WO2016181952A1 - 炭素質材料、炭素質材料-活物質複合体、リチウムイオン二次電池用電極材及びリチウムイオン二次電池 - Google Patents
炭素質材料、炭素質材料-活物質複合体、リチウムイオン二次電池用電極材及びリチウムイオン二次電池 Download PDFInfo
- Publication number
- WO2016181952A1 WO2016181952A1 PCT/JP2016/063824 JP2016063824W WO2016181952A1 WO 2016181952 A1 WO2016181952 A1 WO 2016181952A1 JP 2016063824 W JP2016063824 W JP 2016063824W WO 2016181952 A1 WO2016181952 A1 WO 2016181952A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- carbonaceous material
- weight
- secondary battery
- ion secondary
- resin
- Prior art date
Links
Images
Classifications
-
- 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
- H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
- H01M4/624—Electric conductive fillers
- H01M4/625—Carbon or graphite
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B32/00—Carbon; Compounds thereof
- C01B32/05—Preparation or purification of carbon not covered by groups C01B32/15, C01B32/20, C01B32/25, C01B32/30
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
- C01G51/00—Compounds of cobalt
- C01G51/40—Cobaltates
- C01G51/42—Cobaltates containing alkali metals, e.g. LiCoO2
-
- 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
- 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
-
- 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
-
- 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
- H01M4/362—Composites
- H01M4/364—Composites as mixtures
-
- 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
- H01M4/48—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides
- H01M4/52—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of nickel, cobalt or iron
- H01M4/525—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of nickel, cobalt or iron of mixed oxides or hydroxides containing iron, cobalt or nickel for inserting or intercalating light metals, e.g. LiNiO2, LiCoO2 or LiCoOxFy
-
- 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
- H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
- H01M4/621—Binders
- H01M4/622—Binders being polymers
-
- 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
- H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
- H01M4/621—Binders
- H01M4/622—Binders being polymers
- H01M4/623—Binders being polymers fluorinated polymers
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2006/00—Physical properties of inorganic compounds
- C01P2006/40—Electric properties
-
- 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
- H01M2004/021—Physical characteristics, e.g. porosity, surface area
-
- 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
- H01M2004/026—Electrodes composed of, or comprising, active material characterised by the polarity
- H01M2004/028—Positive electrodes
-
- 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 a carbonaceous material, a carbonaceous material-active material composite, an electrode material for a lithium ion secondary battery, and the lithium ion secondary battery.
- Patent Document 1 discloses a composite of a positive electrode active material and graphene as a positive electrode material.
- Patent Documents 2 and 3 below disclose composites of fine particles and partially exfoliated graphite as an anode electrode material.
- a conductive additive is used to supplement the conductivity of the active material.
- a conductive auxiliary agent is used by being mixed with an active material and a binder resin and applied to a current collector. Furthermore, since it is necessary to increase the electrode density in the positive electrode application, it is usually used after being processed by a roll press.
- the active material when graphene as in Patent Document 1 is used as the conductive auxiliary agent, the active material may be peeled off from the current collector when processed by the roll press. Such peeling occurred particularly remarkably when the amount of the binder resin added was small. Therefore, it is necessary to increase the addition amount of the binder resin, and it is difficult to increase the electrode density required for the positive electrode.
- Patent Documents 2 and 3 describe that partially exfoliated exfoliated graphite is used as an electrode of a lithium ion secondary battery. However, its use and effects are only described for application to negative electrode materials.
- An object of the present invention is to provide a carbonaceous material, a carbonaceous material-active material composite, an electrode material for a lithium ion secondary battery, and the carbonaceous material capable of improving initial charge / discharge efficiency and cycle characteristics of the lithium ion secondary battery.
- a lithium ion secondary battery comprising an electrode composed of an active material composite or the electrode material for a lithium ion secondary battery.
- the carbonaceous material according to the present invention is a carbonaceous material used for an electrode material for a lithium ion secondary battery, and a mixture of 5% by weight of the carbonaceous material and 95% by weight of lithium cobaltate at a pressure of 13 MPa.
- the volume resistivity is 0.7 ⁇ ⁇ cm or less.
- the volume resistivity at a pressure of 13 MPa of a mixture of 5% by weight of the carbonaceous material and 95% by weight of the lithium cobaltate is measured, the volume resistivity is measured. Is 0.5 ⁇ ⁇ cm or less.
- the volume resistivity at a pressure of 38 MPa of a mixture of 5% by weight of the carbonaceous material and 95% by weight of the lithium cobaltate is measured, the volume resistance is measured.
- the rate is 0.4 ⁇ ⁇ cm or less.
- the volume resistivity at a pressure of 38 MPa of a mixture of 3% by weight of the carbonaceous material and 97% by weight of lithium cobaltate is measured, the volume resistivity is measured. Is 0.04 ⁇ ⁇ cm or less.
- the volume resistivity at a pressure of 38 MPa of a mixture of 2% by weight of the carbonaceous material and 98% by weight of lithium cobaltate is measured, the volume resistance is measured.
- the rate is 0.1 ⁇ ⁇ cm or less.
- the volume resistivity at a pressure of 38 MPa of a mixture of 1% by weight of the carbonaceous material and 99% by weight of lithium cobaltate is measured, the volume resistance is measured.
- the rate is 5.5 ⁇ ⁇ cm or less.
- the D / G ratio is 0.5 or less.
- a film thickness of a sheet composed of 5% by weight of the carbonaceous material, 92% by weight of lithium cobaltate, and 3% by weight of polyvinylidene fluoride is x ⁇ m, Where y ⁇ 0.1055e 0.0169x (x ⁇ 60) is satisfied, where y ⁇ ⁇ cm is the volume resistivity.
- the carbonaceous material has a BET specific surface area (m 2 / g) of 25 m 2 / g or more and 500 m 2 / g or less.
- the carbonaceous material is obtained by thermally decomposing a resin in a composition in which the resin is fixed to graphite or primary exfoliated graphite by grafting or adsorption. And, it has a structure in which graphite is partially exfoliated.
- the carbonaceous material-active material composite according to the present invention includes a carbonaceous material constituted according to the present invention and an active material.
- the active material is lithium cobalt oxide.
- the content of the carbonaceous material is preferably 0.5% by weight or more and 10% by weight or less.
- the carbonaceous material-active material composite according to the present invention is preferably a positive electrode material for a lithium ion secondary battery.
- the lithium ion secondary battery includes an electrode configured of a carbonaceous material-active material composite configured according to the present invention.
- An electrode material for a lithium ion secondary battery according to the present invention is an electrode material for a lithium ion secondary battery, and includes an active material, a conductive additive containing a carbonaceous material, and a binder resin, and the electrode
- the proportion of the conductive assistant in 100% by weight of the material is 1% by weight or more and 10% by weight or less
- the proportion of the binder resin in 100% by weight of the electrode material is 1% by weight or more and 4% by weight or less.
- the carbon measured based on the difference between the absorbance of a 10 mg / L methylene blue methanol solution and the absorbance of the supernatant obtained by introducing the carbonaceous material into the methylene blue methanol solution and centrifuging.
- the ratio y / x is 0.14 or more
- the BET specific surface area of the carbonaceous material is 25 m 2 / g or more and 500 m 2 / g or less.
- the carbonaceous material is obtained by pyrolyzing a resin in a composition in which the resin is fixed to graphite or primary exfoliated graphite by grafting or adsorption. It is a resin-retained partially exfoliated graphite having a structure in which graphite is partially exfoliated and in which a part of the resin remains.
- the electrode density is relative to the specific gravity of the active material (in the case of LiCoO 2 , the specific gravity is 2.0 to 2.6 g / cm 3 ). 0.8 to 1.5 times (electrode density 1.6 to 3.9 g / cm 3 ).
- the active material is lithium cobalt oxide.
- the binder resin is styrene butadiene rubber, carboxymethyl cellulose, polyvinylidene fluoride, polyimide resin, acrylic resin, butyral resin, and modified products thereof. At least one selected from the group consisting of:
- the electrode material is a positive electrode material for a lithium ion secondary battery.
- the lithium ion secondary battery includes an electrode configured by an electrode material for a lithium ion secondary battery configured according to the present invention.
- a carbonaceous material a carbonaceous material-active material composite, and an electrode material for a lithium ion secondary battery that can improve the initial charge / discharge efficiency and cycle characteristics of the lithium ion secondary battery. it can.
- FIG. 1 is a photograph showing a positive electrode of a lithium ion secondary battery obtained in Example 1.
- FIG. 2 is a photograph showing the positive electrode of the lithium ion secondary battery obtained in Comparative Example 1.
- FIG. 3 is a photograph showing the positive electrode of the lithium ion secondary battery obtained in Comparative Example 2.
- FIG. 4 is a schematic diagram for explaining a method of measuring volume resistivity.
- FIG. 5 is a graph showing the volume resistivity at each pressure of the carbonaceous material-active material composites obtained in the examples and comparative examples.
- FIG. 6 is a diagram showing the volume resistivity of the electrode sheet after roll pressing obtained in Examples and Comparative Examples.
- FIG. 7 is a schematic diagram for explaining a method for measuring the volume resistivity of the electrode sheet.
- FIG. 8 is an exploded perspective view showing a schematic configuration of a lithium ion secondary battery experimental battery produced in Examples and Comparative Examples.
- FIG. 9 is a diagram showing charge / discharge characteristics of lithium ion secondary batteries produced using the positive electrodes obtained in Examples and Comparative Examples.
- FIG. 10 is a relationship diagram in Example 11 and Comparative Example 10 where the horizontal axis represents the positive electrode sheet thickness and the vertical axis represents the volume resistivity of the positive electrode sheet.
- the carbonaceous material of the present invention is a carbonaceous material used for an electrode material for a lithium ion secondary battery.
- the carbonaceous material of the present invention has a volume resistivity of 0.7 ⁇ ⁇ cm when the volume resistivity at a pressure of 13 MPa of a mixture of 5% by weight of the carbonaceous material and 95% by weight of lithium cobaltate is measured. It is as follows.
- volume resistivity under each pressure can be measured.
- volume resistivity can be performed using, for example, a powder resistance device (manufactured by Mitsubishi Chemical Corporation, product number: PD-51).
- the carbonaceous material of the present invention is used as an electrode material of a lithium ion secondary battery, for example, as a conductive additive, the initial charge / discharge efficiency and cycle characteristics of the lithium ion secondary battery can be improved. It can use suitably for the positive electrode material of an ion secondary battery.
- the carbonaceous material of the present invention is a pressure of a mixture of 5% by weight of the carbonaceous material and 95% by weight of lithium cobaltate.
- the volume resistivity at 13 MPa is measured, the volume resistivity is preferably 0.7 ⁇ ⁇ cm or less, more preferably 0.5 ⁇ ⁇ cm or less, and 0.4 ⁇ ⁇ cm or less. More preferably, it is particularly preferably 0.3 ⁇ ⁇ cm or less.
- the volume resistivity at a pressure of 38 MPa is measured, the volume resistivity is preferably 0.4 ⁇ ⁇ cm or less, and more preferably 0.2 ⁇ ⁇ cm or less.
- the volume resistivity at a pressure of 38 MPa of a mixture of 3% by weight of the carbonaceous material and 97% by weight of the lithium cobaltate is measured, the volume resistivity is 0.04 ⁇ ⁇ cm or less. It is preferable. In this case, since the ratio of lithium cobaltate is increased, the capacity can be further increased.
- the volume resistivity is set to be 0.1. It is preferably 1 ⁇ ⁇ cm or less.
- the volume resistivity is 5. It is preferably 5 ⁇ ⁇ cm or less.
- the carbonaceous material has a D / G ratio of 0.5 or less when the peak intensity ratio between the D band and the G band is a D / G ratio in a Raman spectrum obtained by Raman spectroscopy. Is preferred. In this case, the initial charge / discharge efficiency and cycle characteristics of the lithium ion secondary battery can be further improved.
- the film thickness of the sheet composed of 5% by weight of the carbonaceous material, 92% by weight of lithium cobaltate, and 3 parts by weight of polyvinylidene fluoride is x ⁇ m
- the volume resistivity of the sheet is y ⁇ ⁇ cm.
- y ⁇ 0.1055e 0.0169x (x ⁇ 60) is satisfied. In this case, even if the thickness of the sheet is increased, the volume resistivity can be further reduced, so that the thickness of the sheet can be further increased. Therefore, the capacity can be further increased.
