrolytic capacitors. Background Art

[0002] Electrolytic capacitors are installed in various electronic devices. Electrolytic capacitors generally include: a capacitor element having an anode portion and a cathode portion, an anode lead terminal, a cathode lead terminal, and an outer resin covering the capacitor element. The anode lead terminal is electrically connected to the anode portion, and the cathode lead terminal is electrically connected to the cathode portion.

[0003] In the past, cathode lead terminals of various shapes have been proposed (for example, Patent Documents 1 to 3). Patent Document 1 discloses "an electrolytic capacitor characterized in that a concave portion including a plurality of grooves or recesses is provided on the surface of the cathode lead frame that contacts the conductive adhesive and the surface that contacts the exterior resin."

[0004] In Patent Document 2 Figure 7 , it is disclosed that both sides of a cathode lead terminal are bent upward to form an embedded portion.

[0005] Prior Art Literature

[0006] Patent Literature

[0007] Patent Document 1: Japanese Patent Application Publication No. 2006-237195

[0008] Patent Document 2: Japanese Patent Application Publication No. 2003-068576

[0009] Patent Document 3: Japanese Patent Application Publication No. 2009-141208 Summary of the invention

[0010] -Problems to be solved by the invention-

[0011] In an electrolytic capacitor, it is necessary to reduce ESR and the like. Under such circumstances, one object of the present disclosure is to provide an electrolytic capacitor having a low ESR.

[0012] -Methods for solving the problem-

[0013] One aspect of the present disclosure relates to an electrolytic capacitor. The electrolytic capacitor includes: a capacitor element, an anode lead terminal and a cathode lead terminal electrically connected to the capacitor element, a conductive member, and an outer resin arranged around the capacitor element, the capacitor element including: an anode body as a porous sintered body with a dielectric layer formed on the surface, an anode wire protruding from the end surface of the anode body, and a cathode portion arranged adjacent to the dielectric layer, the cathode portion having: a first and a second side surface, and a bottom surface and an upper surface connecting the first and the second side surfaces, the cathode lead terminal including a connecting portion connected to the cathode portion via the conductive member, the connecting portion including: a plate-shaped portion sandwiching the conductive member. A conductive member is disposed between the one surface and the plate-shaped portion, between the first side surface and the first side wall, and between the second side wall and the second side wall.

[0014] Another aspect of the present disclosure relates to another electrolytic capacitor. The other electrolytic capacitor includes: a capacitor element, an anode lead terminal and a cathode lead terminal electrically connected to the capacitor element, a conductive member, and an outer resin arranged around the capacitor element, wherein the capacitor element includes: an anode body which is a porous sintered body having a dielectric layer formed on the surface, an anode wire protruding from an end surface of the anode body, and a cathode portion arranged to surround the anode body, the cathode portion having: two side surfaces, and a bottom surface and an upper surface connecting the two side surfaces, the cathode lead terminal includes a connection portion connected to the cathode portion via the conductive member, the connection portion includes: a plate-shaped portion facing any one of the bottom surface and the upper surface with the conductive member sandwiched therebetween; and two side walls rising from the plate-shaped portion and facing the two side surfaces, respectively, the conductive member is arranged between the one surface and the plate-shaped portion, and between the two side surfaces and the two side walls facing the two side surfaces, and the volume between the cathode portion and the two side walls increases as the distance from the end surface increases.

[0015] Another aspect of the present disclosure relates to another electrolytic capacitor. The other electrolytic capacitor includes: a capacitor element, an anode lead terminal and a cathode lead terminal electrically connected to the capacitor element, a conductive member, and an outer resin arranged around the capacitor element, wherein the capacitor element includes: an anode body as a porous sintered body with a dielectric layer formed on the surface, an anode wire protruding from the end surface of the anode body, and a cathode portion arranged to surround the anode body, wherein the cathode portion has: two side surfaces, and a bottom surface and an upper surface connecting the two side surfaces, and the cathode lead terminal includes a conductive member and an outer resin arranged around the capacitor element. The connecting portion is connected to the cathode portion through the conductive component, and the connecting portion includes: a plate-like portion, which clamps the conductive component and is opposite to any one of the bottom surface and the upper surface; and two side walls, which stand up from the plate-like portion and are respectively opposite to the two side surfaces, the conductive component is arranged between the one surface and the plate-like portion, and between the two side surfaces and the two side walls opposite to the two side surfaces, and the end portions of the two side walls on the end surface side are farther away from the end surface than the end portions of the plate-like portion on the end surface side.

[0016] -Effects of the Invention-

[0017] According to the present disclosure, an electrolytic capacitor with low ESR can be obtained.

[0018] The novel features of the present invention are described in the claims, but both the structure and content of the present invention, as well as other objects and features of the present invention will be more easily understood through the following detailed description with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a cross-sectional view schematically showing an example of the first electrolytic capacitor of the present disclosure.

[0020] Figure 2 It is schematically indicated Figure 1 A cross-section view of line II-II.

[0021] Figure 3A It is schematically indicated Figure 1 An expanded view of a portion of the cathode lead terminal of an electrolytic capacitor is shown.

[0022] Figure 3B It is schematically indicated Figure 1 A side view of the cathode lead terminal of an electrolytic capacitor is shown.

[0023] Figure 4 This is a development view schematically showing a part of another example of the cathode lead terminal.

[0024] Figure 5This is a development view schematically showing a part of another example of the cathode lead terminal.

[0025] Figure 6 This is a development view schematically showing a part of another example of the cathode lead terminal.

[0026] Figure 7 It is a cross-sectional view schematically showing another example of the first electrolytic capacitor of the present disclosure.

[0027] Figure 8 It is a cross-sectional view schematically showing another example of the first electrolytic capacitor of the present disclosure.

[0028] Fig. 9 It is a cross-sectional view schematically showing an example of the second electrolytic capacitor of the present disclosure.

[0029] Fig.10 It is schematically indicated Fig. 9 A cross-section diagram at line XX.

[0030] Fig.11A It is schematically indicated Fig. 9 An expanded view of a portion of the cathode lead terminal of an electrolytic capacitor is shown.

[0031] Fig. 11B It is schematically indicated Fig. 9 A top view of the cathode lead terminal of an electrolytic capacitor is shown.

[0032] Fig. 11C It is schematically indicated Fig. 9 A side view of the cathode lead terminal of an electrolytic capacitor is shown.

[0033] Fig.12 It is a cross-sectional view schematically showing another example of the second electrolytic capacitor of the present disclosure.

[0034] Fig.13A It is schematically indicated Fig.12 An expanded view of a portion of the cathode lead terminal of an electrolytic capacitor is shown.

[0035] Fig. 13B It is schematically indicated Fig.12 A top view of a portion of a cathode lead terminal of an electrolytic capacitor is shown.

[0036] Fig.14 It is a cross-sectional view schematically showing an example of a third electrolytic capacitor of the present disclosure.

[0037] Fig.15 It is schematically indicated Fig.14 A diagram of a cross section at line XV-XV.

[0038] Fig.16A It is schematically indicated Fig.14 An expanded view of a portion of the cathode lead terminal of an electrolytic capacitor is shown.

[0039] Fig. 16B It is schematically indicated Fig.14 A top view of a portion of a cathode lead terminal of an electrolytic capacitor is shown.

[0040] Fig. 16C It is schematically indicated Fig.14 A side view of a portion of the cathode lead terminal of an electrolytic capacitor is shown. DETAILED DESCRIPTION

[0041] Hereinafter, embodiments of the first to third electrolytic capacitors involved in the present disclosure will be described with examples. However, the electrolytic capacitors involved in the present disclosure are not limited to the examples described below. In the following description, specific numerical values ​​and materials may be exemplified, but other numerical values ​​and materials may also be applied as long as the effects of the present disclosure can be obtained. In addition, for structural elements other than the characteristic parts of the present disclosure, structural elements of known electrolytic capacitors may also be applied. In this specification, in the case of "a range of numerical values ​​A to numerical values ​​B", numerical values ​​A and numerical values ​​B are included in the range.

