JP2009099877A - Solid electrolytic capacitor, and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a solid electrolytic capacitor excelling in an ESR characteristic, in a solid electrolytic capacitor with a plurality of capacitor elements arranged in parallel to one another therein. <P>SOLUTION: The solid electrolytic capacitor includes a plurality of capacitor elements each having a positive electrode part and a negative electrode part, and is structured such that the plurality of capacitors adjacent to one another are arranged in parallel to one another so that the positive electrode parts adjoin one another and the negative electrode parts adjoin one another; and the negative electrode parts are connected to a negative electrode lead frame. The solid electrolytic capacitor is characterized in that the negative electrode parts are connected to the negative electrode lead frame on at least three faces including a surface nearly vertical to a direction in which the positive electrode parts and the negative electrode parts continue, a surface of the negative electrode lead frame nearly vertical to the direction in which the positive electrode parts and the negative electrode parts continue has a filling part, and the filling part is filled with an armoring resin. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

The present invention relates to a solid electrolytic capacitor in which a plurality of capacitor elements are arranged in parallel so that anode leads are in the same direction.

  Conventional chip-type solid electrolytic capacitors include a cathode lead frame and a part of a cathode lead layer of a capacitor element in which a dielectric film, a cathode layer, and a cathode lead layer are sequentially formed on the surface of a sintered body made of a valve metal. After electrically and mechanically connecting the anode lead connected to the sintered body and the anode lead frame, respectively, the capacitor element is made of an exterior resin while leaving a part of the anode lead frame and the cathode lead frame. It is known that the anode lead frame and the cathode lead frame that are coated and not coated with the exterior resin are bent along the exterior resin.

  On the other hand, a solid electrolytic capacitor having good high frequency performance is desired in response to the higher frequency of electronic equipment in recent years. In the case of a solid electrolytic capacitor using a sintered body as described above, a sintered body In order to maintain the strength of the sintered body, it is necessary to increase the thickness of the sintered body to some extent, and thus good high frequency characteristics could not be obtained.

In order to solve the above problem, as shown in FIG. 12, a plurality of capacitor elements 1 are placed in parallel so that the anode leads face in the same direction without gaps, and the cathode lead layers and cathodes of the plurality of capacitor elements 1 A structure of a solid electrolytic capacitor in which the lead frame 3 is connected to the anode lead frame 2 and the anode lead frame 2 has been proposed. (For example, Patent Document 1)
However, in the structure of FIG. 12, the leakage current characteristic is not good, and improvement of the leakage current characteristic has been demanded. In order to meet this requirement, as shown in FIG. 13, a method of fixing the cathode layers of a plurality of capacitor elements using a fixing layer 6 such as resin or conductive paste has been proposed. (For example, Patent Document 2)
Japanese Patent Application Laid-Open No. 05-234829. JP-A-2005-93994.

  However, the structures as shown in FIGS. 12 and 13 have a limited contact area between the cathode layer and the cathode lead frame, and the ESR (equivalent series resistance) effect of the capacitor is not sufficient.

A plurality of capacitor elements having an anode part and a cathode part are provided, and the plurality of adjacent capacitor elements are arranged in parallel so that the anode parts and the cathode parts are adjacent to each other, and the cathode part and the cathode lead frame are In the connected solid electrolytic capacitor, the cathode portion is connected to the cathode lead frame on at least three surfaces including a surface substantially perpendicular to a direction in which the anode portion and the cathode portion are connected, and the anode portion and The cathode lead frame has a filling portion on a surface substantially perpendicular to a direction in which the cathode portions are continuous, and the filling portion is filled with an exterior resin.

  By adopting the above structure, the cathode lead frame can be connected to the capacitor element across a large number of surfaces, and the ESR of the capacitor can be reduced. Further, since the cathode lead frame has a filling portion, and the filling portion is filled with the exterior resin, the adhesion between the capacitor element and the exterior resin is improved.

  Further, in the solid electrolytic capacitor of the present invention, the cathode lead frame is a surface that is substantially parallel to a direction in which the anode portion and the cathode portion are connected, and is connected to a surface that is substantially perpendicular to a direction in which the anode portion and the cathode portion are connected. About, it has a filling part and this exterior part may be filled with exterior resin. With such a structure, the adhesion between the capacitor element and the exterior resin can be improved without increasing the ESR of the solid electrolytic capacitor.

  Furthermore, in the solid electrolytic capacitor, the cathode portion is formed on a peripheral surface of the anode body, and the anode portion includes an anode lead planted on the anode body, and the anode lead of the anode body is implanted. The distance between the surface where the cathode lead frame and the cathode portion are connected and the anode lead is the distance between the surface where the cathode lead frame and the cathode portion are not connected and the anode lead. Desirably smaller than the distance. The smaller the distance between the anode lead and the cathode lead frame, the greater the ESR reduction effect of the capacitor.