- x and y preferably satisfy y ⁇ 0.0786e 0.0153x (x ⁇ 60), and y ⁇ 0.0355e 0.0149x is satisfied. More preferably.
- the carbonaceous material of the present invention preferably has a graphene laminated structure. Further, it is desirable to have a flattened shape that is made into a thin piece.
- the contact point with the active material can be further increased. Therefore, the initial charge / discharge efficiency and cycle characteristics of the lithium ion secondary battery can be further improved.
- Examples of such a carbonaceous material include partially exfoliated exfoliated graphite.
- the partially exfoliated graphite is a pyrolytically prepared composition containing graphite or primary exfoliated graphite and a resin, and the resin is fixed to the graphite or primary exfoliated graphite by grafting or adsorption. is there.
- the resin contained in the composition is preferably removed, but a part of the resin may remain.
- the distance between graphite layers in graphite or primary exfoliated graphite is increased by the above thermal decomposition. Therefore, in the above partially exfoliated graphite, in the graphene laminate, the graphite layer is open from the edge to some extent inside, that is, a part of the graphite is exfoliated, and the graphite layer is the original in the central part. In the same manner as the graphite or primary exfoliated graphite, it has a laminated structure.
- the above partially exfoliated graphite is exfoliated partially by exfoliating graphite at the edge of graphite or primary exfoliated graphite.
- the graphite of the said edge part is a graphene laminated part of a part of edge part in graphite or primary exfoliated graphite.
- the graphite is a laminate of a plurality of graphenes.
- As graphite natural graphite, artificial graphite, expanded graphite and the like can be used. Expanded graphite has a larger graphene layer than normal graphite. Therefore, it peels easily. Therefore, exfoliated graphite can be obtained more easily when expanded graphite is used.
- the graphite has a number of graphene layers of about 100,000 to about 1,000,000 and has a specific surface area (BET specific surface area) by BET of less than 25 m 2 / g.
- the number of graphene layers where the graphite is partially exfoliated and exfoliated is small.
- the number of laminated graphenes in the exfoliated portion is preferably 1000 layers or less, more preferably 100 layers or less, and even more preferably 20 layers or less.
- the initial charge / discharge efficiency and cycle characteristics of the lithium ion secondary battery can be further improved.
- the specific surface area (BET specific surface area) by BET is larger than that of the graphite because the number of graphene layers in the exfoliated portion of the edge portion is small.
- the BET specific surface area of the partially exfoliated graphite is preferably 25 m 2 / g or more, more preferably 500 m 2 / g or less.
- the contact point with the active material can be further enhanced when used as a conductive additive, so the initial charge / discharge efficiency of the lithium ion secondary battery and the cycle The characteristics can be further enhanced.
- primary exfoliated graphite may be used instead of graphite as a raw material.
- the primary exfoliated graphite contains a large amount of exfoliated graphite obtained by exfoliating graphite.
- a composition containing primary exfoliated graphite and a resin, in which the resin is grafted or adsorbed on the primary exfoliated graphite is prepared. Since primary exfoliated graphite is obtained by exfoliating graphite, the specific surface area may be larger than that of graphite.
- exfoliated graphite is a graphene laminate after exfoliation obtained by exfoliating original graphite or primary exfoliated graphite, and has a specific surface area greater than that of the original graphite or primary exfoliated graphite. Or a graphene laminate in which the decomposition end point of the original graphite or primary exfoliated graphite is shifted to lower temperatures.
- the partially exfoliated exfoliated graphite has a structure in which the central part has a graphite structure and the edge part is exfoliated as described above. For this reason, handling is easier than conventional exfoliated graphite.
- the partially exfoliated graphite exfoliated graphite is obtained by producing a resin-retained partially exfoliated graphite in the same manner as the exfoliated graphite / resin composite material described in WO2014 / 034156 A1, and heat treatment to remove excess resin. Can be obtained by removing. However, it may be used without removing the resin, but it is preferable to use it without removing the resin.
- the obtained partially exfoliated exfoliated graphite is superior in conductivity as compared with conventional graphene oxide and graphene obtained by reducing the graphene oxide. This is probably because conventional graphene oxide or redox graphene cannot sufficiently secure the sp 2 structure.
- the partially exfoliated exfoliated graphite can further improve the initial charge / discharge efficiency and cycle characteristics of lithium ion secondary batteries. it can.
- the carbonaceous material-active material composite of the present invention includes the carbonaceous material and an active material.
- the material which acts as a positive electrode in a lithium ion secondary battery can be used suitably.
- Examples of such a material include a layered oxide active material such as lithium cobaltate (LiCoO 2 ), a lithium excess active material, a spinel positive electrode active material such as lithium manganate (LiMn 2 O 4 ), and V 2.
- a metal oxide active material such as O 5 a metal compound active material such as TiS 2 , MoS 2 , and NbSe 2 , or an olivine active material such as lithium iron phosphate and lithium manganese phosphate can be used.
- a layered oxide active material such as lithium cobaltate (LiCoO 2 ) is used. These may be used alone or in combination.
- the content of the carbonaceous material in the carbonaceous material-active material complex is preferably 0.5% by weight or more, and more preferably 10% by weight or less.
- the content of the carbonaceous material is preferably 0.5% by weight or more, and more preferably 10% by weight or less.
- the method for producing the carbonaceous material-active material composite is not particularly limited, and for example, it can be produced by the following method.
- resin residual partially exfoliated graphite is obtained by a method similar to the method for producing exfoliated graphite / resin composite material described in WO2014 / 034156 A1.
- the resin-residual partially exfoliated graphite exfoliated graphite and the active material are dispersed in an adsorption solvent, and the mixture is stirred for a predetermined time to adsorb the active material and the carbonaceous material in the solvent.
- the composite is baked to remove the residual resin. Thereby, a carbonaceous material-active material complex is obtained.
- the adsorption solvent examples include nonpolar solvents such as hexane, toluene, and ethyl acetate, polar aprotic solvents such as tetrahydrofuran (THF) and N, N-dimethylformamide, polar protic solvents such as methanol and ethanol, and the like. At least one kind can be used. Preferably, tetrahydrofuran can be used. When tetrahydrofuran is used, the adsorption of the carbonaceous material and the active material becomes stronger, and the powder resistance of the carbonaceous material-active material composite and the electrode resistance when an electrode is produced using the composite are further increased. Can be reduced.
- nonpolar solvents such as hexane, toluene, and ethyl acetate
- polar aprotic solvents such as tetrahydrofuran (THF) and N, N-dimethylformamide
- polar protic solvents such as methanol and
- the carbonaceous material-active material composite of the present invention includes a carbonaceous material having a volume resistivity within the above-mentioned range, when used as an electrode material for a lithium ion secondary battery, the initial stage of the lithium ion secondary battery The charge / discharge efficiency and cycle characteristics can be effectively enhanced.
- the carbonaceous material-active material composite of the present invention can be suitably used as an electrode material for a lithium ion secondary battery.
- it can be suitably used for a positive electrode material for a lithium ion secondary battery.
- the electrode material for lithium ion secondary batteries according to the present invention is an electrode material for lithium ion secondary batteries.
- the electrode material for a lithium ion secondary battery of the present invention includes an active material, a conductive additive, and a binder resin.
- the conductive auxiliary agent contains a carbonaceous material.
- the content of the conductive assistant in 100% by weight of the electrode material is 1% by weight or more and 10% by weight or less.
- the content of the conductive assistant in 100% by weight of the electrode material is 1% by weight or more and 10% by weight or less.
- the content of the conductive assistant in 100% by weight of the electrode material is preferably 1% by weight or more.
- the amount is preferably 10% by weight or less, more preferably 5% by weight or less, and still more preferably 3% by weight or less.
- the content of the binder resin in 100% by weight of the electrode material is 1% by weight or more and 4% by weight or less.
- an active material may peel from a collector so that it may mention later.
- an electrode density may not fully be raised.
- the content of the binder resin in 100% by weight of the electrode material is preferably 1% by weight or more, more preferably It is 2% by weight or more, preferably 4% by weight or less, more preferably 3% by weight or less.
- the present invention it was measured based on the difference between the absorbance of a 10 mg / L concentration methylene blue methanol solution and the absorbance of the supernatant obtained by centrifuging the carbonaceous material into the methylene blue methanol solution.
- the methylene blue adsorption amount ( ⁇ mol / g) per 1 g of the carbonaceous material is y and the BET specific surface area (m 2 / g) of the carbonaceous material is x
- the ratio y / x is 0.14 or more.
- the BET specific surface area of the carbonaceous material is 25 m 2 / g or more and 500 m 2 / g or less.
- the ratio y / x is 0.14 or more, the specific surface area of the carbonaceous material in the liquid is large. Therefore, the contact area between the carbonaceous material and the active material can be increased in the solvent.
- the BET specific surface area is within the above range, the distance between the graphene layers is reduced in the dry state, and the specific surface area of the carbonaceous material is reduced. Therefore, the amount of binder resin adsorbed on the surface of the carbonaceous material can be suppressed in the step of adding the binder after drying the composite of the carbonaceous material and the active material, resulting in adsorption on the surface of the current collector. Since the amount of binder to be increased can be increased, peeling of the active material from the current collector is suppressed. More specifically, it will be described as follows.
- An electrode material for a lithium ion secondary battery is usually used by coating a current collector such as a metal foil. At this time, in particular, in the positive electrode, since it is required to increase the electrode density, it is further processed by a roll press and used.
- the contact area between the active material and the conductive auxiliary agent can be secured, but at the same time, the amount of binder adsorbed on the surface of the conductive auxiliary agent is increased. As a result, the amount of binder resin that can be adsorbed on the surface of the current collector is reduced. For this reason, if the amount of the binder resin added is small, the amount of the binder resin used to improve the adhesion between the active material or the active material / conducting agent composite and the current collector is insufficient, and is applied by a roll press. The active material may peel from the current collector during the pressure treatment.
- the conductive assistant and the active material are mixed by mixing the conductive assistant and the active material in the liquid.
- the contact area of a substance can be ensured and adhesion can be improved.
- the amount of binder adsorbed on the surface of the conductive auxiliary agent can be suppressed by mixing the composite of the conductive auxiliary agent and the active material with the binder resin in a dry state, and as a result, it can be adsorbed on the surface of the current collector.
- the amount of binder resin will increase. Therefore, even if the amount of binder resin added is small, the amount of binder resin used to improve the adhesion between the active material and the current collector can be secured, and the peeling from the current collector is suppressed. Will be.
- the specific surface area in the dry state is lower than in the liquid. Therefore, unlike graphene, CNT, graphite, and spherical carbon, which have almost the same specific surface area in the liquid and in the dry state, even if the binder resin is added in a small amount, Peeling can be suppressed.
- the active material is hardly separated from the current collector even if the amount of the binder resin added is small. Moreover, since the addition amount of binder resin can be decreased, an electrode density can be raised. Therefore, when the electrode material for a lithium ion secondary battery of the present invention is used as a positive electrode material, the capacity of the lithium ion secondary battery can be increased. From the viewpoint of further increasing the capacity of the lithium ion secondary battery, the electrode density is 0.8 times the specific gravity of the active material (2.0 to 2.6 g / cm 3 in the case of LiCoO 2 ). As described above, it is preferably 1.5 times or less (when the active material is LiCoO 2 , the electrode density is 1.6 to 3.9 g / cm 3 ).
- the active material is not particularly limited, and a material that functions as a positive electrode in a lithium ion secondary battery can be suitably used.
- a material that functions as a positive electrode in a lithium ion secondary battery can be suitably used.
- examples of such a material include a layered oxide active material such as lithium cobaltate (LiCoO 2 ), a lithium excess active material, a spinel positive electrode active material such as lithium manganate (LiMn 2 O 4 ), and V 2.
- a metal oxide active material such as O 5
- a metal compound active material such as TiS 2 , MoS 2 , and NbSe 2
- an olivine active material such as lithium iron phosphate and lithium manganese phosphate can be used. These may be used alone or in combination.
- the conductive auxiliary agent contains a carbonaceous material.
- the carbonaceous material preferably has a graphene stacked structure.
- the carbonaceous material has a ratio y / x of 0.14 or more when the methylene blue adsorption amount ( ⁇ mol / g) measured by the following method is y and the BET specific surface area (m 2 / g) is x.
- the BET specific surface area is preferably 25 m 2 / g or more and 500 m 2 / g or less.
