WO2013065787A1 - ナトリウム二次電池用負極材料及びその製造方法、並びにナトリウム二次電池用負極及びナトリウム二次電池 - Google Patents
ナトリウム二次電池用負極材料及びその製造方法、並びにナトリウム二次電池用負極及びナトリウム二次電池 Download PDFInfo
- Publication number
- WO2013065787A1 WO2013065787A1 PCT/JP2012/078329 JP2012078329W WO2013065787A1 WO 2013065787 A1 WO2013065787 A1 WO 2013065787A1 JP 2012078329 W JP2012078329 W JP 2012078329W WO 2013065787 A1 WO2013065787 A1 WO 2013065787A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- component
- negative electrode
- secondary battery
- sodium secondary
- electrode material
- Prior art date
Links
Images
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/36—Selection of substances as active materials, active masses, active liquids
- H01M4/362—Composites
- H01M4/366—Composites as layered products
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/36—Selection of substances as active materials, active masses, active liquids
- H01M4/58—Selection of substances as active materials, active masses, active liquids of inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy; of polyanionic structures, e.g. phosphates, silicates or borates
-
- 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
- H01M10/054—Accumulators with insertion or intercalation of metals other than lithium, e.g. with magnesium or aluminium
-
- 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
- H01M10/0564—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes the electrolyte being constituted of organic materials only
- H01M10/0566—Liquid materials
- H01M10/0568—Liquid materials characterised by the solutes
-
- 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
- H01M10/0564—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes the electrolyte being constituted of organic materials only
- H01M10/0566—Liquid materials
- H01M10/0569—Liquid materials characterised by the solvents
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
- H01M4/136—Electrodes based on inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
- H01M4/139—Processes of manufacture
- H01M4/1397—Processes of manufacture of electrodes based on inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/36—Selection of substances as active materials, active masses, active liquids
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/36—Selection of substances as active materials, active masses, active liquids
- H01M4/38—Selection of substances as active materials, active masses, active liquids of elements or alloys
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/36—Selection of substances as active materials, active masses, active liquids
- H01M4/58—Selection of substances as active materials, active masses, active liquids of inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy; of polyanionic structures, e.g. phosphates, silicates or borates
- H01M4/581—Chalcogenides or intercalation compounds thereof
- H01M4/5815—Sulfides
-
- 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
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
- H01M4/621—Binders
- H01M4/622—Binders being polymers
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
- H01M4/624—Electric conductive fillers
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M2004/026—Electrodes composed of, or comprising, active material characterised by the polarity
- H01M2004/027—Negative electrodes
-
- 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
- H01M2300/0025—Organic electrolyte
- H01M2300/0028—Organic electrolyte characterised by the solvent
-
- 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
- H01M2300/0025—Organic electrolyte
- H01M2300/0028—Organic electrolyte characterised by the solvent
- H01M2300/0037—Mixture of solvents
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/10—Energy storage using batteries
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
- Y02P70/50—Manufacturing or production processes characterised by the final manufactured product
Definitions
- the present invention relates to a negative electrode material for a sodium secondary battery and a method for producing the same, and a negative electrode for a sodium secondary battery and a sodium secondary battery.
- Lithium secondary batteries such as lithium ion batteries and lithium polymer batteries have a higher voltage and a higher capacity and are lighter than nickel cadmium batteries and nickel metal hydride batteries. Therefore, in recent years, the use as a main power source for mobile communication devices, portable electronic devices, electric bicycles, electric motorcycles, electric vehicles and the like has been expanded.
- current lithium ion batteries generally use lithium-containing transition metal composite oxides such as lithium cobaltate (LiCoO 2 ), lithium nickelate (LiNiO 2 ), and lithium iron phosphate (LiFePO 4 ) as the positive electrode.
- LiCoO 2 lithium cobaltate
- LiNiO 2 lithium nickelate
- LiFePO 4 lithium iron phosphate
- graphite, hard carbon or the like capable of inserting and extracting lithium is used.
- electrolytes used for lithium ion batteries are mainly cyclic carbonates such as propylene carbonate (PC) and ethylene carbonate (EC), dimethyl carbonate (DMC), diethyl carbonate (DEC), and methyl ethyl carbonate (MEC).
- PC propylene carbonate
- EC ethylene carbonate
- DMC dimethyl carbonate
- DEC diethyl carbonate
- MEC methyl ethyl carbonate
- Lithium tetrafluoroborate LiBF 4 ), lithium hexafluorophosphate (LiPF 6 ), lithium hexafluoroarsenate (LiAsF 6 ), lithium perchlorate (LiClO 4) ), Lithium bistrifluoromethanesulfonylamide (LiN (CF 3 SO 2 ) 2 ), lithium trifluoromethanesulfonate (LiCF 3 SO 3 ), and other electrolyte salts are used.
- a lithium ion battery is an intercalation in which lithium ions move between lithium-containing transition metal oxides such as graphite as a negative electrode active material and LiCoO 2 as a positive electrode active material, and move between molecules of each material. Charging / discharging is performed by causing a phenomenon.
- Graphite has a layered molecular structure, and the structure of graphite is rarely destroyed even when lithium ions enter and exit between the layers. Theoretically, 372 mAh / g of lithium ions can be occluded.
- sodium ions have a large ionic radius and cannot enter between graphite layers, they do not exhibit capacity.
- Patent Document 1 discloses an invention of a secondary battery using an alkali metal as a negative electrode material. Specifically, it is described that lithium metal is used as the alkali metal.
- lithium metal is used as the alkali metal.
- sodium metal (Na) is used as the negative electrode material as the alkali metal, it is theoretically expected that a high capacity can be obtained. Is done.
- sodium metal (Na) is used as the negative electrode material, there is a great disadvantage that dendrites are deposited on the negative electrode during charging and reach the positive electrode side by repeating charging and discharging, causing an internal short circuit phenomenon.
- the deposited dendrites have high reaction activity due to their large specific surface area, and an interfacial film consisting of a decomposition product of a solvent having no electron conductivity is formed on the surface, thereby increasing the internal resistance of the battery. Reduces charge / discharge efficiency. For these reasons, sodium ion batteries using sodium metal have the disadvantages of low reliability and short cycle life.
- Patent Document 2 describes an invention relating to a sodium ion secondary battery using a fibrous carbon material having a diameter of 0.1 ⁇ m to 1.0 ⁇ m as a negative electrode.
- the cycle life is good, but there is a problem that the energy density is small.
- Patent Document 3 describes that in a sodium ion secondary battery, the solvent of the electrolytic solution used for the hard carbon negative electrode is preferably propylene carbonate or a mixed solvent of propylene carbonate and ethylene carbonate.
- the solvent of the electrolytic solution used for the hard carbon negative electrode is preferably propylene carbonate or a mixed solvent of propylene carbonate and ethylene carbonate.
- Non-Patent Document 1 shows that in an EC: DMC system generally used in a lithium ion battery, a hard carbon electrode of a sodium cell has failed to obtain good cycle characteristics. However, it has been reported that better cycle characteristics can be obtained than EC: DMC and PC: DMC systems. That is, Patent Document 3 and Non-Patent Document 1 show that the cycle characteristics of the negative electrode greatly depend on the electrolytic solution.
- Patent Document 4 discloses an example in which sodium ions are contained in a nonaqueous electrolyte in a nonaqueous electrolyte secondary battery using a negative electrode containing Sn alone or Ge alone.
- Patent Document 3 and Non-Patent Document 1 merely examine the case where hard carbon is used as the negative electrode, and do not discuss the electrolyte solution in the alloy-based negative electrode.
- the negative electrode containing Sn alone or Ge described in Patent Document 4 large volume expansion / contraction occurs due to sodium occlusion / release occurring during charging / discharging. As a result, there is a problem that the electrode itself may be broken and the cycle life is poor. Moreover, examination of electrolyte solution is not made
- JP 58-73968 A Japanese Patent Laid-Open No. 3-155062 WO2010 / 109889A1 JP 2006-244976 A
- the present invention has been made in view of the current state of the prior art, and its main object is a negative electrode material for sodium secondary batteries capable of exhibiting excellent cycle characteristics while maintaining a high discharge capacity, and a method for producing the same. And a negative electrode for sodium secondary battery and a sodium secondary battery.
- the negative electrode material for sodium secondary batteries of the present invention is composed of a sulfide or sulfide composite containing sulfur and antimony. Furthermore, it contains the following component (i) as necessary: (I) at least one element selected from the group consisting of Sn, As, Bi, Ge, Ga, Pb, and C; When component (i) is included, the proportions of the above components are sulfur: 10 to 70 mol%, antimony: 10 to 70 mol%, and (i): 3 to 60 mol%.
- the “composite” refers to what is composed of particles to which each component is bonded, and is a different concept from “mixture” in which the particles of each component are simply assembled. .
- the sulfide composite is a solid solution of sulfide such as sulfide glass, crystalline sulfide, sulfide amorphous, etc., and a sulfide coating (the sulfide covers a part or all of the non-sulfide. And a fired body of sulfide.
- the negative electrode material for a sodium secondary battery of the present invention can function as a negative electrode active material having a high capacity and a good cycle life.
- the sulfide composite preferably contains 0.5 to 40 mol% of a Ge component. Since Ge has a role of forming a glass skeleton structure, a vitrified negative electrode material can be obtained. By vitrification, it has water resistance and acid resistance, does not easily react with water or oxygen, does not cause a decrease in ion conductivity, and is easy to handle. Furthermore, a water-based binder can be used, and each manufacturing process does not need to be in a dry atmosphere, so that manufacturing costs can be reduced. That is, it is preferable to vitrify.
- the negative electrode material for a sodium secondary battery of the present invention may be a composite powder of the following A component and B component.
- a material in which component A can electrochemically occlude and release sodium (2) B component is the sulfide or sulfide composite,
- “composite powder” is a different concept from “mixed powder”, and mixed powder is simply a collection of component A powder and component B powder, whereas composite powder is one of the constituents of the powder.
- Both A component and B component are contained in the particles.
- the composite powder is one in which the A component and the B component are bonded (integrated).
- the A component is coated with or supported by the B component (or vice versa). Is included.
- the composite powder is preferably a composite powder in which the B component is coated on the surface of the A component.
- the presence of the B component around the A component as a nucleus (surface) makes it possible to improve the ionic conductivity of the A component associated with occlusion / release (charging / discharging) of sodium. Moreover, the crack resulting from expansion and contraction can be suppressed. As a result, only the A component can improve the ionic conductivity and cycle characteristics even with an active material having poor ion conductivity and cycle life, so even an active material with poor conductivity or high capacity (large volume expansion) can be cycled. Good life characteristics.
- the ratio of the A component and the B component in the whole composite powder is preferably 40 to 95 mass% for the A component and 60 to 5 mass% for the B component, when the total amount of both is 100 mass%.
- a long-life type negative electrode having very excellent cycle life characteristics and a high-capacity type negative electrode having a very high capacity per active material weight are obtained. be able to.
- the composite powder it is sufficient that the A component and the B component exist as main component phases, and a very small amount of impurities may exist. Even a very small amount of impurities does not adversely affect cycle deterioration.
- the negative electrode for sodium secondary batteries of the present invention is a negative electrode for sodium secondary batteries using the negative electrode material for sodium secondary batteries. Therefore, it becomes a negative electrode for sodium secondary batteries which has a long life, a high charge / discharge capacity, and is easy to handle.
- the negative electrode for a sodium secondary battery of the present invention preferably contains a polyimide binder.
- a polyimide binder By using a polyimide binder, even when the volume expansion accompanying charging / discharging is large, the binding by the binder can be maintained.
- an aqueous binder can be used.
- the sodium secondary battery of this invention is a sodium secondary battery using the said negative electrode for sodium secondary batteries.
- the method for producing a negative electrode material for a sodium secondary battery of the present invention is as follows. (A) A step of preparing the component B raw material and solidifying the preparation by heat treatment (temperature 400 to 1100 ° C., treatment time 1 to 30 hours) to obtain the component B; (B) a step of combining the A component and the B component; It has. According to this method, the B component solidified by the step (A) can be obtained, and the B component and the A component solidified by the step (B) are combined, so that long charge and high charge / discharge A negative electrode for a sodium secondary battery that has a capacity and is easy to handle can be obtained.
