JPH0711463Y2 - Multilayer electric double layer capacitor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION << Industrial Application Field >> The present invention relates to a laminated electric double layer capacitor, and more particularly to a structure of a sealing portion thereof.

<< Prior Art >> As shown in FIG. 6, a laminated electric double-layer capacitor is a current collector including an activated carbon electrode 2 vertically divided by a separator 1 and conductive sheets laminated above and below the electrode 2. 3 as a basic cell, these electrodes 2 and current collector 3
A plurality of layers are alternately laminated according to the pressure resistance, the periphery is sealed by the sealing portion 4, and the lead plate 5 made of a copper plate or the like is integrally laminated on the surface of the uppermost and lowermost collectors 3. Yes (only the lower lead plate 5 is shown in the figure), and a breakdown voltage according to the number of stacked layers can be obtained.

By the way, the structure of the sealing portion 4 of such an electric double layer capacitor is such that the outer peripheral edge of the collector 3 protruding from the peripheral edge of the polarizable electrode 2 and the outer peripheral edge of the separator 1 are sealed with PE and PP through the silicone sealant 6. The structure was such that a sealing gasket 7 made of a resin material such as butyl rubber was sandwiched in multiple stages, and the periphery thereof was solidified with a hot melt resin 8.

However, the technical problem described below has been pointed out in the structure of the sealing portion 4 as described above.

<Problems to be solved by the invention> That is, in the sealing portion 4, since the periphery is sealed by a combination of a resin and an adhesive, a gap is generated due to deformation during use, or a current collector. In some cases, the conductive sheet that composes the wrinkle has deteriorated properties due to wrinkles.

In addition, the seal strength is generally insufficient, and the electrolyte leaks when the internal pressure is applied even a little.

Furthermore, the thickness of the unit cell is determined by the thickness of the sealing portion 4, but since the sealing portion 4 is made by adhesion of resin, the dimensional accuracy is low and the assembly work is troublesome because of the wet work.

The present invention solves the above-mentioned drawbacks, and an object thereof is to provide a laminated electric double layer capacitor which is easy to assemble, has high sealing strength, and can improve reliability.

<< Means for Solving the Problems >> In order to achieve the above object, a polarizable electrode having a separator disposed in the center, and a cell composed of a sheet-shaped current collector disposed on one surface of the polarizable electrode, A plurality of the cells are laminated so that the polarizable electrodes and the current collector are alternately located, a sealing portion is provided around each cell, and a lead plate is provided on the upper and lower surfaces of the current collector. In the laminated electric double layer capacitor in which the
A plurality of synthetic resin sealing gaskets, each having a locking groove in which the outer periphery of the protruding portion of each current collector from the peripheral edge of the polarizable electrode is held, and laminated in multiple stages, and these sealing gaskets It is characterized by comprising a metal outer frame which is engaged in an irregular shape on the outer periphery of and is laminated in multiple stages.

Further, in this invention, it is possible to form a protrusion projecting on the sealing gasket over the entire circumference of the contact surface of the outer frame with the sealing gasket.

Furthermore, it is also possible to form a concavo-convex portion that fits over the entire circumference of the joint surface between the sealing gaskets.

<Operation> According to the above configuration, by filling the polarization electrode inside the sealing gasket with the sealing gasket overlaid on the peripheral edge of the current collector, and repeating the work of engaging the outer frame with the peripheral edge of the sealing gasket. , The assembly of the condenser is completed.

In the assembled state, the peripheral edge of the sealing gasket is press-fitted in a concave-convex shape with the outer frame made of metal, and the entire thickness thereof has a dimension according to the thickness of the outer frame and the number of laminated layers.

According to the structure of claim 2, the protrusion bites into the sealing gasket side during assembly.

With the structure of claim 3, the sealing gaskets are stacked and positioned.

<< Embodiment >> An embodiment of the present invention will be described in detail below with reference to the drawings.

1 and 2 show a multilayer electric double layer capacitor according to a first embodiment of the present invention.

In the figure, 10 is a disk-shaped lower lead plate made of a copper plate or the like, 12 is a current collector made of a conductive sheet, 14 is a polarizable electrode alternately laminated on the current collector 12, and 16 is a top and bottom of the electrode 14. The outer peripheries of the current collector 12 and the polarizable electrode 14 are hermetically sealed by a sealing portion 18.

The polarizable electrode 14 is a solid activated carbon impregnated with dilute sulfuric acid as an electrolytic solution.
By alternately stacking and, a pair of upper and lower current collectors 12 and electrodes 14 between them are used as a unit cell to form a multilayer electric double layer capacitor having a breakdown voltage according to the total number of the stacked layers.

