JP2009266873A - Capacitor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent generation of an unnecessary resistance, by increasing the strength concerning connection for leading out the electrode of a capacitor which is used in automobiles, or the like. <P>SOLUTION: A capacitor comprises current collecting boards 2 and 3 bonded, respectively, to the electrodes 1a and 1b of an element 1; a metal case 5 for containing the element 1 and having the inner base to which the negative electrode current collecting board 3, bonded to the element 1, is bonded; a terminal board 4 arranged at the opening of the metal case 5 and having the inner surface, to which the positive electrode current collecting board 2 bonded to the element 1 is bonded; and a sealing rubber 7 arranged between the terminal board 4 and the metal case 5, wherein the capacitor is configured to satisfy the relation D1<D2. Here, if the outside diameter of the element 1 is D1, the outside diameter of the current collecting boards 2 and 3 is D2; and since the outermost periphery of the element 1 surely abuts against the current collecting boards 2 and 3, high bonding strength can be ensured and generation of unwanted resistance is prevented. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a capacitor used for regeneration of various electronic devices and hybrid vehicles, or for power storage.

  FIG. 13 is a cross-sectional view showing the structure of this type of conventional capacitor, FIG. 14 is a cross-sectional view showing the structure of a pressure regulating valve provided in the capacitor, and in FIGS. 13 and 14, 20 is an element, Reference numeral 20a denotes a hollow portion, which is configured to take out the anode and the cathode from both end faces (vertical direction in FIG. 13) of the element 20, respectively.

  21 is a metal case made of aluminum containing the element 20 together with a driving electrolyte solution (not shown), 21a is a cathode terminal provided on the outer bottom surface of the metal case 21, and 21b is a protrusion provided on the inner bottom surface. The protrusion 21b is fitted into the hollow portion 20a of the element 20, and the end face on the cathode side of the element 20 is mechanically and electrically joined to the inner bottom surface of the metal case 21 by laser welding or the like.

  22 is an aluminum sealing plate, 22a is an anode terminal provided on the surface side of the sealing plate 22, 22b is a protrusion provided on the inner surface side, 22c is a hole for electrolyte injection, and the anode side of the element 20 The end surface of the metal case 21 is mechanically and electrically joined to the inner surface of the sealing plate 22 by laser welding or the like, and processed so that the opening of the metal case 21 is wound on the periphery of the sealing plate 22 (generally, curling processing and It is configured by being sealed.

  Reference numeral 23 denotes a pressure regulating valve provided on the surface side of the sealing plate 22, and as shown in detail in FIG. 14, the pressure regulating valve 23 is formed on the gas permeable member 24 on the electrolyte injection hole 22c. The closure body 25 is disposed and fixed so as to be covered with a metal cap 26 having a hole 26a communicating with the outside, thereby urging the closure body 25 in a constantly closing direction. In addition, the metal cap 26 is fixed by deforming an annular convex portion 22d previously provided on the sealing plate 22 so as to surround the periphery of the electrolyte injection hole 22c by caulking or the like. It is fixed by pressing.

  The pressure regulating valve 23 is a self-recovering type for releasing the pressure to the outside when the internal pressure of the capacitor becomes a predetermined pressure or more. The gas generated inside the capacitor is discharged to the outside to discharge the gas inside the capacitor. Since the pressure can be prevented from rising and the pressure regulating valve 23 can return to the state before the operation and maintain the airtightness inside the capacitor after the operation, the capacitor can be increased even when the pressure is increased due to gas generation inside the capacitor. The appearance is not abnormal, and the characteristics can be maintained.

  Further, the pressure regulating valve 23 is provided with a gas permeable member 24 made of a material that prevents the driving electrolyte from passing therethrough and transmits gas generated inside the capacitor to the outside. The electrolytic solution does not adhere to the closing body 25 and impair the function of the pressure regulating valve 23, and the leakage of the driving electrolytic solution to the outside of the capacitor can be prevented via the pressure regulating valve 23. .

  The conventional capacitor configured as described above can reduce the location where the driving electrolyte solution may leak by disposing and fixing the pressure regulating valve 23 in the electrolyte injection hole 22c. Therefore, a more reliable capacitor can be obtained.

As prior art document information related to the invention of this application, for example, Patent Document 1 is known.
JP 2004-134632 A

  However, in the above conventional capacitor, a pair of electrodes formed on both end surfaces of the element 20 are mechanically and electrically joined to the inner surface of the sealing plate 22 and the inner bottom surface of the metal case 21 by laser welding, respectively. Although the number of points can be reduced and the size can be reduced, the laser welding is performed by irradiating laser light from the outside of the sealing plate 22 and the metal case 21, respectively, so that it is difficult to check the welding state. In addition, there is a problem that unnecessary resistance may increase due to variations in the welding state.