[0042] (1st electrolytic capacitor)

[0043] The first electrolytic capacitor disclosed in the present invention includes: a capacitor element, an anode lead terminal and a cathode lead terminal electrically connected to the capacitor element, a conductive member, and an outer resin arranged around the capacitor element. The capacitor element includes: an anode body as a porous sintered body with a dielectric layer formed on the surface, an anode wire protruding from the end surface of the anode body, and a cathode part arranged adjacent to the dielectric layer. The cathode part has: a first and a second side surface, a bottom surface connecting the first and the second side surfaces, and an upper surface. The cathode lead terminal includes a connecting part connected to the cathode part via a conductive member. The connecting part includes: a plate-like part that faces any one of the bottom surface and the upper surface by sandwiching the conductive member, and a first and a second side wall that stands up from the plate-like part, that is, the first and the second side walls that face the first and the second side surfaces, respectively. A plurality of grooves are formed on the surface of the cathode part side among the surfaces of the plate-like part and the first and the second side walls. The plurality of grooves include: a plurality of first grooves formed to be connected from the plate-shaped portion to the first side wall, and a plurality of second grooves formed to be connected from the plate-shaped portion to the second side wall. The conductive member is disposed between the one surface and the plate-shaped portion, between the first side surface and the first side wall, and between the second side surface and the second side wall. That is, the conductive member contacts and connects the one surface and the plate-shaped portion, contacts and connects the first side surface and the first side wall, and contacts and connects the second side surface and the second side wall.

[0044] The anode lead terminal and the cathode lead terminal may also include an anode terminal portion and a cathode terminal portion respectively exposed on the surface of the electrolytic capacitor. When the electrolytic capacitor is mounted, these anode terminal portions and cathode terminal portions are bonded to a substrate or the like by solder or the like. In this specification, the side where the anode terminal portion and the cathode terminal portion are exposed is sometimes referred to as the bottom side, and the side opposite to the bottom side is referred to as the top side.

[0045] The anode body is, for example, in the shape of a rectangular parallelepiped, and has: a bottom surface on the side of the anode terminal portion and the cathode terminal portion, an upper surface opposite to the bottom surface, an end surface (E) from which the anode lead terminal protrudes, a first and a second side surface, and a surface opposite to the end surface (E). The first and the second side surfaces are connected to the end surface (E), the bottom surface, and the upper surface. The first and the second side surfaces of the cathode portion are surfaces on the outer side of the cathode portion formed on the first and the second side surfaces of the anode body. The bottom surface of the cathode portion is a surface on the outer side of the cathode portion formed on the bottom surface of the anode body. The upper surface of the cathode portion is a surface on the outer side of the cathode portion formed on the upper surface of the anode body.

[0046] The cathode portion is formed to surround the anode body with the dielectric layer interposed therebetween. The cathode portion may be formed with the dielectric layer interposed therebetween on five surfaces of the anode body except the end surface (E) where the anode lead protrudes. In this case, the cathode portion is formed in a square tube shape with one end closed.

[0047] In order to reduce ESR, it is necessary to expand the connection area between the cathode portion and the cathode lead terminal. In the case of the electrolytic capacitor of Patent Document 1, in order to expand the connection area between the cathode portion and the cathode lead terminal, it is considered to apply a conductive adhesive to the entire surface of the cathode lead terminal opposite to the cathode portion. However, in this case, there is a concern that the applied conductive adhesive will extend from between the cathode portion and the cathode lead terminal, causing problems in the covering based on the outer resin, or causing problems such as short circuits. In addition, in the electrolytic capacitor of Patent Document 1, when the cathode portion of the capacitor element is connected to the cathode lead terminal, it may be difficult to maintain the capacitor element in a stable position.

[0048] On the other hand, the connection portion of the first electrolytic capacitor includes a plate-like portion and first and second side walls. Therefore, even when a large amount of conductive material (a material that becomes a conductive member, such as a metal paste) is arranged between the plate-like portion and the cathode portion in order to expand the connection area between the plate-like portion and the cathode portion, the excess conductive material moves between the first and second side walls of the connection portion and the cathode portion, and can be suppressed from extending from the connection portion. In addition, with this structure, the plate-like portion and the first and second side walls of the connection portion are connected to the cathode portion through the conductive member. Therefore, the connection area between the plate-like portion and the cathode portion can be expanded, and the ESR can be reduced.

[0049] In particular, a groove is formed in the connection portion of the first electrolytic capacitor, which is connected to the plate-like portion and the first and second side walls. Through the groove, the conductive material arranged on the surface of the plate-like portion and / or the surface of the cathode portion can easily move between the first and second side walls and the plate-like portion. Therefore, it is particularly easy to expand the connection area between the plate-like portion and the cathode portion through the first electrolytic capacitor. Furthermore, by forming a groove in the connection portion, the anchoring effect can be improved, and the bonding force between the connection portion and the cathode portion can be improved. That is, through this structure, a highly reliable electrolytic capacitor is obtained.

[0050] Furthermore, in the first electrolytic capacitor, when the capacitor element is connected to the cathode lead terminal, the movement of the capacitor element is restricted by the first and second side walls of the cathode lead terminal. Therefore, the capacitor element can be easily positioned, and the capacitor element can be prevented from being displaced and connected to the cathode lead terminal. Therefore, the present disclosure can provide an electrolytic capacitor that is easy to manufacture and has high reliability.

[0051] The width, depth, number, and area of ​​the grooves formed in the connection portion of the cathode lead terminal are not particularly limited. The number of grooves formed is also not particularly limited.

[0052] Hereinafter, the direction in which the anode wire extends may be referred to as "direction D1". The end of the connection portion (the end on the end face (E) side) may be present on the end face (E) side more than the center (center in direction D1) of the anode body. With this structure, the area of ​​the connection portion connected to the cathode portion through the conductive member can be increased.

[0053] The plate-shaped portion, the first side wall, and the second side wall of the connection portion may each be in a rectangular shape, or may be in a shape other than a rectangular shape.

[0054] The conductive member may be arranged in the first groove so as to extend from the plate-like portion to the first side wall, and the conductive member may be arranged in the second groove so as to extend from the plate-like portion to the second side wall. With this structure, a particularly high anchoring effect can be obtained.

[0055] The plurality of first grooves may be connected to corresponding grooves among the plurality of second grooves to form one groove. That is, the plurality of grooves may be connected from the plate-like portion to the first and second side walls.

[0056] The plurality of grooves may extend in directions substantially perpendicular to the direction in which the anode wires extend. With this structure, the conductive material disposed on the surface of the plate-like portion and / or the cathode portion opposite to the plate-like portion can easily move between the first and second side walls and the plate-like portion. Here, the substantially perpendicular direction refers to a direction with an inclination of less than 10° relative to the perpendicular direction.

[0057] In addition, as long as each groove is formed to be connected from the connecting portion to the side wall portion, the configuration of the plurality of grooves may be a configuration other than the above configuration. For example, the plurality of grooves may also be crossed in a lattice shape. In this case, each groove is also connected from the connecting portion to the side wall portion. The plurality of grooves may be straight lines, curves, or a combination of a plurality of straight lines and / or curves.

[0058] The grooves formed in the first and second side walls among the plurality of grooves may also be formed so as to be further away from the end surface (E) as they are further away from the plate-like portion. With this structure, it is easy to guide the material of the conductive member disposed between the side wall and the cathode portion to a position away from the end surface (E). As a result, it is easy to prevent a short circuit between the anode portion and the cathode portion.

[0059] A groove may also be formed on the surface of the plate-shaped portion of the connecting portion and the first and second side walls on the side opposite to the surface on the cathode side. Furthermore, an external resin may be arranged in the groove on the surface on the opposite side. With this structure, the bonding strength between the external resin and the connecting portion can be improved by the anchoring effect.

