JP5034305B2 - Non-aqueous secondary battery active material and method for producing the same - Google Patents

Description

  The present invention relates to an active material for a non-aqueous secondary battery and a method for producing the same.

  Non-aqueous secondary batteries such as lithium secondary batteries have already been put to practical use as power sources for mobile phones and laptop computers, and are also being applied to medium and large applications such as automobiles and power storage applications. Yes.

  Non-aqueous secondary batteries have been required to have a small decrease in electric capacity when charging and discharging are repeated, that is, excellent in cycle performance. In addition, the lithium secondary battery has a large electric capacity despite its small size, so it is required to improve safety in the case of an external short circuit or an internal short circuit. There has been a demand for a method for producing an active material that provides a highly non-aqueous secondary battery.

  Therefore, for a non-aqueous secondary battery in which the surface of a lithium-containing composite oxide containing nickel is coated with a compound having any of Mg, Si, Ti, Al, V, Co, K, Ca, Na, and B A method for producing a positive electrode active material has been proposed (see, for example, Patent Document 1). However, the non-aqueous secondary battery manufactured using the obtained positive electrode active material for non-aqueous secondary battery has not been sufficiently cycled and has not been sufficiently safe.

JP 2001-28265 A

  The present invention provides an active material for a non-aqueous secondary battery that provides a non-aqueous secondary battery that is superior in cycle performance and safety, and a method for producing the active material. An object is to provide a water secondary battery.

  Therefore, in order to solve the above problems, the present inventors have intensively studied a method for producing an active material for a non-aqueous secondary battery, and as a result, a specific surface is formed on the particle surface of a material that can be doped / undoped with lithium ions. Cycleability and safety by depositing a compound of a metal element to make an adherend, and further holding the adherend in an atmosphere containing water so as to increase the weight by a certain ratio, followed by firing. It became the active material for non-aqueous secondary batteries which gives the non-aqueous secondary battery excellent in this balance, and came to complete this invention.

That is, the present invention provides at least one element selected from the elements A (B, Al, Ga, In, Si, Ge, Sn, Mg, and transition metal elements on the particle surface of a material that can be doped / undoped with lithium ions. The adhering material on which the compound containing the element is adhering is adjusted so that the weight increase rate of the adhering material is in the range of 0.1 wt% or more and 5.0 wt% or less in an atmosphere containing water. A method for producing an active material for a non-aqueous secondary battery is provided, which is fired after being held.
Further, the present invention provides one kind of element A (B, Al, Ga, In, Si, Ge, Sn, Mg and a transition metal element on the particle surface of a material that can be doped / undoped with lithium ions. An active material for a non-aqueous secondary battery produced by firing an adherend containing a compound containing the above element), and when the active material is mixed with an alkaline solution, the active material The weight ratio (W ₁ ) of the element A extracted from the substance into the alkaline solution is 3.0% or less with respect to the weight ratio (W ₂ ) of the element A contained in the active material before mixing. An active material for a non-aqueous secondary battery is provided.
The active material for a non-aqueous secondary battery of the present invention can provide a non-aqueous secondary battery excellent in safety and cycleability, and can be suitably used as an active material for a non-aqueous secondary battery. .

  By using the active material for a non-aqueous secondary battery produced by the production method of the present invention or the active material for a non-aqueous secondary battery of the present invention, the balance between cycleability and safety is better than before, and a high capacity non- Since it can be set as a water secondary battery, this invention is very useful industrially.

  In the production method of the present invention, a specific element A (B, Al, Ga, In, etc.) is formed on the particle surface of a material that can be doped / undoped with lithium ions (hereinafter sometimes referred to as “core material”). A compound containing one or more elements selected from Si, Ge, Sn, Mg and transition metal elements is deposited.

  As the core material, either a positive electrode or a negative electrode active material may be used, but when the positive electrode active material is used, the positive electrode active material is preferable because the effect of the present invention is large. As the positive electrode active material, for example, a lithium secondary battery Examples of the positive electrode active material include lithium nickelate, lithium cobaltate, and lithium manganate, and lithium nickelate increases the charge / discharge capacity of the non-aqueous secondary battery using the active material of the present invention. ,preferable.

Lithium nickelate has a formula Li _x Ni _{1- y My} O _{2 in} which a part of nickel is replaced with another element by a lithium nickel composite oxide (wherein x and y are 0.9 ≦ x ≦ 1.2, 0 ≦ y ≦ 0.5, and M is one or more metal elements selected from B, Al, Ga, In, Si, Ge, Sn, Mg, and transition metal elements. The compounds shown are included. M in the formula is preferably one or more metal elements selected from B, Al, Mg, Co, Cr, Mn and Fe.

Further, as a core material in the present invention, a formula Li _x Ni _1-z M ² _z O _{2 in} which a part of nickel is substituted with two or more other elements (wherein x and z are 0.9 ≦ x, respectively) ≦ 1.2, 0.3 ≦ z ≦ 0.9, and M ² is two or more metal elements selected from B, Al, Si, Sn, Mg, Mn, Fe, and Co. Mention may be made of the compounds indicated. In order to increase the cycleability and safety of the non-aqueous secondary battery, z is preferably a value in the range of 0.4 to 0.8, more preferably in the range of 0.5 to 0.7. M ² is preferably two or more elements selected from B, Al, Mn, Fe and Co, more preferably two or more elements selected from B, Mn, Fe and Co. More preferably two or more elements selected from Mn, Fe and Co.

  The element A deposited on the particle surface of the core material is one or more elements selected from B, Al, Ga, In, Si, Ge, Sn, Mg, and transition metal elements. One or more selected from Co, Cr, Mn and Fe are preferable, and Al is particularly preferable.

  Examples of the compound containing element A include oxides, hydroxides, oxyhydroxides, carbonates, nitrates, organic acid salts, and mixtures thereof of element A. Among these, oxides, hydroxides, oxyhydroxides, carbonates of these elements A, or mixtures thereof are preferable.

  In the present invention, the compound containing the element A is preferably finer than the particles of the core material in order to more efficiently cover the particle surface of the core material, and the BET ratio of the compound containing the element A The surface area is preferably at least 5 times the BET specific surface area of the core material particles, more preferably at least 20 times.

  The amount of the compound containing the element A is a non-aqueous secondary in which the amount of the element A is usually 0.005 to 0.15 mol part with respect to the core material, and the balance between discharge capacity, cycleability and safety is excellent. Since the active material which gives a battery can be obtained, the quantity from which element A will be 0.02-0.10 mol part with respect to a core material is more preferable.

  The process for producing the adherend by depositing the compound containing the element A on the particle surface of the core material is preferably dry mixing industrially. The dry mixing method is not particularly limited, but the adherend can be produced, for example, simply by putting a predetermined amount of the core material and the compound containing the element A into a container and shaking the mixture. Moreover, it can also be performed by industrially used apparatuses such as V-type, W-type, double-cone type mixers, powder mixers having a screw and stirring blades inside, a ball mill, and a vibration mill.

  At this time, if the mixing is insufficient, the cycleability and safety of the non-aqueous secondary battery produced using the finally obtained active material may be reduced. It is preferable to mix to such an extent that an aggregate cannot be visually confirmed. When at least one mixing process using media is added to the dry mixing process, the mixing efficiency is good, and the compound containing element A can be firmly attached to the particle surface of the core material, resulting in more cycleability and safety. It is preferable because it tends to be an active material for a non-aqueous secondary battery that gives a non-aqueous secondary battery having excellent resistance.

  The adherend thus manufactured is held in an atmosphere containing water so that the weight increase rate of the adherend is in the range of 0.1% by weight to 5.0% by weight. . By setting the weight increase rate within the above range, the obtained non-aqueous secondary battery active material becomes a non-aqueous secondary battery active material that provides a non-aqueous secondary battery excellent in cycle performance and safety. The weight increase rate of the adherend is preferably in the range of 0.3% by weight to 3.0% by weight. The method of measuring the rate of weight increase is not particularly limited. For example, the empty weight of the container filled with the adherend is measured, the adherend is filled, and the total weight before and after holding in the atmosphere is measured. By doing so, the weight increase rate of the adherend can be calculated.