  In the method of manufacturing a solid electrolytic capacitor having the above structure, the cathode lead frame has a flat plate shape, a cut is made in the flat lead frame, the capacitor element is placed inside the cut, and the outside of the cut is outside the cut. The connection is made by bending along the peripheral surface of the cathode portion.

  The solid electrolytic capacitor manufactured as described above has a large contact portion between the cathode lead frame and the cathode portion, and further, the cathode lead frame is made of a single body having no joint portion, and therefore, through a conductive paste or the like. Compared with the case of connecting to another metal terminal, the current collecting property is better and a significant ESR reduction effect of the capacitor can be expected.

  Another form of the solid electrolytic capacitor of the present invention includes a plurality of capacitor elements each having an anode part and a cathode part, and the plurality of adjacent capacitor elements are adjacent to each other between the anode part and the cathode part. In the solid electrolytic capacitor in which the cathode part and the cathode lead frame are connected in parallel, the cathode part is at least three of the faces substantially parallel to the direction in which the anode part and the cathode part are connected. The cathode lead frame is connected to the cathode lead frame.

  With the structure as described above, the cathode lead frame is connected over a large number of surfaces of the capacitor element, so that the ESR of the solid electrolytic capacitor can be reduced.

  By adopting the structure of the present invention, since the cathode portion and the cathode lead frame are connected over many surfaces of the capacitor element, the ESR of the solid electrolytic capacitor can be reduced. In addition, since at least a part of the cathode lead frame is provided with a filling portion, and resin is contained in the filling portion, the adhesion between the capacitor element and the exterior resin can be improved.

The best mode for carrying out the present invention will be described with reference to the drawings.
(Embodiment 1)
FIG. 1 is a top perspective view of the solid electrolytic capacitor according to the first embodiment of the present invention. FIG. 2 is a perspective view of the solid electrolytic capacitor of FIG. 1 viewed from the X direction and a perspective view viewed from the Y direction. FIG. 3B is a diagram showing the positional relationship between the capacitor element and the cathode lead frame in FIG. 1 as viewed from the Z direction and FIG. 3B is a diagram as viewed from the X direction.

  The solid electrolytic capacitor of the present invention comprises a capacitor element composed of an anode part 1 and a cathode part 2, a cathode lead frame 3 and an anode lead frame 4, and the peripheral surface of the capacitor element is covered with an exterior resin 5. . The cathode lead frame 3 includes a lower surface portion 31 on which a capacitor element is placed, a side surface portion 32 substantially perpendicular to the lower surface portion 31, and an upper surface substantially perpendicular to the side surface portion 32 and substantially parallel to the lower surface portion. The lower surface portion 31, the side surface portion 32, and the upper surface portion 33 are respectively connected to the lower surface, the side surface, and the upper surface of the cathode portion 2 of the capacitor element. Further, the side surface portion 32 and the upper surface portion 33 have filling portions 32a and 33a, respectively, and the filling portions 32a and 33a are filled with the exterior resin 5.

  The cathode lead frame 3 has a terminal portion 34 that continues from the side surface portion 32, and the terminal portion 34 is exposed from the exterior resin 5 and is bent along the exterior resin 5.

As shown in FIG. 3A, the distance m from the center of the anode part 1 to the lower surface part 31 and the upper surface part 33 is the distance from the center of the anode part 1 to the side surface of the cathode part 4 not in contact with the cathode lead frame 3. It is smaller than n.
(Embodiment 2)
FIG. 4 is a top perspective view of the solid electrolytic capacitor according to the second embodiment of the present invention, and FIG. 5 is a perspective view of the solid electrolytic capacitor of FIG. 4 viewed from the X direction and a perspective viewed from the Y direction. FIG. 6B is a diagram in which the positional relationship between the capacitor element and the cathode lead frame in FIG. 4 is viewed from the Z direction and FIG. 6B is a diagram from the X direction.

  The solid electrolytic capacitor according to the second embodiment includes a capacitor element including an anode part 1 and a cathode part 2, a cathode lead frame 3 and an anode lead frame 4, and the peripheral surface of the capacitor element is covered with an exterior resin 5. Yes. The cathode lead frame 3 includes a lower surface portion 31 on which a capacitor element is placed, a side surface portion 32 substantially perpendicular to the lower surface portion 31, and an upper surface substantially perpendicular to the side surface portion 32 and substantially parallel to the lower surface portion 31. The lower surface portion 31, the side surface portion 32, and the upper surface portion 33 are respectively connected to the lower surface, the side surface, and the upper surface of the cathode portion 2 of the capacitor element. The side surface portion 32 has a filling portion 32a, and the filling portion 32a is filled with the exterior resin 5.

