JPH01251605A - Solid electrolytic capacitor - Google Patents

Abstract

PURPOSE:To prevent short circuit caused by burrs on an electrode foil created when the foil is cut, by forming the cut edges of the electrode foil or of an anode and/or cathode foil such that they are located inside of the top and rear faces of the electrode foil or of the anode and/or cathode foil. CONSTITUTION:The cut-out edges of an aluminum plate 1 are pressed such that cross section thereof is wedge-shaped 2, protruding, semi-circular, rounded or inclined. The aluminum plate 1 is welded to an anode lead 3. The aluminum plate having the lead 3 is subjected to chemical conversion treatment with a chemical conversion solution 5 such that the welded section 4 is not brought into contact with the solution 5. Thereby, an anode oxide film 6 is formed on the plate. A chemically polymerized film 7 is produced on the anode oxide film 6. The film 7 is used as the plus pole and the minus pole is provided near there so that an electrolytic treatment is performed and an electrolytically polymerized film 8 is produced on the chemically polymerized film 7. According to such method, no burr is created on the top or rear face of the aluminum plate 1 and, therefore, problems such as short circuit or the like can be prevented effictively since the coat films such as the electrolytically polymerized film 8 is not peeled off to expose the aluminum plate by burrs on the plate.

Description

Detailed Description of the Invention [Object of the Invention] (Industrial Application Field) The present invention relates to a solid electrolytic capacitor using an organic semiconductor such as a TCNQ complex or a solid electrolyte such as an electrolytically polymerized film.

(Prior Art) Conventionally, in an electrolytic capacitor using a solid electrolyte, for example, an aluminum foil is roughened, a dielectric oxide film is formed, and an anode lead terminal is connected to the aluminum foil. After forming a TCNQ complex or a chemically polymerized film on the oxide film, a solid electrolyte is generated by forming an electrolytically polymerized film on the chemically polymerized film, and graphite and conductive paint are applied to this solid electrolyte. Use as cathode layer. A cathode lead-out terminal was connected to this cathode layer to form a capacitor element, and the capacitor element was covered with resin as necessary. There are two types of capacitor elements: one in which only electrode foil is wound or laminated, and another in which an anode foil and a cathode foil are used, or a capacitor paper or the like is used between the anode foil and the cathode foil. There are some with spacers interposed, and all of these are wound or laminated to form a capacitor element.

(Problem to be solved by the invention) In an electrolytic capacitor using a solid electrolyte as described above,
When the anode and cathode or anode foil and cathode foil are cut to their required usage, short circuits may occur due to cutting edges that occur at the cut ends;
In addition, if the capacitor element has a structure in which the anode foil and the cathode foil are in close contact, such as a wound type or a laminated type, impregnation with TCNQ complex that generates a solid electrolyte or formation of a chemical polymer film as a base film for electrolytic polymerization is required. This was sometimes difficult due to the viscosity of the TCNQ complex used and the chemical polymerization solution.

[Structure of the Invention] (Means for Solving the Problems) The solid electrolytic capacitor according to the present invention has an electrode foil cut into required dimensions, or cut ends of an anode foil and a cathode foil that are connected to the electrode foil or anode foil. It is formed so as to be on the inner side of both sides of the cathode foil, and is constructed by winding these nine times as they are or by laminating them.

(Function) In the solid electrolytic capacitor according to the present invention, the cut Igi ends of the electrode foil or the anode foil and the cathode foil are wedge-shaped.

By forming the shape into a convex shape, approximately semicircular shape, approximately R shape, sloped shape, etc., or a combination of these shapes, the pars that occur at the cutting edge are removed from the inside of both sides of the electrode foil, anode foil, and cathode foil. They can be placed or removed to prevent short circuits. In addition, since the cut end is in the shape described above and is located on the inside of both sides, the cut end that overlaps the laminated or wound edges is cut between the foils or between the foils and the foil.
Since gaps are created in the pores and a highly viscous liquid can easily enter, the impregnation of the TCNQ complex and the formation of a chemically polymerized film can be carried out very easily.

(Example) Example 1 As shown in FIG. 1, an aluminum plate 1 with a thickness of 0.6 IM was
The surface was roughened by etching and cut into 110 m x 10 squares. At this time, the cut surface is formed so that the pars generated during cutting are hanging down from the surface. It is difficult to form a chemically polymerized film and an electrolytically polymerized film, which will be described later, on the tip of this paris, and short circuits are likely to occur between these polymeric films. The cut ends of the aluminum plate 1 cut as described above are pressed to form a wedge shape 2 as shown in the cross-sectional view in FIG.
Anode lead wire 3 was welded to. The aluminum plate 1 to which the lead wire 3 is connected in this way is subjected to chemical conversion treatment at 35V while preventing the welded portion 4 from touching the chemical liquid 5.
An anodic oxide film 6 was formed as shown in the figure.

On the anodic oxide film 6 thus produced, a chemical polymerization film 7 is first produced, and this chemical polymerization 17 is used as a ten electrode.
A single pole is placed around it and electrolytic treatment is performed to form a chemically polymerized film 7.
An electrolytic polymer film 8 was formed thereon. This electrolytic polymeric membrane 8 includes, for example, polypyrrole, and a cathode lead wire is connected to this electrolytic polymeric membrane 8 with a conductive paint, and the rated voltage is 25V.
A capacitor element of 47 μF was used. A solid electrolytic capacitor was fabricated by coating this capacitor element with a resin by a fluidized dipping method, etc. However, in this capacitor, there is no protrusion from the front and back surfaces of the aluminum plate 1, so an electrolytic polymer film is formed on the protruding protrusion. The thickness of the electropolymerization liquid 8 is also reduced, and accidents such as short circuits caused by electrolytic polymerization liquid 8 and the like peeling off and being exposed due to contact with other objects or manufacturing equipment do not occur.

