WO2018123324A1 - リチウムイオン二次電池用電極およびリチウムイオン二次電池 - Google Patents
リチウムイオン二次電池用電極およびリチウムイオン二次電池 Download PDFInfo
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- WO2018123324A1 WO2018123324A1 PCT/JP2017/041205 JP2017041205W WO2018123324A1 WO 2018123324 A1 WO2018123324 A1 WO 2018123324A1 JP 2017041205 W JP2017041205 W JP 2017041205W WO 2018123324 A1 WO2018123324 A1 WO 2018123324A1
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- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
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- 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
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- H01M4/00—Electrodes
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- H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
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- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
- H01M4/621—Binders
- H01M4/622—Binders being polymers
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- 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
- H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
- H01M4/624—Electric conductive fillers
- H01M4/625—Carbon or graphite
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- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/42—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
- H01M10/4235—Safety or regulating additives or arrangements in electrodes, separators or electrolyte
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- H—ELECTRICITY
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- 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
- H01M2004/021—Physical characteristics, e.g. porosity, surface area
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- 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
- H01M2004/023—Gel electrode
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- H—ELECTRICITY
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- 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
- H01M2300/0028—Organic electrolyte characterised by the solvent
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- H—ELECTRICITY
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- 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
- H01M2300/0045—Room temperature molten salts comprising at least one organic ion
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- H—ELECTRICITY
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- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M2300/00—Electrolytes
- H01M2300/0085—Immobilising or gelification of electrolyte
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- H—ELECTRICITY
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- 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
- H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
- H01M4/131—Electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx
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- 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
- H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
- H01M4/133—Electrodes based on carbonaceous material, e.g. graphite-intercalation compounds or CFx
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- 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 electrode for a lithium ion secondary battery and a lithium ion secondary battery.
- Lithium ion secondary batteries have a high energy density and are attracting attention as batteries for electric vehicles and power storage.
- a zero emission electric vehicle battery electric vehicle, Battery Electric Vehicle (hereinafter referred to as BEV)
- BEV Battery Electric Vehicle
- a hybrid electric vehicle that is equipped with both an engine and a secondary battery
- a system power supply There is a plug-in electric car to be charged from.
- a storage battery with a high energy density is required in order to increase the travel distance for one charge.
- the conventional lithium ion secondary battery it is necessary to add a battery cooling mechanism, and the problem is that the energy density of the battery system as a whole is reduced. If the heat resistance of the lithium ion secondary battery is improved and the cooling mechanism can be omitted, the above-described problems can be solved.
- the organic electrolyte used in the conventional lithium ion secondary battery In order to improve the heat resistance of the lithium ion secondary battery, it is necessary to improve the organic electrolyte used in the conventional lithium ion secondary battery.
- One solution is to change the organic electrolyte to an electrolyte with excellent heat resistance, and the electrolyte is a liquid in which a lithium salt is dissolved in an ionic liquid.
- Patent Document 1 discloses a non-aqueous electrolyte secondary that includes a fibrous resin skeleton base material and an active material, and the active material is dispersed in voids of the fibrous resin skeleton base material.
- a battery electrode active material layer is disclosed.
- Patent Document 2 discloses a non-aqueous electrolyte secondary battery including a positive electrode including a positive electrode active material, a negative electrode including a negative electrode active material, and a non-aqueous electrolyte. At least one of the positive electrode and the negative electrode includes cellulose fibers.
- a nonaqueous electrolyte characterized in that at least a part of the cellulose fiber has a thickness of 0.01 to 50 ⁇ m and a ratio of the length L to the thickness T (L / T) is 5 times or more.
- a secondary battery is disclosed.
- the object of the present invention is to prevent the electrolyte from seeping out from the electrode.
- the nanofiber is a cellulose-based or polyacrylate-based resin, the nanofiber has a wire diameter of 0.01 ⁇ m or more and 1 ⁇ m or less, and is measured from a lithium ion secondary battery electrode measured by a mercury porosimeter and an ionic liquid and
- the electrode for lithium ion secondary batteries whose average value of the pore diameter of the electrode mixture layer except lithium salt is 0.001 micrometer or more and 0.5 micrometer or less.
- the cross-sectional structure of the lithium ion secondary battery of this invention is shown.
- the result of the Example and comparative example of this invention is shown.
- the result of the Example and comparative example of this invention is shown.
- FIG. 1 schematically shows the internal structure of the lithium ion secondary battery 101.
- the lithium ion secondary battery 101 is an electrochemical device that can store or use electrical energy by occlusion / release of lithium ions to and from an electrode in a nonaqueous electrolyte. This is called by another name of a lithium ion battery, a non-aqueous electrolyte secondary battery, and a non-aqueous electrolyte secondary battery, but any battery is also the subject of the present invention.
- the lithium ion secondary battery 101 has a configuration in which an electrode group including a positive electrode 107, a negative electrode 108, and a semi-solid electrolyte layer 109 is housed in a sealed state in a battery container 102.
- the semi-solid electrolyte layer 109 is formed at least on the surface of the positive electrode 107 or the negative electrode 108 and has an integral structure.
- the semi-solid electrolyte layer 109 has a function of a layer that allows lithium ions to permeate by electrically insulating the positive electrode 107 and the negative electrode 108 and holding an electrolyte solution L described later.
- the electrode group can employ various configurations such as a configuration in which strip-shaped electrodes are stacked, a configuration in which strip-shaped electrodes are wound and formed into a cylindrical shape or a flat shape.
- a region where the electrolyte solution L is insufficient in a part of the positive electrode 107 or the negative electrode 108 is generated. As a result, the performance of the lithium ion secondary battery 101 may be reduced.
- the semi-solid electrolyte layer 109 is obtained by dissolving a lithium salt in an organic solvent or an ionic liquid, and SiO 2 , Al 2 O 3 , AlOOH, TiO 2 , ZrO 2 , BaTiO 3 , CaO, MgO, Li 7 La 3 Zr 2 O 12. It is a sheet-like material mixed with an oxide such as. This is characterized in that there is no fluid electrolyte and it is difficult for the electrolyte to leak out.
