JPH0319215Y2 - - 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. There are some that use

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), the bottom plate 3 is a carbon paste electrode made of active powder and an electrolyte solution (e.g. sulfuric acid aqueous solution), and 4 is an ion-permeable electrode. The non-electronically conductive porous separator 5 is a side wall made of an electrically insulating elastic material (eg rubber). The top cover 1 and bottom plate 2 serve as electrodes of the capacitor. In capacitors with this conventional structure, the withstand voltage as a capacitor is controlled by the electrolytic voltage of the electrolyte solution, so if you want to obtain a capacitor with a high withstand voltage, you can use a multilayer type capacitor in which the aforementioned capacitors are 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. If this laminate 7 remains in this state, the connection 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 having lead terminals arranged on both upper and lower surfaces of an inner case 9 made of an insulating material. was placed on the laminate 7, and then 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, the connection between the electrode located at the bottom of the laminate 7 and the first electrode plate 10 is made through the outer case 8.
Therefore, when the outer edge of the outer case 8 is caulked into a curled shape by applying pressure as shown in FIG. 4, the electrode plate 10 and the outer case 8 are
As shown in the figure, it was necessary to make mechanical contact at the end portion 10a of the electrode plate 10. For this purpose, as shown in FIG. 3, the electrode plate 10 is made to have a larger outer diameter than the interior case 9, and the connection at the end 10a of the electrode plate 10 shown in FIG. This can be done without being affected by the outer diameter of the case 9. On the other hand, in this casing structure, the electrode plate 1 before pressurizing the laminate 7
As shown in Figure 3, the position 0 often protrudes above the open end surface of the outer case 8, so if the inner case 9 shifts to the left or right with respect to the outer case 8 when applying pressure to the laminate, this will occur. Since the electrode plate 10 incorporated in the housing is also misaligned, as shown in FIG. 5, the end 10a of the electrode plate 10 and the open end surface of the outer case 8 often come into contact, resulting in buckling failure.

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

According to the present invention, there is an assembly in which 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 lead terminals 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 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 outer diameter of the first electrode plate is the outer diameter of the inner case. An electric double layer capacitor is obtained which is smaller in size and is characterized by having a tapered chamfered portion on the upper part outside the inner case.

An embodiment of the present invention will be described below with reference to FIG. As shown in FIG. 6, the first electrode plate 1
The outer diameter of the inner case 9' is made smaller than the outer diameter of the inner case 9', and a tapered chamfered part 13 is provided on the outer upper part of the inner case 9' made of an insulating material. Let's do it. According to the present invention, since the first electrode plate 10' is smaller than the outer diameter of the inner case 9', even if the inner case 9 is misaligned when pressurizing the laminate 7, the electrode plate 10' and the outer case 8 are Since the opening end surfaces do not come into contact with each other, buckling failure does not occur. Therefore, there is an advantage that production can be extremely stable, especially when the case-inserting process and the pressurizing caulking process are carried out by automatic machines.

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

[Brief explanation of the drawing]

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 sectional view showing a buckling state in a conventional casing structure. FIG. 6 is a cross-sectional view of the casing structure 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, 10,10'...(first)
Electrode plate, 11... (second) electrode plate, 12... Assembly electrode, 13... Chamfered portion.

Claims (1)

[Scope of utility model registration request] An electric laminate is an assembled electrode in which 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 an inner case made of an insulating material. In an electric double layer capacitor in which the outer edge of the conductive case is caulked into a curled shape by maintaining a predetermined pressing force, the outer diameter of the first electrode plate is smaller than the outer diameter of the inner case, An electric double layer capacitor characterized in that a tapered chamfered portion is provided on the upper part outside the inner case.