- the ratio y / x is preferably 0.14 or more, and preferably 1.00 or less.
- the BET specific surface area is more preferably 50 m 2 / g or more, more preferably 300 m 2 / g or less, and still more preferably 280 m 2 / g or less.
- the amount of methylene blue adsorbed is the absorbance of a methanol solution of methylene blue at a concentration of 10 mg / L and the absorbance of the supernatant obtained by centrifugation after the carbonaceous material is added to the methanol solution of methylene blue and stirred. Measured based on the difference.
- the methylene blue adsorption amount is determined by the following method.
- the carbonaceous material is charged into a methanol solution of methylene blue having a concentration of 10 mg / L and stirred. Next, the mixture is centrifuged, and the change in absorbance at the maximum absorption wavelength of the obtained supernatant is observed.
- Methylene blue is adsorbed to the portion of the carbonaceous material where graphene is laminated by ⁇ conjugation.
- methylene blue emits fluorescence when irradiated with light. When methylene blue is adsorbed on graphene, it does not emit fluorescence. That is, the fluorescence intensity is reduced. Therefore, the amount of methylene blue adsorbed can be determined from the amount of decrease in the fluorescence intensity obtained from the supernatant with respect to the fluorescence intensity of the original methylene blue.
- the ratio y / x of the carbonaceous material is preferably 0.14 or more.
- the ratio y / x is 0.13. Therefore, when the ratio y / x is 0.14 or more, the conventional spherical graphite has the same BET specific surface area, but the methylene blue adsorption amount increases. That is, in this case, although it is somewhat condensed in the dry state, in the wet state such as in methanol, the graphene layer or the graphite layer can be further expanded compared to the dry state.
- Examples of such a carbonaceous material include resin residual partially exfoliated graphite.
- the resin-retained partially exfoliated graphite comprises graphite or primary exfoliated graphite and a resin, and a composition in which the resin is fixed to the graphite or primary exfoliated graphite by grafting or adsorption is prepared.
- the resin is thermally decomposed while leaving a part of the resin contained therein.
- the resin-retained partially exfoliated graphite exfoliated graphite has a graphite layer open from the edge to some extent inside, that is, a part of the graphite is exfoliated, and a graphite layer is formed in the central part. Similar to the original graphite or primary exfoliated graphite. Resin remaining partially exfoliated graphite is exfoliated partially by exfoliating graphite at the edge of graphite or primary exfoliated graphite.
- the graphite of the said edge part is a graphene laminated part of a part of edge part in graphite or primary exfoliated graphite.
- the thermal decomposition is performed while leaving a part of the resin, a part of the resin fixed to the graphite or primary exfoliated graphite by grafting or adsorption remains. Accordingly, the specific surface area increases significantly in comparison with the specific surface area of the original graphite, particularly in a liquid. Moreover, since some resin remains, the dispersibility with a binder improves and the amount of binders can be reduced. Furthermore, since the residual resin is included, the scattering property is low and the handling is easy despite the large specific surface area.
- the graphite is a laminate of a plurality of graphenes.
- As graphite natural graphite, artificial graphite, expanded graphite and the like can be used. Expanded graphite has a larger graphene layer than normal graphite. Therefore, it peels easily. Therefore, exfoliated graphite can be obtained more easily when expanded graphite is used.
- the graphite has a graphene stack number of about 100,000 to 1,000,000 and a specific surface area (BET specific surface area) by BET of less than 25 m 2 / g.
- the number of laminated graphenes in the part where the graphite is partially exfoliated and exfoliated is small.
- the number of laminated graphenes in the exfoliated portion is preferably 1000 layers or less, more preferably 100 layers or less, and even more preferably 20 layers or less.
- the compatibility with the binder resin can be further enhanced.
- the specific surface area (BET specific surface area) by BET is larger than that of the graphite.
- the BET specific surface area of the resin residual partially exfoliated graphite is preferably 25 m 2 / g or more, and more preferably 500 m 2 / g or less. When the BET specific surface area is within the above range, it is possible to suppress the peeling of the active material from the current collector while further reducing the addition amount of the binder resin.
- primary exfoliated graphite may be used instead of graphite as a raw material.
- the primary exfoliated graphite contains a large amount of exfoliated graphite obtained by exfoliating graphite.
- a composition containing primary exfoliated graphite and a resin, in which the resin is grafted or adsorbed on the primary exfoliated graphite is prepared. Since primary exfoliated graphite is obtained by exfoliating graphite, the specific surface area may be larger than that of graphite.
- exfoliated graphite is a graphene laminate after exfoliation obtained by exfoliating original graphite or primary exfoliated graphite, and has a specific surface area greater than that of the original graphite or primary exfoliated graphite. Or a graphene laminate in which the decomposition end point of the original graphite or primary exfoliated graphite is shifted to lower temperatures.
- the resin fixed to the graphite or primary exfoliated graphite by grafting or adsorption is not particularly limited, but is preferably a polymer of a radical polymerizable monomer.
- the resin may be a copolymer of a plurality of types of radical polymerizable monomers, or may be a homopolymer of one type of radical polymerizable monomer.
- the resin used examples include polypropylene glycol, polyglycidyl methacrylate, polyvinyl acetate, polybutyral, and polyacrylic acid.
- polyglycidyl methacrylate is used.
- polyglycidyl methacrylate is used, the specific surface area of the resin residual partially exfoliated exfoliated graphite under wet condition can be further increased.
- the amount of the resin remaining in the resin-retained partially exfoliated graphite is preferably 5 to 450 parts by weight with respect to 100 parts by weight of the partially exfoliated exfoliated graphite.
- the amount of the remaining resin is more preferably 15 parts by weight to 350 parts by weight, and further preferably 25 parts by weight to 300 parts by weight.
- the resin-residual partially exfoliated graphite is characterized by being relatively difficult to scatter. This is presumably because the polymer (resin) formed by polymerizing the radical polymerizable monomer remains without being completely decomposed in the thermal decomposition step. In other words, the resin located in the part sandwiched between the graphene layers or the exfoliated graphite layers in the resin-exfoliated partially exfoliated graphite is sandwiched between the graphene layers on both sides or the graphite layers. It is considered that it does not decompose completely near the decomposition temperature. Therefore, the resin residual partially exfoliated graphite is easy to handle.
- Resin residual exfoliation type exfoliated graphite has a structure in which the central part has a graphite structure and the edge part is exfoliated as described above. For this reason, handling is easier than conventional exfoliated graphite.
- the resin-residual partially exfoliated graphite exfoliated graphite contains a resin, and therefore has high dispersibility in other resins.
- the other resin is a resin having high affinity with the resin contained in the resin residual partially exfoliated graphite
- the dispersibility of the resin residual partially exfoliated graphite in another resin is more Increased further.
- the resin-residual partially exfoliated graphite exfoliated graphite can be produced by the same method as the method for producing exfoliated graphite / resin composite material described in WO2014 / 034156 A1.
- the resin-retained partially exfoliated graphite is superior in conductivity compared to conventional graphene oxide and graphene obtained by reducing the graphene oxide.
- the conductive auxiliary agent may further contain another conductive auxiliary agent as a carbonaceous material.
- Other conductive aids include ketjen black, acetylene black, carbon nanotube, carbon nanofiber, and graphene.
- the content of the carbonaceous material in the conductive assistant is not particularly limited, but is preferably 10% by weight or more, more preferably 50% by weight or more, in 100% by weight of the conductive assistant. % Or less is preferable.
- content of the said conductive support agent is more than the said minimum and below the said upper limit, peeling from the electrical power collector of an active material can be suppressed further.
- Conductive aid-active material adsorption solvent in the present invention, a conductive auxiliary agent-active material adsorbing solvent may be used in order to enhance the adsorptivity between the active material and the conductive auxiliary agent.
- the adsorption solvent include nonpolar solvents such as hexane, toluene, and ethyl acetate, polar aprotic solvents such as tetrahydrofuran (THF) and N, N-dimethylformamide, polar protic solvents such as methanol and ethanol, and the like. At least one kind can be used.
- tetrahydrofuran can be used. When tetrahydrofuran is used, the adsorption of the conductive additive and the active material becomes strong, and the electrode resistance when used as an electrode can be further reduced.
- Binder resin As the binder resin, polybutyral, polytetrafluoroethylene, styrene butadiene rubber, polyimide resin, acrylic resin, fluoropolymers such as polyvinylidene fluoride, water-soluble carboxymethylcellulose, or modified products thereof can be used. These may be used alone or in combination. Preferably, polytetrafluoroethylene can be used. When polytetrafluoroethylene is used, dispersibility and heat resistance can be further improved.
- a lithium ion secondary battery according to the present invention includes an electrode configured of the carbonaceous material-active material composite or the electrode material for a lithium ion secondary battery.
- the carbonaceous material-active material composite or the electrode material for a lithium ion secondary battery may be used for either the positive electrode or the negative electrode, but is preferably used for the positive electrode.
- the positive electrode used in the lithium ion secondary battery of the present invention is manufactured as follows, for example.
- the above-described active material and conductive aid are dispersed in the conductive aid-active material adsorbing solvent, and the mixture is stirred for a predetermined time to adsorb the active material and conductive aid in the solvent.
- the composite is fired as necessary.
- the resin contained in the resin residual partially exfoliated exfoliated graphite may be removed by the firing treatment. Thereby, a carbonaceous material-active material complex is obtained.
- the obtained composite is mixed with a binder resin to prepare a coating solution.
- a current collector such as a metal foil and dried to produce a positive electrode.
- the produced positive electrode may be used by punching into the electrode shape as it is, but in order to further improve the electrode density, it is usually used by punching into the electrode shape after performing a treatment such as a roll press.
- the carbonaceous material having different specific surface areas in the wet state and the dry state is used as the conductive auxiliary agent, even when a treatment such as a roll press is performed, the current collection of the active material is performed. Detachment from the body hardly occurs. Therefore, since the addition amount of the binder resin can be reduced, the content of the active material is increased in the positive electrode formed by the electrode material for a lithium ion secondary battery of the present invention. Therefore, the capacity of the lithium ion secondary battery of the present invention including the positive electrode is increased.
- the volume resistivity of the carbonaceous material constituting the carbonaceous material-active material composite is within the above specific range, when used as an electrode material for a lithium ion secondary battery, lithium ion The initial charge / discharge efficiency and cycle characteristics of the secondary battery can be effectively enhanced. Therefore, in the lithium ion secondary battery of the present invention including the positive electrode composed of the carbonaceous material-active material composite, the initial charge / discharge efficiency and cycle characteristics are effectively improved.
- NOF Corporation trade name “Marblef G-2050M”
- average molecular weight approximately 200,000
- thermal decomposition start temperature 245 ° C.
- the mixture was irradiated with ultrasonic waves at 100 W and a transmission frequency of 28 kHz for 300 minutes using an ultrasonic treatment device (manufactured by Honda Electronics Co., Ltd.).
- an ultrasonic treatment device manufactured by Honda Electronics Co., Ltd.
- This composition was formed into a sheet having a thickness of 10 to 20 mm by a casting method.
- the obtained sheet was heat-dried at a temperature of 80 ° C. for 2 hours, at a temperature of 110 ° C. for 1 hour, and at a temperature of 150 ° C. for 1 hour.
- the foaming agent was decomposed by heating at a temperature of 230 ° C. for 2 hours, and then a heating process was performed for 30 minutes at a temperature of 430 ° C. Thereby, a part of the polyglycidyl methacrylate was thermally decomposed to obtain a resin residual partially exfoliated graphite. In this resin-retained partially exfoliated graphite, a part of polyglycidyl methacrylate remains.
- the obtained resin residual partially exfoliated graphite exfoliated graphite had a BET specific surface area x of 292 m 2 / g and a methylene blue adsorption amount y of 45.1 ⁇ mol / g.
- the ratio y / x was 0.154.
- the BET specific surface area and the methylene blue adsorption amount were measured by the methods described later.
- the partially exfoliated graphite when the resin residual part is removed is 5% by weight in the electrode weight.
- 15 g of a THF solution containing LiCoO 2 (produced by ALDRICH, trade name “Lithium cobalt (III) oxide)) as an active material so as to be 93 wt% in the electrode weight. Then, it stirred at room temperature for 1 hour, THF was removed by filtration, and it was made to dry in 50 degreeC oven for 2 hours. Next, a baking process was performed at 380 ° C.