  When the temperature at which the adherend is held in an atmosphere containing water is in the range of 20 ° C. or higher and 90 ° C. or lower and the relative humidity is in the range of 20% or higher and 90% or lower, the non-excellence that is more excellent in cycleability and safety This is preferable because it tends to be an active material for a non-aqueous secondary battery giving a water secondary battery, and the weight increase rate can be easily controlled. A temperature of 30 ° C. to 70 ° C. and a relative humidity of 50% to 80% are further preferable ranges.

  Examples of the method for holding the adherend in an atmosphere containing water include a method in which a container is filled with the adherend and the tray is held in a temperature-controlled and humidity-controlled atmosphere.

  Supplying carbon dioxide gas while holding the adherend is preferable from the viewpoint of shortening the holding time. In particular, if the amount of carbon dioxide in the atmosphere holding the adherend is 0.05 to 50 mg / h / (g-adhesive material), the achievement time of the weight increase rate is short, and the control of the weight increase rate is also compared. It becomes easy and easy. At this time, as a carbon dioxide gas supply method, a gas containing carbon dioxide gas may be continuously supplied while the adherend is held in the atmosphere, and before the adherend is held in the atmosphere, it may be supplied in advance. Carbon dioxide gas may be introduced into the atmosphere. Examples of the gas containing carbon dioxide include pure carbon dioxide, inert gas such as air, nitrogen, oxygen, and argon, and gas obtained by diluting carbon dioxide with a mixed gas thereof.

  On the other hand, if the amount of carbon dioxide gas is larger than 50 mg / h / (g-adhering material), the time to reach a predetermined weight increase becomes too short, and the weight increase rate control tends to be difficult. It is a further preferred embodiment in the present invention that the amount of carbon dioxide gas is 0.1 to 10 mg / h / (g-adhering material).

In the production method of the present invention, an active material for a non-aqueous secondary battery is produced by firing the adherend holding material obtained by holding the adherend in an atmosphere containing water as described above. .
As firing conditions, a firing temperature of 600 ° C. or higher and a firing time of 30 minutes or longer are preferable. When the firing temperature is less than 600 ° C. or the firing time is less than 30 minutes, the element A deposited on the core material particles tends not to adhere sufficiently to the particle surface of the core material. Note that the firing temperature and time here are the maximum temperature and holding time at the maximum temperature in the temperature raising program, respectively. In the case of temperature, if there is a difference between the program temperature and the actual temperature, the actual temperature will be Use the converted temperature.

  Here, the core material particles are preferably produced by a process including at least one firing, and in that case, the firing of the adherend holding material using the core material is performed by the core material particles. The temperature is not particularly limited as long as the crystal structure is not destroyed and the holding time. At this time, either the temperature or holding time in the firing of the adherent holding material using the core material is a range that does not exceed the temperature or holding time in the firing step of the particle production of the core material, This is preferable because it tends to be an active material for a non-aqueous secondary battery that provides a non-aqueous secondary battery with an excellent balance between cycle performance and safety.

  Examples of the firing atmosphere include air, oxygen, nitrogen, carbon dioxide, water vapor, nitrogen oxides, hydrogen sulfide, or a mixed gas thereof, or under reduced pressure, but high concentration during firing of lithium nickelate or the like When a core material made of a material that requires an oxygen atmosphere is used, firing is preferably performed in an atmosphere having an oxygen concentration of 90% by volume or more so that the crystallinity of the core material does not decrease.

  In addition, when the BET specific surface area of the active material obtained after firing is 0.7 to 2 times the BET specific surface area of the core material particles, the finally obtained active material for a non-aqueous secondary battery has a capacity. The non-aqueous secondary battery is excellent in cycle performance and safety, and is preferably 0.8 times or more and 1.2 times or less.

Further, the active material for a non-aqueous secondary battery of the present invention has an element A (B, Al, Ga, In, Si, Ge, Sn, Mg, and transition on the particle surface of a material that can be doped / undoped with lithium ions. An active material for a non-aqueous secondary battery produced by firing an adherend containing a compound containing one or more elements selected from metal elements), wherein the active material and an alkali When the solution is mixed, the weight ratio (W ₁ ) of the element A extracted from the active material into the alkaline solution is based on the weight ratio (W ₂ ) of the element A contained in the active material before mixing. And 3.0% or less.

More preferably, one or more elements selected from the elements A (B, Al, Ga, In, Si, Ge, Sn, Mg and transition metal elements) are formed on the particle surface of the material that can be doped / undoped with lithium ions. The adhering material to which the compound containing the element) is applied is adjusted so that the weight increase rate of the adhering material is in the range of 0.1 wt% or more and 5.0 wt% or less in the atmosphere containing water. An active material for a non-aqueous secondary battery produced by firing and holding this, and when the active material and an alkaline solution are mixed, the element A extracted from the active material into the alkaline solution The active part for a non-aqueous secondary battery, wherein the weight ratio (W ₁ ) is 3.0% or less with respect to the weight ratio (W ₂ ) of the element A contained in the active material before mixing. It is a substance.

The weight ratio (W ₁ ) of the element A extracted from the active material into the alkaline solution is 3.0% or less with respect to the weight ratio (W ₂ ) of the element A contained in the active material before mixing. Thus, an active material for a non-aqueous secondary battery that provides a non-aqueous secondary battery with an excellent balance between cycleability and safety can be obtained. In order to obtain an active material for a non-aqueous secondary battery that gives a non-aqueous secondary battery with a better balance between cycleability and safety, the weight ratio of the element A extracted from the active material into the alkaline solution ( W ₁ ) is preferably 2% or less, more preferably 1% or less with respect to the weight ratio (W ₂ ) of element A contained in the active material before mixing, It is still more preferable to set it as% or less.

  As the alkaline solution used in the present invention, an aqueous solution or aqueous ammonia in which a hydroxide or carbonate containing one or more alkali metals selected from Li, Na, and K can be used. It is preferable to use the same alkali metal as the alkali metal used for the core material of the battery active material. By using an aqueous solution containing the same alkali metal as the alkali metal used for the core material as the alkali solution, dissolution of the alkali metal of the active material for a non-aqueous secondary battery tends to be suppressed.

  In the present invention, as a method of mixing the active material and the alkaline solution, any method may be used as long as the active material and the alkaline solution are brought into contact with each other. You may mix by shaking. Moreover, you may heat when mixing an active material and an alkaline solution.

In the present invention, the active material (the weight is set to W _S.) And a mixture of an alkali solution, when extracting the element A in the alkaline solution from the active material, the amount of the element A extracted over time i.e. When the weight of the element A in the alkaline solution increases and a certain time (extraction time T ₁ ) elapses, the weight of the element A becomes constant. When analyzing the weight of the element A, the analysis is performed using the alkaline solution after the weight of the element A in the alkaline solution becomes constant. When mixing the active material and the alkaline solution, the extraction time of element A (extraction time T ₁ ) can be shortened by heating or shaking.

In the present invention, the amount of the element A to be extracted, that is, the weight of the element A in the alkaline solution is described as inductively coupled plasma emission spectrometry (hereinafter referred to as ICP-AES), considering that it is suitable for trace analysis. ). That is, using the alkaline solution after the weight of the element A in the alkaline solution becomes constant, the value obtained by measurement using ICP-AES is divided by W _s , and the alkaline solution is separated from the active material. The weight ratio (W ₁ ) of the element A extracted in As the weight percentage of the element A contained in the mixture before the active material (W _2), an active material was W _S weighed, dissolved active material by contacting the active substance and an acidic aqueous solution such as hydrochloric acid The value obtained by measurement using ICP-AES is divided by W _s using the aqueous solution obtained, and the weight ratio (W ₂ ) of element A contained in the active material before mixing is obtained. When the value obtained by dividing (W ₁ ) by (W ₂ ) and further multiplying by 100, that is, the value of W ₁ / W ₂ × 100 (%) is 3.0 or less, the balance between cycleability and safety is achieved. Therefore, it is possible to obtain an active material for a non-aqueous secondary battery that provides a non-aqueous secondary battery excellent in performance. Further, the value of W ₁ / W ₂ × 100 (%) is preferably 2 or less, more preferably 1 or less, and even more preferably 0.7 or less. In the present invention, the value of W ₁ / W ₂ × 100 (%) may be called the element A elution rate.

