JPH02248928A - Electrolyte - Google Patents

Abstract

PURPOSE:To enhance a specific electrical conductivity and and to provided the stability at a high temp. by using a quaternary ammonium salt of boric acid complex with alcoholic hydroxyl group-contg. compd. as a solute. CONSTITUTION:The quaternary ammonium salt of boric acid comflex with the alcoholic hydroxyl group-contg. compd. used as the solute of the electrolyte. The example of the quaternary ammonium salt of boric acid complex with the alcoholic hydroxyl group-contg. compd. is the salt formed between the quaternary ammonium hydroxide and the boric acid complex with a alcoholic hydroxyl group-contg. compd. The electrolyte which exhibits the high specific electrical conductivity without corroding metals and having a high thermal stability is obtd. in this way.

Description

[Detailed description of the invention] [Industrial application fields] TECHNICAL FIELD The present invention relates to electrolytes.

[Prior Art] Conventionally, quaternary ammonium salts of saturated aliphatic dicarboxylic acids have been used as electrolytes (for example, U.S. Pat. No. 4,473,864).
No. Specification).

[Problems to be Solved by the Invention] However, this material has a low specific conductivity, and there are also problems in that the specific conductivity decreases and gas is generated when left at high temperatures.

[Means for Solving the Problems] The present inventors have arrived at the present invention as a result of intensive studies aimed at creating an electrolytic solution that has a high specific conductivity and is stable at high temperatures.

That is, the present invention uses a quaternary ammonium salt of an alcoholic hydroxyl group-containing compound complex of boric acid as a solute in the electrolytic solution.

A quaternary ammonium salt of an alcoholic hydroxyl group-containing compound complex of boric acid has the general formula (1) monium; R is an alkyl or arylalkyl group which may have a hydroxyl group, an ether group, a ketone group and/or an S-containing functional group; H; n is an integer of 1 or more; Rn is the residue of the alcoholic hydroxyl group-containing compound, formula 0 -X-
A group represented by OR, (1) or a group represented by the formula; ln is an integer of 0 or 1 or more; R' is 2
Residue of a compound having 2 or more alcoholic hydroxyl groups; 2
R and/or R and R" may be combined to form a ring with B. One or more selected from the group consisting of tetravalent compounds of borosilicate I can give you salt.

Specific examples of quaternary ammonium salts of boric acid alcoholic hydroxyl group-containing compound complexes include British Patent Nos. 1 and 3.
23,312 and US Pat. No. 4,192,759, salts of alcoholic hydroxyl group-containing compound complexes of boric acid and quaternary ammonium hydroxide are mentioned.

In addition, examples of compounds in which two R and/or R and R" combine to form a ring with B include, for example, British Patent No.
Examples include those in which some or all of the boron atoms in the boric acid ester described in No. 341901 are converted into quaternary ammonium salts.

In general formula (1), the alkyl group of R has 1 carbon number
to 18 straight-chain or branched alkyl groups, such as methyl, ethyl, n-propyl, isopropyl, n-
Butyl group, hexyl group, octyl group, allyl group, propargyl group, crotyl group; cycloalkyl group such as cyclohexyl group, cyclopentyl group, methylcyclohexyl group; benzyl group as aralkyl group; hydroxyl group, ether group, ketone group, thioether Group-containing alkyl groups include furfuryl group, tetrahydrofurfuryl group,
Examples thereof include a thiophenemethyl group and the residue of an alcoholic hydroxyl group-containing compound (residue from which one hydroxyl group has been removed), which will be described later.

Residues of alcoholic hydroxyl group-containing compounds represented by R' (
Examples of alcoholic hydroxyl group-containing compounds (residues from which n hydroxyl groups have been removed) include the following.

A-1 Compound having one alcoholic hydroxyl group, carbon number 1
to 18 linear or branched saturated or unsaturated aliphatic monohydric alcohols, such as methanol, ethanol, isopropanol, n-butanol.

5ec-butanol, tert-butanol, 2-ethylhexanol, allyl alcohol, propargyl alcohol, benzyl alcohol; saturated and unsaturated alicyclic monohydric alcohols, such as cyclohexanol, methyl Schiff [1
2-hexanol, borneol, terpineol; monohydric alcohol containing an ether group with a molecular weight of 73 to 100, such as methyl cellosolve, ethyl cellosolve, butyl cellosolve, methyl calpitol, ethyl calpitol, butyl calpitol, etc., US Pat. No. 4,116,846 Polyalkylene glycol monoalkyl ethers and polyoxyalkylene monools as described in the specification; other heteroatom-containing monohydric alcohols such as 'furfuryl alcohol, tetrahydrofurfuryl alcohol,
Thiophenemethanol, 2-mercaptoethanol, 4
-Hydroxy-2-butanone, hydroxyacetone, N
- Examples include methylol acrylamide.

