Classifications

• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M10/00—Secondary cells; Manufacture thereof
  • H01M10/05—Accumulators with non-aqueous electrolyte
  • H01M10/056—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes
  • H01M10/0561—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
• • C—CHEMISTRY; METALLURGY
  • C01—INORGANIC CHEMISTRY
  • C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
  • C01G35/00—Compounds of tantalum
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
  • H01B1/00—Conductors or conductive bodies characterised by the conductive materials; Selection of materials as conductors
  • H01B1/06—Conductors or conductive bodies characterised by the conductive materials; Selection of materials as conductors mainly consisting of other non-metallic substances
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
  • H01B1/00—Conductors or conductive bodies characterised by the conductive materials; Selection of materials as conductors
  • H01B1/06—Conductors or conductive bodies characterised by the conductive materials; Selection of materials as conductors mainly consisting of other non-metallic substances
  • H01B1/08—Conductors or conductive bodies characterised by the conductive materials; Selection of materials as conductors mainly consisting of other non-metallic substances oxides
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
  • H01B13/00—Apparatus or processes specially adapted for manufacturing conductors or cables
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M10/00—Secondary cells; Manufacture thereof
  • H01M10/05—Accumulators with non-aqueous electrolyte
  • H01M10/052—Li-accumulators
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M10/00—Secondary cells; Manufacture thereof
  • H01M10/05—Accumulators with non-aqueous electrolyte
  • H01M10/052—Li-accumulators
  • H01M10/0525—Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M4/00—Electrodes
  • H01M4/02—Electrodes composed of, or comprising, active material
  • H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
• • 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
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M2300/00—Electrolytes
  • H01M2300/0017—Non-aqueous electrolytes
  • H01M2300/0065—Solid electrolytes
  • H01M2300/0068—Solid electrolytes inorganic
  • H01M2300/008—Halides
• • 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 a solid electrolyte material and a battery using the same.
• Patent Document 1 discloses a solid electrolyte material containing Li, M, O, and X.
• M is at least one element selected from the group consisting of Nb and Ta
• X is at least one element selected from the group consisting of Cl, Br, and I.
• An object of the present disclosure is to provide a solid electrolyte material that has practical ionic conductivity and improved contact with other materials.
• the solid electrolyte material of the present disclosure includes: A solid electrolyte material containing Li, M, O, and X,
• M is at least one selected from the group consisting of Nb and Ta
• X is at least one selected from the group consisting of F, Cl, Br, and I
• the solid electrolyte material has a specific surface area greater than 7.5 m 2 /g.
• the present disclosure provides a solid electrolyte material that has practical ionic conductivity and improved contact with other materials.
• FIG. 1 shows a cross-sectional view of a battery 1000 according to a second embodiment.
• FIG. 2 shows a cross-sectional view of an electrode material 1100 according to a second embodiment.
• FIG. 3 shows a schematic diagram of a pressure molding die 300 used to evaluate the ionic conductivity of solid electrolyte materials.
• the solid electrolyte material according to the first aspect of the present disclosure is A solid electrolyte material containing Li, M, O, and X,
• M is at least one selected from the group consisting of Nb and Ta
• X is at least one selected from the group consisting of F, Cl, Br, and I
• the solid electrolyte material has a specific surface area greater than 7.5 m 2 /g.
• the solid electrolyte material according to the first aspect has practical ionic conductivity, a large specific surface area, and good contact with other materials, so it can improve the charging and discharging characteristics of the battery.
• X may include Cl.
• the solid electrolyte material according to the second aspect has improved ionic conductivity.
• M may include Ta.
• the solid electrolyte material according to the third aspect has improved ionic conductivity.
• the molar ratio of Li to M may be 0.60 or more and 3.0 or less. good.
• the solid electrolyte material according to the fourth aspect has improved ionic conductivity.
• the molar ratio of O to X may be 0.05 or more and 0.4 or less.
• the solid electrolyte material according to the fifth aspect has improved ionic conductivity.
• the solid electrolyte material according to any one of the first to fifth aspects may have a specific surface area of 9.8 m 2 /g or more.
• the solid electrolyte material according to the sixth aspect has better contact with other materials.
• the solid electrolyte material according to any one of the first to sixth aspects may have a specific surface area of 20 m 2 /g or less.
• the solid electrolyte material according to the seventh aspect can improve the charging and discharging characteristics of a battery.
• the solid electrolyte material according to any one of the first to seventh aspects may have a specific surface area of 16.4 m 2 /g or less.
• the solid electrolyte material according to the eighth aspect can improve the charging and discharging characteristics of a battery.
• the manufacturing method according to the ninth aspect of the present disclosure includes: A method for producing a solid electrolyte material according to any one of the first to eighth aspects, comprising: The method includes wet-pulverizing a mixture containing a raw material composition containing the constituent components of the solid electrolyte material and a solvent.
