JPH03245517A - Laminated type electric double-layer capacitor - Google Patents

Abstract

PURPOSE:To reduce the contact resistance of adjacent current collectors, and to decrease the internal resistance value of a capacitor by a method wherein the contact surfaces of adjacent conductive films are dissolved using an organic solvent, and they are adhered. CONSTITUTION:The abutting outside surfaces of current-collecting plates 2 and 2 of adjacent units 10 and 10 are dissolved by applying the organic solvent such as toluene or xylene, for example, and the units are pressure-welded with each other, the organic solvent is evaporated, and they are adhered. By forming the current-collecting plates 2 of the units 10 into a laminated form by adhesion as above-mentioned, the adjacent current collectors are formed integrally with each other, and the contact resistance between them can be decreased sharply.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a multilayer electric double layer capacitor in which electric double layer capacitors each having a sintered body of activated carbon particles as polarizable electrodes are connected in series.

(Prior art) In recent years, electric double layer capacitors with large capacitance have been developed for use as backup power sources for memory in electronic devices, etc.
It is widely used and incorporated into microcomputers, IC memories, etc.

Since this type of capacitor has a low withstand voltage per unit, multiple units are connected in series to obtain a capacitor with the desired withstand voltage.Usually, units housed in metal cases are connected in series to create a laminated type capacitor. To do this, connect multiple units by pressure welding, or
As in the proposal of a laminated electric double layer capacitor shown in Japanese Patent No. 3715, units housed in a metal case are connected in series using adhesive conductive paint.

(Problems to be Solved by the Invention) As mentioned above, when electric double layer capacitor units housed in metal cases are connected in series by pressure welding, insulating oxidation occurs on the surface of the metal case during long-term use. A film will form, increasing the contact resistance between the units, and in extreme cases, there is a risk that the connection will be broken. In addition, when connecting in series using adhesive conductive paint, there are fewer problems than when using pressure welding, but since the conductive paint is interposed between the metal cases,
There is a drawback that the resistance value due to the paint increases and the input/output characteristics during lamination deteriorate.

The present invention was made in view of such problems,
The purpose is to provide a multilayer electric double layer capacitor that provides good input/output characteristics when connected in series.

(Means for Solving the Problems) According to the present invention, in a multilayer electric double layer capacitor in which units of electric double layer capacitors are connected in series, a conductive film dissolved in a predetermined solvent is used to connect the units. A multilayer electric double layer capacitor is provided in which a current collector is formed in contact with a polarizable electrode, and the contact surfaces of adjacent current collectors of stacked units are dissolved in the solvent to bond the current collectors together. be done.

(Function) In the present invention, a conductive film is used as the current collector that contacts the polarizable electrode of the electric double layer capacitor unit, and when the units are stacked, the contact surfaces of the adjacent conductive films are dissolved using a solvent. Since the adjacent current collectors are bonded together, the contact resistance between them is drastically reduced, and the internal resistance value of the multilayer electric double layer capacitor is reduced.

(Example) Next, an example of the present invention will be described in detail using the drawings.

FIG. 1 is a vertical sectional view showing one embodiment of the present invention, and FIG.
The figure is a sectional view showing the configuration of a single unit 10 of this embodiment.

In Figure 2, reference numeral 1 denotes a polarizable electrode, which is formed by applying a predetermined pressure to a powder made of activated carbon fine particles, e.g. by applying a pulsed high voltage to cause a discharge, and then holding it at a high temperature to sinter the electrode body. It is impregnated with electrolyte.

Reference numeral 2 denotes a current collector that collects the electric charge of the polarizable electrode 1. A conductive film formed by kneading conductive material powder and synthetic resin into a thin film shape is used, and one side of the electrode body is They are closely attached to minimize electrical contact resistance. Note that the synthetic resin used for kneading the current collector 2 is a material that can be dissolved in an organic solvent such as toluene or xylene, for example.

Reference numeral 3 denotes a separator, which is made of a microporous non-woven fabric made of polypropylene, etc., and is interposed between the pair of polarizable electrodes 1.1 to separate them.The outer periphery of the separator 3 is a gasket. It is buried in the middle part of the inner wall of No. 4.

The gasket 4 has a cylindrical shape made of a non-conductive synthetic resin material, has the above-mentioned separator 3 in the middle, houses a pair of polarizable electrodes 1.1 inside, and has a polarizable electrode 1.1 on the upper and lower end surfaces. The outer peripheral portions of each electric body 2.2 are closely fixed.

In the unit 10 configured in this way, by using the upper and lower current collectors 2 as both terminals, the charge possessed by the polarizable electrode 1.1 impregnated with an electrolytic solution is transferred to the current collector 2.1.
2, an electric double layer capacitor with a predetermined breakdown voltage and large capacitance can be obtained.

Next, FIG. 1 shows a structure in which, for example, three of the above-mentioned units are used, and the withstand voltage is tripled, and three units 10 are connected in series to form a stacked structure.

Then, an organic solvent such as toluene or xylene is applied to the contact surface of the current collector 2.2 of the adjacent unit 10.10 to dissolve the contacting outer surface of the current collector plate 2.2, thereby allowing the units to contact each other. The organic solvent was evaporated by pressing the two together, and the two were bonded together.

In this embodiment, the current collector plates 2 of the unit 10 are bonded to each other to form a laminated type, and since adjacent current collectors are integrated, the contact resistance between them is drastically reduced. The internal resistance of the whole unit becomes a low value.

Although the present invention has been described above using the above-mentioned embodiments, various modifications can be made within the scope of the gist of the present invention, and these modifications are not excluded from the scope of the present invention.

(Effects of the Invention) According to the present invention, when connecting electric double layer capacitor units in series to form a laminate type, adjacent contact surfaces of conductive films serving as current collectors are bonded using an organic solvent. Since the two current collectors are melted and bonded together, the contact resistance is drastically reduced, and the internal resistance of the entire laminated electric double layer capacitor becomes a low value. Therefore, a capacitor with good input pressure characteristics can be obtained. It has the effect of being

Further, according to the present invention, since a metal case is not used in the unit, there is an advantage that problems caused by the oxide film, adhesive paint, etc. can be avoided.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view showing one embodiment of the present invention, and FIG. 2 is a sectional view showing the configuration of a unit used in this embodiment. DESCRIPTION OF SYMBOLS 1... Polarizable electrode, 2... Current collector, 3... Separator, 10... Unit.

Claims (1)

[Claims] In a laminated electric double layer capacitor in which electric double layer capacitor units are connected in series, a conductive film that is dissolved in a predetermined solvent is used to form a current collector that contacts the polarizable electrodes of the units, and the laminated 1. A multilayer electric double layer capacitor, characterized in that the contact surfaces of adjacent current collectors of the unit are bonded to each other by dissolving the contact surfaces of adjacent current collectors with the solvent.