WO2013128936A1 - Composé de matériau actif, son procédé de production, matériau actif d'électrode positive pour batteries secondaires à électrolyte non aqueux, et batterie secondaire à électrolyte non aqueux - Google Patents

Composé de matériau actif, son procédé de production, matériau actif d'électrode positive pour batteries secondaires à électrolyte non aqueux, et batterie secondaire à électrolyte non aqueux Download PDF

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WO2013128936A1
WO2013128936A1 PCT/JP2013/001242 JP2013001242W WO2013128936A1 WO 2013128936 A1 WO2013128936 A1 WO 2013128936A1 JP 2013001242 W JP2013001242 W JP 2013001242W WO 2013128936 A1 WO2013128936 A1 WO 2013128936A1
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active material
particles
lithium
electrolyte secondary
sample
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PCT/JP2013/001242
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English (en)
Japanese (ja)
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晶 小島
敏勝 小島
田渕　光春
境　哲男
一仁 川澄
淳一 丹羽
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株式会社豊田自動織機
独立行政法人産業技術総合研究所
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Publication of WO2013128936A1 publication Critical patent/WO2013128936A1/fr

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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/58—Selection of substances as active materials, active masses, active liquids of inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy; of polyanionic structures, e.g. phosphates, silicates or borates
    • H01M4/5825—Oxygenated metallic salts or polyanionic structures, e.g. borates, phosphates, silicates, olivines
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
    • B60L50/00—Electric propulsion with power supplied within the vehicle
    • B60L50/50—Electric propulsion with power supplied within the vehicle using propulsion power supplied by batteries or fuel cells
    • B60L50/52—Electric propulsion with power supplied within the vehicle using propulsion power supplied by batteries or fuel cells characterised by DC-motors
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
    • B60L50/00—Electric propulsion with power supplied within the vehicle
    • B60L50/50—Electric propulsion with power supplied within the vehicle using propulsion power supplied by batteries or fuel cells
    • B60L50/60—Electric propulsion with power supplied within the vehicle using propulsion power supplied by batteries or fuel cells using power supplied by batteries
    • B60L50/64—Constructional details of batteries specially adapted for electric vehicles
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
    • B60L53/00—Methods of charging batteries, specially adapted for electric vehicles; Charging stations or on-board charging equipment therefor; Exchange of energy storage elements in electric vehicles
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
    • B60L58/00—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles
    • B60L58/10—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles for monitoring or controlling batteries
    • B60L58/24—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles for monitoring or controlling batteries for controlling the temperature of batteries
    • B60L58/27—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles for monitoring or controlling batteries for controlling the temperature of batteries by heating
    • 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
    • H01M4/136—Electrodes based on inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy
    • 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
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
    • B60L2240/00—Control parameters of input or output; Target parameters
    • B60L2240/40—Drive Train control parameters
    • B60L2240/54—Drive Train control parameters related to batteries
    • B60L2240/545—Temperature
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
    • B60L2270/00—Problem solutions or means not otherwise provided for
    • B60L2270/10—Emission reduction
    • B60L2270/14—Emission reduction of noise
    • B60L2270/145—Structure borne vibrations
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10—Energy storage using batteries
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00—Road transport of goods or passengers
    • Y02T10/60—Other road transportation technologies with climate change mitigation effect
    • Y02T10/70—Energy storage systems for electromobility, e.g. batteries
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00—Road transport of goods or passengers
    • Y02T10/60—Other road transportation technologies with climate change mitigation effect
    • Y02T10/7072—Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T90/00—Enabling technologies or technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02T90/10—Technologies relating to charging of electric vehicles
    • Y02T90/14—Plug-in electric vehicles

Definitions

  • the present invention relates to an active material composite used for an active material for a nonaqueous electrolyte secondary battery and a method for producing the same, a positive electrode active material for a nonaqueous electrolyte secondary battery, and a nonaqueous electrolyte secondary battery.
  • lithium ion secondary batteries are small and have high energy density, and are widely used as power sources for portable electronic devices.
  • a lithium ion secondary battery is used as a vehicle drive source.
  • lithium silicate compounds, lithium borate compounds, and lithium phosphate compounds are known as positive electrode active materials for lithium ion secondary batteries.
  • lithium silicate compounds are inexpensive and have a low environmental impact because they are composed of abundant constituent metal elements.
  • the material has a high theoretical charge / discharge capacity and does not release oxygen at a high temperature.
  • Li 2 FeSiO 4 theoretical capacity 331.3 mAh / g
  • Li 2 MnSiO 4 theoretical capacity 333.2 mAh
  • Lithium silicate compounds such as / g
  • lithium borate compounds are also inexpensive, have a large amount of resources, have a low environmental burden, have a high theoretical charge / discharge capacity, and do not release oxygen at high temperatures. It is attracting attention as a material.
  • a lithium borate compound for example, LiFeBO 3 (theoretical capacity 220 mAh / g), LiMnBO 3 (theoretical capacity 222 mAh / g), and the like are known.
  • the lithium borate material is a material that can be expected to improve the energy density by using boron (B), which is the lightest element in the polyanion unit, and the true density (3.46 g / cm 3) of the borate material. ) Is smaller than the true density (3.60 g / cm 3 ) of the olivine iron phosphate material, and weight reduction can also be expected.
  • the lithium phosphate compound is represented by LiMPO 4 (M is a metal such as Mn, Fe, Co), and a hetero element PO 4 3- polyanion having a large electronegativity is arranged around the central metal M. For this reason, it is said that the thermal stability is higher than that of layered LiCoO 2 or the like in which oxygen atoms are directly coordinated to the transition metal.
  • each compound is also subjected to a carbon coating treatment.
  • carbon is further added to the lithium silicate compound. It is also disclosed that the coating process is performed.
  • the present invention has been made in view of such circumstances, and an active material composite capable of increasing the charge / discharge capacity of a battery, a method for producing the same, a positive electrode active material for a non-aqueous electrolyte secondary battery, and a non-aqueous electrolyte two. It is an object to provide a secondary battery.
  • active material particles made of an active material and having an average particle size of 100 nm or less are bonded to conductive particles made of a conductive material and having an average particle size of 100 nm or less.
  • the specific surface area is 150 m 2 / g or more.
  • the method for producing an active material composite according to the present invention is a method for producing the active material composite as described above, and includes an energy application step for applying mechanical energy to the active material and the conductive material. It is characterized by that.
  • the positive electrode active material for a non-aqueous electrolyte secondary battery of the present invention is characterized by comprising the active material composite described above or the active material composite manufactured by the manufacturing method described above.
  • the positive electrode for nonaqueous electrolyte secondary batteries of the present invention is characterized by having the positive electrode active material for nonaqueous electrolyte secondary batteries described above.
  • the nonaqueous electrolyte secondary battery of the present invention is characterized by comprising the positive electrode for a nonaqueous electrolyte secondary battery described above, a negative electrode, and an electrolyte.
