WO2011049158A1 - Negative electrode active material for electricity storage device, and method for producing same - Google Patents
Negative electrode active material for electricity storage device, and method for producing same Download PDFInfo
- Publication number
- WO2011049158A1 WO2011049158A1 PCT/JP2010/068551 JP2010068551W WO2011049158A1 WO 2011049158 A1 WO2011049158 A1 WO 2011049158A1 JP 2010068551 W JP2010068551 W JP 2010068551W WO 2011049158 A1 WO2011049158 A1 WO 2011049158A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- negative electrode
- electrode active
- active material
- storage device
- electricity storage
- 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
- H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
- H01M4/139—Processes of manufacture
- H01M4/1395—Processes of manufacture of electrodes based on metals, Si or alloys
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/05—Accumulators with non-aqueous electrolyte
- H01M10/052—Li-accumulators
- H01M10/0525—Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
- H01M4/139—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
- H01M4/48—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides
- H01M4/485—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of mixed oxides or hydroxides for inserting or intercalating light metals, e.g. LiTi2O4 or LiTi2OxFy
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M2004/021—Physical characteristics, e.g. porosity, surface area
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/10—Energy storage using batteries
Definitions
- the present invention relates to a negative electrode active material used for an electricity storage device such as a non-aqueous secondary battery represented by a lithium ion secondary battery used in a portable electronic device or an electric vehicle, and a method for producing the same.
- LiCoO 2 LiCo 1-x Ni x O 2 , LiNiO 2 , LiMn 2 O 4 and the like are widely used as positive electrode materials for lithium ion secondary batteries.
- a carbonaceous material is generally used as the negative electrode material. These materials function as electrode active materials that reversibly occlude and release lithium ions by charging and discharging, and constitute so-called rocking chair type secondary batteries that are electrochemically connected by a non-aqueous electrolyte or a solid electrolyte. .
- Carbonaceous materials used as active materials (negative electrode active materials) that can occlude or release lithium ions in the negative electrode include graphitic carbon materials, pitch coke, fibrous carbon, and high-capacity soft carbon that is fired at low temperatures. There is. However, since the carbon material has a relatively small lithium insertion capacity, there is a problem that the battery capacity is low. Specifically, even if a stoichiometric amount of lithium insertion capacity can be realized, the battery capacity of the carbon material is limited to about 372 mAh / g.
- a negative electrode active material containing SnO has been proposed as a negative electrode active material capable of inserting and extracting lithium ions and having a high capacity density exceeding that of a carbon-based material (see, for example, Patent Document 1). .
- the negative electrode active material proposed in Patent Document 1 cannot relieve the volume change due to the insertion and extraction reactions of Li ions during charge and discharge, and the structure deterioration of the negative electrode active material is significantly cracked when repeatedly charged and discharged. Is likely to occur. As cracks progress, in some cases, cavities are formed in the negative electrode active material and may be pulverized. When a crack occurs in the negative electrode active material, the electron conduction path is interrupted, so that a reduction in discharge capacity (charge / discharge cycle characteristics) after repeated charge / discharge has been a problem.
- a negative electrode active material composed of an oxide mainly composed of tin oxide and a method for producing the negative electrode active material by a melting method have been proposed (for example, see Patent Document 2).
- a manufacturing method by a sol-gel method has been proposed as a method for manufacturing a negative electrode active material made of an oxide containing tin oxide and silicon and having a large specific surface area (see, for example, Patent Document 3).
- the negative electrode active material manufactured by these manufacturing methods has a low ratio of the discharge capacity to the initial charge capacity (initial charge / discharge efficiency), and a decrease in the discharge capacity (cycle characteristics) after repeated charge / discharge is a problem. It was.
- a negative electrode active material for a non-aqueous secondary battery that can relieve the volume change associated with insertion and extraction of lithium ions and has an excellent charge / discharge cycle has been proposed.
- these negative electrode active materials contain a considerable amount of oxides other than tin oxide, which are not related to occlusion and release of lithium ions, so as to be amorphous oxides. For this reason, there is a problem that the tin oxide content per unit mass of the negative electrode active material is small and it is difficult to further increase the capacity.
- a first problem of the present invention is to provide a negative electrode active material for an electricity storage device that can be further increased in capacity as compared with a conventional negative electrode active material and is excellent in charge / discharge cycle characteristics and safety. .
- a second problem of the present invention is to provide a negative electrode active material for an electricity storage device that is excellent in initial charge / discharge efficiency and cycle characteristics.
- a third problem of the present invention is to provide a negative electrode active material for an electricity storage device that is excellent in cycle characteristics as compared with a conventional negative electrode active material.
- the present inventors have found that the first problem can be solved by using a negative electrode active material for an electricity storage device containing a high proportion of tin oxide in the composition, and proposed as the present invention.
- the “electric storage device” includes a non-aqueous secondary battery, in particular, a lithium-ion non-aqueous secondary battery used in portable electronic devices such as notebook computers and mobile phones, electric vehicles, and the like. Hybrid capacitors such as ion capacitors are included.
- the present invention contains a composition of SnO 70 to 95% and P 2 O 5 5 to 30% (not including SnO 70 mol% and P 2 O 5 30 mol%) in terms of mol% in terms of oxide.
- the present invention relates to a negative electrode active material for an electricity storage device.
- the negative electrode active material for an electricity storage device of the present invention contains SnO at a high ratio of 70 to 95% (not including 70 mol%), the content of tin oxide per unit mass of the negative electrode active material is large, and the further high Capacitance can be achieved.
- SnO ingredient content in the present invention the tin oxide component other than SnO (SnO 2, etc.) also refers to that summed in terms of SnO.
- the negative electrode active material is preferably substantially amorphous.
- substantially amorphous means that the degree of crystallinity is substantially 0%, which is a 2 ⁇ value obtained by powder X-ray diffraction measurement using CuK ⁇ rays, and is 10 to 60.
- the present invention also relates to a method for producing the above-described negative electrode active material for an electricity storage device, wherein the raw material powder is melted and vitrified in a reducing atmosphere or an inert atmosphere.
- a lithium ion secondary battery undergoes the following reaction at the negative electrode during charging and discharging.
- the first charge / discharge efficiency is excellent.
- the smaller the valence of Sn x + ions (reduced state) the fewer electrons required for the reduction, which is advantageous for improving the initial charge / discharge efficiency of the secondary battery. Therefore, by melting the raw material powder in a reducing atmosphere or an inert atmosphere and vitrifying it, Sn x + ions can be effectively reduced to reduce the valence, and a secondary battery with excellent initial charge efficiency can be obtained. Can be obtained.
- the raw material powder used in the above production method is preferably a composite oxide containing phosphorus and tin.
- a negative electrode active material excellent in homogeneity can be easily obtained.
- the non-aqueous secondary battery with stable discharge capacity is obtained by using the negative electrode material containing the said negative electrode active material as a negative electrode.
- the present inventors have used negative electrode active materials containing at least SnO and P 2 O 5, which are used for power storage devices such as non-aqueous secondary batteries, and used CuK ⁇ rays.
- the diffraction line profile obtained by powder X-ray diffraction (powder XRD) measurement by controlling the halo pattern (amorphous halo) due to a broad amorphous component detected at 2 ⁇ value of 10 to 45 °, the first The present inventors have found that the second problem can be solved and propose the present invention.
- the present invention is a negative electrode active material for an electricity storage device containing at least SnO and P 2 O 5, and has a 2 ⁇ value of 10 to 45 ° in a diffraction line profile obtained by powder X-ray diffraction measurement using CuK ⁇ rays.
- the curve fitting is performed with two components of a peak component P1 having an amorphous halo and a 2 ⁇ value fixed at 22.5 ° in the range and a peak component P2 higher than 22.5 °, P2
- the position of the peak apex is 25.0 to 29.0 ° in terms of 2 ⁇ value.
- the present inventors pay attention to the valence of Sn x + (0 ⁇ x ⁇ 4) ions in the negative electrode active material for power storage devices and the inclusion state of Sn x + ions in the phosphate network, and control the initial values by appropriately controlling them. It has been found that an electricity storage device having excellent discharge efficiency and cycle characteristics can be obtained. Specifically, in the diffraction line profile obtained by powder X-ray diffraction measurement, the peak component P1 in which the 2 ⁇ value is fixed at 22.5 ° for the amorphous halo having a 2 ⁇ value of 10 to 45 ° is the phosphate network.
- a lithium ion secondary battery undergoes the following reaction at the negative electrode during charging and discharging.
- the valence x is Sn x + ion. It exists in a continuously changing state. For this reason, the diffraction line profile obtained by the powder X-ray diffraction measurement becomes a broad scattering band, and the 2 ⁇ value at the peak apex of the peak component P2 detected on the higher angle side than 22.5 ° is the average of the Sn x + ions. Reflects the valence. Therefore, by restricting the position of the peak apex of P2 within the above range, it is possible to obtain a secondary battery with excellent initial charge / discharge efficiency.
- Li y Sn alloy formation from Sn x + ions occurs during the initial charge
- the negative electrode active material occludes y lithium ions released from the positive electrode material and causes volume expansion.
- This volume change can be estimated from the viewpoint of crystal structure.
- SnO crystal because the length of the crystal unit cell is tetragonal in 3.802 ⁇ ⁇ 3.802 ⁇ ⁇ 4.836 ⁇ , crystal unit volume becomes 69.9 ⁇ 3. Since Sn atoms are present twice in the crystal unit cell, the occupied volume per Sn1 atoms becomes 34.95 ⁇ 3.
- Li 2.6 Sn, Li 3.5 Sn, Li 4.4 Sn, and the like are known as Li y Sn alloys formed during charging.
- the length of the unit cell of Li 4.4 Sn (cubic system, space group F23) is 19.78 ⁇ ⁇ 19.78 ⁇ ⁇ 19. because it is 78A, the lattice unit volume becomes 7739 ⁇ 3. Since Sn atoms are present 80 to the unit cell volume occupied per Sn1 atoms becomes 96.7 ⁇ 3. For this reason, when SnO crystal is used for the negative electrode material, the occupied volume of Sn atoms expands 2.77 times (96.7 ⁇ 3 /34.95 ⁇ 3 ) at the first charge.
- the reaction formula (2) proceeds leftward, and y ions are released from the Li y Sn alloy to form metal Sn, so that the negative electrode active material shrinks in volume.
- the shrinkage rate in this case is obtained from the crystallographic viewpoint as described above.
- Length of the unit lattice of the metal Sn is tetragonal in 5.831 ⁇ ⁇ 5.831 ⁇ ⁇ 3.182 ⁇ , unit cell volume becomes 108.2 ⁇ 3. Since Sn atoms are present four in this lattice, the volume occupied per Sn1 atoms becomes 27.05 ⁇ 3. Therefore, when the Li y Sn alloy is Li 4.4 Sn, when the discharge reaction in the negative electrode active material proceeds and metal Sn is generated, the occupied volume of Sn atoms is 0.28 times (27.5%) 3 / 96.7 ⁇ 3 ).
- reaction formula (2) proceeds to the right, the metal Sn occludes y Li ions and electrons, and an Li y Sn alloy is formed. Volume expansion. At this time, when Li 4.4 Sn is formed from the metal Sn, the occupied volume of Sn atoms expands to 3.52 times (96.7 / 3 /27.5 ⁇ 3 ).
- the negative electrode active material containing SnO is remarkably accompanied by a volume change during charging and discharging, the negative electrode active material is likely to crack when repeatedly charged and discharged. As cracks progress, in some cases, cavities are formed in the negative electrode active material and may be pulverized. When a crack occurs in the negative electrode active material, the electron conduction network is divided, so that the charge / discharge capacity is likely to be reduced, which causes a reduction in cycle characteristics.
- Sn x + ions in the negative electrode active material exist in a state where they are included in the phosphate network, so that the volume change of Sn atoms associated with charge and discharge can be mitigated by the phosphate network.
- the 2 ⁇ value at the peak apex of the peak component P2 is only the average valence of the Sn x + ion. It is also considered that the inclusion state of the phosphate network to Sn x + ions is also reflected.
- the present invention is a negative electrode active material for an electricity storage device containing at least SnO and P 2 O 5, and has a 2 ⁇ value of 10 to 45 ° in a diffraction line profile obtained by powder X-ray diffraction measurement using CuK ⁇ rays.
- the curve fitting is performed with two components of a peak component P1 having an amorphous halo and a 2 ⁇ value fixed at 22.5 ° in the range and a peak component P2 higher than 22.5 °, P1
- the peak component P1 can be attributed to a component of the phosphate network, and the peak component P2 can be attributed to a component derived from tin. Therefore, by limiting the peak area ratio A1 / A2 regarding these peak components to the above range, the inclusion state of the phosphate network to Sn x + ions can be controlled, and the volume change of Sn atoms accompanying charge / discharge Can be effectively mitigated. As a result, it is possible to obtain a power storage device such as a secondary battery having excellent cycle characteristics when repeatedly charged and discharged.
- the negative electrode active material of the present invention preferably contains, in mol%, a composition of SnO 45 to 95% and P 2 O 5 5 to 55%.
- the negative electrode active material of the present invention is preferably substantially amorphous.
- substantially amorphous means that no crystalline diffraction line is detected in powder X-ray diffraction measurement using CuK ⁇ rays, and the crystallinity is substantially 0%, specifically Indicates that the crystallinity is 0.1% or less.
- the present invention is a method for producing the negative electrode active material for an electricity storage device described above, wherein the raw material powder is melted and vitrified in a reducing atmosphere or an inert atmosphere.
- the raw material powder used in the above production method is preferably a composite oxide containing phosphorus and tin.
- a negative electrode active material excellent in homogeneity can be easily obtained. Furthermore, by using a negative electrode material containing the negative electrode active material as a negative electrode, an electricity storage device having a stable discharge capacity can be obtained.
- the present invention is a negative electrode active material used for an electricity storage device composed of at least a negative electrode and a positive electrode, and has a 2 ⁇ value of 30 to 30 of a diffraction line profile obtained by powder X-ray diffraction measurement using CuK ⁇ rays when charging is completed.