Further, as described above, the weight ratio (W ₁ ) of the element A contained in the active material is obtained, the active material and the alkali solution are mixed, and the element extracted from the active material into the alkaline solution The evaluation method of the active material for a non-aqueous secondary battery for obtaining the weight ratio (W ₂ ) of A is based on the element A (B, Al, Ga, In, Si) on the particle surface of a material capable of doping and dedoping lithium ions. , Ge, Sn, Mg and one or more elements selected from transition metal elements), an active material for a non-aqueous secondary battery manufactured by firing an adhering material on which a compound containing an adhering material is applied. As an evaluation method, it is simple and very useful.

  The non-aqueous secondary battery active material obtained by the production method of the present invention or the non-aqueous secondary battery active material of the present invention is a non-aqueous secondary battery that provides a non-aqueous secondary battery excellent in cycleability and safety. It becomes an active material for batteries. As a non-aqueous secondary battery here, the lithium secondary battery shown below can be mentioned, for example.

  A lithium secondary battery is given as an example of a non-aqueous secondary battery, and a method for producing a lithium secondary battery using the active material obtained by the present invention as a positive electrode active material will be described below. The lithium secondary battery includes a positive electrode composed of a positive electrode mixture and a positive electrode current collector, a negative electrode composed of a negative electrode material and a negative electrode current collector, an electrolyte, an organic solvent, and a separator.

  Examples of the positive electrode material mixture include a positive electrode active material obtained by the present invention, a carbonaceous material as a conductive material, a thermoplastic resin as a binder, and the like. Examples of the carbonaceous material include natural graphite, artificial graphite, cokes, and carbon black. As the conductive material, each may be used alone, for example, artificial graphite and carbon black may be mixed and used.

Examples of the thermoplastic resin include polyvinylidene fluoride (hereinafter sometimes referred to as PVDF), polytetrafluoroethylene (hereinafter sometimes referred to as PTFE), tetrafluoroethylene, hexafluoropropylene, and vinylidene fluoride. Examples thereof include a copolymer, a hexafluoropropylene / vinylidene fluoride copolymer, and a tetrafluoroethylene / perfluorovinyl ether copolymer. These may be used alone or in combination of two or more. Note that these binders may be those dissolved in an organic solvent in which the binder is soluble, such as 1-methyl-2-pyrrolidone (hereinafter sometimes referred to as NMP).
Further, a fluororesin and a polyolefin resin are used as binders, so that the ratio of the fluororesin in the positive electrode mixture is 1 to 10% by weight and the ratio of the polyolefin resin is 0.1 to 2% by weight. Use in combination with the positive electrode active material of the invention is preferable because it is excellent in binding property with the current collector and can further improve the safety of the lithium secondary battery against external heating as represented by the heating test.

  As the positive electrode current collector, Al, Ni, stainless steel, or the like can be used, but Al is preferable because it is easily processed into a thin film and is inexpensive. Examples of the method of supporting the positive electrode mixture on the positive electrode current collector include a method of pressure molding, or a method of pasting using a solvent or the like, and applying and drying on the current collector and then fixing. .

  As a negative electrode material of the lithium secondary battery of the present invention, for example, a lithium metal, a lithium alloy, or a material that can be doped / undoped with lithium ions can be used. Materials that can be doped / undoped with lithium ions include carbonaceous materials such as natural graphite, artificial graphite, cokes, carbon black, pyrolytic carbons, carbon fibers, and fired organic polymer compounds; lower potential than the positive electrode And chalcogen compounds such as oxides and sulfides for doping and dedoping lithium ions. As a carbonaceous material, graphite materials such as natural graphite and artificial graphite are mainly used in that a lithium secondary battery having a large energy density is obtained when combined with a positive electrode because of high potential flatness and low average discharge potential. A carbonaceous material as a component is preferable.

  Also, when used in combination with a liquid electrolyte, when the liquid electrolyte does not contain ethylene carbonate, the use of a negative electrode containing polyethylene carbonate improves the cycle characteristics and large current discharge characteristics of the lithium secondary battery. preferable.

  The shape of the carbonaceous material may be, for example, a flake shape such as natural graphite, a spherical shape such as mesocarbon microbeads, a fibrous shape such as graphitized carbon fiber, or an aggregate of fine powder. Then, a thermoplastic resin as a binder can be added. Examples of the thermoplastic resin include PVDF, polyethylene, and polypropylene.

  Examples of the chalcogen compounds such as oxides and sulfides used as the negative electrode material include crystalline materials mainly composed of Group 13, 14 and 15 elements of the periodic table, such as amorphous compounds mainly composed of tin compounds. Or an amorphous oxide etc. are mentioned. Also in these cases, a carbonaceous material as a conductive material and a thermoplastic resin as a binder can be added as necessary.

  As the negative electrode current collector, Cu, Ni, stainless steel, or the like can be used. In particular, in a lithium secondary battery, Cu is preferable because it is difficult to form an alloy with lithium and it can be easily processed into a thin film. The negative electrode current collector is loaded with a mixture containing the negative electrode active material by pressure molding, or pasted using a solvent, and then applied to the current collector and then fixed by pressing, etc. A method is mentioned.

  As a separator used in the lithium secondary battery of the present invention, for example, a material made of an olefin resin such as fluororesin, polyethylene, or polypropylene, nylon, aromatic aramid, or the like and having a form such as porous, non-woven fabric, or woven fabric is used. it can. The thickness of the separator is preferably as thin as possible as long as the mechanical strength is maintained in that the volume energy density of the battery is increased and the internal resistance is reduced, and is preferably about 10 to 200 μm.

As the electrolyte used in the lithium secondary battery which is one embodiment of the present invention, for example, a known one selected from a non-aqueous electrolyte solution in which a lithium salt is dissolved in an organic solvent or a solid electrolyte is used. Can do. Examples of the lithium salt include LiClO ₄ , LiPF ₆ , LiAsF ₆ , LiSbF ₆ , LiBF ₄ , LiCF ₃ SO ₃ , LiN (CF ₃ SO ₂ ) ₂ , LiC (CF ₃ SO ₂ ) ₃ , Li ₂ B ₁₀ Cl ₁₀ , One or a mixture of two or more of lower aliphatic carboxylic acid lithium salts, LiAlCl ₄ , LiB (C ₂ O ₄ ) _2, etc. may be mentioned.

  Examples of the organic solvent used in the lithium secondary battery which is one embodiment of the present invention include propylene carbonate, ethylene carbonate, dimethyl carbonate, diethyl carbonate, ethyl methyl carbonate, 4-trifluoromethyl-1,3-dioxolane- Carbonates such as 2-one and 1,2-di (methoxycarbonyloxy) ethane; 1,2-dimethoxyethane, 1,3-dimethoxypropane, pentafluoropropyl methyl ether, 2,2,3,3-tetrafluoro Ethers such as propyldifluoromethyl ether, tetrahydrofuran, 2-methyltetrahydrofuran; esters such as methyl formate, methyl acetate, and γ-butyrolactone; nitriles such as acetonitrile and butyronitrile; N, N-dimethylform Amides such as amide, N, N-dimethylacetamide; carbamates such as 3-methyl-2-oxazolidone; sulfur-containing compounds such as sulfolane, dimethyl sulfoxide, 1,3-propane sultone; or the above organic solvents Although the thing which introduce | transduced the fluorine substituent can be used, normally 2 or more types of these are mixed and used. Among these, a mixed solvent containing carbonates is preferable, and a mixed solvent of cyclic carbonate and acyclic carbonate or cyclic carbonate and ether is more preferable.

