WO2018220795A1 - Electrolytic solution and electrochemical device - Google Patents

Electrolytic solution and electrochemical device Download PDF

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Publication number
WO2018220795A1
WO2018220795A1 PCT/JP2017/020472 JP2017020472W WO2018220795A1 WO 2018220795 A1 WO2018220795 A1 WO 2018220795A1 JP 2017020472 W JP2017020472 W JP 2017020472W WO 2018220795 A1 WO2018220795 A1 WO 2018220795A1
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Prior art keywords
negative electrode
mass
formula
group
electrochemical device
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PCT/JP2017/020472
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French (fr)
Japanese (ja)
Inventor
馨 今野
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日立化成株式会社
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Priority to PCT/JP2017/020472 priority Critical patent/WO2018220795A1/en
Priority to CN201880035266.6A priority patent/CN110679030B/en
Priority to KR1020197036220A priority patent/KR102561972B1/en
Priority to US16/615,666 priority patent/US11398643B2/en
Priority to JP2019521983A priority patent/JP7074132B2/en
Priority to EP18810812.0A priority patent/EP3637528A4/en
Priority to PCT/JP2018/014283 priority patent/WO2018220997A1/en
Priority to JP2019521307A priority patent/JP7131553B2/en
Priority to US16/615,653 priority patent/US11411250B2/en
Priority to CN201880035267.0A priority patent/CN110710047B/en
Priority to KR1020197036221A priority patent/KR102576486B1/en
Priority to PCT/JP2018/021013 priority patent/WO2018221671A1/en
Priority to EP18810582.9A priority patent/EP3637527A4/en
Priority to TW107118900A priority patent/TWI775863B/en
Publication of WO2018220795A1 publication Critical patent/WO2018220795A1/en

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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES OR LIGHT-SENSITIVE DEVICES, OF THE ELECTROLYTIC TYPE
    • H01G11/00—Hybrid capacitors, i.e. capacitors having different positive and negative electrodes; Electric double-layer [EDL] capacitors; Processes for the manufacture thereof or of parts thereof
    • H01G11/54—Electrolytes
    • H01G11/58—Liquid electrolytes
    • H01G11/64—Liquid electrolytes characterised by additives
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/056—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes
    • H01M10/0564—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes the electrolyte being constituted of organic materials only
    • H01M10/0566—Liquid materials
    • H01M10/0567—Liquid materials characterised by the additives
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10—Energy storage using batteries

Definitions

  • the present invention relates to an electrolytic solution and an electrochemical device.
  • Patent Document 1 discloses a non-aqueous electrolyte battery electrolyte containing a specific siloxane compound in order to improve cycle characteristics and internal resistance characteristics.
  • an object of the present invention is to provide an electrolytic solution that can improve cycle characteristics of an electrochemical device. Another object of the present invention is to provide an electrochemical device having excellent cycle characteristics.
  • the present invention provides an electrolytic solution containing a compound represented by the following formula (1).
  • R 1 to R 3 each independently represents an alkyl group or a fluorine atom
  • R 4 represents an alkylene group
  • R 5 represents an organic group containing a sulfur atom.
  • R 5 is preferably a group represented by any of the following formula (2), formula (3) or formula (4).
  • R 6 represents an alkyl group, and * represents a bond.
  • R 7 represents an alkyl group, and * represents a bond.
  • R 8 represents an alkyl group, and * represents a bond.
  • At least one of R 1 to R 3 is preferably a fluorine atom.
  • the content of the compound represented by the formula (1) is preferably 10% by mass or less based on the total amount of the electrolytic solution.
  • the present invention provides, as a second aspect, an electrochemical device comprising a positive electrode, a negative electrode, and the above electrolytic solution.
  • the negative electrode preferably contains a carbon material.
  • the carbon material preferably contains graphite.
  • the negative electrode preferably further contains a material containing at least one element of the group consisting of silicon and tin.
  • the electrochemical device is preferably a non-aqueous electrolyte secondary battery or a capacitor.
  • an electrolytic solution capable of improving the cycle characteristics of an electrochemical device.
  • the electrochemical device excellent in cycling characteristics can be provided.
  • FIG. 5 is a graph showing evaluation results of cycle characteristics of Example 1 and Comparative Example 1.
  • 6 is a graph showing evaluation results of cycle characteristics of Examples 2 to 5 and Comparative Examples 2 to 3.
  • FIG. 1 is a perspective view showing an electrochemical device according to an embodiment.
  • the electrochemical device is a non-aqueous electrolyte secondary battery.
  • the nonaqueous electrolyte secondary battery 1 includes an electrode group 2 composed of a positive electrode, a negative electrode, and a separator, and a bag-shaped battery exterior body 3 that houses the electrode group 2.
  • a positive electrode current collecting tab 4 and a negative electrode current collecting tab 5 are provided on the positive electrode and the negative electrode, respectively.
  • the positive electrode current collecting tab 4 and the negative electrode current collecting tab 5 protrude from the inside of the battery outer package 3 to the outside so that the positive electrode and the negative electrode can be electrically connected to the outside of the nonaqueous electrolyte secondary battery 1, respectively. .
  • the battery outer package 3 is filled with an electrolytic solution (not shown).
  • the non-aqueous electrolyte secondary battery 1 may be a battery (coin type, cylindrical type, laminated type, etc.) having a shape other than the so-called “laminate type” as described above.
  • the battery outer package 3 may be a container formed of a laminate film, for example.
  • the laminate film may be a laminate film in which a resin film such as a polyethylene terephthalate (PET) film, a metal foil such as aluminum, copper, and stainless steel, and a sealant layer such as polypropylene are laminated in this order.
  • PET polyethylene terephthalate
  • metal foil such as aluminum, copper, and stainless steel
  • sealant layer such as polypropylene
  • FIG. 2 is an exploded perspective view showing an embodiment of the electrode group 2 in the nonaqueous electrolyte secondary battery 1 shown in FIG.
  • the electrode group 2 includes a positive electrode 6, a separator 7, and a negative electrode 8 in this order.
  • the positive electrode 6 and the negative electrode 8 are arranged so that the surfaces on the positive electrode mixture layer 10 side and the negative electrode mixture layer 12 side face the separator 7, respectively.
  • the positive electrode 6 includes a positive electrode current collector 9 and a positive electrode mixture layer 10 provided on the positive electrode current collector 9.
  • the positive electrode current collector 9 is provided with a positive electrode current collector tab 4.
  • the positive electrode current collector 9 is made of, for example, aluminum, titanium, stainless steel, nickel, baked carbon, conductive polymer, conductive glass, or the like.
  • the positive electrode current collector 9 may have a surface such as aluminum or copper that has been treated with carbon, nickel, titanium, silver, or the like for the purpose of improving adhesiveness, conductivity, and oxidation resistance.
  • the thickness of the positive electrode current collector 9 is, for example, 1 to 50 ⁇ m from the viewpoint of electrode strength and energy density.
  • the positive electrode mixture layer 10 contains a positive electrode active material, a conductive agent, and a binder.
  • the thickness of the positive electrode mixture layer 10 is, for example, 20 to 200 ⁇ m.
  • the positive electrode active material may be lithium oxide, for example.
  • the content of the positive electrode active material may be 80% by mass or more, 85% by mass or more, and 99% by mass or less based on the total amount of the positive electrode mixture layer.
  • the conductive agent may be a carbon black such as acetylene black or ketjen black, a carbon material such as graphite or graphene, or a carbon nanotube.
  • the content of the conductive agent may be, for example, 0.01% by mass or more, 0.1% by mass or more, or 1% by mass or more based on the total amount of the positive electrode mixture layer, and is 50% by mass or less, 30% by mass. Or 15% by mass or less.
  • binder examples include resins such as polyethylene, polypropylene, polyethylene terephthalate, polymethyl methacrylate, polyimide, aromatic polyamide, cellulose, and nitrocellulose; SBR (styrene-butadiene rubber), NBR (acrylonitrile-butadiene rubber), fluorine rubber Rubber such as isoprene rubber, butadiene rubber, ethylene-propylene rubber; styrene / butadiene / styrene block copolymer or hydrogenated product thereof, EPDM (ethylene / propylene / diene terpolymer), styrene / ethylene / butadiene / Thermoplastic elastomers such as ethylene copolymers, styrene / isoprene / styrene block copolymers or hydrogenated products thereof; syndiotactic-1, 2-polybutadiene, polyvinyl acetate, ethylene /
  • the content of the binder may be, for example, 0.1% by mass or more, 1% by mass or more, or 1.5% by mass or more based on the total amount of the positive electrode mixture layer, and is 30% by mass or less, 20% by mass. % Or less, or 10 mass% or less.
  • the separator 7 is particularly limited as long as it electrically insulates between the positive electrode 6 and the negative electrode 8 and allows ions to pass therethrough and has resistance to oxidation on the positive electrode 6 side and reduction on the negative electrode 8 side.
  • Examples of the material (material) of the separator 7 include resins and inorganic substances.
  • the separator 7 is preferably a porous sheet or a nonwoven fabric formed of polyolefin such as polyethylene or polypropylene from the viewpoint of being stable with respect to the electrolytic solution and having excellent liquid retention.
  • the separator 7 may be a separator in which a fibrous or particulate inorganic substance is adhered to a thin film substrate such as a nonwoven fabric, a woven fabric, or a microporous film.
  • the negative electrode 8 includes a negative electrode current collector 11 and a negative electrode mixture layer 12 provided on the negative electrode current collector 11.
  • the negative electrode current collector 11 is provided with a negative electrode current collector tab 5.
  • the negative electrode current collector 11 is made of copper, stainless steel, nickel, aluminum, titanium, baked carbon, conductive polymer, conductive glass, aluminum-cadmium alloy, or the like.
  • the negative electrode current collector 11 may be one in which the surface of copper, aluminum or the like is treated with carbon, nickel, titanium, silver or the like for the purpose of improving adhesiveness, conductivity, and reduction resistance.
  • the thickness of the negative electrode current collector 11 is, for example, 1 to 50 ⁇ m from the viewpoint of electrode strength and energy density.
  • the negative electrode mixture layer 12 contains, for example, a negative electrode active material and a binder.
  • the negative electrode active material is not particularly limited as long as it is a material capable of occluding and releasing lithium ions.
  • Examples of the negative electrode active material include carbon materials, metal composite oxides, oxides or nitrides of Group 4 elements such as tin, germanium, and silicon, lithium alone, lithium alloys such as lithium aluminum alloys, Sn, Si, and the like And metals capable of forming an alloy with lithium.
  • the negative electrode active material is preferably at least one selected from the group consisting of a carbon material and a metal composite oxide from the viewpoint of safety.
  • the negative electrode active material may be one of these alone or a mixture of two or more.
  • the shape of the negative electrode active material may be, for example, a particulate shape.
  • carbon materials examples include amorphous carbon materials, natural graphite, composite carbon materials in which a film of amorphous carbon material is formed on natural graphite, artificial graphite (resin raw materials such as epoxy resins and phenol resins, or petroleum, coal, etc. And the like obtained by firing a pitch-based raw material obtained from the above.
