WO2023008006A1 - 正極材料、正極、および電池 - Google Patents
正極材料、正極、および電池 Download PDFInfo
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- WO2023008006A1 WO2023008006A1 PCT/JP2022/025014 JP2022025014W WO2023008006A1 WO 2023008006 A1 WO2023008006 A1 WO 2023008006A1 JP 2022025014 W JP2022025014 W JP 2022025014W WO 2023008006 A1 WO2023008006 A1 WO 2023008006A1
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- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/05—Accumulators with non-aqueous electrolyte
- H01M10/056—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes
- H01M10/0561—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes the electrolyte being constituted of inorganic materials only
- H01M10/0562—Solid materials
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- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
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- H01M10/00—Secondary cells; Manufacture thereof
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- H01M10/052—Li-accumulators
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- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/05—Accumulators with non-aqueous electrolyte
- H01M10/052—Li-accumulators
- H01M10/0525—Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
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- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
- H01M4/131—Electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx
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- H01M4/36—Selection of substances as active materials, active masses, active liquids
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- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/36—Selection of substances as active materials, active masses, active liquids
- H01M4/362—Composites
- H01M4/366—Composites as layered products
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- 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
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- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/36—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
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- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
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- H—ELECTRICITY
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- 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
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- H—ELECTRICITY
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- H01M2300/00—Electrolytes
- H01M2300/0017—Non-aqueous electrolytes
- H01M2300/0065—Solid electrolytes
- H01M2300/0068—Solid electrolytes inorganic
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- H—ELECTRICITY
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- H01M2300/00—Electrolytes
- H01M2300/0017—Non-aqueous electrolytes
- H01M2300/0065—Solid electrolytes
- H01M2300/0068—Solid electrolytes inorganic
- H01M2300/0071—Oxides
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/10—Energy storage using batteries
Definitions
- the present disclosure relates to cathode materials, cathodes, and batteries.
- Patent Document 1 discloses a method for producing an active material in which a positive electrode active material is coated with an oxide-based solid electrolyte and further coated with a sulfide-based solid electrolyte, and a battery using the same.
- the positive electrode material of the present disclosure is a positive electrode active material; a first solid electrolyte; a second solid electrolyte; with the first solid electrolyte contains Li, Zr, M, and X; M is at least one selected from the group consisting of metal elements other than Li and metalloid elements, X is at least one selected from the group consisting of F, Cl, Br, and I;
- the second solid electrolyte has a composition different from that of the first solid electrolyte, A ratio of the volume of the first solid electrolyte to the total volume of the first solid electrolyte and the second solid electrolyte is 3% or more and 60% or less.
- the safety of batteries can be improved.
- FIG. 1 is a cross-sectional view showing a schematic configuration of a positive electrode material according to Embodiment 1.
- FIG. FIG. 2 is a cross-sectional view showing a schematic configuration of a modification of the positive electrode material according to Embodiment 1.
- FIG. FIG. 3 is a cross-sectional view showing a schematic configuration of a battery according to Embodiment 2.
- Batteries with solid electrolytes are recognized as safe, but this is not always the case.
- oxygen may be generated from the positive electrode active material.
- the generated oxygen oxidizes the solid electrolyte and raises the temperature of the battery.
- the container of the battery is deteriorated and damaged, or that the battery malfunctions. Therefore, it is expected that the safety of batteries using solid electrolytes will be further improved.
- the positive electrode material according to the first aspect of the present disclosure is a positive electrode active material; a first solid electrolyte; a second solid electrolyte; with the first solid electrolyte contains Li, Zr, M, and X; M is at least one selected from the group consisting of metal elements other than Li and metalloid elements, X is at least one selected from the group consisting of F, Cl, Br, and I;
- the second solid electrolyte has a composition different from that of the first solid electrolyte, A ratio of the volume of the first solid electrolyte to the total volume of the first solid electrolyte and the second solid electrolyte is 3% or more and 60% or less.
- the safety of the battery can be improved.
- the ratio of the volume of the first solid electrolyte to the total volume of the first solid electrolyte and the second solid electrolyte is 3.3. % or more and 50% or less. According to the positive electrode material of the second aspect, it is possible to further improve the safety of the battery.
- the ratio of the volume of the first solid electrolyte to the total volume of the first solid electrolyte and the second solid electrolyte is 6.7. % or more and 50% or less. According to the positive electrode material of the third aspect, it is possible to further improve the safety of the battery.
- the ratio of the volume of the first solid electrolyte to the total volume of the first solid electrolyte and the second solid electrolyte is 33% or more. , and may be 50% or less. According to the positive electrode material of the fourth aspect, it is possible to further improve the safety of the battery.
- the ratio of the volume of the first solid electrolyte to the total volume of the first solid electrolyte and the second solid electrolyte is 3.3. % or more and 8.0% or less. According to the positive electrode material of the fifth aspect, it is possible to further improve the safety of the battery.
- the second solid electrolyte may contain Li and S.
- a sulfide solid electrolyte has high ionic conductivity and can improve the charge-discharge efficiency of a battery.
- sulfide solid electrolytes may be inferior in oxidation resistance.
- M may contain aluminum.
- the first solid electrolyte exhibits high ionic conductivity.
- the first solid electrolyte may be represented by the following compositional formula (1), ⁇ , ⁇ , ⁇ and ⁇ may each independently be a value greater than zero.
- the output characteristics of the battery can be improved.
- the positive electrode active material according to any one of the first to eighth aspects may have a coating layer on at least part of the surface. According to such a configuration, it is possible to improve the charging and discharging efficiency of the battery.
- the coating layer may contain an oxide solid electrolyte having lithium ion conductivity.
- oxide solid electrolyte By using the oxide solid electrolyte as the coating layer, the charge/discharge efficiency of the battery can be further improved.
- the coating layer may contain lithium niobate. According to such a configuration, it is possible to improve the charging and discharging efficiency of the battery.
- a positive electrode according to the twelfth aspect of the present disclosure includes the positive electrode material according to any one of the first to eleventh aspects. With such a configuration, the safety of the battery can be improved.
- a battery according to the thirteenth aspect of the present disclosure includes the positive electrode of the twelfth aspect. According to the present disclosure, battery safety can be improved.
- FIG. 1 is a cross-sectional view showing a schematic configuration of a positive electrode material according to Embodiment 1.