  As a mixed solvent of cyclic carbonate and acyclic carbonate, a lithium secondary battery having a wide operating temperature range and excellent load characteristics is obtained, and it is difficult even when a graphite material such as natural graphite or artificial graphite is used as the negative electrode active material. In view of decomposability, a mixed solvent containing ethylene carbonate, dimethyl carbonate and ethyl methyl carbonate is preferred.

Further, a layered rock-salt crystal structure obtained positive electrode active material containing Li and Ni and / or Co by the present invention, when further containing Al, in that particularly excellent safety improving effect is obtained, LiPF ₆ It is preferable to use an electrolyte containing a lithium salt such as fluorine and / or an organic solvent having a fluorine substituent. A mixed solvent containing ethers having fluorine substituents, such as pentafluoropropyl methyl ether and 2,2,3,3-tetrafluoropropyl difluoromethyl ether, and dimethyl carbonate is a lithium secondary battery having excellent large current discharge characteristics Is more preferable.

As the solid electrolyte, for example, a polymer electrolyte such as a polyethylene oxide polymer compound, a polymer compound including at least one of a polyorganosiloxane chain or a polyoxyalkylene chain can be used. Moreover, what is called a gel type which hold | maintained the nonaqueous electrolyte solution in the polymer | macromolecule can also be used. Further, from the viewpoint of enhancing the safety of the lithium secondary battery, sulfides such as Li ₂ S—SiS ₂ , Li ₂ S—GeS ₂ , Li ₂ S—P ₂ S ₅ , Li ₂ S—B ₂ S ₃ It is also possible to use a system electrolyte or an inorganic compound electrolyte containing a sulfide such as Li ₂ S—SiS ₂ —Li ₃ PO ₄ or Li ₂ S—SiS ₂ —Li ₂ SO ₄ .

The shape of the non-aqueous secondary battery of the present invention is not particularly limited, and may be any of a paper type, a coin type, a cylindrical type, a square type, and the like.
Moreover, you may use the bag-shaped package which consists of a laminated sheet etc. which contain aluminum, without using the metal hard case which serves as a negative electrode or a positive electrode terminal as an exterior.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited at all by these. Unless otherwise specified, the electrodes for the charge / discharge test and the flat battery were produced by the following method.

  A 1-methyl-2-pyrrolidone (hereinafter, sometimes referred to as NMP) solution of PVDF as a binder is mixed with a mixture of compound particles capable of doping and dedoping alkali metal ions as an active material and conductive material acetylene black. Material: Conductive material: Binder = 86: 10: 4 (weight ratio) In addition to kneading and kneading to make a paste of the positive electrode mixture, the paste was applied to a # 100 stainless steel mesh to be a current collector Then, vacuum drying was performed at 150 ° C. for 8 hours to obtain a positive electrode.

On the obtained positive electrode, ethylene carbonate (hereinafter may be referred to as EC), dimethyl carbonate (hereinafter may be referred to as DMC) and ethyl methyl carbonate (hereinafter may be referred to as EMC) as electrolytes. A solution obtained by dissolving LiPF ₆ in a 30:35:35 vol% liquid mixture so as to be 1.0 mol / liter (hereinafter sometimes referred to as LiPF ₆ / EC + DMC + EMC), a polypropylene porous membrane as a separator, A flat battery was prepared by combining metallic lithium as a counter electrode (negative electrode).

Example 1
(1) Manufacture of core material particles Lithium hydroxide (LiOH · H ₂ O: manufactured by Honjo Chemical Co., Ltd., pulverized product average particle size: 10 to 25 μm) and nickel hydroxide (Ni (OH) ₂ : manufactured by Tanaka Chemical Laboratory) The product name is nickel hydroxide D, the average particle size is about 20 μm), and cobalt hydroxide (Co (OH) ₂ : Tanaka Chemical Laboratory, previously dried in the air at 150 ° C. for 12 hours, the product name is hydroxylated. Cobalt, average particle diameter of 2 to 3 μm) was weighed so that the atomic ratio of each metal was the following molar ratio, and mixed using a V-type mixer to obtain a raw material mixed powder.
Li: Ni: Co = 1.05: 0.85: 0.15
After drying the obtained raw material mixed powder at 120 ° C. for 12 hours, using a dynamic mill (MYD-5XA type, manufactured by Mitsui Mining Co., Ltd.), pulverized and mixed under the following conditions, Obtained.
Grinding media: 5mmφ high alumina (6.1kg)
Number of rotations of agitator shaft: 650 rpm
Supply amount of dry raw material mixed powder: 10.3 kg / h
The pulverized raw material powder was filled into an alumina sheath and fired at 720 ° C. for 15 hours in an oxygen stream to obtain a lump. This lump was pulverized with a dry ball mill using a 15 mmφ nylon-coated steel ball as a pulverization medium, and the volume-based average particle size was 5.5 μm (laser diffraction particle size distribution analyzer SALD-1100 (Shimadzu Corporation). The core material particle C1 was obtained by pulverization until measurement). The obtained core material particle C1 was confirmed to have an α-NaFeO ₂ type structure by powder X-ray diffraction. Moreover, it was 0.9 m < ² > / g when the BET specific surface area of the particle | grains C1 of the core material was measured by the BET single point method with the BET specific surface area measuring apparatus Macsorb HM Model-1208 type | mold (made by Mountec Co., Ltd.).

(2) Production method of adherend material 900 g of the obtained core material particle C1 and 37.4 g of aluminum oxide (manufactured by Nippon Aerosil Co., Ltd., primary particle diameter 13 nm, product name is alumina C) (core material particle C1 (Added so as to be 0.08 mol part of Al element with respect to (Ni + Co) in the inside) in a polyethylene pot with an internal volume of 5 L, and using 4.2 kg of 15 mmφ nylon-coated steel balls as a medium at 80 rpm A dry ball mill was mixed for 30 minutes to obtain an adherend H1. In addition, when the BET specific surface area of the aluminum oxide used here was measured, it was 113 m ² / g, and the ratio of the BET specific surface area of the aluminum oxide to the BET specific surface area of the particles of the core material was calculated to be 126.

(3) Treatment of adherend material A constant temperature and humidity chamber in which 180 g of the obtained adherend material H1 was filled into a stainless steel tray (400 × 240 × 66 mmt) and temperature-controlled and humidity-controlled at a temperature of 30 ° C. and a relative humidity of 70%. Set. At this time, carbon dioxide gas was not introduced into the system, and after holding for 17.5 hours, the stainless steel tray was taken out of the constant temperature and humidity chamber to obtain an adherent holding material K1 having a weight increase rate of 1.5% by weight. The adherend holding material K1 was fired at 720 ° C. for 1 hour in an oxygen stream to obtain a powder S1. It was 0.9 m < ² > / g when the BET specific surface area of powder S1 was measured. The BET specific surface area ratio with respect to the particles C1 of the core material of the powder S1 was calculated to be 1.0.

(4) Charging / discharging performance evaluation when used as a positive electrode active material of a lithium secondary battery A flat battery was prepared using the obtained powder S1, and charging / discharging by constant current constant voltage charging and constant current discharging under the following conditions. The test was conducted.
Maximum charging voltage: 4.3V
Charging current: 0.7 mA / cm ²
Charging time: 8 hours (only the first two charges are charged for 12 hours)
Discharge minimum voltage: 3.0V
Discharge current: 0.7 mA / cm ²
The initial discharge capacity was 186 mAh / g, the (discharge capacity after 20 cycles) / (discharge capacity after 10 cycles) ratio (cycle characteristics) was 96.4%, indicating high capacity and high cycle characteristics.

