JP2002008654A - Positive electrode active material and its manufacturing method and non-aqueous electrolyte battery and its manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a positive electrode active material and a non-aqueous electrolyte secondary battery having outstanding high temperature characteristics, at low cost and in a stabilized manner. SOLUTION: The positive electrode active material 2 consists of a spinel type lithium manganese oxide expressed with general formula Li1+XAlYMn2-X-YO4 (in the formula, 0<=X<=0.15, and 0<Y<=0.3), and having a grating constant a Å in a range shown with formula below.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a positive electrode active material used in a chargeable / dischargeable secondary battery used as a power source for various electronic devices, a method for producing the same, and a non-aqueous electrolyte solution provided with the active material. The present invention relates to a secondary battery and a manufacturing method thereof.

[0002]

2. Description of the Related Art In recent years, along with the remarkable progress of various electronic devices, a rechargeable secondary battery has been studied as a power source that can be used conveniently and economically for a long time. As typical secondary batteries, lead storage batteries, alkaline storage batteries, lithium secondary batteries, and the like are known. Among these secondary batteries, lithium secondary batteries have advantages such as high output and high energy density.

[0003] A lithium secondary battery is composed of a positive electrode using an active material that reversibly electrochemically reacts with lithium ions, metallic lithium or a negative electrode containing lithium, and a non-aqueous electrolyte. In general, the discharge reaction of a lithium secondary battery proceeds when lithium ions are eluted into a non-aqueous electrolyte at a negative electrode and lithium ions intercalate between layers of an active material at a positive electrode.
Conversely, when charging a lithium secondary battery, the above-described discharge reaction and the reverse reaction proceed, and lithium ions are deintercalated at the positive electrode. Therefore, in the lithium secondary battery, charge and discharge are repeated based on a reaction in which the titanium ions supplied from the negative electrode enter and exit the positive electrode active material.

Generally, as a negative electrode active material of a lithium secondary battery, lithium metal, a lithium alloy such as a Li-Al alloy, a conductive polymer doped with lithium such as polyacetylene or polypyrrole, or lithium ions are incorporated in a crystal. Interlayer compounds and the like are used. On the other hand, a metal oxide, a metal sulfide, a polymer, or the like is used as the positive electrode active material. For example, TiS ₂ , MoS ₂ , NbSe ₂ , V ₂ O
_{5 and the} like, but in recent years, as a positive electrode active material having a high discharge potential and a high energy density, Li _X C
o _Y O ₂ is noted, a non-aqueous electrolyte secondary battery using the same have been put into practical use. Here, the value of X changes depending on charging and discharging, but X and Y are usually about 1 during synthesis.

[0005] Cobalt, which is a raw material of this composite oxide, is scarce in terms of resources, and is expensive and fluctuates greatly in price due to the uneven distribution of commercially available ore deposits in a few countries. Is accompanied by supply anxiety. For this reason, in order to promote the widespread use of lithium secondary batteries, as a positive electrode active material composed of raw materials that are cheaper and more resource-rich than cobalt and that are not inferior in performance compared to lithium-cobalt composite oxide, Use of LiNiO ₂ or LiMn ₂ O ₄ is being studied. In particular, manganese is inexpensive compared to nickel as well as cobalt, and is rich in resources. Manganese dioxide is distributed in large quantities as a material for manganese dry batteries, alkaline manganese dry batteries, and lithium primary batteries.
It is a material that is less anxious in terms of material supply. For this reason, research on a lithium manganese composite oxide as a positive electrode active material of a non-aqueous electrolyte secondary battery using manganese as a raw material has been actively conducted in recent years. Among them, the lithium manganese composite oxide having a spinel structure has a potential of 3 V or more with respect to lithium when electrochemically oxidized, and 148 mAh / g.
It has been reported that the material has the theoretical charge / discharge capacity.

[0006]

However, a lithium ion non-aqueous electrolyte secondary battery using a manganese oxide or a lithium manganese composite oxide as a positive electrode active material has a charge / discharge cycle with repetition of charge / discharge. There is a problem that characteristics are deteriorated. In particular, when used in a high temperature environment, that is, a temperature environment exceeding room temperature, the deterioration is remarkable.

[0007] Deterioration of battery performance at high temperatures is a problem to be especially noted in the case of a large non-aqueous electrolyte secondary battery for electric vehicles or road leveling. This is because, as the size of the battery increases, the internal heat generation during use cannot be ignored, and the possibility that the inside of the battery becomes relatively high even when the use environment temperature is around room temperature increases.
Also, considering that a small battery used for a small portable device or the like can be used in a high-temperature environment such as a car interior, deterioration of battery characteristics in a temperature environment equal to or higher than room temperature is as small as possible. desirable.

Accordingly, the present invention has been made in view of the above-mentioned conventional circumstances, and provides a positive electrode active material and a non-aqueous electrolyte secondary battery having excellent high-temperature characteristics at low cost and in a stable manner. The purpose is to:

[0009]

Means for Solving the Problems The positive electrode active material according to the present invention has a general formula Li _{1 + X} Al _Y Mn _2-XY O ₄ (where 0 ≦ X ≦
0.15, and 0 <Y ≦ 0.3. ),
It is characterized by being composed of a spinel-type lithium manganese oxide having a lattice constant aÅ in the range of the following expression.