- the semi-solid electrolyte layer 109 serves as a medium for transmitting lithium ions between the positive electrode 107 and the negative electrode 108 and also functions as an electronic insulator, thereby preventing a short circuit between the positive electrode 107 and the negative electrode 108.
- the ionic liquid is a compound that dissociates into a cation and an anion at room temperature, and maintains a liquid state.
- the ionic liquid is sometimes referred to as an ionic liquid, a low melting point molten salt or a room temperature molten salt.
- the electrolytic solution L is a solution obtained by dissolving a lithium salt in the organic solvent or ionic liquid used for the semi-solid electrolyte layer 109. This liquid is absorbed inside the pores of the electrode of the present invention. As in the case of the semi-solid electrolyte layer 109, the feature of the present invention is that the electrolytic solution is less likely to leak from the electrode.
- the electrolytic solution L may be preliminarily contained in the semi-solid electrolyte layer 109, or a sheet not containing an electrolyte may be sandwiched between the positive electrode 107 and the negative electrode 108, and the electrolytic solution may be added after the electrode group is assembled. . When the electrolytic solution is added, the electrolytic solution is supplied from an injection port 106 described later to the electrode group.
- the battery container 102 can be selected from an arbitrary shape such as a cylindrical shape, a flat oval shape, and a square shape in accordance with the shape of the electrode group.
- the battery case 102 accommodates the electrode group from the opening provided in the upper part, and then the opening is closed and sealed by the lid 103.
- the lid 103 is joined to the opening of the battery case 102 by, for example, welding, caulking, adhesion, or the like, and the outer edge of the lid 103 is hermetically sealed.
- the lid 103 has a liquid injection port for injecting the electrolyte L into the battery container 102 after sealing the opening of the battery container 102.
- the liquid injection port is sealed by the liquid injection port 106 after the electrolytic solution L is injected into the battery container 102.
- a safety mechanism to the liquid injection port 106.
- a pressure valve for releasing the pressure inside the battery container 102 may be provided.
- the positive electrode external terminal 104 and the negative electrode external terminal 105 are fixed to the lid 103 via an insulating seal material 112, and a short circuit between the positive electrode external terminal 104 and the negative electrode external terminal 105 is prevented by the insulating seal material 112.
- the positive external terminal 104 is connected to the positive electrode 107 via the positive lead 110 and the negative external terminal 105 is connected to the negative 108 via the negative lead 111.
- the material of the insulating sealing material 112 can be selected from fluororesins, thermosetting resins, glass hermetic seals, etc., and any insulating material that does not react with the electrolyte L and has excellent airtightness should be used. Can do.
- the insulating sheet 113 is also inserted between the electrode group and the battery container 102 so that the positive electrode 107 and the negative electrode 108 are not short-circuited through the battery container 102.
- the positive electrode 107 includes a positive electrode active material (electrode active material), a conductive agent, a binder, and a current collector.
- the positive electrode active material include LiCoO 2 , LiNiO 2 , and LiMn 2 O 4 .
- LiMnPO 4 may enumerate.
- LiNi 1/3 Mn 1/3 Co 1/3 O 2 was selected as the positive electrode active material.
- the present invention is not limited to the positive electrode material, and is not limited to these materials.
- LiNi 1/3 Co 1/3 Mn 1/3 O 2 was used as the positive electrode active material, but it is also possible to use a Li 2 MnO 3 —LiMnO 2 solid solution positive electrode having a higher capacity than that.
- a high power 5V positive electrode such as LiNi 0.5 Mn 1.5 O 4 ) may be used.
- these high-capacity materials or high-power materials are used, the above-mentioned mixture thickness can be reduced, and the electrode area that can be stored in the battery can be increased. As a result, the resistance of the battery can be reduced to enable high output, and at the same time, the capacity of the battery can be increased as compared with the case of using a LiNi 1/3 Co 1/3 Mn 1/3 O 2 positive electrode.
- a powder of secondary particles (granulated primary particles) of the positive electrode active material is collected.
- primary powder may be used without granulation, such as lithium iron phosphate.
- the presence or absence of granulation and the difference between primary particles or secondary particles are not important in the present invention.
- the particle diameter of the positive electrode active material is defined to be equal to or less than the thickness of the positive electrode mixture layer (electrode mixture layer).
- the coarse particles are removed in advance by sieving classification, wind classification or the like, and particles having a thickness of the positive electrode mixture layer or less are prepared.
- the positive electrode active material may be used as primary particles that are not granulated, or may be granulated to use secondary particles.
- a method for producing a positive electrode will be described assuming that secondary particles are used.
- the average particle diameter (D 50 ) of the positive electrode active material of the present invention was measured by a laser scattering method.
- the average particle diameter D 50 is a sample of the positive electrode active material was suspended in water, a laser scattering type particle size measuring apparatus (for example, Microtrac) are measured using a.
- D 50 is defined as the particle size when the ratio (volume fraction) to the volume of the entire sample is 50%. If the range is 2 to 20 ⁇ m, it is applicable to the present invention.
- D 50 is 2 to 10 ⁇ m
- a positive electrode slurry is prepared using a positive electrode active material, and applied to a current collector to produce a positive electrode.
- the positive electrode slurry is prepared by mixing a binder and the nanofiber of the present invention in a positive electrode active material, and further adding a solvent such as water or 1-methyl-2-pyrrolidone.
- the nanofiber is a nanofiber made of a cellulose-based or polyacrylate-based resin. These resins are materials having no hydroxyl group. This is because if there is a hydroxyl group, it reacts with the electrolyte and the conductivity of lithium ions decreases. In addition, since the resin has polarity and contains a large amount of oxygen atoms that are easily coordinated to lithium ions, the electrolyte is easily wetted by the resin. As a result, the amount of electrolyte retained by the nanofiber increases.
- the wire diameter of the nanofiber is preferably 0.01 ⁇ m or more and 0.1 ⁇ m or less. If the fiber diameter of the nanofiber is not small, it cannot enter the gap between the particles of the positive electrode active material. When the wire diameter is larger than 0.1 ⁇ m, for example, 0.5 ⁇ m, the gap between the positive electrode active material particles is closed to inhibit the diffusion of lithium ions. Further, when the nanofibers enter between the positive electrode active material particles, the electrical conductivity of the nanofibers is deteriorated because the electrical resistance of the nanofibers is high.