A-2 A compound having two or more adjacent alcoholic hydroxyl groups (in the formula, R1, R2, R3 and R4 are the same or different, and may have a hydroxyl group, an ether group and/or an S-containing functional group) Compounds having two or more adjacent alcoholic hydroxyl groups represented by alkyl or aralkyl groups, hydrogen atoms) Saturated or unsaturated aliphatic vicinal polyols, such as ethylene glycol, propylene glycol, ethyl ethylene glycol, 2,3-butane diol, pinacol, 1,2
-hexanediol, 1,2-decanediol, 1,2
-dodecanediol, serine, 1,2,4-)lyhydroxybutane, 1.2.3-hebutatriol, 1,
2.6-) Lihydroxyhexane, 1,2,3,4-tetrahydroxybutane, 1.2,7.8-octanetetrol, 5-hegycene-1,2-diol, 7-octene-1, 2-diol; sugar alcohol, e.g. Ex1
Sol, sorbitol, mannitol, glucitol; saturated, unsaturated alicyclic vicinal polyols, e.g. 1,2-
Cyclobentanediol, 1,2-cyclohexanediol, 1,2-cyclohebutanediol, inositol, 3,5-cyclohexadiene-1,2-diol; vicinal polyols containing ether groups, e.g. 3-methoxy-1
, 2-propanediol, 3-ethoxy-1゜2-propanediol, 3-propoxy-1,2-propanediol, 3-butoxy-1,2-propanediol, 3-
Examples include phenylmethoxy-1,2-propanediol, 3-cyclohexyloxy-1,2-propanediol, jigata serine, and trigata serine.

A-3 Compounds having two or more non-adjacent alcoholic hydroxyl groups Saturated, unsaturated aliphatic non-adjacent polyols, such as ditrimethylene glycol, 1,3-butanediol, 1,4-
Butanediol, 2,4-bentanediol, 1,5-
Bentanediol, neopentyl glycol, 1,6-
Hexanediol, 2,5-hexanediol, 2-methyl-1,3-pentanediol, hexylene glycol, 2゜2-dimethylolbutane, 2,4-hebutanediol, 2-ethyl-1,3-hexane Diol, ethohexadiol, 2-ethyl-2-n-butyl-1,3
-propanediol, cis-2-butene-1,4-diol, trans-2-butene-1,4-diol, 2-
Butyne-1,4-diol, dimethylhexynediol, trimethylolpropane, pentaerythritol; non-adjacent polyols containing ether groups with a molecular weight of 120 to 10,000, such as diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, tripropylene glycol , tetrapropylene glycol, polyethylene glycol, polypropylene glycol, polybutylene glycol, or copolymers thereof; polyoxyalkylene polyols as described in U.S. Pat. No. 4,116,846; saturated, unsaturated alicyclic non-adjacent polyols, such as 1, 4-cyclohexanediol, cyclohexane-1,3,5-triol, 4-
Cyclohexene-1,3-diol; S-containing polyols, such as thiodiethylene glycol, 2,2'-(decamethylene dithio) dimethatool; molecular weight 272 to 4
5000 polyhydroxyethyl methacrylate, molecular weight 90 to 45000 vinyl alcohol, molecular weight 18
Examples include polymers and copolymers of monomers having alcoholic hydroxyl groups, such as vinyl alcohol-hydroxyethyl methacrylate copolymers having a molecular weight of 1 to 45,000.

Two or more of these alcoholic hydroxyl group-containing compounds can be used in combination, for example, A-1 and A-2 and/or A-3.

Examples of R' include residues obtained by removing two hydroxyl groups from the two or more alcoholic hydroxyl group-containing compounds listed in A-2 and A-3 above.

Examples of the group in which two R's and/or R and R' are bonded include the same groups as R'.

Examples of compounds that combine to form a ring together with B include those shown by the formula.

In the general formula (1), n is usually 1 to 8 or more, preferably 1 to 3, and m is usually 0 to 10 or more, preferably 0 to 5.

