JPS6218018A - Electrolytic liquid for electrolytic capacitor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to an electrolytic solution for an electrolytic capacitor containing a tetrafluoroborate salt of an organic amine compound as an electrolyte in an aprotic solvent.

[Conventional technology]

Traditionally, organic acids or their salts/glycol-based pastes have been mainly used as electrolytes for electrolytic capacitors for normal purposes, but as the range of use of electronic devices has increased in recent years, there has been a demand for improved capacitor performance. As a result, the presence of water in pastes has become a major problem, and electrolytes that use aprotic solvents to replace organic acids or their salts/glycol-based pastes are attracting attention.

However, the biggest problem with aprotic solvent-based electrolytes is that
The problem lies in how to obtain an electrolytic solution with high conductivity, and for this purpose, the search is mainly focused on organic carboxylic acids or their salts that dissolve well in these aprotic solvents and have a high degree of dissociation. Although this goal can still be achieved, it is unavoidable that solvents that react with acids such as alcoholic acid and glycolic acid to generate water, and even water, must be blended with aprotic solvents to ensure high conductivity. is the current situation.

Therefore, it is an object of the present invention to provide a substantially non-aqueous highly conductive electrolyte using an aprotic solvent.

[Problem that the invention seeks to solve]

The present inventors have developed an electrolytic solution that is substantially non-aqueous and highly conductive by using an aprotic solvent and without using a solvent that reacts with acids such as alcohols and glycols to generate water. As a result of intensive research into electrolytes that give
The present invention was achieved by discovering that an organic amine salt of tetrafluoroborsane (I-113F) has high solubility in aprotic solvents, has a high degree of dissociation, and imparts high electrical conductivity.

That is, the electrolytic solution for an electrolytic capacitor according to the present invention is characterized in that it contains a tetrafluoroborate salt of an organic amine compound as an electrolyte in an aprotic solvent.

A compound group containing one or two pyridine rings is suitable as one of the organic amine compounds targeted by the present invention.

(1) One or more of the hydrogen atoms bonded to the pyridine carbon is an alkyl group, an alkenyl group (having 1 to 1 carbon atoms)
5) Pyridine compounds substituted with an aryl group (6 to 15 carbon atoms) or halogen: α-pyurine, β-pyurine, T-pyurine, 2-ethylpyridine, 3-ethylpyridine, 4-ethylpyridine, 2 -n-propylpyridine + 2-iso-propylpyridine, 2-n-octylpyridine, 2-vinylpyridine, 2-hexene-2-pyridine, 2-geranylpyridine, 2,3-dimethylpyridine, 2゜6-dimethylpyridine , 3,4-dimethylpyridine, 3-ethyl-4-methylpyridine, 4-ethyl-2-methylpyridine, 6-
Ethyl-2-methylpyridine, 2,3.4-1-dimethylpyridine, 2,3.6-drimethylpyridine, 2
゜4.5-) dimethylpyridine, 2,4.6-1
-limethylpyridine, 2-ethyl-3,5-dimethylpyridine, 2-phenylpyridine, 41-lylpyridine,
4-Mesitylpyridine, 3-chloropyridine, 3,5-
Dibromopyridine (2) Dipyridine compounds 2.2-diethyl-4,4-dipyridine 4.4-dimethyl-2,2-dipyridine (3) Alkylene group (carbon number 1
8) or an alkenylene group (having 2 to 8 carbon atoms)
Compounds with pyridine rings bonded 1.3-di(4-pyridyl)-propane.

1.2-di(4-pyridyl)-ethane, ■, 2-di(4-pyridyl)-ethylene, L6-di(4-pyridyl)-hexylene-3(4) 1 alkyl on the nitrogen atom of pyridine Base.

Quaternary amine compounds with an alkenyl group (1 to 15 carbon atoms) or an aryl group (6 to 15 carbon atoms) N-ethyl-2-bromopyridine, N-vinyl-3,5
-dimethylpyridine, N-phenyl-4-ethylpyridine, N-tolyl-4-butylpyridine Furthermore, as one of the organic amine compounds targeted by the present invention, one to four alkyl groups, alkenyl groups (
(C1 to C15) or aryl group (C6 to C15)
) and primary to quaternary amine compounds to which 1 to 3 hydrogen atoms are added are preferred.

(1) Primary amines methylamine, ethylamine, propylamine, isopropylamine, butylamine.

