JPH08250375A - Electric double layer capacitor - Google Patents

Abstract

PURPOSE: To provide an electric double layer capacitor, which has excellent electric characteristics, prevents the separator from melting even when the capacitor is left for several minutes at a high temperature and prevents short- circuit between a pair of polarizable electrodes. CONSTITUTION: An electric double layer capacitor is provided with a pair of polarizable electrodes 11a and 11b, a separator 12 provided between the pair of polarizable electrodes, electrolyte which is impregnated into the separator 12 and the pair of polarizable electrodes 11a and 11b, a metal case 13, which stores the pair of polarizable electrodes 11a and 11b and the separator 12, and a sealing body 14 which seals the metal case 13. The separator 12 is composed of micro-porous nonwoven fabric made of polyphenylene sulfide, which is a material with excellent heat resistance.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric double layer capacitor used in various electronic devices.

[0002]

2. Description of the Related Art A conventional electric double layer capacitor of this type has a structure as shown in FIG. That is, the pair of polarizable electrodes 1a and 1b and the pair of polarizable electrodes 1
and a pair of polarizable electrodes 1a and 1b and an electrolytic solution impregnated in the separator 2, and a pair of polarizable electrodes 1a and 1b and a dish-shaped plate. A current collecting layer 5 is provided between the metal case 3 and the metal lid 4.
a and 5b are provided, and the opening of the dish-shaped metal case 3 is sealed with the metal lid 4 via the sealing body 6. Further, as the material of the separator 2, for example, in JP-A-63-190322, a microporous nonwoven fabric made of polyethylene or polypropylene is used.

[0003]

However, in the above-mentioned conventional electric double layer capacitor, the separator 2 is used.
When a microporous non-woven fabric made of polyethylene or polypropylene is used as the material, if a pair of polarizable electrodes 1a and 1b are short-circuited when the separator 2 is left to stand at a high temperature of 160 ° C. or higher for several minutes. there were. As described above, the conventional electric double layer capacitor described above has a problem in that it is not very satisfactory in terms of electric characteristics.

The present invention solves the above-mentioned conventional problems, and an object of the present invention is to provide an electric double layer capacitor having excellent electric characteristics.

[0005]

In order to achieve the above object, an electric double layer capacitor of the present invention comprises a pair of polarizable electrodes, a separator interposed between the pair of polarizable electrodes, and the separator. And an electrolytic solution impregnated into the pair of polarizable electrodes, the pair of polarizable electrodes, a metal case that houses the separator, and a sealing body that seals the metal case, and the separator is heat-resistant. It is composed of a microporous nonwoven fabric made of polyphenylene sulfide, which is a rich material.

[0006]

According to the above construction, the separator of the electric double layer capacitor is made of the microporous non-woven fabric made of polyphenylene sulfide, which is a material having high heat resistance. The separator does not melt even if left alone for several minutes, which prevents the pair of polarizable electrodes from short-circuiting with each other, so that an electric double layer capacitor having excellent electric characteristics can be obtained.

[0007]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an electric double layer capacitor according to an embodiment of the present invention. 11a and 11b are a pair of polarizable electrodes 11a and 11b made of activated carbon powder and having a cylindrical shape of 4.5 mm in diameter and 1.0 mm in thickness. Then, the pair of polarizable electrodes 11a, 11
A separator 12 made of a microporous nonwoven fabric made of polyphenylene sulfide, which is a material having high heat resistance, is interposed between b. The pair of polarizable electrodes 11a and 11b and the separator 12 are impregnated with an electrolytic solution in which 10 wt% of tetraethylammonium tetrafluoroborate is dissolved in propylene carbonate.
The pair of polarizable electrodes 11a and 11b are housed in a dish-shaped metal case 13 which is a current collector, and the opening of the dish-shaped metal case 13 is covered with a sealing body 14 to collect the current. It is hermetically sealed by the metal lid 15. Further, collector layers 16a and 16b are provided between the pair of polarizable electrodes 11a and the metal lid 15 and between the polarizable electrode 11b and the dish-shaped metal case 13.

Table 1 shows an example of the present invention in which a separator 12 is a microporous non-woven fabric made of polyphenylene sulfide, and a separator is a polypropylene micro-porous non-woven fabric. The conventional example 1 and the conventional example 2 in which a microporous nonwoven fabric made of polyethylene was used for the separator each had an internal resistance and a leakage current which were electric characteristics at the initial stage and immediately after a heat resistance test at a liquid phase of 160 ° C. for 2 minutes. , Shows the average value of the capacitance.

[0010]

[Table 1]

As is clear from this (Table 1), in Conventional Example 1 and Conventional Example 2, the internal resistance was 0Ω and the leakage current was in the mA order in the electrical characteristics immediately after the heat resistance test at the liquid phase of 160 ° C. for 2 minutes. While the capacitance became 0 F, in the example of the present invention, the electrical characteristics immediately after the heat resistance test at the liquid phase of 160 ° C. for 2 minutes were not so different from the initial electrical characteristics. In the example of the present invention, the heat resistance was remarkably improved as compared with the conventional example, and therefore the liquid phase of 160 ° C.
It can be used as an electric double layer capacitor having excellent electric characteristics even when left for 2 minutes at a high temperature.

Although the coin type electric double layer capacitor has been described in the above embodiments of the present invention, the present invention is not limited to this coin type and the present invention can be applied to a wound type electric double layer capacitor. The embodiment of is applicable.

[0013]

As described above, the electric double layer capacitor of the present invention includes a pair of polarizable electrodes, a separator interposed between the pair of polarizable electrodes, and the separator and the pair of polarizable electrodes. An impregnated electrolytic solution, the pair of polarizable electrodes, a metal case containing the separator, and a sealing body for sealing the metal case, the separator,
Since it is composed of a microporous non-woven fabric made of polyphenylene sulfide, which is a material with high heat resistance, the separator will not melt even if the electric double layer capacitor is left at a high temperature of 160 ° C or higher for several minutes. This prevents the pair of polarizable electrodes from short-circuiting with each other, so that an electric double layer capacitor having excellent electric characteristics can be obtained.
It is extremely advantageous in practical use.

[Brief description of drawings]

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

FIG. 2 is a sectional view showing a conventional electric double layer capacitor.

[Explanation of symbols]

 11a, 11b Pair of polarizable electrodes 12 Separator 13 Metal case 14 Sealing body

Front page continuation (72) Inventor Masashige Ashizaki 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.

Claims (1)

[Claims] 1. A pair of polarizable electrodes, a separator interposed between the pair of polarizable electrodes, an electrolytic solution impregnated in the separator and the pair of polarizable electrodes, and the pair of polarizable electrodes. An electric double layer capacitor having a metal case for housing a separator and a sealing body for sealing the metal case, wherein the separator is made of a microporous non-woven fabric made of polyphenylene sulfide which is a material having high heat resistance.