- the step (B) is preferably a step of combining the A component and the B component by mechanical milling. Since the B component has a lower mechanical strength than the A component, the B component is more easily pulverized than the A component. Therefore, it is possible to coat the A component with the B component by pressing the B component powder that has become fine particles by mechanical milling onto the surface of the A component powder with a ball or the like.
- the step (B) may be a step in which the component A is dispersed in the melted component B, and a pulverization process is performed after cooling.
- the B component is less than the A component, the B component is difficult to be coated on the A component, but by adopting a method in which the A component is dispersed in the molten B component and pulverized after cooling, the B component is added to the A component. Can be reliably coated.
- a conductive assistant and / or a binder is added and the composite powder contains the conductive assistant and / or the binder.
- the conductivity of the obtained negative electrode material for a sodium secondary battery can be improved, and the cycle life characteristics and high rate discharge characteristics of the battery can be improved.
- the electrolyte is composed of a main solvent composed of ethylene carbonate (EC), propylene carbonate (PC), ethyl methyl carbonate (EMC), dimethyl carbonate (DMC), and diethyl carbonate (DEC).
- EC ethylene carbonate
- PC propylene carbonate
- EMC ethyl methyl carbonate
- DMC dimethyl carbonate
- DEC diethyl carbonate
- a sodium secondary battery in which NaPF 6 is dissolved in a mixed solvent composed of at least one selected sub-solvent is preferable.
- EC Since EC is usually solid at room temperature, EC alone does not function as an electrolyte, but it is selected from propylene carbonate (PC), ethyl methyl carbonate (EMC), dimethyl carbonate (DMC), and diethyl carbonate (DEC).
- PC propylene carbonate
- EMC ethyl methyl carbonate
- DMC dimethyl carbonate
- DEC diethyl carbonate
- concentration of the electrolytic solution is not particularly limited, but is preferably 0.1 to 3 mol / L, and more preferably 0.5 to 2 mol / L.
- the negative electrode material for sodium secondary batteries which can exhibit the outstanding cycling characteristics, maintaining its high discharge capacity, its manufacturing method, the negative electrode for sodium secondary batteries, and a sodium secondary battery are provided. it can.
- FIG. 3 is a diagram showing the cycle life of Example 1. It is the figure which showed the cycle life of Example 2. It is the figure which showed the cycle life of Example 3. It is the figure which showed the cycle life of Example 4. It is the figure which showed the cycle life of Example 5. It is the figure which showed the cycle life of Example 6. It is the figure which showed the cycle life of Example 7.
- FIG. 6 is a diagram showing the cycle life of Examples 2 to 5. It is the figure which showed the cycle life of Example 3, 6, 7 and the reference example 1.
- FIG. It is the figure which showed the cycle life of Example 8-1. It is the figure which showed the cycle life of Example 8-2. It is the figure which showed the cycle life of Example 9. It is the figure which showed the cycle life of Examples 10 and 11.
- FIG. 1 shows the cycle life of Example 2 to 5. It is the figure which showed the cycle life of Example 3, 6, 7 and the reference example 1.
- FIG. It is the figure which showed the cycle life of Example 8-1. It is the figure which showed the cycle life of Example 8-2. It is the figure which showed the cycle
- FIG. 4 is a diagram showing cycle life of Examples 1, 8-1 and Reference Example 2.
- 1 is a diagram showing a charge / discharge curve of Example 1.
- FIG. It is the figure which showed the charging / discharging curve of Example 2.
- FIG. It is the figure which showed the charging / discharging curve of Example 3.
- 6 is a diagram showing a charge / discharge curve of Example 5.
- FIG. It is the figure which showed the charging / discharging curve of Example 6.
- It is the figure which showed the charging / discharging curve of Example 7.
- FIG. It is the figure which showed the charging / discharging curve at the time of using antimony as a negative electrode active material in a lithium ion secondary battery
- the negative electrode material for sodium secondary battery (sodium ion secondary battery) of the present invention is It consists of a sulfide or sulfide complex containing sulfur and antimony. Furthermore, the following component (i) can be included as needed. (I) at least one element selected from the group consisting of Sn, As, Bi, Ge, Ga, Pb, and C; When component (i) is included, the proportions of the above components are sulfur: 10 to 70 mol%, antimony: 10 to 70 mol%, and (i): 3 to 60 mol%.
- the negative electrode material for a sodium secondary battery of the present invention two components of sulfur and antimony are essential components, and the component (i) is an optional component that is added as necessary.
- the ratio of sulfur to antimony is sulfur: 40 to 75 mol% and antimony: 25 to 60 mol%.
- the sulfide or sulfide composite becomes at least sodium sulfide (Na 2 S) in the process of initial charge (sodium ion occlusion), and does not react in the subsequent charge / discharge process. . That is, it is sodium-reduced and decomposes into at least a solid electrolyte layer.
- Na 2 S sodium sulfide
- SnO sodium oxide (Na 2 O), which is a solid electrolyte, is formed in the initial charging process.
- sodium oxide has poor ion conductivity, cycle life characteristics are poor.
- the sulfide and the like are decomposed into a sodium sulfide (Na 2 S) -based solid electrolyte in the initial charging process.
- the sodium sulfide (Na 2 S) -based solid electrolyte layer is a solid that can move sodium ions in the process of occlusion / release of sodium ions. Therefore, the negative electrode material for a sodium secondary battery of the present invention is decomposed into a sodium sulfide (Na 2 S) -based solid electrolyte having good ion conductivity in the initial charging process, so that even if it has a high capacity, it can be cycled. Good life characteristics.
- sulfur is an essential element for forming sodium sulfide in the initial charge
- antimony reversibly contains sodium. Not only does it have a role of occlusion / release, but the reason is not clear, but it makes the cycle life characteristics good.
- (I) has a role of reversibly occluding and releasing a large amount of sodium.
- antimony is not a negative electrode active material in a lithium ion secondary battery. According to the experiments by the present inventors, as shown in FIG. 25, the first cycle occludes lithium with a capacity exceeding 1000 mAh / g, but in the voltage range of 0-1 V (vs. Li + / Li), the negative electrode Does not function as an active material. From this, it can be said that the use of antimony as the negative electrode active material cannot be easily recalled.
- the amount of sulfur of 10 to 70 mol% is less than 10 mol%, because the amount of sodium sulfide-based solid electrolyte formed decreases, resulting in poor ion conductivity, and the volume of (i) accompanying charge / discharge.
- the amount of the buffer layer that absorbs expansion is small and the cycle life characteristics are poor, and if it exceeds 70 mol%, the amount of antimony and (i) is small, so the electrode has a small negative electrode capacity. This is because it is more preferably 20 to 65 mol%, and further preferably 30 to 60 mol%.
- the reason why the antimony is 10 to 70 mol% is that if it is less than 10 mol%, not only the electrode has a small negative electrode capacity, but also the cycle life characteristics become poor, and if it exceeds 70 mol%, the amount of sulfur is small.
- the amount of sodium sulfide-based solid electrolyte is reduced, resulting in poor ionic conductivity, and an electrode with poor cycle life characteristics due to a small amount of buffer layer that absorbs the volume expansion of (i) associated with charge / discharge. This is also not preferable, and is more preferably 20 to 65 mol%, and further preferably 30 to 60 mol%.
- (i) is 3 to 60 mol% is that if it is less than 3 mol%, the electrode has a small negative electrode capacity, and if it exceeds 60 mol%, the amount of sulfur is small. Cycle, because the ion conductivity becomes poor, the amount of the buffer layer that absorbs the volume expansion of (i) accompanying charge / discharge is small, the electrode has poor cycle life characteristics, and the amount of antimony is also small. This is because the electrode has poor life characteristics and is not preferable in any case, and is more preferably 20 to 55 mol%, and further preferably 30 to 50 mol%.
- the sulfide or the like constituting the negative electrode material for a sodium secondary battery of the present invention is preferably vitrified, and can be vitrified by containing Ge.
- Ge has a role of forming a glass skeleton structure.
- the Ge content is preferably 0.5 to 40 mol%, more preferably 1 to 20 mol%. If the Ge content is less than 0.5 mol%, vitrification may not be sufficiently performed. If the Ge content exceeds 40 mol%, the amount of antimony decreases, resulting in poor cycle life characteristics. Since the amount of i) is reduced, the electrode has a small negative electrode capacity. Further, since Ge is an expensive element, it becomes an expensive electrode, which is not preferable in any case.
- the sulfide composite includes a composite of two or more sulfides.
- the method for producing the sulfide composite constituting the negative electrode material for a sodium secondary battery of the present invention is not particularly limited.
- a predetermined amount of each component raw material is enclosed in a quartz ampule, and the content enclosed by heat treatment is contained. It can be produced by vitrification.
- raw materials in addition to the essential components of sulfur (S) and antimony (Sb), as an optional component (i) as required, simple metals such as Sn, Bi, Ge, Ga, Pb, or sulfides thereof Alternatively, nonmetals such as As and C (hard carbon etc.) can be used.
- the quartz ampoule to be used is sufficiently dried by a vacuum dryer. Further, during vitrification, it is preferable to heat at 400 to 1100 ° C., more preferably at 600 to 800 ° C.
- the heat treatment time may be a time during which the content enclosed in the quartz ampoule is sufficiently vitrified, but is generally preferably 1 to 30 hours, more preferably 5 to 24 hours. By heating at a temperature of 400 to 1100 ° C. for 1 to 30 hours, the above contents can be vitrified sufficiently.
- the sulfide constituting the negative electrode material for a sodium secondary battery of the present invention is vitrified, it is excellent in water resistance, so that it can be handled in air and use a water-based binder that was not possible with conventional sulfides. .
- the sulfide having the above composition can be further improved in conductivity by forming a conductive coating with a conductive metal, carbon or the like. Thereby, it has a more favorable battery characteristic as a negative electrode active material for sodium batteries.
- Known methods such as sputtering, vapor deposition, mechanical alloy (MA), rotary kiln, and electroless plating can be used as a method for forming a conductive coating such as a conductive metal or carbon on sulfide.
- the coating amount of the conductive coating if it is too small, the effect of improving the conductivity is not sufficient, while if it is too large, the surface such as sulfide is almost covered and it becomes difficult to occlude / release sodium ions. Absent.
- the coating amount of the conductive coating is preferably about 0.1 to 30 parts by weight, more preferably about 0.5 to 25 parts by weight with respect to 100 parts by weight of sulfide or the like. More preferably, it is about 1 to 10 parts by weight.
- the carbon precursor used in this method may be an organic material that is carbonized by heating.
- a sticky hydrocarbon-based organic material coal-based pitch, petroleum-based pitch, or the like can be used.
- examples of the sticky hydrocarbon organic substance include phenol resin, furan resin, citric acid, PVA, and urushiol.
- the heating temperature may be any temperature at which the carbon precursor is carbonized, and is preferably about 300 to 1100 ° C., and more preferably about 500 to 900 ° C. In this case, if the heating temperature is too low (less than 300 ° C.), the carbon precursor is difficult to be carbonized. On the other hand, if the heating temperature is too high (over 1100 ° C.), sulfides react with carbon, In addition, there is a possibility that it will occur, and the apparatus becomes large and the cost increases, which is not preferable.
- the heat treatment time may be a time for carbonization of the carbon precursor, and is usually about 1 to 24 hours. If the heating time is too short, the carbon precursor is not sufficiently carbonized, which is not preferable because the negative electrode has poor electron conductivity.
- the atmosphere during the carbonization treatment may be a non-oxidizing atmosphere such as an inert atmosphere or a reducing atmosphere.
- the atmosphere may be He (helium), Ne (neon), Ar (argon), N 2 (nitrogen), H 2 (hydrogen), or the like.
- any of the sulfides described above and sulfides having a conductive coating formed thereon can be effectively used as the negative electrode active material for sodium secondary batteries.
- the negative electrode material for a sodium secondary battery of the present invention may be the above sulfide alone, but a material capable of electrochemically occluding and releasing sodium (hereinafter referred to as A component) and the above sulfide. Etc. (hereinafter referred to as “component B”).
