JP2016154121A - Negative electrode active material for nonaqueous electrolyte secondary battery, negative electrode, and nonaqueous electrolyte secondary battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide: a negative electrode active material for a nonaqueous electrolyte secondary battery having a superior rate characteristic; a negative electrode including such a negative electrode active material; and a nonaqueous electrolyte secondary battery having such a negative electrode.SOLUTION: A negative electrode active material for a nonaqueous electrolyte secondary battery comprises: a material A; and a transition metal deposited on the material A. The material A includes at least one kind of material selected from the group consisting of a carbon material, a metal, a semimetal, an alloy, an oxide and a nitride, which are capable of occluding and releasing lithium ions electrochemically. The rate of the transition metal to the material A is 10 or more and 1000 or less mass ppm. A negative electrode comprises the negative electrode active material. A nonaqueous electrolyte secondary battery comprises the negative electrode.SELECTED DRAWING: None

Description

  The present invention relates to a negative electrode active material for a non-aqueous electrolyte secondary battery, a negative electrode including the same, and a non-aqueous electrolyte secondary battery having the same.

  With the recent development of electronic technology and increasing interest in environmental technology, various electrochemical devices have been developed. In particular, since there are many requests for energy saving, expectations for electrochemical devices that can contribute to energy saving are increasing. Examples of such electrochemical devices include power storage devices such as non-aqueous electrolyte secondary batteries.

  Lithium ion secondary batteries, which are also representative examples of nonaqueous electrolyte secondary batteries, have been used mainly as rechargeable batteries for portable devices, but in recent years, they are also expected to be used as batteries for hybrid and electric vehicles. . When a lithium ion secondary battery is used in an automobile, it is required to be used with a larger current than in the case where it is used for a portable device as in the past.

  Patent Document 1 discloses that at least a part of the surface of a carbon material is coated with an amorphous metal compound containing a metal that can be alloyed with lithium from the viewpoint of enhancing the characteristics of a current nonaqueous electrolyte secondary battery. A technique for improving the charge / discharge capacity with the negative electrode material made is disclosed.

Japanese Patent Laid-Open No. 2001-102047

  However, Patent Document 1 does not describe the rate characteristics of the nonaqueous electrolyte secondary battery. Here, the rate characteristic is a characteristic that the battery can be used even when the battery is discharged with a large current. For example, in order to achieve the effect of quickly accelerating when starting in an automobile application, it is important to improve rate characteristics. In view of this problem, the conventional non-aqueous electrolyte secondary battery still has room for improvement.

  Then, an object of this invention is to provide the negative electrode active material for nonaqueous electrolyte secondary batteries provided with the outstanding rate characteristic, the negative electrode containing the same, and a nonaqueous electrolyte secondary battery having the same.

  As a result of intensive studies to solve the above problems, the present inventors include, as a negative electrode active material used in a nonaqueous electrolyte secondary battery, a substance A and a transition metal attached to the substance A, and the substance A includes at least one selected from the group consisting of carbon materials, metals, metalloids, alloys, oxides, and nitrides capable of electrochemically occluding and releasing lithium ions, wherein The inventors have found that the above problem can be solved by using a transition metal ratio of 10 ppm by mass or more and 1000 ppm by mass or less, and completed the present invention.

That is, the present invention is as follows.
[1] A substance A and a transition metal attached to the substance A, and the substance A is a carbon material, metal, metalloid, alloy, oxide, and nitridation capable of electrochemically inserting and extracting lithium ions. A negative electrode active for a non-aqueous electrolyte secondary battery, comprising at least one selected from the group consisting of substances, wherein the ratio of the transition metal to the substance A is 10 mass ppm or more and 1000 mass ppm or less material.

[2] The non-aqueous electrolyte secondary according to [1], wherein the substance A is a carbon material, and the transition metal is at least one selected from the group consisting of Ni, Mn, Fe, and Co. Negative electrode active material for batteries.

[3] The negative electrode active material for a nonaqueous electrolyte secondary battery according to [1] or [2], wherein the ratio of the transition metal to the substance A is 10 mass ppm or more and 500 mass ppm or less.

[4] A negative electrode comprising the negative electrode active material for a nonaqueous electrolyte secondary battery according to any one of [1] to [3].

[5] A nonaqueous electrolyte secondary battery comprising the negative electrode according to [4].