- a half-value width of a diffraction line peak detected in a range of 50 ° and / or a range of 2 ⁇ value of 10 to 30 ° is 0.5 ° or more.
- the present invention also relates to a negative electrode active material used in an electricity storage device comprising at least a negative electrode and a positive electrode, and at the time of completion of discharge, a 2 ⁇ value of a diffraction line profile obtained by powder X-ray diffraction measurement using CuK ⁇ rays is 15 to 15
- the half width of the diffraction line peak detected in the range of 40 ° is 0.1 ° or more.
- a lithium ion secondary battery undergoes the following reaction at a negative electrode containing Sn during charging and discharging.
- the metal Sn combines with Li ions that have moved from the positive electrode through the electrolyte and electrons supplied from the circuit to form a reaction that forms a Sn—Li alloy (Li y Sn) (formula (1)). ).
- the length of the unit lattice of the metal Sn is tetragonal in 5.831 ⁇ ⁇ 5.831 ⁇ ⁇ 3.182 ⁇ , unit cell volume becomes 108.2 ⁇ 3. Since Sn atoms are present four in this lattice, the volume occupied per Sn1 atoms becomes 27.05 ⁇ 3.
- Li 2.6 Sn, Li 3.5 Sn, Li 4.4 Sn, and the like are known as Li y Sn alloys formed during charging.
- the length of the unit cell of Li 4.4 Sn (cubic system, space group F23) is 19.7823 ⁇ 19.78 ⁇ ⁇ 19.
- the lattice unit volume is 7739 cm 3 . Since Sn atoms are present 80 to the unit cell volume occupied per Sn1 atoms becomes 96.7 ⁇ 3. Therefore, the occupied volume of Sn atoms expands 3.52 times (96.796 3 /27.05 ⁇ 3 ) during charging.
- the reaction formula (1) proceeds leftward, and y ions are released from the Li y Sn alloy to form metal Sn, so that the negative electrode active material shrinks in volume.
- the occupied volume of Sn atoms contracts by 0.28 times (27.5 ⁇ 3 /96.7 ⁇ 3 ).
- the negative electrode active material containing metal Sn is accompanied by a significant volume change during charge and discharge, as described above, the negative electrode active material is likely to crack when repeatedly charged and discharged, resulting in cycle characteristics. Causes a drop.
- the present inventors have a structure in which Sn—Li alloy fine particles and Sn fine particles serving as Li ion storage / release sites are nano-sized (approximately 0.1 to 100 nm) and uniformly dispersed in the negative electrode active material, It has been found that a secondary battery having excellent cycle characteristics can be obtained because the volume change of the active material associated with the charge / discharge reaction can be reduced.
- the negative electrode active material has a specific diffraction line profile, the crystallite size of Sn—Li alloy fine particles and Sn fine particles Is nano-sized, and it has been clarified that these fine particles are uniformly present in a matrix such as a network-forming oxide.
- the negative electrode active material at the completion of charging is detected in the 2 ⁇ value range of 30-50 ° or the 2 ⁇ value range of 10-30 ° of the diffraction line profile obtained by powder X-ray diffraction measurement using CuK ⁇ rays.
- the diffraction line peak detected in the 2 ⁇ value range of 15 to 40 ° of the diffraction line profile obtained by the powder X-ray diffraction measurement using CuK ⁇ ray is the metal crystal phase of the metal Sn. It was found that if the half width of the diffraction line peak is 0.1 ° or more, the crystallite size of the metal crystal is a nano-sized fine particle. And by restricting each half-value width to the above range, it is possible to absorb and relax the volume change of Sn atoms associated with charge / discharge, and as a result, a secondary battery excellent in cycle characteristics when repeatedly charged / discharged. Can be obtained.
- the negative electrode active material for an electricity storage device of the present invention represents SnO 10 to 70%, Li 2 O 20 to 70%, P 2 O 5 2 to 40% in terms of mol% in terms of oxide. It is preferable to contain.
- SnO SnO 2, metal Sn, etc.
- the present inventors have determined that the second problem is that in the negative electrode active material for an electricity storage device containing tin oxide, the binding energy of electrons of Sn atoms in the negative electrode material is controlled. It is found that the problem can be solved and is proposed as the present invention.
- the present invention is a negative electrode active material for an electricity storage device containing at least SnO as a composition, wherein the binding energy value of electrons in the Sn3d 5/2 orbit of Sn atoms in the negative electrode material for the electricity storage device is represented by Pl, metal Sn (Pl-Pm) is 0.01 to 3.5 eV, where Pm is the electron binding energy value in the Sn3d 5/2 orbital.
- a lithium ion secondary battery undergoes the following reaction at the negative electrode during charge and discharge.
- the present inventors introduced the binding energy value Pl of electrons in the Sn3d 5/2 orbit of the Sn atom as an index indicating the valence state of Sn x + ion in the negative electrode. Then, by regulating the difference (Pl ⁇ Pm) between the bond energy value Pl and the electron bond energy value Pm in the Sn3d 5/2 orbit of metal Sn to 3.5 eV or less, it is possible to store electricity with excellent initial charge / discharge efficiency. I found that the device was obtained.
- the binding energy value of electrons in the Sn3d 5/2 orbit of the Sn atom is the binding energy value of the point where the maximum detected intensity was obtained in the X-ray electron spectroscopy spectrum of the Sn3d 5/2 orbit using MgK ⁇ ray.
- the negative electrode active material for an electricity storage device of the present invention is preferably substantially amorphous.
- substantially amorphous means that the crystallinity is substantially 0%. Specifically, in powder X-ray diffraction measurement using CuK ⁇ rays. Means that no crystalline diffraction line is detected.
- the negative electrode active material for an electricity storage device of the present invention is preferably in a powder form.
- the specific surface area can be increased to increase the capacity.
- the negative electrode active material for an electricity storage device of the present invention preferably has an average particle size of 0.1 to 10 ⁇ m and a maximum particle size of 75 ⁇ m or less.
- the present invention is also a method for producing the negative electrode active material for an electricity storage device, wherein the raw material powder is melted and vitrified in a reducing atmosphere or an inert atmosphere.
- the raw material powder used in the production method of the present invention preferably contains a metal powder or a carbon powder.
- the Sn component in the negative electrode active material can be reduced, and the valence of Sn ions can be reduced. Therefore, an electrical storage device having excellent initial charge / discharge efficiency can be obtained for the reasons already described.
- the raw material powder used in the production method of the present invention is preferably a composite oxide containing phosphorus and tin.
- Using a composite oxide containing phosphorus and tin as the starting material powder makes it easier to obtain a negative electrode material with excellent homogeneity.
- the negative electrode material containing the negative electrode active material as a negative electrode, an electricity storage device having a stable discharge capacity can be obtained.
- FIG. 4 It is a figure which shows the powder X-ray-diffraction line profile of the negative electrode material of Example 4 of Table 2. It is the figure which showed the base line at the time of subtracting a background by linear fitting with respect to the powder X-ray-diffraction line profile of the negative electrode material of Example 4 of Table 2.
- FIG. It is the figure which carried out curve fitting of the diffraction line profile which subtracted the background about the negative electrode material of Example 4 of Table 2 by peak component P1 and P2. It is the figure which showed the profile obtained by subtracting a background from the diffraction-line profile at the time of charging to 0V about the negative electrode active material of Example 2 of Table 5.
- FIG. It is a figure which shows the 3d 5/2 orbital XPS spectrum of Sn atom of the negative electrode material of Example 5 of Table 7, and the 3d 5/2 orbital XPS spectrum of metal Sn.
- the negative electrode active material for an electricity storage device includes SnO 70 to 95%, P 2 O 5 5 to 30% (SnO 70%, P 2 O 5 30%) in terms of mol%. Not included). The reason for limiting the composition in this way will be described below. In the following description, “%” means “mol%” unless otherwise specified.
- SnO is an active material component that becomes a site for occluding and releasing lithium ions in the negative electrode active material.
- the SnO content is preferably 70 to 95% (not including 70%), 70.1 to 87%, 70.5 to 82%, particularly 71 to 77%.
- the discharge capacity per unit mass of the negative electrode active material becomes small.
- the charging / discharging efficiency at the time of first charge / discharge becomes small.
- the content of SnO is more than 95%, the amorphous component in the negative electrode active material is reduced, and the volume change due to insertion and extraction of lithium ions during charging and discharging cannot be sufficiently relaxed, and charging and discharging are repeated. There is a risk of rapid capacity loss.
- P 2 O 5 is a matrix component that includes SnO that serves as a site for occlusion and release of lithium ions, and the effect of alleviating volume changes associated with SnO occlusion and release of lithium ions to improve charge / discharge cycle characteristics.
- P 2 O 5 is a network-forming oxide and functions as a solid electrolyte to which lithium ions can move.
- the content of P 2 O 5 is preferably 5 to 30% (not including 30%), 5 to 29.2%, and particularly preferably 8 to 29.5%. When the content of P 2 O 5 is less than 5%, the volume change associated with insertion and extraction of lithium ions during charge / discharge cannot be alleviated and structural deterioration is likely to occur.
- the cycle performance is very poor and there is a risk of causing a rapid capacity drop.
- the discharge capacity per unit mass of the negative electrode active material tends to decrease.
- the water resistance is likely to deteriorate, and when exposed to high temperature and high humidity for a long time, undesired foreign crystals (for example, SnHPO 4 etc.) are formed, or moisture is easily impregnated or adsorbed in the negative electrode active material.
- water is decomposed inside the non-aqueous secondary battery, and it is inferior in safety because it causes explosion due to release of oxygen and heat generation due to reaction between lithium and water.
- the total amount of SnO and P 2 O 5 is preferably 80% or more, 85% or more, and particularly preferably 87% or more. If the total amount of SnO and P 2 O 5 is less than 80%, it becomes difficult to achieve both cycle characteristics and high capacity.
- the molar ratio of SnO to P 2 O 5 is preferably 2.3 to 19, 2.3 to 18, and particularly preferably 2.4 to 17.
- SnO / P 2 O 5 is smaller than 2.3, the Sn atom in SnO tends to be affected by the coordination of P 2 O 5 , and the valence of the Sn atom tends to increase. As a result, the initial charge efficiency Tends to decrease.
- SnO / P 2 O 5 is greater than 19, the reduction in discharge capacity during repeated charge / discharge tends to increase. This is because the amount of P 2 O 5 coordinated with SnO in the negative electrode active material is reduced and the P 2 O 5 component cannot contain SnO. As a result, the volume change of SnO associated with insertion and extraction of lithium ions is mitigated. This is considered to be because it becomes impossible to cause structural deterioration.
- various components can be added in addition to the above components within the range not impairing the effects of the present invention.
- examples of such components include CuO, ZnO, B 2 O 3 , MgO, CaO, Al 2 O 3 , SiO 2 , R 2 O (R represents Li, Na, K, or Cs).
- the total content of the above components is preferably 0 to 20%, 0 to 15%, particularly preferably 0.1 to 13%.
- the negative electrode active material for an electricity storage device preferably has a crystallinity of 95% or less, 80% or less, 70% or less, 50% or less, particularly 30% or less, most preferably substantially It is preferably amorphous (the crystallinity is substantially 0%).
- the crystallinity is substantially 0%.
- the degree of crystallinity of the negative electrode active material is a 2 ⁇ value obtained by powder X-ray diffraction measurement using CuK ⁇ rays, and is obtained by separating peaks into crystalline diffraction lines and amorphous halos in a diffraction line profile of 10 to 60 °. Desired. Specifically, the integrated intensity obtained by peak-separating a broad diffraction line (amorphous halo) at 10 to 40 ° from the total scattering curve obtained by subtracting the background from the diffraction line profile is Ia, 10 to When the sum of integrated intensities obtained by peak-separating each crystalline diffraction line detected at 60 ° is Ic, the degree of crystallinity Xc is obtained from the following equation.
- the negative electrode active material according to the first embodiment may contain a phase composed of a complex oxide of metal and oxide, or an alloy phase of metal and metal.
- the negative electrode material is lithium oxide, Sn—Li alloy or metal. May contain tin.
- the negative electrode active material according to the first embodiment is manufactured, for example, by heating and melting raw material powder to vitrify it.
- An oxide containing Sn is likely to change the oxidation state of Sn atoms depending on the melting condition, and the bond energy of electrons is likely to change.
- the change in the oxidation state of Sn atoms can be suppressed as described above, and a secondary battery excellent in initial charge / discharge efficiency can be obtained.
- a reducing gas In order to melt in a reducing atmosphere, it is preferable to supply a reducing gas into the melting tank.
- a reducing gas As the reducing gas, it is preferable to use a mixed gas of N 2 90 to 99.5%, H 2 0.5 to 10%, particularly N 2 92 to 99%, H 2 1 to 8% by volume%. .
- an inert gas When melting in an inert atmosphere, it is preferable to supply an inert gas into the melting tank.
- the inert gas it is preferable to use any of nitrogen, argon, and helium.
- a composite oxide containing phosphorus and tin as a starting material powder.
- a composite oxide containing phosphorus and tin for the starting raw material powder, a negative electrode active material with few devitrified foreign substances and excellent uniformity is easily obtained.
- the negative electrode material containing the negative electrode active material as a negative electrode, a nonaqueous secondary battery with a stable discharge capacity can be obtained.
- the composite oxide containing phosphorus and tin include stannous pyrophosphate (Sn 2 P 2 O 7 ).
- the negative electrode active material for an electricity storage device contains at least SnO and P 2 O 5 and has a 2 ⁇ value of 10 in a diffraction line profile obtained by powder X-ray diffraction measurement using CuK ⁇ rays.
- a peak component P1 having an amorphous halo at 45 ° and a 2 ⁇ value fixed at 22.5 ° in this range, and a peak component P2 at a higher angle than 22.5 °.
- the peak apex position of P2 is 25.0 to 29.0 ° in terms of 2 ⁇ .