(5) Evaluation of safety In order to evaluate safety by examining the reaction behavior when heated in a deep charged state, sealed DSC measurement was performed according to the following procedure. First, a flat battery was produced using a powder S1 in combination with metallic lithium, and was subjected to constant current and constant voltage charging under the following conditions.
Maximum charging voltage: 4.3V
Charging current: 0.5 mA / cm ²
Charging time: 20 hours The charged battery is disassembled in a glove box in an argon atmosphere, the positive electrode is taken out, washed with DMC, dried, and then the positive electrode mixture is scraped off from the current collector to obtain a charged positive electrode mixture. It was. Subsequently, 0.8 mg of the charge mixture was weighed into a stainless steel sealed cell, and further LiPF ₆ was added to the EC: VC: DMC: EMC = 12: 3: 20: 65 volume% mixture as a nonaqueous electrolyte solution. 1.5 microliters of the solution dissolved so as to be 1 mol / liter was injected so that the charged positive electrode mixture was wet, and sealed with a jig.
Subsequently, the sealed stainless steel cell was set in a DSC220 type (manufactured by Seiko Denshi Kogyo Co., Ltd.), and measurement was performed at a temperature increase rate of 10 ° C./min. The calorific value was measured and found to be 490 mJ / mg.

Example 2
(1) Manufacture of core material particles Lithium hydroxide (LiOH.H ₂ O; manufactured by Honjo Chemical Co., Ltd., pulverized product, average particle size of 10 to 25 μm) and nickel hydroxide (Ni (OH) ₂ ; Kansai Catalyst Chemical Co., Ltd. Made by company, product name is nickel hydroxide No. 3) and cobalt oxide (Co ₃ O ₄ ; manufactured by Shodo Chemical Industry Co., Ltd., product name is cobalt oxide (HCO)) The raw material mixed powder was obtained by weighing so that it might become ratio, and mixing using a Laedige mixer (the Matsubo Co., Ltd. make, M-20 type | mold).
Li: Ni: Co = 1.05: 0.85: 0.15

The obtained raw material mixed powder was dried at 120 ° C. for 10 hours, and then pulverized and mixed under the following conditions using a dynamic mill (MYD-5XA type, manufactured by Mitsui Mining Co., Ltd.).
Grinding media: 5mmφ high alumina (6.1kg)
Number of rotations of agitator shaft: 650 rpm
Supply amount of dry raw material mixed powder: 12.0kg / h

The pulverized raw material powder was fired and pulverized under the same conditions as in Example 1 (1), and after producing core material particles C2 (BET specific surface area: 1.0 m ² / g), the same as in Example 1 (2) Thus, an adherend H2 was obtained. The ratio of the BET specific surface area of aluminum oxide to the BET specific surface area of the core material particles was calculated to be 113.

After 720 g of the obtained adherend H2 was divided into 4 stainless trays (400 × 240 × 66 mmt) and filled (each stainless steel tray was filled with 180 g), this stainless steel tray was adjusted to a temperature of 50 ° C. and a relative humidity of 60%. It was set in a temperature and humidity controlled constant temperature and humidity chamber (PR-2K [H], internal volume 225 L). At this time, carbon dioxide gas was introduced into the system at 19 ml / min (20 ° C.). After holding for 3 hours, the stainless steel tray was taken out of the constant temperature and humidity chamber to obtain an adherent holding material K2 having a weight increase rate of 1.5% by weight. The carbon dioxide originally present in the system was calculated to be 0.1 g when the carbon dioxide concentration in the atmosphere was 0.03% by volume. The amount of carbon dioxide introduced was calculated to be 2.1 g / h. Therefore, the amount of carbon dioxide gas with respect to the adherend per unit weight was calculated as 3.0 mg / h / (g-adhesive).
The adherend holding material K2 was baked at 725 ° C. for 1 hour in an oxygen stream to obtain a powder S2. It was 1.0 m < ² > / g when the BET specific surface area of powder S2 was measured. The BET specific surface area ratio of the core material of the powder S2 to the particle C2 was calculated to be 1.0.

Using the powder S2 as the positive electrode active material, the charge / discharge characteristics were measured under the same conditions as in Example 1. The initial discharge capacity was 186 mAh / g, (discharge capacity after 20 cycles) / (discharge capacity after 10 cycles). ) Ratio (cycleability) was 96.2%, indicating high capacity and high cycleability.
In addition, when the DSC calorific value was measured under the same conditions as in Example 1 using Powder S2 as the positive electrode active material, it was 470 mJ / mg.

Example 3
After 360 g of the adherend H2 obtained in Example 2 was divided into two stainless steel trays (400 × 240 × 66 mmt) (each stainless steel tray was filled with 180 g), the stainless steel tray was heated at a temperature of 50 ° C. It was set in a constant temperature and humidity chamber that was adjusted to 60% humidity. At this time, carbon dioxide gas was introduced into the system at 8.4 ml / min (20 ° C.). After 2 hours, the stainless steel tray was taken out of the thermostatic / humidifier to obtain an adherent holding material K3 having a weight increase rate of 1.0% by weight. As in Example 2, the amount of carbon dioxide gas with respect to the adherend per unit weight was calculated and found to be 2.7 mg / h / (g-adhesive).
Thereafter, the adherend holding material K3 was fired under the same conditions as in Example 2 to obtain a powder S3. The BET specific surface area of the powder S3 was measured and found to be 1.0 m ² / g. The BET specific surface area ratio with respect to the particles C2 of the core material of the powder S3 was calculated to be 1.0.

When the charge / discharge characteristics were measured under the same conditions as in Example 1 using the powder S3 as the positive electrode active material, the initial discharge capacity was 185 mAh / g, (discharge capacity after 20 cycles) / (discharge capacity after 10 cycles). ) Ratio (cycleability) was 96.3%, indicating high capacity and high cycleability.
Moreover, when DSC heat generation amount was measured on the same conditions as Example 1 using powder S3 for a positive electrode active material, it was 490 mJ / mg.

Example 4
After 360 g of the adherend H2 obtained in Example 2 was divided into two stainless steel trays (400 × 240 × 66 mmt) (each stainless steel tray was filled with 180 g), the stainless steel tray was heated at a temperature of 50 ° C. It was set in a constant temperature and humidity chamber that was adjusted to 60% humidity. At this time, carbon dioxide gas was introduced into the system at 8.4 ml / min (20 ° C.). After 5 hours, the stainless steel tray was taken out of the thermostatic / humidifier, and an adherent holding material K4 having a weight increase rate of 2.0% by weight was obtained. Similarly to Example 2, the amount of carbon dioxide gas with respect to the adherend per unit weight was calculated and found to be 2.6 mg / h / (g-adhesive).
Thereafter, the adherend holding material K4 was fired under the same conditions as in Example 2 to obtain a powder S4. It was 1.0 m < ² > / g when the BET specific surface area of powder S4 was measured. The BET specific surface area ratio with respect to the particles C2 of the core material of the powder S4 was calculated to be 1.0.

Using the powder S4 as the positive electrode active material, the charge / discharge characteristics were measured under the same conditions as in Example 1. The initial discharge capacity was 186 mAh / g, (discharge capacity after 20 cycles) / (discharge capacity after 10 cycles). ) Ratio (cycleability) was 96.2%, indicating high capacity and high cycleability.
Moreover, when DSC heat generation amount was measured on the same conditions as Example 1 using powder S4 for a positive electrode active material, it was 470 mJ / mg.

Comparative Example 1
A flat plate battery was produced using the core material particle C1 as a positive electrode active material, and a charge / discharge test by constant current and constant voltage charge and constant current discharge was performed under the following conditions.
Maximum charging voltage: 4.3V
Charging current: 0.8 mA / cm ²
Charging time: 8 hours (only the first two charges are charged for 12 hours)
Discharge minimum voltage: 3.0V
Discharge current: 0.8 mA / cm ²
The initial discharge capacity is 203 mAh / g, the (discharge capacity after 20 cycles) / (discharge capacity after 10 cycles) ratio (cycle characteristics) is 93.5%, the discharge capacity is high, but the cycle characteristics are slightly inferior. It was a result.
Further, when the DSC heat generation amount was measured under the same conditions as in Example 1 using the core material particle C1 as the positive electrode active material, it was 650 mJ / mg, which was larger than that in Example 1.

