JPS5935418A - Electric double layer capacitor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an electric double layer capacitor. As shown in Figure 1, an electric double layer capacitor is made of a polarizable electrode material such as activated carbon or acetylene black along with some binder such as aluminum, tantalum, or
It has a structure in which a polarizable electrode 1.11 is supported on a current collecting plate made of a metal such as titanium that has a valve action, and these electrodes are faced to each other with a microporous separator 2 containing an electrolytic solution interposed therebetween. The electric double layer formed at the interface between the polarizable electrode and the electrolyte is used as a capacitor to form an ultra-large capacitance on the order of 100 degrees.It is used for instantaneous holding of gas safety valves, power supplies for toys, and memory backup. It is widely used.

[Prior Art and Problems] Figure 2 shows a practical structure of a polarizable electrode of an electric double layer capacitor. 3 is a current collecting plate made of valve metal, 4 is the polarizable electrode material supported on this plate, and 5 is an extraction lead wire. FIG. 3 shows a wound type electric double layer capacitor in which the polarizable electrodes shown in FIG. 2 are overlapped with a separator in between, and a capacitor element 6 formed by winding the capacitor element 6 is impregnated with an electrolyte and housed in an aluminum zoom case 7. . Note that 8 is a rubber backing and 9 is a sealing resin. FIG. 4 shows a flat plate type 1, f a greasy surface coating, and 13 an insulating ring.

By the way, as mentioned above, the conventional electric double layer capacitor has an ultra-large capacitance, but this ultra-large capacitance has a drawback that the capacitance decreases over time. The main reason for the decrease in capacity is thought to be due to vaporization of the electrolyte, and as a countermeasure, attention is being paid to improving sealing performance, but complete sealing has drawbacks in terms of workability and cost. and have not achieved sufficient results.

[Object of the Invention] The present invention is intended to solve the above-mentioned problems, and its purpose is to provide an electric double layer capacitor that exhibits little change over time, and in particular, very little decrease in capacitance over time. It is something to do.

[Structure of the invention] Opposing electric double layer capacitors? jf@1
．． are of the same shape and size.

This is because the electric double layer capacitance that exists at the interface between each electrode and the electrolyte is connected in series, and the combined capacitance is utilized, so it is best to use electrodes with the same capacity. This is because capacitance can be obtained. In addition, when using a wound type, the inner electrode and the outer electrode 14
In order to completely oppose electrode No. 11, the inner electrode is made slightly shorter.

The present invention has a structure in which first and second polarizable electrodes, in which a polarizable electrode material such as activated carbon or acetylene black is supported on a metal current collector plate having a valve action, are opposed to each other with a separator containing an electrolytic solution interposed therebetween. In the electric double layer capacitor, a third polarizable electrode having no lead wire is inserted between the opposing first and second polarizable electrodes via a separator.

[Embodiment] FIG. 5 shows the basic structure of a '4L double layer capacitor of the present invention. In the figure, 14 is a first polarizable electrode having a lead wire 18, and 15 is a second polarizable electrode having a lead wire 19.

Reference numeral 16 denotes a sixth polarizable electrode having no lead wire, and is inserted through a separator 17 between the opposing first and second polarizable electrodes 14 and 15.

This laminate of the first, second and third polarizable electrodes is put into practical use by being molded into a roll shape as shown in FIG. 6 or a flat plate shape as shown in FIG.

[Effects of the Invention] In order to confirm the effects of the present invention, l
] 13rmn first electrode with a length of 40mm, a width of 16mm,
A conventional capacitor A having the shape shown in FIG. 3, in which a second electrode having a length of 50+ra is wound through a separator, impregnated with an electrolytic solution, housed in an aluminum case, and sealed with a rubber parakink' and a handle surface; [l] between the first electrode and the second electrode
Regarding capacitor B of the present invention, which was formed in the same manner by inserting a third electrode with a length of 15 mm and a length of 40 mm,! We conducted a comparative test of subjectivity. The experiment first measured the initial capacitance, internal resistance, and leakage current for A and B at room temperature, then measured the initial capacitance, internal resistance, and leakage current for A and B.
A 2■ load life test was conducted for 1000 hours in an atmosphere of 0℃, and every 250 hours during this period, the capacitance, internal resistance, and leakage current were measured after returning to room temperature. 1111 was established. The results are shown in the table below.

As shown in the table, it can be seen that the capacitor B of the present invention is superior to the conventional capacitor A in terms of the rate of change (rate of decrease) in capacitance and the rate of increase in internal resistance.

[Brief explanation of drawings]

Figure 1: A diagram showing the basic structure of an electric double layer capacitor. Figure 2: A perspective view of a bipolarizable electrode. Figure 3: A side view of a wound type electric double layer capacitor. Figure 4:
Side view of flat plate type electric double layer capacitor Figure 4 2 A diagram showing the basic structure of the electric double layer capacitor of the present invention (A)
is a plan development view, ←) is a top view [Symbols] 1.11...Polarizable electrode, 2...Separator, 6...Current plate, 4...Polarizable electrode material, 5.・
・Output lead wire, 6... Capacitor element, 7...
・Aluminum case, 8...Rubber backing, 9
... Sealing resin, 10, j O'... Polarizability't pole, 11... Separator, 12, 12'... Travel surface coating, 13... Insulating ring, 14... No. 1 polarizability, 15... second polarizable electrode, 16... sixth polarizable electrode, 17... separator, 1 B, '19...
・Output lead wire 83-

Claims (1)

[Claims] In a structure in which first and second polarizable electrodes each having a polarizable electrode material such as activated carbon or acetylene black supported on a metal current collector plate having a valve action are opposed to each other with a separator containing an electrolyte in between. An electric double layer capacitor characterized in that a third polarizable electrode having no lead wire is inserted between opposing first and second polarizable electrodes via a separator.