• the manufacturing method according to the ninth aspect can manufacture a solid electrolyte material that has practical ionic conductivity and a high specific surface area.
• the solvent may include at least one selected from the group consisting of heptane and parachlorotoluene.
• the manufacturing method according to the tenth aspect can manufacture a solid electrolyte material that has practical ionic conductivity and a high specific surface area.
• the battery according to the eleventh aspect of the present disclosure includes: positive electrode, a negative electrode, and an electrolyte layer disposed between the positive electrode and the negative electrode; Equipped with At least one selected from the group consisting of the positive electrode, the negative electrode, and the electrolyte layer contains the solid electrolyte material according to any one of the first to eighth aspects.
• the battery according to the eleventh aspect has improved charging and discharging characteristics.
• the positive electrode may contain the solid electrolyte material according to any one of the first to eighth aspects.
• the battery according to the twelfth aspect has improved charging and discharging characteristics.
• the solid electrolyte material according to the first embodiment is a solid electrolyte material containing Li, M, O, and X, where M is at least one selected from the group consisting of Nb and Ta, and X is at least one selected from the group consisting of F, Cl, Br, and I.
• the specific surface area of the solid electrolyte material according to the first embodiment is greater than 7.5 m 2 /g.
• the specific surface area of the solid electrolyte material in the present disclosure means the specific surface area determined by the BET method.
• the solid electrolyte material according to the first embodiment is suitable for lithium ion conduction and has good contact with other materials. Therefore, the solid electrolyte material according to the first embodiment can reduce the resistance at the interface with other materials.
• the other material is, for example, an active material.
• Polycrystalline materials are generally used as active materials for lithium ion secondary batteries.
• the surface of an active material is not flat and often has irregularities such as small grooves or depressions.
• the solid electrolyte needs to be deformed by compression or the like to match the uneven shape of the active material.
• the surface of the solid electrolyte is flat and the particle size of the solid electrolyte is large, the pressure during pressing will be concentrated on the convex portions of the active material surface, making it impossible to obtain good contact to the inside of the concave portions.
• the particle size of the solid electrolyte is smaller than the recesses on the surface of the active material, pressure is applied when the solid electrolyte enters the recesses, and good contact properties can be obtained.
• the solid electrolyte surface has irregularities, the solid electrolyte can more easily enter the recesses on the active material surface than when the surface is flat, so good contact between the solid electrolyte and the active material can be improved. It becomes easier to realize.
• the fact that the particle size is small or that the surface is uneven means that the specific surface area is large. In other words, a solid electrolyte with a large specific surface area can easily achieve good contact with the active material. As a result, the resistance of the battery can be reduced, and for example, the charging and discharging characteristics of the battery can be improved.
• the solid electrolyte material according to the first embodiment has practical ionic conductivity, and may have high lithium ion conductivity, for example.
• an example of high lithium ion conductivity is 0.1 mS/cm or more near room temperature.
• the solid electrolyte material according to the first embodiment can have an ionic conductivity of 0.1 mS/cm or more, for example. That is, the solid electrolyte material according to the first embodiment is suitable for lithium ion conduction.
• the solid electrolyte material according to the first embodiment can be used because it has excellent charge and discharge characteristics.
• An example of a battery is a solid state battery.
• the all-solid-state battery may be a primary battery or a secondary battery.
• the solid electrolyte material according to the first embodiment contains substantially no sulfur.
• the solid electrolyte material according to the first embodiment does not substantially contain sulfur, which means that the solid electrolyte material does not contain sulfur as a constituent element, except for sulfur that is unavoidably mixed as an impurity.
• the amount of sulfur mixed as an impurity into the solid electrolyte material is, for example, 1 mol % or less.
• the solid electrolyte material according to the first embodiment does not contain sulfur. Solid electrolyte materials that do not contain sulfur do not generate hydrogen sulfide even when exposed to the atmosphere, so they are highly safe.
• the solid electrolyte material according to the first embodiment may consist essentially of Li, M, O, and X.
• the solid electrolyte material according to the first embodiment substantially consists of Li, M, O, and X
• the total amount of substances of all elements constituting the solid electrolyte material according to the first embodiment This means that the molar ratio of the sum of the amounts of Li, M, O, and X to the total amount of substances is 90% or more. As an example, the molar ratio may be 95% or more.
• the solid electrolyte material according to the first embodiment may consist only of Li, M, O, and X.
• X may contain Cl in order to improve the ionic conductivity of the solid electrolyte material.
• X may be Cl.
• M may include Ta in the solid electrolyte material according to the first embodiment.
• M may be Ta.
• the molar ratio of Li to M (hereinafter referred to as "Li/M molar ratio”) is 0.60 or more and 3. It may be less than .0.