- FIG. Cathode material 10 includes cathode active material 100 , first solid electrolyte 101 , and second solid electrolyte 102 .
- the first solid electrolyte contains Li, Zr, M, and X.
- M is at least one selected from the group consisting of metal elements other than Li and Zr and metalloid elements.
- X is at least one selected from the group consisting of F, Cl, Br and I;
- the ratio V1/Vt of the volume V1 of the first solid electrolyte to the total volume Vt of the first solid electrolyte 101 and the second solid electrolyte 102 is 3% or more and 60% or less, expressed as a percentage. is.
- “Semimetallic elements” include B, Si, Ge, As, Sb, and Te.
- Metallic element means all elements contained in Groups 1 to 12 of the periodic table, except hydrogen, and B, Si, Ge, As, Sb, Te, C, N, P, O, S, and Se. Including all elements contained in Groups 13 to 16, except That is, the metal element is a group of elements that can become a cation when forming an inorganic compound with a halogen element.
- the first solid electrolyte can be a halogen-containing solid electrolyte, a so-called halide solid electrolyte.
- Halide solid electrolytes have excellent oxidation resistance. Therefore, by mixing the first solid electrolyte, oxidation of the positive electrode (for example, oxidation of the second solid electrolyte) can be suppressed. Thereby, the heat generation of the battery using the positive electrode material 10 is suppressed, and the safety of the battery using the positive electrode material 10 can be improved.
- the ratio V1/Vt may be 3.3% or more, 6% or more, or 6.7% or more. If the above ratio V1/Vt is too high, there is concern that the ionic conductivity of the positive electrode material 10 will be insufficient.
- the ratio V1/Vt may desirably be 50% or less, or 40% or less.
- the ratio V1/Vt may be, for example, 3.3% or more and 50% or less.
- the ratio V1/Vt may be 6.7% or more and 50% or less, or 33% or more and 50% or less. good.
- the above ratio V1/Vt may be 3.3% or more and 8.0% or less.
- the total volume Vt of the first solid electrolyte 101 and the second solid electrolyte 102 is the sum of the volume V1 of the first solid electrolyte 101 and the volume V2 of the second solid electrolyte 102.
- the volume V1 of the first solid electrolyte 101 is the total volume of the first solid electrolyte 101 in the positive electrode material 10 powder.
- the volume V2 of the second solid electrolyte 102 is the total volume of the second solid electrolyte 102 in the positive electrode material 10 powder. That is, the above ratio V1/Vt is a value obtained from a certain amount of powder of the positive electrode material 10 as a whole.
- the above ratio V1/Vt can be calculated from the charged amount of materials, and can also be calculated by the method described below. That is, a cross section of a positive electrode using the positive electrode material 10 is observed with a scanning electron microscope (SEM-EDX) to obtain a two-dimensional mapping image of elements.
- the measurement conditions of the scanning electron microscope for acquiring the two-dimensional mapping image are, for example, a magnification of 1000 times to 3000 times and an acceleration voltage of 5 kV.
- a two-dimensional mapping image is acquired at a resolution of 1280 ⁇ 960.
- the two-dimensional mapping image of the element is analyzed, and the volume of the positive electrode active material 100 and the volume of the first solid electrolyte 101 are obtained from the number of pixels of the element contained in each of the positive electrode active material 100, the first solid electrolyte 101, and the second solid electrolyte 102.
- V1 and the volume V2 of the second solid electrolyte 102 can be specified.
- the ratio "v1:100-v1" between the volume of the positive electrode active material 100 and the volume of the solid electrolyte may satisfy 30 ⁇ v1 ⁇ 95.
- 30 ⁇ v1 the energy density of the battery is sufficiently ensured.
- v1 ⁇ 95 the battery can operate at high power.
- “Volume of solid electrolyte” is the total volume of first solid electrolyte 101 and second solid electrolyte 102 .
- the positive electrode active material 100 includes a material that has the property of intercalating and deintercalating metal ions (eg, lithium ions).
- metal ions eg, lithium ions
- As the positive electrode active material 100 lithium-containing transition metal oxides, transition metal fluorides, polyanion materials, fluorinated polyanion materials, transition metal sulfides, transition metal oxysulfides, transition metal oxynitrides, and the like can be used.
- a lithium-containing transition metal oxide when a lithium-containing transition metal oxide is used as the positive electrode active material 100, the manufacturing cost of the battery can be reduced and the average discharge voltage can be increased.
- Lithium-containing transition metal oxides include Li(NiCoAl)O 2 , Li(NiCoMn)O 2 and LiCoO 2 .
- the positive electrode active material 100 has, for example, a particle shape.
- the shape of the particles of the positive electrode active material 100 is not particularly limited.
- the shape of the particles of the positive electrode active material 100 may be spherical, oval, scaly, or fibrous.
- the median diameter of the positive electrode active material 100 may be 0.1 ⁇ m or more and 100 ⁇ m or less.
- the median diameter of the positive electrode active material 100 is 0.1 ⁇ m or more, the positive electrode active material 100, the first solid electrolyte 101, and the second solid electrolyte 102 can form a good dispersion state. As a result, the charge/discharge characteristics of the battery are improved.
- the median diameter of the positive electrode active material 100 is 100 ⁇ m or less, the diffusion rate of lithium inside the positive electrode active material 100 is sufficiently ensured. Therefore, the battery can operate at high output.
- the median diameter of the positive electrode active material 100 may be larger than the median diameters of the first solid electrolyte 101 and the second solid electrolyte 102 . Thereby, the positive electrode active material 100, the first solid electrolyte 101 and the second solid electrolyte 102 can form a good dispersion state.
- volume diameter means the particle diameter when the cumulative volume in the volume-based particle size distribution is equal to 50%.
- the volume-based particle size distribution is measured by, for example, a laser diffraction measurement device or an image analysis device.
- the first solid electrolyte 101 has, for example, ionic conductivity.
- the ionic conductivity is typically lithium ion conductivity.
- Raw materials of the first solid electrolyte 101, by-products generated when manufacturing the first solid electrolyte 101, and the like are included in the unavoidable impurities.
- the mass ratio of the inevitable impurities to the mass of the entire first solid electrolyte 101 may be 5% or less, 3% or less, 1% or less, or 0.5% or less. may be
- the first solid electrolyte 101 is a material containing Li, Zr, M, and X. M and X are as described above. Such materials have good ionic conductivity and oxidation resistance. Therefore, the battery using the positive electrode material having the first solid electrolyte 101 improves the charge/discharge efficiency of the battery and the thermal stability of the battery.