[0010]

(Equation 5)

The cathode active material according to the present invention has the general formula Li
_{1 + X} Al _Y Mn _2-XY O ₄ (wherein 0 ≦ X ≦ 0.15 and 0 <Y ≦), comprising a spinel-type lithium manganese oxide. Here, in this positive electrode active material, an excess amount of lithium and Al replacing manganese were used.
Is defined as a predetermined amount. Thereby, the positive electrode active material according to the present invention can obtain good charge / discharge capacity. Further, in this positive electrode active material, the lattice constant aÅ is defined in a predetermined range. Accordingly, the positive electrode active material according to the present invention ensures that Mn is A in the spinel-type lithium manganese oxide represented by the general formula LiMn ₂ O _4.
Li _{1 + X} Al _Y Mn _2-XY O ₄ substituted with ₁ (where 0 ≦
X ≦ 0.15 and 0 <Y ≦ 0.3. ), The deterioration under a high temperature, that is, a temperature environment equal to or higher than room temperature is suppressed, and the charge / discharge cycle characteristics under a high temperature, that is, a temperature environment equal to or higher than room temperature are reliably improved.

The method for producing a positive electrode active material according to the present invention is based on the general formula Li _{1 + X} M _Y Mn _2-XY O ₄ (where 0 ≦ X ≦ 0.15
And 0 <Y ≦ 0.3. M represents a metal element. A method for producing a positive electrode active material comprising a spinel-type lithium manganese oxide represented by), wherein the Li raw material, the M raw material, and the Mn raw material as the raw materials of the positive electrode active material are ground and mixed using a planetary ball mill. It is characterized by the following.

In the method for producing a positive electrode active material according to the present invention, a Li raw material, an M raw material, and a Mn raw material as raw materials of the positive electrode active material are pulverized and mixed using a planetary ball mill. This ensures that Mn in LiMn ₂ O ₄ and the substituted metal M are substituted by the general formula Li _{1 + X MY} Mn2 _-XY O ₄ (where 0 ≦
X ≦ 0.15 and 0 <Y ≦ 0.3. ) Can be produced. Therefore, according to the method for producing a positive electrode active material according to the present invention, it is possible to produce a positive electrode active material that is less deteriorated at high temperatures, that is, in a temperature environment equal to or higher than room temperature and has excellent charge-discharge cycle characteristics.

A non-aqueous electrolyte secondary battery according to the present invention includes a negative electrode having lithium, a lithium alloy or a material capable of doping and undoping lithium, a positive electrode, and a non-aqueous electrolyte. Formula Li _{1 + X} Al _Y Mn _2-XY O ₄ (wherein
0 ≦ X ≦ 0.15 and 0 <Y ≦ 0.3. ) Wherein the positive electrode active material comprises a spinel-type lithium manganese oxide having a lattice constant aÅ represented by the following formula.

[0015]

(Equation 6)

The non-aqueous electrolyte secondary battery according to the present invention has a general formula Li _{1 + X} Al _Y Mn _2-XY O ₄ (where 0 ≦ X ≦ 0.15
And 0 <Y ≦ 0.3. ) And a positive electrode containing a positive electrode active material composed of a spinel-type lithium manganese oxide having a lattice constant aÅ represented by the above formula. Therefore, in this nonaqueous electrolyte battery, the deterioration of the positive electrode under a high temperature, that is, a temperature environment equal to or higher than room temperature is suppressed, and the charge / discharge cycle characteristics are excellent.

The method for producing a non-aqueous electrolyte secondary battery according to the present invention comprises the steps of:
A method for producing a non-aqueous electrolyte battery comprising a negative electrode having a undoped material, a positive electrode, and a non-aqueous electrolyte, wherein the positive electrode has a general formula Li _{1 + X} M _Y Mn _{2-X- Y} O ₄ (where 0 ≦ X ≦
0.15, and 0 <Y ≦ 0.3. M is
Represents a metal element. ) Containing a positive electrode active material composed of a spinel-type lithium manganese oxide, and pulverizing Li raw material, M raw material and Mn raw material as raw materials of the positive active material.
The mixing is performed using a planetary ball mill.

The method of manufacturing a non-aqueous electrolyte secondary battery according to the present invention is characterized in that when producing a spinel-type lithium manganese oxide as a positive electrode active material, a Li raw material, an M raw material and a Mn The raw materials are crushed and mixed using a planetary ball mill. This ensures that Mn in LiMn ₂ O ₄ and the substituted metal M are replaced by the general formula Li _{1 + X MY} M
n _{2 -XYO 4} (where 0 ≦ X ≦ 0.15 and 0 <Y ≦
0.3. ) Can be produced. Therefore, according to the method for producing a non-aqueous electrolyte battery according to the present invention, high temperature,
That is, a non-aqueous electrolyte battery that is less deteriorated in a temperature environment equal to or higher than room temperature and has excellent charge / discharge cycle characteristics can be manufactured.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the drawings. It should be noted that the present invention is not limited to the following description, and can be appropriately changed without departing from the gist of the present invention.