• the molar ratio of O to X (hereinafter referred to as "O/X molar ratio”) may be 0.05 or more and 0.4 or less.
• the Li/M molar ratio may be 0.60 or more and 3.0 or less, and the O/X molar ratio may be 0.05 or more and 0.4 or less.
• the Li/M molar ratio may be 1.3 or more and 1.4 or less in the solid electrolyte material according to the first embodiment.
• the O/X molar ratio may be 0.2 or more and 0.26 or less.
• the Li/M molar ratio is 1.3 or more and 1.4 or less, and the O/X molar ratio is 0.2 or more and 0.26 or less. Good too.
• the specific surface area of the solid electrolyte material according to the first embodiment may be 9.8 m 2 /g or more.
• the specific surface area of the solid electrolyte material according to the first embodiment may be 20 m 2 /g or less.
• the specific surface area may be 16.4 m 2 /g or less.
• the solid electrolyte material When the shape of the solid electrolyte material according to the first embodiment is particulate (for example, spherical), the solid electrolyte material may have a median diameter of 0.1 ⁇ m or more and 100 ⁇ m or less, or 0.5 ⁇ m or less. It may have a median diameter of at least 10 ⁇ m. Thereby, the solid electrolyte material according to the first embodiment and other materials can be well dispersed.
• the median diameter of particles means the particle diameter (d50) corresponding to 50% cumulative volume in a volume-based particle size distribution. Volume-based particle size distribution can be measured by a laser diffraction measurement device or an image analysis device.
• the solid electrolyte material according to the first embodiment has a particulate shape (for example, spherical shape)
• the solid electrolyte material may have a smaller median diameter than the active material. Thereby, the solid electrolyte material and active material according to the first embodiment can form a good dispersed state.
• the solid electrolyte material according to the first embodiment may be manufactured by the following method.
• a plurality of raw material powders weighed to have the desired composition and an organic solvent are mixed while being pulverized in a mixing device.
• raw material powder is prepared so that it has the desired composition.
• raw material powders are oxides, hydroxides, halides, or acid halides.
• the values of the molar ratio Li/M and the molar ratio O/X at the time of mixing raw materials are 1.2 and 0.17, respectively.
• the element types of M and X are determined.
• the mixing ratio of the raw material powders the molar ratios of Li/M and O/X are determined.
• the raw material powders may be mixed in a pre-adjusted molar ratio to offset compositional changes that may occur during the synthesis process.
• the raw material powder and organic solvent are placed in a mixing device such as a planetary ball mill and mixed while being pulverized. That is, processing is performed using a wet ball mill.
• the raw material powder may be mixed before being introduced into the mixing device.
• a slurry with dispersed particles is obtained.
• a solid is obtained by drying the slurry at a temperature depending on the boiling point of the organic solvent used.
• a reactant is obtained by crushing this solid substance in a mortar.
• the particle size of the solid obtained by drying the slurry can be further reduced by dissolving it in an organic solvent and recrystallizing it.
• the raw material powder of the solid electrolyte material may be dissolved in an organic solvent and recrystallized to reduce the particle size, and then processed using a wet ball mill.
• the solid material obtained by drying the slurry may be calcined in vacuum or in an inert atmosphere. Firing is performed, for example, at a temperature of 50° C. or higher and 300° C. or lower for 1 hour or more. In order to suppress compositional changes during firing, firing may be performed in a closed container such as a quartz tube.
• the solid electrolyte material according to the first embodiment is obtained by performing wet pulverization of the mixture containing the raw material composition containing the constituent components of the solid electrolyte material and the solvent.
• the particle size of the balls used in the wet ball mill may be reduced.
• the amount of balls used in the wet ball mill may be increased.
• the processing time using a wet ball mill may be increased.
• the solvent used in the wet ball mill may include at least one selected from the group consisting of heptane and parachlorotoluene.
• the solid electrolyte material obtained by drying the solvent may be annealed.
• the composition of the solid electrolyte material can be determined, for example, by inductively coupled plasma optical emission spectroscopy, ion chromatography, or inert gas melting-infrared absorption.
• the composition of Li and M can be determined by inductively coupled plasma optical emission spectroscopy
• the composition of X can be determined by ion chromatography
• O can be measured by inert gas fusion-infrared absorption.
• the battery according to the second embodiment includes a positive electrode, an electrolyte layer, and a negative electrode.
• An electrolyte layer is disposed between the positive electrode and the negative electrode.
• At least one selected from the group consisting of the positive electrode, the electrolyte layer, and the negative electrode contains the solid electrolyte material according to the first embodiment.
• the battery according to the second embodiment contains the solid electrolyte material according to the first embodiment, it has excellent charge and discharge characteristics.
• FIG. 1 shows a cross-sectional view of a battery 1000 according to the second embodiment.
• the battery 1000 includes a positive electrode 201, an electrolyte layer 202, and a negative electrode 203. Electrolyte layer 202 is arranged between positive electrode 201 and negative electrode 203.
• the positive electrode 201 contains positive electrode active material particles 204 and solid electrolyte particles 100.
• the electrolyte layer 202 contains an electrolyte material.