- a halide solid electrolyte as the first solid electrolyte 101 is represented, for example, by the following compositional formula (1).
- composition formula (1) ⁇ , ⁇ , ⁇ and ⁇ are each independently a value greater than 0. Li ⁇ Zr ⁇ M ⁇ X ⁇ Formula (1)
- the halide solid electrolyte represented by the compositional formula (1) has higher ionic conductivity than a halide solid electrolyte such as LiI, which consists only of Li and a halogen element. Therefore, when the halide solid electrolyte represented by the compositional formula (1) is used in a battery, the charge/discharge efficiency of the battery can be improved.
- the halide solid electrolyte may consist essentially of Li, Zr, Al, and X.
- the halide solid electrolyte consists essentially of Li, Zr, Al, and X
- the halide solid electrolyte consists essentially of Li, Zr, Al, and X
- Li, Zr, Al, and X that is, the molar fraction
- the molar ratio ie, mole fraction
- the halide solid electrolyte may consist of Li, Zr, Al, and X only.
- the ratio of the amount of Li substance to the total amount of Zr and Al may be 1.12 or more and 5.07 or less.
- the halide solid electrolyte may be represented by the following compositional formula (2). Li6-(4-x)b ( Zr1 - xAlx) bF6 ... Formula (2)
- the formula: 0.01 ⁇ x ⁇ 0.99 may be satisfied in formula (2).
- the formula: 0.2 ⁇ x ⁇ 0.95 may be satisfied.
- the upper and lower limits of the range of x in equation (2) are 0.01, 0.2, 0.4, 0.5, 0.5, 0.7, 0.8, 0.95, and 0 It can be defined by any combination of numbers selected from 0.99.
- the formula: 0.7 ⁇ b ⁇ 1.3 may be satisfied in formula (2).
- the formula: 0.9 ⁇ b ⁇ 1.04 may be satisfied.
- the upper and lower limits of the range of b in formula (2) are 0.7, 0.8, 0.9, 0.96, 1, 1.04, 1.1, 1.2, and 1.3. can be defined by any combination selected from the numerical values of
- the halide solid electrolyte may be crystalline or amorphous.
- the shape of the halide solid electrolyte is not limited. Examples of such shapes are acicular, spherical, or ellipsoidal.
- the halide solid electrolyte may be particles.
- the solid electrolyte When the shape of the halide solid electrolyte is, for example, particulate (eg, spherical), the solid electrolyte may have a median diameter of 0.1 ⁇ m or more and 100 ⁇ m or less.
- Median size means the particle size when the cumulative volume in a volume-based particle size distribution is equal to 50%.
- the volume-based particle size distribution is measured by, for example, a laser diffraction measurement device or an image analysis device.
- the halide solid electrolyte may be a solid electrolyte that does not contain sulfur. In this case, generation of sulfur-containing gas such as hydrogen sulfide gas from the solid electrolyte can be avoided.
- a solid electrolyte containing no sulfur means a solid electrolyte represented by a composition formula containing no elemental sulfur. Therefore, a solid electrolyte containing a very small amount of sulfur, for example a solid electrolyte having a sulfur content of 0.1% by mass or less, belongs to the solid electrolyte containing no sulfur.
- the halide solid electrolyte may further contain oxygen as an anion other than the halogen element.
- a halide solid electrolyte as the first solid electrolyte can be produced, for example, by the following method.
- the raw material powder is prepared and mixed to achieve the desired composition.
- the raw material powder may be, for example, a halide.
- the desired composition is Li2.64Zr0.48Al0.48F6
- LiF , ZrF4 , and AlF3 are mixed in a molar ratio of the order of 2.64 :0.48:0.48.
- the raw material powders may be mixed in pre-adjusted molar ratios to compensate for possible compositional changes in the synthesis process.
- the raw material powders are mechanochemically reacted with each other in a mixing device such as a planetary ball mill (that is, using the method of mechanochemical milling) to obtain a reactant.
- the reactants may be fired in vacuum or in an inert atmosphere.
- a mixture of raw material powders may be fired in vacuum or in an inert atmosphere to obtain a reactant. Firing is preferably performed at, for example, 100° C. or higher and 400° C. or lower for 1 hour or longer.
- the raw material powder is preferably fired in a sealed container such as a quartz tube.
- a halide solid electrolyte can be obtained by these methods.
- the second solid electrolyte 102 may contain at least one selected from the group consisting of halide solid electrolytes, sulfide solid electrolytes, oxide solid electrolytes, polymer solid electrolytes, and complex hydride solid electrolytes.
- the halide solid electrolyte examples include the materials previously described as the first solid electrolyte 101 .
- the second solid electrolyte 102 has a composition different from that of the first solid electrolyte 101 .
- the different composition means a composition in which the constituent elements do not match, or a composition in which the ratio of the constituent elements differs even when the constituent elements match.
- An oxide solid electrolyte is a solid electrolyte containing oxygen.
- the oxide solid electrolyte may further contain anions other than sulfur and halogen elements as anions other than oxygen.
- oxide solid electrolytes examples include NASICON solid electrolytes typified by LiTi 2 (PO 4 ) 3 and element-substituted products thereof, (LaLi)TiO 3 -based perovskite solid electrolytes, Li 14 ZnGe 4 O 16 , Li LISICON solid electrolytes typified by 4 SiO 4 , LiGeO 4 and elemental substitutions thereof, garnet type solid electrolytes typified by Li 7 La 3 Zr 2 O 12 and elemental substitutions thereof, Li 3 PO 4 and its N Glass or glass-ceramics obtained by adding materials such as Li 2 SO 4 and Li 2 CO 3 to base materials containing Li—BO compounds such as substitutes, LiBO 2 and Li 3 BO 3 may be used.
- a compound of a polymer compound and a lithium salt can be used.
- the polymer compound may have an ethylene oxide structure.
- a polymer compound having an ethylene oxide structure can contain a large amount of lithium salt. Therefore, the ionic conductivity can be further increased.
