JPS6252448B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electric double layer capacitor, and more particularly to a casing for a self-supporting electric double layer capacitor.

One method of obtaining a large-capacity capacitor using the electric double layer phenomenon is to generate an electric double layer by bringing carbon powder into contact with an electrolyte, as disclosed in U.S. Pat. No. 3,536,963. There is something that takes advantage of this.

FIG. 1 is a sectional view of an example of a conventional electric double layer capacitor.

In Figure 1, 1 and 2 are top and bottom plates made of conductive elastic material (e.g. conductive rubber), 3 is a carbon paste electrode made of activated carbon powder and an electrolyte solution (e.g. sulfuric acid aqueous solution), and 4 is an ion-permeable electrode. 5 is a side wall made of an electrically insulating elastic material (for example rubber).
The upper lid 1 and the bottom plate 2 serve as electrodes of the capacitor.

However, in electric double layer capacitors with this structure, the withstand voltage as a capacitor is controlled by the electrolysis voltage of the electrolyte solution, so if you want to obtain a capacitor with a high withstand voltage, you can use a multilayer capacitor in which the above capacitors are stacked and connected in series. It needs to be molded.

FIG. 2 is a sectional view of an example of an element laminate of a multilayer electric double layer capacitor.

In FIG. 2, 6 represents the single electric double layer capacitor (hereinafter referred to as a basic cell) shown in FIG. 1, and n represents the number of laminated basic cells required to achieve the required withstand voltage.

In the above laminated structure, the contact resistance between basic cells and the contact resistance between activated carbon particles within the basic cells becomes large, and the internal resistance becomes large as a whole. In order to prevent an increase in internal resistance, it is necessary to apply appropriate pressure to the upper and lower surfaces of the laminate and to provide a casing that maintains this pressure.

Furthermore, in the above laminated structure, since the electrodes of the capacitor appear on the top and bottom surfaces, it is extremely difficult to create a self-supporting type, that is, a shape in which two electrodes are provided on one end surface of the case. Free-standing types are commonly found in electrolytic capacitors, but in the case of electric double layer capacitors, in addition to the shape problem of two electrode surfaces appearing on opposite sides of the capacitor element, it is difficult to apply pressure. Because of the problem of applying and holding the voltage, the case of a conventional self-supporting electrolytic capacitor cannot be used as is.

In view of the above circumstances, the present invention provides a new case and casing method suitable for a self-supporting electric double layer capacitor.

According to the present invention, a pair of containers separated by an ion-permeable and non-electronically conductive porous separator are housed in a container whose side walls are made of an electrically insulating elastic material and whose top cover and bottom plate are made of a conductive elastic material. A self-supporting electric double layer capacitor in which one or more electric double layer capacitor elements filled with carbon paste electrodes and using the above-mentioned conductive top and bottom plates as electrodes are stacked and housed in a case. A first electrode plate is placed on a first electrode plate having a first electrode terminal erected on the
Insulating plates having holes through which electrode terminals pass through are stacked on top of each other, and a second electrode terminal and a first
A second electrode plate having an opening through which an electrode terminal passes through is stacked on the insulating plate and electrically insulated from the first electrode plate, and the first electrode plate is an electric double layer capacitor element laminated layer. It is electrically connected to the upper lid electrode at the top of the body, and the lower horizontal part of the electrode connection plate bent into a U-shape is electrically connected to the bottom plate electrode at the bottom of the element stack of the electric double layer capacitor. The upper horizontal portion of the electrode connecting plate is electrically connected to a second electrode plate, and the electrode connecting plate has a strip portion having corrugated folds in the center, and a strip portion having a larger width than the strip portion at both ends of the strip portion. A self-supporting electric double layer capacitor is obtained, which is characterized in that the capacitor has a section and is bent in a U-shape at the boundary between the strip section and the widening section.

The present invention will be explained below with reference to Examples.

Figures 3a to 3c are plan views (Figure a) of the manufacturing and assembly process of an electrode connection plate, which is one component of a self-supporting electric double layer capacitor case according to an embodiment of the present invention.
and perspective views (b-c figures).

FIG. 3a is a plan view of the electrode connection plate 11 when punched out from a metal plate. The size of the circular parts 12 and 13 is limited by the fact that they can fit inside the outer case, but it is advantageous to make them as large as possible in order to reduce contact resistance. The band portion 14 is provided with a large number of corrugated pleats, and the angle of the pleats changes depending on the pressure applied during assembly. The hole 15 is provided for passing one of the electrode terminals. The material may be any metal that has good workability, conductivity, and corrosion resistance.
Here we will use nickel.