  • the active material composite of the present invention fine active material particles and fine conductive particles are bonded to each other, so that the charge / discharge capacity of the battery can be increased. Since the positive electrode active material for a nonaqueous electrolyte secondary battery, the positive electrode for a nonaqueous electrolyte secondary battery, and the nonaqueous electrolyte secondary battery of the present invention use the active material composite, the charge / discharge capacity can be increased. it can.
  • FIG. 1 The upper diagram of FIG. 1 is an SEM cross-sectional photograph of sample 1 (one scale of 1 ⁇ m), and the lower diagram of FIG. 1 is an SEM cross-sectional photograph of sample 1 (one scale of 0.2 ⁇ m), surrounded by a dotted line in FIG. It is an enlarged photograph of. 2 is a SEM cross-sectional photograph of sample 1 (one scale 0.1 ⁇ m). It is a figure which shows the element mapping using the energy dispersive X-ray-analysis apparatus (EDX) of the surface vicinity of the secondary particle of the sample 1.
  • EDX energy dispersive X-ray-analysis apparatus
  • FIG. 2 is a SEM photograph (one scale 0.1 ⁇ m) of the surface of secondary particles of sample 1.
  • 2 is a cross-sectional explanatory view of an active material composite of Sample 1.
  • FIG. 2 is a SEM cross-sectional photograph of sample 2 (one scale 0.2 ⁇ m).
  • 3 is a SEM cross-sectional photograph (one scale 0.5 ⁇ m) of Sample 3.
  • 4 is a SEM cross-sectional photograph of sample 3 (one scale 0.1 ⁇ m).
  • FIG. 4 is an SEM photograph (one scale 0.1 ⁇ m) of the particle surface of sample 3.
  • FIG. 4 is an SEM photograph (one scale 0.1 ⁇ m) of the particle surface of sample 5.
  • FIG. 4 is a diagram showing a charge / discharge curve of a battery produced using Sample 1.
  • FIG. 3 is a diagram showing a charge / discharge curve of a battery produced using Sample 2.
  • FIG. 3 is a diagram showing a charge / discharge curve of a battery manufactured using Sample 3.
  • FIG. 6 is a diagram showing a charge / discharge curve of a battery manufactured using Sample 4.
  • FIG. 4 is a diagram showing a cycle test result of a battery manufactured using Sample 1. It is a figure which shows the rate test result of the battery produced using the sample 1.
  • FIG. 4 is a diagram showing a cycle test result of a battery manufactured using Sample 1. It is a figure which shows the rate test result of the battery produced using the sample 1.
  • FIG. 20 is an SEM photograph of Li 2 MnSiO 4 immediately after synthesis, and the upper diagram in FIG. 20 is a high-magnification SEM photograph, and the lower diagram in FIG. 20 is a low-magnification SEM photograph.
  • FIG. 21 is an SEM photograph of Sample 6, the upper drawing of FIG. 21 is a low magnification SEM photograph, and the lower drawing of FIG. 21 is a high magnification SEM photograph. 3 is a SEM photograph of Sample 8.
  • the XRD patterns of Li 2 MnSiO 4 immediately after synthesis and Samples 6 to 8 are shown.
  • the charging / discharging curve of the battery using the sample 6 is shown.
  • the charging / discharging curve of the battery using the sample 7 is shown.
  • the charging / discharging curve of the battery using the sample 8 is shown.
  • An active material composite according to an embodiment of the present invention and a manufacturing method thereof, a positive electrode active material for a nonaqueous electrolyte secondary battery, a nonaqueous electrolyte secondary battery, and a vehicle will be described in detail.
  • the active material composite according to the present invention comprises active material particles made of an active material having an average particle size of 100 nm or less, and conductive particles made of a conductive material having an average particle size of 100 nm or less. It consists of a composite formed by bonding.
  • the charge / discharge capacity of the battery can be increased as shown in Examples described later.
  • the reason is that the active material particles and the conductive particles are joined to each other in a fine particle state at the nano level, thereby increasing the number of conductive paths composed of the conductive particles in the active material complex. This is presumed to be due to the increase in the utilization rate of the active material due to the active movement of electrons. *
  • the specific surface area of the active material composite is 150 m 2 / g or more, preferably 170 m 2 / g or more.
  • the average particle diameter of the active material particles is 100 nm or less
  • the average particle diameter of the conductive particles is 100 nm or less.
  • the average particle diameter of each particle is the maximum diameter of a plurality of particles obtained by analyzing an image of the active material complex using a transmission electron microscope (TEM) or the like (the distance between two parallel lines sandwiching the particles). (Maximum value) is a value calculated by actual measurement. *
  • the average particle diameter of the active material particles exceeds 100 nm, or when the average particle diameter of the conductive particles exceeds 100 nm, the effect of increasing the charge / discharge capacity of the battery may be reduced.
  • the average particle diameter of the active material particles is 10 nm or more and 90 nm or less, and the average particle diameter of the conductive particles is 2 nm or more and 50 nm or less. In this case, the charge / discharge capacity of the battery is further increased. More preferably, the average particle size of the active material particles is 10 nm to 50 nm, and the average particle size of the conductive particles is 2 nm to 10 nm.
  • the active material particles and the conductive particles are mixed and bonded as primary particles to each other in a nano-level fine particle state to form a composite that is a secondary particle.
  • the average particle size of the active material complex is preferably 0.7 ⁇ m or more and 20 ⁇ m or less, and more preferably 1 ⁇ m or more and 10 ⁇ m or less.
  • the average particle diameter of the active material composite is too small, granulation of the active material composite is not yet developed, and the composite of the active material particles and the conductive particles is insufficient.
  • the average particle size of the active material complex is excessive, the rate at which the active material complex occludes / releases lithium ions may decrease.
  • the specific surface area of the active material composite is 150 m 2 / g or more, preferably 170 m 2 / g or more.
  • the specific surface area refers to the BET specific surface area.
  • the upper limit of the specific surface area of the active material composite is preferably 300 m 2 / g, and more preferably 250 m 2 / g.
  • the specific surface area of the active material composite is too small, the charge / discharge capacity of the battery may be reduced.
  • the specific surface area of the active material composite is excessive, the active material composite is too small, and there is a possibility that the composite of the conductive particles and the active material particles is insufficient.
  • the active material particles and the conductive particles may be uniformly finely mixed and bonded to each other.
  • the active material complex is preferably composed of a core part and a surface layer covering the core part.
  • the surface layer may contain more carbon than the core portion.
  • the thickness of the surface layer is preferably 500 nm or more and 2 ⁇ m or less.
  • Fine surface particles are preferably adhered to the surface of the active material composite.
  • the average particle size of the surface particles is preferably 20 nm or more and 100 nm or less, more preferably 30 nm or more and 90 nm or less, and preferably 35 nm or more and 75 nm or less.
  • Examples of surface particles include: A part of the raw material of the active material particles may be included. When the active material composite has the surface particles, the reaction in which the active material particles occlude / release lithium ions is promoted.
  • the active material constituting the active material particles may be made of a material that can occlude and release lithium ions.
  • the active material for nonaqueous electrolyte secondary batteries can be used for the electrode of a lithium ion secondary battery.