• the electrolyte material is, for example, a solid electrolyte material.
• the negative electrode 203 contains negative electrode active material particles 205 and solid electrolyte particles 100.
• the solid electrolyte particles 100 are particles containing the solid electrolyte material according to the first embodiment.
• the solid electrolyte particles 100 may be particles containing the solid electrolyte material according to the first embodiment as a main component.
• Particles containing the solid electrolyte material according to the first embodiment as a main component refer to particles in which the component contained in the largest molar ratio is the solid electrolyte material according to the first embodiment.
• the solid electrolyte particles 100 may be particles made of the solid electrolyte material according to the first embodiment.
• the positive electrode 201 contains a material that can insert and release metal ions such as lithium ions.
• the positive electrode 201 contains, for example, a positive electrode active material (for example, positive electrode active material particles 204).
• positive electrode active materials are lithium-containing transition metal oxides, transition metal fluorides, polyanionic materials, fluorinated polyanionic materials, transition metal sulfides, transition metal oxysulfides, or transition metal oxynitrides.
• lithium-containing transition metal oxides are Li(Ni,Co,Al) O2 , Li(Ni,Co,Mn) O2 , or LiCoO2 .
• (A, B, C) means "at least one selected from the group consisting of A, B, and C.”
• lithium phosphate may be used as the positive electrode active material.
• the positive electrode 201 may contain the solid electrolyte material according to the first embodiment.
• lithium iron phosphate may be used as the positive electrode active material.
• the solid electrolyte material according to the first embodiment containing I is easily oxidized.
• the oxidation reaction of the solid electrolyte material is suppressed. That is, formation of an oxide layer having low lithium ion conductivity is suppressed. As a result, the battery has high charge/discharge efficiency.
• the positive electrode 201 may contain not only the solid electrolyte material according to the first embodiment but also a transition metal oxyfluoride as a positive electrode active material. Even when the solid electrolyte material according to the first embodiment is fluorinated with a transition metal fluoride, a resistance layer is hardly formed. As a result, the battery has high charge/discharge efficiency.
• Transition metal oxyfluorides contain oxygen and fluorine.
• the transition metal oxyfluoride may be a compound represented by the composition formula Lip Me q O m F n .
• Me is Mn, Co, Ni, Fe, Al, Cu, V, Nb, Mo, Ti, Cr, Zr, Zn, Na, K, Ca, Mg, Pt, Au, Ag, Ru, W, At least one selected from the group consisting of B, Si, and P, and the formula: 0.5 ⁇ p ⁇ 1.5, 0.5 ⁇ q ⁇ 1.0, 1 ⁇ m ⁇ 2, and 0 ⁇ n ⁇ 1 is satisfied.
• An example of such a transition metal oxyfluoride is Li 1.05 (Ni 0.35 Co 0.35 Mn 0.3 ) 0.95 O 1.9 F 0.1 .
• the positive electrode active material particles 204 may have a median diameter of 0.1 ⁇ m or more and 100 ⁇ m or less. When the positive electrode active material particles 204 have a median diameter of 0.1 ⁇ m or more, the positive electrode active material particles 204 and the solid electrolyte particles 100 can be well dispersed in the positive electrode 201. This improves the charging and discharging characteristics of the battery. When the positive electrode active material particles 204 have a median diameter of 100 ⁇ m or less, the lithium diffusion rate within the positive electrode active material particles 204 is improved. This allows the battery to operate at high output.
• the positive electrode active material particles 204 may have a larger median diameter than the solid electrolyte particles 100. Thereby, in the positive electrode 201, the positive electrode active material particles 204 and the solid electrolyte particles 100 can be well dispersed.
• the ratio of the volume of the positive electrode active material particles 204 to the total volume of the positive electrode active material particles 204 and the volume of the solid electrolyte particles 100 is 0.30 or more and 0. It may be .95 or less.
• FIG. 2 shows a cross-sectional view of an electrode material 1100 according to a second embodiment.
• Electrode material 1100 is included in positive electrode 201, for example.
• a coating layer 216 may be formed on the surface of the electrode active material particles 206. Thereby, an increase in reaction overvoltage of the battery can be suppressed.
• the coating material included in the coating layer 216 are a sulfide solid electrolyte, an oxide solid electrolyte, or a halide solid electrolyte.
• the coating material may be the solid electrolyte material according to the first embodiment, and X may be at least one selected from the group consisting of Cl and Br.
• the solid electrolyte material according to the first embodiment is less likely to be oxidized than the sulfide solid electrolyte. As a result, an increase in reaction overvoltage of the battery can be suppressed.
• the coating material is the solid electrolyte material according to the first embodiment, and X is from the group consisting of Cl and Br. It may be at least one selected.
• the solid electrolyte material according to the first embodiment that does not contain I is less likely to be oxidized than the solid electrolyte material according to the first embodiment that contains I. As a result, the battery has high charge/discharge efficiency.
• the coating material may include an oxide solid electrolyte.
• the oxide solid electrolyte may be lithium niobate, which has excellent stability even at high potentials. As a result, the battery has high charge/discharge efficiency.
• the positive electrode 201 may consist of a first positive electrode layer containing a first positive electrode active material and a second positive electrode layer containing a second positive electrode active material.
