JP2002260733A - Electrolyte for electrochemical device, its electrolyte solution or solid electrolyte and battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrolyte, electrolyte solution, or a solid electrolyte and a battery using the same with excellent cycle characteristics used for an electrochemical device such as a lithium battery, a lithium-ion battery, and an electric double-layer capacitor. SOLUTION: It is an electrolyte for an electrochemical device composed of a compound expressed in formula (1) and chemical structural formulae expressed in formula (2), formula (3), and formula (4), and an electrolyte solution or a solid electrolyte, and a battery using the above electrolyte.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrolyte, an electrolyte or a solid electrolyte exhibiting excellent cycle characteristics and used for electrochemical devices such as lithium batteries, lithium ion batteries, and electric double layer capacitors. Battery.

[0002]

2. Description of the Related Art With the development of portable equipment in recent years, electrochemical devices utilizing electrochemical phenomena such as batteries and capacitors as power sources have been actively developed. In addition, electrochemical devices other than power supplies include:
An electrochromic display (ECD) in which a color change is caused by an electrochemical reaction is given.

[0003] These electrochemical devices are generally composed of a pair of electrodes and an ionic conductor filling the space between the electrodes. The ion conductor, a solvent, and the cation (A ⁺⁾ called the electrolyte in the polymer, or a mixture thereof anions (B ^-) is obtained by dissolving a from consisting salts (AB) is used. When this electrolyte is dissolved, it dissociates into cations and anions and conducts ions. In order to obtain the ion conductivity required for the device, it is necessary that this electrolyte be dissolved in a sufficient amount in a solvent or a polymer. Actually, a substance other than water is often used as a solvent, and only a few types of electrolytes having sufficient solubility in such organic solvents and polymers are presently used. For example, as electrolytes for lithium batteries, LiClO ₄ , LiPF ₆ , LiBF ₄ , L
iAsF ₆ , LiN (SO ₂ CF ₃ ) ₂ , LiN (SO ₂ C _{2
F 5) 2, LiN (SO} 2 CF 3) (SO 2 C 4 F 9) and LiCF ₃ SO ₃ only. The cation portion is often determined by the device, such as lithium ion of a lithium battery, but the anion portion can be used if it satisfies the condition of high solubility.

[0004] As the application range of devices has been diversified, the most suitable electrolyte for each application has been sought. However, at present, optimization has reached the limit due to the small number of anions. In addition, existing electrolytes have various problems, and an electrolyte having a novel anion moiety is demanded. Specifically, ClO ₄ ion is explosive, A
sF ₆ ions are toxic and cannot be used for safety reasons. The only commercially available LiPF ₆ also has problems such as heat resistance and hydrolysis resistance. In addition, LiN (CF ₃
SO ₂ ) ₂ , LiN (SO ₂ C ₂ F ₅ ) ₂ , LiN (SO ₂ C
F ₃ ) (SO ₂ C ₄ F ₉ ) and LiCF ₃ SO ₃ are very good electrolytes because of their high stability and high ionic conductivity, but the potential was applied to the aluminum current collector in the battery. It is difficult to use because it corrodes in a state.

[0005]

[Specific means for solving the problem]
As a result of intensive studies in view of the problems of the prior art, the present inventors have found that excellent characteristics can be obtained by a system in which an electrolyte having a novel chemical structural characteristic is combined with a conventional electrolyte, and have reached the present invention.