  • the active material is preferably composed of one or more members selected from the group consisting of a lithium silicate compound, a lithium phosphate compound, and a lithium borate compound. According to the active material composite including the active material particles made of such an active material, it constitutes an active material for a non-aqueous electrolyte secondary battery, and further an active material for a lithium ion secondary battery or a lithium secondary battery. can do.
  • the lithium silicate-based compound may be, for example, at least one selected from the group consisting of lithium iron silicate (Li 2 FeSiO 4 ) and lithium manganese silicate (Li 2 MnSiO 4 ).
  • the lithium iron silicate is represented by, for example, Li 2 FeSiO 4 .
  • the lithium manganese silicate is represented by, for example, Li 2 MnSiO 4 .
  • the conductive material constituting the conductive particles a material having higher conductivity than the active material is used.
  • a carbon material is preferably used as the conductive material.
  • the carbon material acetylene black (AB), ketjen black (KB), carbon black, carbon nanotube, graphene, carbon fiber, graphite, or the like can be used. Among these, acetylene black (AB), ketjen black (KB), and carbon black are preferable.
  • the mass ratio of the conductive particles when the active material particles are 100 parts by mass is preferably 2 parts by mass or more and 60 parts by mass or less, and more preferably 5 parts by mass or more and 30 parts by mass. It may be the following. In this case, the active material particles and the conductive particles are uniformly dispersed, and the electric capacity can be greatly extracted.
  • the active material used in the energy application step may be, for example, any one of a lithium silicate compound, a lithium phosphate compound, and a lithium borate compound.
  • the lithium silicate compound is, for example, a lithium silicate compound having a composition formula of Li 2 M 1 SiO 4 (M 1 is Fe, Mn, Co), or a composition formula of Li 2 + ab Ab M 1-x M ' x SiO 4 + ⁇ (wherein A is at least one element selected from the group consisting of Na, K, Rb and Cs, and M is at least one element selected from the group consisting of Fe, Mn and Co) , M ′ is at least one element selected from the group consisting of Mg, Ca, Al, Ni, Nb, Ti, Cr, Cu, Zn, Zr, V, Mo, and W.
  • the subscripts are as follows.
  • it is made of a compound represented by 0 ⁇ a ⁇ 1, 0 ⁇ b ⁇ 0.2, 0 ⁇ x ⁇ 0.5, ⁇ ⁇ 0).
  • Li 2 FeSiO 4, Li 2 MnSiO 4, Li 2 CoSiO 4 can be cited.
  • the lithium silicate compound can be produced, for example, by a molten salt method, a solid phase method, a hydrothermal method, or the like. Especially, it is good to manufacture by the molten salt method.
  • the molten salt method is a method of synthesizing a lithium silicate compound in a molten salt containing an alkali metal salt.
  • the alkali metal salt used in the molten salt method include at least one selected from the group consisting of a lithium salt, a potassium salt, a sodium salt, a rubium salt, and a cesium salt. Of these, lithium salts are desirable.
  • a molten salt containing a lithium salt is used, the formation of an impurity phase is small, and a lithium silicate compound containing excessive lithium atoms is likely to be formed.
  • the lithium silicate compound thus obtained is a positive electrode material for lithium ion batteries having good cycle characteristics and high capacity. *
  • the alkali metal salt used in the molten salt method contains at least one of alkali metal chloride, alkali metal carbonate, alkali metal nitrate, and alkali metal hydroxide.
  • the alkali metal carbonate is preferably an alkali metal carbonate, and further preferably contains lithium carbonate.
  • a carbonate mixture comprising at least one alkali metal carbonate selected from the group consisting of potassium carbonate, sodium carbonate, rubidium carbonate and cesium carbonate and lithium carbonate is preferable.
  • the reaction by performing the reaction at a relatively low temperature of 400 to 650 ° C. in the molten salt of the mixture, the growth of crystal grains is suppressed, and the average particle diameter becomes fine particles of 50 nm to 10 ⁇ m. The amount is greatly reduced. As a result, when used as a positive electrode active material for a non-aqueous electrolyte secondary battery, the material has good cycle characteristics and high capacity.
  • a molten salt of a carbonate mixture consisting of at least one alkali metal carbonate and lithium carbonate selected from the group consisting of potassium carbonate, sodium carbonate, rubidium carbonate and cesium carbonate it is represented by Li 2 SiO 3.
  • the lithium silicate compound may be reacted with a substance containing at least one metal element selected from the group consisting of iron and manganese at 400 to 650 ° C.
  • the specific reaction method is not particularly limited.
  • the above-described carbonate mixture, lithium silicate compound, and a substance containing a metal element are mixed to form a ball mill. Or the like, and then the carbonate mixture may be melted by heating. Thereby, in molten carbonate, reaction with a lithium silicate compound and the said metal element advances, and a lithium silicate type compound can be obtained.
  • the mixing ratio of the raw material composed of the lithium silicate compound and the metal element-containing material and the carbonate mixture is not particularly limited, and the amount of the raw material can be uniformly dispersed in the molten salt of the carbonate mixture.
  • the total amount of the molten salt raw material is preferably in the range of 20 to 300 parts by mass with respect to 100 parts by mass of the total amount of the carbonate mixture.
  • the amount is more preferably in the range of ⁇ 80 parts by mass.
  • the above-described reaction is performed in a mixed gas atmosphere containing carbon dioxide and a reducing gas because the metal element stably exists as a divalent ion during the reaction. Under this atmosphere, the metal element can be stably maintained in a divalent state.
  • the reducing gas may be 0.01 to 0.5 mol, preferably 0.03 to 0.4 mol, per 1 mol of carbon dioxide.
  • the reducing gas for example, hydrogen, carbon monoxide and the like can be used, and hydrogen is particularly preferable.
  • the pressure of the mixed gas of carbon dioxide and reducing gas there is no particular limitation on the pressure of the mixed gas of carbon dioxide and reducing gas, and it may be usually atmospheric pressure, but it may be under pressure or under reduced pressure.
  • the reaction time between the lithium silicate compound and the substance containing the metal element is usually 0.1 to 30 hours, preferably 5 to 25 hours.
  • the target lithium silicate compound can be obtained by removing the alkali metal carbonate used as the flux.
  • the alkali metal carbonate may be dissolved and removed by washing the product using a solvent capable of dissolving the alkali metal carbonate.
  • a solvent capable of dissolving the alkali metal carbonate for example, although water can be used as the solvent, it is preferable to use a nonaqueous solvent such as alcohol or acetone in order to prevent oxidation of the transition metal contained in the lithium silicate compound.
  • acetic anhydride and acetic acid in a mass ratio of 2: 1 to 1: 1.
  • this mixed solvent when acetic acid reacts with the alkali metal carbonate to produce water, acetic anhydride takes in the water and produces acetic acid. Therefore, it is possible to suppress the separation of water.