  The nonaqueous electrolyte secondary battery having a negative electrode including the negative electrode active material for a nonaqueous electrolyte secondary battery of the present invention has excellent rate characteristics.

  Hereinafter, a mode for carrying out the present invention (hereinafter also referred to as “the present embodiment”) will be described in detail. The following embodiments are examples for explaining the present invention, and are not intended to limit the present invention to the following contents. The present invention can be implemented with appropriate modifications within the scope of the gist.

(Negative electrode active material)
The negative electrode active material according to this embodiment is used for a non-aqueous electrolyte secondary battery.
The negative electrode active material includes a substance A to be described later and a transition metal attached to the substance A. The substance A is a carbon material, metal, metalloid, alloy capable of electrochemically inserting and extracting lithium ions. And at least one selected from the group consisting of oxides and nitrides. Here, the ratio of the transition metal with respect to the substance A is 10 mass ppm or more and 1000 mass ppm or less.

-Substance A-
The carbon material capable of electrochemically occluding and releasing lithium ions that can be contained in the substance A may be a conventionally known carbon material such as hard carbon, soft carbon, artificial graphite, natural graphite, graphite, pyrolytic carbon, Examples include coke, glassy carbon, a fired body of an organic polymer compound, mesocarbon microbeads, carbon fiber, activated carbon, graphite, carbon colloid, and carbon black.
In particular, the coke may be a conventionally known one, and examples thereof include pitch coke, needle coke, and petroleum coke. In addition, the fired body of the organic polymer compound is obtained by firing and polymerizing a polymer material such as a phenol resin or a furan resin at an appropriate temperature.
These may be used alone or in combination of two or more.

The metal or semimetal that can be contained in the substance A may be a conventionally known metal. As a metal, metals other than a transition metal are preferable.
Examples of metal elements and metalloid elements include magnesium (Mg), calcium (Ca), aluminum (Al), titanium (Ti), zinc (Zn), silver (Ag), hafnium (Hf), and zirconium (Zr). Yttrium (Y), Tin (Sn), Lead (Pb), Indium (In), Silicon (Si), Antimony (Sb), Bismuth (Bi), Gallium (Ga), Germanium (Ge), Arsenic (As) Etc. Among these, the metal elements and metalloid elements of Group 4 or 14 in the long-period periodic table are preferable, and titanium (Ti), tin (Sn), and silicon (Si) are particularly preferable.
These may be used alone or in combination of two or more.

The alloy that can be included in the substance A includes an alloy including one or more metal elements and one or more metalloid elements in addition to an alloy including two or more metal elements (described above). Further, the alloy may have a nonmetallic element as long as it has metal properties as a whole.
In the structure of the alloy, a solid solution, a eutectic (eutectic mixture), an intermetallic compound, or two or more of these coexist.

The oxide that can be contained in the substance A may be a conventionally known oxide. For example, cobalt oxide, nickel oxide, iron oxide, silicon oxide, niobium pentoxide, tungsten oxide, molybdenum oxide, titanium dioxide, lithium titanate (for example, , Li ₄ Ti ₅ O ₁₂ etc.).
These may be used alone or in combination of two or more.

The nitride that can be contained in the substance A may be a conventionally known nitride, and examples thereof include those represented by the general formula: Li _3-x M _x N (M = Co, Ni, Mn).
These may be used alone or in combination of two or more.

  These carbon materials, metalloids, metals, alloys, oxides, and nitrides may be used alone or in combination of two or more.

  The substance A is preferably a carbon material that can electrochemically occlude and release lithium ions.

-Transition metal-
The transition metal attached to the substance A is an element existing between groups 3 to 11 in the long-period periodic table, and scandium (Sc), titanium (Ti), vanadium (V), chromium ( Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), and copper (Cu) are preferred, and manganese (Mn), iron (Fe), cobalt (Co), and nickel (Ni) Is more preferable.
These may be used alone or in combination of two or more.

The ratio of the transition metal to the substance A (the amount of the transition metal attached to the substance A) is 10 mass ppm or more, preferably 20 mass ppm or more, preferably 50 mass ppm with respect to the mass of the substance A. More preferably, it is 1000 ppm by mass or less, preferably 500 ppm by mass or less, and more preferably 450 ppm by mass or less.
When the ratio of the transition metal to the substance A is within the above range, a tendency to exhibit more excellent rate characteristics can be obtained.

  The ratio of the transition metal to the substance A can be measured by a conventionally known method, and can be measured and calculated by, for example, high frequency inductively coupled plasma emission spectroscopy (ICP-AES analysis).