• the second positive electrode layer is disposed between the first positive electrode layer and the electrolyte layer 202, the first positive electrode layer and the second positive electrode layer contain the solid electrolyte material according to the first embodiment including I, and A coating layer 216 is formed on the surface of the second positive electrode active material.
• the solid electrolyte material according to the first embodiment included in the electrolyte layer 202 can be prevented from being oxidized by the second positive electrode active material. As a result, the battery has a high charging capacity.
• Examples of the coating material included in the coating layer 216 are a sulfide solid electrolyte, an oxide solid electrolyte, a polymer solid electrolyte, or a halide solid electrolyte. However, when the coating material is a halide solid electrolyte, I is not included as a halogen element.
• the first positive electrode active material may be the same material as the second positive electrode active material, or may be a different material from the second positive electrode active material.
• the positive electrode 201 may have a thickness of 10 ⁇ m or more and 500 ⁇ m or less.
• the electrolyte layer 202 contains an electrolyte material.
• the electrolyte material is, for example, a solid electrolyte material.
• Electrolyte layer 202 may be a solid electrolyte layer.
• Electrolyte layer 202 may contain a solid electrolyte material according to the first embodiment.
• the electrolyte layer 202 may be made only of the solid electrolyte material according to the first embodiment.
• the electrolyte layer 202 may be made only of a solid electrolyte material different from the solid electrolyte material according to the first embodiment.
• solid electrolyte materials different from the solid electrolyte material according to the first embodiment include Li 2 MgX' 4 , Li 2 FeX' 4 , Li (Al, Ga, In) X' 4 , Li 3 (Al, Ga, In) )X' 6 or LiI.
• X' is at least one selected from the group consisting of F, Cl, Br, and I.
• the solid electrolyte material according to the first embodiment will be referred to as a first solid electrolyte material.
• a solid electrolyte material different from the solid electrolyte material according to the first embodiment is referred to as a second solid electrolyte material.
• the electrolyte layer 202 may contain not only the first solid electrolyte material but also the second solid electrolyte material.
• the first solid electrolyte material and the second solid electrolyte material may be uniformly dispersed.
• a layer made of the first solid electrolyte material and a layer made of the second solid electrolyte material may be stacked along the stacking direction of the battery 1000.
• the electrolyte layer 202 may have a thickness of 1 ⁇ m or more and 100 ⁇ m or less. When the electrolyte layer 202 has a thickness of 1 ⁇ m or more, the positive electrode 201 and the negative electrode 203 are less likely to be short-circuited. When the electrolyte layer 202 has a thickness of 100 ⁇ m or less, the battery can operate at high power.
• Another electrolyte layer may be further provided between the electrolyte layer 202 and the negative electrode 203.
• the electrolyte layer 202 includes a first solid electrolyte material
• a material that is electrochemically more stable than the first solid electrolyte material is used.
• An electrolyte layer made of another solid electrolyte material may be further provided between electrolyte layer 202 and negative electrode 203.
• the negative electrode 203 contains a material that can insert and release metal ions (for example, lithium ions).
• the negative electrode 203 contains, for example, a negative electrode active material (for example, negative electrode active material particles 205).
• Examples of negative electrode active materials are metal materials, carbon materials, oxides, nitrides, tin compounds, or silicon compounds.
• the metal material may be a single metal or an alloy.
• An example of a metallic material is lithium metal or a lithium alloy.
• Examples of carbon materials are natural graphite, coke, semi-graphitized carbon, carbon fiber, spherical carbon, artificial graphite, or amorphous carbon. From the viewpoint of capacity density, suitable examples of the negative electrode active material are silicon (i.e., Si), tin (i.e., Sn), a silicon compound, or a tin compound.
• the negative electrode active material may be selected based on the reduction resistance of the solid electrolyte material included in the negative electrode 203.
• a material capable of intercalating and deintercalating lithium ions at 0.27 V or higher relative to lithium may be used as the negative electrode active material. If the negative electrode active material is such a material, reduction of the first solid electrolyte material contained in the negative electrode 203 can be suppressed. As a result, the battery has high charge/discharge efficiency.
• examples of such materials are titanium oxide, indium metal or lithium alloys.
• titanium oxides are Li 4 Ti 5 O 12 , LiTi 2 O 4 or TiO 2 .
• the negative electrode active material particles 205 may have a median diameter of 0.1 ⁇ m or more and 100 ⁇ m or less. When the negative electrode active material particles 205 have a median diameter of 0.1 ⁇ m or more, the negative electrode active material particles 205 and the solid electrolyte particles 100 can be well dispersed in the negative electrode 203. This improves the charging and discharging characteristics of the battery. When the negative electrode active material particles 205 have a median diameter of 100 ⁇ m or less, the lithium diffusion rate within the negative electrode active material particles 205 is improved. This allows the battery to operate at high output.
• the negative electrode active material particles 205 may have a larger median diameter than the solid electrolyte particles 100. Thereby, in the negative electrode 203, the negative electrode active material particles 205 and the solid electrolyte particles 100 can be well dispersed.
