JP2005079485A

JP2005079485A - Electric double layer capacitor

Info

Publication number: JP2005079485A
Application number: JP2003310864A
Authority: JP
Inventors: Masashi Mizuguchi; 政志水口
Original assignee: NEC Tokin Corp; NEC Tokin Ceramics Corp
Current assignee: Tokin Corp; NEC Tokin Hyogo Ltd
Priority date: 2003-09-03
Filing date: 2003-09-03
Publication date: 2005-03-24

Abstract

<P>PROBLEM TO BE SOLVED: To miniaturize an electric double layer capacitor enclosed in a square shaped case wherein current collectors of a positive electrode and a negative electrode having polarizable electrode layers on the surfaces thereof are laminated with a separator interposed between them. <P>SOLUTION: The capacitor 7 is formed by making a positive electrode current extraction portion 3a, a negative electrode current extraction portion 3b integrated with a positive electrode current collector 1a, a negative electrode current collector 1b respectively, and disposing them in a opposed relation in the direction perpendicular to the lamination direction of the current collectors, and laminating them integratedly, and then bending them along the laminated body of the current collectors with an insulator 5 being interposed between them. In such a structure, the current extraction portions have no projecting portion so that unnecessary space that does not contribute to an electrostatic capacity becomes very small in the case enclosing the capacitor element, thus the square-shaped electric double layer capacitor can be miniaturized. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

本発明は、電気二重層キャパシタに関わり、特に、ケース内の容積を有効に利用することで、小型化を図った電気二重層キャパシタに関わるものである。 The present invention relates to an electric double layer capacitor, and more particularly to an electric double layer capacitor that is miniaturized by effectively utilizing the volume in the case.

電気二重層キャパシタは、電荷を有する固体と、それに接触する電解液の界面に形成される、厚さ数ｎｍ程度の電気二重層を、誘電体として利用したものである。電気二重層の容量は、１ｃｍ²あたり数十μＦであるが、表面積が数千ｍ²にも及ぶ活性炭を電極として用いることにより、数百〜数千Ｆの極めて大きな容量を得ることが可能である。 An electric double layer capacitor uses an electric double layer having a thickness of several nanometers formed as a dielectric at the interface between a solid having electric charge and an electrolyte solution in contact therewith. The capacity of the electric double layer is several tens of μF per 1 cm ² , but it is possible to obtain an extremely large capacity of several hundred to several thousand F by using activated carbon having a surface area of several thousand m ² as an electrode. is there.

そして、電気二重層キャパシタは、下記のような特徴を有し、実用に供されるとともに、さらなる性能向上のための検討がなされている。
（１）充放電サイクルに伴う容量の劣化が少ない。
（２）一般的な電池に比較して、起動後に瞬時に大きな出力を取り出せる。 The electric double layer capacitor has the following characteristics and is put into practical use and has been studied for further performance improvement.
(1) There is little deterioration of the capacity accompanying a charge / discharge cycle.
(2) Compared with a general battery, a large output can be taken out instantly after startup.

現用の電気二重層キャパシタで、小型のものは、表面に活性炭を主とする分極性電極層を形成した一対の集電体の間に、ポリプロピレン不織布などからなるセパレータを挟んで素子とし、この素子に電解液を含浸させ、金属容器に収容し、キャップとガスケットにより金属容器に密封したコイン型の構造をとっている。 A small-sized electric double layer capacitor in use is an element in which a separator made of polypropylene nonwoven fabric is sandwiched between a pair of current collectors having a polarizable electrode layer mainly composed of activated carbon on the surface. It is impregnated with an electrolytic solution, accommodated in a metal container, and has a coin-type structure sealed in a metal container with a cap and a gasket.