  As a method of attaching the transition metal to the substance A, a conventionally known method may be used, and examples thereof include a chemical vapor deposition method and a physical vapor deposition method. The transition metal may be attached to at least a part of the substance A at the time of manufacturing the negative electrode active material, and the transition metal may be attached to at least a part of the substance A in the battery at the time of charge / discharge. You may go.

((Negative electrode))
The negative electrode according to the present embodiment includes the negative electrode active material for a nonaqueous electrolyte secondary battery according to the present embodiment described above.
And it is preferable that the negative electrode which concerns on this embodiment contains a electrically conductive material, a collector, and a binder (binder) other than the said negative electrode active material for nonaqueous electrolyte secondary batteries.

(Conductive material)
The conductive material that can be included in the negative electrode is not particularly limited, and may be a known material that can conduct electrons. As the conductive material, for example, non-graphitic carbonaceous materials such as graphite and carbon black (including acetylene black) and various cokes are preferable. These may be used alone or in combination of two or more.

(Current collector)
The current collector that can be included in the negative electrode is not particularly limited, and examples thereof include metal foils such as copper, nickel, and stainless steel, expanded metal, punch metal, foam metal, carbon cloth, and carbon paper.
These may be used alone or in combination of two or more.

(Binder (binder))
Known binders (binders) that can be included in the negative electrode can bind at least two selected from the group consisting of the negative electrode active material for non-aqueous electrolyte secondary batteries, the conductive material, and the current collector. Good.
Such a binder (binder) is not particularly limited, and for example, carboxymethyl cellulose, styrene-butadiene crosslinked rubber latex, acrylic latex, and polyvinylidene fluoride are preferable. These may be used alone or in combination of two or more.
The solvent that dissolves the binder (binder) is not particularly limited and may be any known solvent as long as it is a solvent that dissolves the binder (binder). Among these, water and N-methyl-2-pyrrolidone are preferable as the solvent. These may be used alone or in combination of two or more.

(((Nonaqueous electrolyte secondary battery)))
The nonaqueous electrolyte secondary battery according to the present embodiment includes the negative electrode according to the present embodiment described above.
And the nonaqueous electrolyte secondary battery which concerns on this embodiment may have a positive electrode, a nonaqueous electrolyte, a separator, an exterior body, etc. other than the said negative electrode. Such a nonaqueous electrolyte secondary battery has excellent rate characteristics.

((Positive electrode))
The positive electrode used in the non-aqueous electrolyte secondary battery according to the present embodiment preferably includes a positive electrode active material, a conductive material, a current collector, and a binder (binder).

(Positive electrode active material)
The positive electrode active material that can be included in the positive electrode is not particularly limited as long as it can electrochemically occlude and release lithium ions, and may be a known material.
In particular, the positive electrode active material is preferably a material containing lithium.
Such a positive electrode active material is not particularly limited.
Following formula (1):
_{Li x Ni 1-y M y} O z ··· (1)
(In the formula, M represents at least one element selected from the group consisting of transition metal elements, and 0 <x ≦ 1.3, 0 ≦ y <1, 1.8 <z <2.2. .)
An oxide represented by
Following formula (2):
_{Li x M y O z ··· (} 2)
(In the formula, M represents at least one element selected from the group consisting of transition metal elements, and 0 <x ≦ 1.3, 0.8 <y <1.2, 1.8 <z <2 .2)
A layered oxide represented by
Following formula (3):
_{Li x Mn 2-y M y} O z ··· (3)
(In the formula, M represents at least one element selected from the group consisting of transition metal elements, and 0 <x ≦ 1.3, 0.2 <y <0.8, 3.5 <z <4. .5.)
An oxide represented by
Following formula (4):
_{LiMn 2-x Ma x O 4} ··· (4)
(In the formula, Ma represents at least one element selected from the group consisting of transition metal elements, and 0.2 ≦ x ≦ 0.7.)
A spinel oxide represented by
Following formula (5-1):
Li ₂ McO ₃ (5-1)
(In the formula, Mc represents at least one element selected from the group consisting of transition metal elements.)
An oxide represented by
Following formula (5-2):
LiMdO ₂ (5-2)
(In the formula, Md represents at least one element selected from the group consisting of transition metal elements.)
A composite oxide with an oxide represented by the following formula (5-3):
_{zLi 2 McO 3 - (1-} z) LiMdO 2 ··· (5-3)
(In formula (5-3), Mc and Md have the same meanings as in formulas (5-1) and (5-2), respectively, and 0.1 ≦ z ≦ 0.9.)
Li-excess layered oxide positive electrode active material represented by
Following formula (6):
LiMb _1-y Fe _y PO ₄ (6)
(In the formula, Mb represents at least one element selected from the group consisting of Mn and Co, and 0 ≦ y ≦ 1.0.)
An olivine-type positive electrode active material represented by
Following formula (7):
Li ₂ MePO ₄ F (7)
(In the formula, Me represents at least one element selected from the group consisting of transition metal elements.)
The compound represented by these is mentioned.