At present, as a positive electrode active material of a lithium battery,
Various materials have been studied, and one of them is a spinel-type lithium manganese oxide. Recently, for example, a spinel-type lithium manganese oxide represented by the general formula LiMn ₂ O ₄ is represented by a general formula Li _{1 + X} Al _Y Mn _{2-XYO 4 in} which Mn is replaced with another metal element. Spinel-type lithium manganese oxides have been proposed.
The spinel-type lithium manganese oxide represented by the general formula Li _{1 + X} Al _Y Mn _2-XY O ₄ is inexpensive, can be supplied stably, has excellent charge / discharge capacity, and has a high temperature. That is, attention has been paid from the viewpoint of having charge / discharge cycle characteristics under a temperature environment exceeding room temperature.

By the way, Li_{1 + X}Al_YMn_2-XYO_FourIs
A mixture of Li, Al and Mn materials as raw materials
It is manufactured by firing together.
Li_{1 + X}Al_YMn_2-XYO_FourConfirm and study the manufacturing method of
Then, Li_{1 + X}Al_YMn _2-XYO_FourIs simply Li material
Material, Al material and Mn material mixed and fired
n_TwoO_FourIn which Al is replaced by Mn_{1 + X}Al_YM
n_2-XYO_Four-Type lithium manganese oxidation expressed by
It has been found that the probability of forming an object is low. That is, the conventional
Simply mix Li material, Al material and Mn material and bake
Li method_{1 + X}Al_YMn_2-XYO_FourIf you make
Is a part of the Al
Li_{1 + X}Al_YMn_2-XYO_FourSpinel type lithium
Manganese oxides, but most of the Al
Fastened Al_TwoO_ThreeWill remain. Soshi
Therefore, when the product is identified by X-ray diffraction,
Is Li_{1 + X}Al_YMn_2-XYO_FourIs confirmed,
Since the Al peak is not confirmed,
All dissolved in Li_{1 + X}Al_YMn_2-XYO_FourForm
It is mistaken for something.

Further, all of the introduced Al raw materials form a solid solution and
i_{1 + X}Al_YMn_2-XYO_FourNot forming the fabrication
The lattice constant of doped lithium manganese oxide
Can be confirmed by That is, LiMn_TwoO_Fourof
Mn is replaced by Al and Li _{1 + X}Al_YMn_2-XYO_FourTona
Then, the lattice constant decreases. Therefore, produced
The lattice constant of the lithium manganese oxide was measured, and LiMn
_TwoO_FourAnd Li_{1 + X}Al_YMn_2-XYO_FourTo the lattice constant of
Thus, the degree of substitution of Al with Mn can be determined. Soshi
The lithium manganese oxide produced by the method described above
Measurement of the lattice constant of
Is Li_{1 + X}Al_YMn_2-XYO_FourLattice constant with
Than LiMn_TwoO_FourCloser to the lattice constant of
Confirmation that substitution of Al with Mn is not performed properly
it can.

Therefore, what is currently produced by the proposed method and considered to be Li _{1 + X} Al _Y Mn _2-XY O ₄ is actually Li _{1 + X} Al _Y Mn _2-XY O ₄ is a part,
The majority is LiMn ₂ O ₄ , which can be said to be very low in purity. Therefore, it can be said that the effect of improving the charge / discharge cycle characteristics of Li _{1 + X} Al _Y Mn _2-XY O ₄ at a high temperature, that is, a temperature environment equal to or higher than room temperature, is not sufficiently exhibited.

As described above, in the present invention, LiMn
A positive electrode active material excellent in charge-discharge cycle characteristics and a non-aqueous electrolyte battery using the same, wherein Mn is reliably replaced by Al in ₂ O ₄ , and deterioration under high temperature conditions, that is, a temperature condition exceeding room temperature, is suppressed. provide.

FIG. 1 shows a configuration example of a nonaqueous electrolyte secondary battery to which the present invention is applied. This non-aqueous electrolyte battery 1 includes a negative electrode 2
A negative electrode can 3 containing the negative electrode 2, a positive electrode 4, a positive electrode can 5 containing the positive electrode 4, a separator 6 disposed between the positive electrode 4 and the negative electrode 2, and an insulating gasket 7. Can 3
The positive electrode can 5 is filled with a non-aqueous electrolyte.

As the negative electrode 2, lithium metal, a lithium aluminum alloy, or a lithium ion-doped and undoped carbonaceous material in which lithium ions are retained can be used. When lithium metal is used as the negative electrode 2, for example, a metal lithium foil can be used. When a material capable of doping and undoping lithium is used as the negative electrode active material, the negative electrode 2
Is obtained by forming a negative electrode active material layer containing the negative electrode active material on a negative electrode current collector. As the negative electrode current collector, for example, a nickel foil or the like can be used.

As the binder contained in the negative electrode active material layer, a known resin material or the like which is generally used as a binder for the negative electrode active material layer of this type of nonaqueous electrolyte battery can be used.