- the length of the nanofiber is preferably 0.1 ⁇ m or more and 50 ⁇ m or less, and if it is 0.1 ⁇ m or more and 10 ⁇ m or less, the density of the positive electrode 107 is increased, which is particularly effective for increasing the capacity of the battery. is there.
- the solvent of the positive electrode slurry is dried, and if necessary, the positive electrode is compression molded to complete the positive electrode 107.
- the pore diameter of the positive electrode mixture layer before adding the electrolyte of the present invention is measured using a mercury porosimeter.
- the appropriate average pore diameter is 0.001 ⁇ m or more and 0.5 ⁇ m or less. Since the pore diameter is small, the retention force of the electrolyte due to the capillary force is increased in addition to the retention force of the nanofiber, which is preferable.
- the pore diameter in the positive electrode mixture layer is the pore diameter of the void excluding the electrolyte and its solvent. That is, the pore diameter of the space excluding the positive electrode active material, the conductive agent, and the binder. It can be measured by the following means. First, an electrolyte solvent component such as tetraglyme is eluted using a low-viscosity organic solvent or water. Any solvent can be used as long as it can dissolve the electrolyte and the solvent without dissolving the binder and the nanofibers. When the positive electrode is immersed in alcohol such as methanol or ethanol, dimethyl ether, acetone, dimethoxy ether, or water, the electrolyte solvent is eluted from the positive electrode.
- alcohol such as methanol or ethanol, dimethyl ether, acetone, dimethoxy ether, or water
- the positive electrode is taken out and dried in vacuum to remove the low-viscosity organic solvent or water, and the electrolyte solvent is removed from the pores of the positive electrode.
- the pore diameter is measured using a mercury porosimeter. In this specification, the median diameter is defined as the average pore diameter. The measurement results are shown in the column of average pore diameter in FIG.
- the positive electrode active material of this example is LiNi 1/3 Co 1/3 Mn 1/3 O 2 , and the average particle diameter and the amount added in the positive electrode are shown in the column of the electrode active material in FIG.
- the types and weight compositions of resin fibers (nanofibers), conductive agents, and binders are shown in FIG. ⁇ ⁇
- the types of nanofibers described in FIG. 2 are indicated by symbols, CMCa means carboxymethylcellulose, and ACC means cellulose acetate.
- the conductive agent is acetylene black or carbon nanotube, and is represented as CB or CNT in FIG.
- PVDF Polyvinylidene fluoride
- the positive electrode active material has high resistance, a conductive agent is required, but a part of it can be replaced with carbon fiber. Since the carbon fiber connects the particles of the positive electrode active material, the electronic resistance is easily reduced. When blended with nanofibers, the two are intertwined, and the amount of electrolyte solution retained in the nanofiber is easily increased. Addition of carbon fiber increases both conductivity and electrolyte retention.
- the carbon fiber any material such as carbon nanotube, vapor-grown carbon, carbon fiber obtained by carbonizing polyacrylonitrile fiber can be used.
- the carbon fiber has a wire diameter of 0.001 ⁇ m or more and 1 ⁇ m or less and a length of 0.1 ⁇ m or more and 10 ⁇ m or less, it can be used in the present invention.
- the thickness is 0.01 ⁇ m or more and 0.1 ⁇ m or less, the nanofibers are entangled and particularly effective in increasing the amount of electrolyte retained.
- the weight composition of the carbon fiber is 1 wt% or more and 90 wt% or less with respect to the weight of the nanofiber and the carbon fiber, it can be applied to the present invention, and particularly 10 wt% or more and 30 wt% or less. Then, it becomes possible to reduce the electronic resistance of the positive electrode without deteriorating the affinity between the nanofiber and the electrolytic solution, that is, without reducing the amount of retained electrolytic solution.
- the solvent used for preparing the slurry may be any solvent that can dissolve the binder, and 1-methyl-2-pyrrolidone was used for PVDF. Depending on the type of binder, the solvent is selected. A known kneader or disperser was used for the dispersion treatment of the positive electrode material.
- a positive electrode slurry in which a positive electrode active material, a conductive agent, a binder, and an organic solvent are mixed is attached to a current collector by a doctor blade method, a dipping method, a spray method, etc., and then the organic solvent is dried and the positive electrode is removed by a roll press.
- a positive electrode can be produced by pressure molding.
- the mixture density of the positive electrode mixture layer is 2 to 3 g / cm 3 or more, and it is necessary to closely adhere the conductive agent and the positive electrode active material to reduce the electronic resistance of the positive electrode mixture layer.
- an aluminum foil having a thickness of 10 to 100 ⁇ m, or an aluminum perforated foil having a thickness of 10 to 100 ⁇ m and a hole diameter of 0.1 to 10 mm, an expanded metal, a metal foam plate, etc. are used.
- aluminum, stainless steel, titanium, etc. can also be applied.
- any material can be used for the current collector without being limited by the material, shape, manufacturing method, or the like as long as it does not change during the use of the battery, such as dissolution and oxidation.
- the thickness of the positive electrode mixture layer is desirably equal to or greater than the average particle diameter of the positive electrode active material. This is because, when the thickness is an average particle diameter, the electron conductivity between adjacent particles is deteriorated.
- the average particle diameter (D 50 ) of the positive electrode active material of the present invention is measured by a laser scattering method, and the range thereof is 2 to 20 ⁇ m, and particularly preferably 2 to 8 ⁇ m. When this positive electrode active material is used and the thickness of the positive electrode mixture layer is 20 ⁇ m or more, the effects of the present invention can be obtained.
- the upper limit of the thickness of the positive electrode mixture layer is desirably 80 ⁇ m or less.
- the positive electrode mixture layer has a thickness of 80 ⁇ m or more, variation occurs in the charge level of the positive electrode active material near the surface of the positive electrode mixture layer and the current collector surface, unless a large amount of conductive agent is added to the positive electrode mixture. This is because uneven charge / discharge occurs. When the amount of the conductive agent is increased, the positive electrode volume becomes bulky and the energy density of the battery decreases.
