JP2958534B2 - Manufacturing method of electric double layer capacitor - Google Patents

Abstract

PURPOSE:To prevent leakage of electrolyte even though a part of a current collecting plate is damaged by bonding under fusion a protective plate consisting of a carbon sheet to the outside surface of the current collecting plate which corresponds to an electrode compact. CONSTITUTION:In thermo-fusion bonding of an electrode compact 1 and a current collecting plate 2, a carbon sheet 3 acting as a protective plate which has conductivity at opposite surfaces of the electrode compact 1 is disposed so that it sandwiches the current collecting plate 2. Being placed between upper and lower plates 11 and 12 of a thermo-presser, the carbon sheet is pressurized and heated and then is made to enter on one side of the current collecting plate and its fusion-bonding is performed. In this way, for example, even if a thin-walled part takes place in the thickness of the current collecting plate 2 because of the inferior surface-accuracy of the electrode compact 1, the place 2 hardly ever makes a hole. Further, if a pin hole and the like appear in the current collecting plate 2, they are protected by the carbon sheet 3 and leakage of electrolyte in a gasket 5 is thus prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention is to manufacture an electric double layer capacitor which reinforces a current collector serving as an external terminal of the electric double layer capacitor and prevents the electrolyte solution from flowing out. About the method.

(Prior art) In recent years, electric double-layer capacitors that use the electric double-layer principle and provide large capacitance have been adopted as backup power supplies for microcomputers and IC memories. Electric double-layer capacitors having a large capacitance, such as those used up to a part, have also been developed.

And as this kind of electric double layer capacitor,
In Japanese Patent Application No. 232243, a current collector made of a conductive material in which conductive fine particles are mixed with a base material is adhered to a sintered porous carbon fine particle electrolyte, and a part of the current collector is made porous. A proposal has been made by the present applicant to make invasive contact with a non-conductive electrode body.

(Problems to be Solved by the Invention) In the proposal in the above-mentioned patent application, the contact between the current collector and the electrode body becomes tight, and the internal resistance as an electric double layer capacitor decreases.

However, as shown in FIG. 4, in the contact between the electrode body and the current collector, if the surface accuracy of the electrode body is poor, the thickness of the current collector in the portion A shown in the drawing is reduced, and the hole is elongated due to elongation or deformation. There is a possibility that it will end up.

Also, as shown in FIG. 5, even if the mutual surfaces are kept parallel, if a foreign substance is mixed into the current collector or a pinhole is generated,
As described above, there is a problem that a hole is formed in the portion B and the internal electrolyte leaks.

The present invention has been made in view of such a problem, and an object of the present invention is to provide a method for manufacturing an electric double layer capacitor that prevents leakage of an internal electrolyte even if a part of a current collector plate is damaged. Is to do.

(Means for Solving the Problems) In order to achieve the above-mentioned object, according to the present invention, there is provided an electric power unit provided with a current collector plate which collects electric charges by being fused to an electrode body impregnated with an electrolytic solution. In a multilayer capacitor, a method for manufacturing an electric double layer capacitor in which a protective plate having conductivity is arranged on the outer surface of the current collector plate and the protective plate is simultaneously thermally fused when the electrode body and the current collector plate are fused. Provided.

(Operation) In the present invention, since the protective plate made of a carbon sheet is fused to the outer surface of the current collector plate corresponding to the electrode body, leakage of the electrolyte is prevented even if a part of the current collector plate is damaged.

Example Next, an example of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a sectional view showing an embodiment of an electric double layer capacitor manufactured by a manufacturing method according to the present invention.

In the figure, reference numeral 1 denotes an electrode body, which is formed by sintering activated carbon powder having a large surface area and having a predetermined particle size to be porous, and impregnating an electrolyte such as dilute sulfuric acid into a polarizable electrode. is there.

Reference numeral 2 denotes a current collector, which is formed, for example, by kneading carbon and a rubber-based material to form a flexible conductive sheet. To collect the electric charge of

Reference numeral 3 denotes a conductive carbon sheet serving as a protective plate, and when the above-mentioned electrode body 1 and the collecting electrode 2 are thermally fused,
A carbon sheet 3 is provided on the opposite surface of the electrode body 1 with the current collector 2 therebetween.
2 and placed between the upper plate 11 and the lower plate 12 of the hot press as shown in FIG. 2 to apply pressure and heat, and enter one side of the current collector plate 2 as shown in FIG. And heat-sealed.