  In addition, since the welding conditions are limited to a narrow range, there is a problem that it is difficult to guarantee the reliability associated with the connection for extracting the electrodes.

  An object of the present invention is to solve such a conventional problem and to provide a capacitor capable of ensuring a high level of reliability related to connection for electrode drawing and preventing generation of unnecessary resistance. It is what.

  In order to solve the above problems, the present invention provides an element, a current collector plate bonded to each electrode of the element, and a current collector plate containing the element and bonded to one electrode of the element. A metal case joined to the terminal, a current collector joined to the other electrode of the element, joined to the inner surface, a terminal plate disposed in the opening of the metal case, and between the terminal plate and the metal case It is composed of a sealing rubber that is disposed and insulated, and is compressed by a metal case for sealing. When the outer diameter of the element is D1 and the outer diameter of the current collector plate is D2, D1 <D2. Is.

  As described above, in the capacitor according to the present invention, when the outer diameter of the element is D1 and the outer diameter of the current collector plate is D2, the outermost periphery of the element surely contacts the current collector plate by the configuration of D1 <D2. As a result, the welded state is stabilized, and as a result, it is possible to obtain an effect that high joint strength can be secured and generation of unnecessary resistance can be prevented.

(Embodiment)
Hereinafter, the invention described in the entire claims of the present invention will be described by using embodiments.

  FIG. 1 is a cross-sectional view showing a configuration of a capacitor according to an embodiment of the present invention, FIG. 2 is a cross-sectional view of a main part showing a sealing portion of the capacitor, and FIG. 3 is a view of both end faces of an element used in the capacitor. 4 is a perspective view showing a state before the current collector plate is joined to the electrode, FIG. 4 is a cross-sectional view showing the state where the current collector plate is joined, and FIG. 5 is a diagram showing the terminal plate joined to the anode current collector plate of FIG. It is sectional drawing which showed the state.

  1 to 5, reference numeral 1 denotes an element, 1c denotes a hollow portion formed in the element 1, and the element 1 is a pair of positive and negative electrodes in which a polarizable electrode layer is formed on a current collector made of an aluminum foil. 1 are shifted from each other in the opposite direction and wound with a separator interposed therebetween (all not shown). From both end faces (vertical direction in FIG. 1) of the element 1, an anode 1a (in FIG. 1) is formed. The upper side and the cathode 1b (lower side in FIG. 1) are respectively taken out.

  2 is an anode current collecting plate joined to the anode 1a formed on one end face of the element 1, and 3 is a cathode current collecting plate joined to the cathode 1b similarly formed on the other end face of the element 1. The anode current collector plate 2 and the cathode current collector plate 3 are formed by processing an aluminum plate, respectively, and are superposed on the anode 1a and the cathode 1b of the element 1 and laser-welded to mechanically and electrically. It is what is joined.

  In addition, when the outer diameter of the element 1 is D1, and the outer diameters of the anode current collector plate 2 and the cathode current collector plate 3 are D2, the relationship is D1 <D2. Thus, the outermost periphery of the element 1 is surely brought into contact with the anode current collector plate 2 and the cathode current collector plate 3.

  4 is a terminal plate, 4a is a flange provided at the lower end of the terminal plate 4, and this terminal plate 4 is superimposed on the anode current collector plate 2 joined to the anode 1a of the element 1 to By laser welding from the upper surface side of the provided flange part 4a, the flange part 4a and the peripheral edge of the anode current collector plate 2 are joined mechanically and electrically. The anode 1a is taken out from the terminal plate 4.

  Further, when the outer diameter of the terminal plate 4 is set to D3 (described in FIG. 8), the outer diameter D2 of the anode current collecting plate 2 is configured to be D3≈D3. By doing so, the terminal plate 4 and the anode current collecting plate 2 are reliably in contact with each other without loss.

  Reference numeral 5 denotes an aluminum bottomed cylindrical metal case containing the element 1 to which the anode current collector plate 2, the cathode current collector plate 3 and the terminal plate 4 are joined together with a driving electrolyte (not shown). This is a joint provided by forming the inner bottom surface of the case 5 in a partially convex shape. After the element 1 is inserted into the metal case 5, the cathode current collector joined to the cathode 1 b of the element 1. The plate 3 and the joint portion 5a provided on the metal case 5 are brought into close contact with each other and laser-welded from the outer bottom surface side of the metal case 5 to be mechanically and electrically joined. 1 cathode 1b is taken out from the metal case 5.

