JP2003142157A - Electrolyte and battery using it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrolyte capable of establishing an excellent chemical stability and thermochemical stability, and a lithium secondary battery using the electrolyte. SOLUTION: The electrolyte of the lithium secondary battery contains a siloxane derivative expressed by Formula (1) and electrolyte salts. Siloxane derivative has a high chemical stability and is fire retardant or with a low vapor pressure, so that it excels also in terms of thermochemistry. Formula (1) where a is integer 1-50, m, n, q, r are integers 0-40, R1 and R2 are H atoms, alkyl radicals or radicals such that at least part of the H atoms contained in an alkyl radical are substituted with halogen atoms.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an electrolyte containing an electrolyte salt and a solvent, and a battery using the same.

[0002]

2. Description of the Related Art In recent years, portable electronic products such as a camera-integrated video tape recorder, a mobile phone or a laptop computer have been rapidly spread. Also,
From the viewpoint of environmental problems, the development of electric vehicles that do not emit exhaust gas such as NO _x into the air has come to be taken up as a social issue. Under these circumstances, batteries as portable power source and clean energy source,
In particular, research and development of secondary batteries are being actively pursued. Among them, the secondary battery (lithium secondary battery) using lithium (Li) or lithium ion (Li ⁺ ) is
Since high energy density can be obtained as compared with a lead (Pb) secondary battery or a nickel-cadmium (Ni-Cd) secondary battery, which are conventional water-based electrolyte secondary batteries, high expectations are gathered.

As the electrolyte of this lithium secondary battery,
A low-molecular-weight ethylene carbonate or propylene carbonate or a non-aqueous solvent such as a carbonic acid ester such as diethyl carbonate in which a lithium-based electrolyte salt such as LiPF ₆ is dissolved as an electrolyte salt has a relatively high conductivity,
It is widely used because it is stable in terms of electric potential.

However, although a lithium secondary battery using such an electrolyte has high performance, it may cause a problem in safety because it uses a flammable organic solvent. For example, when a current is short-circuited, a large current suddenly flows into the battery to generate heat, which causes the electrolyte containing the organic solvent to vaporize or decompose, which causes gas generation, resulting in damage, rupture, or ignition of the battery. There was a possibility.
Therefore, in order to prevent these problems, conventionally, safety measures have been taken by providing a safety valve or a current cutoff device that opens when the pressure in the battery rises.

[0005]

However, in the past, the safety was ensured by improving the structural mechanism such as a safety valve, so that the structure becomes complicated, and the structure of the battery is reduced by that amount. There was a problem that the size became large. Therefore, it is desired to fundamentally improve the battery material.

The present invention has been made in view of the above problems, and a first object thereof is to provide an electrolyte excellent in chemical stability and thermochemical stability.

A second object of the present invention is to provide a battery having excellent battery performance, which prevents the battery from being damaged or ignited by the generation of gas by suppressing vaporization or decomposition of the electrolyte. is there.

[0008]

The first electrolyte according to the present invention contains a siloxane derivative represented by the following chemical formula 5 and an electrolyte salt.

[Chemical 5] (In the formula, a represents an integer of 1 to 50, m, n, q, and r each represent an integer of 0 to 40, and R1 and R
2 represents a hydrogen atom, an alkyl group, or a group in which at least a part of hydrogen atoms contained in the alkyl group is substituted with a halogen atom. )

The second electrolyte according to the present invention has the following chemical formula:
It contains a siloxane derivative represented by and an electrolyte salt.

[Chemical 6] (In the formula, b represents an integer of 0 to 3, c represents an integer of 1 to 4, b + c is always 4, and s and t each represent an integer of 0 to 40. R3 is a methyl group. , R
4 represents a hydrogen atom, an alkyl group, or a group in which at least a part of hydrogen atoms contained in the alkyl group is substituted with a halogen atom. )

The first battery according to the present invention comprises an electrolyte together with a positive electrode and a negative electrode, and the electrolyte contains a siloxane derivative represented by the following chemical formula 7 and an electrolyte salt.

[Chemical 7] (In the formula, a represents an integer of 1 to 50, m, n, q, and r each represent an integer of 0 to 40, and R1 and R
2 represents a hydrogen atom, an alkyl group, or a group in which at least a part of hydrogen atoms contained in the alkyl group is substituted with a halogen atom. )

The second battery according to the present invention comprises a positive electrode and a negative electrode and an electrolyte, and the electrolyte contains a siloxane derivative and an electrolyte salt represented by the following chemical formula (8).