また、比較的大容量のものとして、シート状の分極性電極、集電体、セパレータを積層して渦巻状に巻き回してキャパシタ素子とし、この素子に電解液を含浸させ、金属容器に収容し、容器の開口部をキャップで密閉して構成した、巻回型の電気二重層キャパシタが製造されている。 In addition, as a relatively large capacity, a sheet-like polarizable electrode, a current collector, and a separator are stacked and wound in a spiral shape to form a capacitor element, which is impregnated with an electrolytic solution and accommodated in a metal container. A wound-type electric double layer capacitor is manufactured in which the opening of a container is sealed with a cap.

この他に、小型化、薄型化を目的に、シート状の分極性電極、集電体、セパレータを複数枚積層して、扁平な直方体のケースに封入した、角型の電気二重層キャパシタも製造されている。そして、これらの電気二重層キャパシタは、主にＩＣメモリのバックアップやアクチュエータのバックアップに使用されている。 In addition, for the purpose of miniaturization and thinning, a rectangular electric double layer capacitor is also manufactured, in which a plurality of sheet-shaped polarizable electrodes, current collectors, and separators are stacked and enclosed in a flat rectangular parallelepiped case. Has been. These electric double layer capacitors are mainly used for IC memory backup and actuator backup.

図７は、前記３種類の中の、角型の電気二重層キャパシタを示した図で、図７（ａ）は、内部を透視した斜視図、図７（ｂ）は、断面図である。図７において、２２ａは正極集電体、２２ｂは負極集電体、２３ａは正極電流取出部、２３ｂは負極電流取出部、２４ａは正極外部接続端子、２４ｂは負極外部接続端子、２５はキャパシタ素子、２６は外装ケースである。 FIG. 7 is a diagram showing a square electric double layer capacitor among the above three types. FIG. 7A is a perspective view seeing through the inside, and FIG. 7B is a cross-sectional view. In FIG. 7, 22a is a positive electrode current collector, 22b is a negative electrode current collector, 23a is a positive electrode current extraction part, 23b is a negative electrode current extraction part, 24a is a positive electrode external connection terminal, 24b is a negative electrode external connection terminal, and 25 is a capacitor element. , 26 is an exterior case.

図７に示した角型の電気二重層キャパシタは、導電性材料からなる正極集電体２２ａ、負極集電体２２ｂの表面に、それぞれ分極性電極層（図示せず）を形成し、正極電流取出部２３ａ、負極電流取出部２３ｂを、それぞれ取り付けた後、セパレータ（図示せず）を介して、交互に所要枚数積層し、複数の電流取出部を、極ごとに一体化して、それぞれ正極外部接続端子２４ａ、負極外部接続端子２４ｂを取り付けている。 The square electric double layer capacitor shown in FIG. 7 has a polarizable electrode layer (not shown) formed on the surfaces of the positive electrode current collector 22a and the negative electrode current collector 22b made of a conductive material, respectively. After attaching the extraction part 23a and the negative electrode current extraction part 23b, respectively, a required number of layers are alternately stacked via a separator (not shown), and a plurality of current extraction parts are integrated for each pole, respectively. A connection terminal 24a and a negative external connection terminal 24b are attached.

このような構造の電気二重層キャパシタでは、電流取出部を集電体から突出した形で取り付ける必要がある。図７に示した場合では、図における上の方に、電流取出部を突出させて設けてあるため、外装ケース２６の内部に、破線で示した静電容量に寄与しない不要スペース２７が生じてしまう。また、電気抵抗を低く抑えるには、電流取出部の面積を大きくするのが効果的であるが、このような構造のままで面積を大きくすると、正負の電流取出部の接触によるショートを招く虞がある。 In the electric double layer capacitor having such a structure, it is necessary to attach the current extraction portion so as to protrude from the current collector. In the case shown in FIG. 7, since the current extraction portion is provided so as to protrude upward in the drawing, an unnecessary space 27 that does not contribute to the electrostatic capacitance indicated by the broken line is generated inside the outer case 26. End up. In order to keep the electrical resistance low, it is effective to increase the area of the current extraction part. However, if the area is increased with such a structure, a short circuit due to contact between the positive and negative current extraction parts may be caused. There is.

