JP2003282375A - Electric double-layer capacitor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electric double-layer capacitor, capable of preventing an electric leakage between capacitor cells. <P>SOLUTION: The capacitor comprises capacitor cells 1, in which a plurality of positive electrode bodies and negative electrode bodies and the laminate of a separator are housed in a bag-like soft case together with an electrolyte, a hard case 21, which houses the plurality of capacitor cells side by side, an insulating sheet 22 interposed between the hard case 21 and the capacitor cells 1, and insulating sheets 23 intervening between the adjoining capacitor cells. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an improvement of an electric double layer capacitor.

[0002]

2. Description of the Related Art In recent years, electric double layer capacitors, which can be charged rapidly and have a long charge / discharge cycle life, have been attracting attention as power storage devices used in, for example, hybrid vehicles and wind power generation facilities.

As an electric double layer capacitor of this type, there has been provided a capacitor module in which a plurality of capacitor cells are arranged and housed in a hard case, and this capacitor module is used together with a substrate of a control circuit as a unit.

As a conventional capacitor cell, there is one in which a laminated body in which a plurality of positive electrode bodies and a negative electrode body and a separator interposed therebetween are laminated together in an bag-like soft case together with an electrolytic solution ( JP-A-3-203311,
reference).

[0005]

However, although the bag-shaped soft case itself of the capacitor cell is formed of an insulating material, if the bag-shaped soft case is thin, the power storage of the capacitor cell increases and the hard case inside the hard case increases. There is a possibility of leakage occurring between the capacitor cells housed in. In addition,
Since the thickness of the bag-shaped soft case is limited in order to ensure moldability, there is a problem that it is difficult to sufficiently insulate the capacitor cells only by the bag-shaped soft case.

The present invention has been made in view of the above problems, and an object of the present invention is to provide an electric double layer capacitor capable of preventing leakage between capacitor cells.

[0007]

According to a first aspect of the present invention, there is provided a capacitor cell in which a laminate of a plurality of positive electrodes, negative electrodes, and separators is housed in a bag-shaped soft case together with an electrolytic solution, and between adjacent capacitor cells. And an insulating material interposed therebetween.

According to a second aspect of the present invention, in the first aspect, an insulating material is provided between the hard case and the capacitor cell.

In a third aspect of the invention, in the first or second aspect of the invention, an insulating coating layer is formed on the surface of the soft case as an insulating material.

[0010]

According to the first aspect of the present invention, the storage material of each capacitor cell is maintained by preventing the electric leakage between the capacitor cells by the insulating material interposed between the adjacent capacitor cells. In addition, it is possible to prevent the performance deterioration of the capacitor cell caused by the electric leakage.

According to the second aspect of the present invention, the insulating material interposed between the hard case and the capacitor cell prevents leakage of current between the capacitor cells, so that the stored power of each capacitor cell is maintained and It is possible to prevent the performance deterioration of the capacitor cell caused by the electric leakage.

According to the third aspect of the invention, the number of steps for assembling the capacitor module can be greatly reduced as compared with the structure in which the insulating sheets are inserted one by one between the capacitor cells.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the accompanying drawings.

As shown in FIGS. 1 and 2 (a) and 2 (b), a plurality of electric double layer capacitor cells 1 are housed side by side in a heat dissipating hard case 21 so that one capacitor module is formed. 20 is formed. In addition,
Capacitor cell 1 constituting the capacitor module 20
Is not limited to this.

FIG. 3 shows a capacitor cell 1. The capacitor cell 1 is formed by stacking a plurality of positive electrode bodies and negative electrode bodies, and a double-folded separator interposed therebetween, and the stacked body is housed in a bag-shaped soft case 5 together with an electrolytic solution.

The soft case 5 is formed by combining two flexible laminated sheets 6 and 7 into a bag shape, and has three layers of an intermediate layer of aluminum foil and a surface layer of resin sandwiching the intermediate layer. In the soft case 5, the flange portions 6a and 7a are welded to form the radiating fins 5a in the shape of a quadrangle.