- the electrode sheet thus obtained was dried under reduced pressure at 80 ° C. for 12 hours, then heated to 110 ° C. and dried under reduced pressure for 2 hours. After drying, a part of this electrode sheet was punched out in a circular shape so as to have a diameter of 14 mm to obtain a positive electrode of a lithium ion secondary battery before roll press treatment.
- the remaining electrode sheet was roll-pressed under the condition of a temperature of 25 ° C. by an ultra-compact desktop roll press machine manufactured by Hosen Co., Ltd., and then punched into a circle so that the diameter was 14 mm, and after the roll press treatment
- the positive electrode of the lithium ion secondary battery was obtained.
- Example 2 15 g of a THF solution containing a partially exfoliated graphite exfoliated graphite obtained in the same manner as in Example 1 so that the exfoliated graphite partially exfoliated when the resin remaining part is removed is 5% by weight in the electrode weight; , 10 g of a THF solution containing LiCoO 2 as an active material (trade name “Lithium cobalt (III) oxide” manufactured by ALDRICH, Inc.) so as to be 92% by weight of the electrode weight, and polyvinylidene fluoride (Kida) as a binder resin.
- LiCoO 2 active material
- LiCoO 2 trade name “Lithium cobalt (III) oxide” manufactured by ALDRICH, Inc.
- Kida polyvinylidene fluoride
- the positive electrode of the lithium ion secondary battery before and after the roll press treatment was obtained in the same manner as in Example 1 except that Chemical Product, trade name “PVDF # 1100”) was added so as to be 3%
- Example 3 Preparation of resin-retained partially exfoliated graphite
- ADCA manufactured by Eiwa Kasei Kogyo Co., Ltd., trade name “Binihol AC # R”
- -K3 thermal decomposition temperature 210 ° C.
- the raw material composition was irradiated with ultrasonic waves for 5 hours at 100 W and an oscillation frequency of 28 kHz using an ultrasonic treatment apparatus (manufactured by Honda Electronics Co., Ltd.).
- Polypropylene glycol (PPG) was adsorbed on the expanded graphite by ultrasonic treatment. In this way, a composition in which polypropylene glycol was adsorbed on expanded graphite was prepared.
- the composition was molded by a solution casting method, and dried by heating at a drying temperature of 80 ° C. for 2 hours, at 110 ° C. for 1 hour, and at 150 ° C. for 1 hour. Thereafter, the temperature was maintained at 110 ° C. for 1 hour, and further maintained at 230 ° C. for 2 hours. Thereby, the ADCA was thermally decomposed and foamed in the composition.
- the obtained resin residual partially exfoliated graphite exfoliated graphite had a BET specific surface area x of 150 m 2 / g and a methylene blue adsorption amount y of 67.0 ⁇ mol / g.
- the ratio y / x was 0.447.
- the BET specific surface area and the methylene blue adsorption amount were measured by the methods described later.
- Lithium ion secondary battery before and after roll press treatment was performed in the same manner as in Example 2 except that the resin residual partially exfoliated graphite thus obtained was used and the firing treatment conditions were set at 350 ° C. for 2 hours. The positive electrode was obtained.
- ketjen black (trade name “EC300J”, manufactured by Lion Corporation) was used in place of the resin residual partially exfoliated graphite. Further, since no resin remained in the ketjen black, the baking treatment at the time of forming the conductive additive-active material composite was not performed. Except these, it carried out similarly to Example 1, and obtained the positive electrode of the lithium ion secondary battery before and behind a roll press process. In this positive electrode, the contents of the active material, the conductive additive and the binder resin were 93% by weight, 5% by weight and 2% by weight, respectively.
- Ketjen Black had a BET specific surface area x of 800 m 2 / g and a methylene blue adsorption amount y of 98.96 ⁇ mol / g.
- the ratio y / x was 0.124.
- the BET specific surface area and the methylene blue adsorption amount were measured by the methods described later. Electrode density is front roll press roll after pressing was 1.95 g / cm 3 was 2.71 g / cm 3.
- Comparative Example 2 The lithium ion two before and after the roll press treatment were the same as in Comparative Example 1 except that the contents of the active material, conductive additive and binder resin in the positive electrode were respectively set to 92% by weight, 5% by weight and 3% by weight. A positive electrode of a secondary battery was obtained.
- the electrode density roll press after it roll press ago a 2.28 g / cm 3 was 2.98 g / cm 3.
- the active material was not peeled from the current collector after roll pressing.
- the active material was not peeled from the current collector after roll pressing.
- the BET specific surface area was measured using nitrogen gas with a specific surface area measuring device (manufactured by Shimadzu Corporation, product number “ASAP-2000”).
- Methylene blue adsorption amount Methylene blue methanol solutions with concentrations of 10 mg / L, 5.0 mg / L, 2.5 mg / L, and 1.25 mg / L were prepared in a volumetric flask.
- methylene blue special grade reagent methylene blue manufactured by Kanto Chemical Co., Inc. was used.
- UV-visible spectrophotometer product number UV-1600 manufactured by Shimadzu Corporation, the absorbance of the four types of prepared methylene blue solutions was measured to prepare a calibration curve.
- methylene blue was placed in a 50 mL volumetric flask, and methanol was added as a measurement solvent to prepare a 100 mg / L methylene blue solution.
- This methylene blue solution was diluted 10 times with a measurement solvent to obtain a 10 mg / L methylene blue solution.
- the carbonaceous material and the supernatant were separated by centrifugation.
- the absorbance of a blank 10 mg / L methylene blue solution and the absorbance of the supernatant were measured.
- the difference between the absorbance of the blank methylene blue solution and the absorbance of the supernatant, that is, the amount of decrease in absorbance was calculated.
- the amount of decrease in the concentration of the methylene blue solution was determined from the amount of decrease in absorbance and the slope of the calibration curve described above. From the amount of decrease in the concentration of the methylene blue solution, the amount of methylene blue adsorbed on the surface of the carbonaceous material was determined by the following formula.
- Adsorption amount (mol / g) ⁇ Amount of decrease in concentration of methylene blue solution (g / L) ⁇ Volume of measurement solvent (L) ⁇ / ⁇ Molecular blue molecular weight (g / mol) ⁇ Mass of charged carbonaceous material sample ( g) ⁇
- Electrode density The electrode density was determined by the following formula. The results are shown in Table 1 below.
- the mixture was irradiated with ultrasonic waves at 100 W and a transmission frequency of 28 kHz for 300 minutes using an ultrasonic treatment device (manufactured by Honda Electronics Co., Ltd.).
- an ultrasonic treatment device manufactured by Honda Electronics Co., Ltd.
- This composition was formed into a sheet having a thickness of 10 to 20 mm by a casting method.
- the obtained sheet was heat-dried at a temperature of 80 ° C. for 2 hours, at a temperature of 110 ° C. for 1 hour, and at a temperature of 150 ° C. for 1 hour.
- the foaming agent was decomposed by heating at a temperature of 230 ° C. for 2 hours, and then a heating process was performed for 30 minutes at a temperature of 430 ° C. Thereby, a part of the polyglycidyl methacrylate was thermally decomposed to obtain a resin residual partially exfoliated graphite. In this resin-retained partially exfoliated graphite, a part of polyglycidyl methacrylate remains.
- the obtained resin residual partially exfoliated graphite exfoliated graphite had a BET specific surface area x of 292 m 2 / g and a methylene blue adsorption amount y of 45.1 ⁇ mol / g.
- the ratio y / x was 0.154.
- the BET specific surface area and the methylene blue adsorption amount were measured by the above methods.
- a THF solution contained so that the partially exfoliated exfoliated graphite when the resin remaining part was removed from the resin residual partially exfoliated graphite obtained as described above was 5% by weight of the entire composite;
- the mixture was mixed with 10 g of a THF solution containing LiCoO 2 as an active material (trade name “Lithium cobalt (III) oxide” manufactured by ALDRICH, Inc.) so as to be 95% by weight of the entire composite, and then stirred at room temperature for 1 hour.
- the THF was removed by filtration and dried in an oven at 50 ° C. for 2 hours. Next, a calcination treatment at 380 ° C.
- the raw material composition was irradiated with ultrasonic waves for 5 hours at 100 W and an oscillation frequency of 28 kHz using an ultrasonic treatment apparatus (manufactured by Honda Electronics Co., Ltd.).
- Polypropylene glycol (PPG) was adsorbed on the expanded graphite by ultrasonic treatment. In this way, a composition in which polypropylene glycol was adsorbed on expanded graphite was prepared.
- the composition was molded by a solution casting method, and dried by heating at a drying temperature of 80 ° C. for 2 hours, at 110 ° C. for 1 hour, and at 150 ° C. for 1 hour. Thereafter, the temperature was maintained at 110 ° C. for 1 hour, and further maintained at 230 ° C. for 2 hours. Thereby, the ADCA was thermally decomposed and foamed in the composition.
- the obtained resin residual partially exfoliated graphite exfoliated graphite had a BET specific surface area x of 150 m 2 / g and a methylene blue adsorption amount y of 67.0 ⁇ mol / g.
- the ratio y / x was 0.447.
- the BET specific surface area and the methylene blue adsorption amount were measured by the above methods.
- a THF solution contained so that the partially exfoliated exfoliated graphite when the resin remaining part was removed from the resin residual partially exfoliated graphite obtained as described above was 5% by weight of the entire composite;
- the mixture was mixed with 10 g of a THF solution containing LiCoO 2 as an active material (trade name “Lithium cobalt (III) oxide” manufactured by ALDRICH, Inc.) so as to be 95% by weight of the entire composite, and then stirred at room temperature for 1 hour.
- the THF was removed by filtration and dried in an oven at 50 ° C. for 2 hours. Next, a baking treatment at 350 ° C.
- FIG. 5 is a graph showing the volume resistivity at each pressure of the carbonaceous material-active material composites obtained in the examples and comparative examples. Similarly, the volume resistivity at each pressure of the carbonaceous material-active material composites obtained in Examples and Comparative Examples is shown in Table 2 below.
- A shows the result of Example 4
- B shows the result of Example 5
- C shows the result of Comparative Example 3
- D shows the result of Comparative Example 4
- E shows the result of LiCoO 2 alone for comparison.
- Example 5 the volume resistivity at a pressure of 13 MPa is 0.7 ⁇ ⁇ cm or less. In particular, in Example 5, it was 0.1 ⁇ ⁇ cm or less. Furthermore, in Examples 4 and 5, it can be seen that the volume resistivity at a pressure of 38 MPa is 0.2 ⁇ ⁇ cm or less. In particular, in Example 5, it was 0.1 ⁇ ⁇ cm or less.
- the volume resistivity was obtained by measuring the electrical resistance value under a predetermined pressure by a four-probe method using a powder resistance device (manufactured by Mitsubishi Chemical Corporation, product number: PD-51).
- Example 6 15 g of a THF solution containing a partially peeled exfoliated graphite excluding the remaining resin part of the resin remaining partially exfoliated graphite obtained in the same manner as in Example 4 in an amount of 5% by weight of the electrode, The mixture was mixed with 10 g of a THF solution containing LiCoO 2 (produced by ALDRICH, trade name “Lithium cobalt (III) oxide”) as an active material so as to be 92% by weight in the electrode weight, and then stirred at room temperature for 1 hour. The THF was removed by filtration and dried in an oven at 50 ° C. for 2 hours. Next, a baking process was performed at 380 ° C.
- LiCoO 2 produced by ALDRICH, trade name “Lithium cobalt (III) oxide”
- the electrode sheet thus obtained was dried under reduced pressure at 80 ° C. for 12 hours, then heated to 110 ° C. and dried under reduced pressure for 2 hours. After drying, the electrode sheet was roll-pressed under the condition of a temperature of 25 ° C. using an ultra-small desktop roll press machine manufactured by Hosen Co., Ltd. The volume resistivity of the electrode sheet after roll pressing was measured. The results are shown in FIG. Separately, a positive electrode of a lithium ion secondary battery was obtained by punching in a circular shape so that the diameter after roll pressing was 14 mm.
- Example 7 A positive electrode for a lithium ion secondary battery was obtained in the same manner as in Example 6 except that the resin residual partially exfoliated exfoliated graphite produced by the same method as in Example 5 was used.