That is, the present invention provides a compound comprising a chemical structural formula represented by the general formula (1) and a chemical structural formula represented by the general formula (2), (3) or (4). An electrolyte for an electrochemical device comprising at least one of compounds,

[0007]

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A^{q +}Is a metal ion, a hydrogen ion, or
An onium ion, M is a transition metal, group III of the periodic table,
A group IV or group V element, a is 0 to 8, b is 0 to 8,
n is 1-3, q is 1-3, and p is n / q, respectively.
L is halogen, C₁~ C_TenAn alkyl,
C₁~ C_TenAlkyl halide of C_Four~ C₂₀Ally
Le, C_Four~ C₂₀Aryl halide, or Z^ThreeR
⁶(These alkyls, alkyl halides, aryls
And aryl halides have a substituent,
It may have a B atom. ), Z¹Is O, S, NR^FourMa
Or NR^FourR^Five , Z^TwoIs O, S, NR^Four, Or NR^FourR
^Five , Z^ThreeIs O, S, NR^Four, Or NR^FourR^Five , Z¹, Z
^Two, Z^ThreeAre independent of each other and R¹Is C₁~ C₃₀Al
Kiren, C₁~ C_{Three 0}Alkylene halide, C_Four~ C₂₀
Arylene or C_Four~ C₂₀Halogenated aryle
(These alkylenes, halogenated alkylenes,
-Allene and halogenated arylene are substituted in the structure
The group may have a hetero atom. ), R^Two, R^ThreeIs it
Independent, H, halogen, C₁~ C_TenThe alkyl
Or C₁~ C_TenAlkyl halides (these alkyls)
And halogenated alkyls have substituents,
May have terror atoms. ), R^Four, R^FiveIs German
Standing, H, C₁~ C_TenAlkyl, or C_Four~ C₂₀No
Reel, R⁶Is C₁~ C _TenAlkyl, C₁~ C_TenHalo of
Alkyl genoide, C_Four~ C₂₀Aryl, C_Four~ C₂₀No ha
Arogenated aryls (these alkyls, halogenated al
Kills, aryls and aryl halides have the structure
May have a substituent and a hetero atom. )
And x, y and z are each independently 1 to 8
An electrolyte for an electrochemical device,
Device consisting of a substance dissolved in a non-aqueous solvent
Electrolyte solution or a solution in which the electrolyte is dissolved in a polymer
A solid electrolyte for an electrochemical device, and at least
Composed of a positive electrode, a negative electrode, an electrolytic solution or a solid electrolyte;
A battery comprising the electrolyte in a liquid or solid electrolyte is also provided.
It is.

The alkyl, alkylene, halogenated alkyl, halogenated alkylene, aryl, arylene, halogenated aryl, and halogenated arylene used in the present invention may have other functional groups such as a branch, a hydroxyl group and an ether bond. Including.

Hereinafter, the present invention will be described in more detail.

First, specific examples of the compound represented by formula (1) used in the present invention are shown below.

[0012]

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[0013]

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[0014]

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[0015]

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[0016]

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[0017]

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[0018]

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[0019]

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[0020]

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[0021]

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[0022]

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[0023]

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[0024]

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[0025]

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[0026]

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[0027]

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Here, lithium ion is mentioned as A ^{q +} , but as cations other than lithium ion, for example, sodium ion, potassium ion, magnesium ion, calcium ion, barium ion, cesium ion, silver ion, zinc ion, copper ion Ion, cobalt ion, iron ion, nickel ion, manganese ion, titanium ion, lead ion, chromium ion, vanadium ion, ruthenium ion, yttrium ion, lanthanoid ion, actinoid ion, tetrabutylammonium ion, tetraethylammonium ion, tetramethylammonium Ion, triethylmethylammonium ion, triethylammonium ion, pyridinium ion, imidazolium ion, hydrogen ion, tetraethylphospho Ion, tetramethyl phosphonium ion, tetraphenylphosphonium ion, triphenylsulfonium ion, triethylsulfonium ion, etc. is also used.

In consideration of applications such as electrochemical devices, lithium ions, tetraalkylammonium ions, and hydrogen ions are preferable. The valence ^q of the cation of A ^{q +} is preferably from 1 to 3. If it is larger than 3, the crystal lattice energy becomes large, so that there is a problem that it becomes difficult to dissolve in a solvent. Therefore, when solubility is required, 1 is more preferable. Similarly, the valency n of the anion is preferably from 1 to 3, and particularly preferably 1. The constant p representing the ratio of cation to anion is the ratio n of the valences of both.
/ Q inevitably determines.