- the negative electrode 108 includes a negative electrode active material (electrode active material), a binder, and a current collector.
- the negative electrode active material is natural graphite coated with amorphous carbon.
- a method of forming amorphous carbon on the surface of natural graphite there is a method of depositing pyrolytic carbon on the negative electrode active material powder.
- low molecular hydrocarbons such as ethane, propane and butane
- an inert gas such as argon
- hydrogen is desorbed from the hydrocarbons on the surface of the negative electrode active material particles, and the negative electrode active Carbon is deposited on the surface of the material particles.
- Carbon is an amorphous form.
- heat treatment is performed at 300 to 1000 ° C. in an inert gas atmosphere, so that hydrogen and oxygen are desorbed in the form of hydrogen, carbon monoxide, and carbon dioxide. Only carbon can be deposited on the surface of the negative electrode active material.
- a gas in which 1% propane and 99% argon were mixed was brought into contact with the negative electrode active material at 1000 ° C. to deposit carbon.
- the amount of carbon deposited is desirably in the range of 1 to 30% by weight. In this example, 2% by weight of carbon was deposited on the surface of the negative electrode active material. Carbon coating not only increases the discharge capacity at the first cycle, but is also effective for increasing cycle life characteristics and rate characteristics.
- the average particle diameter (D 50 ) of the negative electrode active material of the present invention was measured by a laser scattering method.
- the average particle diameter D 50 is a sample of the negative electrode active material was suspended in water, a laser scattering type particle size measuring apparatus (for example, Microtrac) are measured using a.
- D 50 is defined as the particle size when the ratio (volume fraction) to the volume of the entire sample is 50%. If the range is 2 to 20 ⁇ m, it is applicable to the present invention. In particular, when D 50 is 5 to 20 ⁇ m, it is possible to provide a well-balanced negative electrode that suppresses an increase in irreversible capacity due to a decrease in particle size and has improved electrolyte retention capability.
- a negative electrode slurry is prepared using a negative electrode active material, and a negative electrode is produced by applying it to a current collector.
- the negative electrode slurry is prepared by mixing a binder and the nanofiber of the present invention in a negative electrode active material, and further adding a solvent such as water or 1-methyl-2-pyrrolidone.
- the nanofiber is a nanofiber made of a cellulose-based or polyacrylate-based resin. These resins are easy to wet the electrolyte and have a strong electrolyte holding power.
- the wire diameter of the nanofiber is preferably 0.01 ⁇ m or more and 0.1 ⁇ m or less. If the fiber diameter of the nanofiber is not thin, it cannot enter the gap between the particles of the negative electrode active material.
- the wire diameter is larger than 0.1 ⁇ m, for example, 0.5 ⁇ m, not only the gap between the negative electrode active material particles is blocked and the diffusion of lithium ions is inhibited, but also nanofibers penetrate between the negative electrode active material particles. , The transmission of electrons and lithium ions between particles deteriorates.
- the nanofiber wire diameter is smaller than 0.01 ⁇ m, the specific surface area of the nanofiber increases, so that the viscosity of the negative electrode slurry increases, and the surface of the negative electrode easily becomes uneven. becomes difficult.
- the length of the nanofiber is preferably 0.1 ⁇ m or more and 50 ⁇ m or less, and if it is 0.1 ⁇ m or more and 10 ⁇ m or less, the density of the negative electrode is increased, which is particularly effective for increasing the capacity of the battery.
- carbon fiber may be added to the negative electrode. It is possible to increase the amount of electrolyte retained in the negative electrode while further reducing the resistance of the negative electrode. Applicable carbon fiber types and addition conditions are the same as in the case of the positive electrode.
- the negative electrode slurry After applying the negative electrode slurry to the current collector, the negative electrode slurry is dried, and if necessary, the negative electrode is compression molded to complete the negative electrode.
- the pore diameter of the negative electrode mixture layer (electrode mixture layer) before adding the electrolyte of the present invention is measured using a mercury porosimeter.
- the appropriate average pore diameter is 0.001 ⁇ m or more and 0.5 ⁇ m or less. Since the pore diameter is small, in addition to the holding power of the nanofiber, the holding power of the electrolyte due to the capillary force increases.
- the pore diameter in the negative electrode mixture is the pore diameter of the void excluding the electrolyte and its solvent. That is, the pore diameter of the space excluding the negative electrode active material, the conductive agent, and the binder. It can be measured by the following means. First, an electrolyte solvent component such as tetraglyme is eluted using a low-viscosity organic solvent or water. When the negative electrode is immersed in alcohol such as methanol or ethanol, dimethyl ether, acetone, dimethoxy ether, or water, the electrolyte solvent is eluted from the negative electrode.
- alcohol such as methanol or ethanol, dimethyl ether, acetone, dimethoxy ether, or water
- the negative electrode is taken out and dried in vacuum to remove the low-viscosity organic solvent or water, and the electrolyte solvent is removed from the pores of the negative electrode.
- the pore diameter is measured using a mercury porosimeter. In this specification, the median diameter is defined as the average pore diameter. The measurement results are shown in the column of average pore diameter in FIG.
- the weight composition of the negative electrode active material, resin fiber (nanofiber), conductive agent, and binder is shown in FIG.
- the electrode active material described as graphite is an example relating to the negative electrode.
- Examples 9, 10, 11, and 12 are examples relating to the negative electrode of the present invention.
- the conductive agent is acetylene black or carbon nanotube, and is abbreviated as CB or CNT in FIG.
- As the binder styrene-butadiene rubber (SBR) was used.
- SBR styrene-butadiene rubber
- PVDF Polyvinylidene fluoride
- a styrene butadiene rubber and carboxymethyl cellulose binder may be used instead of PVDF.
- fluorine rubber, ethylene / propylene rubber, polyacrylic acid, polyimide, polyamide and the like can be used, and there is no restriction in the present invention. Any binder that does not decompose on the surface of the negative electrode and does not dissolve in the electrolyte can be used in the present invention.