  • the metal composite oxide preferably contains one or both of titanium and lithium, and more preferably contains lithium.
  • the negative electrode active material may further include a material containing at least one element selected from the group consisting of silicon and tin.
  • the material containing at least one element selected from the group consisting of silicon and tin may be a compound containing at least one element selected from the group consisting of silicon or tin alone, silicon and tin.
  • the compound may be an alloy containing at least one element selected from the group consisting of silicon and tin.
  • nickel, copper, iron, cobalt, manganese, zinc, indium, silver An alloy containing at least one selected from the group consisting of titanium, germanium, bismuth, antimony and chromium.
  • the compound containing at least one element selected from the group consisting of silicon and tin may be an oxide, a nitride, or a carbide.
  • silicon oxide such as SiO, SiO 2 , LiSiO, etc.
  • silicon nitride such as Si 3 N 4 and Si 2 N 2 O
  • silicon carbide such as SiC
  • tin oxide such as SnO, SnO 2 and LiSnO.
  • the negative electrode mixture layer 12 preferably contains a carbon material as a negative electrode active material, more preferably contains graphite, more preferably carbon material, silicon and tin. And a mixture with a material containing at least one element selected from the group consisting of: and particularly preferably a mixture of graphite and silicon oxide.
  • the content of the material (silicon oxide) containing at least one element selected from the group consisting of silicon and tin in the mixture is 1% by mass or more, or 3% by mass or more based on the total amount of the mixture, It may be 30% by mass or less.
  • the content of the negative electrode active material may be 80% by mass or more, 85% by mass or more, and 99% by mass or less based on the total amount of the negative electrode mixture layer.
  • the binder and its content may be the same as the binder and its content in the positive electrode mixture layer described above.
  • the negative electrode mixture layer 12 may further contain a thickener in order to adjust the viscosity.
  • the thickener is not particularly limited, but may be carboxymethyl cellulose, methyl cellulose, hydroxymethyl cellulose, ethyl cellulose, polyvinyl alcohol, oxidized starch, phosphorylated starch, casein, salts thereof, and the like.
  • the thickener may be one of these alone or a mixture of two or more.
  • the content of the thickener may be 0.1% by mass or more, preferably 0.2% by mass or more, based on the total amount of the negative electrode mixture layer. More preferably, it is 0.5% by mass or more. From the viewpoint of suppressing a decrease in battery capacity or an increase in resistance between the negative electrode active materials, the content of the thickener may be 5% by mass or less, preferably 3% by mass based on the total amount of the negative electrode mixture layer. % Or less, and more preferably 2% by mass or less.
  • the electrolytic solution contains a compound represented by the following formula (1), an electrolyte salt, and a nonaqueous solvent.
  • R 1 to R 3 each independently represents an alkyl group or a fluorine atom
  • R 4 represents an alkylene group
  • R 5 represents an organic group containing a sulfur atom.
  • the alkyl group represented by R 1 to R 3 may have 1 or more carbon atoms and 3 or less carbon atoms.
  • R 1 to R 3 may be a methyl group, an ethyl group, or a propyl group, and may be linear or branched. At least one of R 1 to R 3 is preferably a fluorine atom.
  • Carbon number of the alkylene group represented by R 4 may be 1 or more, 2 or less, or 5 or less or 4 or less.
  • the alkylene group represented by R 4 may be a methylene group, an ethylene group, a propylene group, a butylene group, or a pentylene group, and may be linear or branched.
  • R 5 may be a group represented by the following formula (2) in one embodiment.
  • R 6 represents an alkyl group.
  • the alkyl group may be the same as the alkyl group represented by R 1 to R 3 described above. * Indicates a bond.
  • R 5 may be a group represented by the following formula (3) in another embodiment.
  • R 7 represents an alkyl group.
  • the alkyl group may be the same as the alkyl group represented by R 1 to R 3 described above. * Indicates a bond.
  • R 5 may be a group represented by the following formula (4) in other embodiments from the viewpoint of further improving the cycle characteristics of the electrochemical device.
  • R 8 represents an alkyl group.
  • the alkyl group may be the same as the alkyl group represented by R 1 to R 3 described above. * Indicates a bond.
  • the content of the compound represented by the formula (1) is preferably 0.001% by mass or more, more preferably 0.001% by mass or more, based on the total amount of the electrolytic solution, from the viewpoint of further improving the cycle characteristics of the electrochemical device. It is 005 mass% or more, More preferably, it is 0.01 mass% or more. From the same viewpoint, the content of the compound represented by the formula (1) is preferably 10% by mass or less, more preferably 7% by mass or less, and further preferably 5% by mass based on the total amount of the electrolytic solution. % Or less, particularly preferably 3% by mass or less.
  • the content of the compound represented by the formula (1) is preferably 0.001 to 10% by mass, 0.001 to 7 based on the total amount of the electrolytic solution, from the viewpoint of further improving the cycle characteristics of the electrochemical device.
  • the electrolyte salt may be a lithium salt, for example.
  • the lithium salt include LiPF 6 , LiBF 4 , LiClO 4 , LiB (C 6 H 5 ) 4 , LiCH 3 SO 3 , CF 3 SO 2 OLi, LiN (SO 2 F) 2 (Li [FSI], lithium bis Fluorosulfonylimide), LiN (SO 2 CF 3 ) 2 (Li [TFSI] (lithium bistrifluoromethanesulfonylimide), and LiN (SO 2 CF 2 CF 3 ) 2.
  • the lithium salt preferably contains LiPF 6 from the viewpoint of further improving solubility in a solvent, charge / discharge characteristics of a secondary battery, output characteristics, cycle characteristics, and the like.
  • the concentration of the electrolyte salt is preferably 0.5 mol / L or more, more preferably 0.7 mol / L or more, still more preferably 0.8 mol / L or more, based on the total amount of the nonaqueous solvent, from the viewpoint of excellent charge / discharge characteristics. Moreover, it is preferably 1.5 mol / L or less, more preferably 1.3 mol / L, and still more preferably 1.2 mol / L or less.
  • Nonaqueous solvents include, for example, ethylene carbonate, propylene carbonate, dimethyl carbonate, diethyl carbonate, methyl ethyl carbonate, ⁇ -butyl lactone, acetonitrile, 1,2-dimethoxyethane, dimethoxymethane, tetrahydrofuran, dioxolane, methylene chloride, methyl acetate, etc. It may be.
  • the non-aqueous solvent may be one kind of these or a mixture of two or more kinds, preferably a mixture of two or more kinds.
  • the electrolytic solution may further contain other materials other than the compound represented by the formula (1), the electrolyte salt, and the solvent.
  • Other materials may be, for example, nitrogen, sulfur, or a heterocyclic compound containing nitrogen and sulfur, a cyclic carboxylic acid ester, a fluorine-containing cyclic carbonate, or other compounds having an unsaturated bond in the molecule.
  • the present inventors have clarified that the cycle characteristics are remarkably improved by applying the above-described electrolytic solution.
  • the present inventors infer the effects of using the above-described electrolyte as follows.
  • the compound represented by the formula (1) forms a stable film on the positive electrode or the negative electrode. Thereby, the fall of the output characteristic resulting from the decomposition product of electrolyte solution depositing on a positive electrode or a negative electrode is suppressed. Furthermore, the capacity
  • the manufacturing method of the nonaqueous electrolyte secondary battery 1 includes a first step of obtaining the positive electrode 6, a second step of obtaining the negative electrode 8, a third step of housing the electrode group 2 in the battery outer package 3, And a fourth step of injecting the electrolytic solution into the battery outer package 3.
  • the positive electrode mixture is treated with a doctor blade method,
  • the positive electrode 6 is obtained by coating on the positive electrode current collector 9 by a dipping method, a spray method or the like, and then volatilizing the dispersion medium.
  • a compression molding step using a roll press may be provided as necessary.
  • the positive electrode mixture layer 10 may be formed as a positive electrode mixture layer having a multilayer structure by performing the above-described steps from application of the positive electrode mixture to volatilization of the dispersion medium a plurality of times.
  • the dispersion medium may be water, 1-methyl-2-pyrrolidone (hereinafter also referred to as NMP), and the like.
  • the second step may be the same as the first step described above, and the method of forming the negative electrode mixture layer 12 on the negative electrode current collector 11 may be the same method as the first step described above. .
  • the separator 7 is sandwiched between the produced positive electrode 6 and negative electrode 8, and the electrode group 2 is formed.
  • the electrode group 2 is accommodated in the battery outer package 3.
  • the electrolytic solution is injected into the battery outer package 3.
  • the electrolytic solution can be prepared, for example, by first dissolving the electrolyte salt in a solvent and then dissolving other materials.
  • the electrochemical device may be a capacitor. Similar to the non-aqueous electrolyte secondary battery 1 described above, the capacitor may include an electrode group including a positive electrode, a negative electrode, and a separator, and a bag-shaped battery outer package that houses the electrode group. The details of each component in the capacitor may be the same as those of the non-aqueous electrolyte secondary battery 1.
  • Example 1 Lithium cobaltate (95% by mass) as a positive electrode active material, fibrous graphite (1% by mass) and acetylene black (AB) (1% by mass) as a conductive agent, and a binder (3% by mass) Were added sequentially and mixed.
  • NMP as a dispersion medium was added and kneaded to prepare a slurry-like positive electrode mixture.
  • a predetermined amount of this positive electrode mixture was uniformly and uniformly applied to an aluminum foil having a thickness of 20 ⁇ m as a positive electrode current collector. Then, after volatilizing the dispersion medium, the dispersion medium was compacted to a density of 3.6 g / cm 3 by pressing to obtain a positive electrode.
  • the positive electrode cut into a 13.5 cm 2 square is sandwiched between polyethylene porous sheets (trade name: Hypore (registered trademark), manufactured by Asahi Kasei Co., Ltd., thickness 30 ⁇ m) as a separator, and further a 14.3 cm 2 square.
  • the electrode group was fabricated by stacking the negative electrodes cut into pieces. This electrode group was accommodated in a container (battery exterior body) formed of an aluminum laminate film (trade name: aluminum laminate film, manufactured by Dai Nippon Printing Co., Ltd.). Subsequently, 1 mL of electrolyte solution was added in the container, the container was heat-welded, and the lithium ion secondary battery for evaluation was produced.
  • 1% by mass of vinylene carbonate (VC) with respect to the total amount of the mixed solution in a mixed solution of ethylene carbonate, dimethyl carbonate and diethyl carbonate containing 1 mol / L LiPF 6 is represented by the following formula (5).
  • the compound A to which 1% by mass (based on the total amount of the electrolytic solution) was added was used.
  • Example 1 a lithium ion secondary battery was produced in the same manner as in Example 1 except that Compound A was not used.
  • FIG. 3 shows the relationship between the number of cycles and the relative value of the discharge capacity.
  • Example 2 A lithium ion secondary battery was produced in the same manner as in Example 1 except that silicon oxide was further added as the negative electrode active material in Example 1 to produce a negative electrode.
  • Example 2 the content of Compound A is 0.1% by mass (Example 3), 0.5% by mass (Example 4), and 3% by mass (Example 5), respectively, based on the total amount of the electrolytic solution.
  • a lithium ion secondary battery was produced in the same manner as in Example 1 except for the change.
  • Example 2 A lithium ion secondary battery was produced in the same manner as in Example 2 except that Compound A was not used in Example 2.
  • Example 3 (Comparative Example 3) In Example 2, instead of Compound A, 4-fluoro-1,3-dioxolan-2-one (fluoroethylene carbonate; FEC) was added in an amount of 1% by mass based on the total amount of the electrolyte solution. Similarly, a lithium ion secondary battery was produced.
  • FEC fluoroethylene carbonate
  • the lithium ion secondary battery of Example 1 using graphite as the negative electrode active material and further applying an electrolytic solution containing 1% by mass of compound A is a comparison in which an electrolytic solution not containing compound A is applied.
  • the evaluation of the cycle characteristics was good.
  • FIG. 4 an implementation in which an anode active material containing graphite and silicon oxide was used, and an electrolytic solution containing 1% by mass, 0.1% by mass, 0.5% by mass, and 3% by mass of Compound A was applied.
  • the lithium ion secondary batteries of Examples 2 to 5 had better evaluation of cycle characteristics than the lithium ion secondary batteries of Comparative Example 2 and Comparative Example 3 to which the electrolyte solution containing no compound A was applied. Although this mechanism is not necessarily clear, since the compound A formed a stable film on the positive electrode or the negative electrode, it was possible to suppress a decrease in output characteristics due to the decomposition product of the electrolyte depositing on the positive electrode or the negative electrode. Conceivable. Further, the stable film formation suppresses side reactions such as electrolyte decomposition in the vicinity of the electrode and a decrease in capacity of the lithium ion secondary battery, and it is considered that the cycle characteristics are improved by these effects.
  • non-aqueous electrolyte secondary battery electrochemical device
  • 6 positive electrode
  • 7 separator
  • 8 negative electrode

Abstract

The present invention provides an electrolytic solution containing a compound represented by formula (1). [In formula (1), R1 to R3 each independently represent an alkyl group or a fluorine atom, R4 represents an alkylene group, and R5 represents an organic group containing a sulfur atom.]

Description

電解液及び電気化学デバイスElectrolytic solution and electrochemical device
　本発明は、電解液及び電気化学デバイスに関する。 The present invention relates to an electrolytic solution and an electrochemical device.
　近年、携帯型電子機器、電気自動車等の普及により、リチウムイオン二次電池に代表される非水電解液二次電池、キャパシタ等の高性能な電気化学デバイスが必要とされている。電気化学デバイスの性能を向上させる手段としては、例えば、電解液に所定の添加剤を添加する方法が検討されている。特許文献１には、サイクル特性及び内部抵抗特性を改善するために、特定のシロキサン化合物を含有させた非水電解液電池用電解液が開示されている。 In recent years, high-performance electrochemical devices such as non-aqueous electrolyte secondary batteries represented by lithium ion secondary batteries and capacitors have been required due to the spread of portable electronic devices and electric vehicles. As a means for improving the performance of an electrochemical device, for example, a method of adding a predetermined additive to an electrolytic solution has been studied. Patent Document 1 discloses a non-aqueous electrolyte battery electrolyte containing a specific siloxane compound in order to improve cycle characteristics and internal resistance characteristics.
特開２０１５－００５３２９号公報JP2015-005329A
　このような電気化学デバイスの耐久性を高め、長期間使用するためには、電気化学デバイスの特性の中でも、特にサイクル特性を向上させることが重要である。しかし、電気化学デバイスの開発においては、サイクル特性の向上の点で更なる改善の余地がある。 In order to enhance the durability of such an electrochemical device and use it for a long period of time, it is important to improve the cycle characteristics among the characteristics of the electrochemical device. However, in the development of electrochemical devices, there is room for further improvement in terms of improving cycle characteristics.
　そこで本発明は、電気化学デバイスのサイクル特性を向上させることができる電解液を提供することを目的とする。また、本発明は、サイクル特性に優れる電気化学デバイスを提供することを目的とする。 Therefore, an object of the present invention is to provide an electrolytic solution that can improve cycle characteristics of an electrochemical device. Another object of the present invention is to provide an electrochemical device having excellent cycle characteristics.
　本発明は、第１の態様として、下記式（１）で表される化合物を含有する、電解液を提供する。
Figure JPOXMLDOC01-appb-C000005
 ［式（１）中、Ｒ１～Ｒ３は、それぞれ独立に、アルキル基又はフッ素原子を示し、Ｒ４はアルキレン基を示し、Ｒ５は、硫黄原子を含む有機基を示す。］ As a first aspect, the present invention provides an electrolytic solution containing a compound represented by the following formula (1).
Figure JPOXMLDOC01-appb-C000005
 [In Formula (1), R 1 to R 3 each independently represents an alkyl group or a fluorine atom, R 4 represents an alkylene group, and R 5 represents an organic group containing a sulfur atom. ]
　Ｒ５は、好ましくは、下記式（２）、式（３）又は式（４）のいずれかで表される基である。
Figure JPOXMLDOC01-appb-C000006
 ［式（２）中、Ｒ６はアルキル基を示し、＊は結合手を示す。］
Figure JPOXMLDOC01-appb-C000007
 ［式（３）中、Ｒ７はアルキル基を示し、＊は結合手を示す。］
Figure JPOXMLDOC01-appb-C000008
 ［式（４）中、Ｒ８はアルキル基を示し、＊は結合手を示す。］ R 5 is preferably a group represented by any of the following formula (2), formula (3) or formula (4).
Figure JPOXMLDOC01-appb-C000006
 [In formula (2), R 6 represents an alkyl group, and * represents a bond. ]
Figure JPOXMLDOC01-appb-C000007
 [In formula (3), R 7 represents an alkyl group, and * represents a bond. ]
Figure JPOXMLDOC01-appb-C000008
 [In formula (4), R 8 represents an alkyl group, and * represents a bond. ]
　Ｒ１～Ｒ３の少なくとも１つは、好ましくはフッ素原子である。 At least one of R 1 to R 3 is preferably a fluorine atom.
　式（１）で表される化合物の含有量は、好ましくは、電解液全量を基準として１０質量％以下である。 The content of the compound represented by the formula (1) is preferably 10% by mass or less based on the total amount of the electrolytic solution.
　本発明は、第２の態様として、正極と、負極と、上記の電解液と、を備える電気化学デバイスを提供する。 The present invention provides, as a second aspect, an electrochemical device comprising a positive electrode, a negative electrode, and the above electrolytic solution.
　負極は、好ましくは炭素材料を含有する。炭素材料は、好ましくは黒鉛を含有する。負極は、好ましくは、ケイ素及びスズからなる群の少なくとも１種の元素を含む材料を更に含有する。 The negative electrode preferably contains a carbon material. The carbon material preferably contains graphite. The negative electrode preferably further contains a material containing at least one element of the group consisting of silicon and tin.
　電気化学デバイスは、好ましくは非水電解液二次電池又はキャパシタである。 The electrochemical device is preferably a non-aqueous electrolyte secondary battery or a capacitor.
　本発明によれば、電気化学デバイスのサイクル特性を向上させることができる電解液を提供することができる。また、本発明によれば、サイクル特性に優れる電気化学デバイスを提供することができる。 According to the present invention, it is possible to provide an electrolytic solution capable of improving the cycle characteristics of an electrochemical device. Moreover, according to this invention, the electrochemical device excellent in cycling characteristics can be provided.
一実施形態に係る電気化学デバイスとしての非水電解液二次電池を示す斜視図である。It is a perspective view which shows the nonaqueous electrolyte secondary battery as an electrochemical device which concerns on one Embodiment. 図１に示した二次電池の電極群を示す分解斜視図である。It is a disassembled perspective view which shows the electrode group of the secondary battery shown in FIG. 実施例１及び比較例１のサイクル特性の評価結果を示すグラフである。5 is a graph showing evaluation results of cycle characteristics of Example 1 and Comparative Example 1. 実施例２～５及び比較例２～３のサイクル特性の評価結果を示すグラフである。6 is a graph showing evaluation results of cycle characteristics of Examples 2 to 5 and Comparative Examples 2 to 3.
　以下、図面を適宜参照しながら、本発明の実施形態について説明する。ただし、本発明は以下の実施形態に限定されるものではない。 Hereinafter, embodiments of the present invention will be described with appropriate reference to the drawings. However, the present invention is not limited to the following embodiments.
　図１は、一実施形態に係る電気化学デバイスを示す斜視図である。本実施形態において、電気化学デバイスは非水電解液二次電池である。図１に示すように、非水電解液二次電池１は、正極、負極及びセパレータから構成される電極群２と、電極群２を収容する袋状の電池外装体３とを備えている。正極及び負極には、それぞれ正極集電タブ４及び負極集電タブ５が設けられている。正極集電タブ４及び負極集電タブ５は、それぞれ正極及び負極が非水電解液二次電池１の外部と電気的に接続可能なように、電池外装体３の内部から外部へ突き出している。電池外装体３内には、電解液（図示せず）が充填されている。非水電解液二次電池１は、上述したようないわゆる「ラミネート型」以外の形状の電池（コイン型、円筒型、積層型等）であってもよい。 FIG. 1 is a perspective view showing an electrochemical device according to an embodiment. In this embodiment, the electrochemical device is a non-aqueous electrolyte secondary battery. As shown in FIG. 1, the nonaqueous electrolyte secondary battery 1 includes an electrode group 2 composed of a positive electrode, a negative electrode, and a separator, and a bag-shaped battery exterior body 3 that houses the electrode group 2. A positive electrode current collecting tab 4 and a negative electrode current collecting tab 5 are provided on the positive electrode and the negative electrode, respectively. The positive electrode current collecting tab 4 and the negative electrode current collecting tab 5 protrude from the inside of the battery outer package 3 to the outside so that the positive electrode and the negative electrode can be electrically connected to the outside of the nonaqueous electrolyte secondary battery 1, respectively. . The battery outer package 3 is filled with an electrolytic solution (not shown). The non-aqueous electrolyte secondary battery 1 may be a battery (coin type, cylindrical type, laminated type, etc.) having a shape other than the so-called “laminate type” as described above.
　電池外装体３は、例えばラミネートフィルムで形成された容器であってよい。ラミネートフィルムは、例えば、ポリエチレンテレフタレート（ＰＥＴ）フィルム等の樹脂フィルムと、アルミニウム、銅、ステンレス鋼等の金属箔と、ポリプロピレン等のシーラント層とがこの順で積層された積層フィルムであってよい。 The battery outer package 3 may be a container formed of a laminate film, for example. The laminate film may be a laminate film in which a resin film such as a polyethylene terephthalate (PET) film, a metal foil such as aluminum, copper, and stainless steel, and a sealant layer such as polypropylene are laminated in this order.
　図２は、図１に示した非水電解液二次電池１における電極群２の一実施形態を示す分解斜視図である。図２に示すように、電極群２は、正極６と、セパレータ７と、負極８とをこの順に備えている。正極６及び負極８は、正極合剤層１０側及び負極合剤層１２側の面がそれぞれセパレータ７と対向するように配置されている。 FIG. 2 is an exploded perspective view showing an embodiment of the electrode group 2 in the nonaqueous electrolyte secondary battery 1 shown in FIG. As shown in FIG. 2, the electrode group 2 includes a positive electrode 6, a separator 7, and a negative electrode 8 in this order. The positive electrode 6 and the negative electrode 8 are arranged so that the surfaces on the positive electrode mixture layer 10 side and the negative electrode mixture layer 12 side face the separator 7, respectively.
　正極６は、正極集電体９と、正極集電体９上に設けられた正極合剤層１０とを備えている。正極集電体９には、正極集電タブ４が設けられている。 The positive electrode 6 includes a positive electrode current collector 9 and a positive electrode mixture layer 10 provided on the positive electrode current collector 9. The positive electrode current collector 9 is provided with a positive electrode current collector tab 4.
　正極集電体９は、例えば、アルミニウム、チタン、ステンレス、ニッケル、焼成炭素、導電性高分子、導電性ガラス等で形成されている。正極集電体９は、接着性、導電性及び耐酸化性向上の目的で、アルミニウム、銅等の表面にカーボン、ニッケル、チタン、銀等で処理が施されたものであってもよい。正極集電体９の厚さは、電極強度及びエネルギー密度の点から、例えば１～５０μｍである。 The positive electrode current collector 9 is made of, for example, aluminum, titanium, stainless steel, nickel, baked carbon, conductive polymer, conductive glass, or the like. The positive electrode current collector 9 may have a surface such as aluminum or copper that has been treated with carbon, nickel, titanium, silver, or the like for the purpose of improving adhesiveness, conductivity, and oxidation resistance. The thickness of the positive electrode current collector 9 is, for example, 1 to 50 μm from the viewpoint of electrode strength and energy density.
　正極合剤層１０は、一実施形態において、正極活物質と、導電剤と、結着剤とを含有する。正極合剤層１０の厚さは、例えば２０～２００μｍである。 In one embodiment, the positive electrode mixture layer 10 contains a positive electrode active material, a conductive agent, and a binder. The thickness of the positive electrode mixture layer 10 is, for example, 20 to 200 μm.
　正極活物質は、例えばリチウム酸化物であってよい。リチウム酸化物は、例えば、ＬｉｘＣｏＯ２、ＬｉｘＮｉＯ２、ＬｉｘＭｎＯ２、ＬｉｘＣｏｙＮｉ１－ｙＯ２、ＬｉｘＣｏｙＭ１－ｙＯｚ、ＬｉｘＮｉ１－ｙＭｙＯｚ、ＬｉｘＭｎ２Ｏ４及びＬｉｘＭｎ２－ｙＭｙＯ４（各式中、Ｍは、Ｎａ、Ｍｇ、Ｓｃ、Ｙ、Ｍｎ、Ｆｅ、Ｃｏ、Ｃｕ、Ｚｎ、Ａｌ、Ｃｒ、Ｐｂ、Ｓｂ、Ｖ及びＢからなる群より選ばれる少なくとも１種の元素を示す（ただし、Ｍは、各式中の他の元素と異なる元素である）。ｘ＝０～１．２、ｙ＝０～０．９、ｚ＝２．０～２．３である。）が挙げられる。 The positive electrode active material may be lithium oxide, for example. Lithium oxide is, for example, Li x CoO 2, Li x NiO 2, Li x MnO 2, Li x Co y Ni 1-y O 2, Li x Co y M 1-y O z, Li x Ni 1-y M y O z , Li x Mn 2 O 4 and Li x Mn 2-y M y O 4 (wherein M is Na, Mg, Sc, Y, Mn, Fe, Co, Cu, Zn, Al, Represents at least one element selected from the group consisting of Cr, Pb, Sb, V and B (where M is an element different from the other elements in each formula), x = 0 to 1.2, y = 0 to 0.9, z = 2.0 to 2.3).
　正極活物質の含有量は、正極合剤層全量を基準として、８０質量％以上、又は８５質量％以上であってよく、９９質量％以下であってよい。 The content of the positive electrode active material may be 80% by mass or more, 85% by mass or more, and 99% by mass or less based on the total amount of the positive electrode mixture layer.
　導電剤は、アセチレンブラック、ケッチェンブラック等のカーボンブラック、黒鉛、グラフェン等の炭素材料、カーボンナノチューブなどであってよい。導電剤の含有量は、正極合剤層全量を基準として、例えば、０．０１質量％以上、０．１質量％以上、又は１質量％以上であってよく、５０質量％以下、３０質量％以下、又は１５質量％以下であってよい。 The conductive agent may be a carbon black such as acetylene black or ketjen black, a carbon material such as graphite or graphene, or a carbon nanotube. The content of the conductive agent may be, for example, 0.01% by mass or more, 0.1% by mass or more, or 1% by mass or more based on the total amount of the positive electrode mixture layer, and is 50% by mass or less, 30% by mass. Or 15% by mass or less.
　結着剤は、例えば、ポリエチレン、ポリプロピレン、ポリエチレンテレフタレート、ポリメチルメタクリレート、ポリイミド、芳香族ポリアミド、セルロース、ニトロセルロース等の樹脂；ＳＢＲ（スチレン－ブタジエンゴム）、ＮＢＲ（アクリロニトリル－ブタジエンゴム）、フッ素ゴム、イソプレンゴム、ブタジエンゴム、エチレン－プロピレンゴム等のゴム；スチレン・ブタジエン・スチレンブロック共重合体又はその水素添加物、ＥＰＤＭ（エチレン・プロピレン・ジエン三元共重合体）、スチレン・エチレン・ブタジエン・エチレン共重合体、スチレン・イソプレン・スチレンブロック共重合体又はその水素添加物等の熱可塑性エラストマー；シンジオタクチック－１、２－ポリブタジエン、ポリ酢酸ビニル、エチレン・酢酸ビニル共重合体、プロピレン・α－オレフィン共重合体等の軟質樹脂；ポリフッ化ビニリデン（ＰＶＤＦ）、ポリテトラフルオロエチレン、フッ素化ポリフッ化ビニリデン、ポリテトラフルオロエチレン・エチレン共重合体、ポリテトラフルオロエチレン・フッ化ビニリデン共重合体等のフッ素含有樹脂；ニトリル基含有モノマーをモノマー単位として有する樹脂；アルカリ金属イオン（例えばリチウムイオン）のイオン伝導性を有する高分子組成物などが挙げられる。 Examples of the binder include resins such as polyethylene, polypropylene, polyethylene terephthalate, polymethyl methacrylate, polyimide, aromatic polyamide, cellulose, and nitrocellulose; SBR (styrene-butadiene rubber), NBR (acrylonitrile-butadiene rubber), fluorine rubber Rubber such as isoprene rubber, butadiene rubber, ethylene-propylene rubber; styrene / butadiene / styrene block copolymer or hydrogenated product thereof, EPDM (ethylene / propylene / diene terpolymer), styrene / ethylene / butadiene / Thermoplastic elastomers such as ethylene copolymers, styrene / isoprene / styrene block copolymers or hydrogenated products thereof; syndiotactic-1, 2-polybutadiene, polyvinyl acetate, ethylene / vinyl acetate Copolymer, propylene / α-olefin copolymer, etc .; polyvinylidene fluoride (PVDF), polytetrafluoroethylene, fluorinated polyvinylidene fluoride, polytetrafluoroethylene / ethylene copolymer, polytetrafluoroethylene Fluorine-containing resins such as vinylidene fluoride copolymers; resins having nitrile group-containing monomers as monomer units; polymer compositions having ion conductivity of alkali metal ions (for example, lithium ions).
　結着剤の含有量は、正極合剤層全量を基準として、例えば、０．１質量％以上、１質量％以上、又は１．５質量％以上であってよく、３０質量％以下、２０質量％以下、又は１０質量％以下であってよい。 The content of the binder may be, for example, 0.1% by mass or more, 1% by mass or more, or 1.5% by mass or more based on the total amount of the positive electrode mixture layer, and is 30% by mass or less, 20% by mass. % Or less, or 10 mass% or less.
　セパレータ７は、正極６及び負極８間を電子的には絶縁する一方でイオンを透過させ、かつ、正極６側における酸化性及び負極８側における還元性に対する耐性を備えるものであれば、特に制限されない。このようなセパレータ７の材料（材質）としては、樹脂、無機物等が挙げられる。 The separator 7 is particularly limited as long as it electrically insulates between the positive electrode 6 and the negative electrode 8 and allows ions to pass therethrough and has resistance to oxidation on the positive electrode 6 side and reduction on the negative electrode 8 side. Not. Examples of the material (material) of the separator 7 include resins and inorganic substances.
　樹脂としては、オレフィン系ポリマー、フッ素系ポリマー、セルロース系ポリマー、ポリイミド、ナイロン等が挙げられる。セパレータ７は、電解液に対して安定で、保液性に優れる観点から、好ましくは、ポリエチレン、ポリプロピレン等のポリオレフィンで形成された多孔質シート又は不織布等である。 Examples of the resin include olefin polymers, fluorine polymers, cellulose polymers, polyimide, nylon, and the like. The separator 7 is preferably a porous sheet or a nonwoven fabric formed of polyolefin such as polyethylene or polypropylene from the viewpoint of being stable with respect to the electrolytic solution and having excellent liquid retention.
　無機物としては、アルミナ、二酸化珪素等の酸化物、窒化アルミニウム、窒化珪素等の窒化物、硫酸バリウム、硫酸カルシウム等の硫酸塩が挙げられる。セパレータ７は、例えば、不織布、織布、微多孔性フィルム等の薄膜状基材に、繊維状又は粒子状の無機物を付着させたセパレータであってよい。 Examples of the inorganic substance include oxides such as alumina and silicon dioxide, nitrides such as aluminum nitride and silicon nitride, and sulfates such as barium sulfate and calcium sulfate. The separator 7 may be a separator in which a fibrous or particulate inorganic substance is adhered to a thin film substrate such as a nonwoven fabric, a woven fabric, or a microporous film.
　負極８は、負極集電体１１と、負極集電体１１上に設けられた負極合剤層１２とを備えている。負極集電体１１には、負極集電タブ５が設けられている。 The negative electrode 8 includes a negative electrode current collector 11 and a negative electrode mixture layer 12 provided on the negative electrode current collector 11. The negative electrode current collector 11 is provided with a negative electrode current collector tab 5.
　負極集電体１１は、銅、ステンレス、ニッケル、アルミニウム、チタン、焼成炭素、導電性高分子、導電性ガラス、アルミニウム－カドミウム合金等で形成されている。負極集電体１１は、接着性、導電性、耐還元性向上の目的で、銅、アルミニウム等の表面にカーボン、ニッケル、チタン、銀等で処理が施されたものであってもよい。負極集電体１１の厚さは、電極強度及びエネルギー密度の点から、例えば１～５０μｍである。 The negative electrode current collector 11 is made of copper, stainless steel, nickel, aluminum, titanium, baked carbon, conductive polymer, conductive glass, aluminum-cadmium alloy, or the like. The negative electrode current collector 11 may be one in which the surface of copper, aluminum or the like is treated with carbon, nickel, titanium, silver or the like for the purpose of improving adhesiveness, conductivity, and reduction resistance. The thickness of the negative electrode current collector 11 is, for example, 1 to 50 μm from the viewpoint of electrode strength and energy density.
　負極合剤層１２は、例えば、負極活物質と、結着剤とを含有する。 The negative electrode mixture layer 12 contains, for example, a negative electrode active material and a binder.
　負極活物質は、リチウムイオンを吸蔵及び放出可能な物質であれば特に制限されない。負極活物質としては、例えば、炭素材料、金属複合酸化物、錫、ゲルマニウム、ケイ素等の第四族元素の酸化物又は窒化物、リチウムの単体、リチウムアルミニウム合金等のリチウム合金、Ｓｎ、Ｓｉ等のリチウムと合金を形成可能な金属などが挙げられる。負極活物質は、安全性の観点からは、好ましくは炭素材料及び金属複合酸化物からなる群より選択される少なくとも１種である。負極活物質は、これらの１種単独又は２種以上の混合物であってよい。負極活物質の形状は、例えば、粒子状であってよい。 The negative electrode active material is not particularly limited as long as it is a material capable of occluding and releasing lithium ions. Examples of the negative electrode active material include carbon materials, metal composite oxides, oxides or nitrides of Group 4 elements such as tin, germanium, and silicon, lithium alone, lithium alloys such as lithium aluminum alloys, Sn, Si, and the like And metals capable of forming an alloy with lithium. The negative electrode active material is preferably at least one selected from the group consisting of a carbon material and a metal composite oxide from the viewpoint of safety. The negative electrode active material may be one of these alone or a mixture of two or more. The shape of the negative electrode active material may be, for example, a particulate shape.
　炭素材料としては、非晶質炭素材料、天然黒鉛、天然黒鉛に非晶質炭素材料の被膜を形成した複合炭素材料、人造黒鉛（エポキシ樹脂、フェノール樹脂等の樹脂原料、又は、石油、石炭等から得られるピッチ系原料を焼成して得られるもの）などが挙げられる。金属複合酸化物は、高電流密度充放電特性の観点からは、好ましくはチタン及びリチウムのいずれか一方又は両方を含有し、より好ましくはリチウムを含有する。 Examples of carbon materials include amorphous carbon materials, natural graphite, composite carbon materials in which a film of amorphous carbon material is formed on natural graphite, artificial graphite (resin raw materials such as epoxy resins and phenol resins, or petroleum, coal, etc. And the like obtained by firing a pitch-based raw material obtained from the above. From the viewpoint of high current density charge / discharge characteristics, the metal composite oxide preferably contains one or both of titanium and lithium, and more preferably contains lithium.
　負極活物質には、ケイ素及びスズからなる群より選ばれる少なくとも１種の元素を含む材料が更に含まれていてもよい。ケイ素及びスズからなる群より選ばれる少なくとも１種の元素を含む材料は、ケイ素又はスズの単体、ケイ素及びスズからなる群より選ばれる少なくとも１種の元素を含む化合物であってよい。当該化合物は、ケイ素及びスズからなる群より選ばれる少なくとも１種の元素を含む合金であってよく、例えば、ケイ素及びスズの他に、ニッケル、銅、鉄、コバルト、マンガン、亜鉛、インジウム、銀、チタン、ゲルマニウム、ビスマス、アンチモン及びクロムからなる群より選ばれる少なくとも１種を含む合金である。ケイ素及びスズからなる群より選ばれる少なくとも１種の元素を含む化合物は、酸化物、窒化物、又は炭化物であってもよく、具体的には、例えば、ＳｉＯ、ＳｉＯ２、ＬｉＳｉＯ等のケイ素酸化物、Ｓｉ３Ｎ４、Ｓｉ２Ｎ２Ｏ等のケイ素窒化物、ＳｉＣ等のケイ素炭化物、ＳｎＯ、ＳｎＯ２、ＬｉＳｎＯ等のスズ素酸化物などであってよい。 The negative electrode active material may further include a material containing at least one element selected from the group consisting of silicon and tin. The material containing at least one element selected from the group consisting of silicon and tin may be a compound containing at least one element selected from the group consisting of silicon or tin alone, silicon and tin. The compound may be an alloy containing at least one element selected from the group consisting of silicon and tin. For example, in addition to silicon and tin, nickel, copper, iron, cobalt, manganese, zinc, indium, silver , An alloy containing at least one selected from the group consisting of titanium, germanium, bismuth, antimony and chromium. The compound containing at least one element selected from the group consisting of silicon and tin may be an oxide, a nitride, or a carbide. Specifically, for example, silicon oxide such as SiO, SiO 2 , LiSiO, etc. And silicon nitride such as Si 3 N 4 and Si 2 N 2 O, silicon carbide such as SiC, and tin oxide such as SnO, SnO 2 and LiSnO.
　負極合剤層１２は、電気化学デバイスのサイクル特性を更に向上させる観点から、負極活物質として、好ましくは炭素材料を含み、より好ましくは黒鉛を含み、更に好ましくは、炭素材料と、ケイ素及びスズからなる群より選ばれる少なくとも１種の元素を含む材料との混合物を含み、特に好ましくは、黒鉛とケイ素酸化物との混合物を含む。当該混合物におけるケイ素及びスズからなる群より選ばれる少なくとも１種の元素を含む材料（ケイ素酸化物）の含有量は、当該混合物全量を基準として、１質量％以上、又は３質量％以上であってよく、３０質量％以下であってよい。 From the viewpoint of further improving the cycle characteristics of the electrochemical device, the negative electrode mixture layer 12 preferably contains a carbon material as a negative electrode active material, more preferably contains graphite, more preferably carbon material, silicon and tin. And a mixture with a material containing at least one element selected from the group consisting of: and particularly preferably a mixture of graphite and silicon oxide. The content of the material (silicon oxide) containing at least one element selected from the group consisting of silicon and tin in the mixture is 1% by mass or more, or 3% by mass or more based on the total amount of the mixture, It may be 30% by mass or less.
　負極活物質の含有量は、負極合剤層全量を基準として、８０質量％以上、又は８５質量％以上であってよく、９９質量％以下であってよい。 The content of the negative electrode active material may be 80% by mass or more, 85% by mass or more, and 99% by mass or less based on the total amount of the negative electrode mixture layer.
　結着剤及びその含有量は、上述した正極合剤層における結着剤及びその含有量と同様であってよい。 The binder and its content may be the same as the binder and its content in the positive electrode mixture layer described above.
　負極合剤層１２は、粘度を調節するために増粘剤を更に含有してもよい。増粘剤は、特に制限されないが、カルボキシメチルセルロース、メチルセルロース、ヒドロキシメチルセルロース、エチルセルロース、ポリビニルアルコール、酸化スターチ、リン酸化スターチ、カゼイン、これらの塩等であってよい。増粘剤は、これらの１種単独又は２種以上の混合物であってよい。 The negative electrode mixture layer 12 may further contain a thickener in order to adjust the viscosity. The thickener is not particularly limited, but may be carboxymethyl cellulose, methyl cellulose, hydroxymethyl cellulose, ethyl cellulose, polyvinyl alcohol, oxidized starch, phosphorylated starch, casein, salts thereof, and the like. The thickener may be one of these alone or a mixture of two or more.
　負極合剤層１２が増粘剤を含む場合、その含有量は特に制限されない。増粘剤の含有量は、負極合剤層の塗布性の観点からは、負極合剤層全量を基準として、０．１質量％以上であってよく、好ましくは０．２質量％以上であり、より好ましくは０．５質量％以上である。増粘剤の含有量は、電池容量の低下又は負極活物質間の抵抗の上昇を抑制する観点からは、負極合剤層全量を基準として、５質量％以下であってよく、好ましくは３質量％以下であり、より好ましくは２質量％以下である。 When the negative electrode mixture layer 12 contains a thickener, the content is not particularly limited. From the viewpoint of applicability of the negative electrode mixture layer, the content of the thickener may be 0.1% by mass or more, preferably 0.2% by mass or more, based on the total amount of the negative electrode mixture layer. More preferably, it is 0.5% by mass or more. From the viewpoint of suppressing a decrease in battery capacity or an increase in resistance between the negative electrode active materials, the content of the thickener may be 5% by mass or less, preferably 3% by mass based on the total amount of the negative electrode mixture layer. % Or less, and more preferably 2% by mass or less.
　電解液は、一実施形態において、下記式（１）で表される化合物と、電解質塩と、非水溶媒とを含有する。
Figure JPOXMLDOC01-appb-C000009
 　式（１）中、Ｒ１～Ｒ３は、それぞれ独立に、アルキル基又はフッ素原子を示し、Ｒ４はアルキレン基を示し、Ｒ５は、硫黄原子を含む有機基を示す。 In one embodiment, the electrolytic solution contains a compound represented by the following formula (1), an electrolyte salt, and a nonaqueous solvent.
Figure JPOXMLDOC01-appb-C000009
 In the formula (1), R 1 to R 3 each independently represents an alkyl group or a fluorine atom, R 4 represents an alkylene group, and R 5 represents an organic group containing a sulfur atom.
　Ｒ１～Ｒ３で表されるアルキル基の炭素数は、１以上であってよく、３以下であってよい。Ｒ１～Ｒ３は、メチル基、エチル基、又はプロピル基であってよく、直鎖状でも分岐状でもよい。Ｒ１～Ｒ３の少なくとも１つは、好ましくはフッ素原子である。 The alkyl group represented by R 1 to R 3 may have 1 or more carbon atoms and 3 or less carbon atoms. R 1 to R 3 may be a methyl group, an ethyl group, or a propyl group, and may be linear or branched. At least one of R 1 to R 3 is preferably a fluorine atom.
　Ｒ４で表されるアルキレン基の炭素数は、１以上又は２以上であってよく、５以下又は４以下であってよい。Ｒ４で表されるアルキレン基は、メチレン基、エチレン基、プロピレン基、ブチレン基、又はペンチレン基であってよく、直鎖状でも分岐状でもよい。 Carbon number of the alkylene group represented by R 4 may be 1 or more, 2 or less, or 5 or less or 4 or less. The alkylene group represented by R 4 may be a methylene group, an ethylene group, a propylene group, a butylene group, or a pentylene group, and may be linear or branched.
　Ｒ５は、電気化学デバイスのサイクル特性を更に向上させる観点から、一実施形態において、下記式（２）で表される基であってよい。
Figure JPOXMLDOC01-appb-C000010
 　式（２）中、Ｒ６はアルキル基を示す。アルキル基は、上述したＲ１～Ｒ３で表されるアルキル基と同様であってよい。＊は結合手を示す。 From the viewpoint of further improving the cycle characteristics of the electrochemical device, R 5 may be a group represented by the following formula (2) in one embodiment.
Figure JPOXMLDOC01-appb-C000010
 In formula (2), R 6 represents an alkyl group. The alkyl group may be the same as the alkyl group represented by R 1 to R 3 described above. * Indicates a bond.
　Ｒ５は、電気化学デバイスのサイクル特性を更に向上させる観点から、他の実施形態において、下記式（３）で表される基であってもよい。
Figure JPOXMLDOC01-appb-C000011
 式（３）中、Ｒ７はアルキル基を示す。アルキル基は、上述したＲ１～Ｒ３で表されるアルキル基と同様であってよい。＊は結合手を示す。 From the viewpoint of further improving the cycle characteristics of the electrochemical device, R 5 may be a group represented by the following formula (3) in another embodiment.
Figure JPOXMLDOC01-appb-C000011
 In formula (3), R 7 represents an alkyl group. The alkyl group may be the same as the alkyl group represented by R 1 to R 3 described above. * Indicates a bond.
　Ｒ５は、電気化学デバイスのサイクル特性を更に向上させる観点から、他の実施形態において、下記式（４）で表される基であってもよい。
Figure JPOXMLDOC01-appb-C000012
 式（４）中、Ｒ８はアルキル基を示す。アルキル基は、上述したＲ１～Ｒ３で表されるアルキル基と同様であってよい。＊は結合手を示す。 R 5 may be a group represented by the following formula (4) in other embodiments from the viewpoint of further improving the cycle characteristics of the electrochemical device.
Figure JPOXMLDOC01-appb-C000012
 In the formula (4), R 8 represents an alkyl group. The alkyl group may be the same as the alkyl group represented by R 1 to R 3 described above. * Indicates a bond.
　式（１）で表される化合物の含有量は、電気化学デバイスのサイクル特性を更に向上させる観点から、電解液全量を基準として、好ましくは０．００１質量％以上であり、より好ましくは０．００５質量％以上であり、更に好ましくは０．０１質量％以上である。式（１）で表される化合物の含有量は、同様の観点から、電解液全量を基準として、好ましくは１０質量％以下であり、より好ましくは７質量％以下であり、更に好ましくは５質量％以下、特に好ましくは３質量％以下である。式（１）で表される化合物の含有量は、電気化学デバイスのサイクル特性を更に向上させる観点から、電解液全量を基準として、好ましくは、０．００１～１０質量％、０．００１～７質量％、０．００１～５質量％、０．００１～３質量％０．００５～１０質量％、０．００５～７質量％、０．００５～５質量％、０．００５～３質量％、０．０１～１０質量％、０．０１～７質量％、０．０１～５質量％、又は０．０１～３質量％である。 The content of the compound represented by the formula (1) is preferably 0.001% by mass or more, more preferably 0.001% by mass or more, based on the total amount of the electrolytic solution, from the viewpoint of further improving the cycle characteristics of the electrochemical device. It is 005 mass% or more, More preferably, it is 0.01 mass% or more. From the same viewpoint, the content of the compound represented by the formula (1) is preferably 10% by mass or less, more preferably 7% by mass or less, and further preferably 5% by mass based on the total amount of the electrolytic solution. % Or less, particularly preferably 3% by mass or less. The content of the compound represented by the formula (1) is preferably 0.001 to 10% by mass, 0.001 to 7 based on the total amount of the electrolytic solution, from the viewpoint of further improving the cycle characteristics of the electrochemical device. Mass%, 0.001-5 mass%, 0.001-3 mass% 0.005-10 mass%, 0.005-7 mass%, 0.005-5 mass%, 0.005-3 mass%, 0.01 to 10% by mass, 0.01 to 7% by mass, 0.01 to 5% by mass, or 0.01 to 3% by mass.
　電解質塩は、例えばリチウム塩であってよい。リチウム塩は、例えば、ＬｉＰＦ６、ＬｉＢＦ４、ＬｉＣｌＯ４、ＬｉＢ（Ｃ６Ｈ５）４、ＬｉＣＨ３ＳＯ３、ＣＦ３ＳＯ２ＯＬｉ、ＬｉＮ（ＳＯ２Ｆ）２（Ｌｉ［ＦＳＩ］、リチウムビスフルオロスルホニルイミド）、ＬｉＮ（ＳＯ２ＣＦ３）２（Ｌｉ［ＴＦＳＩ］（リチウムビストリフルオロメタンスルホニルイミド）、及びＬｉＮ（ＳＯ２ＣＦ２ＣＦ３）２からなる群より選ばれる少なくとも１種であってよい。リチウム塩は、溶媒に対する溶解性、二次電池の充放電特性、出力特性、サイクル特性等に更に優れる観点から、好ましくはＬｉＰＦ６を含む。 The electrolyte salt may be a lithium salt, for example. Examples of the lithium salt include LiPF 6 , LiBF 4 , LiClO 4 , LiB (C 6 H 5 ) 4 , LiCH 3 SO 3 , CF 3 SO 2 OLi, LiN (SO 2 F) 2 (Li [FSI], lithium bis Fluorosulfonylimide), LiN (SO 2 CF 3 ) 2 (Li [TFSI] (lithium bistrifluoromethanesulfonylimide), and LiN (SO 2 CF 2 CF 3 ) 2. The lithium salt preferably contains LiPF 6 from the viewpoint of further improving solubility in a solvent, charge / discharge characteristics of a secondary battery, output characteristics, cycle characteristics, and the like.
　電解質塩の濃度は、充放電特性に優れる観点から、非水溶媒全量を基準として、好ましくは０．５ｍｏｌ／Ｌ以上、より好ましくは０．７ｍｏｌ／Ｌ以上、更に好ましくは０．８ｍｏｌ／Ｌ以上であり、また、好ましくは１．５ｍｏｌ／Ｌ以下、より好ましくは１．３ｍｏｌ／Ｌ、更に好ましくは１．２ｍｏｌ／Ｌ以下である。 The concentration of the electrolyte salt is preferably 0.5 mol / L or more, more preferably 0.7 mol / L or more, still more preferably 0.8 mol / L or more, based on the total amount of the nonaqueous solvent, from the viewpoint of excellent charge / discharge characteristics. Moreover, it is preferably 1.5 mol / L or less, more preferably 1.3 mol / L, and still more preferably 1.2 mol / L or less.
　非水溶媒は、例えば、エチレンカーボネート、プロピレンカーボネート、ジメチルカーボネート、ジエチルカーボネート、メチルエチルカーボネート、γ－ブチルラクトン、アセトニトリル、１，２－ジメトキシエタン、ジメトキシメタン、テトラヒドロフラン、ジオキソラン、塩化メチレン、酢酸メチル等であってよい。非水溶媒は、これらの１種単独又は２種以上の混合物であってよく、好ましくは２種以上の混合物である。 Nonaqueous solvents include, for example, ethylene carbonate, propylene carbonate, dimethyl carbonate, diethyl carbonate, methyl ethyl carbonate, γ-butyl lactone, acetonitrile, 1,2-dimethoxyethane, dimethoxymethane, tetrahydrofuran, dioxolane, methylene chloride, methyl acetate, etc. It may be. The non-aqueous solvent may be one kind of these or a mixture of two or more kinds, preferably a mixture of two or more kinds.
　電解液は、式（１）で表される化合物、電解質塩及び溶媒以外のその他の材料を更に含有してもよい。その他の材料は、例えば、窒素、硫黄、又は窒素及び硫黄を含有する複素環化合物、環状カルボン酸エステル、フッ素含有環状カーボネート、その他の分子内に不飽和結合を有する化合物等であってよい。 The electrolytic solution may further contain other materials other than the compound represented by the formula (1), the electrolyte salt, and the solvent. Other materials may be, for example, nitrogen, sulfur, or a heterocyclic compound containing nitrogen and sulfur, a cyclic carboxylic acid ester, a fluorine-containing cyclic carbonate, or other compounds having an unsaturated bond in the molecule.
　本発明者らは、様々な構造および官能基を有する化合物を検討した結果、上述した電解液を適用することによって顕著にサイクル特性が向上することを明らかにした。本発明者らは、上述した電解液を用いることによる作用効果を以下のように推察している。式（１）で表される化合物は、正極又は負極上で安定な被膜を形成する。これにより、電解液の分解物が正極又は負極上に堆積することに起因する出力特性の低下が抑制される。さらに、電解質塩の分解に起因する容量低下及び抵抗増加が抑制される。その結果、非水電解液二次電池１のサイクル特性が向上する。さらに、式（１）で表される化合物自身がＳｉを含む骨格を有していることにより、化合物由来のガス発生が少なくなり、非水電解液二次電池１を高温保存した場合の体積膨張を抑制することができる。 As a result of studying compounds having various structures and functional groups, the present inventors have clarified that the cycle characteristics are remarkably improved by applying the above-described electrolytic solution. The present inventors infer the effects of using the above-described electrolyte as follows. The compound represented by the formula (1) forms a stable film on the positive electrode or the negative electrode. Thereby, the fall of the output characteristic resulting from the decomposition product of electrolyte solution depositing on a positive electrode or a negative electrode is suppressed. Furthermore, the capacity | capacitance fall and resistance increase resulting from decomposition | disassembly of electrolyte salt are suppressed. As a result, the cycle characteristics of the nonaqueous electrolyte secondary battery 1 are improved. Further, since the compound represented by the formula (1) itself has a skeleton containing Si, generation of gas derived from the compound is reduced, and volume expansion when the nonaqueous electrolyte secondary battery 1 is stored at high temperature is reduced. Can be suppressed.
　続いて、非水電解液二次電池１の製造方法を説明する。非水電解液二次電池１の製造方法は、正極６を得る第１の工程と、負極８を得る第２の工程と、電極群２を電池外装体３に収容する第３の工程と、電解液を電池外装体３に注液する第４の工程と、を備える。 Then, the manufacturing method of the nonaqueous electrolyte secondary battery 1 is demonstrated. The manufacturing method of the nonaqueous electrolyte secondary battery 1 includes a first step of obtaining the positive electrode 6, a second step of obtaining the negative electrode 8, a third step of housing the electrode group 2 in the battery outer package 3, And a fourth step of injecting the electrolytic solution into the battery outer package 3.
　第１の工程では、正極合剤層１０に用いる材料を混練機、分散機等を用いて分散媒に分散させてスラリー状の正極合剤を得た後、この正極合剤をドクターブレード法、ディッピング法、スプレー法等により正極集電体９上に塗布し、その後分散媒を揮発させることにより正極６を得る。分散媒を揮発させた後、必要に応じて、ロールプレスによる圧縮成型工程が設けられてもよい。正極合剤層１０は、上述した正極合剤の塗布から分散媒の揮発までの工程を複数回行うことにより、多層構造の正極合剤層として形成されてもよい。分散媒は、水、１－メチル－２－ピロリドン（以下、ＮＭＰともいう。）等であってよい。 In the first step, after the material used for the positive electrode mixture layer 10 is dispersed in a dispersion medium using a kneader, a disperser or the like to obtain a slurry-like positive electrode mixture, the positive electrode mixture is treated with a doctor blade method, The positive electrode 6 is obtained by coating on the positive electrode current collector 9 by a dipping method, a spray method or the like, and then volatilizing the dispersion medium. After volatilizing the dispersion medium, a compression molding step using a roll press may be provided as necessary. The positive electrode mixture layer 10 may be formed as a positive electrode mixture layer having a multilayer structure by performing the above-described steps from application of the positive electrode mixture to volatilization of the dispersion medium a plurality of times. The dispersion medium may be water, 1-methyl-2-pyrrolidone (hereinafter also referred to as NMP), and the like.
　第２の工程は、上述した第１の工程と同様であってよく、負極集電体１１に負極合剤層１２を形成する方法は、上述した第１の工程と同様の方法であってよい。 The second step may be the same as the first step described above, and the method of forming the negative electrode mixture layer 12 on the negative electrode current collector 11 may be the same method as the first step described above. .
　第３の工程では、作製した正極６及び負極８の間にセパレータ７を挟み、電極群２を形成する。次いで、この電極群２を電池外装体３に収容する。 In the third step, the separator 7 is sandwiched between the produced positive electrode 6 and negative electrode 8, and the electrode group 2 is formed. Next, the electrode group 2 is accommodated in the battery outer package 3.
　第４の工程では、電解液を電池外装体３に注入する。電解液は、例えば、電解質塩をはじめに溶媒に溶解させてから、その他の材料を溶解させることにより調製することができる。 In the fourth step, the electrolytic solution is injected into the battery outer package 3. The electrolytic solution can be prepared, for example, by first dissolving the electrolyte salt in a solvent and then dissolving other materials.
　他の実施形態として、電気化学デバイスはキャパシタであってもよい。キャパシタは、上述した非水電解液二次電池１と同様に、正極、負極及びセパレータから構成される電極群と、電極群を収容する袋状の電池外装体とを備えていてよい。キャパシタにおける各構成要素の詳細は、非水電解液二次電池１と同様であってよい。 As another embodiment, the electrochemical device may be a capacitor. Similar to the non-aqueous electrolyte secondary battery 1 described above, the capacitor may include an electrode group including a positive electrode, a negative electrode, and a separator, and a bag-shaped battery outer package that houses the electrode group. The details of each component in the capacitor may be the same as those of the non-aqueous electrolyte secondary battery 1.
　以下、実施例により本発明を具体的に説明するが、本発明はこれらの実施例に限定されるものではない。 Hereinafter, the present invention will be specifically described by way of examples, but the present invention is not limited to these examples.
（実施例１）
［正極の作製］
　正極活物質としてのコバルト酸リチウム（９５質量％）に、導電剤としての繊維状の黒鉛（１質量％）及びアセチレンブラック（ＡＢ）（１質量％）と、結着剤（３質量％）とを順次添加し、混合した。得られた混合物に対し、分散媒としてのＮＭＰを添加し、混練することによりスラリー状の正極合剤を調製した。この正極合剤を正極集電体としての厚さ２０μｍのアルミニウム箔に均等且つ均質に所定量塗布した。その後、分散媒を揮発させてから、プレスすることにより密度３．６ｇ／ｃｍ３まで圧密化して、正極を得た。 Example 1
[Production of positive electrode]
Lithium cobaltate (95% by mass) as a positive electrode active material, fibrous graphite (1% by mass) and acetylene black (AB) (1% by mass) as a conductive agent, and a binder (3% by mass) Were added sequentially and mixed. To the obtained mixture, NMP as a dispersion medium was added and kneaded to prepare a slurry-like positive electrode mixture. A predetermined amount of this positive electrode mixture was uniformly and uniformly applied to an aluminum foil having a thickness of 20 μm as a positive electrode current collector. Then, after volatilizing the dispersion medium, the dispersion medium was compacted to a density of 3.6 g / cm 3 by pressing to obtain a positive electrode.
［負極の作製］
　負極活物質としての黒鉛に、結着剤と、増粘剤としてのカルボキシメチルセルロースとを添加した。これらの質量比については、負極活物質：結着剤：増粘剤＝９８：１：１とした。得られた混合物に対し、分散媒としての水を添加し、混練することによりスラリー状の負極合剤を調製した。この負極合剤を負極集電体としての厚さ１０μｍの圧延銅箔に均等且つ均質に所定量塗布した。その後、分散媒を揮発させてから、プレスすることにより密度１．６ｇ／ｃｍ３まで圧密化して、負極を得た。 [Production of negative electrode]
A binder and carboxymethylcellulose as a thickener were added to graphite as the negative electrode active material. About these mass ratios, it was set as negative electrode active material: binder: thickener = 98: 1: 1. To the obtained mixture, water as a dispersion medium was added and kneaded to prepare a slurry-like negative electrode mixture. A predetermined amount of this negative electrode mixture was uniformly and uniformly applied to a rolled copper foil having a thickness of 10 μm as a negative electrode current collector. Thereafter, the dispersion medium was volatilized and then pressed to a density of 1.6 g / cm 3 to obtain a negative electrode.
［リチウムイオン二次電池の作製］
　１３．５ｃｍ２の四角形に切断した正極電極を、セパレータであるポリエチレン製多孔質シート（商品名：ハイポア（登録商標）、旭化成株式会社製、厚さ３０μｍ）で挟み、さらに１４．３ｃｍ２の四角形に切断した負極を重ね合わせて電極群を作製した。この電極群を、アルミニウム製のラミネートフィルム（商品名：アルミラミネートフィルム、大日本印刷株式会社製）で形成された容器（電池外装体）に収容した。次いで、容器の中に電解液を１ｍＬ添加し、容器を熱溶着させ、評価用のリチウムイオン二次電池を作製した。電解液としては、１ｍｏｌ／ＬのＬｉＰＦ６を含むエチレンカーボネート、ジメチルカーボネート及びジエチルカーボネートの混合溶液に、混合溶液全量に対してビニレンカーボネート（ＶＣ）を１質量％と、下記式（５）で表される化合物Ａを１質量％（電解液全量基準）添加したものを使用した。
Figure JPOXMLDOC01-appb-C000013
 [Production of lithium ion secondary battery]
The positive electrode cut into a 13.5 cm 2 square is sandwiched between polyethylene porous sheets (trade name: Hypore (registered trademark), manufactured by Asahi Kasei Co., Ltd., thickness 30 μm) as a separator, and further a 14.3 cm 2 square. The electrode group was fabricated by stacking the negative electrodes cut into pieces. This electrode group was accommodated in a container (battery exterior body) formed of an aluminum laminate film (trade name: aluminum laminate film, manufactured by Dai Nippon Printing Co., Ltd.). Subsequently, 1 mL of electrolyte solution was added in the container, the container was heat-welded, and the lithium ion secondary battery for evaluation was produced. As the electrolytic solution, 1% by mass of vinylene carbonate (VC) with respect to the total amount of the mixed solution in a mixed solution of ethylene carbonate, dimethyl carbonate and diethyl carbonate containing 1 mol / L LiPF 6 is represented by the following formula (5). The compound A to which 1% by mass (based on the total amount of the electrolytic solution) was added was used.
Figure JPOXMLDOC01-appb-C000013
（比較例１）
　実施例１において、化合物Ａを使用しなかった以外は、実施例１と同様にしてリチウムイオン二次電池を作製した。 (Comparative Example 1)
In Example 1, a lithium ion secondary battery was produced in the same manner as in Example 1 except that Compound A was not used.
［初回充放電］
　作製したリチウムイオン電池について、以下に示す方法で初回充放電を実施した。まず、２５℃の環境下において０．１Ｃの電流値で定電流充電を上限電圧４．２Ｖまで行い、続いて４．２Ｖで定電圧充電を行った。充電終止条件は、電流値０．０１Ｃとした。その後、０．１Ｃの電流値で終止電圧２．５Ｖの定電流放電を行った。この充放電サイクルを３回繰り返した（電流値の単位として用いた「Ｃ」とは、「電流値（Ａ）／電池容量（Ａｈ）」を意味する。）。 [First charge / discharge]
About the produced lithium ion battery, initial charging / discharging was implemented by the method shown below. First, constant current charging was performed up to an upper limit voltage of 4.2 V at a current value of 0.1 C under an environment of 25 ° C., and then constant voltage charging was performed at 4.2 V. The charge termination condition was a current value of 0.01C. Thereafter, constant current discharge with a final voltage of 2.5 V was performed at a current value of 0.1 C. This charge / discharge cycle was repeated three times ("C" used as a unit of current value means "current value (A) / battery capacity (Ah)").
［サイクル特性の評価］
　初回充放電後に、充放電を繰り返すサイクル試験によって、実施例１及び比較例１の各二次電池のサイクル特性を評価した。充電パターンとしては、４５℃の環境下で、実施例１及び比較例１の二次電池を０．５Ｃの電流値で定電流充電を上限電圧４．２Ｖまで行い、続いて４．２Ｖで定電圧充電を行った。充電終止条件は、電流値０．０５Ｃとした。放電については、１Ｃで定電流放電を２．５Ｖまで行い、放電容量を求めた。この一連の充放電を３００サイクル繰返し、充放電の度に放電容量を測定した。比較例１における１サイクル目の充放電後の放電容量を１として、実施例１及び比較例１における各サイクルでの放電容量の相対値を求めた。サイクル数と放電容量の相対値との関係を、図３に示す。 [Evaluation of cycle characteristics]
The cycle characteristics of the secondary batteries of Example 1 and Comparative Example 1 were evaluated by a cycle test in which charging / discharging was repeated after the first charge / discharge. As a charging pattern, in the environment of 45 ° C., the secondary batteries of Example 1 and Comparative Example 1 were charged with a constant current at a current value of 0.5 C up to an upper limit voltage of 4.2 V, and then fixed at 4.2 V. Voltage charging was performed. The charge termination condition was a current value of 0.05C. About discharge, constant current discharge was performed to 2.5V at 1C, and the discharge capacity was obtained. This series of charge and discharge was repeated for 300 cycles, and the discharge capacity was measured each time the charge and discharge were performed. Assuming that the discharge capacity after charge / discharge in the first cycle in Comparative Example 1 was 1, the relative value of the discharge capacity in each cycle in Example 1 and Comparative Example 1 was determined. FIG. 3 shows the relationship between the number of cycles and the relative value of the discharge capacity.
　（実施例２）
　実施例１において、負極活物質として更にケイ素酸化物を加え、負極を作製した以外は実施例１と同様にして、リチウムイオン二次電池を作製した。負極における負極活物質、結着剤及び増粘剤の質量比は、黒鉛：ケイ素酸化物：結着剤：増粘剤＝９２：５：１．５：１．５とした。 (Example 2)
A lithium ion secondary battery was produced in the same manner as in Example 1 except that silicon oxide was further added as the negative electrode active material in Example 1 to produce a negative electrode. The mass ratio of the negative electrode active material, the binder and the thickener in the negative electrode was graphite: silicon oxide: binder: thickener = 92: 5: 1.5: 1.5.
（実施例３～５）
　実施例２において、化合物Ａの含有量を、電解液全量基準で、それぞれ０．１質量％（実施例３）、０．５質量％（実施例４）及び３質量％（実施例５）に変更した以外は、実施例１と同様にしてリチウムイオン二次電池を作製した。 (Examples 3 to 5)
In Example 2, the content of Compound A is 0.1% by mass (Example 3), 0.5% by mass (Example 4), and 3% by mass (Example 5), respectively, based on the total amount of the electrolytic solution. A lithium ion secondary battery was produced in the same manner as in Example 1 except for the change.
（比較例２）
　実施例２において、化合物Ａを使用しなかった以外は、実施例２と同様にしてリチウムイオン二次電池を作製した。 (Comparative Example 2)
A lithium ion secondary battery was produced in the same manner as in Example 2 except that Compound A was not used in Example 2.
（比較例３）
　実施例２において、化合物Ａに代えて、４－フルオロ－１，３－ジオキソラン－２－オン（フルオロエチレンカーボネート；ＦＥＣ)を電解液全量基準で１質量％添加したこと以外は、実施例２と同様にしてリチウムイオン二次電池を作製した。 (Comparative Example 3)
In Example 2, instead of Compound A, 4-fluoro-1,3-dioxolan-2-one (fluoroethylene carbonate; FEC) was added in an amount of 1% by mass based on the total amount of the electrolyte solution. Similarly, a lithium ion secondary battery was produced.
［初回充放電］
　実施例１及び比較例１における評価と同様の方法により、実施例２～５及び比較例２～３の各二次電池の初回充放電を実施した。 [First charge / discharge]
The secondary batteries of Examples 2 to 5 and Comparative Examples 2 to 3 were charged and discharged for the first time by the same method as the evaluation in Example 1 and Comparative Example 1.
　［サイクル特性の評価］
　実施例１及び比較例１における評価方法と同様の方法により、実施例２～５及び比較例２～３の各二次電池のサイクル特性を評価した。比較例２における１サイクル目の充放電後の放電容量を１として、実施例２～５及び比較例３における各サイクルでの放電容量の相対値を求めた。サイクル数と放電容量の相対値との関係を、図４に示す。 [Evaluation of cycle characteristics]
The cycle characteristics of the secondary batteries of Examples 2 to 5 and Comparative Examples 2 to 3 were evaluated by the same method as the evaluation method in Example 1 and Comparative Example 1. The discharge capacity after charge / discharge in the first cycle in Comparative Example 2 was taken as 1, and the relative value of the discharge capacity in each cycle in Examples 2 to 5 and Comparative Example 3 was determined. FIG. 4 shows the relationship between the number of cycles and the relative value of the discharge capacity.
　図３に示すように、負極活物質として黒鉛を用い、更に化合物Ａを１質量％含む電解液を適用した実施例１のリチウムイオン二次電池は、化合物Ａを含まない電解液を適用した比較例１のリチウムイオン二次電池と比較して、サイクル特性の評価が良好であった。図４に示すように、黒鉛及びケイ素酸化物を含む負極活物質を用い、更に化合物Ａを１質量％、０．１質量％、０．５質量％、３質量％含む電解液を適用した実施例２～５のリチウムイオン二次電池は、化合物Ａを含まない電解液を適用した比較例２及び比較例３のリチウムイオン二次電池と比較して、サイクル特性の評価が良好であった。このメカニズムは必ずしも明らかではないが、化合物Ａが正極又は負極上で安定な被膜を形成したために、電解液の分解物が正極又は負極上に堆積することに起因する出力特性の低下を抑制できたと考えられる。さらに、その安定な被膜形成によって、電極近傍での電解質の分解等の副反応及びリチウムイオン二次電池の容量低下が抑制され、それらの効果によって、サイクル特性が向上したと考えられる。 As shown in FIG. 3, the lithium ion secondary battery of Example 1 using graphite as the negative electrode active material and further applying an electrolytic solution containing 1% by mass of compound A is a comparison in which an electrolytic solution not containing compound A is applied. Compared with the lithium ion secondary battery of Example 1, the evaluation of the cycle characteristics was good. As shown in FIG. 4, an implementation in which an anode active material containing graphite and silicon oxide was used, and an electrolytic solution containing 1% by mass, 0.1% by mass, 0.5% by mass, and 3% by mass of Compound A was applied. The lithium ion secondary batteries of Examples 2 to 5 had better evaluation of cycle characteristics than the lithium ion secondary batteries of Comparative Example 2 and Comparative Example 3 to which the electrolyte solution containing no compound A was applied. Although this mechanism is not necessarily clear, since the compound A formed a stable film on the positive electrode or the negative electrode, it was possible to suppress a decrease in output characteristics due to the decomposition product of the electrolyte depositing on the positive electrode or the negative electrode. Conceivable. Further, the stable film formation suppresses side reactions such as electrolyte decomposition in the vicinity of the electrode and a decrease in capacity of the lithium ion secondary battery, and it is considered that the cycle characteristics are improved by these effects.
　１…非水電解液二次電池（電気化学デバイス）、６…正極、７…セパレータ、８…負極。 1 ... non-aqueous electrolyte secondary battery (electrochemical device), 6 ... positive electrode, 7 ... separator, 8 ... negative electrode.

Claims (9)

  1. 　下記式（１）で表される化合物を含有する、電解液。
    Figure JPOXMLDOC01-appb-C000001
     ［式（１）中、Ｒ１～Ｒ３は、それぞれ独立に、アルキル基又はフッ素原子を示し、Ｒ４はアルキレン基を示し、Ｒ５は、硫黄原子を含む有機基を示す。］     An electrolytic solution containing a compound represented by the following formula (1).
    Figure JPOXMLDOC01-appb-C000001
     [In Formula (1), R 1 to R 3 each independently represents an alkyl group or a fluorine atom, R 4 represents an alkylene group, and R 5 represents an organic group containing a sulfur atom. ]
  2. 　前記Ｒ５は、下記式（２）、式（３）又は式（４）のいずれかで表される基である、請求項１に記載の電解液。
    Figure JPOXMLDOC01-appb-C000002
     ［式（２）中、Ｒ６はアルキル基を示し、＊は結合手を示す。］
    Figure JPOXMLDOC01-appb-C000003
     ［式（３）中、Ｒ７はアルキル基を示し、＊は結合手を示す。］
    Figure JPOXMLDOC01-appb-C000004
     ［式（３）中、Ｒ８はアルキル基を示し、＊は結合手を示す。］     2. The electrolytic solution according to claim 1, wherein R 5 is a group represented by any of the following formula (2), formula (3), or formula (4).
    Figure JPOXMLDOC01-appb-C000002
     [In formula (2), R 6 represents an alkyl group, and * represents a bond. ]
    Figure JPOXMLDOC01-appb-C000003
     [In formula (3), R 7 represents an alkyl group, and * represents a bond. ]
    Figure JPOXMLDOC01-appb-C000004
     [In formula (3), R 8 represents an alkyl group, and * represents a bond. ]
  3. 　前記Ｒ１～Ｒ３の少なくとも１つはフッ素原子である、請求項１又は２に記載の電解液。 The electrolytic solution according to claim 1, wherein at least one of R 1 to R 3 is a fluorine atom.
  4. 　前記式（１）で表される化合物の含有量は、前記電解液全量を基準として１０質量％以下である、請求項１～３のいずれか一項に記載の電解液。 The electrolyte solution according to any one of claims 1 to 3, wherein the content of the compound represented by the formula (1) is 10% by mass or less based on the total amount of the electrolyte solution.
  5. 　正極と、負極と、請求項１～４のいずれか一項に記載の電解液と、を備える電気化学デバイス。 An electrochemical device comprising: a positive electrode; a negative electrode; and the electrolytic solution according to any one of claims 1 to 4.
  6. 　前記負極は炭素材料を含有する、請求項５に記載の電気化学デバイス。 The electrochemical device according to claim 5, wherein the negative electrode contains a carbon material.
  7. 　前記炭素材料は黒鉛を含有する、請求項６に記載の電気化学デバイス。 The electrochemical device according to claim 6, wherein the carbon material contains graphite.
  8. 　前記負極は、ケイ素及びスズからなる群の少なくとも１種の元素を含む材料を更に含有する、請求項６又は７に記載の電気化学デバイス。 The electrochemical device according to claim 6 or 7, wherein the negative electrode further contains a material containing at least one element of the group consisting of silicon and tin.
  9. 　前記電気化学デバイスは、非水電解液二次電池又はキャパシタである、請求項５～８のいずれか一項に記載の電気化学デバイス。 The electrochemical device according to any one of claims 5 to 8, wherein the electrochemical device is a nonaqueous electrolyte secondary battery or a capacitor.
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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2016006488A1 (en) * 2014-07-07 2016-01-14 株式会社Adeka Nonaqueous electrolyte for capacitor, and capacitor
WO2016054493A1 (en) * 2014-10-02 2016-04-07 Silatronix, Inc. Organosilicon-containing electrolyte compositions having enhanced electrochemical and thermal stability
WO2016054621A1 (en) * 2014-10-03 2016-04-07 Silatronix, Inc. Functionalized silanes and electrolyte compositions and electrochemical devices containing them
JP2016126855A (en) * 2014-12-26 2016-07-11 三星エスディアイ株式会社Samsung SDI Co., Ltd. Lithium ion secondary battery
JP2016520647A (en) * 2013-06-04 2016-07-14 シラトロニクス，インコーポレイテッド Nitrile-substituted silanes and electrolyte compositions and electrochemical devices containing them

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2016520647A (en) * 2013-06-04 2016-07-14 シラトロニクス，インコーポレイテッド Nitrile-substituted silanes and electrolyte compositions and electrochemical devices containing them
WO2016006488A1 (en) * 2014-07-07 2016-01-14 株式会社Adeka Nonaqueous electrolyte for capacitor, and capacitor
WO2016054493A1 (en) * 2014-10-02 2016-04-07 Silatronix, Inc. Organosilicon-containing electrolyte compositions having enhanced electrochemical and thermal stability
WO2016054621A1 (en) * 2014-10-03 2016-04-07 Silatronix, Inc. Functionalized silanes and electrolyte compositions and electrochemical devices containing them
JP2016126855A (en) * 2014-12-26 2016-07-11 三星エスディアイ株式会社Samsung SDI Co., Ltd. Lithium ion secondary battery

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