[Chemical 8] (In the formula, b represents an integer of 0 to 3, c represents an integer of 1 to 4, b + c is always 4, and s and t each represent an integer of 0 to 40. R3 is a methyl group. , R
4 represents a hydrogen atom, an alkyl group, or a group in which at least a part of hydrogen atoms contained in the alkyl group is substituted with a halogen atom. )

Since the first or second electrolyte according to the present invention contains the siloxane derivative shown in Chemical formula 5 or Chemical formula 6, it has high chemical stability, flame retardancy, and low vapor pressure. Excellent chemical properties can be obtained.

In the first or second battery according to the present invention,
Since the electrolyte contains the siloxane derivative shown in Chemical formula 7 or Chemical formula 8, vaporization or decomposition does not easily occur even when the current is short-circuited, damage or ignition of the battery is prevented, and excellent battery performance is exhibited even at high voltage. Be done.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

The electrolyte according to one embodiment of the present invention contains a solvent and an electrolyte salt. The solvent dissolves and dissociates the electrolyte salt. The solvent contains at least one of the siloxane derivatives shown in Chemical formula 9 or Chemical formula 10.

[0016]

[Chemical 9] (In the formula, a represents an integer of 1 to 50, m, n, q, and r each represent an integer of 0 to 40, and R1 and R
2 represents a hydrogen atom, an alkyl group, or a group in which at least a part of hydrogen atoms contained in the alkyl group is substituted with a halogen atom. Note that m, n, q, and r may have the same value or different values, and R1 and R2 may be the same or different. )

[0017]

[Chemical 10] (In the formula, b represents an integer of 0 to 3, c represents an integer of 1 to 4, b + c is always 4, and s and t each represent an integer of 0 to 40. R3 is a methyl group. , R
4 represents a hydrogen atom, an alkyl group, or a group in which at least a part of hydrogen atoms contained in the alkyl group is substituted with a halogen atom. Note that s and t may have the same value or different values. )

These siloxane derivatives are silicon (S
It is a chain-type inorganic polymer having a chain bond of i) and oxygen (O) as a basic skeleton, and a side chain which is a monovalent organic group is added to silicon. These siloxane derivatives have characteristics of high chemical stability, flame retardancy, and low vapor pressure and therefore excellent thermochemical stability.

The kinematic viscosity of these siloxane derivatives at a temperature of 25 ° C. is 5000 mm ² / s (5000 cSt).
The following is preferable, and the weight average molecular weight is 1000.
It is preferably 0 or less. This is because it is necessary to have a relatively low viscosity and to be able to dissolve the electrolyte salt in order to use it as a solvent for the electrolyte. The kinematic viscosity and the weight average molecular weight can be determined, for example, by selecting the values of a, m, n, q and r shown in Chemical formula 9, or b shown in Chemical formula 10,
Prepared by choosing values for c, s and t.
For example, in the case of the siloxane derivative shown in Chemical formula 9, a is preferably an integer in the range of 1 to 20.

Examples of electrolyte salts include light metal salts.
You can Lithium salt and sodium (N
a) Alkali metal such as salt or potassium (K) salt
Salt, magnesium (Mg) salt or calcium
Alkaline earth metal salt such as (Ca) salt, or aluminum
There are um (Al) salts, etc.
Several types are selected. For example, if it is a lithium salt, Li
BF_Four, LiClO_Four, LiPF₆, LiAsF₆, C
F₃SO₃Li, (CF₃SO₂)₂NLi, C _FourF₉
SO₃Li, CF₃CO₂Li, (CF₃CO₂)₂N
Li, C₆F_FiveSO₃Li, C₈F₁₇SO₃Li, (C
₂F_FiveSO₂)₂NLi, (C_FourF₉SO ₂) (CF₃
SO₂) NLi, (FSO₂C₆F_Four) (CF₃S
O₂) NLi, ((CF₃)₂CHOSO₂)₂NL
i, (CF₃SO₂)₃CLi, (C₆F ₃(CF₃)
₂-3, 5)_FourBLi, LiCF₃Or LiAlC
l_FourAnd any one or two of these
A mixture of two or more species is used.