- the Sn ion in the negative electrode active material is strongly influenced by the coordination due to the lone pair of oxygen atoms present in the phosphate network. Will do.
- the initial charge / discharge efficiency is significantly reduced because the electrons required to reduce Sn atoms in the negative electrode active material to metal Sn and the lithium ions required for charge compensation are excessively required during the initial charge.
- the peak position of the peak component P2 is larger than 29.0 °, it means that the tin oxide in the negative electrode active material is not sufficiently included in the phosphate network and mainly exists in the SnO molecular group.
- Preferable ranges of the peak position of the peak component P2 are 25.1 to 28.8 °, 25.3 to 28.5 °, 25.5 to 28.3 °, and further 25.7 to 28.0 °. Note that the peak position of the peak component P2 can be regulated within the above range by appropriately adjusting the ratio of SnO to P 2 O 5 in the negative electrode active material and the melting atmosphere.
- the negative electrode active material for an electricity storage device contains at least SnO and P 2 O 5 and is obtained by powder X-ray diffraction measurement using CuK ⁇ rays.
- the 2 ⁇ value has an amorphous halo at 10 to 45 °
- the peak area ratio A1 / A2 is larger than 8, Sn ions in the negative electrode active material exist in a state in which they are strongly influenced by coordination by the lone electron pairs of oxygen atoms in the phosphate network. For this reason, the electrons required to reduce Sn atoms in the negative electrode active material to metal Sn at the time of the first charge, and further lithium ions required for charge compensation are required, and the initial charge / discharge efficiency is significantly reduced.
- Preferable ranges of the peak area ratio A1 / A2 are 0.02 to 7.5, 0.1 to 6.5, 0.2 to 5.5, and further 0.3 to 4.5.
- the peak area ratio A1 / A2 can be regulated within the above range by appropriately adjusting the ratio of SnO to P 2 O 5 in the negative electrode active material and the melting atmosphere.
- the negative electrode active material for an electricity storage device contains at least SnO and P 2 O 5 as a composition.
- SnO is an active material component that becomes a site for inserting and extracting lithium ions in the negative electrode material.
- the SnO content is preferably 45 to 95%, 50 to 90%, particularly 55 to 85% in terms of mol%.
- the capacity per unit mass of the negative electrode active material becomes small.
- the amorphous component in the negative electrode active material decreases, so that the volume change associated with insertion and extraction of lithium ions during charge and discharge cannot be mitigated, and rapid discharge capacity is reduced. There is a risk of lowering.
- SnO ingredient content in the present invention, the tin oxide component other than SnO (SnO 2, etc.) also refers to that summed in terms of SnO.
- P 2 O 5 is a network-forming oxide, covers the lithium ion storage and release sites of SnO, and functions as a solid electrolyte to which lithium ions can move.
- the content of P 2 O 5 is preferably 5 to 55%, 10 to 50%, particularly 15 to 45% in terms of mol%. If the content of P 2 O 5 is less than 5%, the volume change of SnO associated with the insertion and extraction of lithium ions during charge / discharge cannot be alleviated, resulting in structural deterioration. Therefore, the discharge capacity during repeated charge / discharge decreases. Easy to grow.
- the molar ratio of SnO to P 2 O 5 is preferably 0.8 to 19, 1 to 18, and particularly preferably 1.2 to 17.
- SnO / P 2 O 5 is smaller than 0.8, the Sn atom in SnO is easily affected by the coordination of P 2 O 5 , and the peak position of the peak component P2 is shifted to the low angle side, so that the first charge / discharge is performed. Efficiency tends to decrease.
- SnO / P 2 O 5 is greater than 19, the discharge capacity tends to decrease when charging and discharging are repeated. This is because the amount of P 2 O 5 coordinated with SnO in the negative electrode active material is reduced and P 2 O 5 cannot sufficiently contain SnO. As a result, the volume change of SnO due to insertion and extraction of lithium ions is reduced. This is thought to be due to the fact that the structure cannot be relaxed and structural deterioration occurs.
- various components can be further added to the negative electrode active material according to the second embodiment.
- CuO, ZnO, B 2 O 3 , MgO, CaO, Al 2 O 3 , SiO 2 , R 2 O (R represents Li, Na, K or Cs) in a total amount of 0 to 20%, 0 to It can be contained in an amount of 10%, especially 0-7%. If it exceeds 20%, vitrification tends to occur, but the phosphate network tends to be cut. As a result, the discharge capacity tends to decrease when the battery is repeatedly charged and discharged. Moreover, since A1 decreases and the peak area ratio A1 / A2 decreases, the cycle characteristics deteriorate.
- the negative electrode active material according to the second embodiment is made of, for example, amorphous and / or crystalline material containing a plurality of oxide components as a composition.
- the negative electrode active material preferably has a crystallinity of 95% or less, 80% or less, 70% or less, 50% or less, particularly 30%, and most preferably substantially amorphous.
- the degree of crystallinity the larger the proportion of the amorphous phase
- the volume change during repeated charge / discharge can be reduced, which is advantageous from the viewpoint of suppressing the reduction in discharge capacity. .
- the degree of crystallinity of the negative electrode active material is determined by separating the peak into a crystalline diffraction line and an amorphous halo in a diffraction line profile of 10-60 ° with a 2 ⁇ value obtained by powder X-ray diffraction measurement using CuK ⁇ rays. Desired.
- the integrated intensity obtained by peak-separating a broad diffraction line (amorphous halo) at 10 to 45 ° from the total scattering curve obtained by subtracting the background from the diffraction line profile is Ia, 10
- the degree of crystallinity Xc can be obtained from the following equation.
- the negative electrode active material according to the second embodiment may contain a phase composed of a complex oxide of metal and oxide or an alloy phase of metal and metal.
- the negative electrode material is lithium oxide, Sn—Li alloy or metal. May contain tin.
- the negative electrode active material according to the second embodiment is manufactured, for example, by heating and melting raw material powder to vitrify it.
- An oxide containing Sn is likely to change the oxidation state of Sn atoms depending on the melting conditions. When it is melted in the atmosphere, unwanted SnO 2 crystals are formed on the melt surface or in the melt, resulting in the initial charge / discharge efficiency. Lowers the cycle characteristics and deteriorates the cycle characteristics.
- an increase in the valence of Sn ions in the negative electrode active material can be suppressed by melting in a reducing atmosphere or an inert atmosphere. As a result, it is possible to suppress the formation of undesired crystals such as SnO 2 and SnP 2 O 7 and to obtain a power storage device such as a secondary battery excellent in initial charge / discharge efficiency and cycle characteristics.
- a reducing gas In order to melt in a reducing atmosphere, it is preferable to supply a reducing gas into the melting tank.
- a mixed gas containing 90% to 99.5% N 2 , 0.5% to 10% H 2 , particularly 92% to 99% N 2 , and 1% to 8% H 2 is used. preferable.
- an inert gas When melting in an inert atmosphere, it is preferable to supply an inert gas into the melting tank.
- the inert gas it is preferable to use any of nitrogen, argon, and helium.
- the reducing gas or the inert gas may be supplied to the upper atmosphere of the molten glass in the melting tank, may be supplied directly from the bubbling nozzle into the molten glass, or both methods may be performed simultaneously.
- the melting temperature is preferably 500 ° C to 1300 ° C.
- the melting temperature is higher than 1300 ° C.
- isolated phosphoric acid and tin oxide form crystals, or SnO components not included in the phosphoric acid network tend to decompose into metallic Sn and SnO 2 crystals, leading to a decrease in initial charge / discharge efficiency and cycle characteristics. is there.
- the melting temperature is lower than 500 ° C., it is difficult to obtain a homogeneous amorphous material.
- a composite oxide containing phosphorus and tin as the starting material powder.
- a composite oxide containing phosphorus and tin for the starting raw material powder, a negative electrode active material with few devitrified foreign substances and excellent uniformity is easily obtained.
- the negative electrode material containing the negative electrode active material as a negative electrode, an electricity storage device having a stable discharge capacity can be obtained.
- the composite oxide containing phosphorus and tin include stannous pyrophosphate (Sn 2 P 2 O 7 ).
- the negative electrode active material for an electricity storage device has a 2 ⁇ value in the range of 30 to 50 ° of the diffraction line profile obtained by powder X-ray diffraction measurement using CuK ⁇ rays at the completion of charging, and / or Alternatively, the half width of the diffraction line peak detected in the range of 2 ⁇ value of 10 to 30 ° is 0.5 ° or more, 0.6 ° or more, 0.7 ° or more, 0.8 ° or more, 0.9 It is preferably at least 1 °, particularly at least 1 °.
- the crystallite size of the Li y Sn alloy crystal in the negative electrode active material is large, indicating that submicron (approximately 100 nm or more) particles are formed. ing. For this reason, when Li ions are released due to a discharge reaction, a large volume shrinkage occurs locally in the negative electrode active material, and the negative electrode active material itself is easily cracked. Micronization and peeling from the electrode occur, and as a result, the cycle characteristics tend to deteriorate.
- the upper limit of the half width of the diffraction line peak is not particularly limited, but in reality, it is 15 ° or less, 14 ° or less, 13.5 ° or less, 13 ° or less, 12.5 ° or less, particularly 12 ° or less. Preferably there is.
- the half width of the diffraction line peak is larger than 15 °, it means that the amount of Li y Sn alloy crystal formed in the negative electrode active material is small, and as a result, the capacity tends to be small.
- the negative electrode active material according to the third embodiment has a diffraction line detected in the range of 2 ⁇ value of 15 to 40 ° of the diffraction line profile obtained by powder X-ray diffraction measurement using CuK ⁇ ray at the completion of discharge.
- the half width of the peak is 0.1 ° or more, preferably 0.12 ° or more, 0.15 ° or more, 0.2 ° or more, 0.3 ° or more, and particularly preferably 0.5 ° or more.
- the half width of the diffraction line peak is larger than 0.1 °, it indicates that the crystallite size of the metal Sn crystal in the negative electrode active material is a particle of submicron.
- the upper limit of the half-value width of the diffraction line peak is not particularly limited, but in reality, it is preferably 15 ° or less, 14 ° or less, 13 ° or less, 12.5 ° or less, 12 ° or less, particularly 11 ° or less. .
- the half width of the diffraction line peak is greater than 15 °, it indicates that the amount of metal Sn formed in the negative electrode active material is small, and as a result, the capacity tends to be small.
- the negative electrode active material for an electricity storage device is composed of SnO 10 to 70% Li 2 O 20 to 70% P 2 O 5 2 to 40 in terms of oxide in terms of mol% at the completion of discharge. % Is preferably contained. The reason why the content of each component is defined in this way will be described below.
- SnO is an active material component that becomes a site for occluding and releasing Li ions in the negative electrode active material.
- the SnO content is preferably 10 to 70%, 12 to 68%, 14 to 66%, particularly 16 to 64%.
- the content of SnO is less than 10%, the capacity per unit mass of the negative electrode active material becomes small.
- the content of SnO is more than 70%, the amorphous component in the negative electrode active material is reduced, so that the volume change associated with insertion and extraction of Li ions during charge / discharge cannot be reduced, and the discharge capacity rapidly increases. May decrease.
- Li 2 O has a role of improving Li ion conductivity of the negative electrode active material.
- the Li 2 O content is preferably 20 to 70%, 22 to 68%, 24% to 66%, particularly preferably 25% to 65%. If the content of Li 2 O is less than 20%, the Li ion conductivity may decrease and the discharge capacity may decrease. When the content of Li 2 O is more than 70%, the size of the Sn—Li alloy or Sn metal particles increases, and the cycle characteristics may be deteriorated.
- P 2 O 5 is a network-forming oxide, covers the sites for insertion and extraction of Li ions of the SnO component, and functions as a solid electrolyte to which Li ions can move.
- the content of P 2 O 5 is preferably 2 to 40%, 3 to 38%, 4 to 36%, particularly preferably 5 to 35%. If the content of P 2 O 5 is less than 2%, the volume change of the SnO component accompanying the storage and release of Li ions during charge / discharge cannot be alleviated, resulting in structural deterioration. Therefore, the discharge capacity decreases during repeated charge / discharge. It becomes easy. When the content of P 2 O 5 is more than 40%, the discharge capacity per unit mass of the negative electrode active material tends to decrease.
- the water resistance is likely to deteriorate, and when exposed to high temperature and high humidity for a long time, undesired foreign crystals (for example, SnHPO 4 etc.) are formed, or moisture is easily impregnated or adsorbed in the negative electrode active material.
- undesired foreign crystals for example, SnHPO 4 etc.
- moisture is easily impregnated or adsorbed in the negative electrode active material.
- water is decomposed inside the electricity storage device, and it is inferior in safety because it causes explosion due to release of oxygen and heat generation due to reaction between lithium and water.
- the negative electrode active material for an electricity storage device is made of a material containing at least SnO and P 2 O 5 as a composition before the first charge (when the battery is incorporated).
- the content of these components is adjusted in the range of, for example, SnO 45 to 95% and P 2 O 5 5 to 55%.
- SnO is an active material component that becomes a site for occluding and releasing Li ions in the negative electrode active material.
- the SnO content is preferably 45 to 95%, 50 to 90%, particularly 55 to 85% in terms of mol%.
- the capacity per unit mass of the negative electrode active material becomes small. If the content of SnO is more than 95%, the amorphous component in the negative electrode active material decreases, so that the volume change associated with insertion and extraction of Li ions during charge and discharge cannot be mitigated, and rapid discharge capacity is reduced. There is a risk of lowering.
- P 2 O 5 is a network-forming oxide, covers the storage and release sites of SnO Li ions, and functions as a solid electrolyte to which Li ions can move.
- the content of P 2 O 5 is preferably 5 to 55%, 10 to 50%, particularly 15 to 45% in terms of mol%. If the content of P 2 O 5 is less than 5%, the volume change of SnO associated with insertion and extraction of Li ions during charge / discharge cannot be alleviated, resulting in structural deterioration. Therefore, the discharge capacity during repeated charge / discharge decreases. Easy to grow.