Comparative Example 2
In Example 1, the obtained adherend H1 was baked in the same manner as in Example 1 by omitting the holding step in an atmosphere containing water to obtain a powder S5. It was 1.1 m < ² > / g when the BET specific surface area of powder S5 was measured. The BET specific surface area ratio with respect to the particle C1 of the core material of the powder S5 was calculated to be 1.1.

Using the obtained powder S5 as a positive electrode active material, the charge / discharge characteristics were measured under the same conditions as in Example 1. As a result, the initial discharge capacity was 186 mAh / g, (discharge capacity after 20 cycles) / (after 10 cycles). The discharge capacity) ratio (cycleability) was 96.5%, indicating high capacity and high cycleability.
However, when the DSC calorific value was measured under the same conditions as in Example 1 using Powder S5 as the positive electrode active material, it was 600 mJ / mg, which was larger than Example 1.

Comparative Example 3
When the charge / discharge characteristics were measured under the same conditions as in Comparative Example 1 using the core material particle C2 as the positive electrode active material, the initial discharge capacity was 206 mAh / g, (discharge capacity after 20 cycles) / (after 10 cycles). The discharge capacity) ratio (cycle property) was 94.6%, and the discharge capacity was high, but the cycle characteristics were slightly inferior.
Further, when the DSC calorific value was measured under the same conditions as in Example 1 using the core material particle C2 as the positive electrode active material, it was 570 mJ / mg, which was larger than Example 2.

Comparative Example 4
In Example 2, the obtained adherend H2 was baked in the same manner as in Example 3 by omitting the holding step in an atmosphere containing water to obtain powder S6. It was 1.1 m < ² > / g when the BET specific surface area of powder S6 was measured. The BET specific surface area ratio with respect to the particles C2 of the core material of the powder S6 was calculated to be 1.1.
Using the obtained powder S6 as the positive electrode active material, the charge / discharge characteristics were measured under the same conditions as in Example 1. As a result, the initial discharge capacity was 187 mAh / g, (discharge capacity after 20 cycles) / (after 10 cycles). The discharge capacity) ratio (cycleability) was 96.4%, indicating high capacity and high cycleability.
However, when the DSC calorific value was measured under the same conditions as in Example 1 using Powder S6 as the positive electrode active material, it was 600 mJ / mg, which was larger than Example 2.

Example 5
(1) Manufacture of core material particles Lithium carbonate (Li ₂ CO ₃ : manufactured by Honjo Chemical Co., Ltd.), nickel hydroxide (Ni (OH) ₂ : manufactured by Kansai Catalysts Chemical Co., Ltd.) and manganese oxide (MnO ₂ : high purity) Chemical Co., Ltd.), cobalt tetroxide (Co ₃ O ₄ : manufactured by Shodo Chemical Industry Co., Ltd.) and boric acid (H ₃ BO ₃ : manufactured by Yoneyama Chemical Co., Ltd.) The raw material mixed powder was obtained by measuring so that it might become ratio, and mixing using the Laedige mixer (Chuo Kiko Co., Ltd. make, M-20).
Li: Ni: Mn: Co: B = 1.04: 0.34: 0.42: 0.2: 0.03

The obtained raw material mixed powder was finely pulverized and mixed under the following conditions using a ball mill mixer to obtain a pulverized raw material powder.
Grinding media: 15mmφ alumina balls (5.8kg)
Ball mill rotation speed: 80 rpm
Ball mill volume: 5L
The pulverized raw material powder was filled in an alumina sheath and fired at 1040 ° C. for 4 hours in an air atmosphere to obtain a lump. This lump was pulverized with a dry ball mill under the same conditions as the raw material pulverization using 15 mmφ alumina balls as a pulverization medium, and the volume-based average particle diameter was about 3 μm (laser diffraction particle size distribution analyzer, Malvern Mastersizer). 2000, measured by Malvern Instruments Ltd.) to obtain core material particles C7. The obtained core material particles C7 were confirmed to have an α-NaFeO ₂ type structure by powder X-ray diffraction. Moreover, it was 1.6 m < ² > / g when the BET specific surface area of particle | grains C7 of the core material was measured with the BET specific surface area measuring apparatus Macsorb HM Model-1208 type | mold (made by Mountec Co., Ltd.) by the BET single point method.

(2) Manufacturing method of adherend material 3.0 g of core material particles C7 obtained and 0.0639 g of aluminum oxide (manufactured by Nippon Aerosil Co., Ltd., primary particle diameter 13 nm, product name is alumina C) (core of C7) (Added so as to be 0.04 mol part of Al element with respect to 1 mol part of the material particles) was mixed in an agate mortar for 5 minutes to obtain an adherend H7. The ratio of the BET specific surface area of aluminum oxide to the BET specific surface area of the core material particles was calculated to be 70.6.

(3) Treatment of adherend material A constant temperature and humidity chamber in which 20 g of the obtained adherend material H7 was filled in a stainless steel tray (400 × 240 × 66 mmt) and temperature-controlled and humidity-controlled at a temperature of 50 ° C. and a relative humidity of 60%. Set. At this time, carbon dioxide gas was introduced into the system at 1.0 ml / min (20 ° C.). Two hours later, the stainless steel tray was taken out of the thermostatic / humidifier, and an adherent holding material K7 having a weight increase rate of 1.2% by weight was obtained. As in Example 2, the amount of carbon dioxide gas with respect to the adherend per unit weight was calculated and found to be 5.9 mg / h / (g-adhesive). The adherend holding material K7 was fired at 725 ° C. for 1 hour in an air atmosphere to obtain a powder S7. It was 0.6 m < ² > / g when the BET specific surface area of powder S7 was measured. The BET specific surface area ratio of the core material of the powder S7 to the particle C7 was calculated to be 0.38.

The charge and discharge characteristics were measured under the same conditions as in Example 1 except that the powder S7 was used as the positive electrode active material, the charge current and discharge current were changed to 0.6 mA / cm ² , and the charge time was changed to 8 hours. The discharge capacity was 155 mAh / g, the (discharge capacity after 20 cycles) / (discharge capacity after 10 cycles) ratio (cycleability) was 99.9%, indicating high capacity and high cycleability.
Further, the DSC calorific value was measured under the same conditions as in Example 1 except that the powder S7 was used as the positive electrode active material and the charging current and discharging current were changed to 0.4 mA / cm ² , and it was 360 mJ / mg. It was.

Comparative Example 5
When the charge / discharge characteristics were measured under the same conditions as in Example 5 using the core material particle C7 in Example 5 as the positive electrode active material, the initial discharge capacity was 162 mAh / g, (discharge capacity after 20 cycles) / The (discharge capacity after 10 cycles) ratio (cycle property) was 96.3%.
Further, when the DSC calorific value was measured under the same conditions as in Example 5 using Core Material Particle C7 as the positive electrode active material, it was 490 mJ / mg, which was larger than Example 5.

Example 6
(1) Manufacture of core material particles Lithium hydroxide (LiOH.H ₂ O: manufactured by Honjo Chemical Co., Ltd., pulverized product average particle size: 10 to 25 μm) and nickel hydroxide (Ni (OH) ₂ : manufactured by Kansai Catalyst Co., Ltd.) The product name is nickel hydroxide No. 3) and cobalt oxide (Co ₃ O ₄ ; manufactured by Shodo Chemical Industry Co., Ltd., product name cobalt oxide (HCO)). The raw material mixed powder was obtained by weighing and mixing using a V-type mixer.
Li: Ni: Co = 1.05: 0.85: 0.15
After the obtained raw material mixed powder was dried at 120 ° C. for 10 hours, it was pulverized and mixed under the following conditions using a dynamic mill (manufactured by Mitsui Mining Co., Ltd., MYD-5XA type). Obtained.
Grinding media: 5mmφ high alumina (6.1kg)
Number of rotations of agitator shaft: 650 rpm
Supply amount of dry raw material mixed powder: 12.0kg / h
The pulverized raw material powder was filled into an alumina sheath and fired at 730 ° C. for 15 hours in an oxygen stream to obtain a lump. This lump was pulverized with a dry ball mill using a 15 mmφ nylon-coated steel ball as a pulverization medium, and the volume-based average particle size was 5.5 μm (laser diffraction particle size distribution analyzer SALD-1100 (Shimadzu Corporation). The core material particles C8 were obtained by pulverization until measurement). The obtained core material particle C8 was confirmed to have an α-NaFeO ₂ type structure by powder X-ray diffraction.