このような角型の電気二重層キャパシタにおける、電流取出部の構造については、下記の特許文献１、特許文献２に開示されている。しかしながら、前記不要スペース形成への対処方法については、何ら言及されていないものである。 The structure of the current extraction part in such a square electric double layer capacitor is disclosed in Patent Document 1 and Patent Document 2 below. However, there is no mention of a method for dealing with the formation of the unnecessary space.

特開平１０−７４６７２号公報Japanese Patent Laid-Open No. 10-74672 特開２０００−２００７３８号公報Japanese Patent Application Laid-Open No. 2000-200738

従って、本発明の課題は、表面に分極性電極を形成した正負の集電体を、セパレータを介して積層したキャパシタ素子を、角型のケースに封入した電気二重層キャパシタであって、所要の導電性を確保し得る電流取出部を有し、かつ、ケース内の不要なスペースが極めて少ない電気二重層キャパシタを提供することにある。 Therefore, an object of the present invention is an electric double layer capacitor in which a capacitor element in which a positive and negative current collector having a polarizable electrode formed on a surface thereof is laminated via a separator is enclosed in a square case, An object of the present invention is to provide an electric double layer capacitor that has a current extraction portion that can ensure conductivity and that has very little unnecessary space in a case.

本発明は、前記の問題解決のため、電流取出部と、外部接続端子への電流取出部の取り付け構造を再検討した結果なされたものである。 The present invention has been made as a result of reexamination of the mounting structure of the current extraction portion and the current extraction portion to the external connection terminal in order to solve the above problem.

即ち、本発明は、表面に正極分極性電極層が形成され、正極電流取出部を有する少なくとも１枚の正極集電体と、表面に負極分極性電極層が形成され、負極電流取出部を有する少なくとも１枚の負極集電体とを、セパレータを介して積層したキャパシタ素子と、前記キャパシタ素子に含浸された電解液と、前記キャパシタ素子封入用のケースを有する電気二重層キャパシタにおいて、前記正極電流取出部と負極電流取出部とは、それぞれ前記キャパシタ素子の積層方向に垂直な方向の、対向する側に配置されて積層一体化され、絶縁体を介在させた状態で、前記キャパシタ素子の表面に沿って折り曲げられてなることを特徴とする電気二重層キャパシタである。 That is, in the present invention, at least one positive electrode current collector having a positive electrode polarizable electrode layer formed on the surface and having a positive electrode current extraction part, and a negative electrode polarizable electrode layer formed on the surface and having a negative electrode current extraction part. In the electric double layer capacitor having a capacitor element in which at least one negative electrode current collector is laminated via a separator, an electrolytic solution impregnated in the capacitor element, and a case for enclosing the capacitor element, the positive current The extraction part and the negative electrode current extraction part are arranged on opposite sides in the direction perpendicular to the stacking direction of the capacitor element, and are laminated and integrated on the surface of the capacitor element with an insulator interposed therebetween. It is an electric double layer capacitor characterized by being bent along.

また、本発明は、前記正極電流取出部と前記負極電流取出部が、それぞれ外部接続端子が取り付けられてなることを特徴とする、前記の電気二重層キャパシタである。 The present invention is the above electric double layer capacitor, wherein the positive current extraction part and the negative current extraction part are each provided with an external connection terminal.

本発明の電気二重層キャパシタにおいては、集電体表面の一部に、分極性電極層を形成しないで、その部分を電流取出部とした構成を用いることができるので、別途に電流取出部を集電体に接合することによる、接合部分に起因する抵抗増加がなく、ショートの可能性が極めて少ない状態で、電流取出部自体の面積を大きくすることも容易である。 In the electric double layer capacitor of the present invention, a configuration in which the polarizable electrode layer is not formed on a part of the current collector surface and that part is used as the current extraction part can be used. By joining to the current collector, there is no increase in resistance due to the joined portion, and it is easy to increase the area of the current extraction portion itself in a state where the possibility of a short circuit is extremely low.