[0060] The first and second side walls of the connecting portion may also be substantially parallel to the first and second side surfaces of the anode body. That is, the first and second side walls of the connecting portion may also stand up substantially vertically from the plate-like portion. For example, the angle formed by the plate-like portion and the first side wall, and the angle formed by the plate-like portion and the second side wall may also be greater than 90° and less than 100°. Alternatively, the first and second side walls of the connecting portion may also be formed to separate from each other as they move away from the plate-like portion. For example, the angle formed by the plate-like portion and the first side wall, and the angle formed by the plate-like portion and the second side wall may also be greater than 100° and less than 120°. With this structure, even when the amount of conductive material as the material of the conductive component is large, it is possible to suppress the conductive material from protruding from the second side wall.

[0061] (Second electrolytic capacitor)

[0062] The second electrolytic capacitor includes: a capacitor element, an anode lead terminal and a cathode lead terminal electrically connected to the capacitor element, a conductive member, and an outer resin arranged around the capacitor element. The capacitor element includes: an anode body as a porous sintered body with a dielectric layer formed on the surface, an anode wire protruding from the end face of the anode body, and a cathode part arranged to surround the anode body. The cathode part has: two side faces, a bottom face connecting the two side faces, and an upper face. The cathode lead terminal includes a connecting part connected to the cathode part via a conductive member. The connecting part includes: a plate-shaped part that faces any one of the bottom face and the upper face of the cathode part by sandwiching the conductive member, and two side walls that stand up from the plate-shaped part, that is, two side walls that face the two side faces of the cathode part respectively. The conductive member is arranged between the above-mentioned one face and the plate-shaped part of the connecting part, and between the two side faces of the cathode part and the two side walls of the connecting part facing the two side faces. The volume between the cathode part and the two side walls increases as it moves away from the above-mentioned end face of the anode body. Hereinafter, the end surface of the anode body from which the anode wire protrudes may be referred to as “end surface (E)”.

[0063] In the second and third capacitors, the two side surfaces of the cathode portion can be replaced by the first side surface and the second side surface, and the two side walls of the connection portion can be replaced by the first side wall and the second side wall. The first side surface and the second side surface of the cathode portion are respectively opposite to the first side wall and the second side wall of the connection portion.

[0064] The cathode portion and the cathode lead terminal are connected via a conductive member. The conductive member can be formed by, for example, applying a conductive material to the cathode portion and / or the plate-like portion of the cathode lead terminal and then converting the conductive material into the conductive member by heating or the like.

[0065] In order to reduce ESR, it is necessary to increase the connection area of ​​the connection portion between the cathode portion and the cathode lead terminal. To this end, it is necessary to increase the area of ​​the conductive member, and it is considered to apply a conductive material to a wide range of the surface of the connection portion. However, if a large amount of conductive material is applied to increase the area of ​​the conductive member, the possibility of excess conductive material protruding from the plate-like portion and causing a short circuit between the anode wire and the cathode portion increases.

[0066] In the above-mentioned second electrolytic capacitor, the connecting portion of the cathode lead terminal has a side wall. Therefore, the side wall and the cathode portion can also be connected by a conductive member. As a result, a lower ESR can be achieved. In addition, in the second electrolytic capacitor, the volume between the cathode portion and the two side walls increases as the end face (E) away from the anode body. Therefore, even if a large amount of conductive material is applied, the excess conductive material is guided in the direction away from the end face (E) where the anode line exists. Therefore, it is possible to prevent the protruding conductive material from reaching the end face (E), and it is possible to prevent undesirable situations such as a short circuit between the anode portion and the cathode portion. That is, the second electrolytic capacitor can be manufactured with a good yield. In addition, through this structure, a large amount of conductive adhesive can be applied, so the area of ​​the conductive member can be increased. As a result, the ESR can be reduced.

[0067] The width of the plate-like portion of the connection portion of the cathode lead terminal may also be increased as it moves away from the end surface (E), at least in the portion connected to the two side walls. In this case, the angle α1 formed by the direction in which the side wall of the connection portion extends and the side surface of the cathode portion (more specifically, the surface including the side surface) may also be in the range of 5 to 20°.

[0068] Alternatively, the plate-like portion of the connection portion of the cathode lead terminal may also be rectangular in shape. Furthermore, the distance between the two side walls of the connection portion and the cathode portion may also increase as the distance from the end face (E) and the distance from the plate-like portion increase. In this case, the angle α2 formed by the direction in which the upper side of the side wall of the connection portion extends and the side surface of the cathode portion (more specifically, the surface including the side surface) may also be in the range of 5 to 20°. Here, the upper side refers to the side of the side wall that is farthest from the plate-like portion of the connection portion.

[0069] The distance between the end of the end face (E) side of the plate-like portion and the end face (E), i.e., the distance X1 in the direction D1 in which the anode wire 112 extends, and the distance between the end of the end face (E) side of the two side walls and the end face (E), i.e., the distance Y1 in the direction D1, may also be in the range of 10 to 40% (e.g., in the range of 20 to 30%) of the length L1 of the anode body in the direction D1. In addition, the distance X1 and the distance Y1 may be different, but are typically the same.

[0070] (No. 3 electrolytic capacitor)

[0071] The third electrolytic capacitor includes: a capacitor element, an anode lead terminal and a cathode lead terminal electrically connected to the capacitor element, a conductive member, and an outer resin arranged around the capacitor element. The capacitor element includes: an anode body as a porous sintered body with a dielectric layer formed on the surface, an anode wire protruding from the end face of the anode body, and a cathode part arranged to surround the anode body. The cathode part has: two side faces, a bottom face connecting the two side faces, and an upper face. The cathode lead terminal includes a connecting part connected to the cathode part via a conductive member. The connecting part includes: a plate-shaped part facing any one of the bottom face and the upper face with the conductive member sandwiched therebetween, and two side walls rising from the plate-shaped part, namely, two side walls facing the two side faces respectively. The conductive member is arranged between the above-mentioned one face and the plate-shaped part of the connecting part, and between the two side faces of the cathode part and the two side walls of the connecting part facing the two side faces. The end faces of the two side walls are further away from the end face than the end faces of the plate-shaped part.

[0072] The third electrolytic capacitor is different from the second electrolytic capacitor only in the shape of the connection portion of the cathode lead terminal, and therefore duplicate descriptions may be omitted.

[0073] In the third electrolytic capacitor, the connection portion of the cathode lead terminal has a side wall. Therefore, the side wall and the cathode portion can also be connected by a conductive member. As a result, a lower ESR can be achieved. In addition, in the third electrolytic capacitor, the ends of the two side walls of the connection portion on the end face (E) side are farther away from the end face (E) side than the ends of the plate-like portion of the connection portion on the end face (E) side. Therefore, even when a large amount of conductive material (material of the conductive member) is applied and excess conductive material protrudes, it is easy to protrude from the end of the end face (E) side of the side wall. Therefore, it is possible to prevent the conductive adhesive from reaching the end face (E) and causing a short circuit, etc. That is, the third electrolytic capacitor can be manufactured with a good yield. In addition, through this structure, a large amount of conductive adhesive can be applied, so the area of ​​the conductive member can be increased. As a result, the ESR can be reduced.

[0074] The third electrolytic capacitor may also satisfy the following structure (1).

[0075] (1) The distance between the end of the plate-like portion of the connection portion of the cathode lead terminal on the end face (E) side and the end face (E), that is, the distance X2 in the direction D2 in which the anode wire extends, is in the range of 10 to 50% (for example, in the range of 30 to 45%) of the length L2 of the anode body in the direction D2.

[0076] The third electrolytic capacitor may also satisfy the above-mentioned structure (1) and the following structure (2).

[0077] (2) The distance between the end portions of the two side walls of the connecting portion on the end face (E) side and the end face (E), that is, the difference (Y2-X2) between the distance Y2 in the direction D2 and the above-mentioned distance X2 is in the range of 10 to 50% (for example, in the range of 30 to 45%) of the above-mentioned length L2.