  These may be used alone or in combination of two or more.

(Conductive material)
The conductive material that can be included in the positive electrode is not particularly limited, and may be a known material that can conduct electrons. As the conductive material, for example, activated carbon, various cokes, non-graphitic carbonaceous materials such as carbon black and acetylene black, graphite (graphite), and metal powders such as aluminum, titanium, and stainless steel are preferable. These may be used alone or in combination of two or more.

(Current collector)
The current collector that can be included in the positive electrode is not particularly limited, and examples thereof include metal foils such as aluminum, titanium, and stainless steel, expanded metal, punch metal, foam metal, carbon cloth, and carbon paper. These may be used alone or in combination of two or more.

(Binder (binder))
The binder (binder) that can be included in the positive electrode may be a known material that can bind at least two selected from the group consisting of the positive electrode active material, the conductive material, and the current collector.
As such a binder (binder), for example, polyvinylidene fluoride and fluororubber are preferable. These may be used alone or in combination of two or more.
The solvent that dissolves the binder (binder) is not particularly limited and may be any known solvent as long as it is a solvent that dissolves the binder (binder). Among these, N-methyl-2-pyrrolidone, ethyl acetate, and ethyl cellosolve are preferable as the solvent. These may be used alone or in combination of two or more.

((Nonaqueous electrolyte))
The nonaqueous electrolyte in the present embodiment may be a liquid electrolyte or a solid electrolyte. Examples of the liquid electrolyte include a non-aqueous electrolyte solution obtained by dissolving an electrolyte (salt) in a non-aqueous solvent. Examples of the solid electrolyte include those obtained by dispersing an electrolyte (salt) in a polymer, and polymers. The thing impregnated with the said non-aqueous electrolyte is mentioned.

(Electrolyte (salt))
The electrolyte (salt) used in the nonaqueous electrolyte secondary battery according to this embodiment is not particularly limited and may be a conventionally known one.
The electrolyte is preferably a lithium salt. For example, LiPF ₆ (lithium hexafluorophosphate), LiClO ₄ , LiAsF ₆ , Li ₂ SiF ₆ , LiOSO ₂ C _k F _{2k + 1} [k is an integer of 1 to 8] LiN (SO ₂ C _k F _{2k + 1} ) ₂ [k is an integer of 1 to 8], LiPF _n (C _k F _{2k + 1} ) _6-n [n is an integer of 1 to 5, k is 1 to 8 Integer], LiCF ₃ SO ₃ , LiC ₄ F ₉ SO ₃ , Li (CF ₃ SO ₂ ) ₃ C, LiAlO ₄ , LiAlCl ₄ , LiBF ₄ , LiBF _q (C _s F _{2s + 1} ) _4-q [q Is an integer of 1 to 3, s is an integer of 1 to 8], LiB (C ₆ F ₅ ) ₄ , LiB (C ₂ O ₄ ) ₂ , Li ₂ B ₁₂ F _b H _12-b [b is 0 to 3 _{integer], LiB (C 6 H 5)} 4, LiPF n (C k F 2k + 1) 6-n [n is an integer of 1 to 5, k is an integer of 1 to 8], LiPF ₄ (C ₂ O ₄ ), Li _{BF 2 (C 2 O 4)} , LiB (C 3 O 4 H 2) 2, LiPF 4 (C 2 O 2), LiPF 2 (C 2 O 4) 2 and the like. Among these, LiPF ₆ is preferable from the viewpoint of obtaining excellent rate characteristics and excellent cycle characteristics.
These may be used alone or in combination of two or more.

  The electrolyte in the present embodiment may be a liquid electrolyte or a solid electrolyte.