- Lithium salts include LiPF6 , LiBF4 , LiSbF6 , LiAsF6 , LiSO3CF3 , LiN ( SO2F ) 2 , LiN ( SO2CF3 ) 2 , LiN ( SO2C2F5 ) 2 , LiN( SO2CF3 )( SO2C4F9 ) , LiC ( SO2CF3 ) 3 etc. are mentioned.
- One lithium salt selected from these may be used alone, or a mixture of two or more lithium salts selected from these may be used.
- LiBH 4 --LiI LiBH 4 --P 2 S 5 or the like
- LiBH 4 --LiI LiBH 4 --P 2 S 5 or the like
- the second solid electrolyte 102 may contain Li and S.
- the second solid electrolyte 102 may contain a sulfide solid electrolyte.
- a sulfide solid electrolyte has high ionic conductivity and can improve the charge-discharge efficiency of a battery.
- sulfide solid electrolytes may be inferior in oxidation resistance.
- Examples of sulfide solid electrolytes include Li 2 SP 2 S 5 , Li 2 S—SiS 2 , Li 2 S—B 2 S 3 , Li 2 S—GeS 2 , Li 3.25 Ge 0.25 P 0.75 S 4 , Li 10 GeP 2 S 12 and the like can be used.
- LiX , Li2O , MOq , LipMOq , etc. may be added to these.
- X in “LiX” is at least one selected from the group consisting of F, Cl, Br and I.
- the element M in “MO q " and “Li p MO q " is at least one selected from the group consisting of P, Si, Ge, B, Al, Ga, In, Fe, and Zn.
- p and q in "MO q " and "L p MO q " are independent natural numbers.
- the second solid electrolyte 102 may contain two or more of the materials listed as solid electrolytes.
- the second solid electrolyte 102 may contain, for example, a halide solid electrolyte and a sulfide solid electrolyte.
- the second solid electrolyte 102 may have lithium ion conductivity higher than the lithium ion conductivity of the first solid electrolyte 101 .
- the second solid electrolyte 102 may contain unavoidable impurities such as starting materials, by-products, and decomposition products used when synthesizing the solid electrolyte. This also applies to the first solid electrolyte 101 .
- the positive electrode material 10 may contain a binder for the purpose of improving adhesion between particles.
- a binder is used to improve the binding properties of the material forming the positive electrode.
- Binders include polyvinylidene fluoride, polytetrafluoroethylene, polyethylene, polypropylene, aramid resin, polyamide, polyimide, polyamideimide, polyacrylonitrile, polyacrylic acid, polyacrylic acid methyl ester, polyacrylic acid ethyl ester, poly Acrylate hexyl ester, polymethacrylic acid, polymethacrylic acid methyl ester, polymethacrylic acid ethyl ester, polymethacrylic acid hexyl ester, polyvinyl acetate, polyvinylpyrrolidone, polyether, polycarbonate, polyether sulfone, polyether ketone, polyether Ether ketone, polyphenylene sulfide, hexafluoropolypropylene
- tetrafluoroethylene, hexafluoroethylene, hexafluoropropylene, perfluoroalkyl vinyl ether, vinylidene fluoride, chlorotrifluoroethylene, ethylene, propylene, butadiene, styrene, pentafluoropropylene, fluoromethyl vinyl ether, acrylic acid ester, acrylic acid , and hexadiene may also be used.
- One selected from these may be used alone, or two or more may be used in combination.
- the binder may be an elastomer because it has excellent binding properties. Elastomers are polymers that have rubber elasticity.
- the elastomer used as the binder may be a thermoplastic elastomer or a thermosetting elastomer.
- the binder may contain a thermoplastic elastomer.
- thermoplastic elastomers styrene-ethylene-butylene-styrene (SEBS), styrene-ethylene-propylene-styrene (SEPS), styrene-ethylene-ethylene-propylene-styrene (SEEPS), butylene rubber (BR), isoprene rubber (IR) , chloroprene rubber (CR), acrylonitrile-butadiene rubber (NBR), styrene-butylene rubber (SBR), styrene-butadiene-styrene (SBS), styrene-isoprene-styrene (SIS), hydrogenated isoprene rubber (HIR), hydrogenated Butyl rubber (HIIR), hydrogenated nitrile rubber (HNBR), hydrogenated styrene-butylene rubber (HSBR), polyvinylidene fluoride (PVdF), polytetrafluoroethylene (PTFE) and
- the positive electrode material 10 may contain a conductive aid for the purpose of increasing electronic conductivity.
- conductive aids include graphites such as natural graphite or artificial graphite, carbon blacks such as acetylene black and Ketjen black, conductive fibers such as carbon fiber or metal fiber, carbon fluoride, and metal powder such as aluminum.
- conductive whiskers such as zinc oxide or potassium titanate, conductive metal oxides such as titanium oxide, conductive polymer compounds such as polyaniline, polypyrrole, polythiophene, and the like. Cost reduction can be achieved when a carbon conductive aid is used.
- the positive electrode material 10 is obtained by mixing the positive electrode active material 100, the first solid electrolyte 101 and the second solid electrolyte 102 together.
- a method for mixing the positive electrode active material 100, the first solid electrolyte 101, and the second solid electrolyte 102 is not particularly limited.
- the positive electrode active material 100, the first solid electrolyte 101, and the second solid electrolyte 102 may be mixed using a tool such as a mortar, and the positive electrode active material 100 and the first solid electrolyte 101 are mixed using a mixing device such as a ball mill. It may be mixed with the second solid electrolyte 102 .
- FIG. 2 is a cross-sectional view showing a schematic configuration of a modification of the positive electrode material according to Embodiment 1.
- the positive electrode active material is a coated active material having a coating layer on at least part of the surface. That is, the cathode material 20 has a coating active material 220 , a first solid electrolyte 201 and a second solid electrolyte 202 .
- Coating active material 220 has positive electrode active material 200 and coating layer 203 .
- the coating layer 203 may contain a material with low electronic conductivity such as an oxide material or an oxide solid electrolyte.
- oxide materials include SiO 2 , Al 2 O 3 , TiO 2 , B 2 O 3 , Nb 2 O 5 , WO 3 and ZrO 2 .
- oxide solid electrolytes include Li—Nb—O compounds such as LiNbO 3 , Li—B—O compounds such as LiBO 2 and Li 3 BO 3 , Li—Al—O compounds such as LiAlO 2 , Li 4 SiO 4 and the like.
- the base material may be one selected from these or a mixture of two or more.
- the coating layer 203 may be a solid electrolyte having lithium ion conductivity.