[0078] The electrolytic capacitor involved in the present disclosure can satisfy at least one condition selected from the group consisting of the following conditions (J1), (J2) and (J3). For example, the first electrolytic capacitor can satisfy condition (J2) and / or (J3). The second capacitor can satisfy condition (J3). In the following (J1) to (J3), the so-called "one surface" refers to the surface between the bottom surface and the upper surface of the cathode portion, which is opposite to the plate-like portion with the conductive member sandwiched therebetween.

[0079] (J1) A plurality of grooves are formed on the surface of the cathode portion among the surfaces of the plate-like portion and the first and second side walls. The plurality of grooves include: a plurality of first grooves formed to extend from the plate-like portion to the first side wall and connected thereto, and a plurality of second grooves formed to extend from the plate-like portion to the second side wall and connected thereto. The conductive member is disposed between the one surface and the plate-like portion, between the first side surface and the first side wall, and between the second side surface and the second side wall.

[0080] (J2) The conductive member is disposed between the one surface and the plate-shaped portion, and between the two side surfaces (the first and second side surfaces) and the two side walls (the first and second side walls) facing the two side surfaces. The volume between the cathode portion and the two side walls increases as the distance from the end surface increases.

[0081] (J3) The conductive member is disposed between the one surface and the plate-shaped portion, and between the two side surfaces (the first and second side surfaces) and the two side walls (the first and second side walls) facing the two side surfaces. The end portions of the two side walls on the end surface side are further away from the end surface than the end portions of the plate-shaped portion on the end surface side.

[0082] Examples of components common to the first to third electrolytic capacitors of the present disclosure are described below.

[0083] (Cathode lead terminal)

[0084] The cathode lead terminal has the above-mentioned characteristics. A typical cathode lead terminal includes: a cathode terminal portion exposed on the bottom surface of the electrolytic capacitor, and a connecting portion connected to the cathode terminal portion. As described above, the connecting portion is connected to the cathode portion via a conductive member.

[0085] The material of the cathode lead terminal may be any material that can be used as the material of the cathode lead terminal of the electrolytic capacitor. For example, a known cathode lead terminal material used in an electrolytic capacitor may be used. The cathode lead terminal may be formed by processing a metal sheet (including a metal plate and a metal foil) made of a metal (copper, a copper alloy, etc.) using a known metal processing method.

[0086] (Anode lead terminal)

[0087] A typical anode lead terminal includes: an anode terminal portion exposed on the bottom surface of the electrolytic capacitor, and a wire connection portion connected to the anode terminal portion. The wire connection portion is connected to the anode wire. The material of the anode lead terminal can be a material that can be used as a material of the anode lead terminal of the electrolytic capacitor. For example, a known anode lead terminal material used in an electrolytic capacitor can be used. The anode lead terminal can be formed by processing a metal sheet (including a metal plate and a metal foil) composed of a metal (copper, a copper alloy, etc.) using a known metal processing method.

[0088] (Capacitor Components)

[0089] The capacitor element includes an anode portion and a cathode portion. The capacitor element is not particularly limited, and a capacitor element used in a known electrolytic capacitor or a capacitor element having a similar structure thereto can be used.

[0090] The anode portion includes an anode body and an anode wire. The anode body is a porous sintered body with a dielectric layer formed on the surface. The cathode portion includes an electrolyte layer and a cathode layer. The electrolyte layer is arranged between the dielectric layer formed on the surface of the anode body and the cathode layer. These structural elements are not particularly limited, and structural elements used in known electrolytic capacitors can be applied. Examples of these structural elements are described below.

[0091] (Anode)

[0092] The anode body is formed by sintering particles as a material. Examples of the above particles include particles of valve metals, particles of alloys containing valve metals, and particles of compounds containing valve metals. These particles can be used alone or in combination of two or more. As valve metals, titanium (Ti), tantalum (Ta), niobium (Nb), etc. are used.

[0093] The anode body can also be produced by the following method. First, a part of the anode wire is embedded in a powder (e.g., metal powder) as a material of the anode body, and the powder is pressed and formed into a columnar shape (e.g., a rectangular parallelepiped shape). Then, the powder is sintered to form the anode body. In this way, an anode body in which a part of the anode wire is embedded can be produced.

[0094] The dielectric layer formed on the surface of the anode body is not particularly limited and can be formed by a known method. For example, the dielectric layer can be formed by immersing the anode body in a chemical conversion solution to anodize the surface of the anode body. Alternatively, the dielectric layer can be formed by heating the anode body in an environment containing oxygen to oxidize the surface of the anode body.

[0095] (Anode wire)

[0096] The anode wire may be a wire made of metal. Examples of the material of the anode wire include the above-mentioned valve metal, copper, aluminum, aluminum alloy, etc. A portion of the anode wire is buried in the anode body, and the remaining portion protrudes from the end face (E) of the anode body. The anode wire has a rod-like shape. The front end of the anode wire protruding from the anode body may have a cross-sectional shape different from that of the other portions.

[0097] (Electrolyte layer)

[0098] The electrolyte layer is not particularly limited, and the electrolyte layer used in the known electrolytic capacitor (such as a solid electrolytic capacitor) can be applied. In addition, in this specification, the electrolyte layer can be replaced by a solid electrolyte layer, and the electrolytic capacitor can be replaced by a solid electrolytic capacitor. The electrolyte layer can be a laminate of two or more different electrolyte layers.

[0099] The electrolyte layer is configured to cover at least a portion of the dielectric layer. The electrolyte layer can be formed using a manganese compound or a conductive polymer. Examples of conductive polymers include polypyrrole, polythiophene, polyaniline, and derivatives thereof. These can be used alone or in combination. In addition, the conductive polymer can be a copolymer of two or more monomers. In addition, the so-called derivative of the conductive polymer refers to a polymer with a conductive polymer as a basic skeleton. For example, examples of derivatives of polythiophene include poly(3,4-ethylenedioxythiophene) and the like.

[0100] It is preferred to add a dopant to the conductive polymer. The dopant can be selected according to the conductive polymer, and a known dopant can be used. Examples of the dopant include naphthalenesulfonic acid, p-toluenesulfonic acid, polystyrenesulfonic acid, and salts thereof. An example electrolyte layer is formed using poly(3,4-ethylenedioxythiophene) (PEDOT) doped with polystyrenesulfonic acid (PSS).

[0101] The electrolyte layer containing the conductive polymer can be formed by polymerizing a raw material monomer on the dielectric layer, or by applying a liquid containing the conductive polymer (and a dopant as required) to the dielectric layer and then drying it.

[0102] (Cathode layer)

[0103] The cathode layer may be a conductive layer formed on the electrolyte layer, for example, a conductive layer formed to cover the electrolyte layer. The cathode layer may include: a carbon layer formed on the electrolyte layer, and a metal paste layer formed on the carbon layer. The carbon layer may be formed by a conductive carbon material such as graphite and a resin. The metal paste layer may be formed by metal particles (such as silver particles) and a resin, for example, by a known silver paste.

[0104] (Conductive member)

[0105] The cathode layer is connected to the connecting portion of the cathode lead terminal through a conductive member. That is, the cathode layer (cathode portion) is electrically connected to the cathode lead terminal. The conductive member includes a material having conductivity. The conductive member can be formed using a material including metal particles (e.g., silver particles) and a resin, for example, it can be formed using a known metal paste (e.g., silver paste). The conductive member can be formed by curing the metal paste (e.g., curing based on heating). In addition, the conductive member can include a plurality of conductive layers of different types.

[0106] (Exterior resin)

[0107] The outer coating resin is arranged around the capacitor element so that the capacitor element is not exposed on the surface of the electrolytic capacitor. Furthermore, the outer coating resin insulates the anode lead terminal from the cathode lead terminal. The outer coating resin can be applied to the known outer coating resin used in electrolytic capacitors. For example, the outer coating resin can be formed using an insulating resin material used in the sealing of the capacitor element. Examples of outer coating resins include epoxy resins, phenolic resins, silicone resins, melamine resins, urea resins, alkyd resins, polyurethanes, polyimides, and unsaturated polyesters. The outer coating resin may contain substances other than resins (inorganic fillers, etc.).