• the ratio of the volume of the negative electrode active material particles 205 to the sum of the volume of the negative electrode active material particles 205 and the volume of the solid electrolyte particles 100 is 0.30 or more and 0. It may be .95 or less.
• the electrode material 1100 shown in FIG. 2 may be contained in the negative electrode 203.
• a coating layer 216 may be formed on the surface of the electrode active material particles 206.
• the battery has high charge/discharge efficiency.
• the coating material included in the coating layer 216 are a sulfide solid electrolyte, an oxide solid electrolyte, a polymer solid electrolyte, or a halide solid electrolyte.
• the coating material may be a sulfide solid electrolyte, an oxide solid electrolyte, or a polymer solid electrolyte.
• a sulfide solid electrolyte is Li 2 SP 2 S 5 .
• An example of an oxide solid electrolyte is trilithium phosphate.
• An example of a polymeric solid electrolyte is a composite compound of polyethylene oxide and lithium salt. An example of such a polymeric solid electrolyte is lithium bis(trifluoromethanesulfonyl)imide.
• the negative electrode 203 may have a thickness of 10 ⁇ m or more and 500 ⁇ m or less.
• At least one selected from the group consisting of the positive electrode 201, the electrolyte layer 202, and the negative electrode 203 may contain a second solid electrolyte material for the purpose of increasing ionic conductivity.
• the second solid electrolyte material are a sulfide solid electrolyte, an oxide solid electrolyte, a halide solid electrolyte, or an organic polymer solid electrolyte.
• sulfide solid electrolyte means a solid electrolyte containing sulfur.
• Oxide solid electrolyte means a solid electrolyte containing oxygen.
• the oxide solid electrolyte may contain anions other than oxygen (excluding sulfur anions and halogen anions).
• Oxide solid electrolyte means a solid electrolyte that contains a halogen element and does not contain sulfur.
• the halide solid electrolyte may contain not only a halogen element but also oxygen.
• Examples of sulfide solid electrolytes are Li 2 SP 2 S 5 , Li 2 S-SiS 2 , Li 2 SB 2 S 3 , Li 2 S-GeS 2 , Li 3.25 Ge 0.25 P 0.75 S 4 , or It is Li 10 GeP 2 S 12 .
• an oxide solid electrolyte is (i) NASICON type solid electrolyte such as LiTi 2 (PO 4 ) 3 or its elemental substitution product; (ii) a perovskite solid electrolyte such as (LaLi) TiO3 ; (iii) LISICON-type solid electrolytes such as Li 14 ZnGe 4 O 16 , Li 4 SiO 4 , LiGeO 4 or elemental substitutes thereof; (iv) a garnet-type solid electrolyte such as Li 7 La 3 Zr 2 O 12 or its elemental substitution product; or (v) Li 3 PO 4 or its N-substituted product.
• NASICON type solid electrolyte such as LiTi 2 (PO 4 ) 3 or its elemental substitution product
• a perovskite solid electrolyte such as (LaLi) TiO3 ;
• LISICON-type solid electrolytes such as Li 14 ZnGe 4 O 16 , Li 4 SiO 4 , Li
• halide solid electrolyte is a compound represented by Li a Me' b Y c Z 6 .
• Me' is at least one selected from the group consisting of metal elements and metalloid elements other than Li and Y.
• Z is at least one selected from the group consisting of F, Cl, Br, and I.
• the value of m represents the valence of Me'.
• Metalloid elements are B, Si, Ge, As, Sb, and Te.
• Metallic elements include all elements contained in Groups 1 to 12 of the periodic table (excluding hydrogen), and all elements contained in groups 13 to 16 of the periodic table (however, B, Si, Ge, As, Sb, Te, C, N, P, O, S, and Se).
• Me' is selected from the group consisting of Mg, Ca, Sr, Ba, Zn, Sc, Al, Ga, Bi, Zr, Hf, Ti, Sn, Ta, and Nb. It may be at least one selected from the following.
• halide solid electrolytes are Li 3 YCl 6 or Li 3 YBr 6 .
• the negative electrode 203 may contain a sulfide solid electrolyte.
• the sulfide solid electrolyte which is electrochemically stable with respect to the negative electrode active material, prevents the first solid electrolyte material and the negative electrode active material from coming into contact with each other.
• the battery has a low internal resistance.
• organic polymer solid electrolytes examples include polymer compounds and lithium salt compounds.
• the polymer compound may have an ethylene oxide structure. Since a polymer compound having an ethylene oxide structure can contain a large amount of lithium salt, it has higher ionic conductivity.
• lithium salts are LiPF6 , LiBF4 , LiSbF6, LiAsF6 , LiSO3CF3 , LiN ( SO2CF3 ) 2 , LiN( SO2C2F5 ) 2 , LiN( SO2CF3 ) . (SO 2 C 4 F 9 ), or LiC(SO 2 CF 3 ) 3 .
• One type of lithium salt selected from these may be used alone. Alternatively, a mixture of two or more lithium salts selected from these may be used.
• At least one selected from the group consisting of the positive electrode 201, the electrolyte layer 202, and the negative electrode 203 is made of a non-aqueous electrolyte, a gel electrolyte, or a non-aqueous electrolyte for the purpose of facilitating transfer of lithium ions and improving the output characteristics of the battery. It may contain liquid.
• the non-aqueous electrolyte includes a non-aqueous solvent and a lithium salt dissolved in the non-aqueous solvent.
• nonaqueous solvents are cyclic carbonate solvents, chain carbonate solvents, cyclic ether solvents, chain ether solvents, cyclic ester solvents, chain ester solvents, or fluorine solvents.
• cyclic carbonate solvents are ethylene carbonate, propylene carbonate, or butylene carbonate.
• linear carbonate solvents are dimethyl carbonate, ethylmethyl carbonate, or diethyl carbonate.
• cyclic ether solvents are tetrahydrofuran, 1,4-dioxane, or 1,3-dioxolane.
• An example of a linear ether solvent is 1,2-dimethoxyethane or 1,2-diethoxyethane.
• An example of a cyclic ester solvent is ⁇ -butyrolactone.
• An example of a linear ester solvent is methyl acetate.
• fluorine solvents are fluoroethylene carbonate, methyl fluoropropionate, fluorobenzene, fluoroethylmethyl carbonate, or fluorodimethylene carbonate.
