JP3396902B2 - Solid electrolytic capacitor and method of manufacturing the same - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solid electrolytic capacitor in which the side faces of two strip-shaped chips are bonded together to form an anode body, and a method for manufacturing the same.

[0002]

2. Description of the Related Art Conventionally commercially available solid electrolytic capacitors have, for example, a surface of an anode body (anode foil) made of a valve metal such as aluminum or tantalum, which is roughened by etching, and an oxide film is formed on the surface. Each layer of the electrolyte is sequentially generated, and a cathode body (cathode foil) is disposed on or without a conductive layer if necessary, and lead terminals are respectively pulled out from the anode body and the cathode body, and the anode body is also formed. Also, the cathode body is sealed with a resin sheath. Each lead terminal of the anode and the cathode is bent along the wall surface of the resin exterior.

[0003]

As described above, in the conventional solid electrolytic capacitor, the cathode body is laminated on the anode body via the above-mentioned layers, so that the bonding strength is not so strong. Also, since the capacitor element is sealed only by the resin exterior, the airtightness is not so high. Furthermore, since the anode lead terminal is connected to the anode body through the oxide film, the connection strength is slightly lower. It becomes a cause of unstable connection and there is a problem in reliability of connection. Also, when connecting the anode lead terminals, a large amount of electric energy and thermal energy must be used when welding to the anode body. Therefore, the required output at the time of connection is increased, which causes a problem that the leakage current that affects the characteristics of the capacitor is increased. The conventional solid electrolytic capacitor has many problems to be solved, such as the above-mentioned problems occurring in the manufacturing process.

The present invention has been proposed in view of the above points, and in a solid electrolytic capacitor in which two pieces of chip-shaped chips are bonded together to form an anode body, the bonding strength of the chip-shaped chips is improved, and The purpose of the present invention is to improve the airtightness of the capacitor element, increase the connection strength of the anode lead terminal, improve the stability and reliability of the connection, and eliminate the cause of the leakage current increase.

[0005]

In order to achieve the above object, the present invention is a two-piece chip-shaped chip in which an oxide film layer and an electrolyte layer made of an organic conductive polymer are sequentially formed on an etched surface. The cathode lead terminal is sandwiched by the respective one side surfaces of the cathode lead terminal so that the anode body is led out from one end surface of the anode body, and the surface of the anode body is covered with the first resin by resin dipping. In addition, exposing the chip material on the other end surface of the anode body opposite to the end surface from which the cathode lead terminal is led out, connect the anode lead terminal to the other end surface, and connect the anode lead terminal from the other end surface. A structure was adopted in which the cathode lead wire was extended in the opposite direction and the anode body was sealed with a second resin sheath.

Further, in order to achieve the above object, the present invention provides one of two pieces of chip-shaped chips in which an oxide film layer and an electrolyte layer made of an organic conductive polymer are sequentially formed on an etched surface. By sticking so that the cathode lead terminal is sandwiched by the side surface, to form an anode body in which the cathode lead terminal is led out from one end surface, then, the surface of the anode body is covered with a first resin by resin dipping, After that, each layer of the resin, the electrolyte, and the oxide film is removed from the other end surface of the anode body opposite to the end surface from which the cathode lead is led out, the chip material is exposed on the other end surface, and the material is exposed. An anode lead terminal is connected to the end face, the anode lead terminal is extended in the opposite direction to the cathode lead terminal, and then the anode body is covered with a second resin sheath. Adopting a method of manufacturing a solid electrolytic capacitor, characterized in that the stop.

[0007]

With the two pieces of the chip-shaped chips, the cathode lead terminals are sandwiched and adhered to each other, whereby the two chips are firmly bonded to each other to form an anode body having a strong bonding strength. In addition, since the anode body is covered with the first resin on the surface and then the outer periphery is further sealed with the second resin exterior, the sealing structure of the capacitor element becomes a double structure, and a more reliable sealing is achieved. You can stop.

Further, the chip material on the other end surface of the anode body opposite to the end surface from which the cathode lead terminal is led out is exposed,
Since the anode lead terminal is directly attached to this exposed surface, the connection is reliable, the connection strength is high, and the connection stability is improved. Furthermore, since it is attached directly to the exposed surface, the amount of electrical and thermal energy consumed when welding the anode lead terminal to the anode body is small, and reliable connection can be achieved, while at the same time increasing leakage current. It is possible to suppress the increase in the required output at the time of connection, which is a factor of.

[0009]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a solid electrolytic capacitor according to the present invention, and FIGS. 2A to 2G show process steps of the method for manufacturing the solid electrolytic capacitor.

In FIGS. 1 and 2A to 2G, the anode body 10 has a structure in which one side surface of two piece chips 101 and 102 is attached. Two-piece chip 10
The reference numerals 1 and 102 are made of a valve action metal material such as aluminum or tantalum. The anode lead terminal 20 drawn out from the anode body 10 is formed by previously bending a plate-like body made of a metal material such as aluminum or tantalum into a substantially L shape. Further, the cathode lead terminal 30 is formed by previously bending a plate-like body made of a valve action metal material similar to the anode lead terminal 20 into a crank shape.

The two pieces of the chip-shaped chips 101 and 102 have their surfaces roughened in advance by etching, and an oxide film layer 103 and an electrolyte layer 104 made of an organic conductive polymer are sequentially formed on the surfaces.

Next, the manufacturing process / procedure of the solid electrolytic capacitor according to the present invention using the above-mentioned constituent members will be described.

As shown in FIG. 2A, one end of each of the two pieces of the chip-shaped chips 101 and 102 is sandwiched by one side surface of the cathode lead terminal 30 so as to sandwich the two pieces of the chip-shaped chips 101 and 102. Are bonded and fixed, the anode body 10 in which the two pieces of the chip-shaped chips 101 and 102 are bonded together is formed. Two piece chips 101 of this anode body 10,
The cathode lead terminal 30 is extended to one side from between 102, and the cathode lead terminal 30 is led out from one end surface of the anode body 10. Then, the cathode lead terminal 30
The intermediate bent portion 300 bent in the crank shape is separated from the one end surface of the anode body 10 by a constant distance d.

Next, as shown in FIG. 2B, the anode body 1
0 is immersed in the resin dip tank 40. A molten resin 41 is contained in the tank 40, and the anode body 1 is contained therein.
When 0 is immersed, the anode body 10 is formed by resin dipping.
Is covered with the first resin 41. afterwards,
Anode body 10 is taken out from dip tank 40. Then, as shown in FIG. 2C, the first resin 41 attached to the surface of the anode body 10 is dried and cured. First resin 4
As the first example, a thermosetting resin such as epoxy or PPS (polyphenylene sulfide) is used in this embodiment. As shown in FIG. 2C, a gap d is provided between the intermediate bent portion 300 of the cathode lead terminal 30 and one end surface of the anode body 10.
Since the resin 41 covering the surface of the anode body 10 is interposed therebetween, the short-circuit phenomenon between the anode body 10 and the cathode lead terminal 30 is reliably prevented, and the short-circuit phenomenon does not occur. . The lead part of the cathode lead terminal 30 is
It is preliminarily offset by a distance of h with respect to the holding section.

After the drying / curing step of FIG. 2C is completed, as shown in FIG. 2D, the anode body 10 is turned upside down, and the other end surface opposite to the end surface from which the cathode lead terminal is led out. (Upper surface) is the grinding step, and the grindstone 61 of the grinder 60
To be ground by. As a result, the resin 41, the electrolyte layer 104, and the oxide film layer 10 are formed from the other end surface of the anode body 10.
3 and two pieces of the chip 101, 1 of the anode body 10.
The surface layer of No. 02 is ground and removed, and the material of the flaky chips 101, 102 is exposed at the other end surface of the anode body 10.

Next, as shown in FIG. 2E, the L-shaped base portion 21 of the anode lead terminal 20 is directly attached and connected to the other end surface of the anode body 10 where the chip material is exposed. This connection is made, for example, by welding. Then, the anode lead terminal 20 extends from the other end surface of the anode body 10 to the other side, that is, in the direction opposite to the drawing direction of the cathode lead terminal 30. Both lead terminals 20 and 30 are arranged on substantially the same line in the drawing direction. When the step of connecting the lead terminals 20 in FIG. 2E is completed, a capacitor element as shown in the figure is manufactured.

Thereafter, in the step of FIG. 2F, the anode body 10 is sealed by the second resin sheath 50 as shown in the figure. A thermosetting resin is used as the resin. Next, in the bending step of FIG. 2G, the lead terminals 20 and 30 of the anode and the cathode are bent along the wall surface of the resin sheath 50. During this bending process, the electrical characteristics of the capacitor are simultaneously inspected. Then, when the bending process of the lead terminals 20 and 30 is completed, as shown in FIG. 1, the solid electrolytic capacitor according to the present embodiment is manufactured, and the manufacturing of a single capacitor is completed.

[0019]

As is apparent from the above description, according to the present invention, the following effects can be obtained.

Since one side surface of each of the two pieces of the chip-shaped chips is bonded to form an anode body, the two pieces of the chip-shaped chips can be bonded securely and firmly, and the bonding strength can be improved. improves.

Since the surface of the anode body is covered with a resin and the surface is sealed with a resin sheath,
The sealing structure will be a double exterior, and more reliable and complete sealing can be performed. Therefore, the airtightness is significantly improved as compared with the conventional structure.

Since the anode lead terminal is directly connected to the other end surface of the anode body where the chip material is exposed, the connection is reliable, the connection strength is remarkably strong, and the connection stability is improved. Further, the amount of electrical and thermal energy used at the time of connection can be small, and at the same time, reliable connection can be achieved, and at the same time, the output used at the time of connection can be reduced, and as a result, the cause of increase in leakage current can be eliminated.

[Brief description of drawings]

FIG. 1 is a front sectional view of a solid electrolytic capacitor according to the present invention.

2] (a), (b), (c), (d), (e),
(F) and (G) are front sectional views showing process steps of the method for manufacturing a solid electrolytic capacitor according to the present invention.

[Explanation of symbols]

10 Anode body 101, 102 flaky chips 103 Oxide film layer 104 electrolyte layer 20 Anode lead terminal 21 L-shaped base 30 cathode lead terminal 300 Middle bend d Distance h Offset amount 41 First Resin 50 Second resin exterior

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Claims (2)

(57) [Claims] 1. A cathode lead terminal is attached such that an oxide film layer and an electrolyte layer made of an organic conductive polymer are sequentially formed on the etched surface so that the cathode lead terminal is sandwiched by one side surface of each piece. By forming an anode body from which the cathode lead terminal is led out from one end face, and by coating the surface of the anode body with a first resin by resin dipping, the end face of the anode body from which the cathode lead terminal is led out Exposing the chip material on the other end surface on the opposite side to the other end surface, connecting an anode lead terminal to the other end surface, and extending the anode lead terminal from the other end surface in a direction opposite to the cathode lead wire; A solid electrolytic capacitor, characterized in that is sealed with a second resin exterior. 2. A cathode lead terminal is attached by sandwiching a cathode lead terminal by one side of each of two pieces of chip-shaped chips in which an oxide film layer and an electrolyte layer made of an organic conductive polymer are sequentially formed on an etched surface. The cathode lead terminal is led out from one end surface of the anode body by forming a cathode lead terminal, and then the surface of the anode body is covered with a first resin by resin dipping, and then the cathode lead of the anode body is led out. The respective layers of the resin, electrolyte and oxide film are removed from the other end surface opposite to the end surface, the chip material is exposed on the other end surface, and the anode lead terminal is connected to the other end surface where the material is exposed, and the anode A solid electrolytic capacitor, characterized in that a lead terminal is extended in a direction opposite to that of the cathode lead terminal, and then the anode body is sealed with a second resin sheath. Manufacturing method.