[0108] (Method for manufacturing electrolytic capacitor)

[0109] The manufacturing method of the first to third electrolytic capacitors disclosed in the present invention is not particularly limited, and for example, can be manufactured by the manufacturing method described below. An example of the manufacturing method of the first to third electrolytic capacitors disclosed in the present invention includes: a coating process of coating a conductive material (a material that becomes a conductive component) on the plate-like portion and / or the cathode portion of the connecting portion of the cathode lead terminal, a bonding process of bonding the connecting portion to the cathode portion via the conductive material, and a process of converting the conductive material into a conductive component. The conductive material can be converted into a conductive component by heating, curing, etc. When the connecting portion and the cathode portion are bonded via the conductive material, the conductive material extends between the side of the cathode portion and the side wall of the connecting portion. In the case where a groove is formed in the plate-like portion and the side wall of the connecting portion, the conductive material is arranged in the groove so as to be connected from the plate-like portion to the side wall. In addition, in the coating process, the conductive material can be coated on the plate-like portion and the side wall portion.

[0110] Hereinafter, examples of the electrolytic capacitor disclosed in the present invention will be described in detail with reference to the accompanying drawings. The above-mentioned structural elements can be applied to the structural elements of the electrolytic capacitor of the example described below. In addition, the structural elements of the electrolytic capacitor of the example described below can be changed based on the above-mentioned description. In addition, the matters described below can also be applied to the above-mentioned embodiment. In addition, in the embodiment described below, non-essential structural elements in the electrolytic capacitor of the present invention can also be omitted.

[0111] (Implementation Method 1)

[0112] In the first embodiment, an example of a first electrolytic capacitor is described. Figure 1 Schematically shows a cross-sectional view of the electrolytic capacitor 100 of Embodiment 1. Furthermore, Figure 2 Indicated in Figure 1 In addition, Figure 3A 2 shows an expanded view of the cathode lead terminal 130 when the connecting portion 133 is flattened. Figure 3A This is an expanded view of the connection portion 133 when viewed from the side where the groove 133g is formed (the same applies to the expanded views below). Figure 3B shows a side view of the cathode lead terminal 130. In addition, Figure 3B , the position of the cathode portion 115 and the like are also indicated.

[0113] The electrolytic capacitor 100 includes a capacitor element 110, an anode lead terminal 120, a cathode lead terminal 130, an outer resin 101, and a conductive member 141. The capacitor element 110 includes an anode portion 111, a dielectric layer 114, and a cathode portion 115. The anode portion 111 includes an anode wire 112 and an anode body 113. The anode body 113 is a rectangular porous sintered body, and the surface is covered with a dielectric layer 114. A portion of the anode wire 112 protrudes from an end surface 113e of the anode body 113, and the other portion of the anode wire 112 is buried in the anode body 113. The portion of the capacitor element 110 other than the anode wire 112 is rectangular.

[0114] The cathode portion 115 includes an electrolyte layer 116 arranged to cover the dielectric layer 114 (in another viewpoint, to cover the anode body 113), and a cathode layer 117 formed on the electrolyte layer 116. The cathode layer 117 includes, for example, a carbon layer formed on the electrolyte layer 116 and a metal particle layer formed on the carbon layer. The metal particle layer is, for example, a layer formed using a metal paste.

[0115] The anode lead terminal 120 includes an anode terminal portion 121 and a wire connection portion 122. The anode terminal portion 121 is exposed at the bottom surface 100b of the electrolytic capacitor 100. The wire connection portion 122 is connected to the anode terminal portion 121. The wire connection portion 122 is connected to the anode wire 112. That is, the anode lead terminal 120 is electrically connected to the anode portion 111 of the capacitor element 110. In addition, Figure 1 The anode lead terminal 120 shown is an example, and may have other shapes as long as it can function as the anode lead terminal 120 .

[0116] The cathode lead terminal 130 includes a cathode terminal portion 131, a connecting portion 132, and a connecting portion 133. The cathode terminal portion 131 is exposed at the bottom surface 100b of the electrolytic capacitor 100. The connecting portion 132 connects the cathode terminal portion 131 and the connecting portion 133. The anode lead terminal 120 and the cathode lead terminal 130 can each be formed by processing a single metal sheet using a known metal processing method.

[0117] Hereinafter, the surface of the electrolytic capacitor 100 opposite to the bottom surface 100b may be referred to as the upper surface 100t of the electrolytic capacitor 100. The bottom surface 100b is a surface where the anode terminal 121 and the cathode terminal 131 are exposed.

[0118] The cathode portion 115 has: first and second side surfaces 115sa and 115sb, a bottom surface 115b connecting the first side surface 115sa and the second side surface 115sb, and an upper surface 115t. The bottom surface 115b is a surface on the bottom surface 100b side. The upper surface 115t is a surface on the upper surface 100t side. The first and second side surfaces 115sa and 115sb are substantially perpendicular to the end surface 113e.

[0119] The connecting portion 133 includes a plate-shaped portion 133a that faces the upper surface 115t of the cathode portion 115 with the conductive member 141 interposed therebetween, and a first side wall 133sa and a second side wall 133sb that rise from the plate-shaped portion 133a. The first side wall 133sa and the second side wall 133sb face the first side surface 115sa and the second side surface 115sb of the cathode portion 115 with the conductive member 141 interposed therebetween, respectively. The first side wall 133sa and the second side wall 133sb rise substantially vertically from the plate-shaped portion 133a.

[0120] The conductive member 141 is disposed between the upper surface 115t and the plate-shaped portion 133a, between the first side surface 115sa and the first side wall 133sa, and between the second side surface 115sb and the second side wall 133sb. That is, the conductive member 141 contacts and electrically connects the upper surface 115t and the plate-shaped portion 133a, contacts and electrically connects the first side surface 115sa and the first side wall 133sa, and contacts and electrically connects the second side surface 115sb and the second side wall 133sb.

[0121] Reference Figure 3A A plurality of grooves 133g arranged in stripes are formed on the surface of the plate-like portion 133a, the side walls 133sa, and 133sb, which face the cathode portion 115. Each groove 133g extends from the plate-like portion 133a to the first side wall 133sa and the second side wall 133sb and is connected. Each groove 133g extends in a direction perpendicular to the direction D1 in which the anode line 112 extends.

[0122] In addition, if Figure 3A As shown, the plurality of grooves 133g can be considered to include a plurality of first grooves 133ga and a plurality of second grooves 133gb. That is, the plurality of first grooves 133ga can be considered to be connected to the corresponding grooves among the plurality of second grooves 133gb to form one groove 133g. This is true for all grooves 133g (for example, Figure 5 as well as Figure 6The same applies to the groove 133g shown in FIG. 1. The plurality of first grooves 133ga are formed to be connected from the plate-shaped portion 133a to the first side wall 133sa. The plurality of second grooves 133gb are formed to be connected from the plate-shaped portion 133a to the second side wall 133sb.

[0123] Figure 3B , the height 133h of the first and second side walls of the connection portion 133 and the height 115h of the side surface 115sa of the cathode portion 115 are shown. The height 133h may be within the above range. Figure 3B , the center 113c (the center in the direction D1) of the anode body 113 is shown. Figure 3B One end of the connecting portion 133 shown is located closer to the end surface 113 e than the center 113 c .

[0124] The conductive member 141 is disposed between the upper surface 115t of the cathode portion 115 and the plate-shaped portion 133a of the connecting portion 133, and between the side surfaces 115sa and 115sb of the cathode portion 115 and the side walls 133sa and 133sb of the connecting portion 133, and electrically and physically connects them. In addition, in the plurality of grooves 133g, the conductive member 141 is disposed so as to be connected from the groove 133g of the plate-shaped portion 133a to the groove 133g of the first side wall 133sa and the second side wall 133sb. Through these structures, the contact area between the cathode portion 115 and the conductive member 141 can be enlarged, and the ESR can be reduced. In addition, through these structures, the conductive member 141 can be suppressed from protruding from the connecting portion 133, so that the undesirable situation such as short circuit can be suppressed. Further, the cathode portion 115 and the connecting portion 133 (cathode lead terminal 130) can be fixed with a high bonding force.