(2) Production method of adherend material 1000 g of core material particles C8 obtained and 41.8 g of aluminum oxide (manufactured by Nippon Aerosil Co., Ltd., primary particle size 13 nm, product name is alumina C) (core material particles C8 (Added so as to be 0.08 mol part of Al element with respect to (Ni + Co) in the inside) in a polyethylene pot with an internal volume of 5 L, and using 4.2 kg of 15 mmφ nylon-coated steel balls as a medium at 80 rpm A dry ball mill was mixed for 30 minutes to obtain an adherend H8.

(3) Treatment of adherend A constant temperature and humidity chamber in which 200 g of the obtained adherend H8 was filled in a stainless steel tray (400 × 240 × 66 mmt) and temperature-controlled and humidity-controlled at a temperature of 50 ° C. and a relative humidity of 60%. Set. At this time, carbon dioxide gas was introduced into the system at 30 ml / min. After holding for 3.5 hours, the stainless steel tray was taken out from the constant temperature and humidity chamber to obtain an adherent holding material K8 having a weight increase rate of 1.5% by weight. The adherend holding material K8 was baked at 725 ° C. for 1.25 hours in an oxygen stream to obtain powder S8. It was 0.9 m < ² > / g when the BET specific surface area of powder S8 was measured.

(4) Charge / Discharge Performance Evaluation and Safety Evaluation Using the powder S8 as the positive electrode active material, the charge / discharge characteristics were measured under the same conditions as in Example 1. The initial discharge capacity was 182 mAh / g (after 20 cycles). The discharge capacity) / (discharge capacity after 10 cycles) ratio (cycle property) was 95.7%, indicating high capacity and high cycle property.
Further, DSC calorific value was measured under the same conditions as in Example 1 using Powder S8 as the positive electrode active material, and it was 440 mJ / mg.

(5) Measurement of element A elution rate (element A is Al.)
The powder S8 with an aqueous solution obtained by dissolving in hydrochloric acid, using ICP-AES (manufactured by Seiko Instruments Inc.) to determine the W _2. W ₂ was 0.015.
0.1 g of powder S8 and 10 ml of 1 mol / liter lithium hydroxide aqueous solution were put in a polypropylene container having a capacity of 15 ml. The container was immersed in a water bath at 60 ° C. for 4 hours, and the obtained supernatant was used. W ₁ was determined using ICP-AES. W ₁ was 0.00011. Therefore, the Al elution rate was calculated to be 0.7% by the formula W ₁ / W ₂ × 100.

In this example, the following conditions were used as conditions for using the ICP-AES apparatus unless otherwise specified.
Plasma power: 1.2kW
Carrier gas flow rate: 0.4 L / min
Plasma gas flow rate: 15 L / min
Auxiliary gas flow rate: 0.3 L / min
Al measurement wavelength: 396.15 nm

Example 7
(1) Manufacture of core material particles Lithium hydroxide (LiOH.H ₂ O; manufactured by Honjo Chemical Co., Ltd., pulverized product, average particle size of 10 to 25 μm) and nickel hydroxide (Ni (OH) ₂ ; Kansai Catalyst Chemical Co., Ltd. Made by company, product name is nickel hydroxide No. 3) and cobalt oxide (Co ₃ O ₄ ; manufactured by Shodo Chemical Industry Co., Ltd., product name is cobalt oxide (HCO)) The raw material mixed powder was obtained by weighing so that it might become ratio, and mixing using a Laedige mixer (the Matsubo Co., Ltd. make, M-20 type | mold).
Li: Ni: Co = 1.05: 0.85: 0.15

The obtained raw material mixed powder was dried at 120 ° C. for 10 hours, and then pulverized and mixed under the following conditions using a dynamic mill (MYD-5XA type, manufactured by Mitsui Mining Co., Ltd.).
Grinding media: 5mmφ high alumina (6.1kg)
Number of rotations of agitator shaft: 650 rpm
Supply amount of dry raw material mixed powder: 12.0kg / h
The pulverized raw material powder was filled into an alumina sheath and fired at 730 ° C. for 15 hours in an oxygen stream to obtain a lump. This lump was pulverized with a dry ball mill using a 15 mmφ nylon-coated steel ball as a pulverization medium, and the volume-based average particle size was 5.5 μm (laser diffraction particle size distribution analyzer SALD-1100 (Shimadzu Corporation). The core material particles C9 were obtained by pulverization until the measurement was obtained. The obtained core material particle C9 was confirmed to have an α-NaFeO ₂ type structure by powder X-ray diffraction.

(2) Production method of adherend material 900 g of the obtained core material particles C9 and 37.6 g of aluminum oxide (manufactured by Nippon Aerosil Co., Ltd., primary particle diameter 13 nm, product name is alumina C) (core material particles C8 (Added so as to be 0.08 mol part of Al element with respect to (Ni + Co) in the inside) in a polyethylene pot with an internal volume of 5 L, and using 4.2 kg of 15 mmφ nylon-coated steel balls as a medium at 80 rpm A dry ball mill was mixed for 30 minutes to obtain an adherend H9.

(3) Treatment of adherend A constant temperature and humidity chamber in which 180 g of the obtained adherend H9 was filled in a stainless steel tray (400 × 240 × 66 mmt) and temperature-controlled and humidity-controlled at a temperature of 50 ° C. and a relative humidity of 60%. Set. At this time, carbon dioxide gas was introduced into the system at 8 ml / min. After holding for 2.0 hours, the stainless steel tray was taken out of the constant temperature and humidity chamber to obtain an adherent holding material K9 having a weight increase rate of 1.0% by weight. The adherend holding material K9 was fired at 725 ° C. for 1.0 hour in an oxygen stream to obtain powder S9. It was 1.0 m < ² > / g when the BET specific surface area of powder S9 was measured.

(4) Charge / Discharge Performance Evaluation and Safety Evaluation Using the powder S9 as the positive electrode active material, the charge / discharge characteristics were measured under the same conditions as in Example 1. The initial discharge capacity was 185 mAh / g (after 20 cycles). The (discharge capacity) / (discharge capacity after 10 cycles) ratio (cycle property) was 96.0%, indicating a high capacity and a high cycle property.
Moreover, when DSC heat generation amount was measured on the same conditions as Example 1 using powder S9 for a positive electrode active material, it was 470 mJ / mg.

(5) Measurement of element A elution rate (element A is Al.)
The powder S9 with an aqueous solution obtained by dissolving in hydrochloric acid, using ICP-AES (manufactured by Seiko Instruments Inc.) to determine the W _2. W ₂ was 0.016.
0.1 g of powder S9 and 10 ml of 1 mol / liter lithium hydroxide aqueous solution were put in a polypropylene container having a capacity of 15 ml. The container was immersed in a water bath at 60 ° C. for 4 hours, and the obtained supernatant was used. W ₁ was determined using ICP-AES. W ₁ was 0.000069. Therefore, the Al elution rate was calculated to be 0.4% by the formula W ₁ / W ₂ × 100.

Example 8
180 g of the adherend H9 obtained in Example 7 was filled in a stainless steel tray (400 × 240 × 66 mmt), and set in a constant temperature and humidity chamber adjusted to a temperature of 50 ° C. and a relative humidity of 60%. At this time, carbon dioxide gas was introduced into the system at 8 ml / min. After holding for 4.8 hours, the stainless steel tray was taken out of the constant temperature and humidity chamber to obtain an adherent holding material K10 having a weight increase rate of 2.0% by weight. The adherend holding material K10 was fired in an oxygen stream at 725 ° C. for 1.0 hour to obtain a powder S10. It was 1.0 m < ² > / g when the BET specific surface area of powder S10 was measured. Using the obtained powder S10, the charge / discharge characteristics were measured under the same conditions as in Example 1. The initial discharge capacity was 186 mAh / g, (discharge capacity after 20 cycles) / (discharge capacity after 10 cycles). The ratio (cycle property) was 95.6%, indicating a high capacity and a high cycle property.
Moreover, when DSC heat generation amount was measured on the same conditions as Example 1 using powder S10 for a positive electrode active material, it was 480 mJ / mg.