  • acetic anhydride and acetic acid are used, first, acetic anhydride is mixed with the product, ground with a mortar or the like to make particles fine, and then acetic anhydride is added in a state where acetic anhydride is intimately mixed with the particles. It is preferable. According to this method, since the water produced by the reaction of acetic acid and alkali metal carbonate reacts quickly with acetic anhydride, the chance of the product and water coming into contact with each other can be reduced. Can be suppressed. *
  • lithium borate compound examples include LiM 2 BO 3 (M 2 is composed of at least one selected from the group consisting of Mn, Fe, and Co).
  • M 2 is composed of at least one selected from the group consisting of Mn, Fe, and Co.
  • M 2 is at least one element selected from the group consisting of Fe, Mn, and Co
  • M ′ is a group consisting of Mg, Ca, Al, Ni, Nb, Mo, W, Ti, and Zr.
  • This compound is, for example, in a reducing atmosphere in a molten salt of a carbonate mixture comprising at least one alkali metal carbonate and lithium carbonate selected from the group consisting of potassium carbonate, sodium carbonate, rubidium carbonate and cesium carbonate.
  • a divalent metal compound containing at least one compound selected from the group consisting of a divalent iron compound and a divalent manganese compound, boric acid, and lithium hydroxide at 400 to 650 ° C. can do.
  • a lithium borate compound containing iron or manganese can be obtained under relatively mild conditions.
  • the obtained lithium borate compound is a borate compound that is fine, has a small impurity phase, contains excessive lithium atoms, and has good cycle characteristics when used as a positive electrode active material of a lithium ion secondary battery. It becomes a material having a capacity.
  • the conductive material used in the energy application step is made of, for example, a carbon material.
  • a carbon material acetylene black (AB), ketjen black (KB), carbon black, carbon nanotube, graphene, carbon fiber, graphite and the like can be used.
  • acetylene black (AB) is preferred because of its high specific surface area.
  • Ketjen black (KB) and carbon black are preferred. *
  • the average particle diameter of the active material used in the energy application step is preferably 200 nm to 5 ⁇ m, and the average particle diameter of the conductive material is preferably 100 nm to 5 ⁇ m.
  • active material particles having an average particle size of 100 nm or less and conductive particles having an average particle size of 100 nm or less by applying mechanical energy to the active material and the conductive material in the energy application step. Can be easily obtained.
  • the energy application step may be a step of applying mechanical energy by milling.
  • mechanical energy can be uniformly given to the active material and the conductive material.
  • the milling method ball milling in which mechanical energy is introduced by moving the container by an external force in a state where a hard ball is accommodated in the container together with the sample is preferable.
  • the ball milling device any of a planetary type that gives energy to the sample by rotation and revolution and a vibration type that gives energy to the sample by vibration in the horizontal direction or the vertical direction can be adopted. *
  • the active material and the conductive material may be rotated by a ball mill at a relatively high speed.
  • a mechanical milling device Fritch Japan Co., Ltd., planetary ball mill P-7 series
  • the rotational speed of the ball mill is preferably greater than 700 rpm and less than 1100 rpm.
  • both the active material particles and the conductive particles can be uniformly dispersed and mixed with an average particle size of 100 nm or less to be amorphized and combined.
  • the average particle diameter of the active material particles and the conductive particles may be larger than 100 nm. If it exceeds 1100 rpm, there is a risk of increased contamination of impurities.
  • the rotation speed of a ball mill is 750 rpm or more and less than 1000 rpm.
  • the active material particles and the conductive particles can be more uniformly dispersed and mixed.
  • a diffraction peak derived from the (111) plane (2 ⁇ ) for a sample containing a lithium silicate compound precursor having crystallinity before milling is B (111) crystal, and when the half width of the same peak of the sample after milling is B (111) mill, B (111) crystal / B (111) mill.
  • the ratio is preferably in the range of 0.7 to 1.1, more preferably 0.8 to 1.0.
  • the active material is a lithium silicate compound
  • Li 2 CO 3 is added to the lithium silicate compound, and the lithium silicate compound is made amorphous by ball milling. Mix evenly until By the presence of Li 2 CO 3 , lithium deficiency of the lithium silicate compound is suppressed, and a high charge / discharge capacity is exhibited.
  • the active material and the conductive material can be mixed in an inert gas atmosphere (argon gas, nitrogen gas) or in an air atmosphere.
  • the mixing ratio of the lithium silicate compound and the conductive material may be 5 to 50 parts by mass of the carbon material with respect to 100 parts by mass of the lithium silicate compound. . *
  • a heat treatment step may be performed in which heat treatment is performed on the mixture of the active material and the conductive material to which mechanical energy is applied.
  • the mixed active material and conductive material are heated at a predetermined temperature.
  • the heat treatment temperature is preferably 500 to 800 ° C. If the heat treatment temperature is too low, it is difficult to deposit carbon uniformly around the lithium silicate compound, while if the heat treatment temperature is too high, decomposition of the lithium silicate compound and lithium deficiency may occur. This is not preferable because the charge / discharge capacity decreases.
  • the heat treatment time is usually 1 to 10 hours. *
  • the heat treatment is preferably performed in a reducing atmosphere in order to keep the transition metal ions contained in the lithium silicate compound divalent.
  • a reducing atmosphere in this case, in order to suppress the reduction of the divalent transition metal ion to the metal state, as in the synthesis reaction of the lithium silicate compound in the molten salt, the reducing atmosphere is reduced with carbon dioxide.
  • a gas mixed gas atmosphere is preferred. The mixing ratio of carbon dioxide and reducing gas may be the same as in the synthesis reaction of the lithium silicate compound. *
  • the heat treatment is preferably performed in a mixed atmosphere of carbon dioxide and a reducing gas. The reason is that decomposition of the lithium borate compound is suppressed.
  • the heat treatment is preferably performed in a mixed atmosphere of carbon dioxide and a reducing gas or in an inert gas atmosphere. The reason is that decomposition of the lithium phosphate compound can be suppressed.
  • Positive electrode active material for nonaqueous electrolyte secondary battery is composed of the above active material composite. According to such a non-aqueous electrolyte secondary battery positive electrode active material, a battery having excellent charge / discharge characteristics can be configured.
  • the positive electrode for nonaqueous electrolyte secondary battery is composed of the positive electrode active material for nonaqueous electrolyte secondary battery and a current collector.
  • the positive electrode for a nonaqueous electrolyte secondary battery has a positive electrode active material made of the above active material composite, and can have the same structure as a normal positive electrode for a nonaqueous electrolyte secondary battery.
  • the active material composite may include acetylene black (AB), ketjen black (KB), a conductive additive such as vapor grown carbon fiber (Vapor Grown Carbon Fiber: VGCF), polyvinylidene fluoride (Polyvinylidene Fluoride: PVdF),
  • a binder such as polytetrafluoroethylene (PTFE) and styrene-butadiene rubber (SBR) and a solvent such as N-methyl-2-pyrrolidone (NMP)
  • the amount of the conductive aid used is not particularly limited, but can be 5 to 20 parts by mass with respect to 100 parts by mass of the active material composite, for example.
  • the amount of the binder used is not particularly limited, but may be 5 to 20 parts by mass with respect to 100 parts by mass of the active material composite, for example.