The outer diameter of the current collector 12 is larger than the outer diameter of the polarizable electrode 14, the peripheral edge of which is projected to the outer peripheral side of the polarizable electrode 14, and the separator 16 is also formed to project from the outer peripheral surface of the electrode 14. The protruding ends 12a and 16a are sandwiched and fixed by the sealing portion 18.

The sealing portion 18 is a sealing gasket 20 that is stacked in multiple layers according to the number of stacked layers of the unit cell, and a metal outer member that engages the outer peripheral portion of each sealing gasket 20 in an uneven shape to tighten the sealing gasket 20 up and down. It consists of a frame 22.

Each sealing gasket 20 is a ring-shaped synthetic resin made of PP, PE, butyl rubber or the like, and the thickness thereof is about half the thickness of the unit cell, and each of the current collectors 12 is And the protruding ends 12a, 16 of the respective separators 16
The upper and lower surfaces have locking grooves 20a and 20b for locking a, and an L-shaped locking step portion 20c is formed on the outer circumference.

The locking groove 20a extends to the position where the locking step portion 20c is formed, depending on the size of the outer diameter of the current collector 12.

Then, when the sealing gaskets 20 are stacked in multiple stages with the locking grooves 20a, 2b aligned with each other, the protruding ends 12a, 16a form the grooves 20a-
While being sandwiched between 20a, 20b-20b, comb tooth-shaped irregularities in which the locking step portions 20c are aligned are formed on the outer periphery of the laminated body.

The outer frame 22 is formed in a ring shape similar to or slightly thinner than the sealing gasket 20, and has a U-shaped locking step portion 22a on its inner circumference, which engages with the locking step portion 20 in a staggered manner.
Is formed, and the locking step portion 20 of the sealing gasket 20 is formed.
By stacking while alternately engaging with c, it is assembled in a state of being fitted inside the tooth-like irregularities of the comb.

As a result, the locking stepped portion 20c of the sealing gasket 20 sandwiching the current collector 12 is sandwiched and fixed by the locking stepped portion 22a inside the outer frame 22.

Next, the assembling order in the above configuration will be described.

First, the current collector 12 is first placed on the lead plate 10, and the sealing gasket 20 is laminated on the outer periphery, and the current collector 12 is attached to the lead plate 10.
And the outer frame 22 is engaged with the outer periphery of the sealing gasket 20.

An insulating sheet (or a sealing material) 24 is interposed on the contact surface between the lead plate 10 and the outermost frame 22 at the bottom to electrically insulate the sheet.

Next, the polarizable electrode 14 is placed inside the sealing gasket 20,
The peripheral protruding end 16a of the separator 16 is sandwiched between the locking grooves 20b by stacking the separator 16 on the upper part thereof, then installing the outer frame 22 first, and then stacking the sealing gasket 20.

After that, the polarizable electrode 14 is repositioned and the current collector is placed on top of it.
12 and the sealing gasket 20 on top, and the outer frame 22
By installing, the outer periphery of the current collector 14 is held between the locking grooves 20a, and the locking step portions 20c are held by the upper and lower outer frames 22.

Thereafter, the same stacking operation is repeated until the desired withstand voltage is reached, and the lead plate is arranged on the upper surface of the current collector 12 located at the uppermost position, whereby the assembly of the stacked electric double layer capacitor is completed.

As the fastening means for the laminated outer frames 22, mechanical joining means such as screwing, clamping, or resistance welding,
They can be fixed to each other by welding means such as laser welding or ultrasonic welding, and the respective sealing portions can be hermetically sealed by the fastening pressure in the stacking direction thereof.

In addition, when laminating the sealing gasket 20, it is possible to interpose a sealing adhesive on each joint surface.

Next, FIG. 3 shows a second embodiment of the present invention in which a stepped portion 22a of the outer frame 22 is formed with a trapezoidal projection 30 over the entire circumference thereof, and the projection 30 is sealed in an assembled state. The sealing property is further improved by projecting the gasket 20 to the joint position with the locking step portion 20c.

The shape of the projection may be a projection 30a having a triangular cross section as shown in FIG. 4 (b), or a projection 30b having a semicircular cross section as shown in FIG. 4 (a) and the same effect.

Next, FIG. 5 shows a third embodiment of the present invention.
At the sandwiching position of the separator 16, a convex portion 40 is formed on the joint surface of the one sealing gasket 20 over the entire circumference thereof, and a concave portion 42 fitted to the convex portion 40 is formed on the joint surface of the other sealing gasket 20. Are formed.