- a component a material capable of electrochemically occluding and releasing sodium
- component B a material capable of electrochemically occluding and releasing sodium
- the negative electrode material for a sodium secondary battery of the present invention is a composite powder of component A and component B
- it can be produced by a production method comprising the following steps (A) and (B).
- step (B) a step of combining the A component and the B component by mechanical milling, a step of dispersing the A component in the molten B component, and performing a pulverization process after cooling can be employed. These steps (B) will be described in detail later.
- the A component is not particularly limited as long as it can occlude sodium ions in the initial charge and can occlude and release sodium ions during the subsequent charge and discharge.
- At least one or more elements selected from the above, alloys using these elements, oxides, chalcogenides or halides are preferred.
- the element is preferably Zn, Ge, Ag, Sn, Bi or the like, and the alloy is Al—Ge, Si—Ge, Si—Sn, Zn—Sn, Ge—Ag, Ge—.
- the oxide is preferably SnO, SnO 2 , SnC 2 O 4 , GeO, etc.
- the chalcogenide, SnS, SnS 2 and the like are preferable, and as the halide, SnF 2 , SnCl 2 , SnI 2 , SnI 4 and the like are preferable.
- the above-mentioned component A may be used alone or in combination of two or more.
- the ratio of the A component and the B component is preferably 5 to 80 mass% for the A component and 95 to 20 mass% for the B component, and 20 to 70 mass% for the A component when the total amount of both is 100 mass%.
- B component is more preferably 80 to 30 mass%.
- the capacity per weight of the active material is 200 to 400 mAh / g and the cycle life characteristics are very good, it is promising as a long-life type negative electrode.
- the capacity per active material weight is very high, 300 to 700 mAh / g. Promising.
- the A component and the B component may be present as main component phases, and even if a very small amount of impurities is present, cycle deterioration is not adversely affected.
- the B component undergoes phase separation into sodium sulfide, antimony, and tin by Na reduction during the initial charging (Na storage) process.
- Sodium sulfide does not participate as an active material under the condition of 0 to 1 V (vs. Na + / Na), and therefore does not participate in the subsequent charge / discharge reaction.
- the ionic conductivity of the phase-separated Sb, Sn, and A components that exist as a skeleton in the composite powder and participate in the charge / discharge reaction is improved, and even if the phase-separated Sb, Sn, and A components change in volume.
- the volume change of the composite powder as a whole can be effectively suppressed.
- Na 2 S produced in the charging process is excellent in ionic conductivity.
- the A component is a metal component that mainly reacts with Na and has excellent electrical conductivity. Therefore, in the charge and discharge process of the composite powder constituting the negative electrode material for sodium secondary battery of the present invention, excellent conductivity is obtained in terms of both ion conductivity and electrical conductivity.
- the A component and phase-separated Sb and Sn become Na-converted phases as Na is further occluded, and become reversible capacitive component phases.
- the negative electrode material for a sodium secondary battery of the present invention composed of the above composite powder has a large reversible electric capacity possessed by phase-separated Sb, Sn and A components, and Na 2 which is a solid electrolyte layer / buffer layer.
- the irreversible component of the S phase By having a skeletal structure of the irreversible component of the S phase, it exhibits excellent characteristics such as high capacity and cycle life.
- the surface of the A component is preferably coated with the B component.
- the reason for this is that the presence of the B component around the A component nucleus improves the ionic conductivity of the A component associated with sodium absorption / release (charging / discharging) and cracks caused by expansion / contraction. This is because it can be suppressed.
- the A component alone can improve the ionic conductivity and cycle characteristics even with an active material with poor ion conductivity and cycle life, so even an active material with poor conductivity or high capacity (large volume expansion) can be used. Good cycle life characteristics.
- the A component may be the primary particles themselves or may be aggregated secondary particles or the like.
- the B component may be completely coated on the entire surface of the A component, or may be coated only on a part of the A component. When only a part of the A component is coated, 20% or more of the surface area of the A component may be covered with the B component.
- the ratio of the A component covered with the B component can be measured, for example, by using a scanning electron microscope (SEM) photograph.
- the method for coating the B component on the surface of the A component is not particularly limited.
- a method in which a raw material containing the A component and the B component is mixed and a mechanical milling process is performed.
- Mechanical milling is a method of applying external forces such as impact, tension, friction, compression, and shear to the raw material powder (at least component A and component B), including a rolling mill, vibration mill, planetary mill, rocking mill, Examples include a method using a horizontal mill, an attritor mill, a jet mill, a crusher, a homogenizer, a fluidizer, a paint shaker, a mixer and the like.
- the raw material powder in the method using a planetary mill, can be pulverized / mixed or subjected to solid phase reaction by mechanical energy generated by putting both the raw material powder and balls in a container and rotating and revolving. According to this method, it is known that the material is pulverized to the nano order.
- the raw material powder of the negative electrode material contains at least an A component and a B component. Since the B component has lower mechanical strength than the A component, the B component is more easily pulverized than the A component. Therefore, the B component powder that has become fine particles can be pressure-bonded to the surface of the A component powder with a ball or the like, and the A component can be coated with the B component.
- the method of coating the B component on the surface of the A component there is a method in which the A component is dispersed in the molten B component and pulverized after cooling.
- the B component is less than the A component, it is difficult to coat the B component on the A component by the above-described mechanical milling method, so this method (dispersing the A component in the molten B component and grinding after cooling) It is preferable to employ the method.
- the conditions for melting the B component are not particularly limited, but if the heating temperature is less than 400 ° C., it is difficult to melt, and the B component may be decomposed at a temperature exceeding 1100 ° C. Therefore, the heating temperature is about 400 to 1100 ° C., more preferably 500 to 900 ° C.
- a conductive additive may be contained in the B component.
- the conductive assistant may be dispersed in the state where the B component is melted.
- the conductivity can be improved, and the cycle life characteristics and high rate discharge characteristics of the battery can be greatly improved.
- a conductive support agent may be contained in B component, and a conductive support agent may be contained in B component in both (A) process and (B) process.
- a metal, a conductive polymer, etc. may react with B component, it is preferable to use carbon black.
- carbon black include acetylene black (AB), ketjen black (KB), carbon fiber (VGCF), carbon nanotube (CNT), graphite, soft carbon, hard carbon, mesoporous carbon, graphene, vapor grown carbon, and the like. It is done.
- a carbon precursor may be used as a conductive additive.
- the conductive assistant is preferably contained in an amount of 0.1 to 10 wt%, more preferably 0.5 to 5 wt%.
- the content is 0.1 to 10 wt%, a sufficient conductivity improvement effect can be obtained, high-rate discharge characteristics can be improved, and a decrease in capacity due to the drop of the B component from the A component is minimized. Can be suppressed.
- a highly cohesive conductive agent such as carbon black
- a sodium secondary battery using the above-described composite powder as a negative electrode material for a sodium battery has a high capacity, good cycle life characteristics, and excellent water resistance.
- the above-mentioned sulfides for example, antimony sulfide and sulfide glass
- sulfides having a conductive coating formed thereon are also effectively used as a negative electrode material for sodium batteries. it can.
- the negative electrode material for a sodium secondary battery can be made to function well.
- the deposition is to fix the current collector in contact with the negative electrode material of the present invention. That is, filling of the negative electrode material, fixing of the negative electrode material by a metal net as a current collector, and the like are applicable.
- the deposition method is not particularly limited, and examples thereof include a pressure bonding method, a slurry method, a paste method, an electrophoresis method, a dipping method, a spin coating method, and an aerosol deposition method.
- a metal foam such as foamed nickel is used as a current collector
- a slurry method or a paste method is preferable from the viewpoints of packing density, electrode production rate, and the like.
- the negative electrode may contain, in addition to the negative electrode material of the present invention, a conductive auxiliary agent for imparting conductivity and a binder for imparting binding properties as necessary.
- a conductive support agent, a binder, etc. are contained in B component by putting a conductive support agent, a binder, etc. in the said (A) process and / or (B) process at the time of manufacture of negative electrode material.
- a conductive additive, a binder, and the like may be further included in the production of the negative electrode using the negative electrode material.
- a suitable solvent N-methyl-2-pyrrolidone (NMP), water, alcohol, xylene, toluene, etc.
- NMP N-methyl-2-pyrrolidone
- the negative electrode mixture paste composition, the negative electrode mixture slurry, and the like obtained by sufficiently kneading and applying to the surface of the current collector are dried, and further pressed to form a negative electrode material-containing layer on the current collector surface. It can be formed into a negative electrode.
- a known sodium secondary battery element positive electrode, separator, electrolyte, etc.
- a square, cylindrical, or coin type is used in accordance with a conventional method. What is necessary is just to assemble to a sodium secondary battery.
- the conductive auxiliary agent those usually used, for example, those described above can be used, and when the carbon material is included, the type (structure, etc.) of the carbon material is not particularly limited.
- carbon materials such as acetylene black (AB), ketjen black (KB), graphite, carbon fiber, carbon tube, graphene, and amorphous carbon may be used alone or in combination of two or more. May be. More preferably, those capable of forming a conductive three-dimensional network structure in the composite powder (for example, flaky conductive material (flaked copper powder, flake nickel powder, etc.), carbon fiber, carbon tube, amorphous carbon, etc.) Is preferred. If a conductive three-dimensional network structure is formed, a sufficient current collecting effect can be obtained as a negative electrode material for sodium secondary batteries, and the volume expansion of electrodes (particularly alloy components) during Na occlusion can be effectively suppressed. it can.
- Binders are also commonly used, such as polyvinylidene fluoride (PVdF), polytetrafluoroethylene (PTFE), polyimide (PI), polyamide, polyamideimide, polyacryl, styrene butadiene rubber (SBR), styrene-ethylene- Materials such as butylene-styrene copolymer (SEBS), carboxymethylcellulose (CMC), polyacryl, PVA, PVB and EVA may be used alone or in combination of two or more.
- PVdF polyvinylidene fluoride
- PTFE polytetrafluoroethylene
- PI polyimide
- SBR styrene butadiene rubber
- SEBS styrene-ethylene- Materials
- CMC carboxymethylcellulose
- PVA polyacryl
- PVB and EVA may be used alone or in combination of two or more.
- the binder used is preferably PI.
- the negative electrode material-containing layer of the negative electrode for example, the negative electrode material of the present invention is preferably 50 to 99 mass%, the conductive auxiliary agent amount is 0.5 to 40 mass%, and the binder amount is preferably 0.5 to 30 mass%.
- the thickness of the negative electrode material-containing layer of the negative electrode is preferably 0.5 to 200 ⁇ m, for example, although it depends on the electrode capacity density. By setting the thickness of the negative electrode material-containing layer within this range, a practical electric capacity can be obtained while the current collector supports the negative electrode material.
- the current collector is not particularly limited as long as it is a material having electronic conductivity and capable of energizing the held negative electrode material.
- conductive materials such as C, Cu, Al, Ti, Cr, Ni, Mo, Ru, Rh, Ta, W, Os, Ir, Pt, Au, and alloys containing two or more of these conductive materials ( For example, stainless steel) can be used.
- the current collector is preferably C, Cu, Al, Ti, Cr, Ni, Cu, Au, stainless steel, etc., and from the viewpoint of material cost. C, Cu, Al, Ni, Cu, stainless steel and the like are preferable.
- the current collector is easily sulfided during the heat treatment, and the mechanical strength may be significantly reduced. Therefore, the current collector is preferably C, Al, or stainless steel, which does not easily react with sulfur.
- the shape of the current collector includes linear, rod-like, plate-like, foil-like, net-like, woven fabric, non-woven fabric, expanded, porous body or foam, among which the packing density can be increased and the output characteristics are good. Therefore, an expand, a porous body or a foam is preferable.
- sodium cobaltate (NaCoO 2 ), sodium nickelate (NaNiO 2 ), cobalt manganese sodium nickelate (NaCo 0.33 Ni 0.33 Mn 0.33 O 2 ), sodium manganate (NaMn 2 O 4) ), Sodium ferrate (NaFeO 2 ), sodium iron phosphate (NaFePO 4 ), vanadium oxide-based materials, sulfur-based materials, graphite and the like are used.