- the molar ratio of SnO to P 2 O 5 (SnO / P 2 O 5 ) in the negative electrode active material is preferably 0.8 to 19, 1 to 18, particularly 1.2 to 17.
- SnO / P 2 O 5 is smaller than 0.8, the Sn atom in SnO tends to be affected by the coordination of P 2 O 5 , and the initial charge / discharge efficiency tends to decrease.
- SnO / P 2 O 5 is greater than 19, the discharge capacity tends to decrease when charging and discharging are repeated. This is because the amount of P 2 O 5 coordinated with SnO in the negative electrode active material is reduced and P 2 O 5 cannot sufficiently contain SnO.
- the volume change of SnO due to insertion and extraction of Li ions is reduced. This is thought to be due to the fact that the structure cannot be relaxed and structural deterioration occurs.
- a various component can be further added to the negative electrode active material (at the time of incorporating in an electrical storage device) which concerns on 3rd Embodiment.
- CuO, ZnO, B 2 O 3 , MgO, CaO, Al 2 O 3 , SiO 2 , R 2 O (R represents Li, Na, K or Cs) in a total amount of 0 to 20%, 0 to It is preferable to contain 10%, particularly 0 to 7%. If it exceeds 20%, vitrification tends to occur, but the phosphate network tends to be cut. As a result, the cycle characteristics deteriorate.
- the negative electrode active material for an electricity storage device is produced, for example, by heating and melting raw material powder at 500 to 1300 ° C. to vitrify it.
- An oxide containing Sn is likely to change the oxidation state of Sn atoms depending on the melting conditions. When it is melted in the atmosphere, unwanted SnO 2 crystals are formed on the melt surface or in the melt, resulting in the initial charge / discharge efficiency. Lowers the cycle characteristics and deteriorates the cycle characteristics.
- an increase in the valence of Sn ions in the negative electrode active material can be suppressed by melting in a reducing atmosphere or an inert atmosphere. As a result, it is possible to suppress the formation of unwanted crystals such as SnO 2 and SnP 2 O 7 and to obtain a secondary battery excellent in initial charge / discharge efficiency and cycle characteristics.
- a composite oxide containing phosphorus and tin as the starting material powder.
- a composite oxide containing phosphorus and tin as the starting raw material powder, it is easy to obtain a negative electrode active material with few devitrified foreign substances and excellent uniformity.
- the negative electrode material containing the negative electrode active material for the electrode an electricity storage device having a stable discharge capacity can be obtained.
- the composite oxide containing phosphorus and tin include stannous pyrophosphate (Sn 2 P 2 O 7 ).
- the negative electrode of an electricity storage device such as a non-aqueous secondary battery is formed using a negative electrode material containing the negative electrode active material of the embodiment described above.
- the negative electrode material is obtained by adding a binder such as a thermosetting resin or a conductive auxiliary agent such as acetylene black, ketjen black, highly conductive carbon black, or graphite to the negative electrode active material. .
- the fourth negative active material for a power storage device the electron binding energy value Pl in Sn3d 5/2 orbit of Sn atom of the negative electrode active material in, in Sn3d 5/2 orbital of the metal Sn
- the difference (Pl ⁇ Pm) in the electron binding energy value Pm is 0.01 to 3.5 eV.
- (Pl-Pm) is smaller than 0.01 eV, it means that Sn atoms hardly form bonds with other atoms and exist in a structure close to metal Sn.
- the Sn component tends to exist in the negative electrode active material as an aggregate.
- (Pl-Pm) exceeds 3.5 eV, the electrons required to reduce Sn atoms in the negative electrode material to metal Sn at the time of the first charge, and excessive lithium ions as charge compensation are required. Therefore, the initial charge / discharge efficiency is significantly reduced.
- a preferable range of the bond energy difference (Pl-Pm) is 0.05 to 3.4 eV, 0.1 to 3.35 eV, and further 0.12 to 3.3 eV.
- the negative electrode active material for an electricity storage device contains SnO as at least a composition.
- SnO is an active material component that serves as a site for occluding and releasing lithium ions in the negative electrode active material.
- the SnO content is preferably 45 to 95%, 50 to 90%, particularly 55 to 85% in terms of mol%.
- the capacity per unit mass of the negative electrode active material becomes small.
- the amorphous component in the negative electrode active material decreases, so that the volume change associated with insertion and extraction of lithium ions during charge and discharge cannot be mitigated, and rapid discharge capacity is reduced. There is a risk of lowering.
- Examples of the component constituting the negative electrode active material include P 2 O 5 in addition to SnO.
- P 2 O 5 is a network-forming oxide, covers the lithium ion storage and release sites of SnO, and functions as a solid electrolyte to which lithium ions can move.
- the content of P 2 O 5 is preferably 5 to 55%, 10 to 50%, particularly 15 to 45% in terms of mol%. If the content of P 2 O 5 is less than 5%, the volume change of SnO associated with the insertion and extraction of lithium ions during charge / discharge cannot be alleviated, resulting in structural deterioration. Therefore, the discharge capacity during repeated charge / discharge decreases. Easy to grow.
- the molar ratio of SnO to P 2 O 5 is preferably 0.8 to 19, 1 to 18, and particularly preferably 1.2 to 17.
- SnO / P 2 O 5 is smaller than 0.8, the Sn atom in SnO is easily affected by the coordination of P 2 O 5 , and the bonding between the core electron of the 3d 5/2 orbit of the Sn atom and the nucleus Since the energy becomes stronger, the value of the binding energy Pl increases. As a result, the binding energy difference (Pl-Pm) increases, and the initial charge efficiency tends to decrease.
- SnO / P 2 O 5 is greater than 19, the reduction in discharge capacity during repeated charge / discharge tends to increase.
- various components can be added.
- CuO, ZnO, B 2 O 3 , MgO, CaO, Al 2 O 3 , SiO 2 , R 2 O (R represents Li, Na, K, or Cs) can be contained.
- R represents Li, Na, K, or Cs
- the negative electrode active material for an electricity storage device is made of, for example, an amorphous material and / or a crystalline material containing a plurality of oxide components as a composition.
- This negative electrode active material preferably has a crystallinity of 95% or less, 80% or less, 70% or less, 50% or less, particularly 30%, most preferably substantially amorphous.
- the degree of crystallinity the larger the proportion of the amorphous phase
- the volume change during repeated charge / discharge can be reduced, which is advantageous from the viewpoint of suppressing the reduction in discharge capacity. .
- the degree of crystallinity of the negative electrode active material is a 2 ⁇ value obtained by powder X-ray diffraction measurement using CuK ⁇ rays, and is obtained by separating peaks into crystalline diffraction lines and amorphous halos in a diffraction line profile of 10 to 60 °. Desired. Specifically, the integrated intensity obtained by peak-separating a broad diffraction line (amorphous halo) at 10 to 40 ° from the total scattering curve obtained by subtracting the background from the diffraction line profile is Ia, 10 to When the sum of integrated intensities obtained by peak-separating each crystalline diffraction line detected at 60 ° is Ic, the degree of crystallinity Xc is obtained from the following equation.
- the negative electrode active material according to the fourth embodiment may contain a phase composed of a composite oxide of metal and oxide or an alloy phase of metal and metal.
- the negative electrode active material may contain lithium oxide, Sn—Li alloy, or metallic tin.
- Examples of the form of the negative electrode active material according to the fourth embodiment include a powder form and a bulk form, and are not particularly limited. However, if the form is a powder form, the specific surface area can be increased to increase the capacity. Therefore, it is advantageous.
- the average particle size of the powder is 0.1 to 10 ⁇ m and the maximum particle size is 75 ⁇ m or less, the average particle size is 0.3 to 9 ⁇ m and the maximum particle size is 65 ⁇ m or less, the average particle size is 0.5 to 8 ⁇ m, and the maximum particle size is 55 ⁇ m.
- the average particle size is preferably 1 to 5 ⁇ m and the maximum particle size is 45 ⁇ m or less.
- the capacity tends to be significantly reduced.
- the average particle diameter of the powder is smaller than 0.1 ⁇ m, the powder is in a poorly dispersed state when formed into a paste, and it tends to be difficult to produce a uniform electrode.
- the average particle diameter and the maximum particle diameter are values measured by a laser diffraction particle size distribution measuring apparatus, which indicate D50 (50% volume cumulative diameter) and D100 (100% volume cumulative diameter) as median diameters of primary particles, respectively.
- the specific surface area by the BET method of the powder is preferably a 0.1 ⁇ 20m 2 /g,0.15 ⁇ 15m 2 / g , particularly 0.2 ⁇ 10m 2 / g.
- the specific surface area of the powder is smaller than 0.1 m 2 / g, the insertion and extraction of Li ions cannot be performed quickly, and the charge / discharge time tends to be long.
- the specific surface area of the powder is larger than 20 m 2 / g, the powder tends to be charged with static electricity, and when it is made into a paste, it tends to be inferior in the dispersion state of the powder and difficult to produce a homogeneous electrode.
- the tap density of the powder is preferably 0.5 to 2.5 g / cm 3 , particularly 1.0 to 2.0 g / cm 3 .
- the tap density of the powder is smaller than 0.5 g / cm 3 , the filling amount of the negative electrode active material per electrode unit volume is small, so that the electrode density is inferior and it is difficult to achieve high capacity.
- the tap density of the powder is larger than 2.5 g / cm 3 , the filling state of the negative electrode active material is too high, and the electrolyte does not easily permeate, and a sufficient capacity may not be obtained.
- the tap density here means a value measured under the conditions of a tapping stroke of 18 mm, a tapping frequency of 180 times, and a tapping speed of 1 time / second.
- a general pulverizer or classifier is used.
- a mortar, a ball mill, a vibrating ball mill, a satellite ball mill, a planetary ball mill, a jet mill, a sieve, a centrifugal separator, an air classification, or the like is used.
- the negative electrode active material for an electricity storage device is manufactured, for example, by heating and melting raw material powder to vitrify it.
- An oxide containing Sn is likely to change the oxidation state of Sn atoms depending on the melting condition, and the bond energy of electrons is likely to change.
- the valence of Sn ions in the negative electrode material can be reduced.
- (Pl-Pm) can be reduced, and an electric storage device having excellent initial charge / discharge efficiency can be obtained.
- a reducing gas In order to melt in a reducing atmosphere, it is preferable to supply a reducing gas into the melting tank.
- a mixed gas containing 90% to 99.5% N 2 , 0.5% to 10% H 2 , particularly 92% to 99% N 2 , and 1% to 8% H 2 is used. preferable.
- an inert gas When melting in an inert atmosphere, it is preferable to supply an inert gas into the melting tank.
- the inert gas it is preferable to use any of nitrogen, argon, and helium.
- the reducing gas or the inert gas may be supplied to the upper atmosphere of the molten glass in the melting tank, may be supplied directly from the bubbling nozzle into the molten glass, or both methods may be performed simultaneously.
- the raw material powder preferably contains a metal powder or a carbon powder.
- the metal powder it is preferable to use any powder of Sn, Al, Si, and Ti. Among these, Sn and Al powders are preferably used.
- the content of the metal powder is preferably 0 to 20%, particularly 0.1 to 10% in terms of mol%.
- an excess metal lump may be deposited from the negative electrode material, or SnO in the negative electrode active material may be reduced and deposited as metallic Sn particles.
- the content of the carbon powder is preferably 0 to 20% by mass, particularly 0.05 to 10% by mass in the raw material powder.
- a composite oxide containing phosphorus and tin as the starting material powder.
- a composite oxide containing phosphorus and tin as the starting raw material powder, it is easy to obtain a negative electrode active material with few devitrified foreign substances and excellent uniformity.
- the negative electrode active material as an electrode, an electricity storage device having a stable discharge capacity can be obtained.
- the composite oxide containing phosphorus and tin include stannous pyrophosphate (Sn 2 P 2 O 7 ).
- the negative electrode of an electricity storage device such as a nonaqueous secondary battery is formed using the negative electrode material containing the negative electrode active material described above.
- the negative electrode material is obtained by adding a binder such as a thermosetting resin or a conductive auxiliary agent such as acetylene black, ketjen black, highly conductive carbon black, or graphite to the negative electrode active material. .
- the negative electrode active material and the negative electrode material of the present invention are not limited to lithium ion secondary batteries, but other nonaqueous secondary batteries, and further, positive electrode materials and lithium ion secondary batteries for nonaqueous electric double layer capacitors It can also be applied to a hybrid capacitor combined with a negative electrode material.
- a lithium-ion capacitor which is a hybrid capacitor, is a type of asymmetric capacitor that has different charge / discharge principles for the positive and negative electrodes.
- the lithium ion capacitor has a structure in which a negative electrode for a lithium ion secondary battery and a positive electrode for an electric double layer capacitor are combined.
- the positive electrode forms an electric double layer on the surface and is charged / discharged by utilizing a physical action (electrostatic action), whereas the negative electrode has a lithium ion chemistry similar to the lithium ion secondary battery described above. Charge and discharge by reaction (occlusion and release).
- a positive electrode material made of carbonaceous powder having a high specific surface area such as activated carbon, polyacene, or mesophase carbon is used.
- the negative electrode the negative electrode material of the present invention in which lithium ions and electrons are occluded can be used.
- the means for occluding lithium ions and electrons in the negative electrode active material of the present invention is not particularly limited.
- a metal lithium electrode as a supply source of lithium ions and electrons may be disposed in a capacitor cell, and may be brought into contact with the negative electrode containing the negative electrode active material of the present invention directly or through a conductor, or in another cell.
- the negative electrode active material may be preliminarily occluded with lithium ions and electrons and then incorporated into the capacitor cell.
- stannous pyrophosphate (Sn 2 P 2 O 7 ) is used as the main raw material, and the raw material powder is made of various oxides, phosphate raw materials, carbonate raw materials, metals, carbon raw materials and the like. Prepared. The raw material powder was put into an alumina crucible and melted at 950 ° C. for 40 minutes in a nitrogen atmosphere using an electric furnace to be vitrified.