  • a mixture of the active material composite, the conductive aid and the binder described above is kneaded using a mortar or a press to form a film, and this is crimped to the current collector with a press.
  • the positive electrode can be manufactured also by the method to do. *
  • the current collector is not particularly limited, and materials conventionally used as positive electrodes for nonaqueous electrolyte secondary batteries, such as aluminum foil, aluminum mesh, and stainless steel mesh, can be used. Furthermore, a carbon nonwoven fabric, a carbon woven fabric, etc. can be used as a collector. *
  • the shape and thickness of the positive electrode for a nonaqueous electrolyte secondary battery is not particularly limited.
  • the positive electrode for a nonaqueous electrolyte secondary battery is filled with an active material and then compressed to have a thickness of 10 to 200 ⁇ m, more preferably 20 ⁇ m. It is preferable that the thickness is 100 ⁇ m. Therefore, the filling amount of the active material may be appropriately determined so as to have the above-described thickness after compression according to the type and structure of the current collector to be used. *
  • Nonaqueous electrolyte secondary battery includes the above-described positive electrode for a nonaqueous electrolyte secondary battery.
  • the nonaqueous electrolyte secondary battery can be manufactured by a known method.
  • the positive electrode described above is used as the positive electrode material.
  • the negative electrode material is composed of an element compound that can occlude and release lithium ions and can be alloyed with lithium or / and an element compound that can be alloyed with lithium.
  • Elements capable of alloying with lithium are Na, K, Rb, Cs, Fr, Be, Mg, Ca, Sr, Ba, Ra, Ti, Ag, Zn, Cd, Al, Ga, In, Si, Ge.
  • the negative electrode material examples include known metal-based materials such as lithium metal and graphite, silicon-based materials such as SiOx (0.5 ⁇ x ⁇ 1.5), alloy-based materials such as copper-tin and cobalt-tin, An oxide material such as lithium titanate is preferably used. *
  • a lithium salt such as lithium perchlorate, LiPF 6 , LiBF 4 , LiCF 3 SO 3 or the like is added to a known non-aqueous solvent such as ethylene carbonate, dimethyl carbonate, propylene carbonate, dimethyl carbonate to 0.5 mol / L to 1
  • a solution dissolved at a concentration of 7 mol / L may be used, and other known battery components may be used.
  • lithium secondary battery When metal lithium is used as the negative electrode, a lithium secondary battery is obtained, and when a material other than metal lithium is used as the negative electrode, a lithium ion secondary battery is obtained.
  • many secondary batteries that perform a battery reaction with these lithium ions are non-aqueous electrolyte secondary batteries.
  • the non-aqueous electrolyte secondary battery can be mounted on a vehicle.
  • the vehicle may be an electric vehicle or a hybrid vehicle.
  • the nonaqueous electrolyte secondary battery is preferably connected to, for example, a traveling motor mounted on a vehicle and used as a drive source. In this case, a high driving torque can be output for a long time.
  • the non-aqueous electrolyte secondary battery can be mounted on devices other than vehicles such as personal computers and portable communication devices. *
  • the active material complexes of Samples 1 to 5 were manufactured by the following method.
  • the active material composites of Samples 1 to 5 are composed of Li 2 FeSiO 4 and carbon.
  • the mixing ratio is 100 parts by mass of the total amount of iron and lithium silicate. It was set as the mass part. Acetone (20 ml) was added thereto, mixed in a zirconia ball mill at 500 rpm for 60 minutes, and dried.
  • the obtained powder was heated in a gold crucible and heated to 500 ° C. in a mixed gas atmosphere of carbon dioxide (flow rate: 100 ml min-1) and hydrogen (flow rate: 3 ml min-1) to form carbonate.
  • the mixture was allowed to react for 13 hours in the molten state. After the reaction, when the temperature was lowered to 400 ° C., the entire reactor core was taken out from the electric furnace, which was a heater, and rapidly cooled to room temperature through the gas.
  • the obtained active material particles and acetylene black (AB, average particle size 0.3 ⁇ m) were mixed at a mass ratio of 5: 4, and a mechanical milling device (French Japan Co., Ltd., planetary ball mill P-7) was used. Then, mechanical milling treatment was performed under the following predetermined conditions in an air atmosphere to give mechanical energy to the mixture. This step was performed by putting 50 g of ⁇ 4 mm zirconia balls and 300 mg of the mixture in a ball mill grinding container made of zirconia and having a volume of 45 cc. *
  • Sample 1 When mixing the obtained powder and AB, the material obtained when the rotation speed of the ball mill was 800 rpm and the rotation time was 5 hours was designated as Sample 1.
  • the material obtained when the rotation speed of the ball mill was 700 rpm and the rotation time was 5 hours was designated as Sample 2.
  • Sample 3 The material obtained when the rotation speed of the ball mill was 450 rpm and the rotation time was 5 hours was designated as Sample 3.
  • Sample 4 The material obtained when the rotation speed of the ball mill was 200 rpm and the rotation time was 5 hours was designated as Sample 4.
  • Sample 5 was obtained by mixing Li 2 FeSiO 4 and carbon by hand using a mortar for 30 minutes. Each sample was heat-treated.
  • FIGS. 1, 2, 7, 8, and 9 are SEM cross-sectional photographs of materials taken at various magnifications
  • FIGS. 5, 10, and 11 are images of the surface of particles. It is the SEM photograph which was done. *
  • Sample 1 As shown in FIGS. 1 and 2, relatively large large particles having a major axis of about 20 ⁇ m and fine particles having a particle size of about 1 to 4 ⁇ m were mixed. As shown in the lower diagram of FIG. 1 and FIG. 2, a large number of fine particles were uniformly dispersed inside the large particles. That is, the large particles are those in which fine primary particles are combined into secondary particles. As a result of measuring the specific surface area using the BET method, the composite showed a high value of 171.7 m 2 / g.
  • the upper left photograph of FIG. 3 shows an annular dark field scanning transmission electron microscope (ADF-STEM) image of the large secondary particles of Sample 1.
  • ADF-STEM annular dark field scanning transmission electron microscope
  • the mapping of oxygen (O), carbon (C), iron (Fe), and silicon (Si) by an energy dispersive X-ray analyzer (EDX) of secondary particles is shown.
  • the part extending from the center to the left is the site where the secondary particles are present, and the lower right part is the site where the secondary particles are not present.
  • O, C, Fe, and Si were uniformly dispersed in the site where the secondary particles were present. From this, it was found that the secondary particles contain O, C, Fe, and Si as constituent elements. C was also present outside the secondary particles. *
  • the photograph located on the upper left side of FIG. 4 is a transmission electron microscope (TEM) photograph of the secondary particles of Sample 1. From this photograph, it can be seen that the inside of the secondary particles is an aggregate of a plurality of primary particles.
  • the photograph located on the lower left side of FIG. 4 is a photograph obtained by photographing electron diffraction on the circular black box portion of the secondary particles in the upper left TEM photograph. From the figure, since the diffraction line has a halo pattern, it can be seen that the secondary particles are composed of a large number of particles and the size of each particle is small.