FIG. 3b is a perspective view of the electrode connection plate 11 when it is bent to fit the casing.

Figure 3c shows the electrode connection plate 11 when the casing is completed.
It is a perspective view showing the shape of. When pressure is applied from above the circular part 13 during casing, the angle of the folds of the strip part 14 changes, thereby causing the circular parts 12 and 13 to change.
It will be seen that the height between

4a to 4e are perspective views of other parts necessary for the casing of an electric double layer capacitor according to one embodiment of the present invention.

Figure 4a shows a second plate made of metal such as galvanized iron.
The reinforcing plate 54 is shown. This reinforcing plate 54 is provided with holes 55, 55' through which the electrode terminals pass.

FIG. 4b shows the third insulating plate 41. FIG. Insulating plate 4
1 is provided with holes 42, 42' through which the electrode terminals pass. The material is preferably a non-brittle insulator such as polyacetal.

FIG. 4c shows the second electrode plate 31. FIG. As shown in the figure, a tab that will become an electrode terminal in the future is left, the periphery of the tab is punched out, and the tab is raised perpendicularly to the electrode plate 31 to form a second electrode terminal 32. Second electrode plate 31
The opening 33 is sized to allow the first electrode terminal 17 to pass through the second electrode plate 31 without contacting it. The material may be a metal with good conductivity, workability, and corrosion resistance. Here, we will use a nickel-plated copper plate.

FIG. 4d shows the second insulating plate 21. FIG. Insulating board 2
1 is provided with a hole 22 through which the first electrode terminal 17 passes. The material is preferably a non-brittle insulator such as polyacetal.

FIG. 4e shows the first electrode plate 16. FIG. The first electrode plate 16 is made of the same material and made in the same manner as the second electrode plate 31, but is provided so that the first electrode terminal 17 passes through the opening 33 of the second electrode plate without contacting it.

FIG. 5 is a sectional view of an electric double layer capacitor according to a first embodiment of the present invention. However, for simplicity,
A sectional view of the contents of the basic cell 6 is omitted.

A circular first insulating plate 52 made of polyacetal or the like is placed in an exterior case 51 made of metal such as galvanized iron or aluminum, and then the electrode connection plate 11 shown in FIG. 3b is placed. Then, the stack of basic cells 6 shown in FIG. 2 is inserted.
In this case, if the strength of the bottom of the exterior case 51 is weak, a metal reinforcing plate is installed between the bottom of the exterior case 51, the insulating plate 52, the electrode connection plate 11, or the lowest part of the basic cell stack. Of course, it may be inserted.

Next, a first reinforcing plate 53 made of metal is inserted, and the first electrode plate 16 and the second insulating plate 21 are sequentially stacked thereon. A desired pressure is applied from above the insulating plate 21, and the circular part 13 and the strip part 14 of the electrode connecting plate 11 are
Bend at the boundary with. Next, the second electrode plate 31 and the third insulating plate 41 are sequentially stacked on the circular part 13 of the electrode connection plate 11, and pressure is applied from above, and the upper end of the outer case 51 is bent inward while being held. Tighten and secure. Here, the circular part 13 of the electrode connection plate
is assembled between the second insulating plate 21 and the second electrode plate 31, and the electrode connection plate is intended for electrical connection between the lowest part of the element stack and the second electrode plate 31. Therefore, the second electrode plate 3
Of course, it can also be assembled by being sandwiched between the upper part of the first electrode plate 31, that is, the second electrode plate 31, and the metal reinforcing plate 54. However, in this case, the upper horizontal part 13 of the electrode connection plate has a hole 15 through which the first electrode terminal 17 passes.
In addition, a second electrode terminal 3 as shown in FIG.
Of course, it is necessary to open a hole 150 through which 2 passes. Further, the metal reinforcing plate 54 may be omitted if other parts have sufficient strength. Furthermore, it is preferable to weld the second electrode plate 31 and the circular part 13 of the electrode connection plate 11, as well as other parts where metals come into contact, in order to reduce contact resistance.

With this structure, the electrode of the capacitor on the bottom surface can be moved to the top.
Can be easily made freestanding.

In order to ensure electrical insulation between the outer case 51 and the electrode connection plate 11, it is preferable to line the inner wall of the outer case 51 with a resin. The band portion 14 of the electrode connection plate 11 may be covered with an insulator such as rubber or resin.

FIG. 6 is a sectional view of an electric double layer capacitor according to a second embodiment of the present invention. However, for simplicity, a sectional view of the contents of the basic cell 6 is omitted.