- FIG. 6 is a diagram showing the volume resistivity of the electrode sheet after roll pressing obtained in Examples 6 and 7 and Comparative Examples 5 and 6. Similarly, the volume resistivity of the electrode sheet after roll pressing obtained in Examples 6 and 7 and Comparative Examples 5 and 6 is shown in Table 3 below.
- the volume resistivity of the electrode sheet was measured using an electrode resistance measuring instrument (manufactured by Hioki Electric Co., Ltd.). Specifically, as shown in FIG. 7, by applying a constant current to the surface of the electrode layer 4 and measuring the potential of the surface of the electrode layer 4 at multiple points, the volume resistivity of the electrode layer 4 and the electrode layer 4 And the electrical resistivity of the current collector 5 were measured.
- Table 3 the electrode density after roll pressing was measured by the method described above.
- Example 6 using the positive electrode of the sheet-like lithium ion secondary battery obtained in Example 6 and Comparative Examples 5 and 6, a lithium ion secondary battery experimental battery was prepared as follows, and the charge / discharge characteristics were evaluated.
- the positive electrode of the lithium ion secondary battery was dried under vacuum at 110 ° C. for 4 hours. After drying, a lithium ion secondary battery experimental battery was produced using this positive electrode in a glove box sprayed with argon gas.
- the structure of the lithium ion secondary battery experimental battery is schematically shown in an exploded perspective view in FIG.
- the negative electrode 8 was a lithium metal piece having a diameter of 16 mm.
- the resin film brand name: Esfino
- 1 mol / L LiBF4 electrolytic solution manufactured by Kishida Chemical Co. was used as the electrolytic solution.
- the voltage was charged from 3.1 V to 4.25 V at a charge rate of 0.05C. The voltage was maintained for 2 hours after reaching 4.25 V, and then rested for 1 minute. Next, the battery was discharged from 4.25V to 3.1V at a discharge rate of 0.05C. After the discharge, it was paused for 1 minute.
- the cycle consisting of the above charging and discharging was repeated 5 times.
- the charge / discharge rate was changed to 0.1 C, and charging and discharging were performed for one cycle.
- the charge / discharge rate was changed to 0.2C, and charging and discharging were performed for one cycle.
- the charge / discharge rate was changed to 0.5C, and the cycle consisting of charging and discharging was repeated 13 times.
- the charge / discharge test results are shown in FIG.
- the horizontal axis represents the number of charge / discharge cycles
- the vertical axis represents the capacity per positive electrode active material (mAhg ⁇ 1 ), that is, the charge / discharge characteristics.
- the solid line indicates the charging characteristics
- the broken line indicates the discharging characteristics.
- Example 6 compared with Comparative Examples 5 and 6, it was confirmed that the initial charge / discharge efficiency and cycle characteristics of the lithium ion secondary battery were enhanced.
- Example 8 15 g of a THF solution containing 3 wt% of the partially exfoliated graphite when the resin remaining portion was removed from the resin residual partially exfoliated graphite produced in the same manner as in Example 1, The mixture was mixed with 10 g of a THF solution containing LiCoO 2 (produced by ALDRICH, trade name “Lithium cobalt (III) oxide”) as an active material so as to be 97 wt% in the electrode weight, and stirred at room temperature for 1 hour. The THF was removed by filtration and dried in an oven at 50 ° C. for 2 hours. Next, a baking process was performed at 380 ° C. for 2 hours to remove the resin remaining part contained in the resin residual partially exfoliated graphite, and a composite of partially exfoliated exfoliated graphite and LiCoO 2 as an active material was obtained. .
- LiCoO 2 produced by ALDRICH, trade name “Lithium cobalt (III) oxide”
- Example 9 15 g of a THF solution containing the partially exfoliated graphite exfoliated graphite obtained in the same manner as in Example 1 so that the exfoliated graphite partially exfoliated when the residual resin part was removed was 2% by weight of the electrode, And 10 g of a THF solution containing LiCoO 2 (product name “Lithium cobalt (III) oxide” manufactured by ALDRICH, Inc.) as an active material so as to be 98 wt% in the electrode weight, and then stirred at room temperature for 1 hour. The THF was removed by filtration and dried in an oven at 50 ° C. for 2 hours. Next, a baking process was performed at 380 ° C. for 2 hours to remove the resin remaining part contained in the resin residual partially exfoliated graphite, and a composite of partially exfoliated exfoliated graphite and LiCoO 2 as an active material was obtained. .
- LiCoO 2 product name “Lithium cobalt (III) oxide” manufactured by ALDRICH, Inc.
- Example 10 15 g of a THF solution containing 1 part by weight of the partially exfoliated graphite exfoliated graphite when the resin residual part was removed from the resin residual partly exfoliated graphite produced in the same manner as in Example 1; The mixture was mixed with 10 g of a THF solution containing LiCoO 2 (produced by ALDRICH, trade name “Lithium cobalt (III) oxide”) as an active material so as to be 99% by weight in the electrode weight, and stirred at room temperature for 1 hour. The THF was removed by filtration and dried in an oven at 50 ° C. for 2 hours. Next, a baking process was performed at 380 ° C. for 2 hours to remove the resin remaining part contained in the resin residual partially exfoliated graphite, and a composite of partially exfoliated exfoliated graphite and LiCoO 2 as an active material was obtained. .
- LiCoO 2 produced by ALDRICH, trade name “Lithium cobalt (III) oxide”
- a conductive additive carbonaceous material
- acetylene black trade name “Li400”, manufactured by Denki Kagaku Kogyo Co., Ltd.
- the baking treatment at the time of forming the conductive additive-active material composite was not performed.
- a conductive assistant-active material composite for a lithium ion secondary battery was obtained in the same manner as in Example 4. In this composite, the contents of the active material and the conductive assistant were 95% by weight and 5% by weight, respectively.
- acetylene black (trade name “Li400”, manufactured by Denki Kagaku Kogyo Co., Ltd.) was used in place of the resin residual partially exfoliated graphite.
- the baking treatment at the time of forming the conductive additive-active material composite was not performed.
- a conductive assistant-active material composite for a lithium ion secondary battery was obtained in the same manner as in Example 8. In this composite, the contents of the active material and the conductive assistant were 97% by weight and 3% by weight, respectively.
- Example 9 As a conductive additive (carbonaceous material), acetylene black (trade name “Li400”, manufactured by Denki Kagaku Kogyo Co., Ltd.) was used in place of the resin residual partially exfoliated graphite. In addition, since no resin remained in acetylene black, the baking treatment at the time of forming the conductive additive-active material composite was not performed. Except for these, a conductive assistant-active material composite for a lithium ion secondary battery was obtained in the same manner as in Example 10. In this composite, the contents of the active material and the conductive assistant were 99% by weight and 1% by weight, respectively. Table 4 shows the volume resistivity at 38 MPa of the conductive additive-active material composites of Examples 8 to 10 and Comparative Examples 7 to 9.
- Example 11 15 g of a THF solution containing a partially exfoliated graphite exfoliated graphite obtained in the same manner as in Example 1 so that the exfoliated graphite partially exfoliated when the resin remaining part is removed is 5% by weight in the electrode weight; The mixture was mixed with 10 g of a THF solution containing LiCoO 2 (produced by ALDRICH, trade name “Lithium cobalt (III) oxide”) as an active material so as to be 92% by weight in the electrode weight, and stirred at room temperature for 1 hour. The THF was removed by filtration and dried in an oven at 50 ° C. for 2 hours. Next, a baking process was performed at 380 ° C.
- LiCoO 2 produced by ALDRICH, trade name “Lithium cobalt (III) oxide
- acetylene black (trade name “Li400”, manufactured by Denki Kagaku Kogyo Co., Ltd.) was used in place of the resin residual partially exfoliated graphite. In addition, since no resin remained in acetylene black, the baking treatment at the time of forming the conductive additive-active material composite was not performed. In this positive electrode, the contents of the active material, the conductive additive and the binder resin (polyvinylidene fluoride) were 92% by weight, 5% by weight and 3% by weight, respectively.
- Example 2 Except for this, roll press treatment was performed in the same manner as in Example 1 so that the positive electrode sheet thickness was 60 ⁇ m, 90 ⁇ m, and 120 ⁇ m (including the aluminum foil of the current collector foil), and the positive electrode of the lithium ion secondary battery ( A positive electrode sheet) was obtained.
- FIG. 10 is a relationship diagram in Example 11 and Comparative Example 10 where the horizontal axis represents the positive electrode sheet thickness and the vertical axis represents the volume resistivity of the positive electrode sheet. As shown in FIG. 10, it was confirmed in Example 11 that the increase in volume resistance accompanying the increase in film thickness was suppressed.
- y ⁇ 0.1055e 0.0169x (x ⁇ 60) is satisfied, and y ⁇ 0.0786e 0.0153x (x ⁇ 60) is more preferable, and y ⁇ 0.0355e 0.0149x is more preferable.