- Coating layer 203 is typically an oxide solid electrolyte having lithium ion conductivity.
- the oxide solid electrolyte has high ionic conductivity and excellent high potential stability. By using an oxide solid electrolyte as the coating layer 203, the charging and discharging efficiency of the battery can be improved.
- the material of the coating layer 203 may be a material containing Nb.
- Coating layer 203 typically includes lithium niobate (LiNbO 3 ). According to such a configuration, it is possible to improve the charging and discharging efficiency of the battery.
- As the oxide solid electrolyte as the material of the coating layer 203 it is also possible to use the materials described above.
- the thickness of the coating layer 203 is, for example, 1 nm or more and 500 nm or less. If the thickness of coating layer 203 is appropriately adjusted, contact between positive electrode active material 200 and second solid electrolyte 202 can be sufficiently suppressed.
- the thickness of the coating layer 203 can be specified by thinning the coated active material 220 by a method such as ion milling and observing the cross section of the coated active material 220 with a transmission electron microscope. An average value of thicknesses measured at a plurality of arbitrary positions (for example, 5 points) can be regarded as the thickness of the coating layer 203 .
- the coated active material 220 can be manufactured by the following method.
- the coating layer 203 is formed on the surface of the positive electrode active material 200 .
- a method for forming the coating layer 203 is not particularly limited. Methods for forming the coating layer 203 include a liquid phase coating method and a vapor phase coating method.
- the precursor solution can be a mixed solution (sol solution) of solvent, lithium alkoxide and niobium alkoxide.
- Lithium alkoxides include lithium ethoxide.
- Niobium alkoxides include niobium ethoxide.
- Solvents are, for example, alcohols such as ethanol. The amounts of lithium alkoxide and niobium alkoxide are adjusted according to the target composition of the coating layer 203 . Water may be added to the precursor solution, if desired.
- the precursor solution may be acidic or alkaline.
- the method of applying the precursor solution to the surface of the positive electrode active material 200 is not particularly limited.
- the precursor solution can be applied to the surface of the cathode active material 200 using a tumbling flow granulation coating apparatus.
- the precursor solution can be sprayed onto the positive electrode active material 200 while rolling and flowing the positive electrode active material 200 to apply the precursor solution to the surface of the positive electrode active material 200 . .
- a precursor film is formed on the surface of the positive electrode active material 200 .
- the positive electrode active material 200 coated with the precursor coating is heat-treated. The heat treatment promotes gelation of the precursor coating and forms the coating layer 203 .
- the vapor phase coating method includes a pulsed laser deposition (PLD) method, a vacuum deposition method, a sputtering method, a thermal chemical vapor deposition (CVD) method, a plasma chemical vapor deposition method, and the like.
- PLD pulsed laser deposition
- CVD thermal chemical vapor deposition
- a plasma chemical vapor deposition method and the like.
- an ion-conducting material as a target is irradiated with a high-energy pulse laser (eg, KrF excimer laser, wavelength: 248 nm) to deposit sublimated ion-conducting material on the surface of the positive electrode active material 100 .
- a high-energy pulse laser eg, KrF excimer laser, wavelength: 248 nm
- high-density sintered LiNbO 3 is used as a target.
- the method of forming the coating layer 203 is not limited to the above.
- the coating layer 203 may be formed by various methods such as a spray method, a spray dry coating method, an electrodeposition method, an immersion method, and a mechanical mixing method using a disperser.
- FIG. 3 is a cross-sectional view showing a schematic configuration of a battery according to Embodiment 2.
- FIG. Battery 300 includes positive electrode 301 , separator layer 302 and negative electrode 303 .
- a separator layer 302 is arranged between the positive electrode 301 and the negative electrode 303 .
- Positive electrode 301 includes at least one of positive electrode material 10 and positive electrode material 20 described in the first embodiment. With such a configuration, the safety of battery 300 can be improved.
- each of the positive electrode 301 and the negative electrode 303 may be 10 ⁇ m or more and 500 ⁇ m or less. When the thickness of the positive electrode 301 and the negative electrode 303 is 10 ⁇ m or more, sufficient energy density of the battery can be ensured. When the thickness of the positive electrode 301 and the negative electrode 303 is 500 ⁇ m or less, the battery 300 can operate at high output.
- the separator layer 302 is a layer containing an electrolyte material. Separator layer 302 may contain at least one solid electrolyte selected from the group consisting of sulfide solid electrolytes, oxide solid electrolytes, halide solid electrolytes, polymer solid electrolytes, and complex hydride solid electrolytes. Details of each solid electrolyte are as described in the first embodiment.
- the thickness of the separator layer 302 may be 1 ⁇ m or more and 300 ⁇ m or less. When the thickness of the separator layer 302 is 1 ⁇ m or more, the positive electrode 301 and the negative electrode 303 can be separated more reliably. When the separator layer 302 has a thickness of 300 ⁇ m or less, the battery 300 can operate at high output.
- the negative electrode 303 contains, as a negative electrode active material, a material that has the property of intercalating and deintercalating metal ions (eg, lithium ions).
- Metal materials, carbon materials, oxides, nitrides, tin compounds, silicon compounds, etc. can be used as negative electrode active materials.
- the metal material may be a single metal.
- the metallic material may be an alloy.
- metal materials include lithium metal and lithium alloys.
- Examples of carbon materials include natural graphite, coke, ungraphitized carbon, carbon fiber, spherical carbon, artificial graphite, and amorphous carbon. From the viewpoint of capacity density, silicon (Si), tin (Sn), silicon compounds, tin compounds, etc. can be preferably used.
- the median diameter of the particles of the negative electrode active material may be 0.1 ⁇ m or more and 100 ⁇ m or less.
- the negative electrode 303 may contain other materials such as a solid electrolyte.
- a solid electrolyte the material described in Embodiment 1 can be used.
- Example 1 [Preparation of coated active material]
- ethoxylithium manufactured by Kojundo Chemical Co., Ltd.
- pentaethoxyniobium manufactured by Kojundo Chemical Co., Ltd.
- NCA Powder of Li(NiCoAl)O 2
- a tumbling fluidization granulation coating apparatus manufactured by Powrex, FD-MP-01E was used for the treatment for forming the coating layer of LiNbO 3 on the surface of the NCA.