This embodiment is a case where electrical insulation between the outer case 51 and the second electrode terminal 32 is not required. Therefore, the first insulating plate 52, the third insulating plate 4
Excluding 1. Manufacturing costs can be reduced by this amount. Further, the reinforcing plate 54 may be omitted if other parts have sufficient strength. As in the first embodiment, it is preferable to weld the second electrode plate 31 and the electrode connection plate 11 together.

The electrode connection plate of the present invention can be modified in various ways.

FIGS. 7a to 7d show an electrode connection plate 13 according to the present invention.
1 to 134 and a plan view of a modification of holes 151 to 154. FIG.

It will be clear that many variations are possible in addition to those shown here.

As explained in the above embodiment, the electrode connection plate 11
By providing wave-shaped pleats in the band-shaped portion 14,
During assembly, bend the circular part 13 and place the second electrode plate 31, third insulating plate 41, and second reinforcing plate 54 thereon.
This has the effect of making it easier to assemble the case by applying pressure after stacking them, caulking them at the upper end of the case, and maintaining the pressure applied state.

Although all of the above embodiments have been described in the case of a circular shape, it is clear that the same can be implemented in the case of a rectangular shape as well.

As explained in detail above, according to the present invention, a self-supporting electric double layer capacitor can be easily realized.
Furthermore, since the pressure is maintained stably, an electric double layer capacitor with good characteristics in which the internal resistance is kept at a minimum can be obtained, which is extremely effective.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of an example of a basic cell of a conventional electric double layer capacitor. FIG. 2 is a sectional view of an example of a multilayer electric double layer capacitor element laminate. Figure 3 a~
c is a plan view (a figure) and a perspective view (b to c figures) of the manufacturing and assembly process of an electrode connection plate which is one component of a self-supporting electric double layer capacitor case according to an embodiment of the present invention. FIGS. 4a to 4e are perspective views of other parts necessary for the casing of an electric double layer capacitor according to an embodiment of the present invention. FIG. 5 is a sectional view of an electric double layer capacitor according to a first embodiment of the present invention. FIG. 6 is a sectional view of an electric double layer capacitor according to a second embodiment of the present invention. FIGS. 7a to 7d are plan views of modified examples of the electrode connection plate according to the present invention. 8a to 8c are a plan view (a) and a perspective view (b to c) of the manufacturing and assembly process of an electrode connection plate, which is one component of a self-supporting electric double layer capacitor case according to an embodiment of the present invention. ). DESCRIPTION OF SYMBOLS 1... Top lid, 2... Bottom plate, 3... Carbon paste electrode, 4... Porous separator, 5... Side wall, 6... Basic cell, 11... Electrode connection plate, 12, 13... Circular part, 14... Band-shaped part, 15... hole, 16...first electrode plate, 17...first electrode terminal, 21...second insulating plate, 22...hole, 31...second electrode plate, 32...second
electrode terminal, 33...opening, 41...third insulating plate, 42, 42'...hole, 51...exterior case, 52
...first insulating plate, 53...first reinforcing plate, 54...second reinforcing plate, 55, 55'...hole. 131,13
2,133,134...Upper horizontal part, 151,15
2,153...notch part, 150,154...hole.

Claims (1)

[Scope of Claims] 1. A self-supporting electric double layer capacitor in which one or more electric double layer capacitor elements are laminated and housed in a case, the first electrode terminal having a first electrode terminal standing approximately perpendicular to the conductive plate. An insulating plate having a hole through which the first electrode terminal passes is stacked on top of the first electrode plate, and a second electrode terminal standing approximately perpendicular to the conductive plate and an opening through which the first electrode terminal passes through. A second electrode plate having a top electrode of the electric double layer capacitor is stacked above the insulating plate to be electrically insulated from the first electrode plate, and the first electrode plate is electrically insulated from the top electrode of the electric double layer capacitor. The lower horizontal part of the electrode connecting plate bent into a U-shape is electrically connected to the lowermost electrode of the electric double layer capacitor, and the upper horizontal part of the electrode connecting plate is connected to the second electrode connecting plate. The electrode connection plate is electrically connected to an electrode plate, and the electrode connection plate has a band-like part having wave-shaped folds in the center, and a widening part larger than the band-like part at both ends of the belt-like part, and the belt-like part and the widening part A self-supporting electric double layer capacitor characterized by being bent in a U-shape at the boundary between the two. 2. The self-supporting electric double layer capacitor according to claim 1, wherein a notch or an opening is provided in an upper horizontal portion of the electrode connection plate. 3. The electric double layer capacitor element housed in the case is held by applying pressure to the electric double layer capacitor element by bending the upper end of the case inward and caulking it. Free-standing electric double layer capacitor.