JP2005340610A - Capacitor and manufacturing method thereof - Google Patents

Abstract

[PROBLEMS] To solve the problem that when connecting a plurality of capacitors, the anode / cathode terminal is drawn out to the opposite side and the connection space becomes large and difficult to downsize, the connection is easy and the connection space is reduced, An object is to provide a capacitor capable of reducing unnecessary resistance.
A terminal plate 4 that seals an opening of a metal case 3 that houses a capacitor element 2 includes a rib joined to one of the electrodes of the capacitor element 2 and an anode terminal piece 5 having an anode terminal 5a; The cathode terminal piece 6 provided with the cathode terminal 6 a is formed by insert molding, one of the electrodes of the capacitor element 2 is joined to the rib of the anode terminal piece 5, and the other of the electrodes is joined to the inner bottom surface of the metal case 3. In addition, since the cathode terminal piece 6 is joined to the inner peripheral surface of the metal case 3, the anode / cathode of the capacitor element 2 can be taken out from the same direction, so that the resistance can be reduced, and when a plurality of capacitors are connected. The size can be reduced by halving the connection space.
[Selection] Figure 1

Description

  The present invention relates to a capacitor used for regeneration of a hybrid car or a fuel cell car, or for storing electric power, and a method for manufacturing the same.

  FIG. 11 is a cross-sectional view showing the structure of this type of conventional capacitor. In FIG. 11, reference numeral 20 denotes a capacitor element. This capacitor element 20 has a polarizable electrode layer formed on a current collector made of aluminum foil. A pair of electrodes are wound in a direction opposite to each other and wound with a separator interposed therebetween (all not shown). From both end faces (vertical direction in FIG. 11) of the capacitor element 20, the anode and The cathode is taken out respectively.

  21 is a metal case made of aluminum containing the capacitor element 20 together with a driving electrolyte (not shown), 21a is a cathode terminal for external connection integrally provided on the bottom surface of the metal case 21, and the cathode of the capacitor element 20 The side end face is mechanically and electrically connected to the inner bottom face of the metal case 21 by means of laser welding or the like.

  22 is an aluminum lid, 22a is an anode terminal for external connection provided integrally with the lid 22, and the end face on the anode side of the capacitor element 20 is joined to the inner surface of the lid 22 by means such as laser welding. So that the peripheral edge of the lid 22 and the opening of the metal case 21 (part indicated by reference numeral 23 in FIG. 11) are wound together with an insulating member (not shown) interposed therebetween. And sealed (generally called curling).

  The conventional capacitor thus configured has a configuration in which an anode terminal 22a and a cathode terminal 21a for external connection are provided in the central axis direction (vertical direction in FIG. 11) of the metal case 21, and the anode terminal 22a and the cathode By connecting and connecting a plurality of capacitors using a connecting member 24 called a bus bar (shown in FIG. 12 to be described later), the terminal 21a is used as an on-vehicle backup power source or the like as a capacitor unit. .

For example, Patent Document 1 is known as prior art document information related to the invention of this application.
JP 2000-315632 A

  However, in the above conventional capacitor, when a plurality of capacitors are connected and used as a capacitor unit as shown in FIG. 12, when the anode terminal 22a and the cathode terminal 21a are connected, the terminals are pulled out in opposite directions. As a result, connection work is not only difficult, but connection spaces h1 and h2 are required at both ends, resulting in a problem that a large mounting space is required and the device cannot be downsized.

  Further, in order to solve this problem, as a means for pulling out the anode terminal and the cathode terminal from the same direction, lead members for external lead are respectively provided on a pair of electrodes in which a polarizable electrode layer is formed on a current collector made of aluminum foil. It is possible to draw out the anode terminal and the cathode terminal from the same direction by connecting and winding a pair of electrodes to which the lead members are connected. In order to perform electrode extraction from a plurality of locations), there is a problem that the resistance is greatly increased as compared with a configuration called end surface current collection that performs extraction from the entire end surface of the capacitor element 20. When used as a capacitor unit, there was a problem that it could not be adopted at all.