- the input amount of NCA, the stirring rotation speed, and the feeding rate of the coating solution were 1 kg, 400 rpm, and 6.59 g/min, respectively.
- the charging amount of the coating solution was adjusted so that the film thickness of LiNbO 3 was 10 nm.
- the input amount of the coating solution was calculated using the specific surface area of the active material and the density of LiNbO 3 .
- Nb-NCA An NCA having a coating layer of LiNbO 3 is hereinafter referred to as "Nb-NCA".
- Nb-NCA solid electrolyte
- LZAF first solid electrolyte
- LPS second solid electrolyte
- the positive electrode active material of Example 1 LZAF and LPS were weighed so that the volume ratio of LZAF:LPS was 6.7:93.3.
- the positive electrode material of Example 1 was produced by mixing these with an agate mortar.
- solid electrolyte means the total volume of LZAF and LPS.
- Example 2 A positive electrode material of Example 2 was obtained in the same manner as in Example 1, except that the volume ratio of LZAF and LPS (ie, LZAF:LPS) was changed to 15:75.
- Example 3 A positive electrode material of Example 3 was obtained in the same manner as in Example 1, except that the volume ratio of LZAF and LPS (ie, LZAF:LPS) was changed to 23.3:76.7.
- Example 4 A positive electrode material of Example 4 was obtained in the same manner as in Example 1, except that the volume ratio of LZAF and LPS (ie, LZAF:LPS) was changed to 33.3:66.7.
- Example 5 A positive electrode material of Example 5 was obtained in the same manner as in Example 1, except that the volume ratio of LZAF and LPS (ie, LZAF:LPS) was changed to 50:50.
- Comparative Example 1 A positive electrode material of Comparative Example 1 was obtained by using only the second solid electrolyte, that is, LPS alone as the solid electrolyte without using LZAF as the first solid electrolyte.
- Table 1 shows the ratio of the LZAF volume to the total volume of LZAF and LPS in the positive electrode materials of Examples and Comparative Examples.
- the cathode material was weighed to contain 14 mg of Nb-NCA.
- LPS and a positive electrode material were laminated in this order in an insulating outer cylinder.
- the resulting laminate was pressure molded at a pressure of 720 MPa.
- metallic lithium was arranged so as to be in contact with the LPS layer, and pressure molding was performed again at a pressure of 40 MPa.
- stainless steel current collectors were arranged above and below the laminate.
- a current collecting lead was attached to each current collector.
- the inside of the outer cylinder was isolated from the outside atmosphere by sealing the outer cylinder with an insulating ferrule. Batteries of Examples 1 to 6 and Comparative Example 1 were produced through the above steps.
- a surface pressure of 150 MPa was applied to the battery by restraining the battery from above and below with four bolts.
- the charged battery was disassembled in an argon glove box, and only the positive electrode material was taken out. 2 mg of cathode material was placed in a stainless steel closed pan. Thermal analysis samples of Examples 1 to 5 and Comparative Example 1 were thus obtained.
- thermal analysis Using the thermal analysis samples of Examples 1 to 5 and Comparative Example 1, thermal analysis was performed under the following conditions.
- a differential scanning calorimeter (TA Instruments Q1000) was used for thermal analysis. The temperature was raised from 0°C to 400°C at 10°C/min. In the thermal analysis curve, the temperature at which the peak rises was regarded as the exothermic start temperature. Table 1 shows the results.
- the ratio V1/Vt of the volume V1 of the first solid electrolyte to the total volume Vt of the first solid electrolyte and the second solid electrolyte is 3% or more and 60% or less.