The electrolyte represented by the general formula (1), which is a part of the constitution of the present invention, has an ionic metal complex structure, and the center M is a transition metal, III of the periodic table.
Selected from Group IV, IV, or V elements. Preferably,
Al, B, V, Ti, Si, Zr, Ge, Sn, Cu,
Y, Zn, Ga, Nb, Ta, Bi, P, As, Sc,
Hf or Sb, and more preferably Al, B or P. M centered on various elements
It is possible to use Al, B, V, T
i, Si, Zr, Ge, Sn, Cu, Y, Zn, Ga,
Nb, Ta, Bi, P, As, Sc, Hf, or Sb
Is relatively easy to synthesize, and in the case of Al, B or P, in addition to the ease of synthesis, low toxicity, stability,
It has excellent properties in terms of cost and all aspects.

Next, a description will be given of a ligand part which is a feature of the electrolyte (ionic metal complex) represented by the general formula (1). Hereinafter, the organic or inorganic portion bonded to M is referred to as a ligand.

[0032] L in the general formula (1), halogen, C ₁ ~
Alkyl of C _10, alkyl halide C ₁ ~C _10, C ₄
Aryl -C _20, an aryl halide of C ₄ -C _20,
Or Z ³ R ⁶ , preferably an electron-withdrawing ligand such as fluorine, fluorinated alkoxide, or fluorinated aryloxide. Z ¹ , Z ² , and Z ³ are each independently O, S, NR ⁴ , or NR ⁴ R ⁵ , and are bonded to M via these hetero atoms. Where O, S, N
It is not impossible, but it is very complicated for synthesis. As a characteristic of this compound, since it binds to the central metal M at Z ¹ and Z ² in the same ligand, these ligands form a chelate structure with M. Due to the effect of the chelate, heat resistance, chemical stability, and hydrolysis resistance of the compound are improved.

Next, R ¹ is a C ₁ -C ₃₀ alkylene,
₁ -C ₃₀ halogenated alkylene of C ₄ -C ₂₀ arylene or C ₄ -C ₂₀ halogenated arylene,, R ^2, R
³ is each independently H, halogen, C ₁ -C ₁₀ alkyl, or C ₁ -C ₁₀ halogenated alkyl, R ⁴ , R ^4
5 is each independently H, C ₁ -C ₁₀ alkyl, or C ₄ -C ₂₀ aryl, R ⁶ is C ₁ -C ₁₀ alkyl, C ₁ -C ₁₀ halogenated alkyl, C ₄ aryl -C _20, represent each a halogenated aryl of C ₄ -C _20, preferably R ^1, of R ^2, R ^3, at least one halogenated alkylene or halogenated alkyl. The alkyl, alkylene, alkyl halide, alkylene halide, aryl, arylene, aryl halide, arylene halide mentioned here are
Those having other functional groups such as a branch, a hydroxyl group, and an ether bond are also included. The presence of an electron-withdrawing alkylene halide or alkyl halide in R ¹ , R ² , and R ³ disperses the negative charge of the central M and increases the electrical stability of the anion. This increases solubility in a solvent, ionic conductivity, catalytic activity, and the like.
Further, other heat resistance, chemical stability and hydrolysis resistance are also improved. The constants a and b related to the number of ligands described above are determined by the type of M at the center, and a is preferably 0 to 8 and b is preferably 0 to 8 (however, , A and b do not become 0 at the same time.)