Abstract
Description
本発明の炭素質材料は、リチウムイオン二次電池用の電極材料に用いられる炭素質材料である。また、本発明の炭素質材料は、上記炭素質材料5重量%と、コバルト酸リチウム95重量%との混合物の圧力13MPaにおける体積抵抗率を測定したときに、体積抵抗率が0.7Ω・cm以下である。
本発明の炭素質材料-活物質複合体は、上記炭素質材料と、活物質とを含む。上記活物質としては、特に限定されないが、リチウムイオン二次電池において正極として作用する材料を好適に用いることができる。このような材料としては、例えば、コバルト酸リチウム(LiCoO2)などの層状酸化物系活物質、リチウム過剰系活物質、マンガン酸リチウム(LiMn2O4)などのスピネル型正極活物質、V2O5等の金属酸化物活物質やTiS2、MoS2、NbSe2などの金属化合物系活物質、又は、リン酸鉄リチウム、リン酸マンガンリチウムなどのオリビン系活物質を用いることができる。好ましくは、コバルト酸リチウム(LiCoO2)などの層状酸化物系活物質が用いられる。これらは、単独で用いてもよく、複数を併用してもよい。
本発明に係るリチウムイオン二次電池用電極材は、リチウムイオン二次電池用の電極材料である。本発明のリチウムイオン二次電池用電極材は、活物質と、導電助剤と、バインダー樹脂とを含む。上記導電助剤は、炭素質材料を含有する。
上記活物質としては、特に限定されず、リチウムイオン二次電池において正極として作用する材料を好適に用いることができる。このような材料としては、例えば、コバルト酸リチウム(LiCoO2)などの層状酸化物系活物質、リチウム過剰系活物質、マンガン酸リチウム(LiMn2O4)などのスピネル型正極活物質、V2O5等の金属酸化物活物質やTiS2、MoS2、NbSe2などの金属化合物系活物質、又は、リン酸鉄リチウム、リン酸マンガンリチウムなどのオリビン系活物質を用いることができる。これらは、単独で用いてもよく、複数を併用してもよい。
上記導電助剤は、炭素質材料を含んでいる。上記炭素質材料は、グラフェン積層構造を有していることが好ましい。
本発明においては、上記活物質と、導電助剤との吸着性を高めるために、導電助剤-活物質吸着用溶媒を用いてもよい。上記吸着用溶媒としては、ヘキサンやトルエン、酢酸エチルなどの無極性溶媒や、テトラヒドロフラン(THF)、N,N-ジメチルホルムアミドなどの極性非プロトン性溶媒や、メタノールやエタノールなどの極性プロトン性溶媒などから少なくとも1種類を用いることができる。好ましくは、テトラヒドロフランを用いることができる。テトラヒドロフランを用いた場合、導電助剤と活物質の吸着が強くなり、電極にした時の電極抵抗をより一層低下させることができる。
上記バインダー樹脂としては、ポリブチラール、ポリテトラフルオロエチレン、スチレンブタジエンゴム、ポリイミド樹脂、アクリル樹脂、ポリフッ化ビニリデンなどのフッ素系ポリマー、水溶性のカルボキシメチルセルロース又はこれらの変性物などを用いることができる。これらは、単独で用いてもよく、複数を併用してもよい。好ましくは、ポリテトラフルオロエチレンを用いることができる。ポリテトラフルオロエチレンを用いた場合、分散性や耐熱性をより一層向上させることができる。
本発明に係るリチウムイオン二次電池は、上記炭素質材料-活物質複合体又は上記リチウムイオン二次電池用電極材により構成されている電極を備える。上記炭素質材料-活物質複合体又は上記リチウムイオン二次電池用電極材は、正極又は負極のいずれに用いてもよいが、正極に用いられることが好ましい。
(樹脂残存部分剥離型薄片化黒鉛の調製)
ポリグリシジルメタクリレート(日油株式会社製、商品名「マーブルーフG-2050M」、平均分子量=約20万、熱分解開始温度=245℃)50gをテトラヒドロフラン450gに溶解し、ポリグリシジルメタクリレートの10重量%溶液を得た。このポリグリシジルメタクリレート溶液に、膨張化黒鉛(東洋炭素社製、商品名「PFパウダー8F」)2.5g及び化学発泡剤(永和化成工業社製、商品名「ビニホール AC#R-K3」)5.0gを添加し混合物とした。
実施例1と同様にして作製した樹脂残存部分剥離型薄片化黒鉛のうち樹脂残存部分を除いたときの部分剥離型薄片化黒鉛が電極重量中5重量%となるように含有したTHF溶液15gと、活物質としてのLiCoO2(ALDRICH社製、商品名「Lithium cobalt(III)oxide」)を電極重量中92重量%となるように含有したTHF溶液10gと、バインダー樹脂としてのポリフッ化ビニリデン(キシダ化学株式会社製、商品名「PVDF #1100」)を電極重量中3重量%となるように加えたこと以外は実施例1と同様にしてロールプレス処理前後のリチウムイオン二次電池の正極を得た。
(樹脂残存型部分剥離型薄片化黒鉛の調製)
膨張化黒鉛(東洋炭素社製、商品名「PFパウダー8F」、BET表面積=22m2/g)10gと、熱分解性発泡剤として、ADCA(永和化成工業社製、商品名「ビニホール AC#R-K3」、熱分解温度210℃)20gと、ポリプロピレングリコール(三洋化成工業社製、サンニックスGP-3000、平均分子量=3000)200gと、溶媒としてのテトラヒドロフラン200gとを混合し、原料組成物を用意した。原料組成物に、超音波処理装置(本多電子社製)を用い、100W、発振周波数:28kHzで5時間超音波を照射した。超音波処理により、ポリプロピレングリコール(PPG)を膨張化黒鉛に吸着させた。このようにして、ポリプロピレングリコールが膨張化黒鉛に吸着されている組成物を用意した。
導電助剤(炭素質材料)として樹脂残存部分剥離型薄片化黒鉛の代わりに、ケッチェンブラック(ライオン社製、商品名「EC300J」)を用いた。また、ケッチェンブラックには樹脂が残存しないため、導電助剤-活物質複合体形成時の焼成処理は行わなかった。これら以外は、実施例1と同様にしてロールプレス処理前後のリチウムイオン二次電池の正極を得た。この正極は活物質と導電助剤とバインダー樹脂の含有量がそれぞれ順に93重量%、5重量%、2重量%であった。ケッチェンブラックのBET比表面積xは、800m2/gであり、メチレンブルー吸着量yは、98.96μモル/gであった。また、比y/xは、0.124であった。なお、BET比表面積及びメチレンブルー吸着量は、後述する方法により測定した。電極密度はロールプレス前は1.95g/cm3でありロールプレス後が2.71g/cm3であった。
正極中の活物質と導電助剤とバインダー樹脂の含有量をそれぞれ順に92重量%、5重量%、3重量%としたこと以外は、比較例1と同様にしてロールプレス処理前後のリチウムイオン二次電池の正極を得た。なお、電極密度はロールプレス前が2.28g/cm3でありロールプレス後が2.98g/cm3であった。
実施例及び比較例において、BET比表面積、メチレンブルー吸着量及び電極密度は、以下のようにして測定した。
BET比表面積は、比表面積測定装置(島津製作所社製、品番「ASAP-2000」)により窒素ガスを用いて測定した。
メスフラスコに、10mg/L、5.0mg/L、2.5mg/L、1.25mg/Lの濃度のメチレンブルーのメタノール溶液を調製した。メチレンブルーとしては、関東化学社製特級試薬のメチレンブルーを用いた。島津製作所社製、紫外可視分光光度計(品番UV-1600)を用い、用意した上記4種類のメチレンブルー溶液の吸光度を測定し、検量線を作成した。
電極密度は、以下の式により求めた。結果を下記の表1に示す。
実施例1~3及び比較例1,2の結果の詳細を下記の表1に示す。
ポリグリシジルメタクリレート(日油株式会社製、商品名「マーブルーフG-2050M」、平均分子量=約20万、熱分解開始温度=245℃)50gをテトラヒドロフラン450gに溶解し、ポリグリシジルメタクリレートの10重量%溶液を得た。このポリグリシジルメタクリレート溶液に、膨張化黒鉛(東洋炭素社製、商品名「PFパウダー8F」)2.5g及び化学発泡剤(永和化成工業社製、商品名「ビニホール AC#R-K3」)5.0gを添加し混合物とした。
膨張化黒鉛(東洋炭素社製、商品名「PFパウダー8F」、BET表面積=22m2/g)10gと、熱分解性発泡剤として、ADCA(永和化成工業社製、商品名「ビニホール AC#R-K3」、熱分解温度210℃)20gと、ポリプロピレングリコール(三洋化成工業社製、サンニックスGP-3000、平均分子量=3000)200gと、溶媒としてのテトラヒドロフラン200gとを混合し、原料組成物を用意した。原料組成物に、超音波処理装置(本多電子社製)を用い、100W、発振周波数:28kHzで5時間超音波を照射した。超音波処理により、ポリプロピレングリコール(PPG)を膨張化黒鉛に吸着させた。このようにして、ポリプロピレングリコールが膨張化黒鉛に吸着されている組成物を用意した。
樹脂残存部分剥離型薄片化黒鉛の代わりに、ケッチェンブラック(ライオン社製、商品名「EC300J」)を用いた。また、ケッチェンブラックには樹脂が残存しないため、炭素質材料-活物質複合体形成時の焼成処理は行わなかった。これら以外は、実施例4と同様にして下記の表2に示す組成の炭素質材料-活物質複合体を得た。
樹脂残存部分剥離型薄片化黒鉛の代わりに、導電助剤としてケッチェンブラック(ライオン社製、商品名「EC300J」)80重量%と繊維状カーボン(昭和電工社製、商品名「VGCF-H」)20重量%との混合物を用いた。また、混合物には樹脂が残存しないため、炭素質材料-活物質複合体形成時の焼成処理は行わなかった。これら以外は、実施例4と同様にして下記の表2に示す組成の炭素質材料-活物質複合体を得た。
実施例4と同様にして得られた樹脂残存部分剥離型薄片化黒鉛のうち樹脂残存部分を除いた部分剥離型薄片化黒鉛が電極重量中5重量%となるように含有したTHF溶液15gと、活物質としてのLiCoO2(ALDRICH社製、商品名「Lithium cobalt(III)oxide」)を電極重量中92重量%となるように含有したTHF溶液10gとを混合後、室温で1時間撹拌し、濾過によりTHFを除去し、50℃のオーブンで2時間乾燥させた。次に380℃で2時間の焼成処理を行い、樹脂残存部分剥離型薄片化黒鉛に含まれる樹脂残存部分を除去し、部分剥離型薄片化黒鉛と活物質としてのLiCoO2の複合体を得た。この部分剥離型薄片化黒鉛と活物質の複合体にバインダー樹脂としてのポリフッ化ビニリデン(キシダ化学株式会社製、商品名「PVDF #1100」)を電極重量中3重量%となるように加え、乳鉢で混練した。混練後、NMPを適宜添加して塗工が可能な粘度に希釈調製を行い、塗工液を作製した。作製した塗工液を9milに設定したアプリケータで集電体としてのCu箔に塗工して、集電体上に電極層を有する電極シートを作製した。
実施例5と同様の方法で作製した樹脂残存部分剥離型薄片化黒鉛を用いたこと以外は、実施例6と同様にしてリチウムイオン二次電池の正極を得た。
樹脂残存部分剥離型薄片化黒鉛の代わりに、ケッチェンブラック(ライオン社製、商品名「EC300J」)を用いた。また、ケッチェンブラックには樹脂が残存しないため、炭素質材料-活物質複合体形成時の焼成処理は行わなかった。これら以外は、実施例6と同様にしてリチウムイオン二次電池の正極を得た。
樹脂残存部分剥離型薄片化黒鉛の代わりに、ケッチェンブラック(ライオン社製、商品名「EC300J」)80重量%と繊維状カーボン(昭和電工社製、商品名「VGCF-H」)20重量%との混合物を用いた。また、上記混合物には樹脂が残存しないため、炭素質材料-活物質複合体形成時の焼成処理は行わなかった。なお、炭素質材料-活物質複合体の組成は、下記の表3に示す通りである。これら以外は、実施例6と同様にしてリチウムイオン二次電池の正極を得た。
実施例1と同様にして作製した樹脂残存部分剥離型薄片化黒鉛のうち樹脂残存部分を除いたときの部分剥離型薄片化黒鉛が電極重量中3重量%となるように含有したTHF溶液15gと、活物質としてのLiCoO2(ALDRICH社製、商品名「Lithium cobalt(III)oxide」)を電極重量中97重量%となるように含有したTHF溶液10gとを混合後、室温で1時間撹拌し、濾過によりTHFを除去し、50℃のオーブンで2時間乾燥させた。次に380℃で2時間の焼成処理を行い、樹脂残存部分剥離型薄片化黒鉛に含まれる樹脂残存部分を除去し、部分剥離型薄片化黒鉛と活物質としてのLiCoO2の複合体を得た。
実施例1と同様にして作製した樹脂残存部分剥離型薄片化黒鉛のうち樹脂残存部分を除いたときの部分剥離型薄片化黒鉛が電極重量中2重量%となるように含有したTHF溶液15gと、活物質としてのLiCoO2(ALDRICH社製、商品名「Lithium cobalt(III)oxide」)を電極重量中98重量%となるように含有したTHF溶液10gとを混合後、室温で1時間撹拌し、濾過によりTHFを除去し、50℃のオーブンで2時間乾燥させた。次に380℃で2時間の焼成処理を行い、樹脂残存部分剥離型薄片化黒鉛に含まれる樹脂残存部分を除去し、部分剥離型薄片化黒鉛と活物質としてのLiCoO2の複合体を得た。
実施例1と同様にして作製した樹脂残存部分剥離型薄片化黒鉛のうち樹脂残存部分を除いたときの部分剥離型薄片化黒鉛が電極重量中1重量%となるように含有したTHF溶液15gと、活物質としてのLiCoO2(ALDRICH社製、商品名「Lithium cobalt(III)oxide」)を電極重量中99重量%となるように含有したTHF溶液10gとを混合後、室温で1時間撹拌し、濾過によりTHFを除去し、50℃のオーブンで2時間乾燥させた。次に380℃で2時間の焼成処理を行い、樹脂残存部分剥離型薄片化黒鉛に含まれる樹脂残存部分を除去し、部分剥離型薄片化黒鉛と活物質としてのLiCoO2の複合体を得た。
導電助剤(炭素質材料)として樹脂残存部分剥離型薄片化黒鉛の代わりに、アセチレンブラック(電気化学工業株式会社製、商品名「Li400」)を用いた。また、アセチレンブラックには樹脂が残存しないため、導電助剤-活物質複合体形成時の焼成処理は行わなかった。これら以外は、実施例4と同様にしてリチウムイオン二次電池の導電助剤-活物質複合体を得た。この複合体は活物質と導電助剤の含有量がそれぞれ95重量%、5重量%であった。
導電助剤(炭素質材料)として樹脂残存部分剥離型薄片化黒鉛の代わりに、アセチレンブラック(電気化学工業株式会社製、商品名「Li400」)を用いた。また、アセチレンブラックには樹脂が残存しないため、導電助剤-活物質複合体形成時の焼成処理は行わなかった。これら以外は、実施例8と同様にしてリチウムイオン二次電池の導電助剤-活物質複合体を得た。この複合体は活物質と導電助剤の含有量がそれぞれ97重量%、3重量%であった。
導電助剤(炭素質材料)として樹脂残存部分剥離型薄片化黒鉛の代わりに、アセチレンブラック(電気化学工業株式会社製、商品名「Li400」)を用いた。また、アセチレンブラックには樹脂が残存しないため、導電助剤-活物質複合体形成時の焼成処理は行わなかった。これら以外は、実施例10と同様にしてリチウムイオン二次電池の導電助剤-活物質複合体を得た。この複合体は活物質と導電助剤の含有量がそれぞれ99重量%、1重量%であった。
表4に、実施例8~10及び比較例7~9の導電助剤-活物質複合体の圧力38MPaにおける体積抵抗率を示す。
実施例1と同様にして作製した樹脂残存部分剥離型薄片化黒鉛のうち樹脂残存部分を除いたときの部分剥離型薄片化黒鉛が電極重量中5重量%となるように含有したTHF溶液15gと、活物質としてのLiCoO2(ALDRICH社製、商品名「Lithium cobalt(III)oxide」)を電極重量中92重量%となるように含有したTHF溶液10gとを混合後、室温で1時間撹拌し、濾過によりTHFを除去し、50℃のオーブンで2時間乾燥させた。次に380℃で2時間の焼成処理を行い、樹脂残存部分剥離型薄片化黒鉛に含まれる樹脂残存部分を除去し、部分剥離型薄片化黒鉛と活物質としてのLiCoO2の複合体を得た。この部分剥離型薄片化黒鉛と活物質の複合体にバインダー樹脂としてのポリフッ化ビニリデン(キシダ化学株式会社製、商品名「PVDF #1100」)を電極重量中3重量%となるように加えたこと以外は実施例1と同様にして正極シート膜厚が60μm、90μm、及び120μm(集電箔のアルミニウム箔20μmを含む)になるようにロールプレス処理を行いリチウムイオン二次電池の正極(正極シート)を得た。