The powder S10 with an aqueous solution obtained by dissolving in hydrochloric acid, using ICP-AES (manufactured by Seiko Instruments Inc.) to determine the W _2. W ₂ was 0.016.
0.1 g of powder S10 and 10 ml of 1 mol / liter lithium hydroxide aqueous solution were put in a polypropylene container having a capacity of 15 ml. The container was immersed in a water bath at 60 ° C. for 4 hours, and the obtained supernatant was used. W ₁ was determined using ICP-AES. W ₁ was 0.00020. Therefore, the Al elution rate was calculated to be 1.2% by the formula W ₁ / W ₂ × 100.

Comparative Example 6
The holding | maintenance process in the atmosphere containing water was abbreviate | omitted for the to-be-adhered material H9 obtained in Example 7, and powder S11 was obtained by baking at 725 degreeC for 1.0 hour in oxygen stream. It was 1.1 m < ² > / g when the BET specific surface area of powder S11 was measured. Using the obtained powder S11, the charge / discharge characteristics were measured under the same conditions as in Example 1. The initial discharge capacity was 186 mAh / g, (discharge capacity after 20 cycles) / (discharge capacity after 10 cycles). The ratio (cycleability) was 96.1%, indicating high capacity and high cycleability.
However, when the DSC calorific value was measured under the same conditions as in Example 1 using Powder S11 as the positive electrode active material, it was 590 mJ / mg, which was larger than Example 7.

The powder S11 with an aqueous solution obtained by dissolving in hydrochloric acid, using ICP-AES (manufactured by Seiko Instruments Inc.) to determine the W _2. W ₂ was 0.016.
0.1 g of powder S11 and 10 ml of 1 mol / liter lithium hydroxide aqueous solution were placed in a polypropylene container having a capacity of 15 ml. The container was immersed in a water bath at 60 ° C. for 4 hours, and the obtained supernatant was used. W ₁ was determined using ICP-AES. W ₁ was 0.00052. Therefore, the Al elution rate was calculated to be 3.2% by the formula W ₁ / W ₂ × 100.

Claims (19)

  Contains element A (one or more elements selected from B, Al, Ga, In, Si, Ge, Sn, Mg, and transition metal elements) on the particle surface of a material that can be doped / undoped with lithium ions After holding the adherend to which the compound to be deposited is placed in a water-containing atmosphere so that the weight increase rate of the adherend is in the range of 0.1 wt% or more and 5.0 wt% or less, A method for producing an active material for a non-aqueous secondary battery, comprising firing the product.   2. The production of an active material for a non-aqueous secondary battery according to claim 1, wherein the temperature maintained in the atmosphere containing water is in the range of 20 ° C. or more and 90 ° C. or less and the relative humidity is in the range of 20% or more and 90% or less. Method.   3. The non-aqueous solution according to claim 1, wherein the material capable of doping and dedoping lithium ions is a lithium nickel composite oxide, and the active material for non-aqueous secondary battery is a positive electrode active material for non-aqueous secondary battery. A method for producing an active material for a secondary battery. A material that can be doped / undoped with lithium ions has a general formula Li _x Ni _{1- y My} O ₂ (where x and y are 0.9 ≦ x ≦ 1.2 and 0 ≦ y ≦ 0.5, respectively). And M is one or more elements selected from B, Al, Ga, In, Si, Ge, Sn, Mg, and transition metal elements. The manufacturing method of the active material for nonaqueous secondary batteries in any one of.   The method for producing an active material for a non-aqueous secondary battery according to claim 4, wherein M is one or more elements selected from B, Al, Mg, Co, Cr, Mn, and Fe. The material capable of doping and dedoping lithium ions is represented by the general formula Li _x Ni ₁ -z M ² _z O ₂ (where x and z are 0.9 ≦ x ≦ 1.2 and 0.3 ≦ z ≦ 0, respectively). And M ² is a composition represented by 2 or more elements selected from B, Al, Si, Sn, Mg, Mn, Fe and Co. The manufacturing method of the active material for nonaqueous secondary batteries in any one of.   The element A is one or more elements selected from B, Al, Mg, Co, Cr, Mn, and Fe. The production of the active material for a non-aqueous secondary battery according to any one of claims 1 to 6. Method.   Element A is Al, The manufacturing method of the active material for nonaqueous secondary batteries in any one of Claims 1-6 characterized by the above-mentioned.   The method for producing an active material for a non-aqueous secondary battery according to any one of claims 1 to 8, wherein the compound containing the element A is an oxide, hydroxide, oxyhydroxide, carbonate or a mixture thereof. .   The non-water according to any one of claims 1 to 9, wherein the BET specific surface area of the compound containing the element A is at least 5 times the BET specific surface area of the material capable of doping and dedoping lithium ions. A method for producing an active material for a secondary battery.   The active for a non-aqueous secondary battery according to any one of claims 1 to 10, wherein the process of depositing the compound containing the element A on the particle surface of a material capable of doping and dedoping lithium ions is dry mixing. A method for producing a substance.   The method for producing an active material for a non-aqueous secondary battery according to claim 1, wherein carbon dioxide gas is supplied while the adherend is held in an atmosphere containing water.   The non-water according to any one of claims 1 to 12, wherein an atmosphere in which the adherend is held in a water-containing atmosphere until a predetermined weight increase rate is obtained and then the atmosphere in which the substrate is fired has an oxygen concentration of 90% by volume or more. A method for producing an active material for a secondary battery.   The holding material is held in an atmosphere containing water until a predetermined weight increase rate is reached, and then the firing temperature is 600 ° C or higher and the holding time is 30 minutes or longer. The manufacturing method of the active material for non-aqueous secondary batteries as described in 2 ..   A non-aqueous secondary battery active material produced by the production method according to claim 1. Contains element A (one or more elements selected from B, Al, Ga, In, Si, Ge, Sn, Mg, and transition metal elements) on the particle surface of a material that can be doped / undoped with lithium ions An active material for a non-aqueous secondary battery produced by firing an adherend on which a compound to be adhered is deposited, and when the active material and an alkaline solution are mixed, the active material is converted into the alkaline solution. The weight ratio (W ₁ ) of the extracted element A is 3.0% or less with respect to the weight ratio (W ₂ ) of the element A contained in the active material before mixing. Active material for water secondary battery. Contains element A (one or more elements selected from B, Al, Ga, In, Si, Ge, Sn, Mg, and transition metal elements) on the particle surface of a material that can be doped / undoped with lithium ions After holding the adherend to which the compound to be deposited is placed in a water-containing atmosphere so that the weight increase rate of the adherend is in the range of 0.1 wt% or more and 5.0 wt% or less, An active material for a non-aqueous secondary battery produced by firing this, and when the active material and an alkaline solution are mixed, the weight ratio (W) of the element A extracted from the active material into the alkaline solution _1), relative to the weight percentage of the element a contained in the active material before the mixing (W _2), for a non-aqueous secondary battery according to claim 16, wherein a is not more than 3.0% Active material.   A nonaqueous secondary battery comprising the nonaqueous secondary battery quality active material according to any one of claims 15 to 17. Contains element A (one or more elements selected from B, Al, Ga, In, Si, Ge, Sn, Mg, and transition metal elements) on the particle surface of a material that can be doped / undoped with lithium ions A method for evaluating an active material for a non-aqueous secondary battery produced by firing an adherend on which a compound to be deposited is deposited, wherein the weight ratio (W ₁ ) of the element A contained in the active material is determined. An active material for a non-aqueous secondary battery, characterized in that the active material and an alkaline solution are mixed and the weight ratio (W ₂ ) of the element A extracted from the active material into the alkaline solution is determined. Method.