- the molten glass was poured out between a pair of rotating rollers and molded into a film having a thickness of 0.1 to 2 mm while rapidly cooling to obtain a glass sample.
- the glass sample was pulverized with an alumina separator and then passed through a sieve having an opening of 20 ⁇ m to obtain a glass powder having a mean particle size of 5 ⁇ m (a negative electrode active material for a non-aqueous secondary battery).
- the structure was identified by powder X-ray diffraction measurement for each sample.
- the negative electrode active materials of Examples 1 to 6 except Example 5 were amorphous, and no crystals were detected. In Example 5, fine crystal precipitation of SnO 2 was confirmed in the amorphous material, and the crystallinity Xc was 4%. Since the negative electrode active material of Comparative Example 1 had deliquescence immediately after production, the precipitated crystals were not measurable.
- the negative electrode active materials of Comparative Examples 2 and 3 had a structure in which an amorphous part and a crystalline part were mixed.
- Charging / discharging test Charging (occlusion of lithium ions into the negative electrode active material) was performed by CC (constant current) charging from 2 V to 0 V at 0.2 mA. Next, discharge (release of lithium ions from the negative electrode active material) was discharged from 0 V to 2 V at a constant current of 0.2 mA. This charge / discharge cycle was repeated.
- Table 1 shows the results of the initial charge / discharge characteristics when the charge / discharge test was performed on each sample, and the cycle characteristics when repeatedly charged / discharged.
- the initial discharge capacity of the batteries using the negative electrode active materials of Examples 1 to 6 was 680 mAh / g or more, and the discharge capacity at the 50th cycle was good at 382 mAh / g or more.
- the negative electrode active material of Comparative Example 1 had deliquescence immediately after production and could not be used as a non-aqueous secondary battery electrode.
- the battery using the negative electrode active material of Comparative Example 2 had a low initial discharge capacity of 392 mAh / g.
- the battery using the negative electrode active material of Comparative Example 3 had an initial discharge capacity of 901 mAh / g, but the discharge capacity at the 50th cycle was significantly reduced to 52 mAh / g.
- a composite oxide of tin and phosphorus (stannous pyrophosphate: Sn 2 P 2 O 7 ) is used as a main raw material so that the compositions shown in Tables 2 and 3 are used.
- the raw material powder was put into a quartz crucible and melted at 950 ° C. for 40 minutes in a nitrogen atmosphere using an electric furnace to be vitrified.
- the molten glass was poured out between a pair of rotating rollers and molded while being rapidly cooled to obtain a film-like glass having a thickness of 0.1 to 2 mm.
- This film-like glass was put into a ball mill using zirconia balls having a diameter of 2 to 3 cm, pulverized at 100 rpm for 3 hours, and then passed through a resin sieve having an opening of 120 ⁇ m, and a coarse glass particle having an average particle diameter D 50 of 8 to 15 ⁇ m.
- a powder was obtained.
- the glass coarse powder was put into a ball mill using zirconia balls of ⁇ 5 mm, ethanol was added and pulverized at 40 rpm for 5 hours, and then dried at 200 ° C. for 4 hours to obtain a glass powder having an average particle diameter of 2 to 5 ⁇ m ( Negative electrode active material for non-aqueous secondary battery) was obtained.
- the crystal structure was identified by performing powder X-ray diffraction measurement for each sample.
- the negative electrode active materials of Examples 1 to 4 and 6 were amorphous, and no crystals were detected.
- Example 5 was almost amorphous, but some crystals were detected.
- Tube voltage / tube current 40 kV / 40 mA Divergence / scattering slit: 1 ° Receiving slit: 0.15mm Sampling width: 0.01 ° Measurement range: 10-60 ° Measurement speed: 0.1 ° / sec Integration count: 5 times
- amorphous halos other than crystalline diffraction lines were smoothed in a diffraction line profile in the range of 10 to 60 °. Specifically, based on the Savitzky-Golay filter method, smoothing was performed with 99 data points using a parabolic filter, and then the range of 2 ⁇ between 10 and 45 ° was trimmed. The diffraction line profile was fitted linearly (see FIG. 2) so that the intensity of the diffraction line profile did not become negative within this range, and the background was subtracted.
- Peak component P1 In the diffraction line profile obtained by subtracting the background, the peak component P1 in which the 2 ⁇ value of the peak apex is fixed at 22.5 ° and the peak apex is not fixed on the higher angle side than 22.5 ° Peak component P2 was created (here, peak component P1 is derived from the phosphoric acid component in the negative electrode material. Peak component P2 is derived from the tin component in the negative electrode material, and the 2 ⁇ value at the apex reflects the oxidation state of tin) is doing).
- test battery The working electrode was placed on the lower lid of the coin cell so that the copper foil surface was facing downward, and then dried on a polypropylene porous membrane having a diameter of 16 mm (Hoechst) at 60 ° C. for 8 hours under reduced pressure.
- a test battery was produced by laminating a separator made of Celanese Cellguard # 2400) and metallic lithium as a counter electrode.
- the test battery was assembled in an environment with a dew point temperature of ⁇ 60 ° C. or lower.
- Charging / discharging test Charging (occlusion of lithium ions into the negative electrode material) performed CC (constant current) charging from 2 V to 0 V at 0.2 mA.
- discharge release of lithium ions from the negative electrode material was discharged from 0 V to 2 V at a constant current of 0.2 mA. This charge / discharge cycle was repeated.
- Tables 2 and 3 show the results of the initial charge / discharge characteristics when the charge / discharge test was performed and the cycle characteristics when the battery was repeatedly charged / discharged, with respect to the batteries using the negative electrode active materials of Examples and Comparative Examples.
- the initial discharge capacity of the batteries using the negative electrode active materials of Examples 1 to 6 was 670 mAh / g or more, and the discharge capacity at the 50th cycle was favorable to 411 mAh / g or more.
- the battery using the negative electrode active material of Comparative Example 1 had a low initial discharge capacity of 392 mAh / g.
- the battery using the negative electrode active material of Comparative Example 2 had an initial discharge capacity of 901 mAh / g, but the discharge capacity at the 50th cycle was significantly reduced to 52 mAh / g.
- the molten glass was poured out between a pair of rotating rollers and molded while being rapidly cooled to obtain a film-like glass having a thickness of 0.1 to 2 mm.
- This film-like glass was put into a ball mill using zirconia balls having a diameter of 2 to 3 cm, pulverized at 100 rpm for 3 hours, and then passed through a resin sieve having an opening of 120 ⁇ m, and a coarse glass particle having an average particle diameter D 50 of 8 to 15 ⁇ m.
- a powder was obtained.
- the glass coarse powder was put into a ball mill using zirconia balls of ⁇ 5 mm, ethanol was added and pulverized at 40 rpm for 5 hours, and then dried at 200 ° C. for 4 hours to obtain a glass powder having an average particle diameter of 2 to 5 ⁇ m ( Negative electrode active material for non-aqueous secondary battery) was obtained.
- the pure material sample was used as it was as the negative electrode active material.
- Powder X-ray diffraction (powder XRD) measurement The crystal structure was identified by performing the powder X-ray diffraction measurement for each sample. A diffraction line profile was obtained by measuring each sample under the following conditions using RINT2000 manufactured by RIGAKU as a powder X-ray diffraction measurement apparatus and Cu-K ⁇ ray as an X-ray source.
- Tube voltage / tube current 40 kV / 40 mA Divergence / scattering slit: 1 ° Receiving slit: 0.15mm Sampling width: 0.01 ° Measurement range: 10-60 ° Measurement speed: 0.1 ° / sec Integration count: 5 times
- Table 4 shows the precipitated crystal phase and crystallinity of the negative electrode active material.
- the negative electrode active materials of Examples 1 to 4 and 6 were amorphous, and no crystals were detected.
- Example 5 was almost amorphous, but some crystals were detected.
- the SnO raw material was oxidized, and SnO 2 crystals and SnO crystals were detected.
- SnO crystals were detected, and in Comparative Example 3, metal Sn crystals were detected at a rate of 100%.
- test battery (4) Production of test battery
- the above working electrode was placed on the lower lid of the coin cell so that the copper foil surface was facing downward, and then dried on a polypropylene porous membrane having a diameter of 16 mm (Hoechst) dried at 60 ° C. for 8 hours under reduced pressure.
- a test battery was produced by laminating a separator made of Celanese Cellguard # 2400) and metallic lithium as a counter electrode.
- the test battery was assembled in an environment with a dew point temperature of ⁇ 60 ° C. or lower.
- Table 4 shows the results when the coin cells were charged / discharged.
- the charge (Occlusion of Li ions in the negative electrode active material) was CC (constant current) charge up to 0 V at 0.2 mA.
- discharge release of Li ions from the negative electrode active material was discharged to 1 V at a constant current of 0.2 mA. This charge / discharge was repeated to evaluate the cycle characteristics of the negative electrode.
- (6) XRD measurement of the negative electrode active material at the time of completion of charging / discharging The negative electrode is taken out from the coin cell when charging is completed to 0V and the coin cell when discharging is completed to 1V, and the negative electrode is immersed in dimethyl carbonate (DMC). And washed. Thereafter, the negative electrode was dried under reduced pressure at room temperature overnight.
- a M06XCE manufactured by Bruker AXS was used as an X-ray diffraction measurement apparatus, and a diffraction line profile of the negative electrode active material in the negative electrode was obtained by measurement under the following conditions using Cu-K ⁇ rays as the X-ray source.
- Tube voltage / tube current 40 kV / 100 mA Divergence / scattering slit: 1 ° Receiving slit: 0.15mm Sampling width: 0.02 ° Measurement range: 5 to 70 °
- Table 5 shows the results of the peak apex and the half-value width obtained from the diffraction line profile of the negative electrode active material after completion of charging and discharging in the comparative example
- Table 6 shows the comparative example. Further, the composition of the negative electrode active material after completion of the discharge is shown in mol%.
- the Sn component shows a value converted as SnO.
- the discharge capacity at the 50th cycle of the batteries using the negative electrode active materials of Examples 1 to 6 was as good as 406 mAh / g or more.
- the initial discharge capacity was remarkably lowered to 50 mAh / g or less at the 50th cycle.
- a composite oxide of tin and phosphorus (stannous pyrophosphate: Sn2P2O7) is used as the main raw material so that the compositions shown in Tables 7 and 8 are used, and raw material powders with various oxides, carbonate raw materials, metals, carbon raw materials, etc. was prepared.
- the raw material powder was put into an alumina crucible and melted at 950 ° C. for 40 minutes in a nitrogen atmosphere using an electric furnace to be vitrified.
- the molten glass was poured out between a pair of rotating rollers, and molded while being rapidly cooled by the rotating roller to obtain a film-like glass having a thickness of 0.1 to 2 mm.
- the glass film was pulverized with an alumina separator and then passed through a sieve having an opening of 20 ⁇ m to obtain glass powder having an average particle size of 5 ⁇ m (negative electrode for non-aqueous secondary battery) Material).
- the glass film was subjected to alcohol wet pulverization using a bead mill.
- alcoholic wet pulverization was performed on the film-like glass using a ball mill.
- Example 17 the film-like glass was dry-ground using a ball mill and passed through a sieve having an opening of 75 ⁇ m.
- metal Sn powder manufactured by Kanto Chemical Co., Inc.
- the structure was identified by measuring powder X-ray diffraction for each sample.
- the negative electrode active materials of Examples 3 to 7, 9 to 13, and 15 to 17 were amorphous, and no crystals were detected.
- Examples 1, 2, 8, and 14 were almost amorphous, but some crystals were detected.
- a sample for evaluation was prepared by depositing gold with a film thickness of 30 nm in vacuum using an ion sputtering apparatus (Quick Auto Coater JFC-1500, manufactured by JEOL). It was.
- the powder sample was dispersed in a silicon resin and cured, and then gold was vapor-deposited on the surface in the same manner as the film-like sample to prepare an evaluation sample.
- XPS X-ray Electron Spectroscopy
- Perkin Elmer PHI MODEL 5400 ESCA was used as an X-ray electron spectroscopic spectrum measurement apparatus, and Mg—K ⁇ ray (1253.6 eV) was used as an X-ray source.
- the sample for evaluation was fixed to a sample holder with a conductive carbon tape, then introduced into the XPS apparatus, and allowed to stand for 1 hour under reduced pressure in a preliminary chamber in the apparatus. Next, the sample for evaluation was loaded into a measurement chamber of ultra-vacuum (10-8 Pa level). The measurement position was adjusted so that information of gold deposited on the sample surface and the measurement sample could be obtained simultaneously.
- sample surface was cleaned by etching with Ar ions.
- the tap density was measured using the powder tester PT-S manufactured by Hosokawa Micron Corporation under the conditions described above.
- the BET specific surface area was measured using FlowSorbII2200 manufactured by Micromeritex.
- test battery was assembled in an environment with a dew point temperature of ⁇ 60 ° C. or lower.
- Charging / discharging test Charging (occlusion of lithium ions into the negative electrode material) performed CC (constant current) charging from 2 V to 0 V at 0.2 mA. Next, discharge (release of lithium ions from the negative electrode active material) was discharged from 0 V to 2 V at a constant current of 0.2 mA. This charge / discharge cycle was repeated.
- Tables 7 to 9 show the results of the initial charge / discharge characteristics when the charge / discharge test was performed and the cycle characteristics when the battery was repeatedly charged / discharged, with respect to the batteries using the negative electrode active materials of Examples and Comparative Examples.
- the bond energy difference (Pl-Pm) by XPS in Examples 1 to 14 was in the range of 1.6 to 3.2 eV, and the initial charge / discharge efficiency was excellent at 52% or more.
- Comparative Example 1 since the binding energy difference (Pl-Pm) by XPS was as large as 3.6 eV, the initial charge / discharge efficiency was as low as 47%.
- the discharge capacity was 253 mAh / g or more even after repeated charging and discharging for 20 cycles.