- the solvent used for preparing the negative electrode slurry may be any solvent that can dissolve the binder, and 1-methyl-2-pyrrolidone was used for PVDF. Depending on the type of binder, the solvent is selected. For example, when using a styrene butadiene rubber and carboxymethyl cellulose binder, water is used as a solvent. A known kneader and disperser were used for the dispersion treatment of the negative electrode material.
- a known technique such as a doctor blade method, a dipping method, or a spray method can be applied to apply the negative electrode active material layer. It is also possible to form a multilayer mixture layer on the current collector by performing a plurality of times from application to drying. In this example, the coating was performed once on the copper foil by the doctor blade method.
- the thickness of the negative electrode mixture layer is desirably equal to or greater than the average particle diameter of the negative electrode active material. This is because when the thickness of the negative electrode active material is set to the average particle size, the electron conductivity between adjacent particles is deteriorated.
- the thickness of the negative electrode mixture layer is 10 ⁇ m or more, more preferably 15 ⁇ m or more, the effect of the present invention can be obtained.
- the upper limit of the thickness of the negative electrode mixture layer is desirably 50 ⁇ m or less. If it is thicker than that, unless a large amount of conductive agent is added to the negative electrode mixture layer, the charge level of the negative electrode active material near the surface of the negative electrode mixture layer and the current collector surface varies, and uneven charge and discharge occur. It is.
- the negative electrode volume becomes bulky and the energy density of the battery decreases.
- graphite is used as the active material, but silicon, tin, or a compound thereof (oxide, nitride, and alloy with other metals) may be used as the negative electrode active material.
- These active materials are larger than the theoretical capacity of graphite (372 Ah / kg), and a capacity of 500 to 1500 Ah / kg is obtained.
- the above-mentioned mixture thickness can be reduced, and the electrode area that can be accommodated in the battery can be increased.
- the resistance of the battery can be reduced to enable high output, and at the same time, the capacity of the battery can be increased as compared with the case where a graphite negative electrode is used.
- a copper foil having a thickness of 10 to 100 ⁇ m As the current collector that can be used in the present invention, a copper foil having a thickness of 10 to 100 ⁇ m, a copper perforated foil having a thickness of 10 to 100 ⁇ m and a pore diameter of 0.1 to 10 mm, an expanded metal, a foam metal plate, and the like are used. In addition to copper, stainless steel, titanium, nickel, etc. are also applicable. In the present invention, an arbitrary current collector can be used without being limited by the material, shape, manufacturing method and the like. In this example and comparative example, a rolled copper foil having a thickness of 10 ⁇ m was used.
- the electrolyte can be held by adding the electrolyte to the positive electrode or the negative electrode described above and absorbing it into the pores of the electrode.
- a slurry in which an electrolyte, an active material, and a binder are mixed may be prepared, and an electrode may be applied together on a current collector.
- glyme represented by Formula 1 is used as an organic solvent.
- Glyme has ethylene glycol dimethyl ether as a basic unit, and is called monoglyme, diglyme, triglyme, tetraglyme, pentag lime, and hexaglyme in descending order.
- an imide salt can be used, and typical examples thereof include Li (NSO 2 F) 2 (abbreviated as LiFSI) or LiN (SO 2 CF 3 ) 2 (abbreviated as LiTFSI), LiC.
- LiFSI Li (NSO 2 CF 3 ) 2
- LiTFSI LiN (SO 2 CF 3 ) 2
- LiC LiC.
- Examples include 4 BO 8 (lithium bisoxalate borate), CF 3 SO 3 Li (lithium trifluoromethanesulfonate), and LiBF 4 (lithium borofluoride).
- the concentration of the electrolyte is preferably 1 mol or more and 3 mol or less with respect to 1 liter of glyme. CH 3 O— (CH 2
- LiPF 6 or LiBF 4 may be mixed.
- the glyme of Formula 1 may be changed to another solvent (ionic liquid).
- solvent ionic liquid
- EMI-TMS 1-ethyl-3-methylimidazoliumtrifluoromethanesulfonate
- BMP-BTI 1-butyl-1-methylpyrrolidiniumbis (trifluoromethylsulfonyl) imide
- HMI-HFP 1-hexyl-3-methylimidazolium fluorphosphate
- EMIDCA 1-ethyl-3-methylimidazoliumamide
- MOI-TFB azoliumtetrafluoroborate
- An electrolyte layer made of a semi-solid electrolyte (hereinafter referred to as a semi-solid electrolyte layer 109) is inserted between the positive electrode 107 and the negative electrode 108, and lithium ions can be exchanged between the electrodes.
- the semi-solid electrolyte layer 109 has pores formed by aggregates of inert particles, and imide salt and glyme are held therein.
- the pore diameter of the semi-solid electrolyte layer 109 is 0.01 ⁇ m or more and 0.5 ⁇ m or less, and it is possible to provide an electrolyte layer having a low resistance by holding an imide salt and glyme necessary for exchange of lithium ions. Become.
- the volume fraction of inert particles is controlled by the amount of inert particles added.
- the pore diameter of the semi-solid electrolyte layer 109 can be within the range of the present invention depending on the amount of inert particles added.
- the pore diameter of the semi-solid electrolyte layer 109 can also be measured by the same procedure as that of the positive electrode or the negative electrode using a mercury porosimeter.
- a scanning electron micrograph of the surface or cross section of the semi-solid electrolyte layer 109 is taken, and the location of the pores is specified based on the photograph. Assuming a circle in contact with the inner wall of the pore, the diameter of the circle is determined as the pore diameter. The average value of the diameters of the circles can be made the pore diameter of the semi-solid electrolyte layer 109 by image processing.
- the inert particles of the present invention are one kind or a mixture selected from SiO 2 , Al 2 O 3 , AlOOH, TiO 2 , ZrO 2 , CaO, MgO, BaTiO 3 , Li 7 La 3 Zr 2 O 2. Is preferred. In this example, Li 7 La 3 Zr 2 O 2 having an average particle size of 0.1 ⁇ m was used as the inert particles.
- the thickness of the semi-solid electrolyte layer 109 is 1 ⁇ m or more and 100 ⁇ m or less and 5 ⁇ m or more and 25 ⁇ m or less, it is possible to suppress an increase in resistance in the electrolyte layer, which is suitable for improving the performance of the lithium ion secondary battery. is there.
