JPH0426774B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention relates to an electrolytic solution for electrolytic capacitors containing a fluorocomplex salt of piperidine or piperidine derivatives as an electrolyte in an aprotic solvent. [Prior art] Conventionally, an electrolytic solution consisting of an organic acid or its salt and a glycol solvent has been mainly used as an electrolytic solution for electrolytic capacitors for normal purposes, but in recent years the range of use for electronic devices has increased. Demand for improved capacitor performance has increased since then, and the presence of water in the electrolyte has become a major problem, and electrolytes that use aprotic solvents to replace organic acids or their salts/glycol electrolytes have attracted attention. It's on. However, the biggest problem with aprotic solvent-based electrolytes is how to obtain electrolytes with high conductivity. The main search is for carboxylic acids or their salts.
However, this goal has not yet been achieved, and efforts are still being made to obtain high conductivity by mixing solvents that react with acids such as alcohols and glycols to produce water, and even adding water to aprotic solvents. Inability to achieve sufficiently high conductivity, increase in water content,
The current situation is that the increase in electrolyte results in a lack of stability at high temperatures. Therefore, it is an object of the present invention to provide a substantially non-aqueous highly conductive electrolyte using an aprotic solvent. [Problems to be Solved by the Invention] The present inventors have developed a substantially non-aqueous solution by using an aprotic solvent and without using a solvent that reacts with acids such as alcohols and glycols to produce water. As a result of extensive research into electrolytes that provide high conductivity and are an electrolytic solution, we have found that salts of fluorocomplex acids with piperidine or piperidine derivatives are highly soluble in aprotic solvents, have a high degree of dissociation, and provide high conductivity. The present invention was achieved by discovering that the present invention can be imparted. [Means for Solving the Problems] That is, the electrolytic solution for an electrolytic capacitor according to the present invention has a general formula (In the formula, n is 0 or 1 or more, and when n is 1 or more, X is an alkyl substituent having 1 or 2 carbon atoms (in this case, n is 1 to 3), or a phenyl group (in this case, n is 1), R ₁ and R ₂ are hydrogen or carbon atoms 1 to 5
The electrolyte is characterized by containing a fluoro complex salt of piperidine or piperidine derivatives of the alkyl group (A represents BF ₄ or PF ₆ ) as an electrolyte. Examples of piperidine and piperidine derivatives to be covered by the present invention include 2-methylpiperidine, 3-
Methylpiperidine, 4-methylpiperidine, 1,
2-dimethylpiperidine, 1,4-dimethylpiperidine, 2,3-dimethylpiperidine, 2,4-
Dimethylpiperidine, 2,5-dimethylpiperidine, 2,6-dimethylpiperidine, 2,3,6-
Trimethylpupyridine, 2,4,6-trimethylpiperidine, 2-methyl-ethylpiperidine, 2
-N-methyl, N-,
N-dimethyl, N-ethyl, N,N-diethyl,
N-n propyl, N,N-dichloropropyl, N-
n-butyl, N,N-di-n-butyl, N-isobutyl, N,N-diisobutyl, N-n amyl, N,
Examples include quaternary amine-based piperidine derivatives of N-di-n-amyl, N-isoamyl, and N,N-diisoamyl. The aprotic solvents used in the electrolyte of the present invention include (1) amide solvents N-methylformamide, N,N-dimethylformamide, N-ethylformamide, N,
N-diethylformamide, N-methylacetamide, N,N-dimethylacetamide, N-
Ethylacetamide, N,N-diethylacetamide, hexamethylhostophorinamide. (2) Oxide type dimethyl sulfoxide (3) Nitrile type acetonitrile (4) Cyclic ester, amide type γ-butyrolactone, N-methyl-2-pyrrolidone ethylene carbonate, propylene carbonate, etc. are representative examples, but they are not limited to these. It's not something you can do. The fluorocomplex acids to which the present invention is applied include tetrafluoroboric acid (HBF ₄ ) and hexafluorophosphoric acid (HPF ₆ ). The electrolytic solution for an electrolytic capacitor according to the present invention is generally prepared by adding an equivalent amount of a desired piperidine or piperidine derivatives to an aqueous solution of a fluoro complex acid, and then reacting the same.
Drying under reduced pressure yields an anhydrous salt, which can be adjusted to a concentration that provides the desired conductivity by dissolving it in a solvent. [Example] The following is an example of an electrolytic solution for an electrolytic capacitor according to the present invention, in which 10% by weight of various piperidine derivatives fluoro complex acid salts based on various aprotic solvents are described.
The conductivity of the solution is shown in Table 1. As a comparative example, a conventional standard electrolytic solution (78% by weight of ethylene glycol, 12% by weight of water, 10% by weight of ammonium adipate) is shown.

【table】

【table】

[Table] Next, Table 2 shows the results of a high temperature load test (110°C, 1000 hours) at 16V 1000μF for the electrolytes of Examples 1 to 11 and Comparative Example.

〔Effect of the invention〕

According to the electrolytic solution of the present invention, it is possible to provide a non-aqueous electrolytic solution that has a high conductivity comparable to or higher than that of conventional glycols, water, and organic hydrochloric acid, and is suitable for the design field of electrolytic capacitors. It can provide a new and wide range of performance options.

Claims (1)

[Claims] 1. General formula in an aprotic solvent (In the formula, n is 0 or 1 or more, and when n is 1 or more, X is an alkyl substituent having 1 or 2 carbon atoms (in this case, n is 1 to 3), or a phenyl group (in this case, n is 1), R ₁ and R ₂ are hydrogen or carbon atoms 1 to 5
An electrolytic solution for an electrolytic capacitor, which contains a fluorocomplex salt of piperidine or piperidine derivatives (A represents BF ₄ or PF ₆ ) as an electrolyte.