[0125] exist Figure 1 to Figure 3B In the example shown, the cathode lead terminal 130 is shown in which a linear groove 133g is formed. However, the groove 133g formed in the cathode lead terminal 130 may have another shape. Figures 4 to 6 FIG. 2 shows an expanded view of the cathode lead terminal 130 when it is flattened. Figures 4 to 6 The cathode lead terminal 130 shown can also achieve the above-mentioned effect.

[0126] exist Figure 4 A plurality of grooves 133g are formed in the connection portion 133 of the cathode lead terminal 130. The plurality of grooves 133g include a plurality of first grooves 133ga and a plurality of second grooves 133gb. Figure 4 The cathode lead terminal 130 shown in the figure is different from the cathode lead terminal 130 shown in FIG. 3 in that the first groove 133ga and the second groove 133gb are not connected. Other aspects are the same as the cathode lead terminal 130 shown in FIG. 3, so repeated description is omitted. Figure 4In the cathode lead terminal 130 shown, when forming the conductive member 141, the material of the conductive member 141 disposed in the portion where the groove 133g does not exist is easily moved to the groove 133g and the side walls 133sa and 133sb.

[0127] exist Figure 5 A plurality of grooves 133g are formed in the connection portion 133 of the cathode lead terminal 130. Figure 4 In the example shown, the groove 133g formed in the plate-like portion 133a is a linear groove extending substantially perpendicularly to the direction D1 in which the anode wire 112 extends. The grooves 133g formed in the side walls 133sa and 133sb are also linear grooves, but are formed so as to be farther away from the end surface 113e of the anode body 113 as they are farther away from the plate-like portion 133a. All the grooves 133g are connected from the plate-like portion 133a to the side walls 133sa and 133sb.

[0128] pass Figure 5 The structure can easily guide the material of the conductive member 141 disposed between the side surfaces 115sa and 115sb and the side walls 133sa and 133sb of the cathode portion 115 in a direction away from the end surface 113e. Thus, the material of the conductive member can be suppressed from extending toward the anode line 112 protruding from the end surface 113e, thereby preventing short circuits and the like.

[0129] exist Figure 6 The connection portion 133 of the cathode lead terminal 130 is formed with a plurality of grooves 133g. The plurality of grooves 133g includes a plurality of grooves 133gc arranged in a stripe shape and a plurality of grooves 133gd arranged in a stripe shape. The plurality of grooves 133gc and the plurality of grooves 133gd are inclined relative to a direction perpendicular to the direction D1 in which the anode wire 112 extends.

[0130] The plurality of grooves 133gc and the plurality of grooves 133gd are arranged to intersect each other. The plurality of grooves 133gc and 133gd are connected from the plate-like portion 133a to the first side wall 133sa and the second side wall 133sb, respectively. However, a part of the grooves 133gc and a part of the grooves 133gd may be connected from the plate-like portion 133a to only the side wall of the first side wall 133sa and the second side wall 133sb.

[0131] Figure 2 , an example is shown in which the first side wall 133sa and the second side wall 133sb are substantially perpendicular to the plate-shaped portion 133a. However, the first side wall 133sa and the second side wall 133sb may be expanded as they are away from the plate-shaped portion 133a. Figure 7 2 is a cross-sectional view of an example of an electrolytic capacitor 100 including such a connection portion 133. Figure 7In the illustrated connection portion 133 , the angle formed by the first side wall 133 sa and the second side wall 133 sb and the plate-shaped portion 133 a may be greater than or equal to 100 degrees.

[0132] A groove 133 z may be formed on the surface of the connection portion 133 on the side opposite to the surface on the cathode portion 115 side. Figure 8 1 is a cross-sectional view of an example of an electrolytic capacitor 100 including a cathode lead terminal 130 having a groove 133z formed therein. Figure 8 In the electrolytic capacitor 100, the outer resin 101 is arranged in the groove 133z. As a result, a high anchoring effect can be obtained, and the connection portion 133 of the cathode lead terminal 130 can be firmly fixed. In addition, the shape and arrangement of the groove 133z are not particularly limited. The groove 133z can also have the same shape as the groove 133g described above.

[0133] In Embodiment 1, an example is described in which the plate-shaped portion 133a of the connection portion 133 faces the upper surface 115t of the cathode portion 115 with the conductive member 141 interposed therebetween. However, the plate-shaped portion 133a may be arranged to face the bottom surface 115b of the cathode portion 115 with the conductive member 141 interposed therebetween. In this case, the first side wall 133sa and the second side wall 133sb extend from the plate-shaped portion 133a toward the upper surface 100t.

[0134] An example of a method for manufacturing the electrolytic capacitor 100 is described below. First, the capacitor element 110, the anode lead terminal 120, and the cathode lead terminal 130 are prepared. The method for manufacturing the capacitor element 110 is not particularly limited, and the capacitor element 110 can be manufactured by a known method. The anode lead terminal 120 and the cathode lead terminal 130 can be formed by a known metal processing method.

[0135] Next, the anode wire 112 is connected to the anode lead terminal 120, and the cathode layer 117 is connected to the cathode lead terminal 130. The anode wire 112 and the anode lead terminal 120 can also be connected by, for example, welding the front end of the anode lead terminal 120 to the wire connection portion 122. The connection between the cathode layer 117 and the cathode lead terminal 130 can be performed, for example, by the following method. First, a conductive material (for example, a metal paste) that becomes the conductive member 141 is applied to the surface of the connection portion 133 (for example, the plate-shaped portion 133a) of the cathode lead terminal 130 and / or the cathode portion 115 (cathode layer 117) of the capacitor element 110. Usually, the conductive material is applied to either the plate-shaped portion 133a or the cathode portion 115. Next, after the connection portion 133 and the cathode portion 115 are bonded via the conductive material, the conductive material is cured to become the conductive member 141. In this way, cathode portion 115 and cathode lead terminal 130 can be connected via conductive member 141 .

[0136] Next, the capacitor element is sealed with an exterior resin 101. The sealing step can be performed by a known method. In this way, the electrolytic capacitor 100 can be manufactured. In addition, other electrolytic capacitors of the present disclosure can also be manufactured by the same manufacturing method.

[0137] (Implementation Method 2)

[0138] In the second embodiment, an example of the second electrolytic capacitor described above will be described. Fig. 9 Schematically shows a cross-sectional view of an electrolytic capacitor 200 according to Embodiment 2. Furthermore, Fig.10 Indicated in Fig. 9 Cross-sectional view at line XX. Fig.11A 2 is a development view of the cathode lead terminal 130 when the connection portion 133 is flattened. Fig. 11B as well as Fig. 11C 1 and 2 show a top view and a side view of the cathode lead terminal 130, respectively. Fig. 11B as well as Fig. 11C The position of the cathode portion 115 and the like are also shown.

[0139] The electrolytic capacitor 200 includes a capacitor element 110, an anode lead terminal 120, a cathode lead terminal 130, an outer resin 101, and a conductive member 141. The capacitor element 110 includes an anode portion 111, a dielectric layer 114, and a cathode portion 115. The anode portion 111 includes an anode body 113 and an anode wire 112. The anode body 113 is a rectangular parallelepiped porous sintered body, and a dielectric layer 114 is formed on the surface. A portion of the anode wire 112 protrudes from an end surface 113e of the anode body 113, and the other portion of the anode wire 112 is buried in the anode body 113.

[0140] Cathode portion 115 includes electrolyte layer 116 arranged to cover dielectric layer 114 (anode body 113), and cathode layer 117 formed on electrolyte layer 116. Cathode layer 117 includes, for example, a carbon layer formed on electrolyte layer 116 and a metal particle layer formed on the carbon layer. The metal particle layer is, for example, a layer formed using a metal paste.