Amylamine, hexylamine, vinylamine, geranylamine, aniline, benzylamine (2) Secondary amines dimethylamine, diethylamine, dipropylamine,
Diisopropylamine, divinylamine, digeranylamine, diphenylamine, ditolylamine, N-methyl benzylamine (3) Tertiary amines trimethylamine, triethylamine, tripropylamine, tributylamine, trivinylamine, trigeranylamine, triphenylamine, N-dimethyl hensylamine (4) Quaternary amines tetramethylammonium, n-butylammonium,
Vinyltrimethylammonium.

Phenylammonium, phenyltrimethylammonium, tolyl 1-liethylammonium, benzyl I.limethylammonium The organic amine compound tetrafluoroborate used in the present invention is prepared by adding the same molar amount of the organic amine to an aqueous solution of tetrafluoroboric acid. The compound is added and stirred to form a salt, the reaction is controlled with pl+, and p
Let it be H6.5. After the reaction is completed, an anhydrous salt is obtained by heating and drying under reduced pressure.

The obtained anhydrous salt is used as an electrolyte solution as a 10% weight solution in a desired aprotic solvent.

The non-prone solvent used in the present invention includes (1)
Amide solvent N-methylformamide, N-dimethylformamide,
N-ethylformamide, N-diethylformamide,
N-methylacetamide, N-dimethylacetamide,
N-ethylacetamide, N-diethylacetamide.

Representative examples include hexamethylphosphorylamide (2) oxide-based dimethyl sulfoxide (3) nitrile-based acetonitrile (4) cyclic ketone-based T-butyrolactone, N-methyl-2-pyrrolidone, ethylene carbonate, propylene carbonate, etc. It is not limited.

〔Example〕

Hereinafter, as an example of the electrolytic solution for an electrolytic capacitor according to the present invention, 10% of tetrafluoroborousane (HBF'), which is an organic amine compound, in various aprotic solvents will be described.
Table 1 shows the weight capacity, conductive dust and spark voltage.

Table 2 shows the results of mounting the electrolytes of Examples 1 to 12 at 25 μF and 1 μF.

Table 2 [Results of the Invention] A non-aqueous TU electrolyte with a high TN conductivity comparable to or higher than that of conventional glycols, water, and organic acid salts, using the electrolytic IW liquid according to the present invention. It is possible to provide
It can provide a new tool in the field of design selection of electrolytic capacitors with a wide range of performance.

Claims (7)

[Claims] (1) An electrolytic solution for an electrolytic capacitor containing a tetrafluoroborate salt of an organic amine compound as an electrolyte in an aprotic solvent. (2) Organic amine compounds are compounds containing one or two pyridine rings; and primary to 4-carbon compounds in which 1 to 4 alkyl, alkenyl, or aryl groups and 1 to 3 hydrogen atoms are attached to a nitrogen atom. The electrolytic solution for an electrolytic capacitor according to claim 1, comprising an amine compound of grade 1. (3) A compound containing one or two pyridine rings is obtained by replacing one or more of the hydrogen atoms bonded to the carbon atoms of the pyridine ring with an alkyl group, an alkenyl group, an aryl group, or a halogen. Electrolyte solution for electrolytic capacitors as described in section. (4) The compound containing two pyridine rings is a dipyridyl compound, or a compound in which two pyridine rings are bonded with an alkylene group having 1 to 8 carbon atoms or an alkenylene group having 2 to 8 carbon atoms.Claim 2 Or the electrolytic solution for electrolytic capacitors according to item 3. (5) The electrolytic capacitor according to any one of claims 2 to 4, which includes a quaternary amine compound in which one alkyl group, alkenyl group, or aryl group is added to the nitrogen atom of a pyridine ring. Electrolyte for use. (6) Alkyl groups and alkenyl groups have 1 to 15 carbon atoms.
The electrolytic solution for an electrolytic capacitor according to any one of claims 2 to 5, wherein the aryl group has 6 to 15 carbon atoms. (7) Aprotic solvents are N-methylformamide, N-
Dimethylformamide, N-ethylformamide, N-
diethylformamide, N-methylacetamide, N-
Dimethylacetamide, N-ethylacetamide, N-
The electrolytic solution for an electrolytic capacitor according to claim 1, which is selected from the group of diethylacetamide, γ-butyrolactone, N-methyl-2-pyrrolidone, ethylene carbonate, propylene carbonate, dimethyl sulfoxide, acetonitrile, or a mixture thereof. .