The conductivity of this electrolyte at a temperature of 25 ° C. is preferably 0.01 S / m or more, and is adjusted depending on the type of electrolyte salt or its concentration.

The electrolyte may contain other solvent in addition to the siloxane derivative described above. Examples of other solvents include propylene carbonate, ethylene carbonate, diethyl carbonate, methyl ethyl carbonate, 1,2-dimethoxyethane, 1,2-diethoxyethane, γ-butyrolactone, tetrahydrofuran, 1,3-dioxolane, dipropyl. Carbonate,
Diethyl ether, sulfolane, methyl sulfolane, acetonitrile, propionitrile, anisole, acetic acid ester or propionic acid ester, and the like,
Any one of these or a mixture of two or more thereof is used.

The electrolyte having such a structure is used in a battery as follows. Here, an example of a lithium secondary battery will be given and described below with reference to the drawings.

FIG. 1 shows a sectional structure of a secondary battery using the electrolyte according to this embodiment. This secondary battery is of a so-called coin type, in which a disk-shaped negative electrode 12 housed in an outer cup 11 and a disk-shaped positive electrode 14 housed in an outer can 13 are separated by a separator 15. Are stacked. The insides of the outer cup 11 and the outer can 13 are filled with the electrolyte 16 according to the present embodiment, and the peripheral portions of the outer cup 11 and the outer can 13 are caulked via an insulating gasket 17 to be hermetically sealed. There is.

The negative electrode 12 contains, for example, a negative electrode material capable of inserting and extracting lithium ions or lithium metal as a negative electrode active material, and further contains a binder such as polyvinylidene fluoride, if necessary.

Examples of the negative electrode material capable of inserting and extracting lithium ions include carbon materials, metal oxides and polymer materials. As a carbon material,
For example, pyrolytic carbons, cokes such as petroleum coke or pitch coke, artificial graphites, natural graphites, carbon black such as acetylene black, glassy carbons, organic polymer material fired bodies or carbon fibers Examples include those prepared at temperature and atmosphere. The term "calcined organic polymer material" means that the organic polymer material is heated in an inert gas atmosphere or in a vacuum.
It was baked at an appropriate temperature of 0 ° C. or higher. Examples of metal oxides include iron oxide, ruthenium oxide, molybdenum oxide, and the like, and examples of polymer materials include polyacetylene, polypyrrole, and the like.

As the negative electrode material capable of inserting and extracting lithium, a simple substance, an alloy or a compound of a metal element or a metalloid element capable of forming an alloy with lithium can also be mentioned. In the present specification, the alloy includes not only an alloy composed of two or more kinds of metal elements but also an alloy composed of one or more kinds of metal elements and one or more kinds of metalloid elements.
The texture may be a solid solution, a eutectic (eutectic mixture), an intermetallic compound, or a coexistence of two or more of them.

Examples of such metal elements or metalloid elements are tin (Sn), lead (Pb), aluminum, indium (In), silicon, zinc (Zn), copper (Cu), cobalt (Co). , Antimony (Sb), bismuth (Bi), cadmium (Cd), magnesium,
Boron (B), Gallium (Ga), Germanium (G
e), arsenic (As), silver (Ag), hafnium (H
f), zirconium (Zr) and yttrium (Y)
Is mentioned. As these alloys or compounds,
For example, the formula Ma _d Mb _e Li _f or formula M,
Examples thereof include those represented by a _g Mc _h Md _i . In these chemical formulas, Ma represents at least one of a metal element and a metalloid element capable of forming an alloy with lithium, Mb represents at least one of a metal element other than lithium and Ma, and a metalloid element, Mc represents at least one kind of non-metal element, and Md represents at least one kind of metal element and metalloid element other than Ma. The values of d, e, f, g, h and i are d>
0, e ≧ 0, f ≧ 0, g> 0, h> 0, i ≧ 0.

Among these, simple substances, alloys or compounds of 4B group metal elements or metalloid elements are preferable, and particularly preferable are silicon or tin, or alloys or compounds thereof. These may be crystalline or amorphous.

About such alloys or compounds
Physically, for example, LiAl, AlSb, CuMgS
b, SiB_Four, SiB₆, Mg₂Si, Mg₂Sn, N
i₂Si, TiSi₂, MoSi₂, CoSi₂, Ni
Si₂, CaSi₂, CrSi₂, Cu_FiveSi, FeS
i₂, MnSi₂, NbSi₂, TaSi₂, VS
i ₂, WSi₂, ZnSi₂, SiC, Si₃N_Four, S
i₂N₂O, SiO_v(0 <v ≦ 2), SnO_w(0 <
w ≦ 2), SnSiO₃, LiSiO or LiSn
There is O etc.