  The present invention solves such a conventional problem, and when connecting a plurality of capacitors to be used as a capacitor unit, it can be easily connected, reduces the connection space, and provides an unnecessary resistance as a capacitor. It is an object to provide a capacitor that can be extremely reduced.

  In order to solve the above problems, the present invention provides a capacitor in which a capacitor element is housed in a metal case together with a driving electrolyte, and the opening of the metal case is sealed with a terminal plate. Insulate the first terminal piece having the ribs joined to one of the electrodes positioned in opposite directions and the terminal for external connection, and the second terminal piece having the terminal for external connection in a non-contact state. One of the electrodes of the capacitor element located in opposite directions of the capacitor element is joined to the rib of the first terminal piece provided on the terminal plate, and the other electrode is connected to the metal case. And a second terminal piece provided on the terminal plate is joined to the inner peripheral surface of the metal case so that the anode / cathode of the capacitor element is taken out from the terminal plate. It is of configuration that was performed in connection for the terminal.

  As described above, the capacitor according to the present invention can be taken out directly from the end face of the element without using a lead member or the like for taking out the anode / cathode from the capacitor element. Since the cathode can be taken out from the same direction, it is possible to halve the connection space between each capacitor when connecting multiple capacitors to form a capacitor unit. It is possible to obtain a special effect that it is easy to plan.

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

  FIG. 1 is a cross-sectional view showing a configuration of a capacitor according to Embodiment 1 of the present invention, FIGS. 2 to 4 are perspective views, plan views, and cross-sectional views of a terminal plate used in the capacitor, and FIG. FIG. 6 and FIG. 7 are a plan view and a perspective view of a cathode terminal piece insert-molded on the terminal plate.

  1 to 7, reference numeral 1 denotes a capacitor, 2 denotes a capacitor element, and the capacitor element 2 is activated carbon and a binder so that an exposed portion of the current collector is formed on one end on the current collector made of aluminum foil. Winding a pair of electrodes (not shown) formed with a polarizable electrode layer mainly composed of an electrode with the separators (not shown) interposed between them so that the exposed portions of the current collector are opposite to each other In FIG. 1, the upper surface side is an anode and the lower surface side is a cathode.

  Reference numeral 3 denotes a bottomed cylindrical metal case made of aluminum. The capacitor element 2 is accommodated together with a driving electrolyte (not shown), and a protrusion 3a provided at the center of the inner bottom surface of the metal case 3 is used as a core of the capacitor element 2. The capacitor element 2 is positioned and fixed by being inserted into the cavity, which is a trace, and the rib 3b provided so as to partially protrude from the inner bottom surface of the metal case 3 and the cathode-side end face of the capacitor element 2 are laser-connected. They are mechanically and electrically connected by joining by means of welding, metal spraying, brazing and the like.

  Reference numeral 4 denotes a terminal plate. The terminal plate 4 is formed by connecting an aluminum anode terminal piece 5 having an external connection anode terminal 5a and an aluminum cathode terminal piece 6 having an external connection cathode terminal 6a. It is configured by insert molding using an insulating resin (phenol or PPS is suitable) in a contact state. Further, a driving electrolyte solution (not shown) is injected into the terminal plate 4 into the metal case 3. There is provided a safety valve mounting hole 7 (not shown, but the safety valve is mounted after injecting the driving electrolyte), and in the center of the lower surface is a hollow trace that is a core trace of the capacitor element 2. A protrusion 4a is provided for insertion into the projector.

  The anode terminal piece 5 is radially provided with groove-like ribs 5b that protrude partially downward, and the tip portions of the ribs 5b abut against the end face of the capacitor element 2 on the anode side. In this way, laser welding is performed to mechanically and electrically connect, whereby the anode of the capacitor element 2 can be taken out from the anode terminal 5a.

