JP2001237148A - Electric dipole layer capacitor and its manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the internal resistance of a capacitor element and to lower energy loss in the case of charge and discharge. SOLUTION: Both surface sides of a beltlike metallic foil 7 are coated with conductive adhesives, polarizable electrode layers 8, 9 are stuck on both surface sides of the metallic foil 7, fixed pressure is applied onto both surfaces of the metallic foil 7, and the conductive adhesives are dried and cured by drying, thus obtaining electrode bodies 6 having small contact resistance among the metallic foil 7 and the conductive adhesives and the polarizable electrode layers 8, 9.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric double-layer capacitor having a capacitor element in which a polarizable electrode layer is provided on both sides of a metal foil and having an anode and a cathode electrode wound thereon, and a method of manufacturing the same. In particular, the present invention relates to an electric double layer capacitor suitable for manufacturing an electrode body forming the capacitor element.

[0002]

2. Description of the Related Art An electric double layer capacitor is shown in FIG.
As shown in FIG. 1, a capacitor element 2 impregnated with an electrolytic solution is housed in an outer case 1 and its opening end is closed by a sealing plate 4 to which an external terminal 3 is fixed.

For the capacitor element 2, for example, a sheet-like electrode body 6 having an electrode tab 5 as shown in FIG. 3 is prepared for an anode and a cathode, and as shown in FIG. Are wound so as to overlap each other. However, FIG. 4 shows the winding of one of the anodes 6 and the cathodes 6 for convenience of explanation.

As shown in FIG. 3, the electrode body 6 is provided with polarizable electrode layers 8 and 9 on both sides of a strip-shaped metal foil 7 made of aluminum or the like. These polarizable electrodes 8, 9
Can be obtained by applying activated carbon or pasting an activated carbon sheet.

Further, the electrode tab 5 needs to be electrically connected to the metal foil 7, and the metal tab 7 is previously stitched,
The connection is made by a method such as ultrasonic welding and cold welding.

[0006]

In the electric double layer capacitor described above, it is required to reduce the internal resistance of the capacitor element obtained by winding the electrode body 6. That is, if the internal resistance of the capacitor element is large, the energy loss at the time of charging or discharging increases.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an electric double layer capacitor and an electric double layer capacitor capable of reducing the internal resistance of a capacitor element and reducing energy loss during charging and discharging. It is intended to provide a manufacturing method.

[0008]

To achieve the above object, a method for manufacturing an electric double layer capacitor according to the present invention comprises:
A first step of applying a conductive adhesive to both sides of the strip-shaped metal foil, a second step of attaching polarizable electrode layers to both sides of the metal foil, and after attaching the polarizable electrode layer. A third step of applying a constant pressure to both sides of the metal foil, and a fourth step of drying and curing the conductive adhesive by drying after applying the constant pressure. .

In this case, the metal foil has a thickness of 40 to 50 μm.
m of aluminum-etched foil, graphite paint as a conductive adhesive, and a thickness of 15 as a polarizable electrode layer.
An activated carbon sheet of 0 to 400 μm may be used, and the thickness of the polarizable electrode foil may be compressed to about 85 to 95% of the initial thickness.

Further, in the electric double layer capacitor according to the present invention, a first step of applying a conductive adhesive to both sides of the strip-shaped metal foil, and attaching a polarizable electrode layer to both sides of the metal foil. A second step, a third step of applying a constant pressure to both surfaces of the metal foil after attaching the polarizable electrode layer, and after applying the constant pressure, drying the conductive adhesive by drying. It is characterized by being obtained by a fourth step of drying and curing, using an aluminum etched foil having a thickness of 40 to 50 μm as a metal foil, using a graphite paint as a conductive adhesive, and forming a polarizable electrode layer having a thickness of 150 μm. ~ 400 μm
And the thickness of the polarizable electrode foil may be compressed to about 85 to 95% of the initial thickness.

[0011]

According to the present invention, a conductive adhesive is applied to both sides of a strip-shaped metal foil, a polarizable electrode layer is attached to both sides of the metal foil, and a certain pressure is applied to both sides of the metal foil. By drying and curing the conductive adhesive by drying, the contact resistance between the metal foil, the conductive adhesive, and the polarizable electrode layer is reduced.

[0012]

Embodiments of the present invention will be described below. In the drawings described below, FIGS.
Parts common to those in FIG. 4 are denoted by the same reference numerals.

FIG. 1 is a process chart showing an embodiment of a method for manufacturing an electric double layer capacitor according to the present invention. In FIG. 1, for convenience of explanation, the electrode tab 5 shown in FIG.
Manufacturing process is omitted.

First, as shown in FIG. 1A, a conductive adhesive such as graphite paint is applied to both sides of a strip-shaped metal foil 7 made of aluminum or the like, and then a polarizable electrode layer 8 made of an activated carbon sheet or the like is applied. , 9 are pasted.

Here, the metal foil 7 is, for example, 40 to 50.
The thickness can be about μm. The activated carbon sheets of the polarizable electrode layers 8 and 9 can have a thickness of about 150 to 400 μm.