The recesses 40 and the protrusions 42 are for the purpose of positioning the sealing gaskets 20 when assembling each other and improving the sealing performance in the assembled state, and when they are fitted together, a maze structure is formed, thereby extending the liquid leakage path. Can be planned.

Of course, it is also possible to form unevenness for the same purpose as described above at the sandwiching position of the current collector 12.

Further, in each of the above embodiments, the thickness of the outer frame 22 is set to be the same as the thickness of the sealing gasket 20, but the thickness is doubled, and the locking step portions that engage with the upper and lower locking step portions 20c are formed on the inner circumference. A structure projecting in the center can also be adopted.

Further, the shape can be formed not only in a cylindrical shape but also in a rectangular shape.

<Effects of the Invention> As described in detail in each of the embodiments above, in the multilayer electric double layer capacitor according to the present invention, the sealing gasket is placed inside the sealing gasket in a state where the sealing gasket is overlapped with the periphery of the current collector. By arranging the polar electrodes and repeating the work of engaging the outer frame with the peripheral edge of the sealing gasket, the assembly of the capacitor is completed, so the assembly work is simple, and the height dimension is determined by each outer frame. Therefore, the dimensional accuracy is also improved.

The outer peripheral portion of the sealing gasket in the assembled state is crimped in a concave-convex shape with the outer frame made of metal to improve the sealing property, and since the entire outer periphery is covered with metal, it becomes tough and does not deform or leak. Prevents liquids from occurring and improves reliability and durability.

Further, with the structure of claim 2, the protrusion bites into the sealing gasket side during assembly, and a stronger sealing property can be obtained.

Further, since the sealing gaskets are laminated and positioned with each other by the structure of claim 3, the assembling property can be further simplified and the sealing property at the contact surface between the both in the assembled state can be secured.

[Brief description of drawings]

FIG. 1 is a partial sectional exploded perspective view of a laminated electric double layer capacitor according to the first embodiment of the present invention, FIG. 2 is a partial sectional view showing the same assembled state, and FIG. 3 is a second embodiment of the present invention. 4 is a partial sectional view showing an assembled state according to FIG.
Is a partial sectional view showing a modified example of the second embodiment, FIG. 5 is a partial sectional view showing a third embodiment of the present invention, and FIG. 6 is a partial sectional view of a conventional laminated electric double layer capacitor. 10 ... Lead plate 12 ... Current collector 14 ... Polarizable electrode 16 ... Separator 18 ... Sealing portion 20 ... Sealing gasket 20a, 20b ... Locking groove 20c ... Locking step 22 ... Metal outer frame 30, 30a, 30b ... Projection 40 ... Projection 42 ... Recess

Front page continued (72) Creator Mitsuhiro Nakamura 5-36-11 Shimbashi, Minato-ku, Tokyo Inside Fuji Electric Chemical Co., Ltd. (72) Creator Ken Kurabayashi 6-22-10 Minamioi, Shinagawa-ku, Tokyo Isuzu Motors Ltd. Incorporated (72) Inventor Yoshinobu Tsuchiya 6-22-10 Minamioi, Shinagawa-ku, Tokyo Isuzu Motors Limited (72) Innovator Nobuyuki Osawa 6-22-10 Minamioi, Shinagawa-ku, Tokyo Isuzu Motors Co., Ltd. (72) Creator Seiichi Kido 6-22-10 Minamioi, Shinagawa-ku, Tokyo Isuzu Motors Co., Ltd.

Claims (3)

[Scope of utility model registration request] 1. A cell comprising a polarizable electrode having a separator disposed in the center and a sheet-shaped current collector disposed on one surface of the polarizable electrode, the cell being the polarizable electrode and the current collector. In a laminated electric double layer capacitor in which a plurality of layers are laminated so that and are alternately located, a sealing portion is provided around each cell, and lead plates are laminated and adhered to the surfaces of the current collectors on the upper and lower surfaces: The sealing portion has a plurality of synthetic resin sealing gaskets, each of which has a locking groove on the stacking surface on which the outer periphery of the projecting portion of each collector from the polarizable electrode periphery is sandwiched, and which is stacked in multiple stages. A multi-layer electric double-layer capacitor, comprising: a metal outer frame that is laminated in multiple stages by engaging with the outer periphery of these sealing gaskets in a concavo-convex shape. 2. The laminated electric double layer capacitor according to claim 1, wherein a projection protruding from the sealing gasket is formed over the entire circumference of a contact surface of the outer frame with respect to the sealing gasket. 3. The laminated electric double layer capacitor according to claim 1 or 2, wherein concave and convex portions that are fitted to each other are formed over the entire circumference of the contact surface between the sealing gaskets.