  Further, the cathode terminal piece 6 is provided with a joint portion 6b at the periphery thereof, and this joint portion 6b protrudes from the peripheral surface of the terminal plate 4 made of insulating resin and is exposed upward at a predetermined angle. And bent up. The joint 6b is mechanically and electrically connected to the inner peripheral surface of the metal case 3 by laser welding, whereby the cathode of the capacitor element 2 is taken out via the metal case 3 to the cathode terminal. 6a can be performed.

  When joining the joint portion 6b of the cathode terminal piece 6 to the inner peripheral surface of the metal case 3, the joining strength is improved by laser welding with a brazing material such as aluminum solder interposed in the joint portion. Reliability.

  Reference numeral 8 denotes an annular sealing rubber, and the sealing rubber 8 is fitted into the opening of the metal case 3 together with the terminal plate 4 in a state of being disposed on the peripheral edge of the upper surface of the terminal plate 4. When the vicinity is drawn and the opening end is curled and sealed, the opening end of the metal case 3 bites into the sealing rubber 8 so that reliable sealing is performed.

  In addition, when drawing the vicinity of the opening of the metal case 3 and sealing the opening end by curling, the terminal is formed by curling while the peripheral surface of the metal case 3 is pressed in the center direction. Since the joining portion 6b of the cathode terminal piece 6 provided on the plate 4 and the metal case 3 are in close contact with each other, laser welding of the joining portion 6b and the metal case 3 performed in a later process is surely performed. The reliability of bonding including strength is greatly improved.

  9 is an insulating layer applied to the inner surface of the opening end of the metal case 3, and this insulating layer 9 is driven by a capillary action of a driving electrolyte (not shown) and reacts with the sealing rubber 8 to form the sealing rubber 8. It is provided for the purpose of preventing deterioration.

  The capacitor 1 according to the present embodiment configured as described above is formed by joining the anode side end face of the capacitor element 2 to the rib 5b of the anode terminal piece 5 provided on the terminal plate 4 (generally called end face current collection). Connected to the anode terminal 5 a provided on the terminal plate 4, the cathode side end face is joined to the inner bottom face of the metal case 3 (generally called end face current collection), and the metal case 3 and the terminal board 4 are joined. By connecting the portion 6b to the cathode terminal 6a provided on the terminal plate 4 by joining the inner peripheral surface of the metal case 3 via the metal case 3, the anode / cathode extraction of the capacitor element 2 can be performed on the end surface. Since the anode side is connected to the anode terminal 5a through the anode terminal piece 5 through the anode terminal piece 5 at the shortest distance, the low-resistance capacitor that suppresses generation of unnecessary resistance as much as possible is used. In which it is possible to realize a service 1.

  Further, since the anode / cathode can be taken out from the same direction by the pair of anode terminal 5a and cathode terminal 6a provided on the terminal plate 4, a plurality of capacitors, which has been a conventional problem, are connected to form a capacitor. When used as a unit, not only is the connection work difficult because each terminal is pulled out in the opposite direction, but connection space is required at both ends, resulting in a large installation space. It will be possible to solve the problem that it cannot be miniaturized at once.

  Therefore, as shown in FIG. 8, when a plurality of capacitors 1 according to the present embodiment are connected using a bus bar 10 and used as a capacitor unit, each terminal is connected when the anode terminal 5a and the cathode terminal 6a are connected. Are drawn out in the same direction, so that not only the connection work becomes very easy, but also the connection space only needs to be h1, so that the installation space can be reduced by half and the size can be reduced. It is.

  In the present embodiment, the anode side of the capacitor element 2 is described as being connected to the anode terminal 5a provided on the terminal plate 4 and the cathode side is bonded to the metal case 3. However, the present invention is not limited to this. However, the anode and the cathode may be reversed.