  In this solid electrolytic capacitor, the distance m between the center of the anode portion 1 of the capacitor element and the lower surface portion 31 and the upper surface portion 33 of the cathode lead frame 3 is a cathode that is not in contact with the center of the anode portion 1 and the cathode lead frame 3. It is smaller than the distance n with the side surface of the part 2.

  Next, the manufacturing method of the solid electrolytic capacitor of Embodiment 2 is demonstrated.

  A capacitor element comprising an anode portion 1 and a cathode portion 2 formed by a conventionally known method is arranged such that the anode portion 1 is on the anode lead frame 4 and the cathode portion 2 is on the cathode lead frame 3 of the lead frame shown in FIG. The anode part 1 and the anode lead frame 4, and the cathode part 2 and the cathode lead frame 3 are connected by a known method. At this time, the cathode portion 2 is placed on the lower surface portion 31 of the cathode lead frame 3. Further, the distance between the center of the anode portion 1 of the capacitor element and the surface to which the cathode lead frame 3 and the cathode portion 2 are connected is such that the center of the anode portion 1 and the surface of the cathode portion not connected to the cathode lead frame 3. The capacitor element is disposed on the lead frame so as to be smaller than the distance between the lead frame and the capacitor.

  Here, as shown in FIG. 7, the cathode lead frame 3 has a cut in part, and the inner side of the cut is a lower surface portion 31 and the outer side is a side surface portion 32. An upper surface portion 33 is provided on the side facing the side surface portion 32 and facing the anode lead frame 4. The side surface portion 32 and the upper surface portion 33 are raised while leaving the lower surface portion 31, and only the upper surface portion 33 is bent, and the side surface portion 32 and the side surface of the cathode portion 2 and the upper surface portion 33 and the upper surface of the cathode portion 2 are well known. Connect by method. Further, when the cut portion of the cathode lead frame 3 is extended to the upper surface portion 33 side, the cathode lead frame 3 used in the above-described first embodiment is obtained. The lead frame 4 and the cathode lead frame 3 can be connected.

After the anode lead frame 4 and the cathode lead frame 3 and the capacitor element are connected as described above, the peripheral surface of the capacitor element is covered with the exterior resin 5 using a conventionally known technique to produce a solid electrolytic capacitor.
(Embodiment 3)
FIG. 8 is a top perspective view of another embodiment of the present invention, and FIG. 9 is a perspective view (a) of the solid electrolytic capacitor of FIG. 8 viewed from the X direction and a perspective view (b) viewed from the Y direction. FIG. 10 is a view of the positional relationship between the capacitor element and the cathode lead frame in FIG. 8 as viewed from the Z direction (a) and the X direction (b) in FIG.

  The solid electrolytic capacitor of Embodiment 3 includes a plurality of capacitor elements each including an anode portion 1 and a cathode portion 2, an anode lead frame 4 and a cathode lead frame 3, and the periphery of the capacitor element is covered with an exterior resin 5. . Here, the cathode lead frame 3 includes a side plate 35 and a terminal portion 34 as shown in FIG. 11, and the distance between the side plates 35 is arranged to be substantially equal to the width of the capacitor element. The lower surface of the terminal portion 34 and the lower surface of the anode lead frame 4 are exposed from the exterior resin 5. Both ends of the side plate 35 are substantially flush with the terminal portion 34 and are connected to the terminal portion 34 so as to rise substantially vertically. However, it is also possible to use a shape that is originally raised. It is.

  In the solid electrolytic capacitor, the distance between the center of the anode part 1 of the capacitor element and the side plate 35 is smaller than the distance between the center of the anode part 1 and the terminal part 34.

  A manufacturing method for the solid electrolytic capacitor of Embodiment 3 will be described below.

  A capacitor element having an anode portion 1 and a cathode portion 2 manufactured by a conventionally known method is connected to an anode lead frame 4 and a cathode lead frame 3. As the cathode lead frame 3, a cathode lead frame 3 as shown in FIG. Specifically, the capacitor element is connected by a known method such that the anode part 1 is on the anode lead frame 4 and the cathode part 2 is on the terminal part 34 between the side plates 35 of the cathode lead frame 4. Here, after the cathode part 2 of the capacitor element and the terminal part 34 of the cathode lead frame 3 are connected first, the side plate 35 may be raised and connected in accordance with the width of the capacitor element. The side plate 35 and the cathode part 2 are connected via a conductive paste or the like.