As the negative electrode material capable of inserting and extracting lithium, any one kind or a mixture of two or more kinds thereof may be used.

The positive electrode 14 contains, for example, a positive electrode active material, and if necessary, further contains a conductive agent such as carbon black or graphite and a binder such as polyvinylidene fluoride.

Examples of the positive electrode active material include oxides and sulfides capable of inserting and extracting lithium ions, and any one or more of these may be used. Specifically, for example, TiS ₂ , MoS ₂
Alternatively, a metal sulfide or oxide containing no lithium such as V ₂ O ₅ or a lithium composite oxide containing lithium may be used, and NbSe ₂ may also be used. Above all, to increase the energy density, Li _x
A lithium composite oxide mainly composed of MO ₂ is preferable. In addition, M is preferably one or more kinds of transition metal elements, specifically, cobalt, nickel (Ni) and manganese (M
At least one of n) is preferred. Also, x is
Usually, it is a value within the range of 0.05 ≦ x ≦ 1.10. Specific examples of such a lithium composite oxide include LiC
oO ₂ , LiNiO ₂ , Li _x Ni _y Co _1-y O ₂ (however, the values of x and y differ depending on the charge / discharge state of the battery, and are generally 0 <x <1 and 0.7 <y ≦ 1. .) Or LiMn ₂ O _{4 and the} like.

The lithium composite oxide may be, for example, a lithium carbonate, nitrate, oxide or hydroxide and a transition metal carbonate, nitrate, oxide or hydroxide depending on the desired composition. It is prepared by pulverizing, mixing, and firing in an oxygen atmosphere at a temperature in the range of 600 ° C to 1000 ° C.

The separator 15 separates the negative electrode 12 and the positive electrode 14 and allows lithium ions to pass through while preventing a short circuit of the current due to the contact of both electrodes. For example, a composite of polytetrafluoroethylene, polypropylene or polyethylene is used. It is composed of a resin non-woven fabric, a ceramic film, a porous thin film, or the like.

The secondary battery having such a structure operates as follows.

In this secondary battery, when charged, the positive electrode 1
Lithium ions are desorbed from No. 4, pass through the separator 15 through the electrolyte 16, and are occluded in the negative electrode 12. After that, when discharged, lithium ions are desorbed from the negative electrode 12, pass through the separator 15 through the electrolyte 16, return to the positive electrode 14, and are occluded. Here, since the electrolyte 16 contains the siloxane derivative shown in Chemical formula 9 or Chemical formula 10 as a solvent, it has high chemical stability, and is also flame-retardant or has a low vapor pressure, so that it is also excellent in thermochemistry. There is. Therefore, even when the current is short-circuited, vaporization or decomposition hardly occurs, damage or ignition of the battery is prevented, and excellent battery performance is exhibited even at high voltage.

As described above, according to the electrolyte of the present embodiment, since the siloxane derivative shown in Chemical formula 9 or Chemical formula 10 is contained as the solvent, the chemical stability and thermochemical stability should be enhanced. You can Therefore, if a battery is configured using this electrolyte, vaporization or decomposition of the electrolyte can be suppressed even when a large current suddenly flows when the current is short-circuited. Therefore, it is possible to prevent damage or ignition of the battery,
It is possible to improve safety and obtain excellent battery performance even at high voltage.

Further, the kinematic viscosity of the siloxane derivative shown in Chemical formula 9 or Chemical formula 10 at a temperature of 25 ° C. is 5000 mm.
^{When the} ratio is ² / s or less or the weight average molecular weight is 10,000 or less, it is possible to dissolve the electrolyte salt sufficient to bring out high conductivity, and the ions generated by the dissociation of the electrolyte salt may move. It is possible to obtain a good electrolyte.

[0040]

EXAMPLES Further, specific examples of the present invention will be described in detail.