• One type of nonaqueous solvent selected from these may be used alone. Alternatively, a mixture of two or more nonaqueous solvents selected from these may be used.
• lithium salts are LiPF6 , LiBF4 , LiSbF6, LiAsF6 , LiSO3CF3 , LiN ( SO2CF3 ) 2 , LiN( SO2C2F5 ) 2 , LiN( SO2CF3 ) . (SO 2 C 4 F 9 ), or LiC(SO 2 CF 3 ) 3 .
• One type of lithium salt selected from these may be used alone. Alternatively, a mixture of two or more lithium salts selected from these may be used.
• the concentration of the lithium salt is, for example, in a range of 0.5 mol/liter or more and 2 mol/liter or less.
• a polymer material impregnated with a non-aqueous electrolyte may be used as the gel electrolyte.
• examples of polymeric materials are polyethylene oxide, polyacrylonitrile, polyvinylidene fluoride, polymethyl methacrylate, or polymers with ethylene oxide linkages.
• ionic liquids examples include: (i) aliphatic chain quaternary salts such as tetraalkylammonium or tetraalkylphosphonium; (ii) aliphatic cyclic ammoniums such as pyrrolidiniums, morpholiniums, imidazoliniums, tetrahydropyrimidiniums, piperaziniums, or piperidiniums; or (iii) nitrogen-containing heteros such as pyridiniums or imidazoliums. ring aromatic cation, It is.
• Examples of anions contained in ionic liquids are PF 6 - , BF 4 - , SbF 6 - , AsF 6 - , SO 3 CF 3 - , N(SO 2 CF 3 ) 2 - , N(SO 2 C 2 F 5 ) 2- , N( SO2CF3 ) ( SO2C4F9 )- , or C ( SO2CF3 ) 3- .
• the ionic liquid may contain a lithium salt.
• At least one selected from the positive electrode 201, the electrolyte layer 202, and the negative electrode 203 may contain a binder for the purpose of improving adhesion between particles.
• binders include polyvinylidene fluoride, polytetrafluoroethylene, polyethylene, polypropylene, aramid resin, polyamide, polyimide, polyamideimide, polyacrylonitrile, polyacrylic acid, polyacrylic acid methyl ester, polyacrylic acid ethyl ester, Polyacrylic acid hexyl ester, polymethacrylic acid, polymethacrylic acid methyl ester, polymethacrylic acid ethyl ester, polymethacrylic acid hexyl ester, polyvinyl acetate, polyvinylpyrrolidone, polyether, polyether sulfone, hexafluoropolypropylene, styrene butadiene rubber , or carboxymethylcellulose.
• Copolymers may be used as binders.
• binders are tetrafluoroethylene, hexafluoroethylene, hexafluoropropylene, perfluoroalkyl vinyl ether, vinylidene fluoride, chlorotrifluoroethylene, ethylene, propylene, pentafluoropropylene, fluoromethyl vinyl ether, acrylic acid, and It is a copolymer of two or more materials selected from the group consisting of hexadiene. Mixtures of two or more selected from the above materials may also be used.
• At least one selected from the positive electrode 201 and the negative electrode 203 may contain a conductive additive for the purpose of increasing electronic conductivity.
• Examples of conductive aids are: (i) graphites such as natural graphite or artificial graphite; (ii) carbon blacks such as acetylene black or Ketjen black; (iii) conductive fibers such as carbon fibers or metal fibers; (iv) fluorinated carbon; (v) metal powders such as aluminum; (vi) conductive whiskers such as zinc oxide or potassium titanate; (vii) a conductive metal oxide such as titanium oxide, or (viii) a conductive polymer compound such as polyaniline, polypyrrole, or polythiophene.
• the above-mentioned conductive aid (i) or (ii) may be used.
• Examples of the shape of the battery according to the second embodiment are a coin shape, a cylindrical shape, a square shape, a sheet shape, a button shape, a flat shape, and a laminated shape.
• a material for forming a positive electrode, a material for forming an electrolyte layer, and a material for forming a negative electrode are prepared, and the positive electrode, the electrolyte layer, and the negative electrode are arranged in this order by a known method. It may also be manufactured by producing a laminate.
• Example 1 Preparation of solid electrolyte material
• dry argon atmosphere having a dew point of -60°C or lower
• a mixture (1 g) of these raw material powders was placed in a pod for a 45 cc planetary ball mill together with a 0.5 mm diameter ball (25 g).
• Heptane (16 g) was added dropwise to the pod as an organic solvent.
• Milling was performed using a planetary ball mill at 600 rpm for 12 hours. After the milling process, the balls were separated to obtain a slurry.
• the obtained slurry was dried at 50° C. for 1 hour under a nitrogen flow using a mantle heater.
• the solid electrolyte material powder according to Example 1 was obtained by pulverizing the obtained solid material in a mortar.
• composition analysis of solid electrolyte material The Li and M contents of the solid electrolyte material were measured by high frequency inductively coupled plasma emission spectrometry using a high frequency inductively coupled plasma emission spectrometer (manufactured by ThermoFisher Scientific, iCAP7400).
• the Cl content was measured by an ion chromatography method using an ion chromatography device (manufactured by Dionex, ICS-2000).
• the O content was measured by inert gas melting-infrared absorption method using an oxygen analyzer (manufactured by Horiba, EMGA-930). From the measurement results, the molar ratios of Li/M and O/X were calculated.
• the Li/M molar ratio of the solid electrolyte material according to Example 1 was 1.3, and the O/X molar ratio was 0.20.
• FIG. 3 shows a schematic diagram of a pressure molding die 300 used to evaluate the ionic conductivity of a solid electrolyte material.
• the pressure molding die 300 included a punch upper part 301, a frame mold 302, and a punch lower part 303.
• the frame mold 302 was made of insulating polycarbonate.
• Both the punch upper part 301 and the punch lower part 303 were made of electronically conductive stainless steel.
• the ionic conductivity of the solid electrolyte material according to Example 1 was measured by the following method.
• the solid electrolyte material powder according to Example 1 (that is, the solid electrolyte material powder 101 in FIG. 3) was filled into the pressure molding die 300. Inside the pressure molding die 300, a pressure of 300 MPa was applied to the solid electrolyte material according to Example 1 using the punch upper part 301.
