JP2006294721A - Electric double layer capacitor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electric double layer capacitor used for fuel-cell vehicles, etc. which is reduced in size and cost and increased in capacity. <P>SOLUTION: The electric double layer capacitor is composed of a case 2 wherein a plurality of storage chambers 2a for storing a capacitor element 1 together with an electrolyte for driving are continuously formed, and a cover 3 for sealing the top opening of the case 2. Both the case 2 and the cover 3 are formed of aluminum. By joining end faces of each capacitor element 1 to the inner bottom plane of the storage chamber 2a formed in the case 2 and the inner plane of the cover 3, the individual capacitor elements 1 are electrically connected to each other. By this structure, the number of components can be reduced, the number of assembling processes and management items can also be reduced, and thereby a cost can be reduced. Moreover, the size can be reduced while the capacity is increased by a simple structure. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an electric double layer capacitor used for regeneration of a hybrid vehicle or a fuel cell vehicle, or for storing electric power.

  FIG. 5 is a cross-sectional view showing the configuration of this type of conventional electric double layer capacitor, and FIGS. 6A and 6B are an exploded perspective view showing the configuration of a capacitor element used in the electric double layer capacitor. 5 and FIG. 6, 10a, 10b, and 10c are capacitor elements, and the capacitor elements 10a, 10b, and 10c are impregnated with a driving electrolyte solution (not shown). 11a and 11b are exposed portions of the current collector of the capacitor element 10a, and 12a, 12b, 12c and 12d are terminals for external connection connected to end surfaces of the exposed portions of the current collectors of the capacitor elements 10a, 10b and 10c. 13a, 13b, 13c, and 13d connecting plates, 14a, 14b, and 14c are capacitor element storage portions separated by partition plates 16a and 16b provided inside the outer case 15, and 17 is for sealing the outer case 15. A sealing plate 18 is a pressure regulating valve.

  Reference numeral 11 denotes a pair of electrodes constituting the capacitor element 10a (capacitor elements 10b and 10c are the same), and the pair of electrodes 11 are arranged so that the exposed portions 11a and 11b of the current collector protrude in opposite directions. The polarizable electrode layers 19a and 19b made of activated carbon, a binder, and a conductive mixture are formed, and the separator 20 is interposed between the pair of electrodes 11 thus configured. As a result, a capacitor element 10a as shown in FIG. 6B is configured.

  Thus, the conventional electric double layer capacitor is electrically joined by laser welding or the like to the connection plate 12a provided with the terminal 13a for external connection on the end face of the exposed portion 11a of one current collector of the capacitor element 10a. In addition, the connecting plate 12b is electrically joined to the end face of the exposed portion 11b of the other current collector of the capacitor element 10a by laser welding or the like, and the capacitor element 10a is impregnated with a driving electrolyte solution (not shown) 15 is accommodated in a capacitor element accommodating portion 14a separated by a partition plate 16a, and capacitor elements 10b and 10c are accommodated in capacitor element accommodating portions 14b and 14c other than the capacitor element accommodating portion 14a, respectively. External connection terminals 13b, 1c of the connection plates 12b, 12c so that the capacitor elements 10a, 10b, 10c are connected in series. By joining c, the opening of the outer case 15 is covered with the sealing plate 17, and the boundary portion is thermally welded and sealed, so that the number of parts can be further reduced. Thus, it is possible to obtain an electric double layer capacitor having low internal resistance of the capacitor elements 10a, 10b, and 10c and having high withstand voltage and high reliability.

As prior art document information related to the invention of this application, for example, Patent Document 1 is known.
JP 2003-59783 A

  However, in the conventional electric double layer capacitor, the connection plate 12a having the external connection terminals 13a is electrically joined to both end faces of each capacitor element 10a by laser welding or the like, and the external connection terminals 13a are further connected. Since it must be joined to the external connection terminal of the connection plate joined to another capacitor element, the use of the connection plate 12a provided with the external connection terminal 13a increases the number of parts and the number of manufacturing steps. In addition, there is a problem that the cost becomes high due to many management items. Furthermore, since a space for housing the connection plate 12a is required, there is a problem that it becomes a major factor that hinders downsizing and increasing the capacity.

