JPH0546023U - Electric double layer capacitor - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide an electric double layer capacitor which is excellent in appearance and hermeticity without sticking out of the adhesive when the current collector plate is thermocompression bonded to the gasket. [Structure] Reference numeral 12 denotes a polarizable electrode which is disposed inside a gasket 10 having a rectangular frame shape and is vertically stacked via a separator 14, and 16 denotes a gasket 1 to cover the polarizable electrode 12.
0 is a conductive film laminated on the top and bottom openings. A metal current collector plate 20 is disposed on the upper and lower surfaces of the gasket 10 via a hot melt adhesive 18, and the inside of the gasket is hermetically sealed while being pressure-bonded to the surface of the conductive film 16. Current collector plate adhering surface 10 of the gasket 10
Notches 10b are formed along the ridge lines at the inner and outer corners of a, and the adhesive spreads in a wedge shape toward the outer and inner sides of the gasket 10 in a state of being adhered to the current collector plate 20. Form a storage space.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an electric double layer capacitor which prevents the hot melt adhesive from squeezing out when the current collector plate of the electric double layer capacitor is heat fused.

[0002]

[Prior Art]

 Electric double-layer capacitors are constructed by stacking polarizable electrodes on the top and bottom of a frame-shaped gasket via a separator, and placing a conductive film on the upper and lower openings of the gasket to form a cell. It is formed by arranging a collector plate and pressing both collector plates to a gasket to hermetically seal the inside.

The electrolytic solution of the polarizable electrode contains a metal corrosive substance such as sulfuric acid, and when it leaks, not only does the current collector plate corrode, it does not function as a capacitor but also it leaks. Since the adverse effect of the electrolytic solution on other equipment is also large, leakage has been conventionally prevented by tightly sealing the seal, especially when the electric double layer capacitor is made of a single cell. The heat fusion means using is adopted. An example of such an electric double layer capacitor is disclosed in Japanese Patent Application No. 2-333427 filed by the applicant of the present application.

[0004]

[Problems to be solved by the device]

 However, when the hot melt adhesive is used, as shown in FIG. 5, when the current collector plate 2 is pressure-bonded to the gasket 1, an excess of the hot melt adhesive 3 may squeeze out to the outer peripheral portion, If this adheres to the current collector plate 2 or the like, the appearance of the product will be significantly impaired. For this reason, a step of removing the adhesive 3 that has squeezed out is required after the crimping work, and if the adhesive 3 that has squeezed out adheres to the hot plate for heat fusion, the dimensional accuracy for heat fusion decreases. However, it has been a cause of poor adhesion and a decrease in sealing performance due to this.

The present invention solves the above problems, and an object thereof is to prevent the adhesive from protruding when the current collector plate is thermocompression-bonded to the gasket, and to provide an electrical connector excellent in appearance and sealing performance. It is to provide a multilayer capacitor.

[0006]

[Means for Solving the Problems]

 In order to achieve the above object, the present invention provides a polarizable electrode that is vertically stacked inside a frame-shaped gasket via a separator, a conductive film disposed on the upper and lower opening surfaces of the gasket, and the gasket. In an electric double layer capacitor having a current collector plate that is heat-fused to the upper and lower surfaces via a hot melt adhesive and that seals the inside of the gasket in a state of being pressure-bonded to the surface of the conductive film, A notch is formed along the ridgeline at the corner of the electrical plate bonding surface.

[0007]

[Action]

 If the excess hot melt adhesive overflows due to thermocompression bonding, it flows into the space surrounded by the notch on the gasket side and the current collector plate, is held inside this space by capillary action, and solidifies by cooling.

[0008]

【Example】

 Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is a side sectional view of an electric double layer capacitor according to the present invention, in which 10 is a gasket formed in a rectangular frame shape, 12 is a gasket inside a gasket 10 and a separator 14 disposed in the middle. Polarizable electrodes 16 stacked one above the other are conductive films laminated on the top and bottom openings of the gasket 10 so as to cover the polarizable electrodes 12, and these form a basic cell. .

A metal current collector plate 20 is disposed on the upper and lower surfaces of the gasket 10 via a hot melt adhesive 18, and the inside of the gasket is hermetically sealed while being pressure-bonded to the surface of the conductive film 16. There is.

The procedure for assembling the electric double layer capacitor having the above configuration is as shown in FIG. 2, in which a film-shaped hot melt adhesive 18 cut out in a frame shape on the surface of the current collector 20 is heated. Adhesion is performed by pressurization, and then the conductive film 16 cut out in a rectangular shape is thermocompression bonded to the center of the current collector 20.