Examples of quaternary ammonium salts include tetraalkyl (alkyl group usually has 1 to 12 carbon atoms) ammonium (tetramethylammonium, tetraethylammonium, tetrapropylammonium, tetrabutylammonium, methyltriethylammonium, dimethyldiethylammonium, ethyltrimethylammonium, N,N-dimethylpyrrolidinium, N,N-dimethylpiperidinium, N,N-pentamethylenepiperidinium, etc.), aryltrialkylammonium (such as phenyltrimethylammonium), cyclohexyltrialkylammonium (cyclohexyltrialkylammonium, etc.) xyltrimethylammonium, etc.)
, arylalkyltrialkylammonium (such as benzyltrimethylammonium), N,N-dealkylpiperidinium (such as N,N-dimethylpiperidinium), and mixtures thereof. Among these, preferred is tetraalkylammonium.

Particularly preferably asymmetric (all four alkyl groups are the same,
(not) tetraalkylammonium. Examples of the asymmetric tetraalkylammonium include methyltriethylammonium, dimethyldiethylammonium, and ethyltriethylammonium.

The quaternary ammonium salt of a boric acid alcoholic hydroxyl group-containing compound complex is produced, for example, by mixing a boric acid quaternary ammonium salt with an alcoholic hydroxyl group-containing compound and removing by-product water. Alternatively, for example UK patent no.
, 323,312, U.S. Pat. No. 4,192,759, and “methods of Elem
Ento Organic Chemistry
:VOLUMEIJ (A, N, NESMEYANO
V and K, A, KOCHES) IKOV: 19
67) Mixing the alcoholic hydroxyl group-containing compound complex or metal salt of boric acid produced by the method described in P311 to P356 with quaternary ammonium hydroxide, or mixing the metal with quaternary ammonium hydroxide.
It is produced by substituting grade ammonium and removing by-product water and metal compounds. The molar ratio of boric acid to alcoholic hydroxyl group-containing compound is usually 0.2 to
10. Preferably it is 0.5-5. The molar ratio of boric acid to quaternary ammonium is usually 0.5 to 1.5, preferably 0.8 to 1.2. Note that an excess of quaternary ammonium compounds such as hydroxides, alkoxides, and other acid salts may be present.

The electrolytic solution of the present invention consists of a salt and a solvent (usually an organic solvent).

Examples of this organic solvent include alcohols (monohydric alcohols (methyl alcohol, ethyl alcohol, propyl alcohol, butyl alcohol, diacetone alcohol, benzyl alcohol, amino alcohol, etc.);
Alcohols (ethyl alcohol, propylene glycol, diethylene glycol, hexylene glycol, etc.); trihydric alcohols (glycerin, etc.); hexitol, etc.), ethers (monoethers (ethylene glycol monomethyl ether, ethylene glycol diethyl ether, diethylene glycol monomethyl ether, diethylene glycol) monoethyl ether, ethylene glycol phenyl ether, etc.); diethers (ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether,
diethylene glycol diethyl ether, etc.), amides (formamides (N-methylformamide, N,
N-dimethylformamide, N-ethylformamide,
N,N-diethylformamide, etc.); Acedamotos (N-methylacetamide, N,N-dimethylacetamide, N-ethylacetamide, N,N-diethylacetamide, etc.); Propionamides (N,N-dimethylpropionamide, etc.) ); hexamethylphosphorylamide, etc.), oxazolidinones (N-methyl-2-oxazolidinone, 3,5-dimethyl-2-oxazolidinone, etc.), lactones (γ-butyrolactone, α-acetyl-γ-butyrolactone, β-butyrolactone) , γ
- valerolactone, etc., δ-valerolactone, etc.), nitriles (acetonitrile, acrylonitrile, etc.),
Dimethylphorphogicide, sulfolane, 1,3-dimethyl-2-imidazolidinone, N-methylpyrrolidone, aromatic solvents (toluene, xylene, etc.), paraffinic solvents (normal paraffin, isoparaffin, etc.), and two or more of these A mixture of Among these, preferred is a solvent mainly composed of γ-butyrolactone.

The electrolytic solution of the present invention can contain water, if necessary, to the extent that the alcoholic hydroxyl group-containing compound complex of boric acid is not hydrolyzed into boric acid. Its content is usually 5% or less, preferably 3% or less, particularly preferably 1% or less, based on the weight of the electrolyte.

In the electrolytic solution of the present invention, the content of the quaternary ammonium salt of the organic alcoholic hydroxyl group-containing compound complex of oxalic acid is as follows:
Usually 1-70%, preferably 1% based on the weight of the electrolyte
It is 0-40%.