  • the structure of Li 2 FeSiO 4 was confirmed, and it was found that the secondary particles contained Li 2 FeSiO 4 .
  • FIG. 5 is a mapping of carbon (C), oxygen (O), silicon (Si), and iron (Fe) in order from the upper side to the lower side of the central portion of FIG. From the figure, all of C, O, Si, and Fe were uniformly dispersed in the portion where the secondary particles were present. About C, it existed also in the part (the upper right part of each photograph) in which secondary particles do not exist. This result was similar to the element mapping by EDX in FIG. *
  • the right side of FIG. 4 shows a mixed image in which the mapping of each element shown in the central part of FIG. 4 is overlaid.
  • the dark color portion indicates carbon (C)
  • the light color portion indicates Fe, Si, and O.
  • the secondary particles contain Li 2 FeSiO 4 , Fe, Si, and O in the light-colored portion are elements constituting Li 2 FeSiO 4 It is. From this figure, it was found that in the secondary particles, Li 2 FeSiO 4 was uniformly dispersed and compounded in carbon to form an active material complex.
  • the light color portion where Li 2 FeSiO 4 exists in the mixed image corresponds to the white or light gray portion of the TEM, and C in the mixed image.
  • the existing dark color portion corresponds to the dark gray or black portion of the TEM.
  • the abundance ratio of CO in the surface layer having a thickness of about 1 ⁇ m It was found to be higher than the abundance ratio of CO.
  • Li 2 FeSiO 4 and carbon are refined and mixed by applying high energy by high-speed rotation, and then they are granulated and bonded together to form an active material composite. After that, it is considered that further refined carbon entered the surface of the active material composite.
  • the reason why the surface layer is rich in oxygen is considered to be due to milling treatment in an air atmosphere.
  • FIG. 5 is a photograph of the appearance of the active material composite taken with a scanning electron microscope (SEM). From the figure, many fine particles having an average particle diameter of about 100 nm were attached to the surface of the active material composite. *
  • the structure of the active material complex is as shown in FIG.
  • the active material composite 10 is composed of a core part 1 and a surface layer 2 covering the surface of the core part 1, and the core part 1 has an average particle size of 10 to 10 made of Li 2 FeSiO 4. 30 nm active material particles 11 are uniformly dispersed in a matrix 12 made of carbon.
  • the surface layer 2 has a thickness of about 1 ⁇ m and constitutes a CO rich layer.
  • the active material particles and the conductive particles were gradually aggregated to form aggregates, but a hollow portion remained in the aggregates. There were various sizes. For this reason, it cannot be said that the active material particles and the conductive particles are bonded to each other in a finely dispersed state.
  • the specific surface area of the aggregate was 130.7 m 2 / g.
  • Sample 4 was not posted with SEM photographs, but was observed with SEM.
  • the active material particles and the conductive particles were mixed by being smaller than the particle size before mixing.
  • the active material particles and the conductive particles were mixed as they were primary particles, and secondary particles were not formed.
  • the specific surface area of this mixture was 59.3 m 2 / g.
  • sample 5 As shown in FIG. 11, active material particles having an average particle diameter of 1000 nm (particulate white portions) and conductive particles having an average particle diameter of 100 nm (fluffy light gray portions) were mixed. . Each particle had the same shape and size before mixing and was not agglomerated. *
  • the battery using Sample 1 had a significantly larger discharge capacity at the second cycle than the batteries using Samples 2 to 4.
  • the discharge capacity of the sample 1 battery is 1.2 times the discharge capacity of the sample 2 battery, 1.6 times the discharge capacity of the sample 3 battery, and 2 times the discharge capacity of the sample 4 battery. .2 times. From this, it was found that the charge / discharge capacity was improved by increasing the milling speed, and in particular, the charge / discharge capacity was significantly improved by setting the milling speed to 800 rpm as in Sample 1. *
  • the battery of Sample 1 is 42 No significant reduction in discharge capacity was observed until the cycle. From this, it was found that the battery of Sample 1 was excellent in cycle characteristics.
  • a rate characteristic test of the coin battery prepared using Sample 1 was performed.
  • the test conditions were as follows: discharge rate 0.1C at 1-5th cycle, 0.2C at 6-10th cycle, 0.5C at 11-15th cycle, 1C at 16-20th cycle, 21-25th cycle 2C for the eyes, 5C for the 26th to 30th cycles, 0.1C for the 31st to 55th cycles, and the rate during charging was kept constant at 0.1C.
  • the test was conducted at 30 ° C. The test results are shown in FIG. *
  • the discharge capacity at 1C was 200 mAh / g
  • the discharge capacity at 5C was 170 mAh / g
  • excellent rate characteristics were exhibited.
  • reaction resistance The reaction resistance of the materials of Samples 1 and 3 was measured.
  • the test of the reaction resistance was performed on each battery after charging and discharging using a measuring device (trade name: SI 1280B, manufactured by Solartron) using an AC impedance method.
  • the amplitude of the alternating current at the time of measurement was set to 10 mV, the maximum value of the frequency was 20 kHz, and the minimum value was 0.1 Hz.
  • the charging condition was a constant voltage charging at 4.8V for 10 hours, and the discharging condition was a constant current discharging at 1.5V. *
  • FIGS. FIG. 18 shows the reaction resistance of each material after charging
  • FIG. 19 shows the reaction resistance of each material after discharging.
  • the horizontal axis indicates the real axis of the impedance resistance
  • the vertical axis indicates the imaginary axis of the impedance resistance.
  • the width between both ends of the arc-shaped portion indicates the reaction resistance inside the particle and at the particle interface included in each material, and the resistance having a larger real part than the arc-shaped portion. The part shows the diffusion resistance outside the particle.
  • the reaction resistance of the material of Sample 1 was about one-fourth that of Sample 3. This is a factor that the initial discharge capacity of the battery manufactured using the material of Sample 1 as the positive electrode active material is larger than that of Sample 3.
  • the reaction resistance (impedance) of each material indicates the resistance inside the particle contained in each material and at the particle interface.
  • the impedance decreases as the particle size of the active material particles decreases, and the reaction resistance tends to decrease as the contact area with the conductive particles at the active material particle interface increases.
  • the active material particles are as fine as an average particle size of 100 nm or less, and the conductive particles are also as fine as an average particle size of 100 nm or less, and these particles are uniformly dispersed.
  • the active material particles and the conductive particles are in close contact with each other, and the contact area is large. For this reason, the reaction resistance of the sample 1 becomes small, and it is estimated that the battery produced using this as a positive electrode active material has a large discharge capacity.
  • the active material complexes of Samples 6 to 8 were manufactured by the following method.
  • the active material composites of Samples 6 to 8 are composed of Li 2 MnSiO 4 and carbon.
  • Lithium silicate compound Li 2 SiO 3 (lithium silicate, manufactured by Kishida Chemical Co., Ltd., purity 99.5%) 0.03 mol and manganese oxalate (Kishida Chemical Co., Ltd., purity 99.9%) 0.03 mol 20 ml of acetone was added to the mixture and mixed with a zirconia ball mill at 500 rpm for 60 minutes and dried. This was mixed with the carbonate mixture.