  An object of the present invention is to solve such a conventional problem and to provide an electric double layer capacitor capable of simultaneously achieving a reduction in size and capacity and a reduction in cost.

  In order to solve the above-mentioned problems, the present invention winds a pair of positive and negative electrodes in which a polarizable electrode layer is formed on a current collector made of a metal foil with a separator interposed therebetween, and the positive and negative electrodes are opposite to each other. A capacitor element configured to be positioned on the end surface, a bottomed open case with a plurality of storage chambers for storing the capacitor element together with a driving electrolyte, and an upper surface opening of the case The case and the cover are made of aluminum, and each end face of the capacitor element is joined to the inner bottom surface of the storage chamber provided in the case and the inner surface of the cover, respectively. This is an electrically connected configuration.

  As described above, the electric double layer capacitor according to the present invention has a configuration in which both end surfaces of the capacitor element are joined to the case and the cover, respectively, thereby reducing the number of parts and reducing the number of assembly steps and management items. As a result, it is possible to obtain an effect that the size and capacity can be increased with a simpler structure.

(Embodiment 1)
Hereinafter, the invention described in the first to third aspects of the present invention will be described using the first embodiment.

  FIG. 1 is a perspective view showing a configuration of an electric double layer capacitor according to Embodiment 1 of the present invention. In FIG. 1, 1 indicates a capacitor element, and this capacitor element 1 is formed on a current collector made of metal foil. A pair of positive and negative electrodes on which a polarizable electrode layer is formed is wound with a separator interposed therebetween, and the positive and negative electrodes are configured to be positioned on end surfaces in opposite directions.

  Reference numeral 2 denotes a case having a bottomed upper surface made of aluminum, 2a denotes a storage chamber provided in the case 2, and 2b denotes a partition for forming the storage chamber 2a. Reference numeral 3 denotes a cover made of aluminum for sealing the upper surface opening of the case 2.

  The capacitor element 1 is stored in the storage chamber 2a of the case 2 in a state impregnated with a driving electrolyte solution (not shown), and each end surface of the capacitor element 1 is used as the inner bottom surface of the storage chamber 2a and the cover 3. A plurality of capacitor elements 1 are connected to each other by mechanically and electrically joining the inner surface by means such as laser welding.

  2 (a) and 2 (b) are perspective views showing capacitor elements housed in a storage chamber 2a provided in the case 2, and are formed in a cylindrical shape as shown in FIG. 2 (a). A plurality of capacitor elements 1a are arranged in a staggered manner and stored in the storage chamber 2a, or as shown in FIG. 2B, the capacitor elements 1b formed in a track shape are stored in the storage chamber 2a. By doing so, it is possible to improve the storage efficiency in the storage chamber 2a and further reduce the size.

  The electric double layer capacitor according to the present embodiment configured as described above connects a plurality of capacitor elements 1 with a simple configuration in which the capacitor element 1 is housed and joined in a housing chamber 2a provided in the case 2. Therefore, a small and large capacity electric double layer capacitor can be realized at low cost.

  In addition, an electrode extraction portion (not shown) is provided on the inner bottom surface of each storage chamber 2 a provided in the case 2, and an electrode extraction portion (not shown) corresponding to each capacitor element 1 is provided on the inner surface of the cover 3. By connecting each end face and electrically connecting each capacitor element 1 via these electrode lead-out portions, the connection reliability can be improved. .

(Embodiment 2)
The invention according to claims 4 to 7 of the present invention will be described below with reference to the second embodiment.

  FIG. 3 is a perspective view showing the configuration of an electric double layer capacitor according to Embodiment 2 of the present invention, and FIGS. 4A to 4C are perspective views showing capacitor elements used in the electric double layer capacitor. 3 and 4, 4 is a wound capacitor element having a rectangular cross section as shown in detail in FIG. 4A, and 5 is bonded to both end faces of the capacitor element 4. A pair of terminal plates.

  Reference numeral 6 denotes a case having a bottomed upper surface made of an insulating material, 6a a storage chamber provided in the case 6, 6b a partition for forming the storage chamber 6a, and 6c communicating the storage chamber 6a. In this way, the connection holes are provided in the upper part of the partition 6b, and the terminal plates 5 joined to both end faces of the capacitor elements 4 are electrically connected (not shown) via the communication holes 6c. In addition, all the drive electrolyte solutions (not shown) filled in the respective storage chambers 6a can be made the same amount.

  7 is a cover made of an insulating material that seals the upper opening of the case 6, and 8 is a pressure regulating valve provided in the cover 7, and a capacitor element housed in a housing chamber 6 a provided in the case 6. 4 is activated when the pressure in the case 6 increases due to the heat generation of 4, so as to keep the pressure in the case 6 within a normal range.

  A balance circuit 9 is provided in a part of a connection path in which each capacitor element 4 is electrically connected to adjust the characteristic variation of each capacitor element 4.

  The capacitor element 4 includes a capacitor element 4a having a configuration wound in a cylindrical shape as shown in FIG. 4B, and a capacitor element 4b formed in a cylindrical shape as shown in FIG. 4C. By arranging a plurality of them in a staggered manner and storing them in the storage chamber 6a, the storage efficiency in the storage chamber 6a can be improved and the size can be further reduced.

  The electric double layer capacitor according to the present embodiment configured as described above can obtain the same effects as those of the electric double layer capacitor according to the first embodiment, and can communicate each storage chamber 6a provided in the case 6 with each other. By providing the communication hole 6c, the internal pressure in each storage chamber 6a is kept uniform, and the balance circuit 9 adjusts the characteristic variation of each capacitor element 4 to stably exhibit excellent performance. Will be able to.

  The electric double layer capacitor according to the present invention has the effect of reducing the number of parts, reducing the number of assembly steps and management items, and reducing the cost, and further reducing the size and increasing the capacity. This is useful for battery car regeneration.

The perspective view which showed the structure of the electric double layer capacitor by Embodiment 1 of this invention (A), (b) The perspective view which showed the capacitor | condenser element used for the same electric double layer capacitor The perspective view which showed the structure of the electric double layer capacitor by Embodiment 2 of this invention (A)-(c) The perspective view which showed the capacitor | condenser element used for the same electric double layer capacitor Sectional view showing the configuration of a conventional electric double layer capacitor (A) The development perspective view which showed the composition of the capacitor element which is used for the same electric double layer capacitor, (b) the same perspective view

Explanation of symbols

1, 1a, 1b, 4, 4a, 4b Capacitor element 2, 6 Case 2a, 6a Storage chamber 2b, 6b Partition 3, 7 Cover 5 Terminal plate 6c Communication hole 8 Pressure adjusting valve 9 Balance circuit

Claims (7)

A capacitor element in which a pair of positive and negative electrodes each having a polarizable electrode layer formed on a current collector made of a metal foil is wound with a separator interposed therebetween, and the positive and negative electrodes are positioned on opposite end faces. A case with a bottomed top surface provided with a plurality of storage chambers for storing the capacitor element together with the driving electrolyte, and a cover for sealing the upper surface opening of the case. An electric double layer capacitor in which each capacitor element housed in a storage room provided in is electrically connected. The case and the cover are made of aluminum, and each capacitor element is electrically connected by joining each end face of the capacitor element to the inner bottom surface of the storage chamber provided in the case and the inner surface of the cover, respectively. Electric double layer capacitor. An electrode take-out portion is provided on the inner bottom surface of each storage chamber provided in the case, and an electrode take-out portion corresponding to each capacitor element is provided on the inner surface of the cover to connect each end face of the capacitor element. The electric double layer capacitor according to claim 1, wherein each capacitor element is electrically connected via each other. The electric double layer capacitor according to claim 1, wherein a terminal plate is joined to each end face of the capacitor element, and each capacitor element is electrically connected through the terminal plate. The electric double layer capacitor according to claim 1, wherein an outer shape of the capacitor element is any one of a square, a rectangle, and an ellipse. 2. The electric double layer capacitor according to claim 1, wherein a plurality of capacitor elements, each of which is electrically connected, are stored in each storage chamber provided in the case. The capacitor according to claim 1, wherein a balance circuit for adjusting characteristic variation of each capacitor element is provided in a part of a connection path in which each capacitor element is electrically connected.

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