JPS5948917A - 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 i
This invention relates to an electric double layer capacitor that utilizes an electric double layer, and is related to a small-sized, large-capacity, single-layer double-layer capacitor in which a plurality of elements made of carbon fiber and a metal spray layer are laminated. .

Conventional Structures and Problems Conventional electric double layer capacitors are roughly divided into two types based on the shape of their polarizable electrodes. The most difficult one uses activated carbon powder as a polarizable electrode, and has the following structure. That is, as shown in FIG. 1, a net-like current collector 1 such as an expanded metal made of aluminum metal is used.
On top of that, graphite.

A paste composed of carbon black, activated carbon, etc. and a binder such as tetrafluoroethylene/polyvinylpyrrolidone is rolled and supported as the polarizable electrode 2.

Then, the separator 3 impregnated with an electrolytic solution, the current collector 11 and the polarizable electrode 2 are wound, and the aluminum case 4 is shaped like 11 rows a).
It was sealed and sealed.

The second type is cloth made of activated carbon fibers.

A paper or felt material is used as the polarizable electrode 5. A current collector 6 is formed on the electrode 5 by plasma spraying, and a current collector 6 is formed on the electrode 5 through a plater 7 impregnated with an electrolytic solution. , as shown in FIG. Note that 9 in the figure is an insulator 7-lupanoking.

The latter of the above two types of electric double layer capacitors is
This invention is based on the invention of the present inventors (Japanese Unexamined Patent Publication No. 55-9971
It was realized by combining the reddening surface area, mechanical strength, and other features of activated carbon fiber M (4 bows official publication) and metal spray layer formation technology, making it possible to create an electric double layer capacitor with the size of a small dog. This is what we provide.

OBJECTS OF THE INVENTION The present invention further develops the second type described above, and provides a reliable I/C with 11 and 1'1. The purpose of this site is to provide 11th and 1st year electrician capacitors.

Structure of the Invention In the present invention, a plurality of unit capacitor elements are stacked, and a metal sprayed layer is formed on the end face of the unit capacitor element to take out the entire electrode.

Description of Examples The electric double layer capacitor of the present invention is roughly divided into the following two types:
Ru. Namely, a first type in which a unit capacitor element is a combination of two polarizable electrodes and a separator, and a second type in which a unit capacitor element is a combination of one polarizable electrode, a separator, and a non-polarizable electrode. It is different from that of the type.

Figure 3 shows the basic structure of the first type, showing the carbon fiber
Or a sheet of cloth made of activated carbon fibers, sandwiched between a metal layer 11 on felt 10 and a separator 1 impregnated with electrolyte? , let this composition A be a Jlljll intermediate Sita element. At this time, the metal layer 11 functions as a collector electrode, and the carbon fiber layer 10 functions as a polarizable electrode. These unit capacitor elements are shown in the same figure.
t'f layer, both ends B.

Metal layers 13 and 14 are provided on B' and serve as collective electrodes. At this time, it is preferable to provide insulation between adjacent unit capacitor elements A and A by using a spacer 15 or the like. There are various methods for forming the metal layers 13 and 14, but plasma spraying, arc spraying, etc. are suitable.

Figure 4 shows the second type of construction (this configuration is shown).
a metal layer 21 on top of the metal layer 21 and a separator 22 impregnated with an electrolyte
The combination B becomes a unit capacitor element. As shown in the figure, n pieces of these four unit capacitors are alternately stacked, and metal layers 23 and 24 are provided at both ends C9C, respectively, to serve as collective electrodes. In the electric double layer capacitor having such a configuration, the metal layer 21 functions as a collector electrode, and the carbon layer 2o functions as a polarizable I-electrode. The metal layers 21 facing each other with the separator 22 in between are made of carbon fibers # and f.
One layer of 200 individual ? ]
' Configure the 1st place capanta element.

These electrode configurations are realized by a combination of activated carbon fibers used as polarizable electrodes (11) and thermally sprayed fully stopped i-layers used as current collecting electrodes.

Next, the activated carbon fibers and sprayed metal layer used in the present invention will be described in detail.Activated carbon is generally used as the polarizable electrode of an electric double layer capacitor from the viewpoint of its reddening surface area and chemical stability. The activated carbon fiber used in the present invention has a specific surface area of, for example, 1000 to 2000 m7. PR activated carbon fibers are assembled into a piece of cloth or felt, and its properties are compared with conventional coconut-based granular activated carbon as shown in Table 1 below.

