JP2010199472A - Electric double-layer capacitor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To achieve miniaturization and reduced cost of an electric double-layer capacitor used for assisting various kinds of power supplies and so on. <P>SOLUTION: The electric double-layer capacitor includes: a flat element 1 out of which a pair of electrodes are led from both end surfaces; a pair of lead wires 6 and 7 joined to electrode lead-out parts 2c and 3c of the element 1; a flat cylinder type metal case 8 which stores the element 1 together with an electrolyte; and sealing rubbers 9 having holes 9a into which the pair of lead wires 6 and 7 are inserted, fitted in openings at both ends of the metal case 8, and compressed by processing the metal case 8 to seal the case 8. The simple configuration makes it possible to achieve the cost reduction by decreasing the number of components and the working man-hours, and also the miniaturization and low resistance. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an electric double layer capacitor used for various electronic devices, electric devices, portable devices and the like.

  The electric double layer capacitor uses electric energy accumulated in the electric double layer formed at the interface between the polarizable electrode and the electrolytic solution. Such an electric double layer capacitor can be reduced in size, and As a capacitor capable of charging a large capacity, it is widely used for microcomputers, memories, timer backups, various power supply assists, and the like.

  FIG. 7 is a cross-sectional view showing the structure of a conventional electric double layer capacitor of this type. In FIG. 7, reference numeral 21 denotes an electric double layer capacitor, and this electric double layer capacitor 21 has a length impregnated with an electrolyte solution. A plurality of electrode plates 23 are laminated so that different poles face each other through the separator 22 between the bellows-like separators 22 in which the separators 22 are alternately folded back in different directions for each predetermined length. . A flexible current collecting member 24 having the same width as that of the electrode plate 23 is connected to the end of each electrode plate 23, and the current collecting member 24 is embedded over the entire length of the electrode plate 23.

  One end of each electrode plate 23 is encased by the separator 22 folded in a bellows shape as described above, and the other end not encased in the separator 22 is exposed on the side surface. The member 24 is pulled out from between the separators 22 at the exposed end. Since the end portions of the electrode plates 23 are alternately exposed on the side surfaces on the opposite side, the current collecting members 24 are collected for each of the same poles, and are bound by a binding member 25 having a C-shaped cross section. The bundling member 25 itself is made of a conductive material.

  Then, the binding portions 26 and 27 of the current collecting member 24 by the binding member 25 are arranged on the outermost layer side in the stacking direction of the electrode plate 23 different for each pole, for example, in the case of FIG. On the side, the binding portion 27 is arranged on the lowermost layer side, and further, the electric double layer capacitor 21 thus configured is configured to be stacked in the stacking direction of the electrode plate 23. It is.

  In the conventional electric double layer capacitor 21 configured in this way, the current collecting member 24 is pulled out by pulling out the flexible current collecting member 24 connected to the end of each electrode plate 23 from between the separators 22. When the current collectors 24 are connected to the electrode plates 23, the separators 22 can be easily manufactured without being damaged, and the electric double layer capacitor can be easily manufactured. 21 is a single cell, and by stacking the single cells, it can be easily connected in series.

As prior art document information related to the invention of this application, for example, Patent Document 1 is known.
Japanese Patent No. 3423852

  However, the conventional electric double layer capacitor 21 can be easily manufactured without damaging the separator 22, and can be easily connected in series by stacking the single cells. In order to make a capacitor device by impregnating an electrolyte solution into such a single cell or a plurality of stacked cells, a case member made of polytetrafluoroethylene (PTFE), which is a non-conductive resin, is used. Thus, there is a problem that the single cell or a plurality of stacked cells must be accommodated and sealed, resulting in an increase in size of the product and a high cost.

  An object of the present invention is to solve such a conventional problem and to provide an electric double layer capacitor that can be reduced in size and cost with a simple configuration.