- the exothermic start temperature was higher than that of the battery of Comparative Example 1. That is, when the positive electrode material contains the first solid electrolyte within the above volume range, the reaction between the oxygen released from the positive electrode active material and the sulfide solid electrolyte is suppressed, thereby improving the safety of the battery. It has been suggested.
- the ratio of the volume of LZAF to the volume of Nb-NCA is desirably 1% or more.
- the upper limit of the ratio of the volume of LZAF to the volume of Nb-NCA is, for example, 15%.
- the technology of the present disclosure is useful, for example, for all-solid lithium secondary batteries.
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Abstract
Description
正極活物質と、
第1固体電解質と、
第2固体電解質と、
を備え、
前記第1固体電解質は、Li、Zr、M、およびXを含み、
Mは、Li以外の金属元素および半金属元素からなる群より選択される少なくとも1つであり、
Xは、F、Cl、Br、およびIからなる群より選択される少なくとも1つであり、
前記第2固体電解質は、前記第1固体電解質と異なる組成を有し、
前記第1固体電解質と前記第2固体電解質との合計体積に対する前記第1固体電解質の体積の比率が3%以上、かつ、60%以下である。
固体電解質を用いた電池は安全であると認識されているが、常にそうであるとは限らない。例えば、正極活物質から酸素が発生することがある。発生した酸素は、固体電解質を酸化させ、電池の温度を上昇させる。その結果、電池の容器が劣化および破損したり、電池の動作不良が起きたりする可能性がある。したがって、固体電解質を用いた電池についても、安全性を更に向上させることが期待されている。
本開示の第1態様に係る正極材料は、
正極活物質と、
第1固体電解質と、
第2固体電解質と、
を備え、
前記第1固体電解質は、Li、Zr、M、およびXを含み、
Mは、Li以外の金属元素および半金属元素からなる群より選択される少なくとも1つであり、
Xは、F、Cl、Br、およびIからなる群より選択される少なくとも1つであり、
前記第2固体電解質は、前記第1固体電解質と異なる組成を有し、
前記第1固体電解質と前記第2固体電解質との合計体積に対する前記第1固体電解質の体積の比率が3%以上、かつ、60%以下である。
LiαZrβMγXδ・・・式(1)
図1は、実施の形態1に係る正極材料の概略構成を示す断面図である。正極材料10は、正極活物質100、第1固体電解質101、および第2固体電解質102を備える。
正極活物質100は、金属イオン(例えば、リチウムイオン)を吸蔵および放出する特性を有する材料を含む。正極活物質100として、リチウム含有遷移金属酸化物、遷移金属フッ化物、ポリアニオン材料、フッ素化ポリアニオン材料、遷移金属硫化物、遷移金属オキシ硫化物、遷移金属オキシ窒化物などが使用されうる。特に、正極活物質100として、リチウム含有遷移金属酸化物を用いた場合には、電池の製造コストを安くでき、平均放電電圧を高めることができる。リチウム含有遷移金属酸化物としては、Li(NiCoAl)O2、Li(NiCoMn)O2、LiCoO2などが挙げられる。
第1固体電解質101は、例えば、イオン伝導性を有する。イオン伝導性は、典型的には、リチウムイオン伝導性である。第1固体電解質101の原料、第1固体電解質101を作製する際に生じる副生成物などは、不可避不純物に含まれる。第1固体電解質101の全体の質量に対する不可避不純物の質量の比率は、5%以下であってもよく、3%以下であってもよく、1%以下であってもよく、0.5%以下であってもよい。
LiαZrβMγXδ・・・式(1)
Li6-(4-x)b(Zr1-xAlx)bF6 ・・・式(2)
第1固体電解質としてのハロゲン化物固体電解質は、例えば下記の方法により製造され得る。
第2固体電解質102は、ハロゲン化物固体電解質、硫化物固体電解質、酸化物固体電解質、高分子固体電解質、および錯体水素化物固体電解質からなる群より選択される少なくとも1つを含んでいてもよい。
正極材料10には、粒子同士の密着性を向上する目的で、結着剤が含まれていてもよい。結着剤は、正極を構成する材料の結着性を向上するために用いられる。結着剤としては、ポリフッ化ビニリデン、ポリテトラフルオロエチレン、ポリエチレン、ポリプロピレン、アラミド樹脂、ポリアミド、ポリイミド、ポリアミドイミド、ポリアクリルニトリル、ポリアクリル酸、ポリアクリル酸メチルエステル、ポリアクリル酸エチルエステル、ポリアクリル酸ヘキシルエステル、ポリメタクリル酸、ポリメタクリル酸メチルエステル、ポリメタクリル酸エチルエステル、ポリメタクリル酸ヘキシルエステル、ポリ酢酸ビニル、ポリビニルピロリドン、ポリエーテル、ポリカーボネート、ポリエーテルサルフォン、ポリエーテルケトン、ポリエーテルエーテルケトン、ポリフェニレンサルファイド、ヘキサフルオロポリプロピレン、スチレンブタジエンゴム、カルボキシメチルセルロース、エチルセルロースなどが挙げられる。また、テトラフルオロエチレン、ヘキサフルオロエチレン、ヘキサフルオロプロピレン、パーフルオロアルキルビニルエーテル、フッ化ビニリデン、クロロトリフルオロエチレン、エチレン、プロピレン、ブタジエン、スチレン、ペンタフルオロプロピレン、フルオロメチルビニルエーテル、アクリル酸エステル、アクリル酸、およびヘキサジエンからなる群より選択される2種以上のモノマーの共重合体も使用されうる。これらから選ばれる1種が単独で使用されてもよく、2種以上が組み合わされて使用されてもよい。
正極材料10は、正極活物質100と第1固体電解質101と第2固体電解質102とを混合することによって得られる。正極活物質100と第1固体電解質101と第2固体電解質102とを混合する方法は特に限定されない。乳鉢などの器具を用いて正極活物質100と第1固体電解質101と第2固体電解質102とを混合してもよく、ボールミルなどの混合装置を用いて正極活物質100と第1固体電解質101と第2固体電解質102とを混合してもよい。
図2は、実施の形態1に係る正極材料の変形例の概略構成を示す断面図である。この変形例においては、正極活物質は、表面の少なくとも一部に被覆層を有する被覆活物質である。すなわち、正極材料20は、被覆活物質220と、第1固体電解質201と、第2固体電解質202とを有する。被覆活物質220は、正極活物質200および被覆層203を有する。
図3は、実施の形態2に係る電池の概略構成を示す断面図である。電池300は、正極301、セパレータ層302、および負極303を含む。セパレータ層302は、正極301と負極303との間に配置されている。正極301は、実施の形態1で説明した正極材料10および正極材料20の少なくとも1つを含む。このような構成によれば、電池300の安全性を向上させることができる。
[被覆活物質の作製]
アルゴングローブボックス内で、5.95gのエトキシリチウム(高純度化学社製)と36.43gのペンタエトキシニオブ(高純度化学社製)とを500mLの超脱水エタノール(和光純薬社製)に溶解して被覆溶液を作製した。
露点-60℃以下のアルゴングローブボックス内で、原料粉末であるLiF、ZrF4、およびAlF3を、LiF:ZrF4:AlF3=2.5:0.5:0.5のモル比で秤量した。これらを乳鉢で粉砕して混合して混合物を得た。得られた混合粉は、遊星型ボールミルを用い、12時間、500rpmでミリング処理された。このようにして、実施例1によるハロゲン化物固体電解質の粉末が得られた。実施例1による第1固体電解質は、Li2.5Zr0.5Al0.5F6(以下、「LZAF」と表記)により表される組成を有していた。