Margins below Among these, coconut shell-based activated carbon powder is used as the first type of powder paste polarizable electrode described above.
It has a surface layer of 00 to BOOm7gr. On the other hand,
Phenol-based, rayon-based, and acrylic activated carbons are
As shown in the figure, a method of directly carbonizing and activating raw material fibers,
There is a method of activating carbon fiber after it has been made into carbon fiber.
In either case, activated carbon fibers can be used in the form of cloth or felt. The material obtained by this method has a surface area of 1000~2ooOm7gr, which is more than double that of palm-based activated carbon powder, and if this reddened surface area can be effectively utilized, a very large capacity can be obtained in a small volume. be able to.

Furthermore, among the activated carbons such as Vζ, Kono'L, and others, acrylic and pitch types are generally somewhat flexible (applied to IJl,
The surface area of the ma/ko is a little small. The surface area of the rayon type is small, but it is a fiber. The carbon fibers are brittle and still feel like 1)3, but they are difficult to make into paper, suffer from flaking, and have problems with chemical resistance and water resistance. On the other hand, phenolic carbon fibers are made from cured novolac fibers, and since the cured novolac fibers are infusible and have low heat shrinkage, there is no need to make the raw material fibers infusible beforehand. It is particularly excellent as a polarizable electrode for electric double layer Yayapasita because it can be activated carbonized and has excellent strength and flexibility. It's a phenolic carbon fiber thread.
Paper making using 1 as the raw material fi''Il has a number of advantages, especially the use of phenolic carbon fiber as a raw material and 1'1 as a binder. The paper made by this process is extremely superior in many aspects such as flexibility, electrical resistance, +1Iil water resistance, chemical distribution properties, 1 roll strength, processing accuracy, electric crushability, cost, etc., and is superior to its competitors. It's Jt if it's acceptable to do it.

Next, the thermal sprayed metal layer will be described in detail.

The metal current collecting layer used in the present invention is plasma sprayed.

Formed by arc spraying etc.'1. /ζ is preferable 1, metal collection '11L layer and shite, for example, gold '7J4
9j! Activate (1 ton of charcoal! Sandwiched between the I and the separator, or use a metal evaporation film.

Various constituent materials are possible, such as coating with conductive paint, but all of them are short or short to -1 when considering the strength of the constituent body, chemical stability against electrolyte, man-hours during manufacturing, thickness control, cost, etc. It is. In contrast, the sprayed layers 1 and 4 are
Not only can it be formed on any surface of the activated carbon fibers, but the adhesive strength between the activated carbon fibers and the metal layer is extremely strong, and the formed metal layer acts as a reinforcing material for the activated carbon fibers. It is also possible to stack Φ-level capacitors very easily. The metals used here are Al, Zn, C
Elements that are stable to the electrolyte, such as u and Ni, are suitable.

Next, we will discuss the tonnage pole extraction section. As mentioned above, in this study, the distance L) from the end face of the collecting electrode of the capacitor group is t)'L.
There are two metal layers to take out the poles of the entire gap. (・13.14 in Figure R3, 23. in Figure 4.
'24) Which metal core layer has one core, jli, f
)'L capacitor is formed so that the quasi-pole is taken out from the same side electrode, and it is the 111th place of the next comrade.
・There is a need to form a layer so that the Yapashita electrode does not come into contact with it. In order to achieve this objective, it is preferable to form these current collecting electrodes by plasma spraying. FIG. 6 shows a state in which metal powder 32 is sprayed onto the stacked unit capacitor group 3o using a plasma spray gun 31. In this case, an insulating spacer 35 or the like as described in the explanation of FIG. 3-8 may be provided so that the electrodes 33 and 34 of adjacent unit capacitors are not electrically conductive. Only the electrodes indicated by diagonal lines in the same direction in FIG. 6 are formed so as to be in contact with the collective sprayed electrode 36.

The specific way to take out the leads is as shown in FIG. 7(a), which is a face bonding type without leads (in the same figure, 40 is the capacitor body, and 41 is the sprayed electrode). Metal lead wire 42 as shown in b)
The sprayed layer 43 is formed or held on the surface of the cavanter l~,
The type embedded in the sprayed layer 43, as shown in FIG. 7(c), is coated with silver paint, solder, etc. after the sprayed layer 44 is formed.
A possible option would be one in which the metal lead wire 46 is bonded using No. 5. They all use cases made of resin, metal, or ceramic, or by dipping them in resin.