As the hot melt adhesive 18, a modified polyethylene resin such as an ethylene-vinyl acetate copolymer or an ethylene-acrylic acid copolymer is used. Further, the outer dimensions of the conductive film 16 are larger than the opening size of the hot melt adhesive 18, and the conductive film 16 is bonded in a state of overlapping the periphery of the opening.

Next, an activated carbon electrode forming the polarizable electrode 12 is thermocompression-bonded on the conductive film 16 by pressurizing and heating to form an assembly A.

By preparing two sets of this assembly A and pouring and impregnating 30% by weight sulfuric acid aqueous solution as an electrolytic solution on an activated carbon electrode, the polarizable electrodes 12 are obtained. Next, the gasket 10 is installed on the current collector plate 20 of one assembly A, the separator 14 is installed on the polarizable electrode 12, and then the current collector plate 20 of the other assembly A is installed on the upper surface of the gasket 10. Then, if hot plates (not shown) are pressed against both sides of the upper and lower sides and heated while being pressurized, the hot melt adhesive 18 is melted and solidified by subsequent cooling, and the gasket 10 and the current collector plate 20 are adhered to each other. As described above, the contents in the gasket 10 are sealed in a laminated state.

As shown in detail in FIGS. 2 and 3, notches 10b are formed along the ridges at the inner and outer corners of the current collector plate 20 adhering surface 10a of the gasket 10. In the adhesive state of this and the current collector plate 20, an adhesive accommodating space that expands in a wedge shape toward the outside and the inside of the gasket 10 is formed.

Therefore, the adhesive 18 that has overflowed from the adhesive surface by heating and pressurizing flows and fills this space, is held in the space by capillary action, and then solidifies by cooling. There is no adhesive squeeze-out as shown, and the subsequent removal process can be omitted. Further, due to the filling effect of the adhesive 18, a more reliable sealed state can be obtained as compared with the conventional case.

In the above embodiment, the notches 10b are formed on both the inner and outer sides of the gasket 10, but as shown in FIG. 4, the notches 10b are formed only at least at the outer corners where appearance problems occur. You may do so.

[0017]

[Effect of the device]

 As described in detail in each of the above embodiments, the electric double layer capacitor according to the present invention exhibits the following excellent effects.

(1) When the excess hot melt adhesive overflows due to thermocompression bonding, it flows into the space surrounded by the notch on the gasket side and the current collector plate, and is retained inside this space by the capillary phenomenon. Since it solidifies by cooling, it does not require the external appearance to be deteriorated due to the adhesive squeezing out and the time and effort to remove the squeezed adhesive are eliminated, and the sealing effect is improved by the filling effect.

(2) It is possible to prevent deterioration of the dimensional accuracy due to the protruding adhesive adhering to the hot plate and defective adhesion due to this.

[Brief description of drawings]

FIG. 1 is a side sectional view of an electric double layer capacitor according to the present invention.

FIG. 2 is an exploded perspective view of the same.

FIG. 3 is an enlarged cross-sectional view of a main part of the present invention showing a portion of FIG. 1B.

FIG. 4 is an enlarged cross-sectional view of a main part showing another embodiment.

FIG. 5 is an enlarged cross-sectional view of a main part showing a conventional example.

[Explanation of symbols]

 10 Gasket 10a Current collector adhering surface 10b Notch 12 Polarizing electrode 14 Separator 16 Conductive film 18 Hot melt adhesive 20 Current collector

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Mitsuhiro Nakamura 5 36-11 Shimbashi, Minato-ku, Tokyo Fuji Electric Chemical Co., Ltd. (72) Tatsuya Yamazaki 5 36-11 Shinbashi, Minato-ku, Tokyo Fuji Inside Electro-Chemicals Co., Ltd. (72) Inventor Kazuo Takada 5-36-11 Shimbashi, Minato-ku, Tokyo Inside Fuji Electric Kagaku Co. Within

Claims (1)

[Scope of utility model registration request] 1. A polarizable electrode which is vertically laminated inside a frame-shaped gasket with a separator interposed therebetween, a conductive film which is disposed on upper and lower opening surfaces of the gasket, and hot-melt adhesive to upper and lower surfaces of the gasket. An electric double layer capacitor, which is heat-sealed via an agent and has a current collector that seals the inside of the gasket in a state of being pressure-bonded to the surface of the conductive film, wherein a corner of a surface of the gasket on which the current collector is bonded. An electric double layer capacitor, characterized in that a notch is formed along the ridgeline in the portion.