露点-60℃以下のアルゴングローブボックス内で、原料粉末であるLi2SとP2S5とを、モル比でLi2S:P2S5=75:25となるように秤量した。これらを乳鉢で粉砕および混合して混合物を得た。その後、遊星型ボールミル(フリッチュ社製、P-7型)を用い、10時間、510rpmの条件で混合物をミリング処理した。これにより、ガラス状の固体電解質を得た。ガラス状の固体電解質について、不活性雰囲気中、270℃、2時間の条件で熱処理した。これにより、ガラスセラミックス状の固体電解質であるLi2S-P2S5(以下、「LPS」と記載する)を得た。
アルゴングローブボックス内で、Nb-NCAと固体電解質との体積比率(すなわち、Nb-NCA:固体電解質)が70:30、第1固体電解質(すなわち、LZAF)と第2固体電解質(すなわち、LPS)との体積比率(すなわち、LZAF:LPS)が6.7:93.3となるように、実施例1の正極活物質、LZAFおよびLPSを秤量した。これらをメノウ乳鉢で混合することで、実施例1の正極材料を作製した。Nb-NCAと固体電解質との体積比率において、「固体電解質」は、LZAFおよびLPSの合計体積を意味する。
LZAFとLPSとの体積比率(すなわち、LZAF:LPS)を15:75に変更したことを除き、実施例1と同じ方法で実施例2の正極材料を得た。
LZAFとLPSとの体積比率(すなわち、LZAF:LPS)を23.3:76.7に変更したことを除き、実施例1と同じ方法で実施例3の正極材料を得た。
LZAFとLPSの体積比率(すなわち、LZAF:LPS)を33.3:66.7に変更したことを除き、実施例1と同じ方法で実施例4の正極材料を得た。
LZAFとLPSの体積比率(すなわち、LZAF:LPS)を50:50に変更したことを除き、実施例1と同じ方法で実施例5の正極材料を得た。
第1固体電解質であるLZAFを用いず、第2固体電解質のみ、すなわちLPSのみを固体電解質として用いて、比較例1の正極材料を得た。
14mgのNb-NCAが含まれるように正極材料を秤量した。絶縁性を有する外筒の中にLPSと正極材料とをこの順に積層した。得られた積層体を720MPaの圧力で加圧成形した。次に、LPS層に接するように金属リチウムを配置し、再度40MPaの圧力にて加圧成形した。これにより、正極、固体電解質層および負極からなる積層体を作製した。次に、積層体の上下にステンレス鋼製の集電体を配置した。各集電体に集電リードを取り付けた。次に、絶縁性フェルールを用いて外筒を密閉することで外筒の内部を外気雰囲気から遮断した。以上の工程を経て、実施例1から6および比較例1の電池を作製した。4本のボルトで電池を上下から拘束することで、電池に面圧150MPaの圧力を印加した。
電池を25℃の恒温槽に配置した。電池の理論容量に対して0.05Cレート(20時間率)となる電流値147μAで電圧4.3Vに達するまで電池を定電流充電した。電流値2.9μAに到達するまで4.3Vで定電圧充電を行った。
実施例1から5および比較例1の熱分析サンプルを用いて、以下の条件で熱分析を実施した。
表1に示すように、正極材料において、第1固体電解質と第2固体電解質との合計体積Vtに対する第1固体電解質の体積V1の比率V1/Vtが、3%以上、かつ、60%以下の範囲内である実施例1から5の電池では、比較例1の電池に対して発熱開始温度が上昇した。つまり、正極材料が第1固体電解質を上記の体積範囲内で含むことにより、正極活物質から放出される酸素と硫化物固体電解質との反応が抑制され、これにより、電池の安全性が向上することが示唆された。
100,200 正極活物質
101,201 第1固体電解質
102,202 第2固体電解質
203 被覆層
220 被覆活物質
300 電池
301 正極
302 セパレータ層
303 負極
Claims (13)
- 正極活物質と、
第1固体電解質と、
第2固体電解質と、
を備え、
前記第1固体電解質は、Li、Zr、M、およびXを含み、
Mは、Li以外の金属元素および半金属元素からなる群より選択される少なくとも1つであり、
Xは、F、Cl、Br、およびIからなる群より選択される少なくとも1つであり、
前記第2固体電解質は、前記第1固体電解質と異なる組成を有し、
前記第1固体電解質と前記第2固体電解質との合計体積に対する、前記第1固体電解質の体積の比率が、3%以上、かつ、60%以下である、
正極材料。 - 前記第1固体電解質と前記第2固体電解質との合計体積に対する、前記第1固体電解質の体積の比率が、3.3%以上、かつ、50%以下である、
請求項1に記載の正極材料。 - 前記第1固体電解質と前記第2固体電解質との合計体積に対する、前記第1固体電解質の体積の比率が、6.7%以上、かつ、50%以下である、
請求項2に記載の正極材料。 - 前記第1固体電解質と前記第2固体電解質との合計体積に対する、前記第1固体電解質の体積の比率が、33%以上、かつ、50%以下である、
請求項3に記載の正極材料。 - 前記第1固体電解質と前記第2固体電解質との合計体積に対する、前記第1固体電解質の体積の比率が、3.3%以上、かつ、8.0%以下である、
請求項2に記載の正極材料。 - 前記第2固体電解質は、LiおよびSを含む、
請求項1から5のいずれか一項に記載の正極材料。 - Mは、アルミニウムを含む、
請求項1から6のいずれか一項に記載の正極材料。 - 前記第1固体電解質は、下記の組成式(1)により表され、
LiαZrβMγXδ・・・式(1)
ここで、α、β、γ、およびδは、それぞれ独立して、0より大きい値である、
請求項1から7のいずれか1項に記載の正極材料。 - 前記正極活物質は、表面の少なくとも一部に被覆層を有する、
請求項1から8のいずれか1項に記載の正極材料。 - 前記被覆層が、リチウムイオン伝導性を有する酸化物固体電解質を含む、
請求項9に記載の正極材料。 - 前記被覆層が、ニオブ酸リチウムを含む、
請求項9または10に記載の正極材料。 - 請求項1から11のいずれか1項に記載の正極材料を含む、正極。
- 請求項12に記載の正極を備えた、電池。
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| EP22849081.9A EP4379832A4 (en) | 2021-07-29 | 2022-06-23 | POSITIVE ELECTRODE MATERIAL, POSITIVE ELECTRODE AND BATTERY |
| JP2023538338A JP7777807B2 (ja) | 2021-07-29 | 2022-06-23 | 正極材料、正極、および電池 |
| CN202280051225.2A CN117769766A (zh) | 2021-07-29 | 2022-06-23 | 正极材料、正极和电池 |
| US18/418,288 US20240162484A1 (en) | 2021-07-29 | 2024-01-21 | Positive electrode material, positive electrode, and battery |
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| US20220285726A1 (en) * | 2020-03-13 | 2022-09-08 | Maxell, Ltd. | Electrode for all-solid-state battery and all-solid-state battery |
| WO2024262260A1 (ja) * | 2023-06-22 | 2024-12-26 | パナソニックIpマネジメント株式会社 | 正極材料、正極及び電池 |
| WO2024262259A1 (ja) * | 2023-06-22 | 2024-12-26 | パナソニックIpマネジメント株式会社 | 正極材料、正極及び電池 |
| WO2025115822A1 (ja) * | 2023-11-29 | 2025-06-05 | パナソニックIpマネジメント株式会社 | 被覆活物質、正極、及び電池 |
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| WO2023037776A1 (ja) * | 2021-09-13 | 2023-03-16 | パナソニックIpマネジメント株式会社 | 被覆活物質、被覆活物質の製造方法、正極材料、および電池 |
| US20260005227A1 (en) | 2024-06-28 | 2026-01-01 | GM Global Technology Operations LLC | Spray-dry coating of electroactive particles |
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