  In order to solve the above problems, the present invention provides a flat element obtained by taking out a pair of electrodes from opposing end faces, a pair of lead wires respectively joined to the pair of electrodes of the element, and the element as an electrolyte. A flat cylindrical metal case housed together with a hole through which a pair of lead wires joined to the element is inserted, and fitted into openings at both ends of the metal case, respectively, and compressed and sealed by processing the metal case. It is made up of a sealing rubber for stopping.

  As described above, the electric double layer capacitor according to the present invention has a simple configuration with a configuration in which a flat element obtained by taking a pair of electrodes from opposing end faces is housed in a flat cylindrical metal case and sealed. In addition to realizing a reduction in cost by reducing the number of points and man-hours, it is possible to obtain an effect that a reduction in size and a reduction in resistance can be achieved.

(Embodiment 1)
In the following, the first aspect of the present invention will be described using the first embodiment.

  1 (a) to 1 (d) are exploded perspective views showing the configuration of the electric double layer capacitor according to Embodiment 1 of the present invention, and FIG. 2 is a perspective view showing elements used in the electric double layer capacitor. FIG. 3 is a cross-sectional view showing the configuration of the element. In FIGS. 1 to 3, the number of stacked layers is reduced and the thickness in the stacking direction is increased in order to make the configuration of the elements easier to understand. Is.

  1 to 3, reference numeral 1 denotes a flat element. This element 1 is an anode in which a polarizable electrode layer 2b is formed on a current collector 2a made of an aluminum foil except for an electrode non-formed portion provided at one end. The electrode 2 and the cathode electrode 3 having the polarizable electrode layer 3b formed on the current collector 3a made of aluminum foil except for the electrode non-formation portion provided at one end are formed as the electrode non-formation portion of the anode electrode 2 and the cathode The electrode non-formed portions of the electrode 3 are arranged in the opposite directions and overlapped, and the separator 4 is interposed therebetween, and the polarizable electrode layer 2b of the anode electrode 2 and the polarizable electrode layer 3b of the cathode electrode 3 Are wound in a state of being opposed to each other, so that the electrode-unformed portions of the anode electrode 2 and the cathode electrode 3 are exposed on the opposing end surfaces, so that the anode electrode extraction portion 2c and the cathode electrode extraction portion 3c are formed. And finally fixed The over-flop 5 is one that is configured by winding the outermost periphery.

  In addition, the element 1 configured as described above is manufactured by being rolled into a flat shape after being rolled into a cylindrical shape, or wound into a flat shape from the beginning.

  Reference numerals 6 and 7 denote an anode lead wire and a cathode lead wire in which one ends are joined to the anode electrode take-out portion 2c and the cathode electrode take-out portion 3c formed on both end faces of the element 1, respectively. The anode lead wire 6 and the cathode lead wire 7 are formed by joining a copper-based tinned iron wire (generally called a CP wire, hereinafter referred to as a CP wire) to one end of an aluminum round wire. Yes, a part of the aluminum round wire different from the joint with the CP wire is processed into a flat part to provide joints 6a and 7a. The joints 6a and 7a are formed on both end faces of the element 1. The anode electrode take-out portion 2c and the cathode electrode take-out portion 3c are joined by laser welding (welding marks 6b and 7b), respectively. The other end of the CP lead of the anode lead wire 6 and the cathode lead wire 7 is finally processed into flat connection portions 6c and 7c by press working.

  8 is a flat metal case made of aluminum containing the element 1 together with an electrolyte (not shown), and 9 is an anode lead wire 6 joined to the anode electrode extraction part 2c and the cathode electrode extraction part 3c of the element 1, respectively. These are sealing rubbers provided with holes 9a through which the cathode lead wires 7 are inserted and fitted into openings at both ends of the metal case 8, respectively. The sealing rubber 9 has a plurality of recesses from the outer surface of the metal case 8 to the inside at the contact portion with the sealing rubber 9 of the curling process (curling process part 8a) in the vicinity of the opening of the metal case 8. The metal case 8 is sealed by being compressed by performing a drawing process (drawing part 8 b) to form a metal.

  Reference numeral 8c denotes a recess provided so as to extend from a part of the flat portion of the metal case 8 to the inside, and the recess 1c compresses the element 1 accommodated in the metal case 8 in the thickness direction. Although not shown, it is also provided on the bottom side (opposite side) in FIG.

  The concave portion 8c provided in the metal case 8 has an area of 15% or more of the area of the element 1 accommodated in the metal case 8 excluding the anode electrode extraction portion 2c and the cathode electrode extraction portion 3c. And the compression ratio of the thickness dimension of the element 1 is 0.5 to 20%. By doing so, the element 1 is prevented from being swollen and an unnecessary resistance is increased. In addition to preventing this, the strength of the metal case 8 can be improved.

  Further, by providing a resin layer (not shown) made of polyethylene terephthalate (PET) or 6 nylon on the inner surface of the metal case 8, the resin layer prevents the anode electrode 2 and the cathode electrode 3 from being short-circuited, resulting in higher reliability. This is preferable in order to be able to exhibit properties.

  Further, the outer diameter of the sealing rubber 9 is larger than the inner diameter of the metal case 8 so as to be press-fitted into the metal case 8 and the anode lead provided on the sealing rubber 9. The hole 9a through which the wire 6 and the cathode lead wire 7 are inserted is formed smaller than the outer diameter of the anode lead wire 6 and the cathode lead wire 7 so that the anode lead wire 6 and the cathode lead wire 7 are press-fitted. Therefore, the sealing performance is enhanced by these press-fitting.

  The polarizable electrode layers 2b and 3b respectively formed on the anode electrode 2 and the cathode electrode 3 are formed by kneading activated carbon powder, carbon black and a binder, and the activated carbon powder includes a wood powder type, A material obtained by activating coconut shell-based, phenolic resin-based, petroleum coke-based, coal coke-based, or pitch-based materials is used. As the binder, a mixture of polytetrafluoroethylene and carboxymethylcellulose water-soluble binder is used.

  Further, in the present embodiment, isobutylene isoprene rubber (IIR) is used as the sealing rubber 9, and this IIR does not permeate the electrolytic solution, but allows the gas generated inside the capacitor to escape to the outside. Although it is preferable because it is possible, the present invention is not limited to this.

In addition, as the above-mentioned electrolytic solution, it is possible to use propylene carbonate, γ-butyrolactone, ethylene carbonate, sulfolane, acetonitrile, dimethyl carbonate, diethyl carbonate, or methyl ethyl carbonate as a solvent, or a mixture of two or more. it can. As the electrolyte cation, quaternary ammonium, quaternary phosphonium, imidazolium salt can be used, and as the electrolyte anion, BF ₄ ⁻ , PF ₆ ⁻ , ClO ₄ ⁻ , CF ₃ SO ₃ ^— or N (CF ₃ SO _{3 2) 2} ^- in which can be used.

  Next, the manufacturing method of the electric double layer capacitor according to the present embodiment configured as described above will be described. First, as shown in FIGS. 2 and 3, a current collector 2a made of aluminum foil is provided at one end. The polarizable electrode layer 3b was formed by removing the anode electrode 2 formed with the polarizable electrode layer 2b except for the electrode-unformed portion and the non-electrode-formed portion provided at one end on the current collector 3a made of aluminum foil. The cathode electrode 3 is paired, and the anode electrode 2 and the electrode non-formed portion provided on the cathode electrode 3 are arranged in the opposite directions to overlap each other, and a separator 4 is interposed therebetween to separate the anode electrode 2. When the polar electrode layer 2b and the polarizable electrode layer 3b of the cathode electrode 3 are wound in a state of being opposed to each other with the separator 4 interposed therebetween, the electrode unformed portions of the anode electrode 2 and the cathode electrode 3 are exposed on the opposing end surfaces. Take out the anode To produce a device 1 pole extraction portion 2c and the cathode electrode extraction portion 3c is formed, after winding the fixing tape 5 on the outer periphery Finally, processing the device 1 into a flat shape by pressing.

  Next, as shown in FIG. 1 (a), an anode lead wire 6 and a cathode lead wire 7 in which a CP wire is joined to one end of an aluminum round wire are prepared, and a part of the aluminum round wire is processed into a flat shape. Then, the joint portions 6a and 7a are provided, and the joint portions 6a and 7a are laser-welded (welding marks 6b and 7b) to the anode electrode extraction portion 2c and the cathode electrode extraction portion 3c formed on both end faces of the element 1, respectively. As a result, the anode lead wire 6 and the cathode lead wire 7 are joined to the element 1.

  Next, the sealing rubber 9 is prepared, and the anode lead wire 6 joined to the anode electrode take-out portion 2c of the element 1 is inserted into the hole 9a provided in the sealing rubber 9, and shown in FIG. Thus, the sealing rubber 9 is fitted so as to be in close contact with the element 1.

  Next, as shown in FIG. 1 (c), a metal case 8 formed in a flat cylindrical shape is prepared, and the element 1 in which the sealing rubber 9 is fitted on the anode electrode extraction portion 2 c side is placed in the metal case 8. With the sealing rubber 9 inserted and disposed in the vicinity of one opening of the metal case 8, the vicinity of the opening of the metal case 8 is curled (curling part 8 a), and the sealing rubber 9 of the metal case 8 is used. A plurality of concave portions (drawing portions 8b) are formed by drawing from the outer surface of the metal case 8 toward the inside at the abutting portion, and thereby the sealing rubber 9 is compressed.

  Next, by injecting an electrolyte solution (not shown) from the cathode electrode extraction portion 3c side of the element 1 inserted into the case 8, the element 1 is impregnated with the electrolyte solution, and then the cathode electrode extraction portion 3c side of the element 1 The sealing rubber 9 is fitted in, the sealing rubber 9 is fitted from the anode electrode take-out portion 2c side of the element 1, and the metal case 8 is repeated by repeating the same work as the curling process and the drawing process. Seal.

  Next, as shown in FIG. 1 (d), a concave portion 8 c is formed by pressing a part of the flat portion of the metal case 8 toward the inside, thereby being accommodated inside the metal case 8. The obtained element 1 is compressed in the thickness direction. Although not shown in the figure, a recess 8c is similarly formed in the metal case 8 on the bottom side (opposite side) in FIG.

  Finally, flat-shaped connecting portions 6c and 7c are formed by pressing the anode lead wire 6 and the CP wire of the cathode lead wire 7 exposed from both ends of the metal case 8, thereby forming the present embodiment. Thus, the electric double layer capacitor 10 is manufactured.

  The manufacturing method described above shows one example of the embodiment of the present invention. The present invention is not limited to this, and the order of each step is partially changed. Needless to say, it may be determined appropriately while considering work efficiency and production efficiency, such as adding new processes.

  The electric double layer capacitor 10 according to this embodiment configured as described above has a configuration in which a flat element 1 in which a pair of electrodes are taken out from opposing end faces is accommodated in a flat cylindrical metal case 8 and sealed. As a result, it is possible to reduce the number of parts and the number of work steps with a simple configuration, thereby realizing a reduction in cost and at the same time achieving a special effect of being able to reduce the size and the resistance.

  In addition, the flat element 1 impregnated with the electrolytic solution is housed in the flat cylindrical metal case 8 and sealed with the sealing rubber 9 so that high sealing performance can be exhibited. It has a special effect.

  In the present embodiment, the flat cylindrical metal case 8 is used as the metal case in which the flat element 1 impregnated with the electrolytic solution is accommodated. However, the present invention is limited to this. Instead of a flat cylindrical metal case 8, not shown, but comprising a concave metal case with an open upper surface and a flat metal lid coupled to the upper surface of the metal case It can be used, and with such a configuration, the operation for inserting the element into the metal case can be facilitated.

(Embodiment 2)
The second aspect of the present invention will be described below with reference to the second embodiment.

  In the present embodiment, the configuration of elements used in the electric double layer capacitor described in Embodiment 1 with reference to FIGS. 1 to 3 is partially different, and other configurations are implemented. Therefore, the same parts are denoted by the same reference numerals and detailed description thereof will be omitted, and only different parts will be described in detail below with reference to the drawings.

  4 is a perspective view showing the configuration of an element used in the electric double layer capacitor according to the second embodiment of the present invention, and FIGS. 5A to 5D are exploded perspective views showing the configuration of the electric double layer capacitor. In FIGS. 4 and 5, reference numeral 11 denotes a flat element, and this element 11 is provided at one end on a current collector 2a made of aluminum foil, like the element 1 described in the first embodiment. The polarizable electrode layer 3b is formed except for the anode electrode 2 in which the polarizable electrode layer 2b is formed except for the provided electrode-unformed portion, and the non-electrode-formed portion provided at one end on the current collector 3a made of aluminum foil. The formed cathode electrode 3 is overlapped with the electrode non-formed part of the anode electrode 2 and the electrode non-formed part of the cathode electrode 3 arranged in opposite directions, and the separator 4 is interposed between them. Separation of polarizable electrode layer 2b and cathode electrode 3 When the conductive electrode layer 3b is wound in a state of being opposed to each other with the separator 4 interposed therebetween, the electrode unformed portions of the anode electrode 2 and the cathode electrode 3 are exposed on the opposing end surfaces, respectively, and the anode electrode extraction portion 2c and the cathode electrode are exposed. It is the same that the take-out portion 3c is formed and the fixing tape 5 is wound around the outermost periphery.

  The element 11 configured as described above further compresses the anode electrode extraction portion 2c and the cathode electrode extraction portion 3c, which are formed of the electrode unformed portions of the anode electrode 2 and the cathode electrode 3 exposed on the opposing end surfaces, respectively. By welding (welding marks 2d, 3d), the plurality of anode electrodes 2 and the plurality of cathode electrodes 3 are integrally joined to each other.

  Further, a method for manufacturing the electric double layer capacitor according to the present embodiment using the element 11 configured as described above will be described. First, as shown in FIG. The anode 11 is connected to the element 11 by laser welding the welding portion 6a of the anode lead wire 6 and the joining portion 7a of the cathode lead wire 7 to the anode electrode extraction portion 2c and the cathode electrode extraction portion 3c, respectively. The lead wire 6 and the cathode lead wire 7 are joined.

  Next, as shown in FIG. 5B, the anode lead wire 6 joined to the anode electrode take-out portion 2c of the element 11 is inserted into the hole 9a provided in the sealing rubber 9, and the sealing rubber 9 is attached to the element. 11 so that it is in close contact with 11.

  Next, as shown in FIG. 5C, the element 11 having the sealing rubber 9 fitted on the anode electrode take-out portion 2c side is inserted into a flat cylindrical metal case 8, and the sealing rubber 9 is inserted into the metal case. In the state of being disposed in the vicinity of one opening of the metal case 8, the vicinity of the opening of the metal case 8 is curled (curling portion 8 a), and the metal case 8 is in contact with the sealing rubber 9 at the contact portion of the metal case 8. A plurality of concave portions (drawing portions 8b) are formed by drawing from the outer surface toward the inside, and thereby the sealing rubber 9 is compressed.

  Next, by injecting an electrolyte solution (not shown) from the cathode electrode extraction portion 3c side of the element 11 inserted into the case 8, the element 11 is impregnated with the electrolyte solution, and then the cathode electrode extraction portion 3c side of the element 11 The sealing rubber 9 is fitted in, the sealing rubber 9 is fitted from the anode electrode take-out portion 2c side of the element 11, and the metal case 8 is repeated by repeating the same work as the curling process and the drawing process. Seal.

  Next, as shown in FIG. 5 (d), a concave portion 8 c is formed by pressing a part of the flat portion of the metal case 8 toward the inside, thereby being accommodated inside the metal case 8. The device 11 is compressed in the thickness direction. Although not shown in the figure, a recess 8c is similarly formed in the metal case 8 on the bottom side (opposite side) in FIG.

  Finally, flat-shaped connecting portions 6c and 7c are formed by pressing the anode lead wire 6 and the CP wire of the cathode lead wire 7 exposed from both ends of the metal case 8, thereby forming the present embodiment. Thus, the electric double layer capacitor 12 is manufactured.

  The electric double layer capacitor 12 according to the present embodiment configured as described above has an anode electrode lead-out portion exposed on the opposing end face of the element 11 in addition to the effects obtained by the electric double layer capacitor 10 according to the first embodiment. 2c and cathode electrode take-out portion 3c are compressed and welded (welding marks 2d and 3d), respectively, so that a plurality of anode electrodes 2 and a plurality of cathode electrodes 3 are integrally joined to each other, and anode electrode take-out portion 2c and This brings about a special effect that each resistance value in the cathode electrode lead-out portion 3c can be reduced.

(Embodiment 3)
Hereinafter, the invention described in the ninth aspect of the present invention will be described with reference to the third embodiment.

  In the present embodiment, the electric double layer capacitor described with reference to FIGS. 1 to 5 in the first and second embodiments is used as one cell, and a plurality of these cells are connected and accommodated in a case. Since the other points are the same as in the first and second embodiments, the same reference numerals are given to the same parts, and detailed descriptions thereof are omitted, and only the different parts are described. This will be described in detail below with reference to the drawings.

  6 (a) to 6 (c) are exploded perspective views showing the configuration of the electric double layer capacitor according to Embodiment 3 of the present invention, an exploded perspective view seen from the direction of arrow A in FIG. 6 is a perspective view, and in FIG. 6, reference numeral 13 denotes a resin case having an open top surface, and reference numeral 14 denotes a lid that covers the upper surface of the case 13. The electric double layer described in the first embodiment is contained in the case 13. Two electric double layer capacitors 10a and 10b configured similarly to the capacitor 10 (or the electric double layer capacitor 12 described in the second embodiment) are accommodated so as to be adjacent to each other.

  Reference numerals 15a and 16b denote an external anode terminal and an external cathode terminal provided in the case 13, and the anode lead wire 6 led out from the one electric double layer capacitor 10a is connected to the external anode terminal 15a and the external cathode terminal 16b. The cathode lead wires 7 drawn from the other electric double layer capacitor 10b are connected to each other (state shown in FIG. 6A).

  Further, the cathode lead wire 7 drawn out from the one electric double layer capacitor 10a and the anode lead wire 6 drawn out from the other electric double layer capacitor 10b are provided in the case 13, as shown in FIG. The external cathode terminal 16a and the external anode terminal 15b are connected to each other, and the external anode terminal 15b and the external cathode terminal 16a are connected to the outside of the case 13 by an external intermediate terminal 17, thereby two electric terminals. The double layer capacitors 10a and 10b are connected in series.

  Then, the cover 14 is put on the upper surface opening portion of the case 13 containing the two electric double layer capacitors 10a and 10b in this way, and the case 13 and the cover 14 are coupled by means such as laser welding or bonding, thereby As shown in FIG. 6C, the electric double layer capacitor according to the present embodiment is configured.

  The electric double layer capacitor according to the present embodiment configured as described above is formed by connecting a plurality of electric double layer capacitors in addition to the effects obtained by the electric double layer capacitors according to the first and second embodiments. By integrating, it is possible to achieve a special effect that a small size and large capacity can be realized.

  In the present embodiment, the description has been given using the example in which two electric double layer capacitors are connected in series and accommodated in the case. However, the present invention is not limited to this, and two or more electric double layer capacitors are included. It goes without saying that electric double layer capacitors can be accommodated in a case connected in series or in parallel.

  The electric double layer capacitor according to the present invention has an effect of reducing the number of parts and working man-hours with a simple configuration, realizing a reduction in cost, and achieving a reduction in size and a resistance. It is useful as a field for assisting.

(A)-(d) The exploded perspective view which showed the structure of the electrical double layer capacitor by Embodiment 1 of this invention The perspective view which showed the element used for the same electric double layer capacitor Sectional view showing the configuration of the element The perspective view which showed the structure of the element used for the electric double layer capacitor by Embodiment 2 of this invention (A)-(d) The exploded perspective view which showed the structure of the same electric double layer capacitor (A) An exploded perspective view showing a configuration of an electric double layer capacitor according to Embodiment 3 of the present invention, (b) an exploded perspective view seen from the direction of arrow A in (a), (c) a perspective view after assembly. Figure Sectional view showing the configuration of a conventional electric double layer capacitor

DESCRIPTION OF SYMBOLS 1, 11 Element 2 Anode electrode 2a, 3a Current collector 2b, 3b Polarized electrode layer 2c Anode electrode extraction part 2d, 3d, 6b, 7b Welding trace 3 Cathode electrode 3c Cathode electrode extraction part 4 Separator 5 Fixing tape 6 Anode lead Wire 6a, 7a Junction portion 6c, 7c Connection portion 7 Cathode lead wire 8 Metal case 8a Curling processing portion 8b Drawing processing portion 8c Recess 9 Sealing rubber 9a Hole 10, 10a, 10b, 12 Electric double layer capacitor 13 Case 14 Lid 15a, 15b External anode terminal 16a, 16b External cathode terminal 17 External intermediate terminal

Claims (9)

A flat element in which a pair of electrodes are respectively taken out from opposing end faces; a pair of lead wires respectively joined to the pair of electrodes of the element; a flat cylindrical metal case containing the element together with an electrolyte; An electric double layer capacitor comprising a sealing rubber that is provided with holes through which a pair of lead wires joined to the element is inserted and is fitted into openings at both ends of the metal case, and is compressed and sealed by processing the metal case . A flat element obtained by taking out a pair of electrodes from the opposing end faces has an anode electrode and a cathode electrode in which a polarizable electrode layer is formed on a current collector made of metal foil except for an electrode non-formed portion provided at one end. A plurality of anode electrodes and a plurality of cathode electrodes are formed by winding a pair of anode electrode and cathode electrode non-formed portions in opposite directions and winding them with a separator interposed therebetween. 2. The electric double layer capacitor according to claim 1, wherein each electrode non-formed portion of the electrode is exposed to an opposing end surface to form an anode electrode take-out portion and a cathode electrode take-out portion, respectively. An anode electrode take-out portion in which a plurality of anode electrodes are integrated by compressing and welding the respective electrode-unformed portions of the plurality of anode electrodes and the plurality of cathode electrodes exposed on the opposing end faces of the flat element The electric double layer capacitor according to claim 2, wherein a cathode electrode lead-out portion in which a plurality of cathode electrodes are integrated is formed. 2. The electric double layer capacitor according to claim 1, wherein a concave portion directed from the outer surface to the inside is provided in the metal case, and the element accommodated in the case is compressed by the concave portion. The electric double layer capacitor according to claim 1, wherein a concave portion directed from the outer surface to the inside is provided at a contact portion of the metal case with the sealing rubber, and the sealing rubber fitted inside is compressed by the concave portion. The electric double layer capacitor according to claim 1, wherein the sealing rubber that is fitted into the opening of the metal case for sealing is formed of isobutylene isoprene rubber (IIR). The electric double layer capacitor according to claim 1, wherein a resin layer made of polyethylene terephthalate (PET) or 6 nylon is provided on the inner surface of a metal case containing the element together with an electrolytic solution. 2. The electric double layer capacitor according to claim 1, wherein, instead of the flat cylindrical metal case, a concave metal case having an open upper surface and a flat metal lid coupled to the upper surface of the metal case are used. The electric double layer capacitor which made the electric double layer capacitor as described in any one of Claims 1-8 one cell, and connected this cell in multiple numbers and accommodated in the case.

Images