Next, specific examples of the compounds represented by the general formulas (2), (3) and (4) include LiCF
₃ SO ₃ , LiN (SO ₂ CF ₃ ) ₂ , LiN (SO ₂ C
_{2 F 5) 2, LiN (} SO 2 CF 3) (SO 2 C 4 F 9), and _{LiC (SO 2 CF 3) 3} , and the like. When these electrolytes are used alone, the aluminum current collector in the battery is corroded in a state where a potential is applied, so that there is a problem that the capacity is reduced when the charge / discharge cycle is repeated. In the present invention, it is possible to prevent corrosion of the aluminum current collector by using a mixture of the electrolyte having a sulfonyl group and the electrolyte of the general formula (1). Although the details of the principle are not clear, it is presumed that the electrolyte of the general formula (1) is slightly decomposed on the electrode surface to form a film made of the ligand on the aluminum surface, thereby preventing the corrosion. .

The use ratio of these electrolytes is preferably in the following range in consideration of the effect of improving the cycle characteristics and storage stability of the electrochemical device. The molar ratio of the electrolyte of the general formula (1) to the electrolytes of the general formulas (2), (3) and (4) is 1:99 to 99: 1, preferably 2
0:80 to 80:20. When the amount of the electrolyte of the general formula (1) is less than 1, the effect of preventing corrosion of aluminum is small, so that the cycle characteristics and the storage stability are deteriorated.
On the other hand, when it is larger than 99, the high ion conductivity and the electrochemical stability of the general formulas (2), (3) and (4) cannot be sufficiently exhibited.

When an electrochemical device is constructed using the electrolyte of the present invention, its basic components include an ion conductor, a negative electrode, a positive electrode, a current collector, a separator, a container, and the like.

As the ionic conductor, a mixture of an electrolyte and a non-aqueous solvent or polymer is used. If a non-aqueous solvent is used, the ionic conductor is generally called an electrolytic solution, and if a polymer is used, the ionic conductor is called a polymer solid electrolyte. Polymer solid electrolytes include those containing a non-aqueous solvent as a plasticizer.

The non-aqueous solvent is not particularly limited as long as it is an aprotic solvent capable of dissolving the electrolyte of the present invention. Examples thereof include carbonates, esters, ethers, lactones, nitriles, amides and the like. , Sulfones and the like can be used. Further, not only a single solvent but also a mixed solvent of two or more kinds may be used. Specific examples include propylene carbonate, ethylene carbonate, diethyl carbonate, dimethyl carbonate, methyl ethyl carbonate, dimethoxyethane, acetonitrile, propionitrile, tetrahydrofuran, 2-methyltetrahydrofuran, dioxane, nitromethane, N, N-dimethylformamide, dimethylsulfoxide. , Sulfolane,
And γ-butyrolactone.

However, in the case where two or more kinds of mixed solvents are used, in the case where the electrolyte in which A ^{q + in} the general formula (1) is Li ion, an aprotic solvent having a dielectric constant of 20 or more among these non-aqueous solvents is used. It is preferable to prepare an electrolytic solution by dissolving the same in a mixed solvent comprising an aprotic solvent having a dielectric constant of 10 or less. In particular, lithium salts have low solubility in aprotic solvents having a dielectric constant of 10 or less, such as diethyl ether and dimethyl carbonate, and do not provide sufficient ionic conductivity by themselves, and conversely, aprotic solvents having a dielectric constant of 20 or more. When used alone, the solubility is high but the viscosity is high, so that ions are difficult to move, and sufficient ion conductivity cannot be obtained. If these are mixed, appropriate solubility and mobility can be secured, and sufficient ionic conductivity can be obtained.

The polymer for dissolving the electrolyte is not particularly limited as long as it is an aprotic polymer. For example, a polymer having polyethylene oxide in a main chain or a side chain, a homopolymer or copolymer of polyvinylidene fluoride, a methacrylate polymer, a polyacrylonitrile, and the like can be given. When adding a plasticizer to these polymers, the above-mentioned aprotic non-aqueous solvents can be used. The mixed electrolyte concentration of the present invention in these ionic conductors is 0.1 mol /
dm ³ or more and saturated concentration or less, preferably 0.5 mol
/ Dm ³ or more and 1.5 mol / dm ³ or less. 0.1
If the concentration is lower than mol / dm ³ , the ion conductivity is low, which is not preferable.