In FIG. 1, reference numeral 4 denotes a separator, which is formed by impregnating a microporous film made of polypropylene or the like with an electrolyte, and a pair of electrode bodies 1, 1 containing the electrolyte.
Is to be separated.

Reference numeral 5 denotes a gasket, which is a cylindrical member made of a non-conductive synthetic resin material, and has a middle portion in which an outer edge portion of the separator 4 is buried, and a pair of electrode bodies 1 separated by the separator 4. It is for storing 1.

The outer peripheral portions of the current collector plate 2 to which the electrode body 1 and the carbon sheet 3 are fused are fused to both end surfaces of the gasket 5, respectively, to seal the electrode body 1 containing the electrolyte therein. .

In the present embodiment thus configured, the current collector 2
Since a carbon sheet 3 serving as a protective plate is fused to the outer surface of the current collector plate 2, it is difficult to form a hole even if the current collector plate 2 has a thin portion due to poor surface accuracy of the electrode body 1. Even if the current collector plate 2 has a pinhole or the like, it is protected by the carbon sheet 3 so that leakage of the electrolyte into the gasket 5 is prevented.

As described above, the present invention has been described by the above embodiment, but within the scope of the present invention, for example, instead of using a carbon sheet to be fused to the current collector plate, using a metal plate that is not easily affected by the electrolytic solution, Various modifications are possible and do not exclude these modifications from the scope of the present invention.

(Effects of the Invention) As described above, according to the present invention, the current collector plate to be fused to the electrode body containing the electrolytic solution is provided with a carbon sheet, and the current collector plate is backed and protected. Even if the current collector plate has a thin part due to poor surface accuracy of the body, or if there is a defect such as a pinhole, a defect that a hole is formed and the internal electrolyte leaks can be prevented. .

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing an embodiment of an electric double layer capacitor manufactured by the manufacturing method according to the present invention, FIG. 2 is an explanatory view of a case where the capacitor is arranged in a hot press machine, and FIG. FIGS. 4 and 5 are explanatory views of a conventional state. 1 ... electrode body, 2 ... current collector plate, 3 ... carbon sheet,
4 ... separator, 5 ... gasket.

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Seiichi Kito 8 Fujisawa City, Kanagawa Prefecture, Isawa Motor Corporation Fujisawa Plant (72) Inventor Noriaki Niida 8 Isuzu Engineering, Fujisawa City, Kanagawa Prefecture Inside the Ring Co., Ltd. (72) Inventor Fumio Nakanishi, 8 Tsuzura, Fujisawa, Kanagawa Prefecture Inside the Isuzu Motor Co., Ltd. Fujisawa Plant (72) Inventor Hiroyoshi Moroboshi, 8 Tsuzura, Fujisawa City, Kanagawa Prefecture, Isuzu Motors Fujisawa Plant (72) Inventor: Kiyoshi Toshima, 8 Tsuchiya, Fujisawa, Kanagawa Prefecture, Isuzu Motors Corporation, Fujisawa Plant (72) Inventor: Masanori Nakanishi 5-36-11, Shimbashi, Minato-ku, Tokyo Fuji Electric Chemical Co., Ltd. 72) Inventor Mitsuhiro Nakamura 5-36-11 Shimbashi, Minato-ku, Tokyo Inside Fuji Electric Chemical Co., Ltd. (56) References JP-A-3-18 8368 (JP, A) JP-A-63-181412 (JP, A) JP-A-64-12511 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) H01G 9/016 H01G 9 / 155

Claims (2)

(57) [Claims] 1. An electric double-layer capacitor having a current collecting plate which collects electric charges by being fused to an electrode body impregnated with an electrolytic solution, wherein a protective plate having conductivity is arranged on an outer surface of the current collecting plate. And a method of manufacturing the electric double layer capacitor, wherein the protection plate is thermally fused at the same time when the electrode body and the current collector plate are fused. 2. The method for manufacturing an electric double layer capacitor according to claim 1, wherein said protection plate is a carbon sheet.