• the punch upper part 301 and the punch lower part 303 were connected to a potentiostat (Versa STAT 4, manufactured by Princeton Applied Research) equipped with a frequency response analyzer.
• the punch upper part 301 was connected to a working electrode and a terminal for potential measurement.
• Punch lower part 303 was connected to a counter electrode and a reference electrode.
• the ionic conductivity of the solid electrolyte material according to Example 1 was measured at room temperature by electrochemical impedance measurement. As a result, the ionic conductivity measured at 22°C was 0.12 mS/cm.
• BET specific surface area A specific surface area/pore distribution measuring device (BELSORP MINI X, manufactured by Microtrack Bell Co., Ltd.) was used to measure the specific surface area.
• BET specific surface area the specific surface area obtained using this apparatus.
• the powder of the solid electrolyte material according to Example 1 (approximately 1 g) was placed in a dedicated test tube.
• vacuum drying was performed at 80°C for 1 hour.
• the loaded mass was measured from the difference between the weight of the test tube containing the sample after pretreatment and the weight of the test tube before loading the sample.
• the specific surface area of the solid electrolyte material according to Example 1 was 16.4 m 2 /g.
• Example 2 [Preparation of solid electrolyte material]
• a solid electrolyte material according to Example 2 was obtained in the same manner as in Example 1, except that the solid material obtained after solvent drying was post-annealed at 150° C. for 60 minutes.
• Example 3 a solid electrolyte material according to Example 3 was obtained in the same manner as in Example 1, except that parachlorotoluene was used as the organic solvent and the solvent was dried at 170°C.
• Example 4 a solid electrolyte material according to Example 4 was obtained in the same manner as in Example 3, except that the solid material obtained after solvent drying was post-annealed at 200 ° C. for 60 minutes.
• composition analysis of solid electrolyte material In the same manner as in Example 1, composition analysis of the solid electrolyte materials according to Examples 2 to 4 was carried out. The Li/M and O/X molar ratios of the solid electrolyte materials according to Examples 2 to 4 are shown in Table 1.
• the solid electrolyte material according to Reference Example 1 was produced by a dry ball mill without using an organic solvent.
• composition analysis of solid electrolyte material In the same manner as in Example 1, compositional analysis of the solid electrolyte material according to Reference Example 1 was carried out. The molar ratios of Li/M and O/X of the solid electrolyte material according to Reference Example 1 are shown in Table 1.
• the solid electrolyte material according to Reference Example 2 was obtained by firing a mixture of raw materials.
• composition analysis of solid electrolyte material In the same manner as in Example 1, compositional analysis of the solid electrolyte material according to Reference Example 2 was carried out. The molar ratios of Li/M and O/X of the solid electrolyte material according to Reference Example 2 are shown in Table 1.
• the solid electrolyte materials according to Examples 1 to 4 have an ionic conductivity of 0.1 mS/cm or more and a specific surface area of more than 7.5 m 2 /g at room temperature.
• the specific surface area of the solid electrolyte material according to Reference Example 1 produced by dry ball milling and the solid electrolyte material according to Reference Example 2 produced by firing were both 7.5 m 2 /g or less.
• Both Ta and Nb are Group 5 transition metal elements. Therefore, even if part or all of Ta is replaced with Nb, it can have practical ionic conductivity and a high specific surface area. Similarly, even if part or all of the halogen element Cl is replaced with at least one selected from the group consisting of F, Br, and I, it will still have practical ionic conductivity and a high specific surface area. may have.
• the solid electrolyte material according to the present disclosure has practical ionic conductivity and a high specific surface area, so it can realize good contact with the active material. Therefore, the solid electrolyte material according to the present disclosure is suitable for providing a battery with excellent charge and discharge characteristics.
• the solid electrolyte material of the present disclosure is used, for example, in an all-solid lithium ion secondary battery.
• Solid electrolyte particles 101 Powder of solid electrolyte material 201 Positive electrode 202 Electrolyte layer 203 Negative electrode 204 Positive electrode active material particles 205 Negative electrode active material particles 206 Electrode active material particles 216 Covering layer 300 Pressure molding die 301 Punch upper part 302 Frame 303 Punch lower part 1000 Battery 1100 Electrode material

Landscapes

• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Electrochemistry (AREA)
• General Chemical & Material Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Manufacturing & Machinery (AREA)
• Materials Engineering (AREA)
• Inorganic Chemistry (AREA)
• Physics & Mathematics (AREA)
• Condensed Matter Physics & Semiconductors (AREA)
• General Physics & Mathematics (AREA)
• Organic Chemistry (AREA)
• Secondary Cells (AREA)

Priority Applications (2)

Applications Claiming Priority (2)

Related Child Applications (1)

Publications (1)

Family

ID=88242903

Family Applications (1)

Country Status (3)

Families Citing this family (1)

Citations (3)

• 2023
  • 2023-02-28 JP JP2024514184A patent/JPWO2023195271A1/ja active Pending
  • 2023-02-28 WO PCT/JP2023/007417 patent/WO2023195271A1/ja not_active Ceased
• 2024
  • 2024-09-28 US US18/900,635 patent/US20250023095A1/en active Pending

Patent Citations (3)

Also Published As

Similar Documents

Legal Events