The negative electrode can 3 houses the negative electrode 2 and serves as an external negative electrode of the nonaqueous electrolyte battery 1.

The positive electrode 4 is formed by forming a positive electrode active material layer containing a positive electrode active material on a positive electrode current collector. As the positive electrode current collector, for example, an aluminum foil or the like is used.

In the present invention, a general formula LiMn ₂ O ₄ (where 0 ≦ X ≦ 0.15, 0 <
Y ≦ 0.3. The general formula Li in which a part of Mn of the spinel-type lithium manganese oxide represented by
A spinel-type lithium manganese oxide represented by _{1 + X} Al _Y Mn _2-XY O ₄ is used.

Formula LiMn ₂ O ₄ (where 0 ≦ X ≦ 0.
15 and 0 <Y ≦ 0.3. The crystal structure is stabilized by substituting Al for Mn of the spinel-type lithium manganese oxide represented by ()). Thereby, since the stability of the crystal is increased even at a high temperature, deterioration at a high temperature, that is, at a temperature environment equal to or higher than room temperature is suppressed, and the charge / discharge cycle characteristics as a positive electrode active material, particularly at a high temperature, that is, a temperature at or above room temperature The charge / discharge cycle characteristics under the environment can be improved.

In the above formula, the excess amount X of lithium in the spinel-type lithium manganese oxide and the M
The substitution amounts Y of n are 0 ≦ X ≦ 0.15 and 0 <Y, respectively.
≦ 0.3. If the excess amount X of lithium in the spinel-type lithium manganese oxide is larger than 0.15, the capacity of the positive electrode active material itself decreases, and a practical capacity cannot be obtained. Further, Mn by a metal element
Is larger than 0.3, the capacity of the positive electrode active material itself decreases, and a practical capacity cannot be obtained. Therefore, by regulating the excess amount X of lithium and the replacement amount Y of Mn by the metal element of the spinel-type lithium manganese oxide to the above values, the charge-discharge cycle characteristics, particularly at high temperatures, It is possible to improve the charge / discharge cycle characteristics in a temperature environment equal to or higher than room temperature.

In the present invention, the aforementioned general formula Li _{1 + X} Al _Y Mn _2-XY O ₄ (where 0 ≦ X ≦ 0.15 and 0 <Y ≦ 0.3. ) Is defined in the range of the following equation.

[0034]

(Equation 7)

The general formula Li _{1 + X} Al _Y Mn _2-XY O ₄ (wherein
0 ≦ X ≦ 0.15 and 0 <Y ≦ 0.3. By defining the lattice constant aÅ of the spinel-type lithium manganese oxide represented by the formula (1) in the range of the above formula, the general formula Li
In the spinel-type lithium manganese oxide represented by Mn ₂ O ₄ , Li _{1 + X} Al _Y in which Mn is surely substituted by Al
Mn _2-XY O ₄ (where 0 ≦ X ≦ 0.15 and 0 <Y
≦ 0.3. ).

As a result, the stability of the spinel crystal structure is improved, and when used as a positive electrode active material, deterioration at high temperatures, that is, at a temperature higher than room temperature, is suppressed. The charge / discharge cycle characteristics in a temperature environment equal to or higher than room temperature are reliably improved.

The positive electrode active material according to the present invention is produced by performing pulverization and mixing using a planetary ball mill. That is, since the positive electrode active material according to the present invention is manufactured by pulverizing and mixing the raw material of the positive electrode active material using a planetary ball mill, the Mn in LiMn ₂ O ₄ is surely obtained.
Is a general formula Li _{1 + X} Al _Y Mn _2-XY O in which is substituted by Al
₄ (where 0 ≦ X ≦ 0.15 and 0 <Y ≦ 0.3), and a spinel-type lithium manganese oxide having a lattice constant within the range of the above formula. Is done. Accordingly, deterioration at high temperatures, that is, at a temperature environment equal to or higher than room temperature, is suppressed, and charge / discharge cycle characteristics, particularly, charge / discharge cycle characteristics at a high temperature, that is, a temperature environment equal to or higher than room temperature, can be improved.

Although the reason for this is not necessarily clear, pulverization and mixing by a planetary ball mill are extremely powerful, and therefore, the general formula Li _{1 + X} Al _Y Mn _2-XY O ₄ (where 0 ≦ X ≦
0.15, and 0 <Y ≦ 0.3. When the spinel-type lithium manganese oxide represented by the formula (1) is manufactured by pulverizing and mixing a Li raw material, an Al raw material, and a Mn raw material with a planetary ball mill, the Li raw material, the Al raw material, and the M
Since the crystal of the n raw material is greatly distorted and the reactivity of the powder is improved, the solid solution of Al in the spinel structure is performed densely. As a result, the stability of the spinel-type crystal structure is improved, so that the deterioration of the positive electrode active material is effectively suppressed, and the charge / discharge cycle characteristics, particularly, the charge / discharge cycle characteristics at high temperatures, that is, in a temperature environment equal to or higher than room temperature, are improved. It is thought that it can be done.