- the difference in binding energy (Pl-Pm) by XPS in Examples 15 to 17 is 2.4 eV, the initial charge / discharge efficiency is 54% or more, and the discharge capacity after 20 cycles of repeated charge / discharge is 407 mAh / g or more. It was excellent. In particular, since Example 16 had a predetermined powder property and a homogeneous electrode could be produced, the initial charge / discharge efficiency and cycle characteristics were excellent.
- the negative electrode active material for an electricity storage device of the present invention is suitable for a portable electronic device such as a notebook computer or a mobile phone, a lithium ion non-aqueous secondary battery used for an electric vehicle, and a hybrid capacitor such as a lithium ion capacitor. is there.
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- General Chemical & Material Sciences (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Inorganic Chemistry (AREA)
- Battery Electrode And Active Subsutance (AREA)
Abstract
Description
Sn+yLi++ye-←→LiySn ・・・(2) Sn x + + xe − → Sn (1)
Sn + yLi + + ye − ← → Li y Sn (2)
Sn+yLi++ye-←→LiySn ・・・(2) Sn x + + xe − → Sn (1)
Sn + yLi + + ye − ← → Li y Sn (2)
Sn+yLi++ye-←→LiySn ・・・(2) Sn x + + xe − → Sn (1)
Sn + yLi + + ye − ← → Li y Sn (2)
表1に実施例1~6および比較例1~3を示した。各負極活物質は、以下のようにして作製した。 (1) Production of negative electrode active material for non-aqueous secondary battery Table 1 shows Examples 1 to 6 and Comparative Examples 1 to 3. Each negative electrode active material was produced as follows.
実施例および比較例のガラス粉末(負極活物質)に対し、バインダーとしてポリイミド樹脂、導電性物質としてケッチェンブラックを、ガラス粉末:バインダー:導電性物質=85:10:5(質量比)となるように秤量し、これらをN-メチルピロリドン(NMP)に分散した後、自転・公転ミキサーで十分に撹拌してスラリー状の負極材料を得た。次に、隙間150μmのドクターブレードを用いて、負極集電体である厚さ20μmの銅箔上に、得られたスラリーをコートし、乾燥機にて70℃で乾燥後、一対の回転ローラー間に通してプレスすることにより電極シートを得た。電極シートを電極打ち抜き機で直径11mmに打ち抜き、10時間200℃で減圧しながらイミド化させ、円形の作用極を得た。 (2) Production of Negative Electrode For the glass powders (negative electrode active materials) of Examples and Comparative Examples, polyimide resin as a binder, ketjen black as a conductive material, glass powder: binder: conductive material = 85: 10: 5 (Mass ratio) was weighed, and these were dispersed in N-methylpyrrolidone (NMP), and then sufficiently stirred by a rotation / revolution mixer to obtain a slurry-like negative electrode material. Next, using a doctor blade with a gap of 150 μm, the obtained slurry was coated on a copper foil having a thickness of 20 μm as a negative electrode current collector, dried at 70 ° C. with a dryer, and then between a pair of rotating rollers. An electrode sheet was obtained by pressing through a sheet. The electrode sheet was punched to a diameter of 11 mm with an electrode punching machine and imidized while reducing pressure at 200 ° C. for 10 hours to obtain a circular working electrode.
コインセルの下蓋に、上記作用極を銅箔面を下に向けて載置し、その上に60℃で8時間減圧乾燥した直径16mmのポリプロピレン多孔質膜(ヘキストセラニーズ社製 セルガード#2400)からなるセパレータ、および対極である金属リチウムを積層し、試験電池を作製した。電解液としては、1M LiPF6溶液/EC(エチレンカーボネート):DEC(ジエチルカーボネート)=1:1を用いた。なお試験電池の組み立ては露点温度-60℃以下の環境で行った。 (3) Preparation of test battery The above working electrode was placed on the lower lid of the coin cell with the copper foil surface facing downward, and dried on the polypropylene for 8 hours at 60 ° C. under reduced pressure for 16 hours. A separator comprising Cellguard # 2400 manufactured by Needs Co., Ltd. and metallic lithium as a counter electrode were laminated to prepare a test battery. As the electrolytic solution, 1M LiPF 6 solution / EC (ethylene carbonate): DEC (diethyl carbonate) = 1: 1 was used. The test battery was assembled in an environment with a dew point temperature of −60 ° C. or lower.
充電(負極活物質へのリチウムイオンの吸蔵)は、0.2mAで2Vから0VまでCC(定電流)充電を行った。次に、放電(負極活物質からのリチウムイオンの放出)は、0.2mAの定電流で0Vから2Vまで放電させた。この充放電サイクルを繰り返し行った。 (4) Charging / discharging test Charging (occlusion of lithium ions into the negative electrode active material) was performed by CC (constant current) charging from 2 V to 0 V at 0.2 mA. Next, discharge (release of lithium ions from the negative electrode active material) was discharged from 0 V to 2 V at a constant current of 0.2 mA. This charge / discharge cycle was repeated.
表2および3に実施例1~6および比較例1、2を示す。各負極活物質は以下のようにして作製した。 (1) Production of negative electrode material for non-aqueous secondary battery Tables 2 and 3 show Examples 1 to 6 and Comparative Examples 1 and 2. Each negative electrode active material was produced as follows.
粉末X線回折測定装置としてRIGAKU社製RINT2000、X線源にCu-Kα線を用いて、次の条件で各試料を測定することで回折線プロファイルを得た(図1参照)。 (2) Measurement of powder X-ray diffraction (powder XRD) Diffraction line profile by measuring each sample under the following conditions using RINT2000 made by RIGAKU as a powder X-ray diffraction measurement device and using Cu-Kα ray as an X-ray source. Was obtained (see FIG. 1).
発散・散乱スリット:1°
受光スリット:0.15mm
サンプリング幅:0.01°
測定範囲:10~60°
測定速度:0.1°/sec
積算回数:5回 Tube voltage / tube current: 40 kV / 40 mA
Divergence / scattering slit: 1 °
Receiving slit: 0.15mm
Sampling width: 0.01 °
Measurement range: 10-60 °
Measurement speed: 0.1 ° / sec
Integration count: 5 times
解析・定量ソフトとしてMaterials Data Inc.製JADE Ver.6.0を用いて、以下の手順により前記回折線プロファイルのデータ解析を行った。 (3) Analysis and data analysis Materials Data Inc. as analysis / quantification software. JADE Ver. Using 6.0, the data analysis of the diffraction line profile was performed by the following procedure.
上記で得られたガラス粉末(負極活物質)に対し、バインダーとしてポリイミド樹脂、導電性物質としてケッチェンブラックを、ガラス粉末:バインダー:導電性物質=85:10:5(重量比)の割合となるように秤量し、N-メチルピロリドン(NMP)に分散した後、自転・公転ミキサーで十分に撹拌してスラリー状の負極材料を得た。次に、隙間150μmのドクターブレードを用いて、得られたスラリーを負極集電体である厚さ20μmの銅箔上にコートし、乾燥機を用いて70℃で乾燥後、一対の回転ローラー間に通してプレスすることにより電極シートを得た。この電極シートを電極打ち抜き機で直径11mmに打ち抜き、200℃で10時間減圧乾燥することでポリイミド樹脂をイミド化させて円形の作用極を得た。 (4) Production of Negative Electrode For the glass powder (negative electrode active material) obtained above, polyimide resin as a binder and ketjen black as a conductive substance, glass powder: binder: conductive substance = 85: 10: 5 ( Weight ratio) and dispersed in N-methylpyrrolidone (NMP), and then sufficiently stirred with a rotation / revolution mixer to obtain a slurry-like negative electrode material. Next, using a doctor blade with a gap of 150 μm, the obtained slurry was coated on a 20 μm thick copper foil as a negative electrode current collector, dried at 70 ° C. using a dryer, and then between a pair of rotating rollers. An electrode sheet was obtained by pressing through a sheet. This electrode sheet was punched to a diameter of 11 mm with an electrode punching machine and dried under reduced pressure at 200 ° C. for 10 hours to imidize the polyimide resin to obtain a circular working electrode.
コインセルの下蓋に、上記作用極を銅箔面が下向きになるように載置し、その上に60℃で8時間減圧乾燥した直径16mmのポリプロピレン多孔質膜(ヘキストセラニーズ社製セルガード#2400)からなるセパレータ、および対極である金属リチウムを積層し、試験電池を作製した。電解液としては、1M LiPF6溶液/EC:DEC=1:1(EC=エチレンカーボネート、DEC=ジエチルカーボネート)を用いた。なお試験電池の組み立ては露点温度-60℃以下の環境で行った。 (5) Production of test battery The working electrode was placed on the lower lid of the coin cell so that the copper foil surface was facing downward, and then dried on a polypropylene porous membrane having a diameter of 16 mm (Hoechst) at 60 ° C. for 8 hours under reduced pressure. A test battery was produced by laminating a separator made of Celanese Cellguard # 2400) and metallic lithium as a counter electrode. As the electrolytic solution, 1M LiPF 6 solution / EC: DEC = 1: 1 (EC = ethylene carbonate, DEC = diethyl carbonate) was used. The test battery was assembled in an environment with a dew point temperature of −60 ° C. or lower.
充電(負極材料へのリチウムイオンの吸蔵)は、0.2mAで2Vから0VまでCC(定電流)充電を行った。次に、放電(負極材料からのリチウムイオンの放出)は、0.2mAの定電流で0Vから2Vまで放電させた。この充放電サイクルを繰り返し行った。 (6) Charging / discharging test Charging (occlusion of lithium ions into the negative electrode material) performed CC (constant current) charging from 2 V to 0 V at 0.2 mA. Next, discharge (release of lithium ions from the negative electrode material) was discharged from 0 V to 2 V at a constant current of 0.2 mA. This charge / discharge cycle was repeated.
表4に示す組成となるように、主原料としてスズとリンの複合酸化物(ピロリン酸第一錫:Sn2P2O7)を用い、各種酸化物、炭酸塩原料などで原料粉末を調製した。原料粉末を石英ルツボに投入し、電気炉を用いて窒素雰囲気にて950℃、40分間の溶融を行い、ガラス化した。 (1) Production of negative electrode active material for non-aqueous secondary battery A composite oxide of tin and phosphorus (stannous pyrophosphate: Sn 2 P 2 O 7 ) was used as the main raw material so as to have the composition shown in Table 4. Raw material powders were prepared from various oxides and carbonate raw materials. The raw material powder was put into a quartz crucible and melted at 950 ° C. for 40 minutes in a nitrogen atmosphere using an electric furnace to be vitrified.
各試料について粉末X線回折測定を行うことにより結晶構造を同定した。粉末X線回折測定装置としてRIGAKU社製RINT2000、X線源にCu-Kα線を用いて、次の条件で各試料を測定することで回折線プロファイルを得た。 (2) Powder X-ray diffraction (powder XRD) measurement The crystal structure was identified by performing the powder X-ray diffraction measurement for each sample. A diffraction line profile was obtained by measuring each sample under the following conditions using RINT2000 manufactured by RIGAKU as a powder X-ray diffraction measurement apparatus and Cu-Kα ray as an X-ray source.
発散・散乱スリット:1°
受光スリット:0.15mm
サンプリング幅:0.01°
測定範囲:10~60°
測定速度:0.1°/sec
積算回数:5回 Tube voltage / tube current: 40 kV / 40 mA
Divergence / scattering slit: 1 °
Receiving slit: 0.15mm
Sampling width: 0.01 °
Measurement range: 10-60 °
Measurement speed: 0.1 ° / sec
Integration count: 5 times
上記で得られたガラス粉末(負極活物質)に対し、バインダーとしてポリイミド樹脂、導電性物質としてケッチェンブラックを、ガラス粉末:バインダー:導電性物質=85:10:5(重量比)の割合となるように秤量し、N-メチルピロリドン(NMP)に分散した後、自転・公転ミキサーで十分に撹拌してスラリー状の負極材料を得た。次に、隙間150μmのドクターブレードを用いて、得られた負極材料を負極集電体である厚さ20μmの銅箔上にコートし、乾燥機を用いて70℃で乾燥後、一対の回転ローラー間に通してプレスすることにより電極シートを得た。この電極シートを電極打ち抜き機で直径11mmに打ち抜き、200℃で10時間減圧乾燥することでポリイミド樹脂をイミド化させて円形の作用極(負極)を得た。 (3) Production of Negative Electrode For the glass powder (negative electrode active material) obtained above, polyimide resin as binder and ketjen black as conductive substance, glass powder: binder: conductive substance = 85: 10: 5 ( Weight ratio) and dispersed in N-methylpyrrolidone (NMP), and then sufficiently stirred with a rotation / revolution mixer to obtain a slurry-like negative electrode material. Next, using a doctor blade with a gap of 150 μm, the obtained negative electrode material was coated on a 20 μm thick copper foil as a negative electrode current collector, dried at 70 ° C. using a dryer, and then a pair of rotating rollers An electrode sheet was obtained by pressing in between. This electrode sheet was punched to a diameter of 11 mm with an electrode punching machine and dried under reduced pressure at 200 ° C. for 10 hours to imidize the polyimide resin to obtain a circular working electrode (negative electrode).
コインセルの下蓋に、上記作用極を銅箔面が下向きになるように載置し、その上に60℃で8時間減圧乾燥した直径16mmのポリプロピレン多孔質膜(ヘキストセラニーズ社製セルガード#2400)からなるセパレータ、および対極である金属リチウムを積層し、試験電池を作製した。電解液としては、1M LiPF6溶液/EC:DEC=1:1(EC=エチレンカーボネート、DEC=ジエチルカーボネート)を用いた。なお試験電池の組み立ては露点温度-60℃以下の環境で行った。 (4) Production of test battery The above working electrode was placed on the lower lid of the coin cell so that the copper foil surface was facing downward, and then dried on a polypropylene porous membrane having a diameter of 16 mm (Hoechst) dried at 60 ° C. for 8 hours under reduced pressure. A test battery was produced by laminating a separator made of Celanese Cellguard # 2400) and metallic lithium as a counter electrode. As the electrolytic solution, 1M LiPF 6 solution / EC: DEC = 1: 1 (EC = ethylene carbonate, DEC = diethyl carbonate) was used. The test battery was assembled in an environment with a dew point temperature of −60 ° C. or lower.
