JP2000269099A - Electric double-layer capacitor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electric double-layer capacitor, in which a capacitor element is firmly fixed and has a small equivalent series resistance, and a plurality of capacitor elements can be easily surely connected in series. SOLUTION: The top surface 12a of a capacitor element 12, whose top and bottom surfaces are swaged to make lead surfaces, is electrically connected to an upper lead member 15, whose outside end 15a passes through an opening closing member 13 and protrudes outward and contacts the bottom surface of an upper conductive plate 14 arranged inside the opening closing member, whereas the bottom surface 12b of the capacitor element 12 is electrically connected to a lower lead member 18, whose outside end 18b passes through the bottom portion of the case and protrudes outward, and contacts the top surface of the lower terminal plate 17 arranged at the bottom of the case. The upper and lower members and threaded on the outside ends.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to an electric double layer capacitor.

[0002]

2. Description of the Related Art As an electric double layer capacitor, for example, a dry cell type electric double layer capacitor as shown in FIGS. 9 and 10 has been proposed (JP-A-10-275751).
No.).

In this electric double layer capacitor 1, a capacitor element 2 is placed in a bottomed metal case 7. The capacitor element 2 is made of, for example, activated carbon, carbon and poly as a binder. Tetrafluoroethylene (P
TFE) is kneaded to form a sheet-like polarizable electrode 3b, 4
b is bonded to a metal foil, plate or mesh-like current collector 3c, 4c to which a lead is fixed in advance with a conductive adhesive to form electrode bodies 3 and 4, and a pair of the electrode bodies is separated. −
It is wound through the tabs 5 and 6. The capacitor element 2 is
After being impregnated with the electrolytic solution, it is placed in a bottomed metal case 7 and the opening of the case is sealed with a sealing body 8. The outside of the case 7 is covered with a sleeve 7a made of synthetic resin.

As shown in FIG. 9, the current collector 3 of the capacitor element 2
The widths of c and 4c are wider than the sheet-shaped polarizable electrodes 3b and 4b, and the protruding leads 3a and 4a are provided. The protruding leads are wound with a capacitor element when wound. (Swaging) so as to make surface contact as a lead surface. A through hole 2c is formed in the center of the capacitor element 2 in the vertical direction.

As shown in FIG. 10, the lower surface 2b of the swaged upper and lower surfaces of the capacitor element 2 is held in contact with the inner surface of the bottom surface 7b of the case 7, and the upper surface 2a extends through the sealing body 8 to the outside. And is held in contact with the inner surface 9 a of the conductive terminal plate 9.

[0006]

However, in the contact between the swaged upper surface 2a of the capacitor element 2 and the inner surface 9a of the terminal plate 9 and the contact between the lower surface 2b and the inner surface of the bottom surface 7b of the case 7, However, there is a disadvantage that the equivalent series resistance becomes large and the equivalent series resistance becomes large. Further, in such a holding and fixing method, there is a possibility that the capacitor element may move due to vibration or the like.

When a plurality of electric double layer capacitors 1 are connected in series and used in order to obtain a higher withstand voltage, the electric double layer capacitors 1 are arranged so as to be connected in the vertical direction. End 9 of the terminal plate 9 protruding outward
b are fitted in the recesses 7c of the bottom (cathode side) 7b of the adjacent upper electric double layer capacitor and positioned so as not to be displaced from each other. When the state is arranged or moved as one unit, the connection state immediately collapses, which is inconvenient to handle. Further, such fitting has a disadvantage that the equivalent series resistance increases.

An object of the present invention is to provide an electric double layer capacitor in which a capacitor element is firmly fixed to a terminal plate or the bottom of a case, has a low equivalent series resistance, and can easily and reliably connect a plurality of capacitors in series. I have.

[0009]

An electric double layer capacitor according to the present invention is characterized in that the upper and lower surfaces are swaged in a metal bottomed cylindrical case whose upper opening is sealed by an insulating sealing member. The upper surface of the capacitor element is electrically connected to an upper lead member having an outer end protruding outside through the sealing body. The lower surface of the capacitor element is in contact with the lower surface of the upper conductive plate disposed on the inner surface side, and the lower surface of the capacitor element is electrically connected to a lower lead member whose outer end penetrates the bottom of the case and protrudes outward. The upper and lower lead members are screwed to the outer ends of the upper and lower lead members in contact with the upper surface of the lower terminal plate disposed on the bottom surface of the lower terminal plate.

The upper and / or lower terminal board may be formed integrally with the lead member.

In addition, the lower terminal plate is formed integrally with the bottom of the case, or the lower terminal plate, the lower lead member and the bottom of the case are formed integrally, and the threaded outer end member projects downward. It may be provided.

The upper and / or lower terminal plate may be formed with an insertion portion to be inserted into the through hole of the capacitor element, or the upper and / or lower terminal plate may have a radially extending convex surface which is in contact with the upper or lower surface of the capacitor element. A part may be provided.

Further, the inner ends of the upper and / or lower lead members may enter the through holes of the capacitor element to fix the capacitor element.