導電助剤(炭素質材料)として樹脂残存部分剥離型薄片化黒鉛の代わりに、アセチレンブラック(電気化学工業株式会社製、商品名「Li400」)を用いた。また、アセチレンブラックには樹脂が残存しないため、導電助剤-活物質複合体形成時の焼成処理は行わなかった。この正極は活物質と導電助剤とバインダー樹脂(ポリフッ化ビニリデン)の含有量がそれぞれ順に92重量%、5重量%、3重量%であった。これ以外は、実施例1と同様にして正極シート膜厚が60μm、90μm、及び120μm(集電箔のアルミニウム箔20μmを含む)になるようにロールプレス処理を行いリチウムイオン二次電池の正極(正極シート)を得た。
2…試料
3…電極
4…電極層
5…集電体
6…負極ボディ
7…正極ボディ
8…負極
9…セパレータ
10…電極ガイド
11…正極
12…電極押さえ
13…スプリング
Claims (22)
- リチウムイオン二次電池用の電極材料に用いられる炭素質材料であって、
前記炭素質材料5重量%と、コバルト酸リチウム95重量%との混合物の圧力13MPaにおける体積抵抗率を測定したときに、前記体積抵抗率が0.7Ω・cm以下である、炭素質材料。 - 前記炭素質材料5重量%と、前記コバルト酸リチウム95重量%との混合物の圧力13MPaにおける体積抵抗率を測定したときに、前記体積抵抗率が0.5Ω・cm以下である、請求項1に記載の炭素質材料。
- 前記炭素質材料5重量%と、前記コバルト酸リチウム95重量%との混合物の圧力38MPaにおける体積抵抗率を測定したときに、前記体積抵抗率が0.4Ω・cm以下である、請求項1又は2に記載の炭素質材料。
- 前記炭素質材料3重量%と、コバルト酸リチウム97重量%との混合物の圧力38MPaにおける体積抵抗率を測定したときに、前記体積抵抗率が0.04Ω・cm以下である、請求項1~3のいずれか1項に記載の炭素質材料。
- 前記炭素質材料2重量%と、コバルト酸リチウム98重量%との混合物の圧力38MPaにおける体積抵抗率を測定したときに、前記体積抵抗率が0.1Ω・cm以下である、請求項1~4のいずれか1項に記載の炭素質材料。
- 前記炭素質材料1重量%と、コバルト酸リチウム99重量%との混合物の圧力38MPaにおける体積抵抗率を測定したときに、前記体積抵抗率が5.5Ω・cm以下である、請求項1~5のいずれか1項に記載の炭素質材料。
- ラマン分光法によって得られるラマンスペクトルにおいて、Dバンドと、Gバンドとのピーク強度比をD/G比としたときに、D/G比が、0.5以下である、請求項1~6のいずれか1項に記載の炭素質材料。
- 前記炭素質材料5重量%、コバルト酸リチウム92重量%、及びポリフッ化ビニリデン3重量%からなるシートの膜厚をxμmとし、前記シートの体積抵抗率をyΩ・cmとしたときに、y<0.1055e0.0169x(x≧60)を満たしている、請求項1~7のいずれか1項に記載の炭素質材料。
- 前記炭素質材料のBET比表面積(m2/g)が、25m2/g以上、500m2/g以下である、請求項1~8のいずれか1項に記載の炭素質材料。
- 前記炭素質材料は、樹脂が黒鉛又は一次薄片化黒鉛にグラフト又は吸着により固定されている組成物中の樹脂を熱分解したものであって、部分的にグラファイトが剥離されている構造を有する、請求項1~9のいずれか1項に記載の炭素質材料。
- 請求項1~10のいずれか1項に記載の炭素質材料と、活物質とを含む、炭素質材料-活物質複合体。
- 前記活物質が、コバルト酸リチウムである、請求項11に記載の炭素質材料-活物質複合体。
- 前記炭素質材料の含有量が、0.5重量%以上、10重量%以下である、請求項11又は12に記載の炭素質材料-活物質複合体。
- リチウムイオン二次電池用の正極材料である、請求項11~13のいずれか1項に記載の炭素質材料-活物質複合体。
- 請求項11~14のいずれか1項に記載の炭素質材料-活物質複合体により構成されている電極を備える、リチウムイオン二次電池。
- リチウムイオン二次電池用の電極材料であって、
活物質と、炭素質材料を含有する導電助剤と、バインダー樹脂とを含み、
前記電極材料100重量%中の前記導電助剤の割合が、1重量%以上、10重量%以下であり、
前記電極材料100重量%中の前記バインダー樹脂の割合が、1重量%以上、4重量%以下であり、
10mg/L濃度のメチレンブルーのメタノール溶液の吸光度と、該メチレンブルーのメタノール溶液に前記炭素質材料を投入し、遠心分離により得られた上澄み液の吸光度との差に基づき測定された前記炭素質材料1gあたりのメチレンブルー吸着量(μモル/g)をy、前記炭素質材料のBET比表面積(m2/g)をxとした場合、比y/xが0.14以上であり、且つ炭素質材料のBET比表面積が、25m2/g以上、500m2/g以下である、リチウムイオン二次電池用電極材。 - 前記炭素質材料は、樹脂が黒鉛又は一次薄片化黒鉛にグラフト又は吸着により固定されている組成物中の樹脂を熱分解したものであって、部分的にグラファイトが剥離されている構造を有し、かつ前記樹脂が一部残存している樹脂残存部分剥離型薄片化黒鉛である、請求項16に記載のリチウムイオン二次電池用電極材。
- 電極密度が、前記活物質の比重に対して、0.8倍以上、1.5倍以下である、請求項16又は17に記載のリチウムイオン二次電池用電極材。
- 前記活物質が、コバルト酸リチウムである、請求項16~18のいずれか1項に記載のリチウムイオン二次電池用電極材。
- 前記バインダー樹脂が、スチレンブタジエンゴム、カルボキシメチルセルロース、ポリフッ化ビニリデン、ポリイミド樹脂、アクリル樹脂、ブチラール樹脂及びそれらの変性物からなる群から選択された少なくとも1種を含む、請求項16~19のいずれか1項に記載のリチウムイオン二次電池用電極材。
- リチウムイオン二次電池用の正極材料である、請求項16~20のいずれか1項に記載のリチウムイオン二次電池用電極材。
- 請求項16~21のいずれか1項に記載のリチウムイオン二次電池用電極材により構成されている電極を備える、リチウムイオン二次電池。
Priority Applications (5)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US15/556,993 US10644318B2 (en) | 2015-05-14 | 2016-05-10 | Carbon material, carbon material-active material composite, electrode material for lithium-ion secondary battery, and lithium-ion secondary battery |
JP2016530266A JP6200593B2 (ja) | 2015-05-14 | 2016-05-10 | 炭素質材料、炭素質材料−活物質複合体、リチウムイオン二次電池用電極材及びリチウムイオン二次電池 |
CN201680007749.6A CN107210443B (zh) | 2015-05-14 | 2016-05-10 | 碳材料、碳材料-活性物质复合体、锂离子二次电池用电极材料及锂离子二次电池 |
KR1020177018093A KR20180006360A (ko) | 2015-05-14 | 2016-05-10 | 탄소질 재료, 탄소질 재료-활물질 복합체, 리튬 이온 이차 전지용 전극재 및 리튬 이온 이차 전지 |
EP16792677.3A EP3297075A4 (en) | 2015-05-14 | 2016-05-10 | Carbon material, carbon material-active material composite, electrode material for lithium-ion secondary battery, and lithium-ion secondary battery |
Applications Claiming Priority (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2015099003 | 2015-05-14 | ||
JP2015-099003 | 2015-05-14 | ||
JP2015-227494 | 2015-11-20 | ||
JP2015227494 | 2015-11-20 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2016181952A1 true WO2016181952A1 (ja) | 2016-11-17 |
Family
ID=57248040
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/JP2016/063824 WO2016181952A1 (ja) | 2015-05-14 | 2016-05-10 | 炭素質材料、炭素質材料-活物質複合体、リチウムイオン二次電池用電極材及びリチウムイオン二次電池 |
Country Status (7)
Country | Link |
---|---|
US (1) | US10644318B2 (ja) |
EP (1) | EP3297075A4 (ja) |
JP (2) | JP6200593B2 (ja) |
KR (1) | KR20180006360A (ja) |
CN (1) | CN107210443B (ja) |
TW (1) | TWI738651B (ja) |
WO (1) | WO2016181952A1 (ja) |
Cited By (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2018163756A (ja) * | 2017-03-24 | 2018-10-18 | 積水化学工業株式会社 | 活物質−炭素材料複合体、非水電解質二次電池用負極、非水電解質二次電池及び炭素材料 |
JP2018163755A (ja) * | 2017-03-24 | 2018-10-18 | 積水化学工業株式会社 | 活物質−炭素材料複合体、非水電解質二次電池用負極、非水電解質二次電池及び炭素材料 |
WO2019026940A1 (ja) * | 2017-08-04 | 2019-02-07 | 積水化学工業株式会社 | 炭素材料、全固体電池用正極、全固体電池用負極、及び全固体電池 |
JP2019050098A (ja) * | 2017-09-08 | 2019-03-28 | 三洋電機株式会社 | 非水電解質二次電池用正極、及び非水電解質二次電池 |
CN110621618A (zh) * | 2017-06-05 | 2019-12-27 | 积水化学工业株式会社 | 含有碳材料的分散液、电极形成用浆料以及非水电解质二次电池用电极的制造方法 |
WO2020017614A1 (ja) * | 2018-07-20 | 2020-01-23 | 株式会社ダイセル | 電池の電極活物質層形成用スラリー |
JP2020528643A (ja) * | 2017-09-19 | 2020-09-24 | エルジー・ケム・リミテッド | リチウム二次電池用正極材、この製造方法、これを含むリチウム二次電池用正極、及びリチウム二次電池 |
KR20210033033A (ko) * | 2018-08-31 | 2021-03-25 | 컨템포러리 엠퍼렉스 테크놀로지 씨오., 리미티드 | 리튬 이온 이차 전지 |
JP2021093292A (ja) * | 2019-12-10 | 2021-06-17 | 株式会社豊田中央研究所 | 電極、電極の製造方法、蓄電デバイス及び蓄電デバイスの製造方法 |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US10873075B2 (en) * | 2017-09-01 | 2020-12-22 | Nanograf Corporation | Composite anode material including particles having buffered silicon-containing core and graphene-containing shell |
KR20200119231A (ko) | 2018-02-09 | 2020-10-19 | 세키스이가가쿠 고교가부시키가이샤 | 탄소 재료, 축전 디바이스용 전극, 축전 디바이스 및 비수 전해질 이차 전지 |
JP6641538B1 (ja) * | 2018-06-25 | 2020-02-05 | 積水化学工業株式会社 | 炭素材料、導電助剤、蓄電デバイス用電極、及び蓄電デバイス |
WO2021025745A2 (en) * | 2019-05-03 | 2021-02-11 | Tda Research, Inc. | Conductive matrix and sulfur composite |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2006228468A (ja) * | 2005-02-15 | 2006-08-31 | Sii Micro Parts Ltd | 電解質二次電池 |
WO2008029502A1 (en) * | 2006-08-29 | 2008-03-13 | Unitika Ltd. | Binder for electrode formation, slurry for electrode formation using the binder, electrode using the slurry, secondary battery using the electrode, and capacitor using the electrode |
WO2014034156A1 (ja) * | 2012-08-27 | 2014-03-06 | 積水化学工業株式会社 | 薄片化黒鉛・樹脂複合材料及びその製造方法 |
JP5636135B1 (ja) * | 2013-03-04 | 2014-12-03 | 積水化学工業株式会社 | 微粒子−薄片化黒鉛複合体、リチウムイオン二次電池用負極材及びそれらの製造方法並びにリチウムイオン二次電池 |
Family Cites Families (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB2296125B (en) | 1994-12-16 | 1998-04-29 | Moli Energy | Pre-graphitic carbonaceous insertion compounds and use as anodes in rechargeable batteries |
JP5114857B2 (ja) | 2006-03-24 | 2013-01-09 | 大日本印刷株式会社 | 非水電解液二次電池用電極板及びその製造方法並びに非水電解液二次電池 |
KR101114122B1 (ko) * | 2006-06-27 | 2012-03-13 | 닛산 지도우샤 가부시키가이샤 | 리튬이온 전지용 복합 양극재료 및 이것을 이용한 전지 |