表4に前記コインセルを充放電した際の結果を示す。評価条件として、充電(負極活物質へのLiイオンの吸蔵)は、0.2mAで0VまでCC(定電流)充電を行った。次に、放電(負極活物質からのLiイオンの放出)は、0.2mAの定電流で1Vまで放電させた。この充放電を繰り返し行い負極のサイクル特性を評価した。 (5) Evaluation test of charge / discharge characteristics Table 4 shows the results when the coin cells were charged / discharged. As an evaluation condition, the charge (Occlusion of Li ions in the negative electrode active material) was CC (constant current) charge up to 0 V at 0.2 mA. Next, discharge (release of Li ions from the negative electrode active material) was discharged to 1 V at a constant current of 0.2 mA. This charge / discharge was repeated to evaluate the cycle characteristics of the negative electrode.
0Vまで充電完了させた時のコインセルおよび1Vまで放電完了させた時のコインセルから負極を取り出し、炭酸ジメチル(DMC)中に当該負極を浸漬して洗浄した。この後、負極を室温下で一晩減圧乾燥させた。X線回折測定装置としてBruker AXS社製 M06XCEを用い、X線源にCu-Kα線を用いて次の条件で測定することで負極中の負極活物質の回折線プロファイルを得た。 (6) XRD measurement of the negative electrode active material at the time of completion of charging / discharging The negative electrode is taken out from the coin cell when charging is completed to 0V and the coin cell when discharging is completed to 1V, and the negative electrode is immersed in dimethyl carbonate (DMC). And washed. Thereafter, the negative electrode was dried under reduced pressure at room temperature overnight. A M06XCE manufactured by Bruker AXS was used as an X-ray diffraction measurement apparatus, and a diffraction line profile of the negative electrode active material in the negative electrode was obtained by measurement under the following conditions using Cu-Kα rays as the X-ray source.
発散・散乱スリット:1°
受光スリット:0.15mm
サンプリング幅:0.02°
測定範囲:5~70° Tube voltage / tube current: 40 kV / 100 mA
Divergence / scattering slit: 1 °
Receiving slit: 0.15mm
Sampling width: 0.02 °
Measurement range: 5 to 70 °
解析・定量ソフトとしてMaterials Data Inc.製JADE Ver.6.0を用いて、前記回折線プロファイルのデータ解析を行った。まず、5~70°の範囲における回折線プロファイルからバックグラウンドの回折線プロファイルを差し引いて負極活物質の回折線プロファイルを得た(図4、5)。この回折線プロファイルにおいてそれぞれの回折線ピークのピーク頂点と半価幅(FWHM)を求めた。 (7) Analysis and data analysis Materials Data Inc. as analysis / quantification software. JADE Ver. Data analysis of the diffraction line profile was performed using 6.0. First, the diffraction line profile of the negative electrode active material was obtained by subtracting the background diffraction line profile from the diffraction line profile in the range of 5 to 70 ° (FIGS. 4 and 5). In this diffraction line profile, the peak apex and half width (FWHM) of each diffraction line peak were determined.
表7および8に実施例1~14および比較例1、2を示す。各負極活物質は以下のようにして作製した。 (1) Production of negative electrode active material for non-aqueous secondary battery Tables 7 and 8 show Examples 1 to 14 and Comparative Examples 1 and 2. Each negative electrode active material was produced as follows.
(1)においてフィルム状に成形したガラスを1cm角に切断した後、表面研磨を行い、アセトンを用いて洗浄した。金属SnのSn3d5/2の結合エネルギーPmを得るための測定試料としては、関東化学社製金属スズ(粒状、純度99.9%)をプレスすることで金属板状に加工後、表面研磨し、アセトンを用いて洗浄したものを用いた。 (2) Preparation of X-ray electron spectroscopic spectrum measurement sample The glass formed into a film shape in (1) was cut into 1 cm square, then subjected to surface polishing and washed with acetone. As a measurement sample for obtaining Sn3d 5/2 binding energy Pm of metal Sn, metal tin (granularity, purity 99.9%) manufactured by Kanto Chemical Co., Ltd. is pressed into a metal plate, and then surface polished. What was washed with acetone was used.
本発明においては、X線電子分光スペクトル測定装置にPerkin Elmer Phi MODEL 5400 ESCA、X線源にMg-Kα線(1253.6eV)を用いた。前記評価用試料を導電性カーボンテープでサンプルホルダーに固定した後、XPS装置内に導入し、装置内の予備チャンバーにて減圧下、1時間静置した。ついで、評価用試料を超真空(10-8Paレベル)の測定チャンバーに装填した。測定位置は、試料表面に蒸着した金と測定試料の情報が同時に得られるように調整した。なお、試料間で評価用試料の高さ(Z軸方向)が異なると、試料表面におけるX線の焦点位置がずれ、光電子の検出強度に影響を与えるため、評価用試料は同じ高さに揃えた。 (3) X-ray Electron Spectroscopy (XPS) Measurement In the present invention, Perkin Elmer PHI MODEL 5400 ESCA was used as an X-ray electron spectroscopic spectrum measurement apparatus, and Mg—Kα ray (1253.6 eV) was used as an X-ray source. The sample for evaluation was fixed to a sample holder with a conductive carbon tape, then introduced into the XPS apparatus, and allowed to stand for 1 hour under reduced pressure in a preliminary chamber in the apparatus. Next, the sample for evaluation was loaded into a measurement chamber of ultra-vacuum (10-8 Pa level). The measurement position was adjusted so that information of gold deposited on the sample surface and the measurement sample could be obtained simultaneously. Note that if the height of the sample for evaluation (Z-axis direction) differs between samples, the focal position of the X-rays on the surface of the sample shifts and affects the detection intensity of photoelectrons, so the samples for evaluation are aligned at the same height. It was.
イオン電流:3μA
ラスター範囲:50%×50%(50mm×50mm)
加速電圧:3kV
イオン銃内エミッション電流:25mA
エッチング時間:2分間
<測定条件>
各元素のスペクトル領域にて、
リピート回数:3
サイクル回数:5
X線出力:15kV 400W
パスエネルギー:44.75eV
測定ステップ:0.1eV
各ステップ時間:50ms
分析面積:0.6mmφ、
検出角度:45° <Etching conditions>
Ion current: 3 μA
Raster range: 50% x 50% (50mm x 50mm)
Acceleration voltage: 3 kV
Emission current in ion gun: 25 mA
Etching time: 2 minutes <Measurement conditions>
In the spectral region of each element,
Repeat count: 3
Number of cycles: 5
X-ray output: 15kV 400W
Pass energy: 44.75 eV
Measurement step: 0.1 eV
Each step time: 50ms
Analysis area: 0.6 mmφ
Detection angle: 45 °
解析・定量ソフトとしてPHI MaltiPak Ver.6.0を用いて、前記XPSスペクトルのデータ解析を行った。まず、内部標準物質として付着させた金のAu4f7/2軌道を83.8eVの値に帯電補正した。次いで、負極活物質および金属SnのSn原子の3d5/2における結合エネルギー値PlおよびPmをそれぞれ求めた。表1および2に各試料のPlとPmおよび結合エネルギー差(Pl-Pm)を示した。 (4) Analysis and data analysis As analysis / quantification software, PHI MultiPak Ver. Data analysis of the XPS spectrum was performed using 6.0. First, the gold Au4f 7/2 orbit deposited as an internal standard substance was corrected to a charge of 83.8 eV. Next, the binding energy values Pl and Pm at 3d 5/2 of the Sn atoms of the negative electrode active material and the metal Sn were obtained, respectively. Tables 1 and 2 show the Pl and Pm of each sample and the binding energy difference (Pl-Pm).
平均粒子径D50および最大粒子径D100は、株式会社島津製作所製レーザー回折式粒度分布測定装置SALD-2000Jを用いて測定した。 (5) Measurement of powder properties The average particle size D50 and the maximum particle size D100 were measured using a laser diffraction particle size distribution analyzer SALD-2000J manufactured by Shimadzu Corporation.
上記で得られたガラス粉末(負極活物質)に対し、バインダーとしてポリフッ化ビニリデン(PVDF)、導電性物質としてケッチェンブラックを、ガラス粉末:バインダー:導電性物質=85:10:5(重量比)の割合となるように秤量し、N-メチルピロリドン(NMP)に分散した後、自転・公転ミキサーで十分に撹拌してスラリー状の負極材料を得た。次に、隙間150μmのドクターブレードを用いて、得られたスラリーを負極集電体である厚さ20μmの銅箔上にコートし、70℃の乾燥機で乾燥後、一対の回転ローラー間に通してプレスすることにより電極シートを得た。この電極シートを電極打ち抜き機で直径11mmに打ち抜き、120℃で3時間減圧乾燥を行い、円形の作用極を得た。 (6) Production of Negative Electrode For the glass powder (negative electrode active material) obtained above, polyvinylidene fluoride (PVDF) as a binder, ketjen black as a conductive substance, glass powder: binder: conductive substance = 85: The mixture was weighed to a ratio of 10: 5 (weight ratio), dispersed in N-methylpyrrolidone (NMP), and then sufficiently stirred by a rotation / revolution mixer to obtain a slurry-like negative electrode material. Next, using a doctor blade with a gap of 150 μm, the obtained slurry was coated on a 20 μm thick copper foil as a negative electrode current collector, dried with a dryer at 70 ° C., and then passed between a pair of rotating rollers. To obtain an electrode sheet. This electrode sheet was punched to a diameter of 11 mm with an electrode punching machine and dried under reduced pressure at 120 ° C. for 3 hours to obtain a circular working electrode.
コインセルの下蓋に、上記作用極を銅箔面を下に向けて載置し、その上に60℃で8時間減圧乾燥した直径16mmのポリプロピレン多孔質膜(ヘキストセラニーズ社製 セルガード#2400)からなるセパレータ、および対極である金属リチウムを積層し、試験電池を作製した。電解液としては、1M LiPF6溶液/EC(エチレンカーボネート):DEC(ジエチルカーボネート)=1:1を用いた。なお試験電池の組み立ては露点温度-60℃以下の環境で行った。 (7) Production of test battery The above working electrode was placed on the lower lid of the coin cell with the copper foil surface facing down, and dried on it at 60 ° C. for 8 hours under reduced pressure for 16 hours in diameter. A separator comprising Cellguard # 2400 manufactured by Needs Co., Ltd. and metallic lithium as a counter electrode were laminated to prepare a test battery. As the electrolytic solution, 1M LiPF 6 solution / EC (ethylene carbonate): DEC (diethyl carbonate) = 1: 1 was used. The test battery was assembled in an environment with a dew point temperature of −60 ° C. or lower.
充電(負極材料へのリチウムイオンの吸蔵)は、0.2mAで2Vから0VまでCC(定電流)充電を行った。次に、放電(負極活物質からのリチウムイオンの放出)は、0.2mAの定電流で0Vから2Vまで放電させた。この充放電サイクルを繰り返し行った。 (8) Charging / discharging test Charging (occlusion of lithium ions into the negative electrode material) performed CC (constant current) charging from 2 V to 0 V at 0.2 mA. Next, discharge (release of lithium ions from the negative electrode active material) was discharged from 0 V to 2 V at a constant current of 0.2 mA. This charge / discharge cycle was repeated.
Claims (24)
- 酸化物換算のモル%表示で、SnO 70~95%、P2O5 5~30%(SnO 70%、P2O5 30%は含まない)の組成を含有することを特徴とする蓄電デバイス用負極活物質。 An electricity storage device comprising a composition of SnO 70 to 95% and P 2 O 5 5 to 30% (not including SnO 70% and P 2 O 5 30%) in terms of mol% in terms of oxide Negative electrode active material.
- 実質的に非晶質からなることを特徴とする請求項1に記載の蓄電デバイス用負極活物質。 The negative electrode active material for an electricity storage device according to claim 1, wherein the negative electrode active material is substantially amorphous.
- 請求項1または2に記載の蓄電デバイス用負極活物質を含有する蓄電デバイス用負極材料。 A negative electrode material for an electricity storage device comprising the negative electrode active material for an electricity storage device according to claim 1 or 2.
- 請求項1または2に記載の蓄電デバイス用負極活物質を製造する方法であって、原料粉末を還元雰囲気または不活性雰囲気中で溶融してガラス化することを特徴とする蓄電デバイス用負極活物質。 A method for producing a negative electrode active material for an electricity storage device according to claim 1 or 2, wherein the raw material powder is melted and vitrified in a reducing atmosphere or an inert atmosphere. .
- 原料粉末が、リンとスズを含む複合酸化物であることを特徴とする請求項4に記載の蓄電デバイス用負極活物質の製造方法。 The method for producing a negative electrode active material for an electricity storage device according to claim 4, wherein the raw material powder is a composite oxide containing phosphorus and tin.
- 少なくともSnOとP2O5を含有する蓄電デバイス用負極活物質であって、CuKα線を用いた粉末X線回折測定によって得られる回折線プロファイルにおいて2θ値で10~45°に非晶質ハローを有し、当該範囲にて2θ値を22.5°に固定したピーク成分P1と22.5°より高角度側のピーク成分P2の二成分でカーブフィッティングした際に、P2のピーク頂点の位置が2θ値で25.0~29.0°であることを特徴とする蓄電デバイス用負極活物質。 A negative electrode active material for an electricity storage device containing at least SnO and P 2 O 5 and having an amorphous halo at 10 to 45 ° in terms of 2θ in a diffraction line profile obtained by powder X-ray diffraction measurement using CuKα rays. And when the curve fitting is performed with two components of the peak component P1 in which the 2θ value is fixed at 22.5 ° and the peak component P2 on the higher angle side than 22.5 °, the position of the peak apex of P2 is 2. A negative electrode active material for an electricity storage device, wherein the 2θ value is 25.0 to 29.0 °.
