JP3578632B2 - Electric double layer capacitor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electric double layer capacitor, whose ESR(equivalent series resistance) is low and which is durable to a large current and is easily connected in series. SOLUTION: A capacitor element 12, wherein a plurality of the positive electrode lead-out leads 18 are led out from end and a plurality of the negative electrode lead-out leads 19 are led out from another end, is accommodated into a cylindrical metal case 11, whose opinions at the upper and lower ends are sealed by insulating sealing bodies 13 and 14. A plurality of electrodes 15 and 16 are provided at every sealing body so that the plurality of electrodes can penetrate the sealing bodies. Metal conductive plates 20 and 21 are laid out and fixed respectively at the sides facing the capacitor element inside of the every sealing bodies so that the inner ends of the terminals which penetrate the sealing bodies can be connected mutually. The positive lead-out leads 18 and the negative lead-out leads 19 are connected to the inner ends of terminals 15 and 16, which are close to the lead-out leads.

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an electric double layer capacitor.
[0002]
[Prior art]
The electric double layer capacitor is a metal plate or mesh having a capacitor element, that is, a polarizable electrode formed into a sheet by kneading activated carbon, carbon and a binder, with a lead drawn in advance using a conductive adhesive. After forming an electrode body by adhering to a current collector, a capacitor element in which a pair of this electrode body was wound as an anode side electrode body and a cathode side electrode body through a separator was impregnated with an electrolytic solution. Like the electric double layer capacitor A shown, the capacitor element 1 is placed in a bottomed cylindrical metal case 2 and is connected to a lead 3 connected to an anode electrode body of the capacitor element 1 and a cathode electrode body. After the connected lead 4 is fixed to the inner ends of the anode terminal 6 and the cathode terminal 7 attached so as to penetrate the insulating sealing member 5, the upper opening of the metal case 2 is closed. Sealed with There. In FIG. 8, reference numeral 8 denotes a tape wound around the outer circumference of the capacitor element 1 to prevent the wound capacitor element 1 from rewinding, and 9 denotes an explosion-proof valve.
[0003]
[Problems to be solved by the invention]
Electric double layer capacitor, in particular an electric double layer capacitor for large current, respectively, from the anode side electrode member and the cathode side electrode member 2 by one drawn lead 3,4 as shown in FIG. 8 is withdrawn, the upper metal case 2 Are connected to the anode terminal 6 and the cathode terminal 7 arranged in the sealing body 5 of the above, but have a drawback that the equivalent series resistance (ESR) is large.
[0004]
To reduce the equivalent series resistance, the number of lead-out leads should be further increased. However, if many lead-out leads are connected to one terminal, it is necessary to endure a large current in terms of connection reliability and heat generation. It was difficult to connect to. Further, since the area of the well sealing member as trying to increase the number of terminals is limited, it is difficult to increase or to the, very to become that the anode and cathode terminals approach each other even increased if It is a danger.
[0005]
Further, since the electric double layer capacitor has a low withstand voltage, it is necessary to use the electric double layer capacitor in series connection when a high withstand voltage is required. However, the conventional electric double layer capacitor is difficult to connect in series.
[0006]
SUMMARY OF THE INVENTION An object of the present invention is to provide an electric double layer capacitor which can achieve a low ESR, withstand a large current, and is easily connected in series.
[0007]
[Means for Solving the Problems]
Electric double layer capacitor of the present invention, one upper and lower ends open at the anode side, the other becomes the cathode side, in the respective cylindrical metal casing having an opening is Rimitsu sealed by the insulating sealing member Capacitor elements from which a plurality of anode lead-out leads are pulled out from an end near the anode-side sealing body and a plurality of cathode-side drawing leads are pulled out from an end near the cathode-side sealing body are housed. Metal conductive plates are arranged and fixed respectively on the side facing the capacitor element inside the body, a plurality of anode terminals are arranged on the anode side sealing body, and a plurality of cathode terminals are arranged on the cathode side sealing body, respectively. A plurality of terminals provided on the sealing body penetrate the sealing body and the metal conductive plate, respectively, and each of the terminals is connected to the metal conductive plate, and each terminal is connected to the metal conductive plate, and a plurality of terminals pulled out from the capacitor element. Anode side Wherein the cathode side of the drawer leads are connected to the inner end of the plurality of the anode terminal or the cathode terminal dispersed.
[0008]
In addition, at least one of the metal conductive plates has a round rod-shaped element fixing rod which is partially inserted into the center of the capacitor element and holds and fixes the capacitor element .
[0009]
Further, the element fixing rod having one end fixed to one side of the sealing body penetrates the metal conducting plate so as not to contact the metal conducting plate, and the other end is connected to the sealing body on the other side through the center of the capacitor element. It may be made to be.