  • the carbonate mixture consists of lithium carbonate (Kishida Chemical Co., Ltd., purity 99.9%), sodium carbonate (Kishida Chemical Co., Ltd., purity 99.5%), and potassium carbonate (Kishida Chemical Co., Ltd., purity 99.5%).
  • the obtained powder was heated in a gold crucible and heated to 500 ° C. in an electric furnace in a mixed gas atmosphere of carbon dioxide (flow rate: 100 mL / min) and hydrogen (flow rate: 3 mL / min).
  • the mixture was reacted for 13 hours in a molten state of the carbonate mixture.
  • the entire reactor core as a reaction system was taken out from the electric furnace and rapidly cooled to room temperature through a mixed gas.
  • FIG. 20 is an SEM photograph of active material particles made of Li 2 MnSiO 4 .
  • the active material particles immediately after synthesis are in the form of flakes and distributed in a particle size of 0.5 to 3 ⁇ m.
  • the average particle size was 0.7 ⁇ m.
  • the specific surface area was 12.5 m 2 / g.
  • the obtained active material particles and acetylene black (AB, average particle size 0.3 ⁇ m) were mixed at a mass ratio of 5: 4.
  • the mixture is mechanically milled under the following predetermined conditions in an air atmosphere using a mechanical milling device (French Japan Co., Ltd., planetary ball mill P-7). Energized. This step was performed by putting 50 g of ⁇ 4 mm zirconia balls and 300 mg of the mixture in a ball mill grinding container made of zirconia and having a volume of 45 cc. *
  • FIG. 21 is a SEM (Scanning Electron Microscope) photograph of Sample 6.
  • relatively large large particles having a major axis of about 10 ⁇ m and fine particles having a particle size of about 0.5 to 5 ⁇ m were mixed. Inside these particles, many fine particles were uniformly dispersed. Large particles are secondary particles obtained by compositing fine primary particles.
  • the large particles were Li 2 MnSiO 4 / C composites in which Li 2 MnSiO 4 having a particle size of 10 to 50 nm and carbon having a particle size of 10 to 50 nm were bonded together to form a composite.
  • this composite showed a high value of 170.2 m 2 / g.
  • the active material particles and the conductive particles were mixed in a size larger than that of Sample 6.
  • the active material particles and the conductive particles are gradually aggregated to form aggregates.
  • the average particle diameter of the aggregates is about 1000 nm, which is smaller than the secondary particles of the sample 6, and has a hollow portion inside. was there.
  • the sizes of the active material particles and the conductive particles varied, and the active material particles and the conductive particles were dispersed unevenly. Further, as a result of measuring the specific surface area using the BET method, this complex showed 101 m 2 / g.
  • FIG. 23 shows XRD patterns of Li 2 MnSiO 4 immediately after synthesis and samples 6 to 8. As shown in FIG. 23, the intensity of the diffraction peak is lower in Sample 6 than in Samples 7 and 8. This is presumed to be due to a decrease in crystallinity and finer particles.
  • Sample 7 was a Li 2 MnSiO 4 / C composite in which Li 2 MnSiO 4 having a particle size of 400 nm and carbon having a particle size of 240 nm were bonded together to form a composite.
  • the specific surface area of Sample 7 was 115 m 2 / g.
  • Sample 8 was a Li 2 MnSiO 4 / C composite in which Li 2 MnSiO 4 having a particle diameter of 500 nm and carbon having a particle diameter of 300 nm were bonded to each other to form a composite.
  • the specific surface area of Sample 7 was 101 m 2 / g.
  • Each positive electrode active material Li 2 MnSiO 4 / C composite
  • AB acetylene black
  • PTFE polytetrafluoroethylene
  • a polypropylene membrane (Celgard 2400, manufactured by Celgard) and a glass filter were used as the separator. Lithium metal foil was used as the negative electrode. From these, a coin-type half battery was produced.
  • the battery using the sample 6 has an initial charge capacity, an initial discharge capacity, an initial efficiency, and an initial discharge average voltage, as compared with the battery using the samples 7 and 8. High value was shown.
  • the initial discharge capacity of the sample 6 battery was 2.6 times the initial discharge capacity of the sample 7 battery and 2.7 times the discharge capacity of the sample 8 battery.
  • the initial efficiency of the sample 6 battery was 1.2 times the initial efficiency of the sample 7 battery and 1.4 times the initial efficiency of the sample 8 battery.
  • the initial discharge average voltage of the sample 6 battery was 0.1 V higher than the initial discharge average voltage of the sample 7 battery, and 0.2 V higher than the initial discharge average voltage of the sample 8 battery. From this, it was found that the charge / discharge capacity, the initial efficiency, and the average discharge voltage are improved by increasing the milling speed and milling time.
  • the active material particles are as fine as an average particle size of 100 nm or less, and the conductive particles are as fine as an average particle size of 100 nm or less, and these particles are uniformly dispersed. Further, in the portion where the active material composite is formed, the active material particles and the conductive particles are in close contact with each other, and the contact area is large. For this reason, the reaction resistance of the sample 6 becomes small, and it is estimated that the battery produced using this as a positive electrode active material has a large discharge capacity.
  • the nanoparticles as described above are uniformly dispersed, a lithium ion conductive path is well formed, so that lithium ions released from the active material at the time of charging easily return at the time of discharging. For this reason, it is estimated that the initial efficiency of the sample 6 has improved. Furthermore, it is presumed that due to the reduced reaction resistance, the charge / discharge curve inherent to the active material was obtained, leading to an improvement in the discharge average voltage.

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Abstract

La présente invention concerne un matériau actif d'électrode positive pour batteries secondaires à électrolyte non aqueux qui s'obtient en liant des particules de matériau actif, qui sont formées d'un matériau actif et ont un diamètre particulaire moyen de 100 nm ou moins, et des particules conductrices, qui sont formées d'un matériau conducteur et ont un diamètre particulaire moyen de 100 nm ou moins, les unes aux autres. Ledit matériau actif d'électrode positive pour batteries secondaires à électrolyte non aqueux a une surface spécifique de 150 m2/g ou plus.