[0141] Anode lead terminal 120 includes anode terminal portion 121 and wire connection portion 122. Anode terminal portion 121 is exposed at bottom surface 100b of electrolytic capacitor 200. Wire connection portion 122 is connected to anode terminal portion 121. Wire connection portion 122 is connected to anode wire 112. That is, anode lead terminal 120 is electrically connected to anode portion 111 of capacitor element 110. In addition, Fig. 9 The anode lead terminal 120 shown is an example, and may have other shapes as long as it can function as the anode lead terminal 120 .

[0142] The cathode lead terminal 130 includes a cathode terminal portion 131, a connecting portion 132, and a connecting portion 133. The cathode terminal portion 131 is exposed at the bottom surface 100b of the electrolytic capacitor 200. The connecting portion 132 connects the cathode terminal portion 131 and the connecting portion 133. The anode lead terminal 120 and the cathode lead terminal 130 can be formed by processing a single metal sheet using a known metal processing method.

[0143] Hereinafter, the surface of electrolytic capacitor 200 opposite to bottom surface 100b may be referred to as upper surface 100t of electrolytic capacitor 200. Bottom surface 100b is a surface where anode terminal 121 and cathode terminal 131 are exposed.

[0144] The cathode portion 115 has two side surfaces 115s, a bottom surface 115b connecting the two side surfaces 115s, and a top surface 115t. The bottom surface 115b is a surface on the bottom surface 100b side. The top surface 115t is a surface on the top surface 100t side. The two side surfaces 115s are substantially perpendicular to the end surface 113e.

[0145] The connection part 133 includes a plate-shaped part 133a facing the bottom surface 115b with the conductive member 141 sandwiched therebetween, and two side walls 133s rising from the plate-shaped part 133a. The two side walls 133s respectively face the two side surfaces 115s of the cathode part 115 with the conductive member 141 sandwiched therebetween. The two side walls 133s rise substantially vertically from the plate-shaped part 133a.

[0146] The conductive member 141 is disposed between the bottom surface 115b and the plate-shaped portion 133a, and between the two side surfaces 115s and the two side walls 133s facing the respective side surfaces. That is, the conductive member 141 contacts the bottom surface 115b and the plate-shaped portion 133a and electrically connects them. Furthermore, the conductive member 141 contacts the two side surfaces 115s and the two side walls 133s and electrically connects them.

[0147] Fig.11A denoted by . The width W of the plate-like portion 133 a is the length of the plate-like portion 133 a in a direction perpendicular to the direction D1 . The width W of the plate-like portion 133 a increases as it becomes farther away from the end surface 113 e of the anode body 113 . Fig.11A The plate-like portion 133a shown has an equilateral trapezoidal shape, and two side walls 133s stand from two legs of the equilateral trapezoidal shape. Fig.11A The side wall 133s is shown to be rectangular in shape.

[0148] Fig. 11B denoted in the figure is an angle α1 formed between the direction in which the side wall 133 s extends and the side surface 115 s of the cathode portion 115 (more specifically, the surface including the side surface 115 s ). Fig. 11C , represents the distance between the end (end side) 133ae of the plate-shaped portion 133a on the end face 113e side and the end face 113e, i.e., the distance X1 in the direction D1 in which the anode wire 112 extends, and the distance between the end 133se (end side) of the side wall 133s on the end face 113e side and the end face 113e, i.e., the distance Y1 in the direction D1. Further, Fig. 11C , also represents the length L1 of the anode body 113 in the direction D1. Further, Fig. 11C , the center 113c of the anode body 113 in the direction D1 is also shown.

[0149] The distance X1, the distance Y1 and the length L1 may be within the above ranges. The end 133ae of the plate-shaped portion 133a and the end 133se of the side wall 133s are both located closer to the end surface 113e than the center 113c of the anode body 113.

[0150] In the electrolytic capacitor 200, the volume between the cathode portion 115 and the two side walls 133s of the connecting portion 133 increases as the distance from the end face 113e of the anode body 113 increases. In another viewpoint, the area between the cathode portion 115 and the side wall 133s at the cross section perpendicular to the direction D1 increases as the distance from the end face 113e of the anode body 113 increases. With these structures, when the cathode portion 115 and the connecting portion 133 are bonded using the material (conductive material) of the conductive member 141, it is easy to guide the conductive material in a direction away from the end face 113e. Therefore, the above-mentioned effect can be obtained.

[0151] (Implementation method 3)

[0152] In Embodiment 3, another example of the second electrolytic capacitor will be described. Electrolytic capacitor 200a of Embodiment 3 is substantially different from electrolytic capacitor 200 of Embodiment 2 only in the shape of connection portion 133, and therefore duplicate descriptions are omitted.

[0153] Since the cross-sectional view of the electrolytic capacitor 200a along the direction D1 of the third embodiment is different from Fig. 9 The cross-sectional view of the electrolytic capacitor 200 shown is the same and therefore is omitted from illustration. Fig.12 Indicated in Fig. 9 A cross-sectional view of the electrolytic capacitor 200a at a position corresponding to the line XX. Fig.13A 2 shows a development view of the cathode lead terminal 130 of the third embodiment when the connection portion 133 is flattened. Fig. 13B 2 is a top view of the cathode lead terminal 130 . Fig. 13B , the position of the cathode portion 115 is also indicated. Fig. 13B, an angle α2 formed between the direction in which the upper side of the side wall 133s of the connection portion 133 extends and the side surface 115s of the cathode portion 115 (more specifically, the surface including the side surface 115s) is also shown. Fig. 11C Likewise, illustration is therefore omitted.

[0154] In Embodiment 3, plate-like portion 133a of connection portion 133 is rectangular. The distance between two side walls 133s of connection portion 133 and cathode portion 115 increases as the distance from end surface 113e of anode body 113 increases, and also increases as the distance from plate-like portion 133a increases.

[0155] In electrolytic capacitor 200a of Embodiment 3, the volume between cathode portion 115 and two side walls 133s of the connection portion increases as the distance from end surface 113e of anode body 113 increases. With this structure, the above-mentioned effects can be obtained.

[0156] (Implementation 4)

[0157] In Embodiment 4, an example of a third electrolytic capacitor will be described. Electrolytic capacitor 300 of Embodiment 4 is substantially different from electrolytic capacitor 200 of Embodiment 2 only in the shape of connection portion 133, and therefore duplicate descriptions are omitted.

[0158] Fig.14 , a cross-sectional view of the electrolytic capacitor 300 is shown. Fig.14 and Fig. 9 About the same. Fig.15 Indicated in Fig.14 A cross-sectional view taken along line XV-XV of FIG. Fig.16A 3 shows an expanded view of the connection portion 133 of the electrolytic capacitor 300 when it is flattened. Fig. 16B as well as Fig. 16C 3 and 4 respectively show a top view and a side view of the connection portion 133 .

[0159] The cathode lead terminal 130 of the electrolytic capacitor 300 includes a connection portion 133 connected to the cathode portion 115 via a conductive member 141. The connection portion 133 includes a plate-shaped portion 133a facing the bottom surface 115b of the cathode portion 115 with the conductive member 141 interposed therebetween, and two side walls 133s rising substantially vertically from the plate-shaped portion 133a. The two side walls 133s face the two side surfaces 115s of the cathode portion 115, respectively.

[0160] The conductive member 141 is disposed between the bottom surface 115b and the plate-shaped portion 133a and between the two side surfaces 115s and the two side walls 133s. That is, the conductive member 141 contacts and electrically connects the bottom surface 115b and the plate-shaped portion 133a and contacts and electrically connects the two side surfaces 115s and the two side walls 133s.