(Examples 1-1 to 1-3) As a solvent, a siloxane derivative represented by Chemical formula 11 having a weight average molecular weight of 631 was prepared, and a lithium salt of (CF ₃ SO 4) was prepared.
₂ ) ₂ NLi was added to prepare an electrolyte. At that time, (CF ₃ SO ₂ ) ₂ NLi was added to 1 g of the siloxane derivative.
The amount added was changed as shown in Table 1 in Examples 1-1 to 1-3. The siloxane derivative shown in Chemical formula 11 has a = 1, m = 0, n = in the chemical formula shown in Chemical formula 9.
4, q = 4, r = 0, R1 = CH ₃ and R2 = CH ₃
It is the case of. Temperature of this siloxane derivative 25
The kinematic viscosity at 0 ° C. was 16 mm ² / s.

[0042]

[Chemical 11]

[0043]

[Table 1]

An ionic conductivity test was conducted on each of the obtained electrolytes of Examples 1-1 to 1-3. In the ionic conductivity test, a voltage was applied by sandwiching the electrolyte between stainless steel plates having a thickness of 0.145 cm and an area of 0.7854 cm ² , and the applied sinusoidal AC voltage was represented by a symbolic method (complex display).
The conductivity was obtained from the so-called Cole-Cole plot expressed by. The results obtained are shown in Table 1.

Comparative examples 1-1 and 1 with respect to this example
An electrolyte was prepared in the same manner as in this example except that the siloxane derivative represented by Chemical formula 12 having a weight average molecular weight of 3310 was used as the solvent for -2. At that time, (CF ₃ SO ₂ ) ₂ per 1 g of the siloxane derivative
The addition amount of NLi was changed as shown in Table 1 in Comparative Examples 1-1 and 1-2. Regarding the electrolytes of Comparative Examples 1-1 and 1-2, the electric conductivity was obtained in the same manner as in this example. These results are also shown in Table 1. Note that Comparative Example 1-1 corresponds to Example 1-1, and Comparative Example 1-2 corresponds to Example 1-2.

[0046]

[Chemical 12]

As can be seen from Table 1, according to this example, the conductivity was higher than that of Comparative examples 1-1 and 1-2, and the conductivity that could be used for the battery was obtained.

Further, using the obtained electrolyte of Example 1-2, a coin type test cell as shown in FIG. 1 was prepared and a charge / discharge test was conducted to examine the discharge characteristics. LiCoO ₂ was used for the positive electrode of the test cell, and a carbon material was used for the negative electrode. For charging and discharging, the upper limit voltage is 4.2V and the lower limit voltage is 3.0V.
The cycle was repeated up to 20 cycles with V and discharge current set to 100 μA. The charge / discharge curve obtained as a result is shown in FIG. From FIG. 2, it was found that the battery using this electrolyte has sufficient charge / discharge characteristics. Therefore, it was found that excellent battery performance can be obtained by using the electrolyte containing the siloxane derivative shown in Chemical formula 11.

(Examples 2-1 to 2-6) Examples 2-1 to 2-1
2-3, except that the siloxane derivative shown in Chemical formula 13 having a weight average molecular weight of 1014 is used as the solvent,
An electrolyte was prepared in the same manner as in Example 1-1, except for the above. At that time, (CF ₃ SO ₂ ) ₂ per 1 g of the siloxane derivative
The addition amount of NLi was changed as shown in Table 2 in Examples 2-1 to 2-3. In addition, the siloxane derivative shown in Chemical formula 13 has b = 1 and c = in the chemical formula shown in Chemical formula 10.
3, s = 4, t = if 0 and R4 = CH ₃ is of. The kinematic viscosity of this siloxane derivative at a temperature of 25 ° C. was 23 mm ² / s.

[0050]

[Chemical 13]

[0051]

[Table 2]

Further, as Examples 2-4 to 2-6, a solvent was used.
In which the weight average molecular weight is 1322.
Other than Example 1-1 except that the xane derivative was used.
An electrolyte was prepared in the same manner. At that time, siloxane induction
(CF for 1 g of body₃SO ₂)₂Add the amount of NLi added
Changes were made as shown in Table 3 in Examples 2-4 to 2-6.
The siloxane derivative shown in Chemical formula 14 is shown in Chemical formula 10
In the chemical formula, b = 0, c = 4, s = 4, t = 0
And R4 = CH₃It is the case of. This siloxane
The kinematic viscosity of the derivative at a temperature of 25 ° C is 28 mm.²/ S
It was.