- a separator what is used for a well-known lithium secondary battery and a sodium secondary battery can be used.
- a porous sheet made of a resin such as polyethylene (PE), polypropylene (PP), polyester, cellulose, and polyamide, a glass filter, a nonwoven fabric, and the like can be used, but the invention is not limited thereto.
- the electrolyte needs to contain sodium ions, the electrolyte is not particularly limited as long as it is used in a sodium secondary battery, but a sodium salt is preferable as the electrolyte salt.
- the sodium salt include NaPF 6 , NaBF 4 , NaClO 4 , NaTiF 4 , NaVF 5 , NaAsF, NaSbF 6 , NaCF 3 SO 3 , Na (C 2 F 5 SO 2 ) 2 N, NaB (C 2 O 4 ) 2 , NaB 10 Cl 10 , NaB 12 Cl 12 , NaCF 3 COO, Na 2 S 2 O 4 , NaNO 3 , Na 2 SO 4 , NaPF 3 (C 2 F 5 ) 3 , NaB (C 6 F 5 ) 4 and salts such as Na (CF 3 SO 2 ) 3 C can be used.
- 1 type may be used independently among the said salts, and 2 or more types may be combined.
- the sodium salt has high electronegative properties and is easily ionized, it has excellent charge / discharge cycle characteristics and can improve the charge / discharge capacity of the secondary battery.
- the electrolyte salt NaPF 6 is preferred. By using NaPF 6 as a salt, the effect of improving the discharge capacity and cycle life of the positive electrode and improving the cycle life of the negative electrode is enhanced.
- the concentration of the electrolytic solution (the concentration of salt in the solvent) is not particularly limited, but is preferably 0.1 to 3 mol / L, and more preferably 0.5 to 2 mol / L.
- solvent for the electrolyte examples include propylene carbonate (PC), ethylene carbonate (EC), dimethyl carbonate (DMC), diethyl carbonate (DEC), ethyl methyl carbonate (EMC), ⁇ -butyrolactone, 2-methyltetrahydrofuran, 1,3 -The group consisting of dioxolane, 4-methyl-1,3-dioxolane, 1,2-dimethoxyethane, 1,2-diethoxyethane, diethyl ether, sulfolane, methyl sulfolane, nitromethane, N, N-dimethylformamide, dimethyl sulfoxide At least one selected from the group consisting of ethylene carbonate and diethyl carbonate, or ⁇ -butyrolactone alone is particularly suitable.
- PC propylene carbonate
- EC ethylene carbonate
- DMC dimethyl carbonate
- DEC diethyl carbonate
- EMC ethyl methyl carbonate
- the mixing ratio of the mixture of ethylene carbonate and diethyl carbonate can be arbitrarily adjusted in the range of 10 to 90 vol% for both ethylene carbonate and diethyl carbonate.
- the electrolyte solution solvent is preferably a solvent containing EC.
- a solvent containing EC By using a solvent containing EC, the effect of improving the cycle life of the negative electrode is enhanced.
- EC is solid at room temperature, EC alone does not function as an electrolyte.
- a mixed solvent with PC, DMC, DEC, EMC, etc. it functions as an electrolyte that can be used even at room temperature.
- a solid electrolyte may be used without using a solvent.
- it does not specifically limit as a structure of a sodium secondary battery, It can apply to the existing battery forms and structures, such as a laminated type battery and a wound type battery. According to the sodium secondary battery having the above structure, it functions as a secondary battery.
- sulfides 1 to 9 having the compositions shown in Table 1 were prepared.
- sulfide 1 or the like commercially available antimony sulfide (Sb 2 S 3 ) (manufactured by Kojundo Chemical Co., Ltd.) was used.
- Sb 2 S 3 commercially available antimony sulfide
- the raw materials were prepared according to the formulation shown in Table 1 below, and the formulation was melted by heat treatment to produce sulfide glass.
- the heat treatment condition was that the preparation was heated to a predetermined temperature at a heating rate of 20 ° C./hour and then held at that temperature for 12 hours. Then, it cooled naturally to room temperature and manufactured. It was confirmed that the obtained sulfides 2 to 8 were vitrified by XRD measurement using an X-ray diffractometer. In addition, sulfide etc. 1 and sulfide etc. 9 are not vitrified.
- Example 1 to 16 Reference Examples 1 to 3> Using the A component and / or B component shown in Table 2 below as starting materials, pulverization or milling (normal temperature, normal pressure, argon gas atmosphere) was performed using a planetary ball mill in zirconia balls and containers. . Table 2 shows the starting materials used in Examples 1 to 16 and Reference Examples 1 to 3, the mixing ratio of the A component and the B component, and the synthesis conditions (gravity acceleration, time). In Examples 6 to 11 and Example 16, composite powders in which the surface of the A component was coated with the B component were obtained by milling the A component and the B component. Since Examples 1 to 5 and 12 to 15 were only the B component, and Reference Examples 1 to 3 were only the A component, powders containing only the A or B component were obtained by pulverization.
- a negative electrode active material 80 wt%, PI binder 15 wt%, KB 5 wt% were mixed to prepare a slurry mixture, After coating and drying on the metal foil, the metal foil and the coating film were tightly bonded with a roll press, and then heat-treated (under reduced pressure at 200 ° C. for 1 hour or longer) to obtain a test electrode (negative electrode).
- the metal foils copper foils (thickness 43 ⁇ m) were used for Examples 1 to 5, 12 to 15 and Reference Examples 1 to 3, and aluminum foils (thickness 20 ⁇ m) were used for Examples 6 to 11 and 16.
- Example 8 what used copper foil (thickness 20 micrometers) was produced on the same conditions.
- the one using the copper foil is referred to as Example 8-1 and the one using the aluminum foil is referred to as Example 8-2.
- Metal sodium foil (diameter 13 mm x thickness 0.5 mm) as a counter electrode, glass filter (GA100) as a separator, and NaPF 6 as an electrolyte solution dissolved in a mixed solvent of EC: DMC (1: 1 vol%)
- a test cell (coin cell (CR2032)) having (concentration: 1 mol / L) was prepared.
- Cycle life characteristics The produced test cell (sodium secondary battery) was subjected to a charge / discharge test at a rate of 0.5C. The cut-off potential was set to 0-1 V (vs. Na + / Na). Table 3 summarizes the cycle life of Examples 1 to 16 and Reference Examples 1 to 3. The cycle lives of Examples 1 to 7 are shown in FIGS. 1 to 7, respectively. The cycle lives of Examples 2 to 5 are collectively shown in FIG. 8, and the cycle lives of Examples 3, 6, 7 and Reference Example 1 are summarized. FIG. The cycle lives of Examples 8-1, 8-2, 9, 10 and 11 are shown in FIGS. 10 to 13, respectively, and the cycle lives of Examples 1, 8-1 and Reference Example 2 are collectively shown in FIG. The charge / discharge curves of Examples 1 to 7 are shown in FIGS. 15 to 21, respectively, and the charge / discharge curves of Examples 8-1, 8-2, and 9 are shown in FIGS. 22 to 24, respectively.
- Example 1 The capacity of Example 1 is as low as about 200 mAh / g, but the cycle life characteristics are stable, and the cycle life characteristics are lower than those of Sn alone (Reference Example 1) or Sb alone (Reference Example 3). It is good. (See Figures 1, 9, 15 and Table 3) (2) Although the cycle life characteristic of Example 2 is better than that of Sn alone (Reference Example 1) or Sb alone (Reference Example 3), the capacity is decreased after 40 cycles. (See Figure 2, Figure 9, Figure 15, Table 3) (3) Example 3 has better cycle life characteristics than Examples 1 and 2. This is considered to be due to containing Ge.
- Example 4 (See Figs. 3, 8, and 17) (4) It can be seen that the cycle life characteristics of Example 4 are better than those of Examples 1 and 2, and the cycle life characteristics are good even when the Sb amount of Example 3 is increased. (See FIGS. 4, 8, and 18) (5) In Example 5, the active material capacity increases as the cycle progresses. (See FIGS. 5, 8, and 19) (6) The cycle life characteristics of Examples 2 to 5 are good in the order of Example 2 ⁇ Example 5 ⁇ Example 4 ⁇ Example 3. (See Figure 8) (7) In Example 6, the active material capacity is increased as compared with Example 3. Thereby, it turns out that active material capacity
- Example 7 Although the active material capacity of Example 7 was larger up to 10 cycles (500 to 600 mAh / g) than that of Example 6, the cycle life characteristics deteriorated. From this, it can be seen that when the amount of Sn compounded with sulfide or the like becomes excessive, the cycle life characteristics deteriorate. (See FIGS. 7, 9, and 21)
- Example 8-1 a high active material capacity of 300 mAh / g or more is stably maintained over a long cycle. Therefore, even when sulfide 1 or the like (Sb 2 S 3 ) which is not vitrified is used as a raw material, the active material capacity and cycle life are obtained by compounding the sulfide or the like with another raw material (Sn). It can be seen that the characteristics are greatly improved. (See FIGS.
- Example 8-2 the current collector was made of aluminum for the purpose of suppressing the electrode deterioration of Example 8-1, but a high active material capacity of 300 mAh / g or more was maintained over a long cycle. It was stably maintained, and even after 150 cycles of charge and discharge were repeated, the deterioration was small, and the current collector was not deteriorated. (See FIGS. 11 and 23) (11) In Example 9, the irreversible capacity is reduced compared to Example 8. This is considered to be due to an increase in the amount of Sn. Moreover, the multistage plateau became remarkable by increasing Sn amount. (See FIGS.
- Examples 10 and 11 have low capacities of about 200 mAh / g and about 250 mAh / g, respectively, but the cycle life characteristics are stable, and the cycle life characteristics are higher than those of Sn alone (Reference Example 1). It is good. (See Figure 13)
- the sodium secondary battery using the sulfide or the like which is the negative electrode material of the present invention has cycle life characteristics as compared with the case where Sn is used as the negative electrode active material.
- the cycle life characteristics are further improved by containing Ge, and by combining sulfides and other components (Sn, SnS, Ge, etc.) (Examples 6 to 11),
- the material capacity increases, and a sodium secondary battery capable of exhibiting excellent cycle characteristics while maintaining a high discharge capacity is obtained.
- the secondary battery using the negative electrode for sodium secondary battery of the present invention has a high energy density and good cycle life characteristics, so that it can be used as a power source for electric tools, automobiles, etc. It can be used for applications such as products or vehicles. It can also be used as a backup power source.
- air conditioners washing machines, TVs, refrigerators, freezers, air conditioners, laptop computers, computer keyboards, computer displays, desktop computers, laptop computers, CRT monitors, personal computers Rack, printer, integrated computer, mouse, hard disk, computer peripherals, iron, clothes dryer, window fan, walkie-talkie, blower, ventilator, TV, music recorder, music player, oven, range, toilet seat with washing function, hot air Heater, Car component, Car navigation system, Flashlight, Humidifier, Portable karaoke machine, Exhaust fan, Dryer, Dry cell, Air purifier, Mobile phone, Emergency light, Game machine, Sphygmomanometer, Coffee mill, Coffee maker, Kotatsu, Copy machine , Disc changer, la Oh, shaver, juicer, shredder, water purifier, lighting equipment, dehumidifier, dish dryer, rice cooker, stereo, stove, speaker, trouser press, vacuum cleaner, body fat scale, weight scale, health meter, movie player, electric Carpet, electric
- the negative electrode for sodium secondary battery obtained by the present invention has a high capacity and good cycle life characteristics, and a sodium secondary battery using the negative electrode can withstand practical use.
- Sodium is an element that is inexpensive and readily available, has no local uneven distribution like lithium resources, and because sodium ion batteries can use inexpensive aluminum foil as a negative electrode current collector, If it can be replaced with a lithium ion secondary battery that is the mainstream of secondary batteries, it will be possible to manufacture secondary batteries at a lower cost than before.
- the present invention greatly contributes to further development of the secondary battery market.