The material for the negative electrode is not particularly limited.
In the case of a lithium battery, lithium metal or an alloy of lithium and another metal is used. In the case of a lithium ion battery, a material utilizing a phenomenon called intercalation, such as carbon, natural graphite, or a metal oxide obtained by firing a polymer, an organic substance, pitch, or the like, is used. In the case of an electric double layer capacitor, activated carbon, porous metal oxide, porous metal, conductive polymer and the like are used.

The material of the positive electrode is not particularly limited.
For lithium batteries and lithium ion batteries, for example,
LiCoO_Two , LiNiO_Two , LiMnO_Two , LiMn
_Two O _Four Lithium-containing oxides such as TiO_Two , V_Two O_Five ,
MoO_Three Oxides such as TiS _Two , Sulfides such as FeS,
Or polyacetylene, polyparaphenylene, polyani
Conductive polymers such as phosphorus and polypyrrole are used
You. Activated carbon, porous metal for electric double layer capacitors
An oxide, a porous metal, a conductive polymer, or the like is used.

[0043]

The present invention will be described below in more detail with reference to examples, but the present invention is not limited to these examples.

Example 1 In a mixed solvent of 50 vol% of propylene carbonate and 50 vol% of dimethyl carbonate,

[0045]

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Lithium borate derivative having the structure
05 mol / l and LiN (SO_TwoC_TwoF _Five)_Two0.95mo
1 / l was prepared and an electrolytic solution was prepared.
The aluminum current collector was subjected to a corrosion test. Test cell
Is aluminum as the working electrode, as the counter and reference electrode
A beaker type having lithium metal was used. Action
5 V (Li / Li⁺), No current
Did not flow. After the test, observe the working electrode surface with SEM
However, no change was observed compared to before the test.

Further, LiCoO _{2 was} prepared by using this electrolytic solution.
Was used as a positive electrode material to prepare a half cell, and a charge / discharge test of the battery was actually performed. The test cell was prepared as follows. To 90 parts by weight of LiCoO ₂ powder, 5 parts by weight of polyvinylidene fluoride (PVDF) as a binder and 5 parts by weight of acetylene black as a conductive material were mixed, and N, N-dimethylformamide was further added to form a paste. This paste was applied on an aluminum foil and dried to obtain a positive electrode for testing. Lithium metal was used for the negative electrode. Then, a cell was assembled by using a glass fiber filter as a separator and soaking the electrolytic solution in the separator.

Next, a constant current charge / discharge test was performed under the following conditions. 0.35 mA current density for both charging and discharging
/ Cm ² , charging is 4.2V, discharging is 3.0V
(Vs. Li ^/ Li ⁺ ). As a result, the initial discharge capacity was 118 mAh / g (capacity of the positive electrode). The charge / discharge was repeated 100 times, and the capacity at the 100th time was 93% of the initial capacity.

Example 2 In a mixed solvent of 50% by volume of ethylene carbonate and 50% by volume of diethyl carbonate,

[0050]

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Lithium borate derivative having the structure
10 mol / l and LiN (SO ₂ CF ₃ ) ₂ 0.90mo
1 / l was prepared, and a corrosion test of the aluminum current collector was carried out using this electrolyte in the same manner as in Example 1. When the working electrode was kept at 5 V (Li / Li ⁺ ), no current flowed. After the test, the working electrode surface was observed by SEM, but no change was observed as compared to before the test.

Further, LiCoO _{2 was} prepared by using this electrolytic solution.
To produce a cell using the positive electrode material and natural graphite as the negative electrode material.
A battery charge / discharge test was actually performed. The test cell was prepared as follows.