After attaching the polarizable electrode layers 8 and 9, FIG.
As shown in (b), a constant pressure is applied from the upper and lower surfaces of the metal foil 7. Here, as a method of applying a constant pressure, a method of passing between rollers at fixed intervals can be used.

As a result, the thickness of the polarizable electrode layers 8, 9 is compressed to, for example, about 85 to 95% of the initial thickness. By applying a constant pressure from the upper and lower surfaces of the metal foil 7, the contact resistance between the metal foil 7, the conductive adhesive, and the polarizable electrode layers 8, 9 can be reduced.

By applying a certain pressure, the polarizable electrode layers 8 and 9 are compressed. In this case, since the frequency of contact between the activated carbons constituting the polarizable electrode layers 8 and 9 is increased, the electric resistance of the polarizable electrode layers 8 and 9 can be reduced.

After applying a certain pressure from the upper and lower surfaces of the metal foil 7, the conductive adhesive applied to both sides of the metal foil 7 is dried and hardened by drying as shown in FIG. 1 (c). The electrode body 6 obtained after the drying, as described in FIG.
By winding so as to overlap via a separator,
A capacitor element is obtained.

As described above, in the present embodiment, a conductive adhesive is applied to both sides of the strip-shaped metal foil 7, and the polarizable electrode layers 8 and 9 are attached to both sides of the metal foil 7. After applying a certain pressure from the upper and lower surfaces of the electrode body, the conductive adhesive is dried and hardened by drying, whereby the electrode body 6 having a small contact resistance between the metal foil 7, the conductive adhesive, and the polarizable electrode layers 8, 9 is formed. I tried to get.

Therefore, since the internal resistance of the capacitor element obtained by winding the electrode body 6 becomes small, energy loss at the time of charging and discharging can be reduced.

Further, the polarizable electrode layers 8 and 9 are compressed by a constant pressure, and the frequency of contact between the activated carbons constituting the polarizable electrode layers 8 and 9 is increased, so that the dielectric constant increases and the polarizability increases. As the capacitive reactance of the electrode layers 8 and 9 decreases, the internal resistance of the polarizable electrode layers 8 and 9 can be reduced.

Further, by winding the electrode body 6 in which the polarizable electrode layers 8 and 9 are compressed, a capacitor element having a small diameter can be obtained, and the size of the electric double layer capacitor can be reduced.

[0024]

As described above, according to the present invention,
A conductive adhesive is applied to both sides of the strip-shaped metal foil, a polarizable electrode layer is attached to both sides of the metal foil, a certain pressure is applied from the upper and lower surfaces of the metal foil, and then the conductive adhesive is dried. By drying and hardening, the contact resistance between the metal foil, the conductive adhesive, and the polarizable electrode layer is reduced. Can be.

[Brief description of the drawings]

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

FIG. 2 is a cross-sectional view showing a configuration of an electric double layer capacitor using a wound capacitor element.

FIG. 3 is a sectional view showing an electrode body forming a conventional capacitor element.

FIG. 4 is a plan view showing a capacitor element obtained by winding the electrode body of FIG. 3;

[Explanation of symbols]

 Reference Signs List 1 electrode body 2 capacitor element 5 electrode tab 6 electrode body 7 metal foil 8 polarity electrode layer 9 polarity electrode layer

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hajime Kawata 1-167-1, Higashi-Ome, Ome-shi, Tokyo Inside Nippon Chemi-Con Corporation (72) Inventor Toshikazu Takeda 8 Fujisawa City, Fujisawa City, Kanagawa Prefecture In the center

Claims (4)

[Claims] 1. A first step of applying a conductive adhesive to both sides of a strip-shaped metal foil; a second step of attaching polarizable electrode layers to both sides of the metal foil; A third step of applying a constant pressure to both surfaces of the metal foil after attaching the layer, and a fourth step of drying and curing the conductive adhesive by drying after applying the constant pressure. A method for producing an electric double layer capacitor, characterized by comprising: 2. An aluminum-etched foil having a thickness of 40 to 50 μm is used as a metal foil, a graphite paint is used as a conductive adhesive, and an activated carbon sheet having a thickness of 150 to 400 μm is used as a polarizable electrode layer. 2. The method for manufacturing an electric double layer capacitor according to claim 1, wherein the thickness of the polar electrode foil is compressed to about 85 to 95% of the initial thickness. 3. A first step of applying a conductive adhesive to both sides of a strip-shaped metal foil; a second step of attaching polarizable electrode layers to both sides of the metal foil; A third step of applying a constant pressure to both surfaces of the metal foil after the layer is attached, and a fourth step of drying and curing the conductive adhesive by drying after applying the constant pressure. An electric double-layer capacitor characterized by the above-mentioned. 4. An aluminum etched foil having a thickness of 40 to 50 μm is used as a metal foil, a graphite paint is used as a conductive adhesive, and a 150 to 40 thickness is used as a polarizable electrode layer.
4. The electric double layer capacitor according to claim 3, wherein a 0 [mu] m activated carbon sheet is used, and the thickness of the polarizable electrode foil is compressed to about 85 to 95% of the initial thickness.