- 少なくともSnOとP2O5を含有する蓄電デバイス用負極活物質であって、CuKα線を用いた粉末X線回折測定によって得られる回折線プロファイルにおいて2θ値で10~45°に非晶質ハローを有し、当該範囲にて2θ値を22.5°に固定したピーク成分P1と22.5°より高角度側のピーク成分P2の二成分でカーブフィッティングした際に、P1のピーク面積A1とP2のピーク面積A2が、A1/A2=0.01~8の関係を満たすことを特徴とする蓄電デバイス用負極活物質。 A negative electrode active material for an electricity storage device containing at least SnO and P 2 O 5 and having an amorphous halo at 10 to 45 ° in terms of 2θ in a diffraction line profile obtained by powder X-ray diffraction measurement using CuKα rays. When the curve fitting is performed with two components of the peak component P1 having a 2θ value fixed at 22.5 ° and the peak component P2 on the higher angle side than 22.5 ° in the range, the peak areas A1 and P2 of P1 The negative electrode active material for an electricity storage device, wherein the peak area A2 satisfies the relationship of A1 / A2 = 0.01 to 8.
- モル%で、SnO 45~95%、P2O5 5~55%の組成を含有することを特徴とする請求項6または7に記載の蓄電デバイス用負極活物質。 The negative electrode active material for an electricity storage device according to claim 6 or 7, comprising a composition of SnO 45 to 95% and P 2 O 5 5 to 55% in mol%.
- 実質的に非晶質であることを特徴とする請求項6から8のいずれかに記載の蓄電デバイス用負極活物質。 The negative electrode active material for an electricity storage device according to any one of claims 6 to 8, wherein the negative electrode active material is substantially amorphous.
- 請求項6から9のいずれかに記載の蓄電デバイス用負極活物質を含有する蓄電デバイス用負極材料。 A negative electrode material for an electricity storage device, comprising the negative electrode active material for an electricity storage device according to any one of claims 6 to 9.
- 請求項6から9のいずれかに記載の蓄電デバイス用負極活物質を製造する方法であって、原料粉末を還元雰囲気または不活性雰囲気中で溶融してガラス化することを特徴とする蓄電デバイス用負極活物質の製造方法。 A method for producing a negative electrode active material for an electricity storage device according to any one of claims 6 to 9, wherein the raw material powder is melted and vitrified in a reducing atmosphere or an inert atmosphere. A method for producing a negative electrode active material.
- 原料粉末が、リンとスズを含む複合酸化物であることを特徴とする請求項11に記載の蓄電デバイス用負極活物質の製造方法。 The method for producing a negative electrode active material for an electricity storage device according to claim 11, wherein the raw material powder is a composite oxide containing phosphorus and tin.
- 少なくとも負極と正極を有する蓄電デバイスに用いられる負極活物質であって、充電完了時において、CuKα線を用いた粉末X線回折測定によって得られる回折線プロファイルの2θ値30~50°の範囲および/または2θ値10~30°の範囲に検出される回折線ピークの半価幅が0.5°以上であることを特徴とする蓄電デバイス用負極活物質。 A negative electrode active material used in an electricity storage device having at least a negative electrode and a positive electrode, and at the time of completion of charging, a 2θ value in a range of 30 to 50 ° of a diffraction line profile obtained by powder X-ray diffraction measurement using CuKα rays and / or Alternatively, a negative electrode active material for an electricity storage device, wherein a half width of a diffraction line peak detected in a range of 2θ value of 10 to 30 ° is 0.5 ° or more.
- 少なくとも負極と正極からなる蓄電デバイスに用いられる負極活物質であって、放電完了時において、CuKα線を用いた粉末X線回折測定によって得られる回折線プロファイルの2θ値15~40°の範囲に検出される回折線ピークの半価幅が0.1°以上であることを特徴とする蓄電デバイス用負極活物質。 A negative electrode active material used in power storage devices consisting of at least a negative electrode and a positive electrode, and detected at the time of completion of discharge within a 2θ value of 15 to 40 ° of the diffraction line profile obtained by powder X-ray diffraction measurement using CuKα rays A negative electrode active material for an electricity storage device, wherein the half width of the diffraction line peak is 0.1 ° or more.
- 放電完了時において、酸化物換算のモル%表示で、組成としてSnO 10~70%、Li2O 20~70%、P2O5 2~40%を含有することを特徴とする請求項13または14に記載の蓄電デバイス用負極活物質。 A composition containing SnO 10 to 70%, Li 2 O 20 to 70%, and P 2 O 5 2 to 40% in terms of oxide in terms of mol% at the completion of discharge. 14. The negative electrode active material for an electricity storage device according to 14.
- 請求項13から15のいずれかに記載の蓄電デバイス用負極活物質を含有する蓄電デバイス用負極材料。 A negative electrode material for an electricity storage device comprising the negative electrode active material for an electricity storage device according to any one of claims 13 to 15.
- 組成として少なくともSnOを含有する蓄電デバイス用負極活物質であって、当該蓄電デバイス用負極活物質中のSn原子のSn3d5/2軌道における電子の結合エネルギー値をPl、金属SnのSn3d5/2軌道における電子の結合エネルギー値をPmとしたとき、(Pl-Pm)が0.01~3.5eVであることを特徴とする蓄電デバイス用負極活物質。 A negative electrode active material for an electricity storage device containing at least SnO as a composition, wherein the binding energy value of electrons in the Sn3d 5/2 orbit of the Sn atom in the negative electrode active material for the electricity storage device is Pl, and Sn3d 5/2 of metal Sn A negative electrode active material for an electricity storage device, wherein (Pl-Pm) is 0.01 to 3.5 eV, where Pm is an electron binding energy value in orbit.
- 実質的に非晶質からなることを特徴とする請求項17に記載の蓄電デバイス用負極活物質。 The negative electrode active material for an electricity storage device according to claim 17, wherein the negative electrode active material is substantially amorphous.
- 粉末状であることを特徴とする請求項17または18に記載の蓄電デバイス用負極活物質。 The negative electrode active material for an electricity storage device according to claim 17 or 18, wherein the negative electrode active material is in a powder form.
- 平均粒子径が0.1~10μmかつ最大粒子径が75μm以下であることを特徴とする請求項19に記載の蓄電デバイス用負極活物質。 20. The negative electrode active material for an electricity storage device according to claim 19, wherein the average particle size is 0.1 to 10 μm and the maximum particle size is 75 μm or less.
- 請求項17から20のいずれかに記載の蓄電デバイス用負極活物質を含有する蓄電デバイス用負極材料。 A negative electrode material for a power storage device, comprising the negative electrode active material for a power storage device according to any one of claims 17 to 20.
- 請求項17~20のいずれかに記載の蓄電デバイス用負極活物質を製造する方法であって、原料粉末を還元雰囲気または不活性雰囲気中で溶融してガラス化することを特徴とする蓄電デバイス用負極活物質の製造方法。 A method for producing a negative electrode active material for an electricity storage device according to any one of claims 17 to 20, wherein the raw material powder is melted and vitrified in a reducing atmosphere or an inert atmosphere. A method for producing a negative electrode active material.
- 原料粉末が金属粉末または炭素粉末を含有することを特徴とする請求項22に記載の蓄電デバイス用負極活物質の製造方法。 The method for producing a negative electrode active material for an electricity storage device according to claim 22, wherein the raw material powder contains metal powder or carbon powder.
- 原料粉末が、リンとスズを含む複合酸化物であることを特徴とする請求項22または23に記載の蓄電デバイス用負極活物質の製造方法。 The method for producing a negative electrode active material for an electricity storage device according to claim 22 or 23, wherein the raw material powder is a composite oxide containing phosphorus and tin.
Priority Applications (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US13/502,582 US20120276452A1 (en) | 2009-10-22 | 2010-10-21 | Negative electrode active material for electricity storage device, and method for producing same |
CN201080044505.8A CN102549816B (en) | 2009-10-22 | 2010-10-21 | Negative electrode active material for electricity storage device and manufacture method thereof |
KR1020167023702A KR20160105986A (en) | 2009-10-22 | 2010-10-21 | Negative electrode active material for electricity storage device, and method for producing same |
US14/633,579 US20150171418A1 (en) | 2009-10-22 | 2015-02-27 | Negative electrode active material for electricity storage device, and method for producing same |
Applications Claiming Priority (10)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2009-243155 | 2009-10-22 | ||
JP2009243655 | 2009-10-22 | ||
JP2009243155 | 2009-10-22 | ||
JP2009-243655 | 2009-10-22 | ||
JP2009-267369 | 2009-11-25 | ||
JP2009267369 | 2009-11-25 | ||
JP2010-028357 | 2010-02-12 | ||
JP2010028357 | 2010-02-12 | ||
JP2010-088289 | 2010-04-07 | ||
JP2010088289A JP5597015B2 (en) | 2009-10-22 | 2010-04-07 | Negative electrode material for electricity storage device and method for producing the same |
Related Child Applications (2)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US13/502,582 A-371-Of-International US20120276452A1 (en) | 2009-10-22 | 2010-10-21 | Negative electrode active material for electricity storage device, and method for producing same |
US14/633,579 Division US20150171418A1 (en) | 2009-10-22 | 2015-02-27 | Negative electrode active material for electricity storage device, and method for producing same |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2011049158A1 true WO2011049158A1 (en) | 2011-04-28 |
Family
ID=43900381
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/JP2010/068551 WO2011049158A1 (en) | 2009-10-22 | 2010-10-21 | Negative electrode active material for electricity storage device, and method for producing same |
Country Status (1)
Country | Link |
---|---|
WO (1) | WO2011049158A1 (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN113851638A (en) * | 2021-08-27 | 2021-12-28 | 华东理工大学 | SnO (stannic oxide)2-xPreparation method and application thereof, and composite electrode |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH08236158A (en) * | 1995-02-27 | 1996-09-13 | Fuji Photo Film Co Ltd | Non aqueous secondary battery |
JPH08298121A (en) * | 1995-04-25 | 1996-11-12 | Fuji Photo Film Co Ltd | Nonaqueous secondary battery |
JPH10106563A (en) * | 1996-09-27 | 1998-04-24 | Fuji Photo Film Co Ltd | Now-aqueous secondary battery |
-
2010
- 2010-10-21 WO PCT/JP2010/068551 patent/WO2011049158A1/en active Application Filing
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH08236158A (en) * | 1995-02-27 | 1996-09-13 | Fuji Photo Film Co Ltd | Non aqueous secondary battery |
JPH08298121A (en) * | 1995-04-25 | 1996-11-12 | Fuji Photo Film Co Ltd | Nonaqueous secondary battery |
JPH10106563A (en) * | 1996-09-27 | 1998-04-24 | Fuji Photo Film Co Ltd | Now-aqueous secondary battery |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN113851638A (en) * | 2021-08-27 | 2021-12-28 | 华东理工大学 | SnO (stannic oxide)2-xPreparation method and application thereof, and composite electrode |
CN113851638B (en) * | 2021-08-27 | 2023-02-10 | 华东理工大学 | SnO (stannic oxide) 2-x Preparation method and application thereof, and composite electrode |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CN111864207B (en) | All-solid battery | |
JP6927292B2 (en) | All-solid-state lithium-ion secondary battery | |
KR20130052500A (en) | Composite, manufacturing method the composite, negative electrode active material including the composite, anode including the anode active material, and lithium secondary battery including the anode | |
JP6300176B2 (en) | Negative electrode active material for sodium secondary battery | |
JP2012182115A (en) | Method for manufacturing negative electrode active material for electricity storage device | |
JP5645056B2 (en) | Negative electrode active material for power storage device, negative electrode material for power storage device using the same, and negative electrode for power storage device | |
WO2019003903A1 (en) | Positive electrode active material for sodium-ion secondary battery | |
US20150171418A1 (en) | Negative electrode active material for electricity storage device, and method for producing same | |
JP5601615B2 (en) | NEGATIVE ELECTRODE ACTIVE MATERIAL FOR ELECTRIC STORAGE DEVICE AND METHOD FOR PRODUCING THE SAME | |
JP2017174739A (en) | Negative electrode material for nonaqueous secondary battery, and lithium ion secondary battery | |
JP2014029842A (en) | Electrode material and secondary battery using the same | |
JP5663808B2 (en) | Negative electrode material for electric storage device and negative electrode for electric storage device using the same | |
JP7405342B2 (en) | Negative electrode active material for sodium ion secondary battery and method for producing the same | |
WO2011049158A1 (en) | Negative electrode active material for electricity storage device, and method for producing same | |
JP5597015B2 (en) | Negative electrode material for electricity storage device and method for producing the same | |
JP2012204266A (en) | Negative electrode active material for electricity storage device, negative electrode material for electricity storage device containing the same, and negative electrode for electricity storage device | |
JP6241130B2 (en) | Negative electrode active material for electricity storage devices | |
JP6175906B2 (en) | Negative electrode active material for power storage device and method for producing the same | |
JP6331395B2 (en) | Negative electrode active material for power storage device and method for producing the same | |
JP6183590B2 (en) | Negative electrode active material for power storage device and method for producing the same | |
JP6794518B2 (en) | Manufacturing method of solid electrolyte material | |
JP7178278B2 (en) | Anode materials for storage devices | |
WO2013062037A1 (en) | Method for producing oxide material | |
WO2022176790A1 (en) | Negative electrode active substance for sodium ion secondary battery | |
JP2024505867A (en) | Negative electrode active material, negative electrode containing the same, secondary battery containing the same, and method for producing negative electrode active material |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
WWE | Wipo information: entry into national phase |
Ref document number: 201080044505.8 Country of ref document: CN |
|
121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 10825007 Country of ref document: EP Kind code of ref document: A1 |
|
ENP | Entry into the national phase |
Ref document number: 20127002539 Country of ref document: KR Kind code of ref document: A |
|
WWE | Wipo information: entry into national phase |
Ref document number: 13502582 Country of ref document: US |
|
122 | Ep: pct application non-entry in european phase |
Ref document number: 10825007 Country of ref document: EP Kind code of ref document: A1 |