To 90 parts by weight of LiCoO ₂ powder, 5 parts by weight of polyvinylidene fluoride (PVD) were used as a binder.
F), 5 parts by weight of acetylene black was mixed as a conductive material, and N, N-dimethylformamide was further added to form a paste. This paste was applied on an aluminum foil and dried to obtain a positive electrode for testing.
Also, 90 parts by weight of natural graphite powder were added
0 parts by weight of polyvinylidene fluoride (PVDF) was mixed, and N, N-dimethylformamide was further added to form a slurry. This slurry is applied on a copper foil and
By drying at 50 ° C. for 12 hours, a test negative electrode body was obtained. Then, the cell was assembled by infiltrating the electrolytic solution into a polyethylene separator.

Next, a constant current charge / discharge test was performed under the following conditions. 0.35 mA current density for both charging and discharging
/ Cm ² , charging is 4.2V, discharging is 3.0V
Until I went. As a result, the charge and discharge were repeated 500 times, but the capacity at the 500th time was 91% of the initial capacity.

Example 3 In a mixed solvent of 50% by volume of ethylene carbonate and 50% by volume of dimethyl carbonate,

[0056]

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Lithium borate derivative having the structure
70 mol / l and LiN (SO ₂ CF ₃ ) (SO ₂ C
₄ F ₉₎ were prepared 0.30 mol / l and the electrolyte solution prepared by dissolving, in the same manner as in Example 1 was carried out a corrosion test of an aluminum collector by using this electrolytic solution. The working electrode is 5 V (Li /
(Li ⁺ ), no current flowed.
After the test, the working electrode surface was observed by SEM, but no change was observed as compared to before the test.

Further, a half cell using LiCoO ₂ as a cathode material was prepared in the same manner as in Example 1 using this electrolytic solution, and a constant current charge / discharge test was performed under the following conditions.
Both charging and discharging were performed at a current density of 0.35 mA / cm ² , charging was performed at 4.2 V, and discharging was performed at 3.0 V (vs. Li).
/ Li ⁺ ). As a result, the initial discharge capacity is
It was 120 mAh / g (capacity of the positive electrode). Also, 10
The charge / discharge was repeated 0 times, but the capacity at the 100th time was 8
A result of 7% was obtained.

Example 4 A solution was prepared by adding acetonitrile to 70 parts by weight of polyethylene oxide having an average molecular weight of 10,000, and 5 parts by weight of a lithium borate derivative having the same structure as in Example 1 was added to this solution. ₂ CF ₃ ) (SO ₂ C ₄ F ₉ ) was added in an amount of 25 parts by weight, cast on glass, and dried to remove acetonitrile as a solvent, thereby producing a solid polymer electrolyte membrane.

Next, a corrosion test of the aluminum current collector was performed using the solid polymer electrolyte membrane. This film was sandwiched between an aluminum electrode and a lithium electrode of a working electrode, pressed and measured. When the working electrode was kept at 5 V (Li / Li ⁺ ), no current flowed. After the test, the working electrode surface was observed by SEM, but no change was observed as compared to before the test.

Next, using this polymer solid electrolyte membrane as a substitute for the electrolyte and the separator,
A half cell using CoO ₂ as a positive electrode material was prepared,
A constant current charge / discharge test was performed under the following conditions. Both charging and discharging were performed at a current density of 0.1 mA / cm ² , charging was performed at 4.2 V, and discharging was performed at 3.0 V (vs. Li / Li).
⁺ ). As a result, the initial discharge capacity is 120
mAh / g (capacity of the positive electrode). The charge / discharge was repeated 100 times, and the capacity at the 100th time was 87% of the initial capacity.

Comparative Example 1 LiN (SO ₂ C ₂ F) was mixed in a mixed solvent of 50% by volume of ethylene carbonate and 50% by volume of dimethyl carbonate.
₅ ) An electrolytic solution in which ₂ was dissolved at 1.0 mol / l was prepared, and a corrosion test of an aluminum current collector was performed using this electrolytic solution in the same manner as in Example 1. Working electrode is 5V (Li / Li ⁺ )
, A corrosion current was observed. Further, when the working electrode surface was observed by SEM after the test, a number of pits which were considered to be caused by corrosion were observed on the surface.