  In this embodiment, the capacitor is described as an example of a cylindrical capacitor. However, the present invention is not limited to this, and the capacitor may be formed in an elliptical shape or a rectangular shape.

  Further, in the present embodiment, an example in which a plurality of ribs 5b for laser welding the anode terminal piece 5 of the terminal plate 4 is provided on the anode side end face of the capacitor element 2 has been described, but the present invention is limited to this. The rib 5b may be one, or the rib 5b may not be provided.

(Embodiment 2)
Hereinafter, the invention described in the fourth and fifth aspects of the present invention will be described using the second embodiment.

  In this embodiment, the anode / cathode bonding method of the capacitor element in the first embodiment is partially different, and other configurations are the same as those in the first embodiment. The same reference numerals are given and detailed description thereof is omitted, and only different parts will be described below with reference to the drawings.

  FIGS. 9 (a) and 9 (b) are cross-sectional views showing the principal part of the configuration of the capacitor according to the second embodiment of the present invention. In FIG. 9, 11 indicates a capacitor element, and this capacitor element 11 is a collection of aluminum foil. The anode electrode 14 in which the polarizable electrode layer 13a is formed on the surface of the electric body 12a and the cathode electrode 15 in which the polarizable electrode layer 13b is formed on the surface of the current collector 12b, which is also made of aluminum foil, are shifted in the opposite directions. In this figure, the end face portion on the anode side is viewed in an enlarged manner.

  5b is a groove-like rib provided on the anode terminal piece 5 insert-molded on the terminal plate 4, and 17 is a brazing material provided on the outer surface of the rib 5b. In this embodiment, the brazing material 17 As shown in FIG. 9A, aluminum solder (mainly composed of aluminum and silicon and having a melting point of 586 ± 6 ° C. is selected and used) is used. As shown, the anode side end face of the capacitor element 11 is brought into contact with the brazing material 17 provided on the rib 5b, and the anode of the capacitor element 11 is joined to the rib 5b by performing laser welding in this state. It is.

  Accordingly, when laser welding the aluminum constituting the anode terminal piece 5 provided with the ribs 5b and the aluminum constituting the current collector 12a, laser welding is performed with the brazing material 17 interposed therebetween, so Since the brazing material 17 having a low melting point melts at an early stage, the molten brazing material 17 wraps around the current collector 12a as shown in FIG. 9B, and the end face portion of the capacitor element 11 on the anode side As a result, it becomes possible to obtain excellent bonding strength stably, and in particular, to exert a great effect on vibration resistance.

  As a means for interposing this brazing material 17, there are methods such as dipping on the anode side end face of the capacitor element 11 or fixing to the outer surface of the rib 5 b provided on the anode terminal piece 5. As another method, for example, as shown in FIG. 10, a clad structure in which aluminum solder 18 is formed on the outer surface of the rib 5b provided on the anode terminal piece 5 can be adopted, and such a clad structure is adopted. As a result, laser welding can be performed with the aluminum solder 18 interposed only in necessary portions, so that the joining accuracy, reliability, and workability can be greatly improved.

  The description of the laser welding with the brazing filler metal 17 (or aluminum solder 18) interposed is described by taking as an example the joining between the anode side end face of the capacitor element 11 and the rib 5b provided on the anode terminal piece 5. The present invention is not limited to this, and can be similarly applied to the joining of the cathode side end face of the capacitor element 11 and the inner bottom face of the metal case 3.

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

  This embodiment is different from the first embodiment in the configuration of the capacitor element, and the other configurations are the same as those in the first embodiment. Therefore, the detailed description of the same parts is omitted, and only the different parts are described. This will be described below.

  In the capacitor element according to the present embodiment, the polarizable electrode layer constituting the electrode is formed on the entire surface of the current collector so that the exposed portion of the current collector does not remain, and the pair of polarizable electrode layers is formed. The electrode is configured by winding each electrode so that the end portions protrude in opposite directions with a separator interposed therebetween, and the capacitor element thus configured has an exposed portion of the current collector. Compared to the first embodiment in which the portion that does not contribute to the capacitance is left at one end, the polarizable electrode layer is formed on the entire surface of the current collector, so that the size and the capacity can be increased. Is.