Here, the planetary ball mill used in the present invention will be described. Planetary ball mills are ball mills that use a method in which a sample is ground and mixed in a very short time by using a ball and the wall of a container by applying a stronger centrifugal force to the rotation and orbital motion. In this field, the crusher has excellent crushing ability and mixing ability as compared with the conventional drop crusher and vibration crusher. The principle of the planetary ball mill will be described with reference to the drawings. FIG. 2 is a sectional view schematically showing a main part of the configuration of a planetary ball mill. FIG. 3 schematically shows the operation of the planetary ball mill. FIG. 4 is a sectional view showing a state of a mill pot described later.

As shown in FIG. 2, the planetary ball mill includes a revolving mill body and a mill pot that rotates in the same direction. Then, as shown in FIG. 3, a ball such as alumina is placed as a grinding medium and a sample in a mill pot, and the mill body is revolved while rotating the mill pot as shown in FIG. By doing so, the ball in the mill pot is moved by the centrifugal force generated by the rotation and revolution of the mill pot and the mill main body, and the sample is very finely ground and mixed by the ball and the wall of the mill pot. Further, by doing so, the crystal after the pulverization and mixing by the planetary ball mill has a very large crystal distortion, and exhibits an amorphous-like structure. this is,
When the sample subjected to the planetary ball mill is measured by X-ray diffraction, it can be confirmed that the sample is captured as a broad peak different from the crystalline state. That is, this is considered to be due to the fact that the crystal of the sample reacted due to the mechanical energy of the planetary ball mill.

The above general formula Li _{1 + X} Al _Y Mn
_{2-XYO 4} (where 0 ≦ X ≦ 0.15 and 0 <Y ≦
0.3. In the case of producing the spinel-type lithium manganese oxide represented by
By pulverizing and mixing the raw material and the Mn raw material with a planetary ball mill, the lattice constant a ス ピ of the spinel-type lithium manganese oxide is surely within the range of the following expression.

[0042]

(Equation 8)

Therefore, the general formula Li _{1 + X} Al _Y Mn _2-XY O ₄ (where 0 ≦ X ≦
0.15, and 0 <Y ≦ 0.3. The spinel-type lithium manganese oxide represented by the formula
Since the raw material, Al raw material, and Mn raw material are pulverized and mixed by the planetary ball mill, as described above, deterioration at high temperatures, that is, under a temperature environment equal to or higher than room temperature, is suppressed, and charge / discharge cycle characteristics, particularly at high temperatures, That is, the charge-discharge cycle characteristics in a temperature environment equal to or higher than room temperature are excellent.

The components of the positive electrode mixture other than the spinel-type lithium manganese oxide include a conductive material and a binder.

As the conductive material, a known conductive material that is generally used as a conductive material for the positive electrode active material layer of this type of nonaqueous electrolyte battery, for example, carbon black can be used. Also, as the binder, a known binder usually used as a binder for the positive electrode active material layer of this type of nonaqueous electrolyte battery, for example, polyvinylidene fluoride or the like can be used.

The positive electrode can 5 accommodates the positive electrode 4 and serves as an external positive electrode of the nonaqueous electrolyte battery 1.

The separator 6 separates the positive electrode 4 and the negative electrode 2 from each other, and may be formed of a known material which is generally used as a separator of this type of nonaqueous electrolyte battery. A polymer film is used. Also, from the relationship between lithium ion conductivity and energy density, it is necessary that the thickness of the separator be as small as possible. Specifically, the thickness of the separator is suitably, for example, 50 μm or less.

The insulating gasket 7 is incorporated in the negative electrode can 3 and is integrated. The insulating gasket 7 is for preventing the leakage of the nonaqueous electrolyte filled in the negative electrode can 3 and the positive electrode can 5.

As the non-aqueous solvent of the non-aqueous electrolyte, a non-aqueous solvent conventionally used in various non-aqueous electrolyte secondary batteries can be preferably used. For example, in the case of a lithium ion nonaqueous electrolyte secondary battery, high dielectric constant solvents propylene carbonate, ethylene carbonate, butylene carbonate,
γ-butyrolactone and the like, and low-viscosity solvents such as 1,2-dimethoxyethane, 2-methyltetrahydrofuran, dimethyl carbonate, methylethyl carbonate, and diethyl carbonate can be used.

The electrolyte used for preparing a non-aqueous electrolyte by dissolving the above-mentioned non-aqueous solvent is generally as follows:
Although it depends on the conductive ion species, when the conductive ion species is lithium ion, LiClO ₄ , LiAsF ₆ , Li
PF ₆ , LiBF ₄ , CF ₃ SO ₃ Li and the like can be preferably used. These may be used alone or as a mixture of two or more.

As described above, the non-aqueous electrolyte secondary battery according to the present invention has the general formula Li obtained by pulverizing and mixing the raw material using a planetary ball mill as described above.
_{1 + X} Al _Y Mn _2-XY O ₄ (where 0 ≦ X ≦ 0.15 and 0 <Y ≦ 0.3), and a lattice constant aÅ
Is the same as that of a conventional non-aqueous electrolyte secondary battery except that a spinel-type lithium manganese oxide having a range represented by the following formula is used as a positive electrode active material.