[0053]

[Chemical 14]

[0054]

[Table 3]

With respect to the obtained electrolytes of Examples 2-1 to 2-6, the ionic conductivity test was conducted in the same manner as in Example 1-1, and the conductivity was determined. The obtained results are shown in Comparative Example 1-
It is shown in Table 2 or Table 3 together with the results of 1 and 1-2. In addition, Comparative Example 1-1 corresponds to Example 2-1 and Example 2-4, and Comparative Example 1-2 is Example 2-2 and Example 2-.
It corresponds to 5.

As can be seen from Tables 2 and 3, according to this example, the conductivity was higher than that of Comparative Examples 1-1 and 1-2, and the conductivity which could be used for the battery was obtained. .

Further, using the obtained electrolyte of Example 2-2, a coin type test cell as shown in FIG. 1 was prepared in the same manner as in Example 1-2, and the discharge characteristics were examined. The obtained charge / discharge curve is shown in FIG. From FIG. 3, it was found that the battery using this electrolyte has sufficient charge / discharge characteristics.
Therefore, it was found that excellent battery performance can be obtained by using the electrolyte containing the siloxane derivative shown in Chemical formula 13.

In the above Examples, the siloxane derivative shown in Chemical formula 9 is the siloxane derivative shown in Chemical formula 11, and the siloxane derivative shown in Chemical formula 10 is the siloxane derivative shown in Chemical formula 13 and Chemical formula 14 below. However, similar results can be obtained with the general siloxane derivatives represented by the above chemical formulas 9 and 10 other than those shown in the chemical formulas 11, 13, and 14.

Although the present invention has been described with reference to the embodiments and examples, the present invention is not limited to the above-described embodiments and examples, and various modifications can be made. For example, in the above embodiments and examples, the secondary battery in which the electrode reactive species is lithium has been described. However, in the present invention, the electrode reactive species is another alkali metal such as sodium or potassium, or magnesium or calcium. The same can be applied to a battery made of Alkaline earth metal or other light metal such as aluminum. In that case, the electrolyte salt is appropriately selected accordingly.

Although the coin type secondary battery has been described in the above-mentioned embodiments and examples, the present invention has other shapes such as a button type, a paper type, a square type and a cylindrical type having a spiral structure. The same can be applied to the thing.

Further, although the secondary battery is described in the above-mentioned embodiments and examples, the present invention can be applied to other batteries such as a primary battery.

[0062]

As described above, since the electrolyte according to any one of claims 1 to 10 contains the siloxane derivative shown in Chemical formula 1 or Chemical formula 2, chemical stability and chemical stability are improved. An effect that thermochemical stability can be enhanced is exhibited.

Particularly, according to the electrolyte of claim 2, claim 3, claim 7 or claim 8, the siloxane derivative has a kinematic viscosity at a temperature of 25 ° C. of not more than 5000 mm ² / s or a weight average molecular weight of 10,000. Since it is set as follows, it is possible to dissolve the electrolyte salt enough to bring out the high conductivity, and it is possible to satisfactorily move the ions generated by the dissociation.

Further, according to the battery of any one of claims 11 to 20, since the battery containing the siloxane derivative shown in Chemical formula 3 or Chemical formula 4 is provided, the battery rapidly increases when the current is short-circuited. Even if an electric current flows, vaporization or decomposition of the electrolyte can be suppressed. Therefore, it is possible to prevent damage or ignition of the battery, improve safety, and obtain excellent battery performance even at high voltage.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a configuration of a secondary battery using an electrolyte according to an embodiment of the present invention.

FIG. 2 is a characteristic diagram showing a charge / discharge curve in a discharge characteristic test of an electrolyte according to Example 1-2 of the invention.

FIG. 3 is a characteristic diagram showing a charge / discharge curve in a discharge characteristic test of an electrolyte according to Example 2-2 of the present invention.