Example 2 As shown in Fig. 5, a 90 μm thick high purity aluminum foil 11 with a roughened surface was cut into widths of 5 and NRX lengths of 30s+, and these cut surfaces were pressed into a convex shape 12, and the anode lead wire was Welded. After anodizing this, a capacitor element is formed by winding it with a 6# width capacitor paper and a 40μm thick x 5 width cathode foil.This capacitor element is chemically polymerized to produce polypyrrole, and this polypyrrole is then used as a cathode. And the capacitor element cathode foil is l! An electropolymerized film was formed as 12 electrodes.

In a capacitor with a rating of 25V-39μF having such a configuration, the cut surface of the aluminum foil 11 used as the anode foil is formed into a convex shape 12, so that a gap is left between the wound capacitor element and the capacitor paper. This has the advantage that the 7-mer solution for producing chemically polymerized membranes and electrolytically polymerized membranes can penetrate smoothly.

In addition, since the particles generated during cutting do not protrude from both sides of the aluminum foil 11 after being pressed to form the convex shape 12, there is no possibility of short-circuiting caused by touching the cathode foil through the capacitor paper. .

Note that in this embodiment, the aluminum foil 11 which is the anode foil
Although the case where only the cathode foil is formed into a convex shape has been described, the cathode foil may also be formed in the same way.

Example 3 The capacitor paper serving as a spacer was removed from the structure of Example 2, and a chemically polymerized film and an electrolytically polymerized film were produced between the anode foil and the cathode foil using the same method. In this embodiment as well, the end face of the wound capacitor element has a gap between the anode foil and the cathode foil, so that the liquid permeates smoothly during the formation of the polymer film.

Example 4 As shown in Figures 6 and 7, width 5 m x thickness 90
The cut surface of the aluminum foil 21 with a roughened surface of μm is pressed from the opposite side to form a slope 22, and this is folded ['! After welding the anode lead terminal 23, a chemical conversion treatment was performed to form an anodic oxide film 24. In this state, a chemically polymerized film 25 and an electrolytically polymerized film 26 are generated,
A cathode lead terminal 28 is connected to the electrolytic polymer film 26 using a conductive paint 27 to form a capacitor element.

In this configuration, the three directions of the aluminum foil 21, which is the electrode foil, are sloped, so that when producing chemically polymerized membranes or electrolytically polymerized membranes, the liquid used to generate them can penetrate smoothly and reliably. It will be held in

Note that the same effect can be obtained using a laminated type in which only aluminum foil or aluminum foil and spacers are alternately stacked.

In the above embodiments, the case of a solid electrolytic capacitor using an electrolytically polymerized membrane was described, but the present invention can also be used for a solid electrolytic capacitor using a TCNQ complex. Then, the cut end should be shaped like a tree, a convex shape, or an inclined surface, but the cut end should be in a substantially semicircular shape 32 as shown in FIG. 8, a roughly rounded shape 42 as shown in FIG. It has the same effect as long as it is formed.

As described above, in the solid electrolytic capacitor according to the present invention, the cut surfaces of the electrode foil, or the anode foil and/or the cathode foil are formed to be inside of both surfaces.
Since short circuits do not occur, and gaps are created at the end faces of the capacitor element in the wound type or laminated type, the liquid can penetrate smoothly and reliably.

[Effects of the Invention] The solid electrolytic capacitor according to the present invention can prevent short circuits due to sparks when cutting electrode foil, etc.
During the production of chemically polymerized membranes, electrolytically polymerized membranes, TCNQ complexes, etc., the gaps created between the parts allow for smooth penetration of the liquid.
Moreover, this process is carried out quickly and has the effect of reliably forming a solid electrolyte.

[Brief explanation of the drawing]

The drawings all show embodiments of the present invention, and FIG. 1 is a front sectional view showing a cut state of an aluminum plate, and FIG. 2 is a front sectional view showing a state where the cut end of an aluminum plate is formed into a wedge shape. FIG. 3 is a front sectional view showing the chemical conversion treatment state, FIG. 4 is a front sectional view showing the aluminum plate on which the electrolytically polymerized film has been formed,
Figure 5 is a front cross-sectional view showing an aluminum foil with a convex cut end, Figure 6 is a front cross-sectional view of an aluminum foil with a sloped cut end, and Figure 7 is a cross-sectional view of an aluminum foil that has been folded and laminated. The side sectional view shown, and FIGS. 8 and 9 are front sectional views showing the cut ends, respectively. 1... Aluminum plate 2... Wedge-shaped cut end 3
... Anode lead wire 4 ... Welded part 5 ... Chemical liquid 6 ... Anodic oxide film 7 ... Chemical polymer film 8 ... Electrolytic polymer film 11 ... Aluminum foil 12 ... Convex Shape 21... Aluminum foil 22.
...Slope 23...Anode lead terminal 24...Anodic oxide film 25...Chemical polymer film 26...Electrolytic polymer film 27...Conductive paint 28...Cathode lead terminal holder Applicant Marukon Electronics Co., Ltd. Figure 7 Figure 6
No. 8 Figure 9

Claims (2)

[Claims] (1) In a solid electrolytic capacitor in which a capacitor element is constructed by winding or laminating electrode foil, anode foil and cathode foil, or anode foil and cathode foil with a spacer in between,
A solid electrolytic capacitor, characterized in that the cut ends of the electrode foil, anode foil and/or cathode foil are formed inside both sides of the electrode foil, anode foil and/or cathode foil. (2) The cut ends of the electrode foil or anode foil and cathode foil are wedge-shaped,
The solid electrolytic capacitor according to claim 1, which has a convex shape, a substantially semicircular shape, a substantially rounded shape, a sloped shape, or a combination thereof.