Further, the electric double layer capacitor of the present invention
A plurality of capacitor elements are accommodated in one case in a series connection state in which the upper and lower surfaces are in contact with each other, the upper surface of the uppermost capacitor element is an upper terminal plate, and the lower surface of the lowermost capacitor element is the bottom or lower terminal of the case. It may be in contact with the plate.

[0015]

FIG. 1 is a sectional view showing an example of an electric double layer capacitor according to the present invention. An electric double layer capacitor 10 has a capacitor element 12 housed in an aluminum case 11. The upper opening is sealed by a sealing body 13. The sealing body 13 is a rubber plate 13
a and the bakelite plate 13b. The peripheral portion 11 a of the opening above the case 11 is curled to fix the sealing body 13.

The capacitor element 12 is the same as the capacitor element 2 described in the prior art with reference to FIG. 9, and has a structure in which the upper and lower surfaces are swaged, and the upper surface 12a of the capacitor element 12 has an anode lead surface. , And the lower surface 12b is a cathode lead surface. As the capacitor element, besides the wound type as shown in FIG. 9, a laminated capacitor element whose upper and lower surfaces are swaged may be used.

The upper surface (anode lead surface) 12a of the capacitor element 12 housed in the case 11 is an aluminum upper terminal plate 14 disposed below the sealing body 13.
Is in contact with the lower surface. A plurality of projections 14a (FIG. 2) are radially provided on the lower surface of the upper terminal plate 14 which is in contact with the upper surface 12a of the capacitor element 12, and these projections bite into the upper surface 12a of the swaged capacitor element 12. In addition, a reliable contact state is formed, and the capacitor element 12 is prevented from moving in the case 11 in the horizontal direction or the rotational direction about the longitudinal axis of the case.

The upper terminal plate 14 is electrically connected to a metal upper lead member 15 disposed through the sealing body 13 and is fixed to the sealing body 13 by the upper lead member 15. An outer end 15a of the upper lead member 15 protrudes outward from the sealing body 13, and a screw made of an inner screw is formed at the outer end 15a. On the other hand, the lower inner end 15b of the upper lead member 15 is a swaged and enlarged insertion portion. This insertion portion is fixed so that it does not enter the through hole 12 c (same as 2 c in FIG. 9) at the center of the capacitor element 12 and move in the case 11. Reference numeral 16 denotes a washer arranged to increase airtightness.

On the other hand, the lower surface (cathode lead surface) 12b of the capacitor element 12 is in contact with the upper surface of a lower terminal plate 17 made of aluminum disposed below the case 11. Lower surface 12b of capacitor element 12 of lower terminal plate 17
A plurality of projections 17a are radially formed on the upper surface in contact with (FIG. 3)
This convex portion 17a cuts into the swaged lower surface 12b to form a secure contact state similarly to the upper terminal plate 14, and the capacitor element 12 is moved in the case in the horizontal direction or the vertical axis of the case. It prevents movement in the direction of rotation about the center.

The lower terminal plate 17 is fixed to the bottom of the case 11 by a lower lead member 18 made of metal. The lower terminal plate 17, the lead member 18, and the bottom of the case 11 are electrically connected. The lower lead member 18 is fixedly disposed through the bottom 11b of the case 11, and the inner end 18a of the lower lead member 18 is connected to the upper lead member 15 described above.
Similarly to the inner end 15b, the capacitor element 12 is fixed so as not to enter the through hole 12c at the center of the capacitor element 12 and move in the case 11.

An outer thread is formed on the outer end 18b of the lower lead member 18. The outer screw is dimensioned to be screwed with the inner screw at the outer end 15a of the upper lead member 15 described above. Note that an inner thread may be formed at the outer end 18b of the lower lead member 18 and an outer thread may be formed at the outer end 15a of the upper lead member 15.

In order to connect a plurality of such electric double layer capacitors 10 in series, the second electric capacitor is attached to the inner thread of the outer end 15a of the upper lead member 15 on the anode side of the first electric double layer capacitor. An external screw at the outer end 18b of the lower lead member 18 on the cathode side of the multilayer capacitor is screwed in and fixed,
As shown in FIG. 4, a desired number of a plurality of pieces are connected in the vertical direction. A plurality of electric double layer capacitors 10 connected in this manner
a to 10d can be handled as one unit as a whole, and can be moved in unit units. The threaded outer end 18b of the lower lead member 18 at the lower end of the lowermost electric double layer capacitor 10d is omitted so as not to protrude unless it is necessary to further connect with another electric double layer capacitor. You may.

The upper terminal plate 14 and the lead member 15 may be formed integrally as shown in FIG. 5, or the lower terminal plate 17 may be formed integrally with the bottom of the case 11 as shown in FIG. Further, as shown in FIG. 7, the lower terminal plate 17 and the lower lead member 18 are formed integrally with the case 11, and the outer end 18b is formed.
May be separately attached as an outer end member.