  Further, in order to form the polarizable electrode layer on the current collector so that the exposed portion of the current collector is left at one end as in the first embodiment, mass production that produces a plurality of electrodes at once is performed. Assuming that the exposed portion (that is, the uncoated portion of the polarizable electrode layer) is formed in a striped shape on the long current collector, and the surface of the current collector Since there is a problem in terms of workability and dimensional accuracy because it must be formed in alignment with the back surface, a configuration in which a polarizable electrode layer is formed on the entire surface of the current collector as in this embodiment is used. For example, it is possible to greatly improve workability and dimensional accuracy.

(Embodiment 4)
Hereinafter, the invention described in the eleventh and twelfth aspects of the present invention will be described using the fourth embodiment.

  This embodiment is different from the first embodiment in the configuration of the capacitor element, and the other configurations are the same as those in the first embodiment. Therefore, the detailed description of the same parts is omitted, and only the different parts are described. This will be described below.

  The capacitor element in the present embodiment is such that the polarizable electrode layers formed on both end faces of the capacitor element are removed. As a specific means, both end faces of the capacitor element are set to 180 ° C. or higher. After heating, the polarizable electrode layer formed on both end faces of the capacitor element is mechanically removed. According to this method, among the activated carbon and the binder constituting the polarizable electrode layer, The binder made of CMC (carboxymethylcellulose) is thermally decomposed, so that the activated carbon can be removed very easily. For example, the activated carbon is mechanically removed using a brush or a grindstone. By removing the current collector made of aluminum foil, it becomes possible to expose the terminal plate or the like during laser welding. There is no longer a hole in the joint part of the metal case (a hole is generated when the internal pressure rises due to the gasification of the binder, which is generally called a blowhole), improving the welding strength and reliability of the joint It becomes possible to improve the property.

  As another means for removing the polarizable electrode layer formed on both end faces of the capacitor element, there is a method of mechanically removing at least a portion of the polarizable electrode layer that contacts the terminal plate and / or the metal case. More specifically, cutting is performed using a rotating grindstone or the like, and this method can also obtain the same effect as the above method.

  In the capacitor according to the present invention, the anode / cathode can be taken out from the capacitor element directly from the end face of the element without using a lead member or the like, so that the resistance can be reduced, and the anode / cathode can be taken out from the outside. Can be taken out from the same direction, so that when connecting a plurality of capacitors to form a capacitor unit, the connection space between the capacitors can be halved. It is useful for regeneration of hybrid cars and fuel cell cars, or for power storage.

Sectional drawing which showed the structure of the capacitor | condenser by Embodiment 1 of this invention Perspective view of the terminal board used for the capacitor Plan view Cross section Plan view of anode terminal piece insert-molded on the same terminal plate Plan view of cathode terminal piece insert-molded on the terminal plate Same perspective view 1 is a front view of a capacitor unit in which a plurality of capacitors according to Embodiment 1 of the present invention are connected. (A) principal part sectional drawing before joining which showed the structure of the capacitor | condenser by Embodiment 2 of this invention, (b) principal part sectional drawing after the joining Sectional drawing which shows the principal part structure of the anode terminal piece by Embodiment 2 of this invention Sectional view showing the structure of a conventional capacitor Front view of a capacitor unit with multiple conventional capacitors connected

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Capacitor 2, 11 Capacitor element 3 Metal case 3a, 4a Protrusion 3b, 5b Rib 4 Terminal board 5 Anode terminal piece 5a Anode terminal 6 Cathode terminal piece 6a Cathode terminal 6b Joint part 7 Safety valve attachment hole 8 Sealing rubber 9 Insulating layer 10 Bus bar 12a, 12b Current collector 13a, 13b Polarized electrode layer 14 Anode electrode 15 Cathode electrode 16 Separator 17 Brazing material 18 Aluminum solder