Landscapes
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- General Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Inorganic Chemistry (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Physics & Mathematics (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- General Physics & Mathematics (AREA)
- Composite Materials (AREA)
- Battery Electrode And Active Subsutance (AREA)
- Secondary Cells (AREA)
Abstract
Description
例えば、現行のリチウムイオン電池は、一般に正極にはコバルト酸リチウム(LiCoO2)、ニッケル酸リチウム(LiNiO2)、燐酸鉄リチウム(LiFePO4)等のリチウム含有遷移金属複合酸化物が用いられ、負極には、リチウムの吸蔵および放出が可能なグラファイト、ハードカーボン等が用いられる。また、リチウムイオン電池に使用される電解液は、主として、プロピレンカーボネート(PC)、エチレンカーボネート(EC)等の環状カーボネートと、ジメチルカーボネート(DMC)、ジエチルカーボネート(DEC)、メチルエチルカーボネート(MEC)等の鎖状カーボネートとの混合有機溶媒に四フッ化ホウ酸リチウム(LiBF4)、六フッ化リン酸リチウム(LiPF6)、六フッ化砒酸リチウム(LiAsF6)、過塩素酸リチウム(LiClO4)、リチウムビストリフルオロメタンスルホニルアミド(LiN(CF3SO2)2)、三フッ化メタンスルホン酸リチウム(LiCF3SO3)等の電解質塩を溶解させたものが使用されている。
例えば、リチウムイオン電池は、リチウムイオンが負極活物質であるグラファイトと正極活物質であるLiCoO2等のリチウム含有遷移金属酸化物間を相互に移動し、各々の材料の分子間に移動するインターカレーション現象を起こすことで充放電を行う。グラファイトは、層状の分子構造であり、この層間にリチウムイオンが出入りしてもグラファイトの構造が破壊されることが少ない。また、理論上372mAh/gのリチウムイオンが吸蔵できる。
しかし、ナトリウムイオンは、イオン半径が大きく、グラファイト層間に進入できないため、容量を示さない。
特許文献2には、負極に直径0.1μm~1.0μmの繊維状炭素材料を用いたナトリウムイオン二次電池に関する発明が記載されている。
しかし、特許文献2に記載される直繊維状炭素材料を用いた負極の場合、サイクル寿命は良好であるが、エネルギー密度が小さいという問題がある。
非特許文献1には、リチウムイオン電池で一般的に用いられるEC:DMC系において、ナトリウムセルのハードカーボン電極は良好なサイクル特性を得ることができなかったことが示され、PC系の電解液がEC:DMCやPC:DMC系よりも良好なサイクル特性が得られる旨の結果が報告されている。
すなわち、特許文献3および非特許文献1には、電解液に負極のサイクル特性が大きく依存することが示されている。
特許文献4には、Sn単体またはGe単体を含む負極を用いた非水電解質二次電池において、非水電解質にナトリウムイオンが含まれる例が開示されている。
特許文献4に記載されるSn単体またはGe単体を含む負極の場合、充電・放電時に起こるナトリウム吸蔵・放出により、大きな体積膨張・収縮を生じる。その結果、電極そのものが瓦解することがあり、サイクル寿命が悪いという問題がある。また、電解液の検討はなされていない。
更に、必要に応じて下記(i)の成分を含み、
(i)Sn、As、Bi、Ge、Ga、Pb、Cからなる群から選択される少なくとも一種以上の元素、
成分(i)を含む場合、上記各成分の割合が、硫黄:10~70モル%、アンチモン:10~70モル%、(i):3~60モル%である。
ここで、「複合体」とは、各成分が結合している粒子から構成されているものを指し、各成分の粒子が単に集合して構成されている「混合体」とは異なる概念である。具体的には、硫化物複合体は、硫化物ガラスや結晶硫化物、硫化物アモルファス体等の硫化物の固溶体、硫化物の被覆体(硫化物が非硫化物の一部又は全部を被覆しているもの)、硫化物の焼成体等を含む。
Geはガラスの骨格構造を形成する役割があるため、ガラス化された負極材料を得ることができる。
ガラス化することで、耐水性及び耐酸性を有し、水或いは酸素と容易に反応することがなく、イオン伝導性の低下が生じることがなく、取り扱いも容易になる。更に、水系バインダーを用いることができるとともに、各々の製造工程をドライ雰囲気下とする必要がなく、製造コストを削減することができる。すなわち、ガラス化することが好ましい。
(1)A成分が、ナトリウムを電気化学的に吸蔵及び放出することができる材料、
(2)B成分が、上記硫化物又は硫化物複合体、
ここで、「複合粉末」は「混合粉末」とは異なる概念であり、混合粉末がA成分の粉末とB成分の粉末の単なる集合であるのに対し、複合粉末は当該粉末を構成する1つの粒子中にA成分とB成分の両方が含有されている。言い換えれば、複合粉末とは、A成分とB成分が結合(一体化)しているものであり、例えば、A成分にB成分(又はその逆)が被覆されている形態や担持されている形態が含まれる。
A成分を核としてその周囲(表面)にB成分が存在することで、ナトリウムの吸蔵・放出(充電・放電)に伴うA成分のイオン伝導性を向上させることができる。また、膨張・収縮に起因する割れを抑制することができる。これにより、A成分のみではイオン伝導性やサイクル寿命が乏しい活物質でもイオン伝導性とサイクル特性を向上させることができるので、導電性が乏しい或いは高容量な(体積膨張の大きな)活物質でもサイクル寿命特性が良好なものとなる。
このような割合においてA成分とB成分の割合を調整することにより、サイクル寿命特性に非常に優れた長寿命タイプの負極や、活物質重量当たりの容量が非常に高い高容量タイプの負極を得ることができる。
尚、上記複合粉末中には、A成分とB成分が主成分相として存在していればよく、ごく微量の不純物が存在してもよい。ごく微量の不純物が存在してもサイクル劣化には悪影響を及ぼさない。
そのため、長寿命で高い充放電容量を有し、しかも取り扱いが容易であるナトリウム二次電池用負極となる。
本発明のナトリウム二次電池用負極材料の製造方法は、
(A)上記B成分の原料を調合し、熱処理(温度400~1100℃、処理時間1~30時間)により調合物を固溶化させB成分を得る工程、
(B)上記A成分と上記B成分を複合化させる工程、
を備えている。
この方法によれば、(A)工程により固溶化されたB成分を得ることができ、(B)工程により固溶化されたB成分とA成分とを複合化するため、長寿命で高い充放電容量を有し、しかも取り扱いが容易であるナトリウム二次電池用負極を得ることができる。
B成分は、A成分と比べて機械的強度が低いため、A成分よりもB成分が粉砕されやすい。そのため、メカニカルミリングにより微粒子となったB成分粉末がA成分粉末の表面にボール等により圧着して、A成分にB成分を被覆することが可能である。
B成分がA成分よりも少ない場合には、A成分にB成分が被覆されにくいが、溶融したB成分にA成分を分散させ、冷却後粉砕する方法を採用することにより、A成分にB成分を確実に被覆することが可能となる。
複合粉末に導電助剤を含有させることにより、得られるナトリウム二次電池用負極材料の導電性を向上させることができ、電池のサイクル寿命特性、高率放電特性を向上させることが可能となる。
電解液溶媒としてECを含有する溶媒を用いることで、負極のサイクル寿命を改善する効果が高まる。通常、ECは常温では固体であるため、EC単独では電解液としての機能を果たさないが、プロピレンカーボネート(PC)、エチルメチルカーボネート(EMC)、ジメチルカーボネート(DMC)およびジエチルカーボネート(DEC)から選択される一種以上の溶液との混合溶媒とすることで、常温でも使用可能な電解液として機能する。
電解液の塩としてNaPF6を用いることで、負極のサイクル寿命を改善する効果が高まる。また、電解液の濃度(溶媒中の塩の濃度)は、特に限定されないが、0.1~3mol/Lであることが好ましく、0.5~2mol/Lであることが更に好ましい。
本発明のナトリウム二次電池(ナトリウムイオン二次電池)用負極材料は、
硫黄と、アンチモンと、を含む硫化物又は硫化物複合体からなる。
更に、必要に応じて下記(i)の成分を含むことができる。
(i)Sn、As、Bi、Ge、Ga、Pb、Cからなる群から選択される少なくとも一種以上の元素、
成分(i)を含む場合、上記各成分の割合が、硫黄:10~70モル%、アンチモン:10~70モル%、(i):3~60モル%である。
(i)の成分を含まない場合、硫黄とアンチモンの割合は、硫黄:40~75モル%、アンチモン:25~60モル%となる。
例えば、SnOの場合、初期の充電の過程で、固体電解質である酸化ナトリウム(Na2O)を形成する。しかし、酸化ナトリウムは、イオン伝導性が乏しいため、サイクル寿命特性が乏しい。
これに対して、上記硫化物等は、初期の充電過程で、硫化ナトリウム(Na2S)系の固体電解質に分解する。硫化ナトリウム(Na2S)系の固体電解質層は、ナトリウムイオンの吸蔵・放出の過程で、ナトリウムイオンを移動させることができる固体である。
そのため、本発明のナトリウム二次電池用負極材料は、初期の充電過程で、イオン伝導性の良好な硫化ナトリウム(Na2S)系の固体電解質に分解することで、高容量であってもサイクル寿命特性が良好なものとなる。
尚、アンチモンはリチウムイオン二次電池では負極活物質とはならない。本発明者らの実験によれば、図25に示すように、1サイクル目は1000mAh/gを超える容量でリチウムを吸蔵するが、0-1V(vs.Li+/Li)の電圧範囲では負極活物質として機能しない。このことから、負極活物質としてアンチモンを使用することは容易に想起し得ないことであると言える。
アンチモンを10~70モル%とするのは、10モル%未満であると負極容量が小さい電極となるだけでなく、サイクル寿命特性が乏しくなり、70モル%を超えると硫黄の量が少ないため、硫化ナトリウム系の固体電解質の形成量が少なくなり、イオン伝導性が乏しくなることや、充放電に伴う(i)の体積膨張を吸収するバッファー層の量が少なくサイクル寿命特性が悪い電極となり、いずれの場合も好ましくないためであり、20~65モル%とすることがより好ましく、30~60モル%とすることがさらに好ましい。
(i)を3~60モル%とするのは、3モル%未満であると負極容量が少ない電極となり、60モル%を超えると硫黄の量が少ないため、硫化ナトリウム系の固体電解質の形成量が少なくなり、イオン伝導性が乏しくなることや、充放電に伴う(i)の体積膨張を吸収するバッファー層の量が少なくサイクル寿命特性が悪い電極となり、また、アンチモンの量も少なくなるためサイクル寿命特性が悪い電極となり、いずれの場合も好ましくないためであり、20~55モル%とすることがより好ましく、30~50モル%とすることがさらに好ましい。
Geの含有量は0.5~40モル%とすることが好ましく、1~20モル%とすることがより好ましい。
Geの含有量が0.5モル%未満であるとガラス化が充分に行われないおそれがあり、40モル%を超えるとアンチモンの量が少なくなるため、サイクル寿命特性が悪くなることや、(i)の量が少なくなるため、負極容量が小さい電極になる。また、Geは高価な元素であるため、コスト高な電極となり、いずれの場合も好ましくない。
原料としては、硫黄(S)とアンチモン(Sb)の必須成分の他に、必要に応じて任意成分(i)として、Sn、Bi、Ge、Ga、Pb等の単体金属、又はこれらの硫化物、或いはAs、C(ハードカーボン等)などの非金属を使用できる。
硫化物等に導電性金属、炭素等の導電性被覆を形成する方法としては、スパッタリング、蒸着法、メカニカルアロイ(MA)法、ロータリーキルン法、無電解めっき法などの公知の技術を利用できる。
この方法で用いる炭素前駆体は、加熱によって炭化する有機材料であればよく、例えば、粘着性を有するハイドロカーボン系有機物、石炭系ピッチ、石油系ピッチ等を用いることができる。これらの内で、粘着性を有するハイドロカーボン系有機物としては、フェノ-ル樹脂、フラン樹脂、クエン酸、PVA、ウルシオールなどを例示できる。これらの炭素前駆体は一種単独又は二種以上混合して用いることができる。
加熱処理の時間は、炭素前駆体が炭化する時間であれば良く、通常は、1~24時間程度とすればよい。加熱時間が短すぎる場合には、炭素前駆体が充分には炭化されず、電子伝導性の悪い負極になるので好ましくない。一方、加熱時間が長すぎると、熱処理が無駄であり、経済的に好ましくない。
炭化処理時の雰囲気は、不活性雰囲気、還元雰囲気等の非酸化性雰囲気とすればよい。具体的には、He(ヘリウム)、Ne(ネオン)、Ar(アルゴン)、N2(窒素)、H2(水素)等の雰囲気とすればよい。
このような複合粉末からなるナトリウム二次電池用負極材料とすることにより、更なる高容量化が可能となる。
(A)B成分の原料を調合し、熱処理(温度400~1100℃、処理時間1~30時間)により調合物を固溶化させB成分を得る工程
(B)A成分とB成分を複合化させる工程
上記(A)工程と(B)工程のうち、(A)工程としては、例えば上記した硫化物複合体の製造方法を採用することができる。(B)工程としては、メカニカルミリングによりA成分とB成分を複合化させる工程や、溶融したB成分にA成分を分散させ、冷却後、粉砕処理を行う工程などを採用することができる。これら(B)工程については後程詳述する。