また、同極の電流取出部は、積層して一体化し、キャパシタ素子に沿った状態になるように折り曲げた後に、外部接続端子を取り付けるので、図７に示したような不要スペースが生じない。このため、本発明は、電気二重層キャパシタの小型化や薄型化に寄与するところが大きいものである。 In addition, the current extraction parts of the same polarity are laminated and integrated, and the external connection terminals are attached after being bent so as to be in a state along the capacitor element, so that unnecessary space as shown in FIG. 7 does not occur. Therefore, the present invention greatly contributes to reducing the size and thickness of the electric double layer capacitor.

図１は、本発明を実施するための最良の形態に係る、電気二重層キャパシタのキャパシタ素子を示す図で、図１（ａ）は、斜視図、図１（ｂ）は、断面を模式的に示した図である。図１において、１ａは正極集電体、１ｂは負極集電体、３ａは正極電流取出部、３ｂは負極電流取出部、４ａは正極外部接続端子、４ｂは負極外部接続端子、５は絶縁体、７はキャパシタ素子である。 1A and 1B are diagrams showing a capacitor element of an electric double layer capacitor according to the best mode for carrying out the present invention. FIG. 1A is a perspective view, and FIG. It is the figure shown in. In FIG. 1, 1a is a positive electrode current collector, 1b is a negative electrode current collector, 3a is a positive electrode current extraction part, 3b is a negative electrode current extraction part, 4a is a positive electrode external connection terminal, 4b is a negative electrode external connection terminal, and 5 is an insulator. , 7 are capacitor elements.

また、図２は、電流取出部を有する正負の集電体の積層状態を示す図である。図２において、２ａは正極分極性電極層を形成する部分、２ｂは負極分極性電極層を形成する部分、６は位置決め穴である。 Moreover, FIG. 2 is a figure which shows the lamination | stacking state of the positive / negative collector which has an electric current extraction part. In FIG. 2, 2a is a portion for forming a positive polarizable electrode layer, 2b is a portion for forming a negative polarizable electrode layer, and 6 is a positioning hole.

本発明においては、図２に示したような形状の導電性のシートからなる集電体を準備し、図２における破線で囲んだ部分に分極性電極層を形成し、セパレータ（図示せず）を介して積層する。その際、正負の電流取出部は、図２に示したように、対向する側に配置する。 In the present invention, a current collector made of a conductive sheet having a shape as shown in FIG. 2 is prepared, a polarizable electrode layer is formed in a portion surrounded by a broken line in FIG. 2, and a separator (not shown) Laminate through. At that time, the positive and negative current extraction portions are arranged on opposite sides as shown in FIG.

次に、正負それぞれの電流取出部を密着させて積層一体化し、図における前方に折り曲げ、絶縁体５を介在させた状態で、集電体を積層した部分に密着させ、キャパシタ素子７を得る。その後、正極外部接続端子４ａと、負極外部接続端子４ｂを取り付ける。 Next, positive and negative current extraction portions are brought into close contact to be laminated and integrated, bent forward in the figure, and brought into close contact with the portion where the current collector is laminated, thereby obtaining a capacitor element 7. Thereafter, the positive external connection terminal 4a and the negative external connection terminal 4b are attached.

図３は、外部接続端子を取り付けたキャパシタ素子７を、角型の外装ケース８に封入した状態を、内部を透視して示した斜視図である。図３に示したように、本発明によるキャパシタ素子７は、図における上側に、電流取出部が突出した部分がないので、外装ケース８の内部に、図７に示したような不要スペースを設ける必要がない。 FIG. 3 is a perspective view showing a state in which the capacitor element 7 to which the external connection terminal is attached is enclosed in a rectangular outer case 8 as seen through the inside. As shown in FIG. 3, the capacitor element 7 according to the present invention has no portion where the current extraction portion protrudes on the upper side in the drawing, and therefore an unnecessary space as shown in FIG. 7 is provided inside the outer case 8. There is no need.