- the thickness is 1 ⁇ m or less, pinholes are formed in the semi-solid electrolyte layer 109, and a short circuit between the positive electrode and the negative electrode is likely to occur.
- the thickness exceeds 100 ⁇ m, the movement distance of lithium ions becomes too large, This is because the resistance required for ion movement increases.
- the semi-solid electrolyte layer 109 may be produced directly on the positive electrode 107 or the negative electrode 108. Alternatively, after the semi-solid electrolyte layer 109 is formed on a support sheet of resin or metal, the semi-solid electrolyte layer 109 may be peeled off from the support sheet and attached to the positive electrode 107 or the negative electrode 108. Inert particles, imide salts and glyme are mixed in a solvent such as 1-methyl-2-pyrrolidone (NMP), and the slurry is applied to the surface of the positive electrode or negative electrode, and the NMP is removed by drying. A solid electrolyte layer 109 is obtained.
- NMP 1-methyl-2-pyrrolidone
- the semi-solid electrolyte layer 109 After the semi-solid electrolyte layer 109 is formed, it may be compressed by a roll press or may be omitted. In addition, it is more preferable to add a binder such as polyvinylidene fluoride or tetrafluoroethylene to the slurry because the mechanical strength of the semi-solid electrolyte layer 109 is increased. In order to disperse the binder, in addition to NMP, a lower alcohol such as ethanol or water may be used.
- a binder such as polyvinylidene fluoride or tetrafluoroethylene
- the positive electrode 107 and the negative electrode 108 on which the semi-solid electrolyte layer 109 is formed are stacked.
- the semi-solid electrolyte layer 109 may be formed on any surface of the positive electrode 107 and the negative electrode 108, or may be formed on both surfaces.
- the semi-solid electrolyte layer 109 functions as a medium for moving lithium ions between the positive electrode and the negative electrode while preventing a short circuit between the positive electrode 107 and the negative electrode 108.
- An insulating sheet 113 is inserted between the electrode disposed at the end of the electrode group and the battery container 102 so that the positive electrode 107 and the negative electrode 108 are not short-circuited through the battery container 102.
- the upper part of the laminate is electrically connected to the positive external terminal 104 and the negative external terminal 105 via the positive lead wire 110 and the negative lead wire 111.
- the positive electrode 107 is connected to the positive electrode external terminal 104 of the lid 103 via the positive electrode lead wire 110.
- the negative electrode 108 is connected to the negative electrode external terminal 105 of the lid 103 via the negative electrode lead wire 111.
- the positive electrode lead wire 110 and the negative electrode lead wire 111 can take any shape such as a wire shape or a plate shape.
- the shape and material of the positive electrode lead wire 110 and the negative electrode lead wire 111 are the same as those of the battery case 102. It can be arbitrarily selected depending on the case.
- the material of the battery container 102 is selected from materials that are corrosion resistant to the electrolyte, such as aluminum, stainless steel, and nickel-plated steel.
- the lid 103 is brought into close contact with the battery container 102 and the whole battery is sealed.
- the lid 103 is attached to the battery container 102 by caulking.
- a known technique such as welding or adhesion may be applied to the method for sealing the battery.
- the liquid injection port 106 is used when an electrolyte is added to the positive electrode 107 or the negative electrode 108. However, when the electrolyte is held in advance by the electrode, the liquid injection port 106 becomes unnecessary and may be deleted.
- the rated capacity (calculated value) of the battery manufactured as an example is 3 Ah.
- FIG. 2 illustrates the electrode specifications of the present invention.
- Examples 1 to 8 are examples in which the present invention is applied to the positive electrode.
- nanofibers made of carboxymethyl cellulose (CMC) were added to the positive electrode.
- the fiber diameter is 0.1 ⁇ m and the fiber length is 5 ⁇ m.
- the amount of nanofiber added was varied from 3 wt% to 13 wt%.
- the average pore diameter of the produced positive electrode was measured using a mercury porosimeter and was in the range of 0.4 ⁇ m to 0.05 ⁇ m.
- Example 4 to Example 6 are examples in which CMC was changed to nanofibers of acetyl cellulose (cellulose acetate, abbreviated as ACC).
- the degree of acetylation of ACC was 55.
- the amount of nanofiber added was varied from 3 wt% to 13 wt%.
- the average pore diameter of the produced positive electrode was in the range of 0.4 ⁇ m to 0.05 ⁇ m.
- Carboxymethylcellulose is an example of cellulose in which hydroxyl groups of unsubstituted cellulose nanofibers are alkylated, and cellulose acetate is an example of cellulose in which hydroxyl groups are acetylated.
- Example 7 and Example 8 are results when a part of the nanofiber is changed to a carbon nanotube (CNT).
- CNT is a powder having a multilayer structure with a diameter of 40 nm to 60 nm.
- Examples 9 to 12 are examples in which the present invention was applied to a graphite negative electrode, and the CMC of Example 1 or the ACC of Example 4 was used for the nanofiber.
- Example 1 to Example 12 the amount of electrolyte retained was measured as follows.
- the electrode was immersed in an equimolar electrolyte solution of LiTFSI and tetraglyme for 30 minutes or more, and after lifting the electrode, the surface was wiped with Kimwipe.
- the amount of electrolyte retained was calculated from the weight increase of the electrode, and it was within ⁇ 5% of the calculated value from the void volume. Tetraglyme vaporized even if the electrode retaining the electrolyte was left at room temperature. Without loss, the weight loss was 5% or less, and almost no electrolyte was lost. From this result, it was found that there was no electrolyte leakage from the electrode pores.
- the electrode of this example is inserted between two medicine-wrapped papers or a polyethylene porous separator and pressed.
- the applied pressure was 3 MPa per unit area of the electrode. Since the weight of the medicine wrapping paper and the polyethylene porous separator did not change, it was confirmed that there was no liquid leakage.
- the semi-solid electrolyte is an electrolyte in which an electrolytic solution in which a lithium salt is dissolved in an organic solvent or an ionic liquid is held on an electrode or an electrolyte layer made of porous particles, and the bleeding of the electrolytic solution is suppressed.