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
In FIG. 1, an electric double layer capacitor 10 of the present invention has a capacitor element 12 housed in an aluminum cylindrical metal case 11 having upper and lower ends opened. Openings at the upper and lower ends of the metal case 11 are made of Bakelite. It is sealed by insulating sealing members 13 and 14. Rubber packings 13a and 14a are arranged at locations where the edges 11a of the upper and lower openings of the metal case 11 and the sealing members 13 and 14 are in contact with each other in order to enhance sealing performance. Although the sealing members 13 and 14 made of bakelite are used as the sealing members, other materials, for example, the entire sealing members may be made of rubber.
[0012]
Two screw-type anode terminals 15 (15a, 15b) are arranged on the upper sealing body 13, and two screw-type cathode terminals 16 (16a, 16b) are also arranged on the lower sealing body 14, and the anode terminal 15a , 15b and the cathode terminals 16a, 16b are formed with internal screws (not shown), respectively. An explosion-proof valve 17 made of synthetic resin is provided on the upper sealing body 13, and a similar explosion-proof valve 17 (FIG. 2) is provided on the lower sealing body 14.
[0013]
The capacitor element 12 is formed by kneading activated carbon, carbon, and polytetrafluoroethylene (PTFE) as a binder into a sheet-shaped polarizable electrode (for example, having a thickness of 400 to 800 μm). (a thickness of 20 to 100 [mu] m) the Tona Ru collector pair of anode electrode member and the cathode electrode body formed adhered on both surfaces of, winding electrolytic solution via a separator made of paper or glass mixed paper Is impregnated. A tape 12a is wound to prevent rewinding.
[0014]
Four lead-out leads 18 and 19 are fixed to the anode-side electrode body and the cathode-side electrode body of the capacitor element 12, respectively, and two lead-out leads 18 and 19 are respectively connected to the anode terminals 15a and 15b and the cathode terminals 16a and 16a. 16b are fixed to the inner ends thereof by caulking, ultrasonic welding, or the like.
[0015]
Metal conductive plates 20 and 21 made of aluminum are arranged inside the sealing bodies 13 and 14 facing the capacitor element 12, respectively, and the metal conductive plate 21 (the metal conductive plate 20 has the same structure) when the cathode side is taken as an example. 2, the inner ends of the cathode terminals 16a and 16b penetrate and protrude as shown in FIG. Note that the cathode terminals 16a and 16b and the metal conductive plate 21 may be formed integrally. At the center of the metal conductive plate 21, an element fixing rod 22 is provided integrally with the metal conductive plate 21.
[0016]
The shape of the metal conductive plates 20 and 21 is not limited to the oval shape, and may be any shape such as a circle as shown in FIG. In the metal conductive plate 21 shown in FIG. 3, holes 21a and 21b are provided at locations corresponding to the element fixing rod 22 and the explosion-proof valve 17. The element fixing bar 22 may be fixed to the sealing body 14 as in the case of FIG. 3 and may not be in contact with the metal conductive plate 21.
[0017]
The element fixing rod 22 is inserted into a gap surrounded by a separator which is generally formed at the beginning of the winding of the separator at the center of the capacitor element 12, but the element fixing rod is easily inserted. The cavity may be specially formed.
[0018]
The shape of the element fixing rod 22 may be a circular rod, a conical shape capable of supporting the capacitor element 12 as shown at 22a in FIG. 4, or a conical shape from the middle of the round bar as shown at 22b in FIG. . In addition, various shapes can be used, such as a round bar shape having a supporting horizontal bar 22d in the middle as shown in FIG. 6 at 22c.
[0019]
Although the element fixing rod 22 is provided with a short one in both the lower and upper sealing plates in FIGS. 1 to 3, it is short only in the lower or upper sealing body or the metal conductive plate, or in the other metal conductive plate. A long element fixing rod extending to the vicinity of the plate may be provided. Further, as shown in FIG. 7, for example, the lower part of the element fixing bar 22 f may be fixed to the lower sealing plate 14, and the upper end thereof may be connected to the sealing body 13 through the center of the capacitor element 12. In this case, the element fixing rod 22f is configured not to contact the metal conductive plates 20 and 21.
[0020]
In the electric double layer capacitor of the present invention, three or four or more lead wires on the anode side and the cathode side may be provided, respectively, and the number of terminals may be provided on two or more pieces per one sealing body. . In order to connect a plurality of electric double layer capacitors in series, a threaded socket is provided in each of the screw terminals to be connected, for example, and a female screw jack is fitted in each of the other screw terminals in the socket. Is preferably provided by screwing. Further, the terminals are not limited to the screw type terminals, and other types of terminals such as lug terminals and lead terminals may be used.
[0021]
When the use of the electric double layer capacitor is not specified, it is preferable to provide the explosion-proof valve in both of the sealing bodies, but it may be provided in only one of them. When the explosion-proof valves are provided on both sealing bodies, they may be provided on the same vertical axis or may be provided shifted.