次に、具体的な実施例を挙げ、本発明についてさらに詳しく説明する。 Next, the present invention will be described in more detail with specific examples.

まず、第１の実施例について説明する。この場合、集電体の形状は、図２と同様にしたので、図１、図２、図３を用いて説明する。集電体として、厚さが１８μｍのアルミニウム箔を用いた。ここでは、分極性電極層を形成する部分を、縦が８０ｍｍ、横が５０ｍｍの大きさとし、電流取出部を、縦が３６ｍｍ、横が１６ｍｍの大きさとした。 First, the first embodiment will be described. In this case, since the shape of the current collector is the same as that in FIG. 2, the description will be made with reference to FIGS. As the current collector, an aluminum foil having a thickness of 18 μm was used. Here, the portion where the polarizable electrode layer is formed is 80 mm long and 50 mm wide, and the current extraction portion is 36 mm long and 16 mm wide.

次に、比表面積が３０００ｍ²／ｇの活性炭粉末と、カーボンブラックと、フェノール樹脂とを、重量比で７０／５／２５となるように秤量し、活性炭粉末重量の２倍の２−メトシキメタノールを添加して混合し、分極性電極層形成用の混和物を得た。この混和物を正極集電体１ａ、及び負極集電体１ｂの表面にドクターブレードを用いて、乾燥後の厚さが５０μｍとなるように塗布した。 Next, the activated carbon powder having a specific surface area of 3000 m ² / g, carbon black, and phenol resin are weighed so that the weight ratio is 70/5/25, and 2-methoxy having twice the weight of the activated carbon powder. Methanol was added and mixed to obtain an admixture for forming a polarizable electrode layer. This mixture was applied to the surfaces of the positive electrode current collector 1a and the negative electrode current collector 1b using a doctor blade so that the thickness after drying was 50 μm.

このようにして、正極集電体１ａ、負極集電体１ｂを、それぞれ２５枚調製し、乾燥させた後、厚さが１５μｍの多孔質ポリプロピレンフィルムをセパレータとして、正負交互に積層した。次に、正極電流取出部３ａ、負極電流取出部３ｂを、それぞれ密着させて積層一体化し、図１における前方に折り曲げ、厚さが２０μｍのポリプロピレンのシートを絶縁体として介在させた状態で、集電体の積層体に沿わせるように密着させた。その後、正極外部接続端子４ａ、負極外部接続端子４ｂを取り付け、外装ケース８に封入した。 In this manner, 25 positive electrode current collectors 1a and 25 negative electrode current collectors 1b were prepared and dried, and then positive and negative layers were alternately laminated using a porous polypropylene film having a thickness of 15 μm as a separator. Next, the positive electrode current extraction part 3a and the negative electrode current extraction part 3b are brought into close contact with each other and laminated and integrated, bent forward and in FIG. 1, with a polypropylene sheet having a thickness of 20 μm interposed as an insulator. It was stuck so as to be along the laminate of the electric bodies. Thereafter, the positive external connection terminal 4 a and the negative external connection terminal 4 b were attached and sealed in the outer case 8.

次に、電解液として、リチウムフルオロボレートを０．５モル／Ｌの濃度でピロピレンカーボネートに溶解した溶液を調製した。この電解液を、外装ケース８内に注入して外装ケース８を封口し、角型の電気二重層キャパシタを得た。 Next, a solution in which lithium fluoroborate was dissolved in pyropyrene carbonate at a concentration of 0.5 mol / L was prepared as an electrolytic solution. This electrolytic solution was injected into the outer case 8 to seal the outer case 8, and a square electric double layer capacitor was obtained.