例えば、C、Mg、P、Ca、Sc、V、Cr、Mn、Fe、Co、Zn、Ga、Ge、Y、Zr、Nb、Mo、Pd、Ag、Cd、In、Sn、Sb、W、Pb及びBiよりなる群から選択される少なくとも一種以上の元素、これらの元素を用いた合金、酸化物、カルコゲン化物又はハロゲン化物であればよい。
これらのなかでも、放電プラトーの領域が0~1V(vs.Na+/Na)の範囲内に観測できる観点から、C、Mg、Ti、Zn、Ge、Ag、In、Sn及びPbよりなる群から選択される少なくとも一種以上の元素、これらの元素を用いた合金、酸化物、カルコゲン化物又はハロゲン化物が好ましい。
さらにエネルギー密度の観点から、元素としては、Zn、Ge、Ag、Sn、Bi等が好ましく、合金としては、Al-Ge、Si-Ge、Si-Sn、Zn-Sn、Ge-Ag、Ge-Sn、Ge-Sb、Ag-Sn、Ag-Ge、Sn-Sb、Sb-Bi等の各組み合わせ等が好ましく、酸化物としては、SnO、SnO2、SnC2O4、GeO、等が好ましく、カルコゲン化物としては、SnS、SnS2等が好ましく、ハロゲン化物としては、SnF2、SnCl2、SnI2、SnI4等が好ましい。
尚、上記したA成分は一種のみで使用してもよいし二種以上使用してもよい。
本発明のナトリウム二次電池用負極材料は、初期の充電(Na吸蔵)過程で、B成分が、Na還元により、硫化ナトリウム、アンチモン、及びスズに分相する。硫化ナトリウムは、0~1V(vs.Na+/Na)の条件では活物質として関与しないため、以後の充放電反応には関与しない。その他、複合粉末中の骨格として存在し、充放電反応に関与する分相したSb、SnやA成分のイオン伝導性を向上させ、分相したSb、SnやA成分が体積変化をしても、複合粉末全体としての体積変化を効果的に抑制できる。
以上から、上記複合粉末からなる本発明のナトリウム二次電池用負極材料は、分相したSb、SnやA成分のもつ大きな可逆的な電気容量と、固体電化質層兼バッファー層であるNa2S相のもつ不可逆成分の骨格構造をもつことで、高容量、サイクル寿命等に優れた特性を示す。
その理由は、A成分核の周囲にB成分が存在することで、ナトリウムの吸蔵・放出(充電・放電)に伴うA成分のイオン伝導性を向上させることと、膨張・収縮に起因する割れを抑制することができるためである。これにより、A成分のみでは、イオン伝導性やサイクル寿命が乏しい活物質でもイオン伝導性とサイクル特性を向上させることができるので、導電性が乏しい或いは高容量な(体積膨張の大きな)活物質でもサイクル寿命特性が良好なものとなる。
A成分は、一次粒子そのものであってもよいし、凝集した二次粒子等であってもかまわない。B成分は、A成分の全面に完全に被覆されていてもよいし、A成分の一部のみに被覆されていてもよい。A成分の一部のみに被覆されている場合は、A成分の表面積の20%以上がB成分で被覆されていればよい。本発明において、A成分がB成分で被覆されている割合は、例えば、走査型電子顕微鏡(SEM)写真を用いることにより測定することができる。
メカニカルミリング処理とは、衝撃・引張り・摩擦・圧縮・せん断等の外力を原料粉末(少なくともA成分及びB成分)に与える方法であって、転動ミル、振動ミル、遊星ミル、揺動ミル、水平ミル、アトライターミル、ジェットミル、擂潰機、ホモジナイザー、フルイダイザー、ペイントシェイカー、ミキサー等などを用いる方法が挙げられる。
例えば、遊星ミルを用いる方法では、原料粉末とボールとを共に容器に入れ、自転と公転をさせることによって生じる力学的エネルギーにより、原料粉末を粉砕・混合又は固相反応させることができる。この方法によれば、ナノオーダーまで粉砕されることが知られている。
B成分がA成分よりも少ない場合には、上記したメカニカルミリング処理を行う方法ではA成分にB成分が被覆されにくいため、この方法(溶融したB成分にA成分を分散させ、冷却後粉砕する方法)を採用することが好ましい。
B成分を溶融する条件としては、特に限定されないが、加熱温度が400℃未満だと溶融されにくく、1100℃を超える温度ではB成分が分解されるおそれがある。したがって、加熱温度は400~1100℃程度であり、500~900℃がより好ましい。
尚、上記(A)工程において導電助剤をB成分に含有させてもよいし、(A)工程と(B)工程の両方において導電助剤をB成分に含有させてもよい。
B成分を100wt%とした場合、導電助剤は、これに対して0.1~10wt%含有するのが好ましく、0.5~5wt%含有するのがより好ましい。含有量が0.1~10wt%の場合、充分な導電性改善効果が得られ、高率放電特性を向上させることができるとともに、A成分からB成分が脱落することによる容量低下も最低限に抑えることができる。上記導電助剤のなかでも、凝集性の高い導電剤、例えばカーボンブラックを用いた場合には、撹拌機、超音波等で導電助剤を分散させることが好ましい。
上記した複合粉末の他に、上記した硫化物等(例えば硫化アンチモンや硫化物ガラス)、及びこれに導電性を有する被覆を形成した硫化物等も同様に、ナトリウム電池用負極材料として有効に使用できる。
これら本発明の負極材料を用い、集電体上に被着形成することで、ナトリウム二次電池用の負極として良好に機能させることができる。
尚、本発明では負極材料の製造時に、上記(A)工程及び/又は(B)工程において、導電助剤、バインダー等を入れることにより、B成分中に導電助剤、バインダー等を含有させることができるが、この場合であっても、当該負極材料を用いた負極の製造時において、導電助剤、バインダー等をさらに含有させてもよい。例えば、上記負極材料に加えて導電助剤及びバインダー等を含有させた混合物(負極合剤)に、適当な溶剤(N-メチル-2-ピロリドン(NMP)、水、アルコール、キシレン、トルエン等)を加えて充分に混練して得られる負極合剤ペースト組成物、負極合剤スラリー等を、集電体表面に塗布、乾燥し、更にプレスすることで、集電体表面に負極材料含有層を形成し、負極とすることができる。
この負極を搭載したナトリウム二次電池を作製する場合には、公知のナトリウム二次電池の電池要素(正極、セパレーター、電解液等)を用いて、常法に従って、角型、円筒型、コイン型等のナトリウム二次電池に組み立てればよい。
負極の負極材料含有層の厚みは、電極容量密度にもよるが、例えば、0.5~200μmであることが好ましい。負極材料含有層の厚みをこの範囲とすることで、集電体が負極材料を支持しつつ、実用的な電気容量を得ることができる。
集電体の形状には線状、棒状、板状、箔状、網状、織布、不織布、エキスパンド、多孔体又は発泡体があり、このうち充填密度を高めることができること、出力特性が良好なことから、エキスパンド、多孔体又は発泡体が好ましい。
例えば、ポリエチレン(PE)、ポリプロピレン(PP)、ポリエステル、セルロース、ポリアミド等の樹脂からなる多孔質シート、ガラスフィルター、不織布等を用いることができるが、これらに限定はされない。
通常、ECは常温では固体であるため、EC単独では電解液としての機能を果たさない。しかし、PC、DMC、DEC、EMCなどとの混合溶媒とすることで、常温でも使用可能な電解液として機能する。
あるいは、溶媒を用いず、固体電解質でもかまわない。
ナトリウム二次電池の構造としては、特に限定されないが、積層式電池、捲回式電池などの既存の電池形態・構造に適用できる。
上述の構造のナトリウム二次電池によれば、二次電池として機能する。
表1に示す組成からなる9種類の硫化物等1~9を用意した。
硫化物等1は、市販の硫化アンチモン(Sb2S3)(高純度化学社製)を使用した。
硫化物等2~5は、原料を下記表1に示す配合により調合し、調合物を熱処理により溶融させ、硫化物ガラスを作製した。熱処理条件は、調合物を20℃/時間の昇温速度で所定温度まで昇温後、同温度で12時間保持した。その後、室温まで自然冷却して、製造した。得られた硫化物等2~8については、X線回折装置を用いたXRD測定によりガラス化されていることを確認した。尚、硫化物等1および硫化物等9はガラス化されていない。
下記表2に示すA成分及び/又はB成分を出発材料とし、ジルコニア製のボール及び容器にて、遊星型ボールミルを用いて粉砕又はミリング処理(常温、常圧、アルゴンガス雰囲気下)を行った。
実施例1~16、参考例1~3で用いた出発材料、A成分とB成分の調合比、及び合成条件(重力加速度、時間)を表2に示す。
実施例6~11および実施例16は、A成分とB成分とのミリング処理によりA成分の表面にB成分を被覆した複合粉末が得られた。実施例1~5、12~15はB成分のみ、参考例1~3はA成分のみであるため、粉砕処理によりA成分又はB成分のみの粉末が得られた。
実施例1~16、参考例1~3で得られた負極材料を負極活物質として用い、負極活物質80wt%、PIバインダー15wt%、KB5wt%を混合してスラリー状の合剤を調製し、金属箔上に塗布・乾燥後、ロールプレス機により、金属箔と塗膜とを密着接合させ、次いで、加熱処理(減圧下、200℃、1時間以上)して試験電極(負極)を得た。金属箔は、実施例1~5、12~15及び参考例1~3については銅箔(厚さ43μm)、実施例6~11、16についてはアルミニウム箔(厚さ20μm)を用いた。尚、実施例8については、銅箔(厚さ20μm)を用いたものも同条件で作製した。(以下、銅箔を用いたものを実施例8-1、アルミニウム箔を用いたものを実施例8-2と称す)
対極として、金属ナトリウム箔(直径13mm×厚さ0.5mm)を用い、セパレータとしてガラスフィルター(GA100)、電解液としてNaPF6をEC:DMC(1:1vol%)の混合溶媒に溶解させたもの(濃度:1mol/L)を具備した試験セル(コインセル(CR2032))を作製した。
作製した試験セル(ナトリウム二次電池)を0.5C率で充放電試験した。カットオフ電位は0-1V(vs.Na+/Na)に設定した。
実施例1~16および参考例1~3のサイクル寿命を表3にまとめて示す。
実施例1~7のサイクル寿命をそれぞれ図1~図7に示し、実施例2~5のサイクル寿命をまとめて図8に示し、実施例3,6,7及び参考例1のサイクル寿命をまとめて図9に示す。実施例8-1,8-2,9,10及び11のサイクル寿命をそれぞれ図10~図13に示し、実施例1,8-1及び参考例2のサイクル寿命をまとめて図14に示す。
また、実施例1~7の充放電曲線を図15~図21にそれぞれ示し、実施例8-1,8-2,9の充放電曲線を図22~図24にそれぞれ示す。
(1)実施例1は、容量は約200mAh/gと低いが、サイクル寿命特性は安定しており、Sn単独(参考例1)やSb単独(参考例3)と比較してサイクル寿命特性は良好である。(図1,図9,図15、表3参照)
(2)実施例2は、Sn単独(参考例1)やSb単独(参考例3)と比較してサイクル寿命特性は良好であるが、40サイクル以降から容量の低下がみられる。(図2,図9,図15、表3参照)
(3)実施例3は、実施例1,2に比べてサイクル寿命特性が良好である。これはGeを含有することによるものと考えられる。(図3,図8,図17参照)
(4)実施例4は、実施例1,2に比べてサイクル寿命特性が良好であり、実施例3のSb量を増加してもサイクル寿命特性が良好であることが分かる。(図4,図8,図18参照)
(5)実施例5は、サイクルを経るにつれて活物質容量が増加している。(図5,図8,図19参照)
(6)実施例2~5のサイクル寿命特性は、実施例2<実施例5<実施例4<実施例3の順に良好である。(図8参照)
(7)実施例6は、実施例3に比べて活物質容量が増加している。これにより、硫化物等とSnとを複合化することにより活物質容量が増加することが分かる。(図6,図20参照)
(8)実施例7は、実施例6に比べて10サイクルまで活物質容量が大きい(500~600mAh/g)が、サイクル寿命特性は悪くなった。このことから、硫化物等に複合化するSnの量が過剰になると、サイクル寿命特性が悪化することが分かる。(図7,図9,図21参照)
(9)実施例8-1は、300mAh/g以上の高い活物質容量を長いサイクルに亘って安定して維持している。このことから、原料としてガラス化していない硫化物等1(Sb2S3)を使用しても、当該硫化物等を他の原料(Sn)と複合化することにより、活物質容量及びサイクル寿命特性が大幅に向上することが分かる。(図10,図14,図22参照)
(10)実施例8-2は、実施例8-1の電極劣化を抑制する目的で集電体をアルミニウムとしたものであるが、300mAh/g以上の高い活物質容量を長いサイクルに亘って安定して維持しており、150サイクルの充放電を繰り返しても劣化は小さく、集電体の劣化は見られなかった。(図11,図23参照)
(11)実施例9は、実施例8に比べて不可逆容量が減少している。これはSn量を増やしたことによるものと考えられる。また、Sn量を増やすことにより、多段階プラトーが顕著になった。(図12,図24参照)
(12)実施例10,11は、それぞれ容量は約200mAh/g、約250mAh/gと低いが、サイクル寿命特性は安定しており、Sn単独(参考例1)と比較してサイクル寿命特性は良好である。(図13参照)
本発明のナトリウム二次電池用負極を用いた二次電池は、高エネルギー密度であり、サイクル寿命特性が良好であるため、電動工具、自動車等の電源として使用ができるだけでなく、電気機器、電気製品、または、乗り物等の用途での使用が可能となる。また、バックアップ用の電源としても使用可能である。