[0052]

(Equation 9)

The cathode active material according to the present invention has the general formula Li
_{1 + X} Al _Y Mn _2-XY O ₄ (wherein 0 ≦ X ≦ 0.15 and 0 <Y ≦ 0.3), a spinel-type lithium manganese oxide having a lattice The constant aÅ is defined in the range of the following equation. Therefore, the positive electrode active material has the general formula LiMn ₂ O ₄ (where 0 ≦ X ≦ 0.15, 0 <
Y ≦ 0.3. ) In which Mn is reliably replaced by Al. Thereby, the cathode active material according to the present invention has a high temperature, that is, deterioration under a temperature environment of room temperature or higher is suppressed, and excellent charge / discharge cycle characteristics, particularly, an excellent charge / discharge cycle at high temperature, that is, a temperature environment of room temperature or higher. This is a positive electrode active material having characteristics.

[0054]

(Equation 10)

Further, the non-aqueous electrolyte battery according to the present invention
The general formula Li described above as an extremely active material _{1 + X}Al_YMn_2-XY
O_Four(Where 0 ≦ X ≦ 0.15 and 0 <Y ≦ 0.3
It is. ) Oxidation of spinel lithium manganese
And the lattice constant aÅ is defined in the range of the following equation.
The positive electrode active material has a
Deterioration under temperature environment above room temperature is suppressed, and it is excellent
Charge-discharge cycle characteristics, especially at high temperatures, that is, temperatures above room temperature
Non-aqueous with excellent charge / discharge cycle characteristics under environmental conditions
Electrolyte battery.

The positive electrode active material and the nonaqueous electrolyte battery 1 are manufactured, for example, as follows.

For the negative electrode 2, first, a negative electrode mixture is prepared by dispersing a negative electrode active material and a binder in a solvent. Next, the obtained negative electrode mixture is uniformly applied on a negative electrode current collector and dried to form a negative electrode active material layer, thereby forming a negative electrode 2.
Is produced. As the binder of the negative electrode mixture, a known binder can be used, and a known additive or the like can be added to the negative electrode mixture.

As the positive electrode 4, first, as a positive electrode active material, a general formula Li _{1 + X} Al _Y Mn _2-XY O ₄ (where 0 ≦ X ≦ 0.
15 and 0 <Y ≦ 0.3. ), And a spinel-type lithium manganese oxide having a lattice constant aÅ in the range of the following formula is produced.

[0059]

[Equation 11]

The general formula Li _{1 + X} Al _Y Mn _2-XY O ₄ (wherein
0 ≦ X ≦ 0.15 and 0 <Y ≦ 0.3. In order to produce a spinel-type lithium manganese oxide having a lattice constant aÅ in the range of the above equation, first, a raw material of the spinel-type lithium manganese oxide is subjected to grinding and mixing using a planetary ball mill. . Here, as the planetary ball mill, for example, BX254 (trade name, manufactured by Fritsch) can be suitably used.

For example, a lithium carbonate (Li ₂ Co ₃ ) powder as a Li raw material, an aluminum hydroxide (Al (OH) ₃ ) powder as an Al raw material, and a manganese carbonate (MnCo ₃ ) powder as a Mn raw material are prescribed. Into a mill pot of a planetary ball mill together with, for example, alumina balls having a diameter of 10 mm. At this time, the mass ratio between the raw material of the spinel-type lithium manganese oxide and the alumina balls is, for example, 1:12. Then, for example, the mill body is revolved while rotating the mill pot under the following conditions, and the mill is crushed and mixed.

Planetary ball mill mixing conditions Revolving radius: 400 mm Revolving speed: 250 rpm Rotating speed: 250 rpm Mixing time: 1 h By operating the planetary ball mill as described above, the centrifugal rotation generated by the rotation and revolving of the mill pot and mill body. The ball in the mill pot is moved by force, and the Li raw material, the Al raw material and the M
The n raw material can be pulverized and mixed very finely, and the crystals of the Li raw material, the Al raw material and the Mn raw material are extremely distorted, and a powder having an amorphous-like structure can be obtained. Thereby, deterioration of the spinel-type lithium manganese oxide at high temperatures, that is, at a temperature environment of room temperature or higher can be suppressed, and charge / discharge cycle characteristics, particularly, charge / discharge cycle characteristics at a high temperature, that is, a temperature environment of room temperature or higher can be improved. be able to.

Although the reason for this is not necessarily clear, pulverization and mixing by a planetary ball mill are very powerful, and for example, the general formula Li _{1 + X} Al _Y Mn _2-XY O ₄ (where
0 ≦ X ≦ 0.15 and 0 <Y ≦ 0.3. When the spinel-type lithium manganese oxide represented by the formula (1) is manufactured by pulverizing and mixing a Li raw material, an Al raw material, and a Mn raw material with a planetary ball mill, the Li raw material, Al
The crystals of the raw material and the Mn raw material are extremely greatly distorted, and the reactivity of the powder is improved, whereby the solid solution of Al into the spinel structure is performed densely. As a result, the stability of the spinel-type crystal structure is improved, so that the deterioration of the positive electrode active material is effectively suppressed, and the charge / discharge cycle characteristics, particularly, the charge / discharge cycle characteristics at high temperatures, that is, in a temperature environment equal to or higher than room temperature, are improved. It is thought that it can be done.