Claims (13)

A capacitor element formed by winding a pair of electrodes in which a polarizable electrode layer is formed on a current collector made of a metal foil, with positions shifted in opposite directions with a separator interposed therebetween, and the capacitor element In a capacitor having a bottomed cylindrical metal case containing a driving electrolyte and a terminal plate in which an opening of the metal case is sealed, the terminal plate is an electrode of an electrode positioned in the opposite direction of the capacitor element. Insert molding an insulating resin in a non-contact state between a first terminal piece having a rib to be joined to one side and a terminal for external connection and a second terminal piece having a terminal for external connection. One of the electrodes of the capacitor element located in opposite directions of the capacitor element is bonded to the rib of the first terminal piece provided on the terminal plate, and the other electrode is bonded to the inner bottom surface of the metal case. At the same time, the anode / cathode of the capacitor element is taken out by a pair of external connection terminals provided on the terminal plate by joining the second terminal piece provided on the terminal plate to the inner peripheral surface of the metal case. Capacitor. The peripheral edge of the second terminal piece insert-molded on the terminal board protrudes from the peripheral surface of the terminal board made of insulating resin, and the protruding part is bent upward at a predetermined angle. 1. The capacitor according to 1. The capacitor according to claim 1, wherein a rib projecting partially is provided on a joint surface between the inner bottom surface of the metal case and the capacitor element. A brazing material is interposed at the joint between the rib of the first terminal piece insert-molded on the terminal plate and one electrode of the capacitor element and / or the joint between the inner bottom surface of the metal case and the other electrode of the capacitor element. The capacitor according to claim 1. The bonding surface of the rib provided on the first terminal piece insert-molded on the terminal plate with one electrode of the capacitor element and / or the bonding surface of the inner bottom surface of the metal case with the other electrode of the capacitor element The capacitor according to claim 1, wherein the capacitor has a clad structure in which aluminum solder is formed on the material. The capacitor according to claim 1, wherein a brazing material is interposed at a joint portion between the peripheral edge of the second terminal piece that is insert-molded on the terminal board and protrudes from the peripheral surface of the terminal board, and the inner peripheral surface of the metal case. The capacitor according to claim 1, wherein the terminal plate is provided with a safety valve mounting hole that also serves as an electrolyte injection part. A polarizable electrode layer constituting the electrode is formed so that an exposed portion of the current collector remains on one end side of the current collector, and the pair of electrodes on which the polarizable electrode layer is formed are exposed portions of the current collector. The capacitor according to claim 1, wherein a capacitor element is formed by winding with separators interposed therebetween so that the directions are opposite to each other. A polarizable electrode layer constituting the electrode is formed on the entire surface of the current collector so as not to leave an exposed portion of the current collector, and a pair of electrodes on which the polarizable electrode layer is formed are opposite to each other. 2. The capacitor according to claim 1, wherein the capacitor element is formed by winding in a direction so as to protrude in a direction with a separator interposed therebetween. The capacitor according to claim 1, wherein an insulating treatment is applied to a metal case at a portion in contact with a sealing rubber that is disposed on the upper surface periphery of the terminal plate and sealed. 11. The polarizable electrode layer formed on both end faces of the capacitor element is mechanically removed after both end faces of the capacitor element are heated to 180 ° C. or higher. 11. Capacitor manufacturing method. The capacitor according to any one of claims 1 to 10, wherein at least a portion of the polarizable electrode layer formed on both end faces of the capacitor element that contacts the terminal plate and / or the metal case is mechanically removed. Production method. The capacitor according to any one of claims 1 to 10, wherein when the terminal plate is disposed and sealed in the opening of the metal case, the terminal plate and the metal case are subjected to curling processing. Production method.

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