[0161] Fig. 16C , represents the distance between the end (end side) 133ae of the plate-shaped portion 133a on the end face 113e side and the end face 113e, that is, the distance X2 in the direction D2 in which the anode line extends. Further, Fig. 16C , represents the distance Y2 between the end portion (end side) 133se on the end face 113e side of the two side walls 133s and the end face 113e, that is, the distance in the direction D2. Fig. 16C , represents the length L2 of the anode body 113 in the direction D2. Further, Fig. 16C , the center 113c of the anode body 113 in the direction D2 is shown.

[0162] The relationship between the distance X2, the distance Y2 and the length L2 may be within the above range. Fig. 16C As shown, the end 133se on the end face 113e side of the two side walls 133s of the connection portion 133 is farther from the end face 113e than the end 133ae on the end face 113e side of the plate-shaped portion 133a. That is, the distance Y2 is greater than the distance X2.

[0163] In order to increase the area of ​​the conductive member 141, it is necessary to apply a large amount of the material of the conductive member 141, that is, the conductive material. On the other hand, in this case, there is a concern that a portion of the conductive material will extend from the connecting portion 133. With the above structure, the conductive material is easily extended from the end 133se. Since the end 133se is present at a position away from the anode line 112, even in the case where the conductive material extends from the connecting portion 133, it is possible to suppress the conductive material from reaching the anode line 112. In order to enhance this effect, when configuring the conductive material, it may also be configured at a position away from the end face 113e. For example, the conductive material may also be configured at a position farther away from the end face 113e than the center 113c. Alternatively, the conductive material may also be configured at a position farther away from the end face 113e than the end 133se.

[0164] The end 133ae and the end 133se are respectively located closer to the end surface 113e than the center 113c. This structure can increase the area connected by the conductive member 141. In this case, as described above, the conductive material used to form the conductive member 141 can be prevented from reaching the anode line 112.

[0165] In Embodiments 2 to 4, an example is described in which the plate-shaped portion 133a of the connection portion 133 faces the bottom surface 115b of the cathode portion 115 with the conductive member 141 interposed therebetween. However, the plate-shaped portion 133a may be arranged to face the top surface 115t of the cathode portion 115 with the conductive member 141 interposed therebetween. In this case, the two side walls 133s extend from the plate-shaped portion 133a toward the bottom surface 115b.

[0166] In the electrolytic capacitor 200 of the second or third embodiment, the groove described in the first embodiment may be formed in the connecting portion 133. In this case, as described in the fourth embodiment, the ends of the two side walls 133s of the connecting portion 133 on the end face 113e side may be further away from the end face 113e than the ends of the plate-like portion 133a on the end face 113e side.

[0167] In the electrolytic capacitor of Embodiment 1 or 2, as described in Embodiment 4, the ends of two side walls 133s of connecting portion 133 on the end face 113e side may be farther away from end face 113e than the ends of plate-shaped portion 133a on the end face 113e side.

[0168] Industrial Applicability

[0169] The present disclosure can be utilized in electrolytic capacitors.

[0170] The present invention has been described with respect to the currently preferred embodiments, but the disclosure is not to be construed in a limiting sense. Upon reading the above disclosure, various modifications and changes will undoubtedly be apparent to those skilled in the art in the technical field to which the present invention belongs. Therefore, it should be construed that the claims include all modifications and changes without departing from the true spirit and scope of the present invention.

[0171] -Explanation of symbols-

[0172] 100, 200, 200a, 300: electrolytic capacitors

[0173] 101: Exterior resin

[0174] 110: Capacitor element

[0175] 112: Anode wire

[0176] 113: Anode

[0177] 113e: End face

[0178] 114: Dielectric layer

[0179] 115: Cathode

[0180] 115b: Bottom

[0181] 115sa: Side 1

[0182] 115sb: Side 2

[0183] 115t: Upper surface

[0184] 120: Anode lead terminal

[0185] 130: Cathode lead terminal

[0186] 133, 213333: Connection

[0187] 133a, 133a, 133a: plate-shaped part

[0188] 133g, 133z: Slot

[0189] 133ga: Slot 1

[0190] 133gb: Slot 2

[0191] 133s: Sidewall

[0192] 133sa: 1st side wall

[0193] 133sb: 2nd side wall

[0194] 133z: Slot

[0195] 141: Conductive member.

Claims

1. An electrolytic capacitor comprising: a capacitor element, an anode lead terminal and a cathode lead terminal electrically connected to the capacitor element, a conductive member, and an outer resin disposed around the capacitor element, The capacitor element includes: an anode body which is a porous sintered body having a dielectric layer formed on the surface, an anode wire protruding from an end surface of the anode body, and a cathode portion arranged adjacent to the dielectric layer. The cathode portion has a first side surface and a second side surface, and a bottom surface and an upper surface connecting the first side surface and the second side surface. The cathode lead terminal includes a connection portion connected to the cathode portion via the conductive member. The connecting portion includes: a plate-shaped portion sandwiching the conductive member and facing any one of the bottom surface and the top surface; and a first side wall and a second side wall rising from the plate-shaped portion and facing the first side surface and the second side surface, respectively. A plurality of grooves are formed on the surface of the plate-like portion, the first side wall, and the second side wall on the cathode portion side. The plurality of grooves include: a plurality of first grooves formed to be connected from the plate-shaped portion to the first side wall, and a plurality of second grooves formed to be connected from the plate-shaped portion to the second side wall. The conductive member is arranged between the one surface and the plate-shaped portion, between the first side surface and the first side wall, and between the second side surface and the second side wall. The grooves formed in the first side wall and the second side wall among the plurality of grooves are formed so as to be farther away from the end surface as they are farther away from the plate-shaped portion.

2. The electrolytic capacitor according to claim 1, wherein: In the first groove, the conductive member is arranged so as to be connected from the plate-shaped portion to the first side wall. In the second groove, the conductive member is arranged so as to be connected from the plate-shaped portion to the second side wall.

3. The electrolytic capacitor according to claim 1 or 2, wherein: The plurality of first grooves are respectively connected to corresponding grooves among the plurality of second grooves to form one groove, The plurality of grooves are connected from the plate-shaped portion to the first side wall and the second side wall.

4. The electrolytic capacitor according to claim 1 or 2, wherein: The plurality of grooves extend in directions substantially perpendicular to a direction in which the anode wires extend, respectively.

5. The electrolytic capacitor according to claim 1 or 2, wherein: A groove is also formed on a surface of the plate-like portion, the first side wall, and the second side wall on a side opposite to the surface on the cathode side. The exterior resin is disposed in the groove on the opposite surface.

6. The electrolytic capacitor according to claim 1 or 2, wherein: An end portion of the first side wall on the end surface side and an end portion of the second side wall on the end surface side are each farther from the end surface than an end portion of the plate-shaped portion on the end surface side.

7. An electrolytic capacitor comprising: a capacitor element, an anode lead terminal and a cathode lead terminal electrically connected to the capacitor element, a conductive member, and an outer resin disposed around the capacitor element, The capacitor element includes: an anode body which is a porous sintered body having a dielectric layer formed on the surface, an anode wire protruding from an end surface of the anode body, and a cathode portion arranged adjacent to the dielectric layer. The cathode portion has a first side surface and a second side surface, and a bottom surface and an upper surface connecting the first side surface and the second side surface. The cathode lead terminal includes a connection portion connected to the cathode portion via the conductive member. The connecting portion includes: a plate-shaped portion sandwiching the conductive member and facing any one of the bottom surface and the top surface; and a first side wall and a second side wall rising from the plate-shaped portion and facing the first side surface and the second side surface, respectively. A plurality of grooves are formed on the surface of the plate-like portion, the first side wall, and the second side wall on the cathode portion side. The plurality of grooves include: a plurality of first grooves formed to be connected from the plate-shaped portion to the first side wall, and a plurality of second grooves formed to be connected from the plate-shaped portion to the second side wall. The conductive member is arranged between the one surface and the plate-shaped portion, between the first side surface and the first side wall, and between the second side surface and the second side wall. The volume between the cathode portion and the first side wall and the volume between the cathode portion and the second side wall increase as they are farther away from the end surface.

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