Next, a half cell using LiCoO ₂ as a positive electrode material was prepared in the same manner as in Example 1 using this electrolytic solution.
A constant current charge / discharge test was performed under the following conditions. Both charging and discharging are performed at a current density of 0.35 mA / cm ² ,
The charge is 4.2 V and the discharge is 3.0 V (vs. Li / L
i ⁺ ). As a result, the initial discharge capacity is 11
It was 7 mAh / g (capacity of the positive electrode). The charge / discharge was repeated 100 times, but the 100th capacity was 69% of the initial capacity.
The result was obtained.

Comparative Example 2 In a mixed solvent of 50 vol% of propylene carbonate and 50 vol% of diethyl carbonate, LiN (SO ₂ C
An electrolytic solution in which F ₃ ) ₂ was dissolved at 1.0 mol / l was prepared, and a corrosion test of the aluminum current collector was performed using this electrolytic solution in the same manner as in Example 1. The working electrode is 5 V (Li / L
When kept at i ⁺ ), a corrosion current was observed. Further, when the working electrode surface was observed by SEM after the test, a number of pits which were considered to be caused by corrosion were observed on the surface.

Next, a half cell using LiCoO ₂ as a cathode material was prepared in the same manner as in Example 1 using this electrolytic solution.
A constant current charge / discharge test was performed under the following conditions. Both charging and discharging are performed at a current density of 0.35 mA / cm ² ,
The charge is 4.2 V and the discharge is 3.0 V (vs. Li / L
i ⁺ ). As a result, the initial discharge capacity is 11
It was 2 mAh / g (capacity of the positive electrode). The charge / discharge was repeated 100 times, but the 100th capacity was 61% of the initial capacity.
The result was obtained.

Comparative Example 3 LiN (SO ₂ C) was mixed in a mixed solvent of 50% by volume of ethylene carbonate and 50% by volume of dimethyl carbonate.
An electrolytic solution in which F ₃ ) (SO ₂ C ₄ F ₉ ) was dissolved at 1.0 mol / l was prepared, and a corrosion test of the aluminum current collector was performed using this electrolytic solution as in Example 1. Working electrode 5V
(Li / Li ⁺ ), corrosion current was observed. Further, when the working electrode surface was observed by SEM after the test, a number of pits which were considered to be caused by corrosion were observed on the surface.

Next, a half cell using LiCoO ₂ as a cathode material was prepared in the same manner as in Example 1 using this electrolytic solution.
A constant current charge / discharge test was performed under the following conditions. Both charging and discharging are performed at a current density of 0.35 mA / cm ² ,
The charge is 4.2 V and the discharge is 3.0 V (vs. Li / L
i ⁺ ). As a result, the initial discharge capacity is 11
It was 8 mAh / g (capacity of the positive electrode). The charge / discharge was repeated 100 times, but the 100th capacity was 72% of the initial capacity.
The result was obtained.

[0068]

The present invention is an electrolyte having superior cycle characteristics and storage characteristics as compared with conventional electrolytes used for electrochemical devices such as lithium batteries, lithium ion batteries, and electric double layer capacitors. An electrolyte or a solid electrolyte and a battery using the same are made possible.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C07F 5/06 C07F 5/06 Z H01G 9/038 H01M 6/16 A 9/025 6/18 E H01M 6 / 16 H01G 9/00 301D 6/18 301G (72) Inventor Mikihiro Takahashi 2805 Imafukunakadai, Kawagoe City, Saitama Prefecture Inside the Chemical Research Laboratory, Central Glass Co., Ltd. Address Central Glass Co., Ltd. Chemical Research Laboratory (72) Inventor Makoto Koide 2805 Imafukunakadai, Kawagoe-shi, Saitama F-term in Chemical Laboratory Co., Ltd. F-term (reference) 4H006 AA03 AB78 4H048 AA03 AB78 VA11 VA77 VA80 VB10 5H024 AA00 AA02 AA07 AA09 AA12 FF14 FF18 FF19 FF20 FF21 FF38 FF40 GG00 HH00 5H029 AJ04 AJ05 AK02 AK03 AK05 AK16 AL02 AL06 AL07 AL12 AM02 AM03 A M04 AM05 AM06 AM16 EJ12 EJ14 HJ20