As shown in FIG. 4, a heat transfer frame 15 for sandwiching the heat radiation fins 5a of the soft case 5 is provided. The heat transfer frame 15 has a U-shape extending along the three sides of the heat dissipation fin 5a.

The capacitor cells 1 are housed side by side in the heat dissipating hard case 21 via the heat transfer frame 15. The heat dissipating hard case 21 is formed of a metal having a high thermal conductivity, such as an aluminum material, and has a function of releasing the heat of each capacitor cell 1 to the outside air.

The insulating sheet 23 is sandwiched between the adjacent capacitor cells 1 and the heat transfer frame 15 so that they do not touch each other. An insulating sheet 23 is interposed between all the capacitor cells 1 so that each capacitor cell 1 is prevented from leaking electricity.

Two insulating sheets 22 and two insulating sheets 23 are interposed between the heat dissipating hard case 21 and each capacitor cell 1 as an insulating material for preventing electric leakage of each capacitor cell 1 to the metal heat dissipating hard case 21. To be dressed. The insulating sheets 22 and 23 are interposed so as to surround each capacitor cell 1 except the upper portion. The insulating sheet 22 is bent in a U shape along the inner wall surface of the heat dissipating hard case 21, and is laid on the inner wall surface of the heat dissipating hard case 21 without any gap. The insulating sheet 22 is in contact with both sides and the lower portion of the heat transfer frame 15 so that the heat transfer frame 15 does not touch the heat dissipation hard case 21. The rectangular insulating sheet 23 is interposed between the heat dissipating hard case 21 and the capacitor cell 1 and the heat transfer frame 15 arranged at both ends. The insulating sheets 22 and 23 are made of an insulating material such as polyester film.

It is also possible to interpose an insulating sheet 23 for each predetermined number of capacitor cells 1 to reduce the amount of the insulating sheet 23 used.

Further, each of the capacitor cells 1 may be housed in a bag-shaped insulating material.

The insulating sheet interposed between the heat dissipating hard case 21 and each capacitor cell 1 may be integrally formed in a bag shape.

It is also possible to form the heat dissipating hard case 21 itself from a resin having an insulating property and eliminate the insulating sheet interposed between the heat dissipating hard case 21 and each capacitor cell 1.

Further, as an insulating material for preventing electric leakage between adjacent capacitor cells 1, an insulating coating layer may be formed by applying an insulating material such as varnish on the surface of the soft case 5 of each capacitor cell 1. In this case, compared to a structure in which an insulating sheet is interposed between each capacitor cell 1,
The man-hours for assembling the capacitor module 20 can be significantly reduced.

It is obvious that the present invention is not limited to the above-mentioned embodiments and various modifications can be made within the scope of the technical idea thereof.

[Brief description of drawings]

FIG. 1 is an exploded perspective view of a capacitor module showing an embodiment of the present invention.

2A is a plan view of the capacitor module, and FIG. 2B is a side view of the capacitor module.

FIG. 3 is a perspective view of the same capacitor cell.

FIG. 4 is a perspective view of the heat transfer frame.

[Explanation of symbols]

1 Capacitor cell 5 soft cases 15 heat transfer frame 20 Capacitor module 21 Heat dissipation hard case 22,23 Insulation sheet

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Masakazu Sasaki             Saitama Prefecture Ageo City Oita Ichome Ichibanchi Nissan Di             Within Hazel Industry Co., Ltd.

Claims (3)

[Claims] 1. A capacitor cell in which a laminate of a plurality of positive electrode bodies, a negative electrode body, and a separator is housed together with an electrolytic solution in a bag-shaped soft case, a hard case in which the plurality of capacitor cells are housed side by side, An electric double layer capacitor comprising: an insulating material interposed between matching capacitor cells. 2. An electric double layer capacitor comprising an insulating material interposed between the hard case and the capacitor cell. 3. The electric double layer capacitor according to claim 1, wherein an insulating coating layer is formed on the surface of the soft case as the insulating material.