CN101315343B (zh) * | 2007-05-29 | 2012-12-12 | 上海比亚迪有限公司 | 一种用于测定粉体的体积电阻率的装置和方法 |
WO2009081704A1 (ja) | 2007-12-25 | 2009-07-02 | Kao Corporation | リチウム電池正極用複合材料 |
JP5377946B2 (ja) * | 2007-12-25 | 2013-12-25 | 花王株式会社 | リチウム電池正極用複合材料 |
US9263741B2 (en) * | 2008-12-19 | 2016-02-16 | Nec Energy Devices, Ltd. | Negative electrode for nanaqueous electrolyte secondary battery, nonaqueous electrolyte secondary battery using the same, and method for manufacturing negative electrode for nonaqueous electrolyte secondary battery |
JP5663855B2 (ja) * | 2009-09-30 | 2015-02-04 | 東レ株式会社 | 導電性複合体およびリチウムイオン電池用負極。 |
JP5672859B2 (ja) * | 2010-08-26 | 2015-02-18 | 宇部興産株式会社 | 微細な炭素繊維と複合化されたリチウムチタン複合酸化物電極材料 |
JP5917361B2 (ja) * | 2011-12-16 | 2016-05-11 | Jfeケミカル株式会社 | 非晶質炭素粒子の製造方法、非晶質炭素粒子、リチウムイオン二次電池用負極材料およびリチウムイオン二次電池 |
CN102544461A (zh) | 2012-02-17 | 2012-07-04 | 电子科技大学 | 一种锂离子电池负极材料及其制备方法 |
US10374223B2 (en) | 2013-01-23 | 2019-08-06 | Toray Industries, Inc. | Positive electrode active material/graphene composite particles, positive electrode material for lithium ion cell, and method for manufacturing positive electrode active material/graphene composite particles |
JP6285643B2 (ja) | 2013-03-04 | 2018-02-28 | 積水化学工業株式会社 | リチウムイオン二次電池用負極材及びその製造方法、並びにリチウムイオン二次電池 |
WO2016088682A1 (ja) | 2014-12-02 | 2016-06-09 | 積水化学工業株式会社 | 熱伝導シート及びその製造方法 |
-
2016
- 2016-05-10 KR KR1020177018093A patent/KR20180006360A/ko unknown
- 2016-05-10 US US15/556,993 patent/US10644318B2/en active Active
- 2016-05-10 JP JP2016530266A patent/JP6200593B2/ja active Active
- 2016-05-10 EP EP16792677.3A patent/EP3297075A4/en not_active Withdrawn
- 2016-05-10 CN CN201680007749.6A patent/CN107210443B/zh active Active
- 2016-05-10 WO PCT/JP2016/063824 patent/WO2016181952A1/ja active Application Filing
- 2016-05-13 TW TW105114983A patent/TWI738651B/zh active
-
2017
- 2017-08-14 JP JP2017156502A patent/JP2017216254A/ja active Pending
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2006228468A (ja) * | 2005-02-15 | 2006-08-31 | Sii Micro Parts Ltd | 電解質二次電池 |
WO2008029502A1 (en) * | 2006-08-29 | 2008-03-13 | Unitika Ltd. | Binder for electrode formation, slurry for electrode formation using the binder, electrode using the slurry, secondary battery using the electrode, and capacitor using the electrode |
WO2014034156A1 (ja) * | 2012-08-27 | 2014-03-06 | 積水化学工業株式会社 | 薄片化黒鉛・樹脂複合材料及びその製造方法 |
JP5636135B1 (ja) * | 2013-03-04 | 2014-12-03 | 積水化学工業株式会社 | 微粒子−薄片化黒鉛複合体、リチウムイオン二次電池用負極材及びそれらの製造方法並びにリチウムイオン二次電池 |
Non-Patent Citations (1)
Title |
---|
See also references of EP3297075A4 * |
Cited By (17)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2018163756A (ja) * | 2017-03-24 | 2018-10-18 | 積水化学工業株式会社 | 活物質−炭素材料複合体、非水電解質二次電池用負極、非水電解質二次電池及び炭素材料 |
JP2018163755A (ja) * | 2017-03-24 | 2018-10-18 | 積水化学工業株式会社 | 活物質−炭素材料複合体、非水電解質二次電池用負極、非水電解質二次電池及び炭素材料 |
EP3636593A4 (en) * | 2017-06-05 | 2021-03-03 | Sekisui Chemical Co., Ltd. | DISPERSION LIQUID CONTAINING A CARBONATED MATERIAL, SLURRY FOR ELECTRODE FORMATION, AND PROCESS FOR THE PRODUCTION OF ELECTRODE FOR NON-AQUEOUS ELECTROLYTE SECONDARY BATTERIES |
CN110621618A (zh) * | 2017-06-05 | 2019-12-27 | 积水化学工业株式会社 | 含有碳材料的分散液、电极形成用浆料以及非水电解质二次电池用电极的制造方法 |
JPWO2019026940A1 (ja) * | 2017-08-04 | 2020-06-25 | 積水化学工業株式会社 | 炭素材料、全固体電池用正極、全固体電池用負極、及び全固体電池 |
WO2019026940A1 (ja) * | 2017-08-04 | 2019-02-07 | 積水化学工業株式会社 | 炭素材料、全固体電池用正極、全固体電池用負極、及び全固体電池 |
JP7011427B2 (ja) | 2017-09-08 | 2022-02-10 | 三洋電機株式会社 | 非水電解質二次電池用正極、及び非水電解質二次電池 |
JP2019050098A (ja) * | 2017-09-08 | 2019-03-28 | 三洋電機株式会社 | 非水電解質二次電池用正極、及び非水電解質二次電池 |
JP2020528643A (ja) * | 2017-09-19 | 2020-09-24 | エルジー・ケム・リミテッド | リチウム二次電池用正極材、この製造方法、これを含むリチウム二次電池用正極、及びリチウム二次電池 |
US11637275B2 (en) | 2017-09-19 | 2023-04-25 | Lg Energy Solution, Ltd. | Positive electrode material for lithium secondary battery, method of preparing the same, and positive electrode for lithium secondary battery and lithium secondary battery which include the positive electrode material |
WO2020017614A1 (ja) * | 2018-07-20 | 2020-01-23 | 株式会社ダイセル | 電池の電極活物質層形成用スラリー |
KR20210033033A (ko) * | 2018-08-31 | 2021-03-25 | 컨템포러리 엠퍼렉스 테크놀로지 씨오., 리미티드 | 리튬 이온 이차 전지 |
JP2021534555A (ja) * | 2018-08-31 | 2021-12-09 | 寧徳時代新能源科技股▲分▼有限公司Contemporary Amperex Technology Co., Limited | リチウムイオン二次電池 |
JP7106746B2 (ja) | 2018-08-31 | 2022-07-26 | 寧徳時代新能源科技股▲分▼有限公司 | リチウムイオン二次電池 |
KR102535068B1 (ko) * | 2018-08-31 | 2023-05-26 | 컨템포러리 엠퍼렉스 테크놀로지 씨오., 리미티드 | 리튬 이온 이차 전지 |
JP2021093292A (ja) * | 2019-12-10 | 2021-06-17 | 株式会社豊田中央研究所 | 電極、電極の製造方法、蓄電デバイス及び蓄電デバイスの製造方法 |
JP7176504B2 (ja) | 2019-12-10 | 2022-11-22 | 株式会社豊田中央研究所 | 電極、電極の製造方法、蓄電デバイス及び蓄電デバイスの製造方法 |
Also Published As
Publication number | Publication date |
---|---|
EP3297075A1 (en) | 2018-03-21 |
JP6200593B2 (ja) | 2017-09-20 |
US20180062179A1 (en) | 2018-03-01 |
EP3297075A4 (en) | 2018-12-19 |
TWI738651B (zh) | 2021-09-11 |
KR20180006360A (ko) | 2018-01-17 |
JPWO2016181952A1 (ja) | 2017-06-01 |
CN107210443B (zh) | 2021-06-18 |
JP2017216254A (ja) | 2017-12-07 |
US10644318B2 (en) | 2020-05-05 |
TW201703321A (zh) | 2017-01-16 |
CN107210443A (zh) | 2017-09-26 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
JP6200593B2 (ja) | 炭素質材料、炭素質材料−活物質複合体、リチウムイオン二次電池用電極材及びリチウムイオン二次電池 | |
JP5969126B2 (ja) | キャパシタ用電極材及びその製造方法、並びに電気二重層キャパシタ | |
US10680237B2 (en) | Active material-exfoliated graphite composite, negative electrode material for lithium ion secondary battery, and lithium ion secondary battery | |
TW201815667A (zh) | 蓄電裝置用電極材料、蓄電裝置用電極及蓄電裝置 | |
WO2017090553A1 (ja) | キャパシタ用電極材及びキャパシタ | |
JP2020155223A (ja) | リチウムイオン二次電池用正極材料、リチウムイオン二次電池、リチウムイオン二次電池用正極の製造方法、及びリチウムイオン二次電池の製造方法 | |
WO2020091876A1 (en) | Advanced negative electrode architecture for high power applications | |
JP7144013B2 (ja) | 硫黄-炭素材料複合体、リチウム硫黄二次電池用正極材及びリチウム硫黄二次電池 | |
TW201817675A (zh) | 碳材料、電容器用電極片材及電容器 | |
JP5334506B2 (ja) | 非水電解質二次電池の正極用組成物の製造方法 | |
WO2020189662A1 (ja) | 複合材料、蓄電デバイス用電極材料、及び蓄電デバイス | |
JP2017182913A (ja) | 複合体及びその製造方法、リチウムイオン二次電池用正極材、並びにリチウムイオン二次電池 | |
JP6856448B2 (ja) | 電極材及び蓄電デバイス | |
TW201902823A (zh) | 含有碳材料之分散液、電極形成用漿料、及非水電解質二次電池用電極之製造方法 | |
JP2018159059A (ja) | 炭素材料・樹脂複合材料 | |
JP6837780B2 (ja) | 活物質−炭素材料複合体、非水電解質二次電池用正極、非水電解質二次電池及び炭素材料 | |
KR100663182B1 (ko) | 고에너지밀도 리튬 이차전지용 음극 활물질 | |
JP2021051882A (ja) | 炭素材料複合体、蓄電デバイス用電極材料、及び蓄電デバイス | |
JP2018163756A (ja) | 活物質−炭素材料複合体、非水電解質二次電池用負極、非水電解質二次電池及び炭素材料 |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
ENP | Entry into the national phase |
Ref document number: 2016530266 Country of ref document: JP Kind code of ref document: A |
|
121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 16792677 Country of ref document: EP Kind code of ref document: A1 |
|
ENP | Entry into the national phase |
Ref document number: 20177018093 Country of ref document: KR Kind code of ref document: A |
|
WWE | Wipo information: entry into national phase |
Ref document number: 15556993 Country of ref document: US |
|
NENP | Non-entry into the national phase |
Ref country code: DE |