電気機器、電気製品、または、乗り物には、例えば、エアコン、洗濯機、テレビ、冷蔵庫、冷凍庫、冷房機器、ノートパソコン、パソコンキーボード、パソコン用ディスプレイ、デスクトップ型パソコン、ノート型パソコン、CRTモニター、パソコンラック、プリンター、一体型パソコン、マウス、ハードディスク、パソコン周辺機器、アイロン、衣類乾燥機、ウインドウファン、トランシーバー、送風機、換気扇、テレビ、音楽レコーダー、音楽プレーヤー、オーブン、レンジ、洗浄機能付便座、温風ヒーター、カーコンポ、カーナビ、懐中電灯、加湿器、携帯カラオケ機、換気扇、乾燥機、乾電池、空気清浄器、携帯電話、非常用電灯、ゲーム機、血圧計、コーヒーミル、コーヒーメーカー、こたつ、コピー機、ディスクチェンジャー、ラジオ、シェーバー、ジューサー、シュレッダー、浄水器、照明器具、除湿器、食器乾燥機、炊飯器、ステレオ、ストーブ、スピーカー、ズボンプレッサー、掃除機、体脂肪計、体重計、ヘルスメーター、ムービープレーヤー、電気カーペット、電気釜、炊飯器、電気かみそり、電気スタンド、電気ポット、電子ゲーム機、携帯ゲーム機、電子辞書、電子手帳、電子レンジ、電磁調理器、電卓、電動カート、電動車椅子、電動工具、電動歯ブラシ、あんか、散髪器具、電話機、時計、インターホン、エアサーキュレーター、電撃殺虫器、複写機、ホットプレート、トースター、ドライヤー、電動ドリル、給湯器、パネルヒーター、粉砕機、はんだごて、ミシン、ビデオカメラ、ビデオデッキ、ファクシミリ、ファンヒーター、フードプロセッサー、布団乾燥機、ヘッドホン、電気ポット、ホットカーペット、マイク、マッサージ機、豆電球、ミキサー、ミシン、もちつき機、床暖房パネル、ランタン、リモコン、冷温庫、冷水器、冷凍ストッカー、冷風器、ワープロ、泡だて器、電子楽器、オートバイ、おもちゃ類、芝刈り機、電気うき、自転車、自動車、ハイブリッド自動車、電気自動車、鉄道、船、飛行機、非常用蓄電池などが挙げられる。
Claims (15)
- 硫黄と、アンチモンと、を含む硫化物又は硫化物複合体からなるナトリウム二次電池用負極材料。
- 更に、下記(i)の成分を含み、
(i)Sn、As、Bi、Ge、Ga、Pb、Cからなる群から選択される少なくとも一種以上の元素、
硫黄、アンチモン、上記成分(i)の割合が、硫黄:10~70モル%、アンチモン:10~70モル%、(i):3~60モル%である請求項1記載のナトリウム二次電池用負極材料。 - 上記硫化物複合体が、硫化物ガラスからなり、Geの成分を0.5~40モル%含む請求項2に記載のナトリウム二次電池用負極材料。
- (1)A成分が、ナトリウムを電気化学的に吸蔵及び放出することができる材料、
(2)B成分が、請求項1~3のいずれかに記載の硫化物又は硫化物複合体、
からなるA成分とB成分の複合粉末であるナトリウム二次電池用負極材料。 - 上記複合粉末が、A成分表面にB成分が被覆された複合粉末である請求項4に記載のナトリウム二次電池用負極材料。
- 上記複合粉末全体におけるA成分とB成分の割合が、両者の合計量を100mass%とした場合に、A成分が40~95mass%であり、B成分が60~5mass%である請求項4又は5に記載のナトリウム二次電池用負極材料。
- 請求項1~6いずれかに記載の負極材料を用いたナトリウム二次電池用の負極。
- 水系バインダーを含有する請求項7に記載のナトリウム二次電池用の負極。
- ポリイミドバインダーを含有する請求項7に記載のナトリウム二次電池用の負極。
- 請求項7~9いずれかに記載の負極を用いたナトリウム二次電池。
- 電解液が、エチレンカーボネートからなる主溶媒と、プロピレンカーボネート、エチルメチルカーボネート、ジメチルカーボネート及びジエチルカーボネートから選択される一種以上からなる副溶媒とからなる混合溶媒に、NaPF6を溶解させたものである請求項10に記載のナトリウム二次電池。
- 請求項4記載のナトリウム二次電池用負極材料の製造方法であって、
(A)B成分の原料を調合し、熱処理(温度400~1100℃、処理時間1~30時間)により調合物を固溶化させB成分を得る工程、
(B)A成分とB成分を複合化させる工程、
を備えるナトリウム二次電池用負極材料の製造方法。 - 上記工程(B)が、メカニカルミリングによりA成分とB成分を複合化させる工程である請求項12記載のナトリウム二次電池用負極材料の製造方法。
- 上記工程(B)が、溶融したB成分に、A成分を分散させ、冷却後、粉砕処理を行う工程である請求項12記載のナトリウム二次電池用負極材料の製造方法。
- 上記(A)及び/又は(B)の工程で、導電助剤及び/又はバインダーを入れ、複合粉末に導電助剤及び/又はバインダーを含有させる請求項12記載のナトリウム二次電池用負極材料の製造方法。
Priority Applications (5)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
KR1020147013830A KR101649427B1 (ko) | 2011-11-02 | 2012-11-01 | 나트륨 2차 전지용 음극 재료 및 이의 제조 방법, 및 나트륨 2차 전지용 음극 및 나트륨 2차 전지 |
US14/355,252 US9553308B2 (en) | 2011-11-02 | 2012-11-01 | Negative electrode material for sodium secondary battery and method for producing same, negative electrode for sodium secondary batter, and sodium secondary battery |
JP2013541837A JP6119021B2 (ja) | 2011-11-02 | 2012-11-01 | ナトリウム二次電池用負極材料及びその製造方法、並びにナトリウム二次電池用負極及びナトリウム二次電池 |
CN201280053204.0A CN103999272B (zh) | 2011-11-02 | 2012-11-01 | 钠二次电池用负极材料及其制造方法,以及钠二次电池用负极及钠二次电池 |
EP12845609.2A EP2782169B1 (en) | 2011-11-02 | 2012-11-01 | Negative electrode material for sodium secondary battery and method for producing same, negative electrode for sodium secondary battery, and sodium secondary battery |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2011-241539 | 2011-11-02 | ||
JP2011241539 | 2011-11-02 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2013065787A1 true WO2013065787A1 (ja) | 2013-05-10 |
Family
ID=48192125
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/JP2012/078329 WO2013065787A1 (ja) | 2011-11-02 | 2012-11-01 | ナトリウム二次電池用負極材料及びその製造方法、並びにナトリウム二次電池用負極及びナトリウム二次電池 |
Country Status (6)
Country | Link |
---|---|
US (1) | US9553308B2 (ja) |
EP (1) | EP2782169B1 (ja) |
JP (1) | JP6119021B2 (ja) |
KR (1) | KR101649427B1 (ja) |
CN (1) | CN103999272B (ja) |
WO (1) | WO2013065787A1 (ja) |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2013211170A (ja) * | 2012-03-30 | 2013-10-10 | Kyocera Corp | 蓄電デバイス |
WO2015087734A1 (ja) * | 2013-12-09 | 2015-06-18 | 日本電気硝子株式会社 | ナトリウムイオン電池用電極合材、及びその製造方法並びにナトリウム全固体電池 |
CN105514392A (zh) * | 2016-01-25 | 2016-04-20 | 陕西科技大学 | 一种SnS2-SnO2纳米片状钠离子电池负极复合材料及其制备方法 |
JP2016522557A (ja) * | 2013-06-17 | 2016-07-28 | サントレ ナティオナル ド ラ ルシェルシェ シアンティフィク | ナトリウムイオン電池の負極活物質としての新規の化合物の使用 |
CN114927690A (zh) * | 2022-05-06 | 2022-08-19 | 益阳生力材料科技股份有限公司 | 一种氮掺杂碳包覆纳米锑铋合金材料及其制备方法和应用 |
Families Citing this family (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP5002824B1 (ja) * | 2011-03-02 | 2012-08-15 | 独立行政法人産業技術総合研究所 | リチウム二次電池用負極材料及びその製造方法、並びにリチウム二次電池用負極及びリチウム二次電池 |
US9431655B2 (en) | 2012-03-28 | 2016-08-30 | Sharp Laboratories Of America, Inc. | Antiomony and layered carbon network battery anode |
JP6114971B2 (ja) * | 2013-04-10 | 2017-04-19 | 国立研究開発法人産業技術総合研究所 | リチウム二次電池用負極活物質及びその製造方法 |
WO2015161400A1 (zh) * | 2014-04-21 | 2015-10-29 | 厦门大学 | 硫基过渡金属复合型负极活性物质及相应负极及相应电池 |
KR102437075B1 (ko) * | 2014-12-01 | 2022-08-30 | 한국전기연구원 | 나트륨 2차 전지용 전해액 |
KR101948217B1 (ko) * | 2016-07-26 | 2019-02-14 | 한국과학기술연구원 | 이차전지용 음극 소재, 이를 포함하는 이차전지 및 이의 제조방법 |
TWI654269B (zh) * | 2017-12-19 | 2019-03-21 | 財團法人工業技術研究院 | 黏著組合物 |
KR102198713B1 (ko) * | 2019-01-16 | 2021-01-05 | 금오공과대학교 산학협력단 | 니오븀-안티몬 금속간 화합물 (Nb5Sb4) 제조 방법, 이에 의해 제조된 화합물을 포함하는 이차전지용 전극 물질, 이를 포함하는 리튬 또는 나트륨 이차전지 |
CN111204731B (zh) * | 2020-01-07 | 2022-05-27 | 大连理工大学 | 一种钠离子电池硬炭负极材料的制备方法 |
Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5873968A (ja) | 1981-08-13 | 1983-05-04 | モ−リ・エネルギ−・リミテツド | 電極ユニット |
JPH03155062A (ja) | 1989-11-14 | 1991-07-03 | Showa Denko Kk | 二次電池 |
JP2006244976A (ja) | 2005-02-07 | 2006-09-14 | Sanyo Electric Co Ltd | 負極およびそれを用いた非水電解質二次電池 |
JP2008004461A (ja) * | 2006-06-26 | 2008-01-10 | Sanyo Electric Co Ltd | 非水電解質二次電池 |
WO2010109889A1 (ja) | 2009-03-27 | 2010-09-30 | 学校法人東京理科大学 | ナトリウムイオン二次電池 |
JP2011134551A (ja) * | 2009-12-24 | 2011-07-07 | Sumitomo Chemical Co Ltd | 電極活物質、電極およびナトリウム二次電池 |
Family Cites Families (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2003059492A (ja) * | 2001-08-17 | 2003-02-28 | Matsushita Electric Ind Co Ltd | リチウム二次電池およびその製造方法 |
JP4997674B2 (ja) * | 2001-09-03 | 2012-08-08 | 日本電気株式会社 | 二次電池用負極および二次電池 |
US6991662B2 (en) * | 2001-09-10 | 2006-01-31 | Polyplus Battery Company | Encapsulated alloy electrodes |
JP4055642B2 (ja) | 2003-05-01 | 2008-03-05 | 日産自動車株式会社 | 高速充放電用電極および電池 |
JP4264567B2 (ja) * | 2004-11-05 | 2009-05-20 | ソニー株式会社 | 二次電池 |
JP4989183B2 (ja) | 2006-10-20 | 2012-08-01 | 出光興産株式会社 | 極材及びそれを用いた固体二次電池 |
JP5448020B2 (ja) * | 2007-03-23 | 2014-03-19 | トヨタ自動車株式会社 | 合材層の製造方法および固体電池の製造方法 |
JP5696353B2 (ja) * | 2009-07-22 | 2015-04-08 | トヨタ自動車株式会社 | 全固体電池システム |