[Explanation of symbols]

11 ... Exterior cup, 12 ... Negative electrode, 13 ... Exterior can, 14 ...
Positive electrode, 15 ... Separator, 16 ... Electrolyte, 17 ... Gasket

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 4J002 CP181 DE186 DG036 DH046                       FD206 GQ00 HA08                 5G301 CA30 CD01                 5H029 AJ07 AJ12 AK02 AK03 AK05                       AL02 AL03 AL06 AL07 AL08                       AL11 AL12 AL16 AL18 AM02                       AM03 AM04 AM05 AM07 AM16                       BJ03 EJ12 EJ14 HJ02 HJ10                       HJ11 HJ20

Claims (20)

[Claims] 1. An electrolyte comprising a siloxane derivative represented by the following chemical formula 1 and an electrolyte salt. [Chemical 1] (In the formula, a represents an integer of 1 to 50, m, n, q, and r each represent an integer of 0 to 40, and R1 and R
2 represents a hydrogen atom, an alkyl group, or a group in which at least a part of hydrogen atoms contained in the alkyl group is substituted with a halogen atom. ) 2. The electrolyte according to claim 1, wherein the siloxane derivative has a kinematic viscosity at a temperature of 25 ° C. of 5000 mm ² / s or less. 3. The electrolyte according to claim 1, wherein the siloxane derivative has a weight average molecular weight of 10,000 or less. 4. The electrolyte according to claim 1, wherein the electrolyte salt is a lithium salt. 5. An electric conductivity of 0.01 S at a temperature of 25 ° C.
/ M or more, The electrolyte of Claim 1 characterized by the above-mentioned. 6. An electrolyte comprising a siloxane derivative represented by the following chemical formula 2 and an electrolyte salt. [Chemical 2] (In the formula, b represents an integer of 0 to 3, c represents an integer of 1 to 4, b + c is always 4, and s and t each represent an integer of 0 to 40. R3 is a methyl group. , R
4 represents a hydrogen atom, an alkyl group, or a group in which at least a part of hydrogen atoms contained in the alkyl group is substituted with a halogen atom. ) 7. The electrolyte according to claim 6, wherein the siloxane derivative has a kinematic viscosity at a temperature of 25 ° C. of 5000 mm ² / s or less. 8. The electrolyte according to claim 6, wherein the siloxane derivative has a weight average molecular weight of 10,000 or less. 9. The electrolyte according to claim 6, wherein the electrolyte salt is a lithium salt. 10. The electrical conductivity at a temperature of 25 ° C. is 0.01.
The electrolyte according to claim 6, which has an S / m or more. 11. A battery provided with an electrolyte together with a positive electrode and a negative electrode, wherein the electrolyte contains a siloxane derivative and an electrolyte salt shown in Chemical formula 3 below. [Chemical 3] (In the formula, a represents an integer of 1 to 50, m, n, q, and r each represent an integer of 0 to 40, and R1 and R
2 represents a hydrogen atom, an alkyl group, or a group in which at least a part of hydrogen atoms contained in the alkyl group is substituted with a halogen atom. ) 12. The battery according to claim 11, wherein the electrolyte contains a siloxane derivative having a kinematic viscosity at a temperature of 25 ° C. of 5000 mm ² / s or less. 13. The electrolyte has a weight average molecular weight of 10
12. The battery according to claim 11, comprising 000 or less siloxane derivative. 14. The battery according to claim 11, wherein the electrolyte has a conductivity of 0.01 S / m or more at a temperature of 25 ° C. 15. The positive electrode contains an oxide or a sulfide capable of absorbing and desorbing lithium ions, and the negative electrode comprises a negative electrode material capable of absorbing and desorbing lithium ions or a lithium metal. The battery according to claim 11, comprising: 16. A battery provided with an electrolyte together with a positive electrode and a negative electrode, wherein the electrolyte contains a siloxane derivative and an electrolyte salt shown in Chemical formula 4 below. [Chemical 4] (In the formula, b represents an integer of 0 to 3, c represents an integer of 1 to 4, b + c is always 4, s and t each represent an integer of 0 to 40, and R3 is a methyl group. , R
4 represents a hydrogen atom, an alkyl group, or a group in which at least a part of hydrogen atoms contained in the alkyl group is substituted with a halogen atom. ) 17. The battery according to claim 16, wherein the electrolyte contains a siloxane derivative having a kinematic viscosity at a temperature of 25 ° C. of 5000 mm ² / s or less. 18. The electrolyte has a weight average molecular weight of 10
17. The battery according to claim 16, comprising 000 or less siloxane derivative. 19. The battery according to claim 16, wherein the electrolyte has a conductivity of 0.01 S / m or more at a temperature of 25 ° C. 20. The positive electrode contains an oxide or a sulfide capable of absorbing and desorbing lithium ions, and the negative electrode comprises a negative electrode material capable of absorbing and desorbing lithium ions or a lithium metal. The battery according to claim 16, comprising: