WO2018221676A1 - 電解液及び電気化学デバイス - Google Patents
電解液及び電気化学デバイス Download PDFInfo
- Publication number
- WO2018221676A1 WO2018221676A1 PCT/JP2018/021036 JP2018021036W WO2018221676A1 WO 2018221676 A1 WO2018221676 A1 WO 2018221676A1 JP 2018021036 W JP2018021036 W JP 2018021036W WO 2018221676 A1 WO2018221676 A1 WO 2018221676A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- mass
- negative electrode
- positive electrode
- secondary battery
- electrochemical device
- Prior art date
Links
Images
Classifications
-
- 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
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07F—ACYCLIC, CARBOCYCLIC OR HETEROCYCLIC COMPOUNDS CONTAINING ELEMENTS OTHER THAN CARBON, HYDROGEN, HALOGEN, OXYGEN, NITROGEN, SULFUR, SELENIUM OR TELLURIUM
- C07F7/00—Compounds containing elements of Groups 4 or 14 of the Periodic System
- C07F7/02—Silicon compounds
- C07F7/08—Compounds having one or more C—Si linkages
- C07F7/12—Organo silicon halides
-
- 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
- H01M10/052—Li-accumulators
- H01M10/0525—Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
-
- 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
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/36—Selection of substances as active materials, active masses, active liquids
- H01M4/38—Selection of substances as active materials, active masses, active liquids of elements or alloys
- H01M4/381—Alkaline or alkaline earth metals elements
- H01M4/382—Lithium
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/36—Selection of substances as active materials, active masses, active liquids
- H01M4/38—Selection of substances as active materials, active masses, active liquids of elements or alloys
- H01M4/386—Silicon or alloys based on silicon
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/36—Selection of substances as active materials, active masses, active liquids
- H01M4/38—Selection of substances as active materials, active masses, active liquids of elements or alloys
- H01M4/387—Tin or alloys based on tin
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/36—Selection of substances as active materials, active masses, active liquids
- H01M4/58—Selection of substances as active materials, active masses, active liquids of inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy; of polyanionic structures, e.g. phosphates, silicates or borates
- H01M4/583—Carbonaceous material, e.g. graphite-intercalation compounds or CFx
- H01M4/5835—Comprising fluorine or fluoride salts
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/36—Selection of substances as active materials, active masses, active liquids
- H01M4/58—Selection of substances as active materials, active masses, active liquids of inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy; of polyanionic structures, e.g. phosphates, silicates or borates
- H01M4/583—Carbonaceous material, e.g. graphite-intercalation compounds or CFx
- H01M4/587—Carbonaceous material, e.g. graphite-intercalation compounds or CFx for inserting or intercalating light metals
-
- 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
- H01G11/04—Hybrid capacitors
- H01G11/06—Hybrid capacitors with one of the electrodes allowing ions to be reversibly doped thereinto, e.g. lithium ion capacitors [LIC]
-
- 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
- H01M10/052—Li-accumulators
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M2300/00—Electrolytes
- H01M2300/0017—Non-aqueous electrolytes
- H01M2300/0025—Organic electrolyte
-
- 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
-
- 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
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T10/00—Road transport of goods or passengers
- Y02T10/60—Other road transportation technologies with climate change mitigation effect
- Y02T10/70—Energy storage systems for electromobility, e.g. 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 this invention is to provide the electrolyte solution which can reduce the resistance of an electrochemical device.
- Another object of the present invention is to provide an electrochemical device with reduced resistance.
- the present inventors have found that the resistance of an electrochemical device can be reduced by containing a specific compound containing a silicon atom and a nitrogen atom in an electrolytic solution.
- the charge capacity of electrochemical devices at low temperatures is lower than the charge capacity at normal temperatures (eg, 25 ° C.), but for electrochemical devices, the reduction in charge capacity is suppressed as much as possible. In other words, it is required to have excellent low-temperature input characteristics.
- the present inventors have also found that the low temperature input characteristics of an electrochemical device can be improved by including a specific compound containing a silicon atom and a nitrogen atom in the electrolytic solution.
- Patent Document 1 it is also important to improve the cycle characteristics of the electrochemical device. It is also important to improve the discharge rate characteristics of the electrochemical device. Furthermore, it is also required that the volume increase (expansion) of the electrochemical device with time is suppressed. It has also been found by the present inventors that these characteristics of an electrochemical device can be improved by including the compound in an electrolytic solution.
- This invention provides the electrolyte solution which contains the compound represented by following formula (1) as a 1st aspect, and whose content of this compound is 10 mass% or less on the basis of electrolyte solution whole quantity.
- 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 nitrogen atom.
- R 5 is preferably a group represented by the following formula (2).
- R 6 and R 7 each independently represent a hydrogen atom or an alkyl group, and * represents a bond. ]
- At least one of R 1 to R 3 is preferably a fluorine atom.
- 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 reducing the resistance of an electrochemical device can be provided.
- the electrochemical device with which resistance was reduced can be provided.
- an electrolytic solution that can improve low temperature input characteristics and / or cycle characteristics of an electrochemical device, and an electrochemical device excellent in low temperature input characteristics and / or cycle characteristics are provided. You can also
- FIG. 1 It is a perspective view which shows the nonaqueous electrolyte secondary battery as an electrochemical device which concerns on one Embodiment. It is a disassembled perspective view which shows the electrode group of the secondary battery shown in FIG. It is a graph which shows the measurement result of resistance of Example 1 and Comparative Example 1. 6 is a graph showing measurement results of resistances in Examples 2 to 4 and Comparative Examples 2 to 3. 4 is a graph showing evaluation results of cycle characteristics of Example 2 and Comparative Examples 2 to 3. 6 is a graph showing measurement results of resistances (upper limit voltage 4.2 V) in Examples 5 to 6 and Comparative Example 4; It is a graph which shows the measurement result of resistance (upper limit voltage 4.3V) of Example 5 and Comparative Example 4.
- 7 is a graph showing measurement results of resistances in Examples 7 to 8 and Comparative Example 5.
- 10 is a graph showing measurement results of resistances in Examples 9 to 10 and Comparative Example 6.
- 7 is a graph showing measurement results of resistances of Examples 11 to 12 and Comparative Example 7. It is a graph which shows the measurement result of resistance of Example 13 and Comparative Example 8. It is a graph which shows the evaluation result of the cycle characteristics of Example 14 and Comparative Example 8. It is a graph which shows the evaluation result of the discharge rate characteristic of Example 13 and Comparative Example 8.
- 10 is a graph showing measurement results of resistance in Example 15 and Comparative Examples 9 to 10.
- 10 is a graph showing measurement results of volume change amounts of Example 15 and Comparative Examples 9 to 10.
- 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.
- LiNi 0.8 Co 0.15 Al 0.05 O 2 There may be.
- the positive electrode active material may be, for example, lithium phosphate.
- the lithium phosphate include lithium manganese phosphate (LiMnPO 4 ), lithium iron phosphate (LiFePO 4 ), lithium cobalt phosphate (LiCoPO 4 ), and lithium vanadium phosphate (Li 3 V 2 (PO 4 ). 3 ).
- 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 not 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 materials carbon materials have high conductivity and are particularly excellent in low temperature characteristics and cycle stability.
- graphite is preferable from the viewpoint of increasing the capacity.
- the carbon network plane interlayer (d002) in the X-ray wide angle diffraction method is preferably less than 0.34 nm, more preferably 0.3354 nm or more and 0.337 nm or less.
- a carbon material that satisfies such conditions may be referred to as pseudo-anisotropic carbon.
- 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 8 preferably includes a carbon material, more preferably includes graphite, and more preferably includes a carbon material, silicon, and tin as the negative electrode active material. It includes a mixture with a material containing at least one element selected from the group, and particularly preferably includes a mixture of graphite and silicon oxide.
- the content of the carbon material (graphite) relative to 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 based on the total amount of the mixture, or 3 It may be not less than mass% and may be not more than 30 mass%.
- 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 contain a thickener in order to adjust the viscosity.
- the thickener is not particularly limited, and may be carboxymethylcellulose, methylcellulose, hydroxymethylcellulose, ethylcellulose, polyvinyl alcohol, oxidized starch, phosphorylated starch, casein, and salts thereof.
- 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 positive 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 nitrogen 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 from the viewpoint of further reducing the resistance of the electrochemical device and further improving the low temperature input characteristics.
- R 6 and R 7 each independently represent a hydrogen atom or an alkyl group.
- the alkyl group represented by R 6 or R 7 may be the same as the alkyl group represented by R 1 to R 3 described above. * Indicates a bond.
- the number of silicon atoms in one molecule of the compound represented by formula (1) is one. That is, in one embodiment, the organic group represented by R 5 does not contain a silicon atom.
- the content of the compound represented by the formula (1) is preferably 0.001% by mass or more based on the total amount of the electrolyte from the viewpoint of further reducing the resistance of the electrochemical device and further improving the low temperature input characteristics. Yes, more preferably 0.005% by mass or more, and still more preferably 0.01% by mass or more. From the same viewpoint, the content of the compound represented by the formula (1) is preferably 10% by mass or less, 7% by mass or less, 5% by mass or less, 3% by mass or less, based on the total amount of the electrolytic solution. It is less than mass%, less than 1.5 mass%, or less than 1 mass%.
- the content of the compound represented by the formula (1) is preferably 0.001 to 10% by mass, 0.001 to 0.001% based on the total amount of the electrolyte from the viewpoint of further improving the low temperature input characteristics of the electrochemical device. 7% by mass, 0.001 to 5% by mass, 0.001 to 3% by mass, 0.001 to 2% by mass, 0.001 to 1.5% by mass, 0.001 to 1% by mass, 0.005 to 10% by mass, 0.005 to 7% by mass, 0.005 to 5% by mass, 0.005 to 3% by mass, 0.005 to 2% by mass, 0.005 to 1.5% by mass, 0.005 to 1% by mass, 0.01-10% by mass, 0.01-7% by mass, 0.01-5% by mass, 0.01-3% by mass, 0.01-2% by mass, 0.01-1. 5% by mass, or 0.01 to 1% by mass.
- 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 ) and at least one selected from the group consisting of 2 Good.
- the lithium salt preferably contains LiPF 6 from the viewpoint of further excellent 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 or less, 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 remarkably improved low-temperature input characteristics by applying the compound represented by the above formula (1) to the electrolytic solution. , Revealed that the resistance was reduced.
- the present inventors infer the effects of using the compound represented by the formula (1) in the 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 in the low temperature resulting from the decomposition product of electrolyte solution depositing on a positive electrode or a negative electrode is suppressed. Furthermore, a decrease in capacity and an increase in resistance at low temperatures due to the decomposition of the electrolyte salt are suppressed.
- the low temperature input characteristics of the non-aqueous 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.
- 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 (3).
- a compound A to which 1% by mass (based on the total amount of electrolytic solution) was added based on the total amount of the electrolytic solution 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.
- the charging capacity at the time of charging was defined as a charging capacity C2 at a low temperature ( ⁇ 10 ° C.).
- the low temperature input characteristic was computed with the following formula
- Low temperature input characteristics (%) C2 / C1 ⁇ 100
- 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 3 the content of Compound A was changed to 0.5% by mass (Example 3) and 0.1% by mass (Example 4), respectively, based on the total amount of the electrolyte solution. Similarly, a lithium ion secondary battery was produced.
- 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
- FIG. 5 shows the relationship between the number of cycles and the relative value of the discharge capacity.
- the lithium ion secondary battery of Example 1 to which graphite was used as the negative electrode active material and an electrolytic solution containing 1% by mass of compound A was applied was an electrolyte containing no compound A.
- the resistance was reduced and the input characteristics at a low temperature ( ⁇ 10 ° C.) were good.
- Examples 2 to 4 in which an anode active material containing graphite and silicon oxide was used and an electrolyte containing 1, 0.5, and 0.1% by mass of Compound A were applied.
- the lithium ion secondary battery of Example 2 using a negative electrode active material containing graphite and silicon oxide and further applying an electrolytic solution containing 1% by mass of compound A is a comparison not containing compound A.
- the cycle characteristics were good as compared with the lithium ion secondary batteries of Examples 2 to 3.
- the improvement mechanism of this cycle characteristic is not necessarily clear, the addition of Compound A formed a film having better ion conductivity than the film formed by the influence of FEC on the positive electrode or the negative electrode, This is considered to be due to the suppression of the decomposition of the electrolytic solution accompanying this, and further to the stabilization of the lithium salt (LIPF 6 ).
- Example 5 Lithium nickel cobalt manganate (LiNi 1/3 Co 1/3 Mn 1/3 O 2 , 91% by mass) as a positive electrode active material, acetylene black (AB) (5% by mass) as a conductive agent, and a binder (4% by mass) were sequentially added 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 ⁇ m as a positive electrode current collector. Then, after volatilizing the dispersion medium, the dispersion medium was compacted to a density of 2.8 g / cm 3 by pressing to obtain a positive electrode.
- Lithium nickel cobalt manganate LiNi 1/3 Co 1/3 Mn 1/3 O 2 , 91% by mass
- AB acetylene black
- a binder 4% by mass
- a negative electrode was obtained in the same manner as in Example 1 except that the density at the time of consolidation was changed to 1.2 g / cm 3 .
- a lithium ion secondary battery for evaluation was produced in the same manner as in Example 1.
- As an 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 of LiPF 6 and 0.1% of the above-described compound A were added. What added 2 mass% (electrolyte whole quantity basis) was used.
- Example 6 a lithium ion secondary battery was produced in the same manner as in Example 5 except that the content of Compound A was changed to 0.5% by mass based on the total amount of the electrolytic solution.
- Example 5 (Comparative Example 4) In Example 5, a lithium ion secondary battery was produced in the same manner as in Example 5 except that Compound A was not used.
- Example 7 lithium ion was added in the same manner as in Example 5 except that silicon oxide was further added as the negative electrode active material, and the density during consolidation was changed to 1.6 g / cm 3 to produce the negative electrode. A secondary battery was produced.
- Example 7 a lithium ion secondary battery was produced in the same manner as in Example 7 except that the content of Compound A was changed to 0.5% by mass based on the total amount of the electrolyte solution.
- Example 7 (Comparative Example 5) In Example 7, a lithium ion secondary battery was produced in the same manner as in Example 7 except that Compound A was not used.
- Example 9 In Example 5, a lithium ion secondary battery was produced in the same manner as in Example 5, except that lithium cobalt cobalt manganate (LiNi 0.5 Co 0.2 Mn 0.3 O 2 ) was used as the positive electrode active material. did.
- lithium cobalt cobalt manganate LiNi 0.5 Co 0.2 Mn 0.3 O 2
- Example 10 a lithium ion secondary battery was produced in the same manner as in Example 9, except that the content of Compound A was changed to 0.5% by mass based on the total amount of the electrolyte solution.
- Example 9 a lithium ion secondary battery was produced in the same manner as in Example 9 except that Compound A was not used.
- Example 11 In Example 5, lithium iron phosphate (90% by mass) was used as the positive electrode active material, the binder content was changed to 5% by mass, and the density at the time of consolidation was changed to 2.0 g / cm 3 . A lithium ion secondary battery was produced in the same manner as in Example 5 except that the positive electrode was produced.
- Example 12 a lithium ion secondary battery was produced in the same manner as in Example 11 except that the content of Compound A was changed to 0.5% by mass based on the total amount of the electrolytic solution.
- Example 7 a lithium ion secondary battery was produced in the same manner as in Example 11 except that Compound A was not used.
- Example 13 [Production of positive electrode] Lithium nickel cobalt manganate (LiNi 0.6 Co 0.2 Mn 0.2 O 2 , 91% by mass) as a positive electrode active material, acetylene black (AB) (5% by mass) as a conductive agent, and a binder (4% by mass) were sequentially added 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 ⁇ m as a positive electrode current collector. Then, after volatilizing the dispersion medium, the dispersion medium was compacted to a density of 2.8 g / cm 3 by pressing to obtain a positive electrode.
- Lithium nickel cobalt manganate LiNi 0.6 Co 0.2 Mn 0.2 O 2 , 91% by mass
- AB acetylene black
- a binder
- a negative electrode was obtained in the same manner as in Example 1.
- a lithium ion secondary battery for evaluation was produced in the same manner as in Example 1.
- As an 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 of LiPF 6 and 0.1% of the above-described compound A were added. What added 5 mass% (electrolyte whole quantity basis) was used.
- Example 14 a lithium ion secondary battery was produced in the same manner as in Example 13 except that the content of Compound A was changed to 0.2% by mass based on the total amount of the electrolyte.
- Example 13 a lithium ion secondary battery was produced in the same manner as in Example 13 except that Compound A was not used.
- Discharge capacity retention rate (%) (discharge capacity at current values 0.2C, 0.5C, 1C, 2C / discharge capacity at current value 0.2C) ⁇ 100
- Example 15 [Production of positive electrode] Acetylene black (AB) (3 mass%) and a binder (2 mass%) as a conductive agent were sequentially added to and mixed with lithium nickel cobalt aluminum oxide (95 mass%) as the positive electrode active material. 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 ⁇ m as a positive electrode current collector. Thereafter, the dispersion medium from evaporating, and compacted to a density 3.0 g / cm 3 by pressing to obtain a positive electrode.
- a negative electrode was obtained in the same manner as in Example 1.
- a lithium ion secondary battery for evaluation was produced in the same manner as in Example 1.
- As an 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 of LiPF 6 and 0.1% of the above-described compound A were added. What added 1 mass% (electrolyte whole quantity basis) was used.
- Example 15 a lithium ion secondary battery was produced in the same manner as in Example 13 except that Compound A was not used.
- Example 15 a lithium ion secondary battery was produced in the same manner as in Example 15 except that instead of Compound A, 0.5 mass% of FEC was added based on the total amount of the electrolytic solution.
- Example 15 and Comparative Examples 9 to 10 were stored at 80 ° C. for 7 days.
- the volume of the secondary battery is measured every day with an electronic hydrometer based on the Archimedes method (electronic hydrometer MDS-300, manufactured by Alpha Mirage), and the difference from the volume of the secondary battery before storage (day 0) is measured. I asked for each. The results are shown in FIG.
- non-aqueous electrolyte secondary battery electrochemical device
- 6 positive electrode
- 7 separator
- 8 negative electrode
Abstract
Description
[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。
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。
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(3)で表される化合物Aを電解液全量基準で1質量%(電解液全量基準)添加したものを使用した。
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。
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。)。
初回充放電後に、実施例1及び比較例1のリチウムイオン二次電池の抵抗を交流インピーダンス測定にて評価した。作製したリチウムイオン電池を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。それらのリチウムイオン二次電池について、25℃の環境下で、10mVの振幅で20mHz~200kHzの周波数範囲で交流インピーダンス測定装置(1260型、Solartron社製)を用いて抵抗を測定した。測定結果を図3に示す。
初回充放電後に、実施例1及び比較例1の各二次電池の低温入力特性を評価した。具体的には、まず、25℃の環境下で0.1Cの定電流充電を上限電圧4.2Vまで行った。この充電時の容量を25℃での充電容量C1とした。次に、25℃の環境下で0.1Cの電流値で終止電圧2.5Vの定電流放電を行った。その後、-10℃の環境下に1時間保持した後、―10℃のまま0.1Cの定電流充電を上限電圧4.2Vまで行った。この充電時の充電容量を低温(-10℃)での充電容量C2とした。そして、以下の式により低温入力特性を算出した。結果を表1に示す。
低温入力特性(%)=C2/C1×100
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。
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0.5質量%(実施例3)及び0.1質量%(実施例4)に変更した以外は、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。
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。
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。
実施例1及び比較例1における方法と同様の方法により、実施例2~4及び比較例2~3の各二次電池の初回充放電を実施した。
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2~4及び比較例2~3の各二次電池の抵抗を測定した。結果を図4に示す。
初回充放電後、充放電を繰り返すサイクル試験によって、実施例2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。充電パターンとしては、45℃の環境下で、実施例2及び比較例2~3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200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(放電容量比率)を求めた。サイクル数と放電容量の相対値との関係を、図5に示す。
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2~4及び比較例2の各二次電池の低温入力特性を評価した。結果を表2に示す。
[正極の作製]
正極活物質としてのニッケルコバルトマンガン酸リチウム(LiNi1/3Co1/3Mn1/3O2、91質量%)に、導電剤としてアセチレンブラック(AB)(5質量%)と、結着剤(4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2.8g/cm3まで圧密化して、正極を得た。
圧密化する際の密度を1.2g/cm3に変更した以外は、実施例1と同様の方法により負極を得た。
実施例1と同様の方法により、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、上述した化合物Aを0.2質量%(電解液全量基準)添加したものを使用した。
実施例5において、化合物Aの含有量を、電解液全量基準で0.5質量%に変更した以外は、実施例5と同様にしてリチウムイオン二次電池を作製した。
実施例5において、化合物Aを使用しなかった以外は、実施例5と同様にしてリチウムイオン二次電池を作製した。
定電流放電の終止電圧を2.7Vとした以外は、実施例1及び比較例1における方法と同様の方法により、実施例5~6及び比較例4の各二次電池の初回充放電を実施した。
初回充放電後に、実施例5~6及び比較例4のリチウムイオン二次電池の抵抗を交流インピーダンス測定にて評価した。作製したリチウムイオン電池を25℃の環境下において0.2C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。それらのリチウムイオン二次電池について、25℃の環境下で、10mVの振幅で20mHz~200kHzの周波数範囲で交流インピーダンス測定装置(VSP、Bio-Logic社)を用いて、抵抗を測定した。測定結果を図6に示す。
実施例5及び比較例4の各二次電池について、上限電圧を4.3Vとした以外は、上限電圧を4.2Vとしたときの方法と同様の方法により各二次電池の抵抗を測定した。測定結果を図7に示す。
実施例5において、負極活物質として更にケイ素酸化物を加え、圧密化する際の密度を1.6g/cm3に変更して負極を作製した以外は、実施例5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。
実施例7において、化合物Aの含有量を、電解液全量基準で0.5質量%に変更した以外は、実施例7と同様にしてリチウムイオン二次電池を作製した。
実施例7において、化合物Aを使用しなかった以外は、実施例7と同様にしてリチウムイオン二次電池を作製した。
実施例5~6及び比較例4における方法と同様の方法により、実施例7~8及び比較例5の各二次電池の初回充放電を実施した。
実施例7~8及び比較例5の各二次電池について、実施例5~6及び比較例4における方法(上限電圧を4.2Vとしたときの方法)と同様の方法により各二次電池の抵抗を測定した。測定結果を図8に示す。
実施例5において、正極活物質としてニッケルコバルトマンガン酸リチウム(LiNi0.5Co0.2Mn0.3O2)を使用した以外は、実施例5と同様にしてリチウムイオン二次電池を作製した。
実施例9において、化合物Aの含有量を、電解液全量基準で0.5質量%に変更した以外は、実施例9と同様にしてリチウムイオン二次電池を作製した。
実施例9において、化合物Aを使用しなかった以外は、実施例9と同様にしてリチウムイオン二次電池を作製した。
実施例5~6及び比較例4における方法と同様の方法により、実施例9~10及び比較例6の各二次電池の初回充放電を実施した。
実施例9~10及び比較例6の各二次電池について、実施例5~6及び比較例4における方法(上限電圧を4.2Vとしたときの方法)と同様の方法により各二次電池の抵抗を測定した。測定結果を図9に示す。
実施例5において、正極活物質としてリン酸鉄リチウム(90質量%)を用い、結着剤の含有量を5質量%に変更し、圧密化する際の密度を2.0g/cm3に変更して正極を作製した以外は、実施例5と同様にして、リチウムイオン二次電池を作製した。
実施例11において、化合物Aの含有量を、電解液全量基準で0.5質量%に変更した以外は、実施例11と同様にしてリチウムイオン二次電池を作製した。
実施例11において、化合物Aを使用しなかった以外は、実施例11と同様にしてリチウムイオン二次電池を作製した。
実施例5~6及び比較例4における方法と同様の方法により、実施例11~12及び比較例7の各二次電池の初回充放電を実施した。
実施例11~12及び比較例7の各二次電池について、実施例5~6及び比較例4における方法(上限電圧を4.2Vとしたときの方法)と同様の方法により各二次電池の抵抗を測定した。測定結果を図10に示す。
[正極の作製]
正極活物質としてのニッケルコバルトマンガン酸リチウム(LiNi0.6Co0.2Mn0.2O2、91質量%)に、導電剤としてアセチレンブラック(AB)(5質量%)と、結着剤(4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2.8g/cm3まで圧密化して、正極を得た。
実施例1と同様の方法により負極を得た。
実施例1と同様の方法により、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、上述した化合物Aを0.5質量%(電解液全量基準)添加したものを使用した。
実施例13において、化合物Aの含有量を、電解液全量基準で0.2質量%に変更した以外は、実施例13と同様にしてリチウムイオン二次電池を作製した。
実施例13において、化合物Aを使用しなかった以外は、実施例13と同様にしてリチウムイオン二次電池を作製した。
実施例5~6及び比較例4における方法と同様の方法により、実施例13~14及び比較例8の各二次電池の初回充放電を実施した。
実施例13及び比較例8の各二次電池について、実施例5~6及び比較例4における方法(上限電圧を4.2Vとしたときの方法)と同様の方法により各二次電池の抵抗を測定した。測定結果を図11に示す。
実施例14及び比較例8の各二次電池について、実施例2及び比較例2~3における評価方法と同様の方法によりサイクル特性を評価した。比較例8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14及び比較例8における各サイクルでの放電容量の相対値(放電容量比率)を求めた。サイクル数と放電容量の相対値との関係を、図12に示す。実施例14における200サイクル後の放電容量比率は、比較例8における200サイクル後の放電容量比率よりも高く、実施例14が比較例8に比べてサイクル特性に優れることが分かる。
実施例13及び比較例8の各二次電池について、サイクル特性評価後のリチウムイオン二次電池の出力特性を、以下に示す方法で評価した。0.2Cの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0.02Cとした。その後、0.2Cの電流値で終止電圧2.5Vの定電流放電を行い、この放電時の容量を電流値0.2Cにおける放電容量とした。次に、0.2Cの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後(充電終止条件は、電流値0.02Cとした。)、0.5Cの電流値で終止電圧2.5Vの定電流放電を行い、この放電時の容量を電流値0.5Cにおける放電容量とした。同様の充放電から1C、2Cの放電容量を評価した。以下の式により出力特性を算出した。実施例13及び比較例8の評価結果を図13に示す。
放電容量維持率(%)=(電流値0.2C、0.5C、1C、2Cにおける放電容量/電流値0.2Cにおける放電容量)×100
[正極の作製]
正極活物質としてのニッケルコバルトアルミニウム酸リチウム(95質量%)に、導電剤としてアセチレンブラック(AB)(3質量%)と、結着剤(2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3.0g/cm3まで圧密化して、正極を得た。
実施例1と同様の方法により負極を得た。
実施例1と同様の方法により、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、上述した化合物Aを0.1質量%(電解液全量基準)添加したものを使用した。
実施例15において、化合物Aを使用しなかった以外は、実施例13と同様にしてリチウムイオン二次電池を作製した。
実施例15において、化合物Aに代えて、FECを電解液全量基準で0.5質量%添加したこと以外は、実施例15と同様にしてリチウムイオン二次電池を作製した。
実施例5~6及び比較例4における方法と同様の方法により、実施例15及び比較例9~10の各二次電池の初回充放電を実施した。
実施例15及び比較例9~10の各二次電池について、実施例5~6及び比較例4における方法(上限電圧を4.2Vとしたときの方法)と同様の方法により各二次電池の抵抗を測定した。測定結果を図14に示す。
実施例15及び比較例9~10の各二次電池を7日間80℃で保管した。1日毎に二次電池の体積をアルキメデス法に基づく電子比重計(電子比重計MDS-300、アルファミラージュ社製)により測定し、保管前(0日目)の二次電池の体積との差をそれぞれ求めた。結果を図15に示す。
Claims (8)
- 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。
- 正極と、負極と、請求項1~3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。
- 前記負極は炭素材料を含有する、請求項4に記載の電気化学デバイス。
- 前記炭素材料は黒鉛を含有する、請求項5に記載の電気化学デバイス。
- 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5又は6に記載の電気化学デバイス。
- 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4~7のいずれか一項に記載の電気化学デバイス。
Priority Applications (5)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2019521311A JP7147754B2 (ja) | 2017-06-01 | 2018-05-31 | 電解液及び電気化学デバイス |
CN201880035265.1A CN110710046B (zh) | 2017-06-01 | 2018-05-31 | 电解液和电化学装置 |
KR1020197036191A KR20200012886A (ko) | 2017-06-01 | 2018-05-31 | 전해액 및 전기화학 디바이스 |
EP18810837.7A EP3637529A4 (en) | 2017-06-01 | 2018-05-31 | ELECTROLYTE SOLUTION AND ELECTROCHEMICAL DEVICE |
US16/615,640 US11444325B2 (en) | 2017-06-01 | 2018-05-31 | Electrolytic solution and electrochemical device |
Applications Claiming Priority (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JPPCT/JP2017/020484 | 2017-06-01 | ||
PCT/JP2017/020484 WO2018220799A1 (ja) | 2017-06-01 | 2017-06-01 | 電解液及び電気化学デバイス |
JP2018-032310 | 2018-02-26 | ||
JP2018032310 | 2018-02-26 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2018221676A1 true WO2018221676A1 (ja) | 2018-12-06 |
Family
ID=64454777
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/JP2018/021036 WO2018221676A1 (ja) | 2017-06-01 | 2018-05-31 | 電解液及び電気化学デバイス |
Country Status (7)
Country | Link |
---|---|
US (1) | US11444325B2 (ja) |
EP (1) | EP3637529A4 (ja) |
JP (1) | JP7147754B2 (ja) |
KR (1) | KR20200012886A (ja) |
CN (1) | CN110710046B (ja) |
TW (1) | TWI773765B (ja) |
WO (1) | WO2018221676A1 (ja) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPWO2019188757A1 (ja) * | 2018-03-29 | 2021-04-15 | パナソニックIpマネジメント株式会社 | 電気化学デバイス |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN102372732A (zh) * | 2010-08-27 | 2012-03-14 | 中国科学院广州能源研究所 | 有机硅醚室温离子液体电解质材料及其在电化学储能器件中的应用 |
CN102723528A (zh) * | 2012-06-06 | 2012-10-10 | 中国科学院广州能源研究所 | 两性离子液体电解质材料及其制备与在锂电池电解液中的应用 |
WO2014059709A1 (zh) * | 2012-10-15 | 2014-04-24 | 中国科学院广州能源研究所 | 含聚醚链有机卤硅烷及其在非水系锂离子电池电解液中的应用 |
JP2015005329A (ja) | 2012-06-13 | 2015-01-08 | セントラル硝子株式会社 | 非水電解液電池用電解液、及びこれを用いた非水電解液電池 |
WO2016054621A1 (en) * | 2014-10-03 | 2016-04-07 | Silatronix, Inc. | Functionalized silanes and electrolyte compositions and electrochemical devices containing them |
Family Cites Families (29)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3053874A (en) | 1959-12-21 | 1962-09-11 | Union Carbide Corp | Process for the production of cyanoalkylfluorosilane |
JPH03236168A (ja) | 1990-02-13 | 1991-10-22 | Nippon Telegr & Teleph Corp <Ntt> | 化学電池 |
EP0532408A1 (fr) * | 1991-09-13 | 1993-03-17 | Saint-Gobain Vitrage International | Polymère conducteur protonique, application en tant qu'électrolyte dans des dispositifs électrochimiques |
JP2001185212A (ja) | 1999-12-22 | 2001-07-06 | Tonen Chem Corp | 非水電解液及び該電解液を含む電池 |
JP2003092153A (ja) * | 2001-09-18 | 2003-03-28 | Fuji Photo Film Co Ltd | 電解質組成物、光電変換素子及び光電池 |
US8076032B1 (en) | 2004-02-04 | 2011-12-13 | West Robert C | Electrolyte including silane for use in electrochemical devices |
US20090088583A1 (en) * | 2007-10-01 | 2009-04-02 | West Robert C | Organosilicon Amine-Based Electrolytes |
FR2933240B1 (fr) * | 2008-06-25 | 2010-10-22 | Commissariat Energie Atomique | Electrolyte non-aqueux pour accumulateur au lithium a tension elevee |
CN101870711B (zh) * | 2009-04-24 | 2014-09-17 | 中国科学院福建物质结构研究所 | 一种三(三甲基硅基)磷酸酯的合成方法 |
JP5867399B2 (ja) | 2010-09-02 | 2016-02-24 | 日本電気株式会社 | 二次電池 |
JP5781293B2 (ja) | 2010-11-16 | 2015-09-16 | 株式会社Adeka | 非水電解液二次電池 |
WO2012120597A1 (ja) * | 2011-03-04 | 2012-09-13 | 株式会社デンソー | 電池用非水電解液及び該電解液を用いた非水電解液二次電池 |
KR101437073B1 (ko) | 2012-06-08 | 2014-09-02 | 주식회사 엘지화학 | 리튬 이차전지용 비수 전해액 및 이를 구비한 리튬 이차전지 |
WO2014115195A1 (ja) * | 2013-01-28 | 2014-07-31 | 株式会社Gsユアサ | 非水電解質二次電池 |
US9437371B2 (en) * | 2013-06-04 | 2016-09-06 | Silatronix, Inc. | Nitrile-substituted silanes and electrolyte compositions and electrochemical devices containing them |
CN103401019B (zh) * | 2013-08-08 | 2016-03-16 | 东莞市杉杉电池材料有限公司 | 硅氮烷添加剂及应用其制备的防止钢壳腐蚀的锂离子电池电解液 |
DE102013224159A1 (de) * | 2013-11-26 | 2015-05-28 | Wacker Chemie Ag | Silylierte cyclische Phosphonamide |
WO2015098471A1 (ja) * | 2013-12-25 | 2015-07-02 | 旭化成株式会社 | シリル基含有化合物を含む電解液添加用組成物、該組成物を含む非水蓄電デバイス用電解液、及び該電解液を含むリチウムイオン二次電池 |
JP2016018844A (ja) | 2014-07-07 | 2016-02-01 | パナソニック株式会社 | キャパシタ用非水電解液及びキャパシタ |
EP3186262B1 (en) | 2014-08-27 | 2020-01-29 | Arkema, Inc. | Fluorosilicon nitrile compounds |
WO2016054493A1 (en) | 2014-10-02 | 2016-04-07 | Silatronix, Inc. | Organosilicon-containing electrolyte compositions having enhanced electrochemical and thermal stability |
US10541444B2 (en) | 2014-12-26 | 2020-01-21 | Samsung Sdi Co., Ltd. | Rechargeable lithium battery |
JP6438299B2 (ja) * | 2014-12-26 | 2018-12-12 | 三星エスディアイ株式会社Samsung SDI Co., Ltd. | リチウムイオン二次電池 |
FR3033945B1 (fr) * | 2015-03-16 | 2017-03-03 | Arkema France | Formulation d'electrolyte pour les batteries lithium-ion |
US9466857B1 (en) * | 2015-06-22 | 2016-10-11 | Wildcat Discovery Technologies, Inc. | Electrolyte formulations for lithium ion batteries |
CN105037928A (zh) * | 2015-07-01 | 2015-11-11 | 昆明亘宏源科技有限公司 | 一种电解阴极板高性能绝缘夹边条的制备方法 |
CN106025358B (zh) | 2016-06-27 | 2018-12-07 | 中国科学院广州能源研究所 | 一种双氰基功能化的有机硅胺电解质材料 |
CN108713272B (zh) | 2017-01-12 | 2021-05-18 | 株式会社Lg化学 | 非水电解质溶液以及包括所述非水电解质溶液的锂二次电池 |
US10273253B1 (en) | 2017-10-10 | 2019-04-30 | Ppg Industries Ohio, Inc. | Method for producing an ionic liquid |
-
2018
- 2018-05-31 KR KR1020197036191A patent/KR20200012886A/ko not_active Application Discontinuation
- 2018-05-31 EP EP18810837.7A patent/EP3637529A4/en not_active Withdrawn
- 2018-05-31 US US16/615,640 patent/US11444325B2/en active Active
- 2018-05-31 WO PCT/JP2018/021036 patent/WO2018221676A1/ja active Application Filing
- 2018-05-31 JP JP2019521311A patent/JP7147754B2/ja active Active
- 2018-05-31 CN CN201880035265.1A patent/CN110710046B/zh active Active
- 2018-06-01 TW TW107118910A patent/TWI773765B/zh active
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN102372732A (zh) * | 2010-08-27 | 2012-03-14 | 中国科学院广州能源研究所 | 有机硅醚室温离子液体电解质材料及其在电化学储能器件中的应用 |
CN102723528A (zh) * | 2012-06-06 | 2012-10-10 | 中国科学院广州能源研究所 | 两性离子液体电解质材料及其制备与在锂电池电解液中的应用 |
JP2015005329A (ja) | 2012-06-13 | 2015-01-08 | セントラル硝子株式会社 | 非水電解液電池用電解液、及びこれを用いた非水電解液電池 |
WO2014059709A1 (zh) * | 2012-10-15 | 2014-04-24 | 中国科学院广州能源研究所 | 含聚醚链有机卤硅烷及其在非水系锂离子电池电解液中的应用 |
WO2016054621A1 (en) * | 2014-10-03 | 2016-04-07 | Silatronix, Inc. | Functionalized silanes and electrolyte compositions and electrochemical devices containing them |
Non-Patent Citations (1)
Title |
---|
See also references of EP3637529A4 |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPWO2019188757A1 (ja) * | 2018-03-29 | 2021-04-15 | パナソニックIpマネジメント株式会社 | 電気化学デバイス |
Also Published As
Publication number | Publication date |
---|---|
JPWO2018221676A1 (ja) | 2020-04-09 |
US20200168952A1 (en) | 2020-05-28 |
KR20200012886A (ko) | 2020-02-05 |
TWI773765B (zh) | 2022-08-11 |
EP3637529A1 (en) | 2020-04-15 |
EP3637529A4 (en) | 2021-01-20 |
CN110710046A (zh) | 2020-01-17 |
TW201904123A (zh) | 2019-01-16 |
US11444325B2 (en) | 2022-09-13 |
CN110710046B (zh) | 2022-11-08 |
JP7147754B2 (ja) | 2022-10-05 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
WO2018221676A1 (ja) | 電解液及び電気化学デバイス | |
WO2020116583A1 (ja) | 電解液及び電気化学デバイス | |
JP7074132B2 (ja) | 電解液及び電気化学デバイス | |
WO2020116574A1 (ja) | 電解液及び電気化学デバイス | |
JP2020004542A (ja) | 負極及び電気化学デバイス | |
JP7415947B2 (ja) | 電解液及び電気化学デバイス | |
US11411250B2 (en) | Electrolytic solution and electrochemical device | |
WO2020027004A1 (ja) | 電解液及び電気化学デバイス | |
WO2020116578A1 (ja) | 電解液及び電気化学デバイス | |
WO2020027003A1 (ja) | 電解液及び電気化学デバイス | |
WO2018220799A1 (ja) | 電解液及び電気化学デバイス | |
WO2018220795A1 (ja) | 電解液及び電気化学デバイス |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 18810837 Country of ref document: EP Kind code of ref document: A1 |
|
ENP | Entry into the national phase |
Ref document number: 2019521311 Country of ref document: JP Kind code of ref document: A |
|
NENP | Non-entry into the national phase |
Ref country code: DE |
|
ENP | Entry into the national phase |
Ref document number: 20197036191 Country of ref document: KR Kind code of ref document: A |
|
WWE | Wipo information: entry into national phase |
Ref document number: 2018810837 Country of ref document: EP |
|
ENP | Entry into the national phase |
Ref document number: 2018810837 Country of ref document: EP Effective date: 20200102 |