このようにして得られた電気二重層キャパシタは、図３に示したように、キャパシタ素子７と外装ケース８の内壁との間に、不要スペースが殆ど生じないので、従来の角型の電気二重層キャパシタに比較して小型となる。なお、この場合、積層一体化した電流取出部の厚さは、０．５ｍｍを超えることはなく、これによって生じるスペースは僅かであり、押し潰し加工を施すことで、積層一体化した電流取出部をさらに薄くすることも可能である。 The electric double layer capacitor thus obtained has almost no unnecessary space between the capacitor element 7 and the inner wall of the outer case 8, as shown in FIG. Smaller than a multilayer capacitor. In this case, the thickness of the integrated current extraction portion does not exceed 0.5 mm, and the resulting space is very small. It is also possible to further reduce the thickness.

図４は、本発明の第２の実施例に用いるキャパシタ素子を示す図であり、図４（ａ）は斜視図、図４（ｂ）は断面の模式図である。本実施例は、集電体表面に分極性電極層を形成して積層するところまでは、第１の実施例と同様である。 4A and 4B are diagrams showing a capacitor element used in the second embodiment of the present invention, in which FIG. 4A is a perspective view and FIG. 4B is a schematic cross-sectional view. This example is the same as the first example up to the point where a polarizable electrode layer is formed and laminated on the current collector surface.

本実施例では、電流取出部を積層一体化した後、正極電流取出部３ａを、図における前方に、負極電流取出部３ｂを、図における後方に折り曲げ、絶縁体５を介在させた状態で、それぞれ集電体に沿わせるように密着させて、キャパシタ素子９とした。その後は、第１の実施例と同様に、外部接続端子を取り付けて、外装ケースへの封入、電解液の注入、封口を行って、電気二重層キャパシタとした。 In the present embodiment, after the current extraction portions are laminated and integrated, the positive current extraction portion 3a is bent forward in the figure, the negative current extraction portion 3b is bent rearward in the figure, and the insulator 5 is interposed. The capacitor elements 9 were formed in close contact with the current collectors. After that, as in the first example, an external connection terminal was attached and sealed in an outer case, injected with an electrolyte, and sealed to obtain an electric double layer capacitor.

図５は、本発明の第３の実施例に用いる、集電体とキャパシタ素子の形状を示す図で、図５（ａ）は、集電体の形状と積層状態を示す図、図５（ｂ）は、キャパシタ素子の斜視図である。本実施例は、集電体として、縦が６４ｍｍ、横が７０ｍｍで、厚さが１８μｍのアルミニウム箔を集電体として用い、第１の実施例のような切欠部を設けず、位置決め穴１４を、４箇所設けた例である。 FIG. 5 is a diagram showing the shape of the current collector and the capacitor element used in the third embodiment of the present invention. FIG. 5A is a diagram showing the shape of the current collector and the stacked state. b) is a perspective view of the capacitor element. In this embodiment, an aluminum foil having a length of 64 mm, a width of 70 mm, and a thickness of 18 μm is used as the current collector as the current collector, and the positioning hole 14 is not provided with a notch portion as in the first embodiment. Is an example in which four locations are provided.

本実施例においても、正極集電体１０ａ、負極集電体１０ｂの表面に、第１の実施例と同様にドクターブレードを用いて、正極分極性電極層、負極分極性電極層を形成し、正極電流取出部１２ａ、負極電流取出部１２ｂをそれぞれ積層一体化して、図における前方に折り曲げ、キャパシタ素子１５とした。その後、正極外部接続端子１３ａ、負極外部接続端子１３ｂを取り付けて、第１の実施例と同様に、外装ケースへの封入、電解液の注入、封口を行い、電気二重層キャパシタとした。 Also in this example, on the surfaces of the positive electrode current collector 10a and the negative electrode current collector 10b, a positive electrode polarizable electrode layer and a negative electrode polarizable electrode layer are formed using a doctor blade in the same manner as in the first example. The positive electrode current extraction part 12a and the negative electrode current extraction part 12b were laminated and integrated, and bent forward in the figure to obtain a capacitor element 15. Thereafter, the positive electrode external connection terminal 13a and the negative electrode external connection terminal 13b were attached, and in the same manner as in the first example, sealing into the outer case, injection of the electrolyte, and sealing were performed to obtain an electric double layer capacitor.

図６は、本発明の第４の実施例に用いる、集電体とキャパシタ素子の形状を示す図で、図６（ａ）は、集電体の形状と積層状態を示す図、図６（ｂ）は、キャパシタ素子の斜視図である。本実施例は、集電体として、位置決め穴の数以外は、第３の実施例に用いたのと同じアルミニウム箔を用いている。 FIG. 6 is a diagram showing the shape of the current collector and the capacitor element used in the fourth embodiment of the present invention. FIG. 6A is a diagram showing the shape of the current collector and the stacked state. b) is a perspective view of the capacitor element. In this embodiment, the same aluminum foil as that used in the third embodiment is used as the current collector except for the number of positioning holes.

そして、本実施例においては、キャパシタ素子２１の、正極電流取出部１８ａと負極電流取出部１８ｂとほぼ垂直な方向に、正極外部接続端子１９ａと負極外部接続端子１９ｂを引き出した。その後は、第１の実施例と同様にして、外装ケースへの封入、電解液の注入、封口を行って、電気二重層キャパシタとした。 In this embodiment, the positive electrode external connection terminal 19a and the negative electrode external connection terminal 19b are drawn out in a direction substantially perpendicular to the positive electrode current extraction portion 18a and the negative electrode current extraction portion 18b of the capacitor element 21. Thereafter, in the same manner as in the first example, sealing into an outer case, injection of an electrolyte, and sealing were performed to obtain an electric double layer capacitor.

以上に説明したように、本発明の角型の電気二重層キャパシタは、外装ケース内の静電容量に寄与しない、不要なスペースが極めて少ないので、従来の電気二重層キャパシタに比較して小型化が可能である。また、本発明の電気二重層キャパシタでは、電流取出部を集電体と一体化し、大面積とすることも可能なので、低抵抗化にも寄与するものである。 As described above, the rectangular electric double layer capacitor of the present invention has a very small unnecessary space that does not contribute to the capacitance in the outer case, and thus is smaller than the conventional electric double layer capacitor. Is possible. Further, in the electric double layer capacitor of the present invention, the current extraction part can be integrated with the current collector to increase the area, which contributes to a reduction in resistance.

本発明を実施するための最良の形態に係る電気二重層キャパシタのキャパシタ素子を示す図。図１（ａ）は斜視図。図１（ｂ）は断面図。The figure which shows the capacitor element of the electric double layer capacitor which concerns on the best form for implementing this invention. FIG. 1A is a perspective view. FIG.1 (b) is sectional drawing. 電流取出部を有する正負の集電体の積層状態を示す図。The figure which shows the lamination | stacking state of the positive / negative collector which has an electric current extraction part. 外部接続端子を取り付けたキャパシタ素子を、角型の外装ケースに封入した状態を、内部を透視して示した斜視図。The perspective view which showed the state which enclosed the capacitor element which attached the external connection terminal in the square-shaped exterior case, seeing through the inside. 本発明の第２の実施例に用いるキャパシタ素子の図。図４（ａ）は斜視図。図４（ｂ）は断面の模式図。The figure of the capacitor element used for the 2nd example of the present invention. FIG. 4A is a perspective view. FIG. 4B is a schematic cross-sectional view. 本発明の第３の実施例に用いる、集電体とキャパシタ素子の形状を示す図。図５（ａ）は、集電体の形状と積層状態を示す図。図５（ｂ）は、キャパシタ素子の斜視図。The figure which shows the shape of the electrical power collector and capacitor element which are used for the 3rd Example of this invention. Fig.5 (a) is a figure which shows the shape and lamination | stacking state of an electrical power collector. FIG. 5B is a perspective view of the capacitor element. 本発明の第４の実施例に用いる、集電体とキャパシタ素子の形状を示す図。図６（ａ）は、集電体の形状と積層状態を示す図。図６（ｂ）は、キャパシタ素子の斜視図。The figure which shows the shape of the electrical power collector and capacitor element which are used for the 4th Example of this invention. Fig.6 (a) is a figure which shows the shape and lamination | stacking state of an electrical power collector. FIG. 6B is a perspective view of the capacitor element. 従来の角型の電気二重層キャパシタを示す図。図７（ａ）は内部を透視した斜視図。図７（ｂ）は断面図。The figure which shows the conventional square-shaped electric double layer capacitor. FIG. 7A is a perspective view illustrating the inside. FIG. 7B is a cross-sectional view.