Next, the mixed powder thus produced is fired, for example, in an electric furnace at room temperature and at a temperature of 800 ° C. in the air to obtain a cathode active material of the general formula Li _{1 + X} Al _Y Mn _2-XY
O ₄ (where 0 ≦ X ≦ 0.15 and 0 <Y ≦ 0.3
It is. ) Wherein the lattice constant aÅ is in the range of the following formula.

Next, the positive electrode active material, the binder, and the conductive agent prepared as described above are dispersed in a solvent such as dimethylformamide (DMF) to prepare a positive electrode mixture of a slurry. Next, the positive electrode mixture of the obtained slurry is dried, and the dried product is pulverized to prepare a positive electrode mixture powder. Here, as the binder of the positive electrode mixture, a known binder can be used, and a known additive or the like can be added to the positive electrode mixture.

Next, the positive electrode 4 is produced by pressing the obtained positive electrode mixture powder together with a current collector made of, for example, an aluminum mesh.

The non-aqueous electrolyte is prepared by dissolving an electrolyte salt in a non-aqueous solvent.

The negative electrode 2 is accommodated in the negative electrode can 3, the positive electrode 4 is accommodated in the positive electrode can 5, and a separator 6 made of a porous film made of polypropylene or the like is disposed between the negative electrode 2 and the positive electrode 4. A non-aqueous electrolytic solution is injected into the negative electrode can 3 and the positive electrode can 5, and the negative electrode can 3 and the positive electrode can 5 are caulked and fixed via the insulating gasket 7. The liquid secondary battery 1 is completed.

In the above, when preparing the positive electrode, the positive electrode mixture of the slurry is uniformly applied on the positive electrode current collector.
The positive electrode 4 may be manufactured by drying to form a positive electrode active material layer.

As described above, the nonaqueous electrolyte secondary battery according to the present invention uses a planetary ball mill with a spinel-type lithium manganese oxide as a positive electrode active material when producing a positive electrode active material. A non-aqueous electrolyte secondary battery can be manufactured in the same manner as in the case of manufacturing a conventional non-aqueous electrolyte secondary battery, except that pulverization and mixing are performed.

The shape of the non-aqueous electrolyte secondary battery of the present invention is not particularly limited, and various shapes such as a cylindrical shape, a square shape, a coin shape, and a button shape may be used as necessary. can do.

In the method for producing a positive electrode active material according to the present invention, when producing a spinel-type lithium manganese oxide as a positive electrode active material, a Li raw material, an Al raw material,
The Mn raw material is pulverized and mixed by a planetary ball mill. As a result, the Li raw material, the Al raw material, and the Mn raw material can be made into very fine powders, and the crystal of each raw material can be greatly distorted to have an amorphous-like structure. Then, by firing the mixed powder in this state, the solid solution of Al is ensured, and the general formula LiMn ₂
In O spinel-type lithium manganese oxide represented by _4, can be, Mn, and Al to produce a _{Li 1 + X Al Y Mn 2} -XY O 4 is reliably substituted spinel type lithium manganese oxide . And this Li _{1 + X} Al _Y Mn
The lattice constant aÅ of _2- XYO ₄ can be reliably set within the range of the following expression.

[0073]

(Equation 12)

Therefore, according to the present invention, high temperature, that is,
Deterioration under temperature environment above room temperature is suppressed, and excellent
Producing a positive electrode active material with charge-discharge cycle characteristics
Can be. Also, a method of manufacturing the nonaqueous electrolyte battery according to the present invention
In the method, spinel which is a positive electrode active material
When manufacturing lithium-type lithium manganese oxide
Planetary ball mill for Li raw material, Al raw material and Mn raw material
Crushing and mixing. Thereby, Li raw material, Al
Raw material, Mn raw material can be made into very fine powder,
In addition, the crystal of each raw material is greatly distorted, and amorphous
It can have a slick structure. And this state
By baking the mixed powder of Al, the solid solution of Al
The general formula LiMn_TwoO_FourSpinel-type lithium represented by
In the manganese oxide, Mn and Al are surely substituted.
Is a spinel-type lithium manganese oxide_{1 + X}
Al_YMn_2-XYO_FourCan be produced. And
This Li _{1 + X}Al_YMn_2-XYO_FourThe lattice constant aÅ of
It can be within the following formula range.

[0075]

(Equation 13)

Therefore, according to the present invention, the deterioration of the positive electrode at a high temperature, ie, a temperature environment of room temperature or higher, is suppressed, and excellent charge / discharge cycle characteristics, particularly, excellent charge / discharge characteristics at a high temperature, ie, a temperature environment of room temperature or higher. A nonaqueous electrolyte battery having cycle characteristics can be manufactured.