The electrolytic solution of the present invention essentially consists of a quaternary ammonium salt of an organic alcoholic hydroxyl group-containing compound complex of oxalic acid and a solvent, but various additives may be added for the purpose of reducing leakage current and absorbing hydrogen gas. agents can be added. As additives, mention may be made of phosphoric acid derivatives, boric acid derivatives and nitro compounds.

The electrolytic solution of the present invention has common uses, such as an electrolytic solution for electrocomic display elements, an electrolytic solution for electrolytic polymerization, an electrolytic solution for batteries, an electrolytic solution for electric double layer capacitors, an electrolytic solution for electroplating, and an electrolytic solution for electrolytic polymerization. Can be used as A method of using an electrolyte for electrochromic display elements is described, for example, in US Pat. No. 4,432,612.

[Examples] Hereinafter, the present invention will be further explained with reference to Examples, but the present invention is not limited thereto. The percentages in the examples are by weight.

Example 1 Boric acid salt of methyltriethylammonium hydroxide (boric acid is 1% to methyltriethylammonium)
．． (03 molar equivalent used) 20 parts of ethylene takacol 14
．． 5 parts (2.4 molar equivalents relative to boric acid) and 7
By-product water was removed under reduced pressure of mmHg at 60° C. for 5 hours to obtain 29 parts of boric acid ethylene glycol complex methyltriethylammonium salt. An electrolytic solution was obtained by dissolving 20% by weight of boric acid ethylene glycol complex methyltriethylammonium salt in a γ-butyrolactone solvent.

Examples 2 to 5, Conventional Examples 1 to 4 Quaternary ammonium salts were obtained in the same manner as in Example 1, and Table 1
．． The electrolyte composition was adjusted to 2.

Example 6 A quaternary ammonium salt was obtained in the same manner as in Example 1, except that 1.2 molar equivalents of a 2-molar adduct of serine propylene oxide were used relative to boric acid, and the electrolytic solution composition was adjusted to the one shown in Table 1. did.

Prepare an electrolyte solution of the present invention and a comparative example electrolyte solution (25% γ-butyrolactone solution) consisting of a 25% γ-butyrolactone solution of the salt (electrolyte) shown in the present invention shown in Table-11 Table-2, Their specific conductivity (30℃, mS/c
m) was measured initially and after heat treatment (150°C, 5 hours).

In addition, the presence or absence of gas generation during heat treatment was observed. The results are shown in Table-3.

Table 3 4) Upon heat treatment at 150°C for 5 hours [Effects of the Invention] The electrolytic solution of the present invention exhibits high specific conductivity, does not corrode metals, and is highly thermally stable.

When the electrolytic solution of the present invention is used in an electrochromic display element, it does not corrode the parts of the electrochromic display element that come into contact with the electrolytic solution, and has a high specific conductivity, so it has the effect of extending the life of the electrochromic display element. has.

Claims (1)

[Scope of Claims] (1) Alcoholic hydroxyl group-containing compound complex of boric acid 4
An electrolytic solution (excluding those for electrolytic capacitors) characterized by using grade ammonium salt as a solute. (2) Alcoholic hydroxyl group-containing compound complex of boric acid 4
Class ammonium salt has the general formula (1) ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ [In the formula, all or part of X is ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ , tables, etc. may be ▼; Q^■ is quaternary ammonium; R is an alkyl or arylalkyl group that may have a hydroxyl group, ether group, ketone group and/or S-containing functional group; H; n is 1
or more; R^n is (1) a residue of an alcoholic hydroxyl group-containing compound, (2) a group represented by the formula -X-OR, (3) or the formula ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ m is an integer of 0 or 1 or more; R' is the residue of a compound having two or more alcoholic hydroxyl groups; two R and/or R and R^n combine to form a ring with B You may. ] Claim 1 is one or more salts selected from the group consisting of tetravalent boron compounds represented by
Electrolyte as described in section. (3) The electrolytic solution according to claim 1 or 2, wherein the quaternary ammonium is asymmetric quaternary ammonium. (4) The electrolytic solution according to claim 1, 2 or 3, wherein the alcoholic hydroxyl group-containing compound is a compound containing two or more adjacent alcoholic hydroxyl groups. (5) The electrolytic solution according to claim 1, 2 or 3, wherein the alcoholic hydroxyl group-containing compound is a compound containing two or more non-adjacent alcoholic hydroxyl groups.