符号の説明Explanation of symbols

１ａ，１０ａ，１６ａ，２２ａ正極集電体
１ｂ，１０ｂ，１６ｂ，２２ｂ負極集電体
２ａ，１１ａ，１７ａ正極分極性電極層を形成する部分
２ｂ，１１ｂ，１７ｂ負極分極性電極層を形成する部分
３ａ，１２ａ，１８ａ，２３ａ正極電流取出部
３ｂ，１２ｂ，１８ｂ，２３ｂ負極電流取出部
４ａ，１３ａ，１９ａ，２４ａ正極外部接続端子
４ｂ，１３ｂ，１９ｂ，２４ｂ負極外部接続端子
５絶縁体
６，１４，２０位置決め穴
７，９，１５，２１，２５キャパシタ素子
８，２６外装ケース
２７不要スペース 1a, 10a, 16a, 22a Positive current collectors 1b, 10b, 16b, 22b Negative current collectors 2a, 11a, 17a Parts 2b, 11b, 17b forming the positive polarizable electrode layer Parts forming the negative polarizable electrode layer 3a, 12a, 18a, 23a Positive current extraction part 3b, 12b, 18b, 23b Negative current extraction part 4a, 13a, 19a, 24a Positive external connection terminal 4b, 13b, 19b, 24b Negative external connection terminal 5 Insulator 6, 14 , 20 Positioning holes 7, 9, 15, 21, 25 Capacitor elements 8, 26 Exterior case 27 Unnecessary space

Claims

表面に正極分極性電極層が形成され、正極電流取出部を有する少なくとも１枚の正極集電体と、表面に負極分極性電極層が形成され、負極電流取出部を有する少なくとも１枚の負極集電体とを、セパレータを介して積層したキャパシタ素子と、前記キャパシタ素子に含浸された電解液と、前記キャパシタ素子封入用のケースを有する電気二重層キャパシタにおいて、前記正極電流取出部と負極電流取出部とは、それぞれ前記キャパシタ素子の積層方向に垂直な方向の、対向する側に配置されて積層一体化され、絶縁体を介在させた状態で、前記キャパシタ素子の表面に沿って折り曲げられてなることを特徴とする電気二重層キャパシタ。 At least one positive electrode current collector having a positive electrode polarizable electrode layer formed on the surface and having a positive electrode current extraction part, and at least one negative electrode current collector having a negative electrode polarizable electrode layer formed on the surface and having a negative electrode current extraction part. In the electric double layer capacitor having a capacitor element laminated with a separator through a separator, an electrolytic solution impregnated in the capacitor element, and a case for enclosing the capacitor element, the positive current extraction part and the negative current extraction The portions are arranged on the opposite sides in the direction perpendicular to the stacking direction of the capacitor elements, integrated and stacked, and are bent along the surface of the capacitor element with an insulator interposed therebetween. An electric double layer capacitor characterized by that.

前記正極電流取出部と前記負極電流取出部は、それぞれ外部接続端子が取り付けられてなることを特徴とする、請求項１に記載の電気二重層キャパシタ。 2. The electric double layer capacitor according to claim 1, wherein an external connection terminal is attached to each of the positive electrode current extraction unit and the negative electrode current extraction unit.