  Further, when the inner diameter of the inner bottom surface of the metal case 5 where the cathode current collector plate 3 abuts is D4, the outer diameter of the cathode current collector plate 3 is D2 <D4. In this way, the outermost periphery of the cathode current collector plate 3 is surely brought into contact with the inner bottom surface of the metal case 5.

  The flat portion 5d formed by recessing a part of the peripheral surface on the opening side of the metal case 5 is connected to a plurality of capacitors through a connecting member (not shown) to form a metal. The case 5 is provided with a flat surface portion 5d to facilitate laser welding of the connecting member, and is not directly related to the present invention and is not indispensable.

  6 is a pressure regulating valve (details will be described later) connected so as to close the electrolyte injection hole 4b provided in the terminal plate 4, and 7 is a sealing rubber made of insulating rubber (details will be described later). Yes, with the sealing rubber 7 disposed on the upper surface of the flange 4a provided at the lower end of the terminal plate 4, the vicinity of the opening of the metal case 5 is drawn from the outer periphery (lateral groove drawing portion 5b). Thus, the sealing rubber 7 is compressed, and the opening end of the metal case 5 is curled (curling processed portion 5c) so as to press down the upper surface of the sealing rubber 7.

  6A and 6B are a plan view and a front sectional view showing the configuration of the anode current collector 2 joined to the anode 1a of the element 1, and FIGS. 7A and 7B are the same. FIG. 2 is a plan view and a front sectional view showing the configuration of the cathode current collector plate 3 bonded to the cathode 1b of the element 1, and both the anode current collector plate 2 and the cathode current collector plate 3 have a hollow portion 1c formed in the element 1. Protrusions 2a and 3a that fit into the holes are provided, and holes 2b and 3b through which the driving electrolyte solution passes are provided. It should be noted that the holes 2b and 3b through which the driving electrolyte solution passes are provided with a larger number of holes 2b in the anode current collecting plate 2 in view of injecting the driving electrolyte solution from the anode current collecting plate 2 side. It is what.

  FIGS. 8A and 8B are a plan view and a front sectional view showing the structure of an aluminum terminal plate 4 which is overlapped and joined to the anode current collector plate 2. In FIG. Is a flange provided at the lower end, 4b is a hole for injecting a driving electrolyte, 4c is a recess for mounting a pressure regulating valve 6 described later, and 4d is a projection for caulking the pressure regulating valve 6 in the same manner. .

  FIGS. 9A and 9B show an insulating rubber for sealing the opening of the metal case 5 (in this embodiment, butyl rubber is used, but the present invention is not limited to this). FIG. 9 is a plan view and a front sectional view showing the structure of an annular sealing rubber 7 made up of (a), and in FIG. 9, 7a is an annular wall provided so as to protrude from the inner periphery of the upper end, and 7b is the lower end. It is an annular wall provided so as to protrude from the outer periphery. The upper wall portion 7a thus configured is in close contact with the outer peripheral surface of the upper side of the terminal plate 4, and the lower wall portion 7b is connected to the lower side of the terminal plate 4 and the outer peripheral surface of the anode current collector plate 2. The metal case 5 is in close contact with the inner peripheral surface. The upper wall portion 7a and the lower wall portion 7b are not necessarily required for both, and may be provided only in one of the portions necessary for product design.

  FIG. 10 is a cross-sectional view showing the configuration of the pressure regulating valve 6 coupled so as to close the electrolyte injection hole 4b of the terminal plate 4. FIG. 11 is an exploded cross-sectional view of the pressure regulating valve. 10 and 11, 8 is a bottomed cylindrical stainless steel cap provided with a flange 8 a at the open end and a hole 8 b communicating with the outside, and 9 is formed in a bottomed cylindrical shape. The silicon rubber valve body, 10 is a packing made of butyl rubber, 11 is a ring washer made of aluminum in which a hole 11a is provided in the central portion, and an annular wall portion 11b is integrally provided on the periphery of the upper surface. The washer 11 is press-fitted into the cap 8 with the packing 10 and the valve body 9 placed on the inner bottom surface of the washer 11, thereby holding the valve body 9 and the packing 10 in a compressed state. This allows the valve unit Those that make up the 12.

  The press-fitting of the washer 11 into the cap 8 can be performed with high accuracy by controlling the press-fitting dimensions by using a jig (not shown). When the washer 11 is press-fitted into the cap 8, the cap 8 made of stainless steel is provided by providing a notch in the portion and providing a cut-and-raised portion 8c processed so that the notch protrudes into the cap 8. The cut-and-raised portion 8c bites into the aluminum washer 11 so that press-fitting with higher bond strength can be performed.

