JPH0410684Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an electric double layer capacitor, and particularly to a casing structure.

As disclosed in U.S. Pat. No. 3,536,963, one method of obtaining a large capacity capacitor by utilizing the electric double layer phenomenon is to generate an electric double layer by bringing carbon powder into contact with an electrolyte. This is what was used.

FIG. 1 is a sectional view of an example of a conventional electric double layer capacitor (hereinafter referred to as a capacitor).

In Fig. 1, 1 and 2 are made of a conductive elastic material (e.g., conductive rubber), and the bottom plate 3 is a carbon paste made of activated carbon powder and an electrolytic chamber solution (e.g., sulfuric acid aqueous solution).The electrode 4 is ion-permeable. The non-electronically conductive porous separator 5 is a side wall made of an electrically insulating elastic material (for example, rubber).

The top cover 1 and bottom plate 2 serve as electrodes of the capacitor. In a capacitor with such a conventional structure, the withstand voltage as a capacitor is controlled by the electrolysis voltage of electrolyte dissolution, so if you want to obtain a capacitor with a high withstand voltage, you should use a multilayer type capacitor that is stacked and connected in series. It is necessary to

FIG. 2 is a sectional view of an example of this multilayer capacitor 7 (hereinafter referred to as a multilayer body). In FIG. 2, 6 represents the single capacitor (hereinafter referred to as an element) shown in FIG. 1, and n represents the number of laminated elements 6 required to achieve the required withstand voltage. In this laminate 7, in this state, the contact resistance between the elements 6 and the contact resistance between the activated carbon particles in the elements 6 are large, so apply appropriate pressure to the upper and lower surfaces of the laminate, especially the portion of the carbon paste electrode 3. It is necessary to apply pressure and create a casing to maintain that pressure. As a casing structure that satisfies these requirements, a structure as shown in FIG. 3 has conventionally been adopted. That is, an assembled electrode 12 includes a laminate 7 housed in a metallic exterior case 8, and a first electrode plate 10 and a second electrode plate 11 each having a lead terminal on the upper and lower surfaces of an inner case 9 made of an insulating material. cover the laminate 7,
Thereafter, a structure was adopted in which a predetermined pressure was applied and the outer edge of the outer case 8 was crimped into a curled shape as shown in FIG. 4 to maintain the pressure. In such a casing structure, when pressure is applied, the laminate 7 deforms inside the interior case 9 so that it is compressed in the height direction and expanded in the lateral direction, as shown in FIG.

In order to reasonably generate this lateral expansion, the laminate 7 needs to be located approximately at the center of the interior case 9 before pressurization, but in the conventional structure shown in FIG. Since the laminate 7 can be moved to any desired position inside the laminate 7, when pressure is applied, the pressure distribution may become uneven or the shape may become defective.

The object of the present invention is to eliminate such drawbacks.

According to the present invention, an electric double layer capacitor element laminate is housed in a conductive case, and a first electrode plate and a second electrode plate each having a lead terminal are arranged on the upper and lower surfaces of the inner case made of an insulating material. In an electric double layer capacitor in which an assembled electrode is placed over the laminate and the outer edge of the conductive case is caulked into a curled shape by maintaining a predetermined pressing force, the tapered inclined portion provided at the upper part of the inner case is An electric double layer capacitor characterized in that the slope is larger than the lower part inside the case is obtained.

One embodiment will be described below with reference to FIG.
FIG. 5 shows an inner case 9' made of insulating material as shown.
The void created after pressurizing the inner upper part (1 in Figure 4)
Tapered part 1 having the same or smaller wall thickness as 3)
4, and the casing is carried out in the same manner as the conventional means.

According to the present invention, the laminate 7 is arranged along the tapered portion 14 of the interior case 9', so the above-mentioned drawbacks are eliminated. In addition, this invention has the advantage that positioning can be done extremely smoothly when the work of placing cases before pressurization is carried out on a production line equipped with a vibration system (such as various vibration feeders) as seen on ordinary production lines. be. Furthermore, since the slope of the tapered inclined portion is larger at the upper part than at the lower part, there is an advantage that the volumetric efficiency after casing is improved.

As mentioned above, the present invention has excellent industrial value.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing an example of an electric double layer capacitor element. FIG. 2 is a sectional view showing an example of a capacitor in which the elements shown in FIG. 1 are stacked. FIG. 3 is a sectional view of a conventional casing structure before pressurization. FIG. 4 is a sectional view showing the state of the conventional casing structure after pressurization. FIG. 5 is a cross-sectional view of the casing structure of the electric double layer capacitor according to the present invention before pressurization. DESCRIPTION OF SYMBOLS 1... Top lid, 2... Bottom plate, 3... Carbon paste electrode, 4... Porous separator, 5... Electrically insulating elastic body, 6... (Capacitor) element, 7...
...Multilayer capacitor, 8...Exterior case, 9,9'
...inner case, 10 ... (first) electrode plate, 1
1...(second) electrode plate, 12...assembly electrode, 1
3...Gap portion, 14...Tapered portion.

Claims (1)

[Scope of utility model registration request] The electric double layer capacitor element laminate is housed in a conductive case, and a first electrode plate, a second electrode plate, and a second electrode plate each having a lead terminal are arranged on the upper and lower surfaces of the inner case made of an insulating material. In the electric double layer capacitor, the assembled electrode is placed on the laminate and the outer edge of the conductive case is caulked into a curled shape by maintaining a predetermined pressure. An electric double layer capacitor characterized in that the slope of the lower part of the capacitor is larger than that of the lower part of the case.