JP5707698B2 (ja) | 2009-12-24 | 2015-04-30 | 住友化学株式会社 | 電極の製造方法、電極ペーストの製造方法およびナトリウム二次電池 |
JP5355493B2 (ja) | 2010-05-14 | 2013-11-27 | カヤバ工業株式会社 | ハイブリッド建設機械 |
-
2012
- 2012-11-01 EP EP12845609.2A patent/EP2782169B1/en active Active
- 2012-11-01 WO PCT/JP2012/078329 patent/WO2013065787A1/ja active Application Filing
- 2012-11-01 CN CN201280053204.0A patent/CN103999272B/zh active Active
- 2012-11-01 JP JP2013541837A patent/JP6119021B2/ja active Active
- 2012-11-01 US US14/355,252 patent/US9553308B2/en active Active
- 2012-11-01 KR KR1020147013830A patent/KR101649427B1/ko active IP Right Grant
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5873968A (ja) | 1981-08-13 | 1983-05-04 | モ−リ・エネルギ−・リミテツド | 電極ユニット |
JPH03155062A (ja) | 1989-11-14 | 1991-07-03 | Showa Denko Kk | 二次電池 |
JP2006244976A (ja) | 2005-02-07 | 2006-09-14 | Sanyo Electric Co Ltd | 負極およびそれを用いた非水電解質二次電池 |
JP2008004461A (ja) * | 2006-06-26 | 2008-01-10 | Sanyo Electric Co Ltd | 非水電解質二次電池 |
WO2010109889A1 (ja) | 2009-03-27 | 2010-09-30 | 学校法人東京理科大学 | ナトリウムイオン二次電池 |
JP2011134551A (ja) * | 2009-12-24 | 2011-07-07 | Sumitomo Chemical Co Ltd | 電極活物質、電極およびナトリウム二次電池 |
Non-Patent Citations (5)
Title |
---|
PREMKUMAR SENGUTTUVAN ET AL.: "Na2Ti307:Lowest Voltage Ever Reported Oxide Insertion Electrode for Sodium Ion Batteries", CHEMISTRY OF MATERIALS, vol. 23, 30 August 2011 (2011-08-30), pages 4109 - 4111, XP055067229 * |
RIKI KATAOKA ET AL.: "Development of high capacity positive electrode material for sodium ion battery", PACIFIC RIM MEETING ON ELECTROCHEMICAL AND SOLID-STATE SCIENCE 2012 (PRIME 2012), 7 October 2012 (2012-10-07), XP055153907 * |
TAKASHI MUKAI ET AL.: "3D32 Sodium Ion Denchi-yo Sn-Sb-kei Ryukabutsu Fukyoku no Kenkyu Kaihatsu", ABSTRACTS OF THE 79TH ANNUAL MEETING OF THE ELECTROCHEMICAL SOCIETY OF JAPAN, 29 March 2012 (2012-03-29), pages 138, XP008173419 * |
TAKASHI MUKAI ET AL.: "lC04 Sn-Sb-kei Iou Glass Fukyoku o Mochiita Li Ion Niji Denchi Tokusei", THE 52ND BATTERY SYMPOSIUM IN JAPAN KOEN YOSHISHU, 17 October 2011 (2011-10-17), pages 181, XP008173420 * |
WATARU MURATA ET AL.: "hard carbon for sodium ion battery", 50TH BATTERY DEBATE, vol. 1 D05, 30 November 2009 (2009-11-30), pages 233 |
Cited By (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2013211170A (ja) * | 2012-03-30 | 2013-10-10 | Kyocera Corp | 蓄電デバイス |
JP2016522557A (ja) * | 2013-06-17 | 2016-07-28 | サントレ ナティオナル ド ラ ルシェルシェ シアンティフィク | ナトリウムイオン電池の負極活物質としての新規の化合物の使用 |
JP7015634B2 (ja) | 2013-06-17 | 2022-02-03 | サントレ ナティオナル ド ラ ルシェルシェ シアンティフィク | ナトリウムイオン電池の負極活物質としての新規の化合物の使用 |
WO2015087734A1 (ja) * | 2013-12-09 | 2015-06-18 | 日本電気硝子株式会社 | ナトリウムイオン電池用電極合材、及びその製造方法並びにナトリウム全固体電池 |
JP2016042453A (ja) * | 2013-12-09 | 2016-03-31 | 日本電気硝子株式会社 | ナトリウムイオン電池用電極合材、及びその製造方法並びにナトリウム全固体電池 |
US10020508B2 (en) | 2013-12-09 | 2018-07-10 | Nippon Electric Glass Co., Ltd. | Composite material as electrode for sodium ion batteries, production method therefor, and all-solid-state sodium battery |
CN105514392A (zh) * | 2016-01-25 | 2016-04-20 | 陕西科技大学 | 一种SnS2-SnO2纳米片状钠离子电池负极复合材料及其制备方法 |
CN105514392B (zh) * | 2016-01-25 | 2017-10-13 | 陕西科技大学 | 一种SnS2‑SnO2纳米片状钠离子电池负极复合材料及其制备方法 |
CN114927690A (zh) * | 2022-05-06 | 2022-08-19 | 益阳生力材料科技股份有限公司 | 一种氮掺杂碳包覆纳米锑铋合金材料及其制备方法和应用 |
CN114927690B (zh) * | 2022-05-06 | 2023-08-29 | 益阳生力材料科技股份有限公司 | 一种氮掺杂碳包覆纳米锑铋合金材料及其制备方法和应用 |
Also Published As
Publication number | Publication date |
---|---|
EP2782169A4 (en) | 2015-11-04 |
KR101649427B1 (ko) | 2016-08-18 |
JP6119021B2 (ja) | 2017-04-26 |
CN103999272B (zh) | 2017-03-15 |
US9553308B2 (en) | 2017-01-24 |
JPWO2013065787A1 (ja) | 2015-04-02 |
CN103999272A (zh) | 2014-08-20 |
EP2782169B1 (en) | 2020-02-19 |
EP2782169A1 (en) | 2014-09-24 |
KR20140092365A (ko) | 2014-07-23 |
US20150280220A1 (en) | 2015-10-01 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
JP6119021B2 (ja) | ナトリウム二次電池用負極材料及びその製造方法、並びにナトリウム二次電池用負極及びナトリウム二次電池 | |
JP5002824B1 (ja) | リチウム二次電池用負極材料及びその製造方法、並びにリチウム二次電池用負極及びリチウム二次電池 | |
JP5812482B2 (ja) | ナトリウム二次電池、ナトリウム二次電池用負極の製造方法および電気機器 | |
EP3667783B1 (en) | Lithium-ion battery electrode material, lithium-ion capacitor electrode material, electrode, battery, capacitor, electric device, production method for lithium-ion battery electrode material, and production method for lithium-ion capacitor electrode material | |
JP6474548B2 (ja) | 非水電解質二次電池用負極材及び負極活物質粒子の製造方法 | |
JP3262704B2 (ja) | 非水系二次電池用炭素電極、その製造方法及びそれを用いた非水系二次電池 | |
JP6445956B2 (ja) | 負極活物質、混合負極活物質材料、非水電解質二次電池用負極、リチウムイオン二次電池 | |
WO2017085911A1 (ja) | 負極活物質、混合負極活物質材料、非水電解質二次電池用負極、リチウムイオン二次電池、負極活物質の製造方法、及びリチウムイオン二次電池の製造方法 | |
JP2013197069A (ja) | リチウム二次電池用負極材料及びその製造方法、リチウム二次電池用負極及びその製造方法、リチウム二次電池及びこれを用いた電気機器 | |
JP5660539B2 (ja) | リチウムイオン二次電池用電極、リチウムイオン二次電池、および電気機器 | |
JP2013171798A (ja) | ナトリウム二次電池用負極材料及びその製造方法、並びにナトリウム二次電池用負極、ナトリウム二次電池及びこれを用いた電気機器 | |
JP2016143642A (ja) | 非水電解質二次電池 | |
JP2013196978A (ja) | ナトリウム二次電池用正極材料及びその製造方法、並びにナトリウム二次電池用正極、ナトリウム二次電池及びこれを用いた電気機器 | |
JP5709126B2 (ja) | リチウム二次電池用負極材料及びその製造方法 | |
JP6115909B2 (ja) | リチウム二次電池用負極およびその製造方法、並びに該負極を用いたリチウム二次電池および該電池を用いた電気機器 | |
JP5999683B2 (ja) | 高温特性に優れたリチウムイオン二次電池用正極、この正極を具備するリチウムイオン二次電池及びこの二次電池を用いた電気機器 | |
WO2023120724A1 (ja) | リン-炭素複合材料、リン-炭素複合材料の製造方法、負極活物質、リチウム二次電池用負極及びリチウム二次電池 |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 12845609 Country of ref document: EP Kind code of ref document: A1 |
|
DPE1 | Request for preliminary examination filed after expiration of 19th month from priority date (pct application filed from 20040101) | ||
ENP | Entry into the national phase |
Ref document number: 2013541837 Country of ref document: JP Kind code of ref document: A |
|
WWE | Wipo information: entry into national phase |
Ref document number: 14355252 Country of ref document: US |
|
NENP | Non-entry into the national phase |
Ref country code: DE |
|
ENP | Entry into the national phase |
Ref document number: 20147013830 Country of ref document: KR Kind code of ref document: A |
|
WWE | Wipo information: entry into national phase |
Ref document number: 2012845609 Country of ref document: EP |