  13 is an aluminum washer formed in a ring shape having a hole 13a in the center, and 14 is a circular gas permeable sheet made of a porous film made of polytetrafluoroethylene (PTFE). This gas permeable sheet 14 and the washer 13 are bonded by thermal fusion using a film-like modified polypropylene (hereinafter referred to as a modified PP) 15, thereby forming a circular filter holder 16, and this filter holder 16 is connected to the terminal It is arranged above the hole 4b for electrolyte injection provided on the plate 4.

FIGS. 12A and 12B show a method of joining the washer 13 and the gas permeable sheet 14 using the modified PP 15 as shown in FIG. 12A before the thermocompression bonding. The film-like modified PP15 is placed between the washer 13 and the gas permeable sheet 14, stacked, heated for about 10 seconds at a temperature of 140 to 200 ° C., and pressed at a pressure of 1 kgf / cm ² . As shown in FIG. 12 (b), the modified PP15 melted into the gas permeable sheet 14 is uniformly infiltrated and the joining is performed by the anchor effect.

  Reference numeral 17 denotes a cylindrical butyl rubber pressing rubber formed in a reverse concave shape in cross section by providing a hole 17a in the center. The pressing rubber 17 covers the filter holder 16 and covers the filter holder 16. The gas permeable sheet 14 bonded to the substrate is pressed.

  Then, the filter holder 16 configured as described above is disposed above the electrolyte solution injection hole 4 b provided in the terminal plate 4, and is covered with the pressing rubber 17 so as to cover the filter holder 16. The valve unit 12 is disposed, and the protrusion 4d provided on the terminal plate 4 is caulked to be pressed against the flange 8a provided at the opening end of the cap 8 and mechanically coupled. The rubber 17 is held in a compressed state.

  The pressure regulating valve 6 according to the present embodiment configured as described above prevents the permeation of the driving electrolyte by the gas permeable sheet 14 when the pressure inside the capacitor rises to a predetermined pressure or higher, and only the gas The gas whose pressure has been increased pushes up the packing 10 and the valve body 9 to escape into the cap 8 from the interface between the packing 10 and the washer 11, and is released to the outside through the hole 8b provided in the cap 8. In addition, after the operation, the self-recovering type that can return to the state before the operation and maintain the airtightness inside the capacitor.

  As a result, the assembly accuracy as the valve unit 12 can be greatly improved, so that not only the operation variation as the pressure regulating valve 6 can be reduced and stable performance can be exhibited, but also the valve unit 12 can be exhibited. It is also possible to confirm the operation of the pressure regulating valve 6 as a single unit, and further, the valve body 9 is made of silicon rubber, and the valve body 9 is placed on the packing 10 made of butyl rubber. It has a special effect of being excellent in heat resistance.

  It is to be noted that such excellent heat resistance is due to the use of silicon rubber as the material of the valve body 9, but silicon rubber can exhibit excellent performance at both high and low temperatures. It is inferior to the moisture barrier property, and is solved by disposing the packing 10 made of butyl rubber on the bottom surface of the valve body 9 (inside the capacitor) for the purpose of ensuring this moisture barrier property. Is to maintain.

  Further, for the purpose of improving the operability of the pressure regulating valve 6 by improving the close contact state between the silicone rubber valve body 9 and the butyl rubber packing 10, the surface of the silicone rubber valve body 9 is polyparalyzed. It is effective by coating xylylene or the like.

  Further, by joining the valve body 9 made of silicon rubber and the packing 10 made of butyl rubber in advance using a double-sided tape or the like, workability at the time of assembly can be improved.

  Further, even if the silicon rubber valve body 9 and the butyl rubber packing 10 are not used in combination, the above-mentioned butyl rubber can be obtained by using fluorine rubber having excellent low temperature characteristics as a material for the valve body 9. It is possible to construct a pressure regulating valve only with a fluorine rubber valve body having excellent low temperature characteristics without using the packing 10 made of metal, and satisfy all of the high temperature, low temperature, and moisture barrier properties. In this case, the fluororubber having excellent low-temperature characteristics is extremely expensive, so that the practicality is low, which is not preferable.