Although a rivet-shaped member is used for the upper lead member 15, other members or parts other than the rivet, such as a screw, may be used.

As shown in FIG. 8A, the case 11 may be vertically long and a plurality of capacitor elements 12 may be housed in one case. In this case, in the case 11, the upper and lower surfaces of the capacitor element 12 are in direct contact with each other, the upper surface of the uppermost capacitor element is in contact with the upper terminal plate, and the lower surface of the lowermost capacitor element is in contact with the bottom or lower terminal plate of the case. ing. The electric double layer capacitor 10A containing such a plurality of capacitor elements 12 or the electric double layer capacitor 10 containing one capacitor element may be connected to each other by using screws of upper and lower lead members. Good.

[0026]

According to the present invention, the outer ends of the upper and lower lead members electrically connected to the upper and lower terminal boards, respectively, are screwed to form upper and lower leads of another electric double layer capacitor. Since the screw can be screwed together with the screw at the outer end of the member, the connection is simple and reliable, and the desired number of members can be freely connected in the longitudinal direction. Further, the plurality of electric double layer capacitors connected in this manner can be handled as one unit, and can be moved in units, which is convenient for installation and maintenance.

Further, since the electric double layer capacitors are securely connected and fixed to each other by screws, the equivalent series resistance when a plurality of electric double layer capacitors are connected in series is reduced.

Further, the upper and lower surfaces of the capacitor element, which is housed in the case and has swaged upper and lower surfaces, are provided with a plurality of radially projecting portions of the terminal plate and are in contact with the surface, and the projecting portions are swaged. Since the bite penetrates the surface to form a reliable contact state, the equivalent series resistance is reduced. Further, the convex portion cuts into the swaged surface to prevent the capacitor element from moving in the case in the horizontal direction or in the rotational direction about the vertical axis of the case.

Further, since the upper and / or lower terminal plate and the inner end of the upper and / or lead member enter the through hole at the center of the capacitor element and fix the capacitor element, the capacitor element moves in the case. do not do.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of an electric double layer capacitor of the present invention.

FIG. 2 is a cross-sectional view taken along the line AA of FIG.

FIG. 3 is a cross-sectional view as seen in the BB direction of FIG. 1;

FIG. 4 is a diagram showing a state in which electric double layer capacitors are connected.

FIG. 5 is a diagram showing another upper terminal board.

FIG. 6 is a view showing another lower terminal plate.

FIG. 7 is a view showing another lower terminal plate.

FIG. 8 is a diagram showing a state where a plurality of capacitor elements are housed in one case.

FIG. 9 is a diagram showing a swaged capacitor element.

FIG. 10 is a sectional view of a conventional electric double layer capacitor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Electric double layer capacitor 12 Capacitor element 12a Upper surface (anode lead surface) 12b Lower surface (cathode lead surface) 13 Sealing body 14 Upper terminal board 15 Upper lead member 15a Outer end 15b Inner end (insertion part) 17 Lower terminal plate 18 Lower lead member 18a Inner end 18b Outer end

Claims (8)

[Claims] A capacitor element whose upper and lower surfaces are swaged to form a lead surface is accommodated in a metal bottomed cylindrical case whose upper opening is sealed with an insulating sealing member. The upper surface of the capacitor element is in contact with the lower surface of the upper terminal plate disposed on the inner surface side of the sealing member, the outer end of which is electrically connected to the upper lead member that penetrates the sealing member and protrudes outward. The lower surface of the capacitor element is in contact with the upper surface of a lower terminal plate disposed on the bottom surface in the case, the outer end of which is electrically connected to a lower lead member that projects outward through the bottom of the case. An electric double-layer capacitor in which the outer ends of the upper and lower lead members are screwed to a size that can be screwed together. 2. The electric double layer capacitor according to claim 1, wherein the upper and / or lower terminal board is formed integrally with the lead member. 3. The electric double layer capacitor according to claim 1, wherein the lower terminal plate is formed integrally with the bottom of the case. 4. The case according to claim 1, wherein the lower terminal plate and the lower lead member are formed integrally with the bottom of the case, and a threaded outer end member is provided on the bottom surface of the case so as to protrude downward. Electric double layer capacitor. 5. The electric double layer according to claim 1, wherein a radially extending convex portion is provided on a surface of the upper and / or lower terminal plate which contacts the upper or lower surface of the capacitor element. Capacitors. 6. The electric double-layer capacitor according to claim 1, wherein an insertion portion is formed in the upper and / or lower terminal plate to enter a through hole at the center of the capacitor element. 7. The electric double layer capacitor according to claim 1, wherein the upper end and / or the inner end of the lead member enters a through hole in the center of the capacitor element. 8. A plurality of capacitor elements are housed in one case in a series connection state in which the upper and lower surfaces are in contact with each other. The upper surface of the uppermost capacitor element is an upper terminal plate, and the lower surface of the lowermost capacitor element is a case. 2. The electric double layer capacitor according to claim 1, wherein the capacitor is in contact with the bottom or lower terminal plate of the electric double layer capacitor.