(Non-aqueous solvent)
The nonaqueous solvent used in the nonaqueous electrolyte secondary battery according to this embodiment is not particularly limited and may be a conventionally known one.
The non-aqueous solvent is preferably an aprotic polar solvent, for example, ethylene carbonate, propylene carbonate, 1,2-butylene carbonate, 2,3-butylene carbonate, 1,2-pentylene carbonate, 2,3-pentylene. Cyclic carbonates such as carbonate, trifluoromethylethylene carbonate, fluoroethylene carbonate and 4,5-difluoroethylene carbonate; lactones such as γ-butyrolactone and γ-valerolactone; cyclic sulfones such as sulfolane; cyclic ethers such as tetrahydrofuran and dioxane Ethyl methyl carbonate, dimethyl carbonate, diethyl carbonate, methyl propyl carbonate, methyl isopropyl carbonate, dipropyl carbonate, methyl butyl carbonate Chain carbonates such as carbonate, dibutyl carbonate, ethylpropyl carbonate and methyl trifluoroethyl carbonate; nitriles such as acetonitrile; chain ethers such as dimethyl ether; chain carboxylic acid esters such as methyl propionate; chain chains such as dimethoxyethane An ether carbonate compound etc. are mentioned.
These may be used alone or in combination of two or more.

((Separator))
The separator used in the non-aqueous electrolyte secondary battery according to the present embodiment is not particularly limited, and may be a conventionally known separator that has high ion permeability and electrically isolates the positive electrode and the negative electrode. Any function may be used.
Examples of the separator include a synthetic resin microporous film, a nonwoven fabric, papermaking, a porous film, a structure thereof, and a solid electrolyte film.
As a synthetic resin microporous film, what consists of polyolefin resin, such as polyethylene and a polypropylene, for example is preferable.
As a nonwoven fabric, papermaking, and a porous film, you may each consist of cellulose, aromatic polyamide, a fluororesin, polyolefin etc., for example.
These non-woven fabrics, papermaking, and porous membranes are composed of a mixture of the aforementioned resin and at least one inorganic material such as alumina or silica, or at least a part of the surface of the aforementioned resin. It may be coated with the inorganic material.

((Exterior body))
The exterior body used for the nonaqueous electrolyte secondary battery according to the present embodiment is not particularly limited and may be a conventionally known one. The material of the exterior body is not particularly limited, and examples thereof include metals such as stainless steel, iron, and aluminum, and laminate films in which the surface of the metal is coated with a resin.

  The nonaqueous electrolyte secondary battery according to the present embodiment may have the same configuration as that conventionally known except for the configuration described above. Examples of the nonaqueous electrolyte secondary battery according to this embodiment include a lithium ion secondary battery and a lithium ion capacitor.

  EXAMPLES Hereinafter, although an Example is given and embodiment of this invention is described, this invention is not limited to these Examples.

  The measurement methods and evaluation methods (1) and (2) of various physical properties in Examples and Comparative Examples are shown below.

(1) Measurement / calculation of ratio of transition metal to substance A (amount of transition metal attached to substance A) The amount of transition metal attached to the negative electrode active material obtained in the following examples and comparative examples, It calculated | required using the ICP emission-spectral-analysis apparatus (Perkin Elmer company make, product name: Optima8300), this was remove | divided by the mass of the substance A of the said negative electrode active material, and the ratio of the transition metal with respect to the substance A was computed. The results are shown in Table 1.

(2) 3C rate characteristic evaluation The cylindrical secondary batteries obtained in the following examples and comparative examples were charged and discharged in a constant temperature bath at a constant temperature of 20 ° C (product name, manufactured by Asuka Electronics Co., Ltd.). : ACD-01) was charged at a constant current of 0.3 C and a constant potential of 4.2 V (positive electrode-negative electrode potential) for 8 hours, and then discharged to a potential of 3.0 V at a constant current of 0.3 C. (Charging / discharging at the first cycle). Note that “1.0 C” refers to a current value at which a fully charged battery can discharge electricity in one hour.
After the first charge / discharge, after charging for 5 hours in a constant temperature and constant voltage system of 0.5C and 4.2V in a constant temperature: 20 ° C constant temperature chamber, the potential is set to 3.0V at a constant current of 3.0C. Discharged until At this time, the value represented by the following equation was used as the 3C rate characteristic. The results are shown in Table 1.
3C rate characteristic (%) = [(3C discharge amount) / (0.3C discharge amount)] × 100

  Hereinafter, each example and each comparative example will be described in detail.