- the semi-solid electrolyte was mixed with 0.1 ⁇ m SiO 2 powder with the composition shown in FIG. 3 to produce a semi-solid electrolyte.
- the ratio of the weight of the electrolyte to the weight of SiO 2 was 40:60.
- PVDF was used for the binder and the thickness of the semisolid electrolyte was 20 ⁇ m.
- Example 12 to Example 21 The result of measuring the discharge capacity by charge / discharge of 0.1 C with respect to the design capacity 3 Ah of the battery is shown in the column of “0.1 C capacity” in FIG.
- the current was set to 0.3A, and charging was performed at a constant current of 0.3A until reaching 4.2V. After reaching 4.2V, charging was performed at a constant voltage of 4.2V until reaching 0.03A. Thereafter, the battery was discharged at a constant current of 0.3 A until the battery voltage reached 2.8 V, and the obtained discharge capacity was defined as “0.1 C capacity”. Under this condition, since the rate is low, it is desirable to obtain a design capacity. In Example 12 to Example 21, a design capacity of 3 Ah is obtained.
- liquid leakage can be prevented by setting the preferred average pore diameter to 0.05 ⁇ m or more and 0.5 ⁇ m or less. Furthermore, from the results of Examples 7, 8, and 9 used in Examples 18 and 19, 0.1 ⁇ m or more and 0.5 ⁇ m are more advantageous for increasing the battery capacity.
- Comparative Example 1 and Comparative Example 2 are the results of the positive electrode.
- Comparative Example 1 is an example in which no nanofiber was used, and the electrolyte leaked out in the liquid leakage test described above.
- Comparative Example 2 although nanofibers were used, since there were few, there was leakage of electrolyte.
- the method for the electrolyte leakage test is as described above, and the positive electrode used in the comparative example is inserted between two medicine-wrapped papers and a polyethylene porous separator and pressed. The applied pressure was 3 MPa per unit area of the positive electrode.
- Comparative Example 3 and Comparative Example 4 are the results of the negative electrode.
- Comparative Example 1 is an example in which no nanofiber was used, and the electrolyte leaked out in the liquid leakage test described above. The amounts of seepage were 35% (Comparative Example 3) and 10% (Comparative Example 4) with respect to the initial amount of electrolytic solution.
- Comparative Example 2 although nanofibers were used, since there were few, there was leakage of electrolyte. The measurement method is the same as described above.
- the comparative example 5 in FIG. 3 includes the electrode of the comparative example in FIG. 2 (Comparative Example 1 and Comparative Example 3) and the lithium ion secondary battery in FIG. 1 using the semisolid electrolyte of Example 12 as the semisolid electrolyte.
- the result of producing and performing a charge / discharge test is shown. Although the 0.1 C capacity was close to the rated capacity of 3 Ah, the 1 C capacity was significantly lower than the results of Examples 12 to 21. This is probably because the electrolyte retention of the electrode of Comparative Example 1 or Comparative Example 3 was reduced.
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Abstract
Description
図1は、リチウムイオン二次電池101の内部構造を模式的に示している。リチウムイオン二次電池101とは、非水電解質中における電極へのリチウムイオンの吸蔵・放出により、電気エネルギを貯蔵または利用可能とする電気化学デバイスである。これは、リチウムイオン電池、非水電解質二次電池、非水電解液二次電池の別の名称で呼ばれるが、いずれの電池も本発明の対象である。
正極スラリを集電体に塗布した後に、正極スラリの溶媒を乾燥させ、必要に応じて、正極を圧縮成型すれば、正極107が完成する。本発明の電解質を添加する前の正極合剤層の細孔径は、水銀ポロシメータを用いて測定される。その適正な平均細孔径は、0.001μm以上0.5μm以下である。細孔径が小さいため、ナノファイバの保持力に加え、毛細管力による電解質の保持力が増大し、好適である。
負極108は、負極活物質(電極活物質)、バインダ、集電体からなる。負極活物質は、非晶質炭素で被覆した天然黒鉛である。
本実施例では、黒鉛を活物質に用いたが、シリコンやスズまたはそれらの化合物(酸化物、窒化物、および他の金属との合金)を負極活物質に用いてもよい。これらの活物質は、黒鉛の理論容量(372Ah/kg)よりも大きく、500~1500Ah/kgの容量が得られる。これらの高容量材料を用いると、上述の合剤厚さを薄くすることができ、電池の中に収納可能な電極面積を増大させることができる。その結果、電池の抵抗を低下させて高出力が可能になると同時に、黒鉛負極を用いたときよりも電池の容量を高めることができる。