PCT/JP2013/001242 2012-02-28 2013-02-28 Composé de matériau actif, son procédé de production, matériau actif d'électrode positive pour batteries secondaires à électrolyte non aqueux, et batterie secondaire à électrolyte non aqueux WO2013128936A1 (fr)

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JP2015008102A (ja) * 2013-06-26 2015-01-15 日亜化学工業株式会社 オリビン型ケイ酸遷移金属リチウム化合物およびその製造方法
WO2016143171A1 (fr) * 2015-03-09 2016-09-15 太平洋セメント株式会社 Substance active pour électrode positive destinée à une batterie secondaire et son procédé de production
JP2016171057A (ja) * 2015-03-09 2016-09-23 太平洋セメント株式会社 二次電池用正極活物質及びその製造方法
WO2016151891A1 (fr) * 2015-03-26 2016-09-29 太平洋セメント株式会社 Matière active d'électrode positive pour batterie secondaire, et procédé de fabrication de celle-ci
WO2016151890A1 (fr) * 2015-03-24 2016-09-29 太平洋セメント株式会社 Matière active d'électrode positive pour batterie secondaire, et procédé de fabrication de celle-ci
JP2016181496A (ja) * 2015-03-24 2016-10-13 太平洋セメント株式会社 二次電池用正極活物質及びその製造方法
JP2016184570A (ja) * 2015-03-26 2016-10-20 太平洋セメント株式会社 二次電池用正極活物質及びその製造方法
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JP2020105053A (ja) * 2018-12-27 2020-07-09 株式会社オキサイド リチウム金属リン酸塩の製造方法、リチウム金属リン酸塩、リチウムイオン二次電池の正極材料、リチウムイオン二次電池
WO2020203997A1 (fr) * 2019-03-29 2020-10-08 日本ゼオン株式会社 Matériau de moulage pour électrode, électrode, procédé de fabrication ainsi que procédé de recyclage d'électrode, et et dispositif électrochimique
US10964950B2 (en) 2015-03-26 2021-03-30 Taiheiyo Cement Corporation Secondary battery positive-electrode active material and method for producing same

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2018179969A1 (fr) * 2017-03-29 2018-10-04 パナソニックＩｐマネジメント株式会社 Matériau d'électrode négative pour batterie secondaire à électrolytique non aqueux et batterie secondaire à électrolyte non aqueux

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2009062256A (ja) * 2007-08-10 2009-03-26 Tokyo Institute Of Technology 無機物粒子の製造方法
JP2009539739A (ja) * 2006-02-28 2009-11-19 プリメット プレシジョン マテリアルズ， インコーポレイテッド リチウムから作られた化合物のナノ粒子組成物および該ナノ粒子組成物を形成する方法
JP2010219048A (ja) * 2009-03-12 2010-09-30 Belenos Clean Power Holding Ag 開放多孔質電気伝導性ナノ複合材料
JP2010218830A (ja) * 2009-03-16 2010-09-30 Tdk Corp 活物質、これを含む電極、当該電極を含むリチウムイオン二次電池、及び活物質の製造方法
JP2010251194A (ja) * 2009-04-17 2010-11-04 Toyota Motor Corp 電池用正極及びその製造方法
JP2011517053A (ja) * 2008-04-14 2011-05-26 ダウ グローバル テクノロジーズ リミティド ライアビリティ カンパニー 二次リチウム電池用の陰極活性材料としてのリン酸マンガンリチウム／炭素ナノ複合材
JP2011181331A (ja) * 2010-03-01 2011-09-15 Furukawa Electric Co Ltd:The 正極活物質材料、正極、２次電池及びこれらの製造方法
JP2011249324A (ja) * 2010-04-28 2011-12-08 Semiconductor Energy Lab Co Ltd 蓄電装置用正極活物質、蓄電装置、及び電気推進車両、並びに蓄電装置の作製方法

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2009539739A (ja) * 2006-02-28 2009-11-19 プリメット プレシジョン マテリアルズ， インコーポレイテッド リチウムから作られた化合物のナノ粒子組成物および該ナノ粒子組成物を形成する方法
JP2009062256A (ja) * 2007-08-10 2009-03-26 Tokyo Institute Of Technology 無機物粒子の製造方法
JP2011517053A (ja) * 2008-04-14 2011-05-26 ダウ グローバル テクノロジーズ リミティド ライアビリティ カンパニー 二次リチウム電池用の陰極活性材料としてのリン酸マンガンリチウム／炭素ナノ複合材
JP2010219048A (ja) * 2009-03-12 2010-09-30 Belenos Clean Power Holding Ag 開放多孔質電気伝導性ナノ複合材料
JP2010218830A (ja) * 2009-03-16 2010-09-30 Tdk Corp 活物質、これを含む電極、当該電極を含むリチウムイオン二次電池、及び活物質の製造方法
JP2010251194A (ja) * 2009-04-17 2010-11-04 Toyota Motor Corp 電池用正極及びその製造方法
JP2011181331A (ja) * 2010-03-01 2011-09-15 Furukawa Electric Co Ltd:The 正極活物質材料、正極、２次電池及びこれらの製造方法
JP2011249324A (ja) * 2010-04-28 2011-12-08 Semiconductor Energy Lab Co Ltd 蓄電装置用正極活物質、蓄電装置、及び電気推進車両、並びに蓄電装置の作製方法

Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2015008102A (ja) * 2013-06-26 2015-01-15 日亜化学工業株式会社 オリビン型ケイ酸遷移金属リチウム化合物およびその製造方法
TWI670894B (zh) * 2015-03-09 2019-09-01 日商太平洋水泥股份有限公司 二次電池用正極活性物質及其製造方法
WO2016143171A1 (fr) * 2015-03-09 2016-09-15 太平洋セメント株式会社 Substance active pour électrode positive destinée à une batterie secondaire et son procédé de production
JP2016171057A (ja) * 2015-03-09 2016-09-23 太平洋セメント株式会社 二次電池用正極活物質及びその製造方法
US11646405B2 (en) 2015-03-09 2023-05-09 Taiheiyo Cement Corporation Positive electrode active substance for secondary cell and method for producing same
WO2016151890A1 (fr) * 2015-03-24 2016-09-29 太平洋セメント株式会社 Matière active d'électrode positive pour batterie secondaire, et procédé de fabrication de celle-ci
JP2016181496A (ja) * 2015-03-24 2016-10-13 太平洋セメント株式会社 二次電池用正極活物質及びその製造方法
US10601042B2 (en) 2015-03-24 2020-03-24 Taiheiyo Cement Corporation Secondary battery positive electrode active material and method for producing same
WO2016151891A1 (fr) * 2015-03-26 2016-09-29 太平洋セメント株式会社 Matière active d'électrode positive pour batterie secondaire, et procédé de fabrication de celle-ci
US10964950B2 (en) 2015-03-26 2021-03-30 Taiheiyo Cement Corporation Secondary battery positive-electrode active material and method for producing same
JP2016184570A (ja) * 2015-03-26 2016-10-20 太平洋セメント株式会社 二次電池用正極活物質及びその製造方法
JP2016186932A (ja) * 2015-03-27 2016-10-27 太平洋セメント株式会社 二次電池用正極活物質及びその製造方法
JP2020105053A (ja) * 2018-12-27 2020-07-09 株式会社オキサイド リチウム金属リン酸塩の製造方法、リチウム金属リン酸塩、リチウムイオン二次電池の正極材料、リチウムイオン二次電池
JP7164178B2 (ja) 2018-12-27 2022-11-01 株式会社オキサイド リチウム金属リン酸塩、リチウムイオン二次電池の正極材料、リチウムイオン二次電池
WO2020203997A1 (fr) * 2019-03-29 2020-10-08 日本ゼオン株式会社 Matériau de moulage pour électrode, électrode, procédé de fabrication ainsi que procédé de recyclage d'électrode, et et dispositif électrochimique

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