[Example 1]
(A) Manufacture of negative electrode Natural graphite having an average particle diameter of 10 μm was heated in the atmosphere at a temperature of 150 ° C. for 1 hour while immersed in an aqueous solution of manganese (II) sulfate pentahydrate: 1 mol / L, and then Furthermore, it was heated for 3 hours at a temperature of 400 ° C. in a nitrogen atmosphere to obtain a powder. This powder was used as a negative electrode active material. The amount of Mn adhered to the obtained powder was 850 mass ppm.

For a total of 100 parts by mass of 90 parts by mass of the negative electrode active material obtained as described above and 10 parts by mass of artificial graphite having an average particle size of 5 μm, 1.4 parts by mass of carboxymethyl cellulose and styrene / butadiene latex Each 1.8 parts by mass as a solid content was mixed, and water was added as a dispersion medium to prepare a dispersion. At this time, the solid content concentration of the dispersion was 50% by mass.
The dispersion was applied on a copper foil having a thickness of 12 μm with a uniform thickness, and the step of drying the same was performed on both sides of the copper foil. Thereafter, this copper foil was roll-pressed to produce a negative electrode.

(B) Production of positive electrode Lithium cobaltate (LiCoO ₂ ) having an average particle diameter of 10 μm was used as the positive electrode active material.

2 parts by mass of graphite powder having an average particle size of 3.3 μm and 4 parts by mass of non-graphitic carbon powder having an average particle size of 0.04 μm were mixed with 100 parts by mass of the positive electrode active material to obtain a compound.
An N-methyl-2-pyrrolidone (hereinafter, also referred to as “NMP”) solution containing 6 parts by mass of polyvinylidene fluoride was added to this compound, and the compound was dispersed in this solution to prepare a dispersion. At this time, the solid content concentration of the dispersion was 60% by mass.
The dispersion was applied to a uniform thickness on an aluminum foil having a thickness of 15 μm, and the step of drying the same was performed on both sides of the aluminum foil. Then, the aluminum foil was roll-pressed to produce a positive electrode.

(C) Manufacture of nonaqueous electrolyte secondary battery The positive electrode and the negative electrode produced as described above were cut into a size of width: about 55 mm and length: 80 cm, and these were separated into a polyethylene microporous membrane having a thickness of 18 μm. (Porosity 50%, hole diameter: 0.1 μm to 1 μm) was wound in a roll shape with a diameter of about 17 mm. The wound coil was placed in an iron cylindrical can having a diameter of about 18 mm and a length of 65 mm. About 5 g of a mixture of ethylene carbonate and ethyl methyl carbonate (ethylene carbonate: ethyl methyl carbonate = 1: 3 (volume ratio)) in which LiPF ₆ was dissolved at a concentration of 1 mol / L was added to the can, and the can was sealed. A cylindrical nonaqueous electrolyte secondary battery was produced.
1.0 C of the battery using the negative electrode active material of Example 1 corresponded to 2000 mA. In addition, the 3C rate characteristic of the battery using the negative electrode active material of Example 1 was 80%.

[Example 2]
Manganese (II) sulfate pentahydrate: Example 2 in the same manner as in Example 1 except that an iron nitrate nonahydrate: 1 mol / L aqueous solution was used instead of the 1 mol / L aqueous solution. A negative electrode active material and a battery were obtained. Table 1 shows the results of ICP analysis of the obtained negative electrode active material. Table 1 shows the results of 3C rate characteristics evaluation of the battery using the negative electrode active material of Example 2.

[Example 3]
Manganese (II) sulfate pentahydrate: In the same manner as in Example 1, except that an aqueous solution of nickel (II) sulfate hexahydrate: 1 mol / L was used instead of an aqueous solution of 1 mol / L, A negative electrode active material and a battery of Example 3 were obtained. Table 1 shows the results of ICP analysis of the obtained negative electrode active material. Table 1 shows the results of 3C rate characteristics evaluation of the battery using the negative electrode active material of Example 3.

[Example 4]
Manganese (II) sulfate pentahydrate: Instead of the 1 mol / L aqueous solution, cobalt sulfate (II) sulfate heptahydrate: 1 mol / L aqueous solution was used in the same manner as in Example 1, The negative electrode active material and battery of Example 4 were obtained. Table 1 shows the results of ICP analysis of the obtained negative electrode active material. Table 1 shows the results of 3C rate characteristics evaluation of the battery using the negative electrode active material of Example 4.