正極107または負極108の細孔に電解質を充填するためには、前述の正極または負極に、電解質を添加し、電極の細孔に吸収させることにより、電解質を保持させることができる。別の方法では、電解質と活物質とバインダを混合したスラリを調製し、電極を集電体上に一緒に塗布しても良い。
電解質には、有機溶媒として式1に示すグライムを用いる。グライムとは、エチレングリコールジメチルエーテルを基本単位とし、その繰り返し数の多い順にモノグライム、ジグライム、トリグライム、テトラグライム、ペンタグライム、ヘキサグライムと呼ばれている。電解質には、イミド塩を用いることができ、その代表例として、Li(NSO2F)2 (LiFSIと略記される。)またはLiN(SO2CF3)2 (LiTFSIと略記される)、LiC4BO8(リチウムビスオキサレートボラート)、CF3SO3Li(トリフルオロメタンスルホン酸リチウム)、LiBF4(ホウフッ化リチウム)が例示される。電解質の濃度は、グライム1リットルに対して、1モル以上3モル以下にすることが好適である。
CH3O-(CH2CH2O)n-CH3 ただし、n=1、2 (式1)
正極107と負極108の間に、半固体電解質からなる電解質層(以下では半固体電解質層109と記す。)を挿入し、電極間のリチウムイオンの授受を可能にする。
本実施例では、半固体電解質層109を形成した正極107と負極108を積層する。図1では、半固体電解質層109は正極107と負極108のいずれの表面に形成されていてもよく、両方の面に形成してもよい。半固体電解質層109は、正極107と負極108の短絡を防止しつつ、リチウムイオンを正極と負極間を移動させる媒体として機能する。
積層体の上部には、正極リード線110および負極リード線111を介して正極外部端子104および負極外部端子105に電気的に接続されている。正極107は正極リード線110を介して蓋103の正極外部端子104に接続されている。負極108は負極リード線111を介して蓋103の負極外部端子105に接続されている。なお、正極リード線110、負極リード線111は、ワイヤ状、板状などの任意の形状を採ることができる。電流を流したときにオーム損失を小さくすることのできる構造であり、かつ電解液と反応しない材質であれば、正極リード線110、負極リード線111の形状、材質は、電池容器102の構造に応じて任意に選択することができる。
電池容器102の材質は、アルミニウム、ステンレス鋼、ニッケルメッキ鋼製など、電解質に対し耐食性のある材料から選択される。
図2に、本発明の電極仕様を例示した。実施例1から実施例8は、正極に本発明を適用した例である。実施例1から実施例3は、カルボキシメチルセルロース(CMC)からなるナノファイバを正極に添加した。繊維径は0.1μm、繊維長は5μmである。ナノファイバの添加量を3重量%から13重量%まで変化させた。作製した正極の平均細孔径は、水銀ポロシメータを用いて測定し、0.4μmから0.05μmの範囲にあった。
比較例1と比較例2は、正極の結果である。比較例1は、ナノファイバを用いなかった例であり、前述の液漏れ試験にて、電解質の染み出しがあった。比較例2では、ナノファイバを用いたものの、それが少ないため、電解質の染み出しがあった。なお、電解質の漏れ試験の方法は、前述の通りであり、比較例に用いた正極を、二枚の薬包紙やポリエチレン多孔質セパレータの間に挿入し、加圧する。加圧力は、正極の単位面積当たり、3MPaとした。薬包紙やポリエチレン多孔質セパレータの重量が増大し、その値は初期の電解液保持量の40%(比較例1)と15%(比較例2)もあった。この結果より、比較例1と2の正極から、液漏れがあることを確認された。
Claims (4)
- 電極活物質および半固体電解質を有するリチウムイオン二次電池用電極であって、
前記半固体電解質は、有機溶媒またはイオン液体およびリチウム塩を有し、
前記リチウムイオン二次電池用電極は、ナノファイバを有し、
前記ナノファイバは、セルロース系またはポリアクリレート系の樹脂であり、
前記ナノファイバの線径が0.01μm以上1μm以下であり、
水銀ポロシメータにより測定された、前記リチウムイオン二次電池用電極から前記イオン液体および前記リチウム塩を除いた電極合剤層の細孔径の平均値が0.001μm以上0.5μm以下であるリチウムイオン二次電池用電極。 - 請求項1のリチウムイオン二次電池用電極であって、
前記ナノファイバは、セルロース系の樹脂であり、
前記ナノファイバは、水酸基をアルキル化したセルロース繊維または酢酸セルロースであるリチウムイオン二次電池用電極。 - 請求項1のリチウムイオン二次電池用電極であって、
前記リチウムイオン二次電池用電極は、炭素繊維を有し、
前記ナノファイバと前記炭素繊維の重量に対して前記炭素繊維の重量組成が1重量%以上90重量%以下であるリチウムイオン二次電池用電極。 - 請求項1のリチウムイオン二次電池用電極を有するリチウムイオン二次電池。
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JP2018133258A (ja) * | 2017-02-16 | 2018-08-23 | 株式会社豊田中央研究所 | 電解質 |
CN110970595A (zh) * | 2018-10-01 | 2020-04-07 | 丰田自动车株式会社 | 负极、电池和负极的制造方法 |
JP2020524359A (ja) * | 2017-05-30 | 2020-08-13 | ナノテク インストゥルメンツ, インコーポレイテッドNanotek Instruments, Inc. | 導電性の変形可能な準固体ポリマー電極を有する形状適合性のアルカリ金属電池 |
WO2023100726A1 (ja) * | 2021-11-30 | 2023-06-08 | 日本ゼオン株式会社 | 非水電解液二次電池用導電材ペースト、非水電解液二次電池負極用スラリー組成物、非水電解液二次電池用負極、および非水電解液二次電池 |
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JP2018133258A (ja) * | 2017-02-16 | 2018-08-23 | 株式会社豊田中央研究所 | 電解質 |
JP7013653B2 (ja) | 2017-02-16 | 2022-02-01 | 株式会社豊田中央研究所 | 電解質 |
JP2020524359A (ja) * | 2017-05-30 | 2020-08-13 | ナノテク インストゥルメンツ, インコーポレイテッドNanotek Instruments, Inc. | 導電性の変形可能な準固体ポリマー電極を有する形状適合性のアルカリ金属電池 |
JP7353983B2 (ja) | 2017-05-30 | 2023-10-02 | ナノテク インストゥルメンツ,インコーポレイテッド | 導電性の変形可能な準固体ポリマー電極を有する形状適合性のアルカリ金属電池 |
CN110970595A (zh) * | 2018-10-01 | 2020-04-07 | 丰田自动车株式会社 | 负极、电池和负极的制造方法 |
JP2020057500A (ja) * | 2018-10-01 | 2020-04-09 | トヨタ自動車株式会社 | 負極、電池、および負極の製造方法 |
US11539048B2 (en) | 2018-10-01 | 2022-12-27 | Toyota Jidosha Kabushiki Kaisha | Negative electrode, battery, and method of producing negative electrode |
CN110970595B (zh) * | 2018-10-01 | 2023-03-28 | 丰田自动车株式会社 | 负极、电池和负极的制造方法 |
WO2023100726A1 (ja) * | 2021-11-30 | 2023-06-08 | 日本ゼオン株式会社 | 非水電解液二次電池用導電材ペースト、非水電解液二次電池負極用スラリー組成物、非水電解液二次電池用負極、および非水電解液二次電池 |
Also Published As
Publication number | Publication date |
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KR20190052104A (ko) | 2019-05-15 |
EP3565031A1 (en) | 2019-11-06 |
EP3565031A4 (en) | 2020-07-15 |
JPWO2018123324A1 (ja) | 2019-07-25 |
CN110050364A (zh) | 2019-07-23 |
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