  In the present embodiment, for the purpose of ensuring higher heat resistance, the configuration in which the valve body 9 made of silicon rubber and the packing 10 made of butyl rubber are used in combination has been described as an example. However, as long as general heat resistance is sufficient, the effects of the present invention can be sufficiently obtained even with a structure that uses only a butyl rubber valve body and no packing as in the conventional product. It is what

  As described above, in the capacitor according to the present invention, the anode current collector plate 2 and the cathode current collector plate 3 are joined to the respective electrodes 1a and 1b formed on both end faces of the element 1, and the anode current collector plate 2 is connected to the terminal. The structure in which the cathode current collector plate 3 is joined to the metal case 5 on the plate 4 makes it easy to check and inspect the joining state when the anode current collector plate 2 and the cathode current collector plate 3 are joined to the element 1. In addition, the anode current collector plate 2 can be joined to the terminal plate 4 and the cathode current collector plate 3 can be joined to the metal case 5 in a wide range of welding conditions. There is an extraordinary effect that the reliability associated with the connection for electrode extraction can be greatly improved.

  Furthermore, the outer diameter of the element 1 is D1, the outer diameter of the anode current collector plate 2 (cathode current collector plate 3) is D2, the outer diameter of the terminal plate 4 is D3, and the cathode current collector plate 3 on the inner bottom surface of the metal case 5 When the inner diameter of the contact portion is D4, the outermost periphery of the element 1 is surely in contact with the anode current collector plate 2 and the cathode current collector plate 3 by the configuration of D1 <D2, D2≈D3, and D2 <D4. Moreover, since the anode current collector plate 2 and the terminal plate 4 and the cathode current collector plate 3 and the metal case 5 are also brought into contact with each other reliably, the welding state is stabilized, and thus high bonding strength can be ensured. At the same time, it is possible to achieve a special effect that the generation of unnecessary resistance can be prevented.

  The capacitor according to the present invention has the effect of increasing the strength of connection for electrode lead-out and preventing the occurrence of unnecessary resistance, and is particularly suitable for automotive fields that require high reliability. Useful.

Sectional drawing which showed the structure of the capacitor by one embodiment of this invention Cross section of the main part showing the sealing part of the capacitor The perspective view which showed the state before joining a current collecting plate to the electrode of the both end surfaces of the element used for the capacitor Sectional drawing which showed the state which joined the current collector plate Sectional drawing which showed the state which joined the terminal plate to the anode current collecting plate of FIG. (A) The top view which showed the structure of the anode current collecting plate, (b) The front sectional view (A) The top view which showed the structure of the cathode current collecting plate, (b) The front sectional view (A) Plan view showing the configuration of the terminal board, (b) Front sectional view of the same (A) Plan view showing the configuration of the sealing rubber, (b) Front sectional view of the same Sectional view showing the configuration of the pressure regulating valve A sectional view showing the pressure regulating valve in an exploded manner (A), (b) Manufacturing process diagram showing a method of manufacturing a filter holder used for the same pressure regulating valve Sectional view showing the structure of a conventional capacitor Sectional drawing which showed the structure of the pressure regulation valve provided in the capacitor

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Element 1a Anode 1b Cathode 1c Hollow part 2 Anode current collecting plate 2a, 3a Convex part 2b, 3b, 8b, 11a, 13a Hole 3 Cathode current collecting plate 4 Terminal board 4a, 8a Eave part 4b For drive electrolyte injection Hole 4c Recess 4d Projection 5 Metal case 5a Joint 5b Lateral groove drawing part 5c Curling part 5d Flat part 6 Pressure regulating valve 7 Sealing rubber 7a, 7b, 11b Wall part 8 Cap 8c Cut-up part 9 Valve body 10 Washer 11 Washer 11 12 Valve unit 13 Washer 14 Gas permeable sheet 15 Modified PP
16 Filter holder 17 Presser rubber

Claims (3)

An element configured to take out the positive and negative electrodes from both end faces, a metal current collector plate joined to each electrode of the element, the element together with a driving electrolyte, and the element A bottomed cylindrical metal case in which a current collector plate joined to one electrode is joined to the inner bottom surface, and a current collector plate joined to the inner surface of the other electrode of the element is joined to the inner surface to open the opening of the metal case Between the outer peripheral surface of the terminal plate and the inner peripheral surface of the metal case, a terminal plate disposed on the terminal plate, a pressure adjusting valve coupled to close the electrolyte injection hole provided in the terminal plate, In a capacitor made of an annular sealing rubber that is disposed and insulated from each other and is compressed and sealed by processing a metal case, the outer diameter of the element is D1, and the outer diameter of the current collector is D2. Where D1 <D2. 2. The capacitor according to claim 1, wherein D2≈D3, where D2 is an outer diameter of the current collector plate and D3 is an outer diameter of the terminal plate. 2. The capacitor according to claim 1, wherein D2 <D4, where D2 is an outer diameter of the current collector plate and D4 is an inner diameter of a portion of the inner bottom surface of the metal case that contacts the current collector plate.

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