[Example 5]
Manganese (II) sulfate pentahydrate: In the same manner as in Example 1, except that an aqueous solution of titanium (IV) sulfate: 1 mol / L was used instead of the aqueous solution of 1 mol / L, A negative electrode active material and a battery were obtained. Table 1 shows the results of ICP analysis of the obtained negative electrode active material. Table 1 shows the results of 3C rate characteristics evaluation of the battery using the negative electrode active material of Example 5.

[Example 6]
Manganese (II) sulfate pentahydrate: Example 6 in the same manner as in Example 1 except that a chromium nitrate nonahydrate: 1 mol / L aqueous solution was used instead of the 1 mol / L aqueous solution. A negative electrode active material and a battery were obtained. Table 1 shows the results of ICP analysis of the obtained negative electrode active material. Table 1 shows the results of 3C rate characteristics evaluation of the battery using the negative electrode active material of Example 6.

[Example 7]
Manganese (II) sulfate pentahydrate: The same procedure as in Example 1 except that an aqueous solution of manganese (II) sulfate pentahydrate: 0.05 mol / L was used instead of the aqueous solution of 1 mol / L. Thus, a negative electrode active material and a battery of Example 7 were obtained. Table 1 shows the results of ICP analysis of the obtained negative electrode active material. Table 1 shows the results of 3C rate characteristics evaluation of the battery using the negative electrode active material of Example 7.

[Example 8]
Manganese (II) sulfate pentahydrate: The same procedure as in Example 1 except that an aqueous solution of manganese (II) sulfate pentahydrate: 0.1 mol / L was used instead of the aqueous solution of 1 mol / L. Thus, a negative electrode active material and a battery of Example 8 were obtained. Table 1 shows the results of ICP analysis of the obtained negative electrode active material. Table 1 shows the results of 3C rate characteristics evaluation of the battery using the negative electrode active material of Example 8.

[Example 9]
Manganese (II) sulfate pentahydrate: The same operation as in Example 1 except that an aqueous solution of manganese (II) sulfate pentahydrate: 0.5 mol / L was used instead of the aqueous solution of 1 mol / L. Thus, a negative electrode active material and a battery of Example 9 were obtained. Table 1 shows the results of ICP analysis of the obtained negative electrode active material. Table 1 shows the results of 3C rate characteristics evaluation of the battery using the negative electrode active material of Example 9.

[Example 10]
Nickel (II) sulfate hexahydrate: The same procedure as in Example 3 except that an aqueous solution of nickel (II) sulfate hexahydrate: 1.2 mol / L was used instead of the aqueous solution of 1 mol / L. Thus, a negative electrode active material and a battery of Example 10 were obtained. Here, in particular, in Example 10, the battery was charged and discharged for one cycle. Table 1 shows the results of ICP analysis of the negative electrode active material after charging and discharging. In addition, Table 1 shows the results of 3C rate characteristics evaluation of the battery using the negative electrode active material of Example 10 (uncharged / discharged battery).

[Example 11]
A negative electrode active material of Example 11 was obtained in the same manner as in Example 9, except that silicon (Si) having an average particle diameter of 5 μm was used instead of natural graphite having an average particle diameter of 10 μm. Table 1 shows the results of ICP analysis of the obtained negative electrode active material.
8 parts by mass of polyvinylidene fluoride is mixed with 100 parts by mass of 90 parts by mass of the negative electrode active material obtained as described above and 10 parts by mass of artificial graphite having an average particle size of 5 μm, and N-methyl- 2-Pyrrolidone (NMP) was added as a dispersion medium to prepare a dispersion. At this time, the solid content concentration of the dispersion was 50% by mass.
The dispersion was applied on a copper foil having a thickness of 12 μm to a uniform thickness, and the step of drying the same was performed on both sides of the copper foil. Thereafter, this copper foil was roll-pressed to produce a negative electrode.
A battery of Example 11 was obtained in the same manner as in Example 9, except for the above. The results of 3C rate characteristics evaluation of the obtained battery are shown in Table 1.