[0022]
The electric double layer capacitor of the present invention can be applied not only to the above-mentioned wound electric double layer capacitor but also to a multilayer electric double layer capacitor in which strip-shaped polarizable electrodes and separators are laminated in multiple layers.
[0023]
【Example】
<Example 1>
Metal bowl as shown in Figure 1 - scan of the opening of the upper and lower ends and sealed with sealing member, drawn from the respective re - structure began can pull the de electric double layer capacitor (2.3V4000F, diameter 89 mm, height 150mm )created. Aluminum was used for the metal case , metal conductive plate and element fixing rod. For the capacitor element, a polarizable electrode (thickness: 400 μm) formed into a sheet by kneading activated carbon, carbon, and polytetrafluoroethylene (PTFE) was electrically surfaced in advance using a commercially available conductive adhesive. A pair of anode-side electrode body and cathode-side electrode body , each of which is attached to both sides of a current collector made of aluminum foil (thickness: 50 μm) to which a lead lead made of aluminum is fixed by etching, are made of manila paper. It was wound with a separator interposed therebetween, and used was one in which propylene carbonate was impregnated with a non-aqueous electrolyte in which tetraethylammonium tetrafluoroborate was dissolved. Four lead wires were drawn from the anode electrode body and the cathode electrode body, respectively.
[0024]
<Comparative example>
Using the same capacitor element and electrolytic solution as in Example 1, an electric double layer capacitor (same rating and size) as shown in FIG. 8 was placed in a bottomed cylindrical aluminum case. Two lead wires were drawn from the anode electrode body and the cathode electrode body, respectively.
[0025]
The equivalent series resistance (1 KHz) was measured using the electric double layer capacitors of Example 1 and Comparative Example. As a result, the equivalent series resistance of the electric double layer capacitor of the first embodiment is 5 mΩ, while the equivalent series resistance of the electric double layer capacitor of the comparative example is 10 mΩ. The equivalent series resistance was reduced to half compared with the conventional electric double layer capacitor (comparative example).
[0026]
【The invention's effect】
In the electric double-layer capacitor of the present invention, the number of lead leads is large, the leads are dispersed and connected to the terminals, and the terminals are connected to each other by the metal conductive plate, so that the ESR (equivalent series resistance) can be reduced. Thus, an electric double layer capacitor that can withstand a large current is obtained.
[0027]
Further, in the electric double layer capacitor of the present invention, since the anode terminal and the cathode terminal are arranged vertically, they are arranged in the vertical direction, so that they can be easily connected in series and have a high breakdown voltage. Furthermore, since the drawer lead and the anode terminal and the cathode terminal are completely separated from each other, there is no danger of contact between the drawer lead and the external conductor.
[Brief description of the drawings]
FIG. 1 is a sectional view of an electric double layer capacitor according to the present invention.
FIG. 2 is a diagram showing a metal conductive plate inside a sealing body.
FIG. 3 is a diagram showing another metal conductive plate.
FIG. 4 is a view showing an element fixing rod.
FIG. 5 is a diagram showing another element fixing rod.
FIG. 6 is a view showing another element fixing rod.
FIG. 7 is a view showing another element fixing rod.
FIG. 8 is a sectional view of a conventional electric double layer capacitor.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Electric double layer capacitor 11 Metal case 12 Capacitor element 13 Sealing body 14 Sealing body 15 Anode terminal 16 Cathode terminal 17 Explosion-proof valve 18 Extraction lead 19 Extraction lead 20 Metal conduction plate 21 Metal conduction plate 22 Element fixing rod

Claims (3)

While the upper and lower ends open at the anode side, and the other becomes a cathode side, each of the openings in the cylindrical metal casing being Rimitsu sealed by the insulating sealing member, the end closer to the sealing body on the anode side A plurality of anode-side lead-out leads are pulled out from the capacitor element from which the plurality of cathode-side lead-out leads are pulled out from an end close to the cathode-side sealing body , and the capacitor element faces the capacitor element inside each sealing body. A metal conductive plate is arranged and fixed on the side, a plurality of anode terminals are arranged on the anode side sealing body, and a plurality of cathode terminals are arranged on the cathode side sealing body, respectively. The terminal of each penetrates the sealing body and the metal conductive plate, the inner end thereof protrudes, and each terminal is connected to the metal conductive plate, and a plurality of anode-side or cathode-side lead-out leads pulled out from the capacitor element. Disperse Electric double layer capacitor, characterized in that it is connected to the inner end of several of the anode terminal or the cathode terminal. 2. The electric double-layer capacitor according to claim 1, wherein a round rod-shaped element fixing rod partially inserted into a center of the capacitor element and holding and fixing the capacitor element is arranged and fixed at the center of at least one of the metal conductive plates . The element fixing rod having one end fixed to one side of the sealing body penetrates the metal conductive plate so as not to contact the metal conductive plate, and the other end is connected to the sealing body on the other side through the center of the capacitor element. The electric double-layer capacitor according to claim 1, wherein

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