Furthermore, as shown in FIG. 7(d), the outer case 5 is in contact with the thermal spray layer 51 via a spot-welded lead 50 or the like.
2.53 and a gasket 54 to seal it and put it in a coin-shaped or pond case.

In addition, in the same figure, 55 is an insulating spacer.

Next, more specific embodiments of the present invention will be described.

(Execution 1 row 1) Activated carbon fiber (manufactured by Nippon Kynol Co., Ltd., specific surface area 20o
An aluminum conductive layer with a thickness of 5 μm is formed on one side of the 5 μm thick aluminum conductive layer by plasma spraying.
10 sheets of fresh wood cut into a 1 nm square are stacked together with a separator as shown in FIGS. 3 and 4. However, in the present example, the separator with +4J is made of polyethylene fillo with a thickness of 10 μm, and the separator contains 30% by weight of propylene carbonate, 50% by weight of γ-fu/-rolactone, and tetramethylammo.

A solution containing 20% by weight of Nibarchlorate is impregnated as an electrolyte. Aluminum sprayed layers (thickness 1
0107l is formed and the electrodes are taken out. The multilayer capacitor thus produced was sealed into a housing by the method shown in FIG. 7(d), and its characteristics were measured.

Table 2 shows No. 1 obtained in this example. The characteristics of the electric double layer capacitor are compared with those of the conventional activated carbon powder type and the activated carbon fiber single layer type.

Table 2 As is clear from Table 2, what is the size of the bank according to the present invention? The capacity of the 1'1 position A'i A/C: 1: is always large, the internal resistance per unit capacity is small, and the capacitance change during high temperature load life is small.

Effects of the Invention As described above, the present invention utilizes activated carbon fiber assembly and metal spraying technology to realize an electric double layer capacitor that has excellent advantages such as a very large capacity per unit volume. , its industrial value is very dog.

[Brief explanation of drawings]

FIG. 1 is a diagram showing an example of a conventional electric double layer capacitor.
FIG. 2 is a diagram showing an example of a conventional 'iL double layer capacitor, FIG. 3 is a diagram showing an example of an electric double layer capacitor according to the present invention, and FIG. 4 is a diagram showing an example of an electric double layer capacitor according to the present invention. FIGS. 7(a) and 7(b) are diagrams showing an example of the method for forming the current collecting electrode. This is an example of the composition of a full-sized J-diagram. 1.6... Assembly, 2.5... Polarizable electrode, 10.20... Carbon fiber layer, 11, 13
, 14°21.23.24...metal layer, 43,
44.61...Thermal spray layer. Name of agent Benyo Ishi Toshio Nakao and one other person Figure 1 Figure 2

Claims (6)

[Claims] (1) Consisting of a pair of polarizable electrodes made of carbon fiber facing each other via a separator impregnated with an electrolytic solution, and opposite f of the pair of polarizable electrodes facing the separator.
A plurality of unit capacitor elements provided with current collectors are stacked in the lu, and electrodes for external extraction are provided on both end faces of the stack of unit capacitor elements, and a pair of unit capacitor elements provided in the unit capacitor elements are provided. An electric double layer capacitor characterized in that the current collectors are electrically connected to the external extraction electrodes. (2) Collection ILI: Body and external J1y output electrode emit plasma 6. The electric double layer capacitor according to claim 1, wherein the electric double layer capacitor is made of a metal member formed by any one of arc spraying. (3) The collector 1L body and the electrode for external extraction are made of Al and Ni. Selected from the group consisting of Zn and Cn
The electric multilayer capacitor according to claim 1, characterized in that the multilayer capacitor comprises at least one type of . (4) The electric double layer canopy according to claim 1, characterized in that the electric double layer canopy is made of activated carbon Ka and fibers in which carbon fibers are activated. (5) The electric double layer capacitor according to claim 1, wherein the carbon fiber is made of phenolic carbon fiber or activated novolac activated carbon fiber. (6) A unit capacitor consisting of a polarizable electrode made of carbon fiber, with a current collector on one side and a separator impregnated with an electrolytic solution on the other side, is arranged such that the L current collector and the separator are adjacent to each other. A plurality of unit capacitor elements are laminated in such a manner that a plurality of unit capacitor elements are laminated together, and a plurality of unit capacitor elements are laminated together. An electric double layer capacitor having a 11 Jt characteristic in which current collectors are alternately connected to external lead-out electrodes on both end faces of the laminate.