[Example 12]
A negative electrode active material of Example 12 was obtained in the same manner as in Example 9, except that Li ₄ Ti ₅ O ₁₂ having an average particle diameter of 5 μm was used instead of natural graphite having an average particle diameter of 10 μm. Table 1 shows the results of ICP analysis of the obtained negative electrode active material.
8 parts by mass of polyvinylidene fluoride is mixed with 100 parts by mass of 90 parts by mass of the negative electrode active material obtained as described above and 10 parts by mass of artificial graphite having an average particle size of 5 μm, and N-methyl A dispersion was prepared by adding -2-pyrrolidone as a dispersion medium. At this time, the solid content concentration of the dispersion was 50% by mass.
The dispersion was applied on a copper foil having a thickness of 12 μm to a uniform thickness, and the step of drying the same was performed on both sides of the copper foil. Thereafter, this copper foil was roll-pressed to produce a negative electrode.
A battery of Example 12 was obtained in the same manner as in Example 9, except for the above. The results of 3C rate characteristics evaluation of the obtained battery are shown in Table 1.

[Comparative Example 1]
Manganese (II) sulfate pentahydrate: In the same manner as in Example 1, except that an aqueous solution of manganese (II) sulfate pentahydrate: 2 mol / L was used instead of an aqueous solution of 1 mol / L, The negative electrode active material and battery of Comparative Example 1 were obtained. Table 1 shows the results of ICP analysis of the obtained negative electrode active material. Table 1 shows the results of 3C rate characteristics evaluation of the battery using the negative electrode active material of Comparative Example 1.

[Comparative Example 2]
Manganese (II) sulfate pentahydrate: The same operation as in Example 1 except that an aqueous solution of manganese (II) sulfate pentahydrate: 0.01 mol / L was used instead of the aqueous solution of 1 mol / L. Thus, a negative electrode active material and a battery of Comparative Example 2 were obtained. Table 1 shows the results of ICP analysis of the obtained negative electrode active material. Table 1 shows the results of 3C rate characteristics evaluation of the battery using the negative electrode active material of Comparative Example 2.

[Comparative Example 3]
The negative electrode active material and battery of Comparative Example 3 were the same as Example 1 except that natural graphite having an average particle size of 10 μm was not immersed in an aqueous solution of manganese (II) sulfate pentahydrate: 1 mol / L. Got. Table 1 shows the results of 3C rate characteristics evaluation of the battery using the negative electrode active material of Comparative Example 3.

[Comparative Example 4]
The negative electrode active material of Comparative Example 4 was prepared in the same manner as in Example 11 except that silicon (Si) having an average particle size of 5 μm was not immersed in an aqueous solution of manganese (II) sulfate pentahydrate: 1 mol / L. And a battery was obtained. Table 1 shows the results of 3C rate characteristics evaluation of the battery using the negative electrode active material of Comparative Example 4.

[Comparative Example 5]
The negative electrode of Comparative Example 5 was prepared in the same manner as in Example 12 except that Li ₄ Ti ₅ O ₁₂ having an average particle size of 5 μm was not immersed in an aqueous solution of manganese (II) sulfate pentahydrate: 1 mol / L. An active material and a battery were obtained. Table 1 shows the result of 3C rate characteristic evaluation of the battery using the negative electrode active material of Comparative Example 5.

  The negative electrode active material for nonaqueous electrolyte secondary batteries of the present invention has industrial applicability as a negative electrode active material for nonaqueous electrolyte secondary batteries such as lithium ion secondary batteries and lithium ion capacitors. The nonaqueous electrolyte secondary battery having a negative electrode including the negative electrode active material for a nonaqueous electrolyte secondary battery of the present invention has excellent rate characteristics.

Claims (5)

A substance A and a transition metal attached to the substance A,
The substance A includes at least one selected from the group consisting of carbon materials, metals, metalloids, alloys, oxides, and nitrides capable of electrochemically absorbing and releasing lithium ions,
The negative electrode active material for a nonaqueous electrolyte secondary battery, wherein the ratio of the transition metal to the substance A is 10 mass ppm or more and 1000 mass ppm or less. The substance A is a carbon material capable of electrochemically inserting and extracting lithium ions,
The transition metal is at least one selected from the group consisting of Ni, Mn, Fe and Co;
The negative electrode active material for nonaqueous electrolyte secondary batteries according to claim 1. The ratio of the transition metal to the substance A is 10 mass ppm or more and 500 mass ppm or less.
The negative electrode active material for nonaqueous electrolyte secondary batteries according to claim 1 or 2.   The negative electrode characterized by including the negative electrode active material for nonaqueous electrolyte secondary batteries of any one of Claims 1-3.   A nonaqueous electrolyte secondary battery comprising the negative electrode according to claim 4.