Claims (9)

[Claims] 1. A compound comprising a chemical structural formula represented by the general formula (1) and a compound comprising a chemical structural formula represented by the general formula (2), (3) or (4) An electrolyte for an electrochemical device comprising at least one. Embedded image A ^{q +} is a metal ion, a hydrogen ion, or an onium ion, M is a transition metal, group III, group IV, or
Group V elements, a is 0 to 8, b is 0 to 8, n is 1 to
3, q represents 1 to 3 and p represents n / q, respectively.
Is halogen, C ₁ -C ₁₀ alkyl, C ₁ -C ₁₀ halogenated alkyl, C ₄ -C ₂₀ aryl, C ₄ -C ₂₀ halogenated aryl, or Z ³ R ⁶ (these alkyls,
The alkyl halide, aryl and aryl halide may have a substituent and a hetero atom in the structure. ), Z ¹ is, O, S, NR ⁴ or NR ⁴ R ^5, Z ^2,
Is O, S, NR ⁴ , or NR ⁴ R ⁵ , Z ³ is O,
S, NR ⁴ or ^{NR 4 R 5, Z 1,} Z 2, Z 3, are, each independently, R ¹ is alkylene of C ₁ ~C _30, C ₁ ~C
₃₀ alkylene halides, C ₄ -C ₂₀ arylene,
Or C ₄ -C ₂₀ halogenated arylene (the alkylene, halogenated alkylene, arylene and halogenated arylene may have a substituent or a hetero atom in the structure thereof), R ² and R ³ are Each independently,
H, halogen, alkyl of C ₁ -C ₁₀ or C ₁ -C _10,
(These alkyls and alkyl halides may have a substituent or a hetero atom in the structure thereof), R ⁴ and R ⁵ are each independently H, C ₁
Aryl -C alkyl ₁₀ or C ₄ ~C _20,, R
⁶ is alkyl of C ₁ ~C _10, C ₁ ~C ₁₀ alkyl halide, C ₄ -C ₂₀ aryl, C ₄ -C ₂₀ halogenated aryl (the alkyl, halogenated alkyl, aryl and halogen Aryl halide may have a substituent and a hetero atom in its structure.)
x, y, and z each independently represent 1 to 8. 2. M is Al, B, V, Ti, Si, Z
r, Ge, Sn, Cu, Y, Zn, Ga, Nb, Ta,
2. The electrolyte for an electrochemical device according to claim 1, wherein the electrolyte is any of Bi, P, As, Sc, Hf, and Sb. 3. The electrolyte for an electrochemical device according to claim 1, wherein A ^{q +} is one of a Li ion and a quaternary ammonium ion. 4. An electrolytic solution for an electrochemical device, comprising an electrolyte according to claim 1 dissolved in a non-aqueous solvent. 5. The electrochemical device according to claim 4, wherein the non-aqueous solvent is a mixed solvent comprising an aprotic solvent having a dielectric constant of 20 or more and an aprotic solvent having a dielectric constant of 10 or less. Electrolyte. 6. The electrolytic solution for an electrochemical device according to claim 4, wherein A ^{q + of the} electrolyte is a Li ion. 7. A solid electrolyte for an electrochemical device, comprising the electrolyte according to claim 1 dissolved in a polymer. 8. The solid electrolyte for an electrochemical device according to claim 7, wherein A ^{q + of the} electrolyte is a Li ion. 9. A battery comprising at least a positive electrode, a negative electrode, an electrolytic solution or a solid electrolyte, wherein the electrolytic solution or the solid electrolyte contains the electrolyte according to claim 1.