After connecting the capacitor element to the anode lead frame 4 and the cathode lead frame 3 as described above, the lower surface of the anode lead frame 4 and the lower surface of the cathode lead frame 3 are left and covered with the exterior resin 5 to complete the solid electrolytic capacitor. To do.
The above embodiments are merely for explaining the present invention, and should not be construed as limiting the invention described in the claims. The present invention can be freely modified within the scope of the claims and the scope of equivalent meanings. For example, in the second embodiment, the anode lead frame 4 may have a flat plate shape, and the anode 1 of the capacitor element and the anode lead frame 4 may be connected via a conductive member. Further, in all the embodiments, the capacitor element may be a foil-like element, and the number of capacitor elements is not particularly limited as long as it is plural, and need not necessarily be two.

It is an upper surface perspective view of the solid electrolytic capacitor of Embodiment 1 of the present invention. It is a perspective view when the solid electrolytic capacitor of FIG. 1 is seen from the X and Y directions. FIG. 2 is a diagram when the positional relationship between the capacitor element and the cathode lead frame in FIG. 1 is viewed from the Z and X directions. It is a top perspective view of the solid electrolytic capacitor of Embodiment 2 of the present invention. It is a perspective view when the solid electrolytic capacitor of FIG. 4 is seen from the X and Y directions. FIG. 5 is a perspective view when the positional relationship between the capacitor element and the cathode lead frame in FIG. 4 is viewed from the Z and X directions. It is a top view of the lead frame used for the solid electrolytic capacitor of FIG. It is a top perspective view of the solid electrolytic capacitor of Embodiment 3 of the present invention. It is a perspective view when the solid electrolytic capacitor of FIG. 8 is seen from the X and Y directions. It is a figure when the arrangement | positioning relationship between the capacitor | condenser element of FIG. 8 and a cathode lead frame is seen from the Z and X directions. It is a perspective view of the cathode lead frame used for the solid electrolytic capacitor of FIG. It is a perspective perspective view of the conventional solid electrolytic capacitor. It is a perspective perspective view of another conventional solid electrolytic capacitor.

Explanation of symbols

・ Anode part ・ Cathode part ・ Cathode lead frame ・ Anode lead frame ・ Exterior resin ・ Fixed layer

Claims (6)

A plurality of capacitor elements each having an anode part and a cathode part are provided, and a plurality of adjacent capacitor elements are arranged in parallel so that the anode parts and the cathode parts are adjacent to each other, and the cathode part and the cathode lead frame are In the connected solid electrolytic capacitor,
The cathode portion is connected to the cathode lead frame on at least three surfaces including a surface substantially perpendicular to a direction in which the anode portion and the cathode portion are continuous.
In a plane substantially perpendicular to the direction in which the anode part and the cathode part are connected,
The cathode lead frame has a filling portion, and the filling portion is filled with an exterior resin. The cathode lead frame has a surface that is substantially parallel to a direction in which the anode portion and the cathode portion are connected and is connected to a surface that is substantially perpendicular to a direction in which the anode portion and the cathode portion are connected. In a continuous aspect,
The solid electrolytic capacitor according to claim 1, wherein the cathode lead frame has a filling portion, and the filling portion is filled with an exterior resin. The cathode part is formed on a peripheral surface of an anode body, and the anode part is a solid electrolytic capacitor including an anode lead planted on the anode body.
On the surface of the anode body where the anode lead is planted, the distance between the surface where the cathode lead frame and the cathode portion are connected and the anode lead is the same as the distance between the cathode lead frame and the cathode portion. 3. The solid electrolytic capacitor according to claim 1, wherein the solid electrolytic capacitor is smaller than a distance between a non-surface and the anode lead. A plurality of capacitor elements having an anode part and a cathode part are provided, and the plurality of adjacent capacitor elements are arranged in parallel so that the anode part and the cathode part are located in the same direction, and the cathode part and the cathode lead In the solid electrolytic capacitor to which the frame is connected,
The solid electrolytic capacitor, wherein the cathode portion is connected to the cathode lead frame on at least three surfaces among surfaces substantially parallel to a direction in which the anode portion and the cathode portion are continuous. The cathode part is formed on a peripheral surface of an anode body, and the anode part is a solid electrolytic capacitor including an anode lead planted on the anode body.
In the surface of the anode body on which the anode lead is planted, the distance between the surface where the cathode portion is connected to the opposite surface of the cathode portion and the anode lead is the cathode lead frame. 5. The solid electrolytic capacitor according to claim 4, wherein the distance is smaller than the distance between the surface where the cathode part is not connected to the anode lead. In the manufacturing method of the solid electrolytic capacitor in any one of Claims 1 thru | or 3,
The cathode lead frame has a flat plate shape, a rectangular cut is made in the flat lead frame, the capacitor element is placed inside the cut, and the outside of the cut is bent along the peripheral surface of the cathode portion. And a solid electrolytic capacitor manufacturing method.

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