In the above description, the general formula LiMn ₂
M of spinel type lithium manganese oxide represented by O ₄
General formula Li _{1 + X} Al _Y Mn _2-XY O ₄ in which n is substituted by Al
The method for manufacturing the positive electrode active material represented by and the method for manufacturing the nonaqueous electrolyte battery including the positive electrode active material have been described. However, the present invention is not limited to this, and the general formula Li _{1 + X} M _Y M in which Mn of the spinel-type lithium manganese oxide represented by the general formula LiMn ₂ O ₄ is substituted with the metal element M is used.
n _{2 -XYO 4} (where 0 ≦ X ≦ 0.15 and 0 <Y ≦
0.3. M represents a metal element. The present invention can also be applied to the positive electrode active material represented by the formula (1) and a nonaqueous electrolyte battery provided with the positive electrode active material, and the same effects as described above can be obtained. Here, the metal element M substituting Mn
For example, Al, Mg, Fe, Ni, Cr, C
Metal elements such as o, Zn, Cu, and Ti, or a plurality of these metal elements can be used.

In the manufacturing method according to the present invention, however, the effect of improving the charge / discharge cycle characteristics at high temperatures, that is, under a temperature environment equal to or higher than room temperature, is that the greatest effect is obtained when Al is selected as the metal element M. Can be.

[0079]

The present invention will be described below in more detail with reference to examples.

In the examples, in order to evaluate the positive electrode active material according to the present invention, a battery using Li metal for the negative electrode was used. This is because there is an advantage that the voltage of the battery can be read as it is as a potential with respect to Li. Further, it is possible to eliminate the influence of the charge / discharge characteristics of carbon and to evaluate the characteristics as a positive electrode material purely.

Here, ten types of coin-type batteries of Examples 1 to 5 and Comparative Examples 1 to 5 shown below were produced, and charge / discharge cycle characteristics under a high temperature environment were examined.

In Examples 1 to 5, when producing the positive electrode active material, the raw material of the positive electrode active material was pulverized and mixed using a planetary ball mill, and in Comparative Examples 1 to 5, When producing the positive electrode active material, as a conventional production method, the raw material of the positive electrode active material was ground and mixed using an agate mortar.

Example 1 First, commercially available manganese carbonate (MnCo ₃ ) powder, lithium carbonate (Li ₂ Co ₃ ) powder and aluminum hydroxide (Al
(OH) ₃ ) and powder were mixed using a planetary ball mill. The mixing mass ratio at this time is Li: Al: Mn = 1:
0.05: 1.95. The pulverization and mixing in the planetary ball mill were performed under the following conditions by charging a sample and an alumina ball having a diameter of 10 mm into an alumina pot having a diameter of 100 mm with a mass ratio of sample: alumina ball = 1: 12. Was.

Planetary ball mill mixing conditions Revolution radius: 400 mm Revolution rotation speed: 250 rpm Rotation rotation speed: 250 rpm Mixing time: 1 h The mixed powder obtained above was heated at 800 ° C. in air at normal pressure using an electric furnace. It was fired by heating to obtain a lithium manganese composite oxide powder to be a positive electrode active material.

Next, to 80 parts by weight of the obtained lithium manganese composite oxide powder, 15 parts by weight of graphite as a conductive material and 5 parts by weight of polyvinylidene fluoride as a binder were mixed, and dimethylformamide was appropriately added dropwise. Kneaded well. The kneaded product was dried, and the dried product was further pulverized to obtain a positive electrode mixture powder.

Next, the obtained positive electrode mixture powder was press-formed together with an aluminum mesh as a current collector to prepare a positive electrode.

Next, a metal lithium sheet having a thickness of 1 mm was prepared as a negative electrode.

Next, 1 mol / mol of lithium hexafluorophosphate was added.
1 was dissolved in propylene carbonate to prepare a non-aqueous electrolyte.

Then, the negative electrode 2 was accommodated in the negative electrode can 3, the positive electrode 4 was accommodated in the positive electrode can 5, and a separator made of a porous polypropylene film was disposed between the negative electrode 2 and the positive electrode 4. A non-aqueous electrolyte is injected into the negative electrode can 3 and the positive electrode can 5, and the negative electrode can 3 and the positive electrode can 5 are caulked and fixed via an insulating gasket 7 to have a diameter of 20 mm and a thickness as shown in FIG. A 1.6 mm coin-type nonaqueous electrolyte secondary battery 1 was produced.

Example 2 In preparing a positive electrode active material, manganese carbonate (MnC
o ₃ ) The mixing ratio of the powder, lithium carbonate (Li ₂ Co ₃ ) powder and aluminum hydroxide (Al (OH) ₃ ) powder is represented by L
A positive electrode mixture powder was produced in the same manner as in Example 1 except that i: Al: Mn = 1: 0.15: 1.85, and a coin-type battery was produced.

Example 3 In preparing a positive electrode active material, manganese carbonate (MnC
o ₃ ) The mixing ratio of the powder, lithium carbonate (Li ₂ Co ₃ ) powder and aluminum hydroxide (Al (OH) ₃ ) powder is represented by L
A positive electrode mixture powder was produced in the same manner as in Example 1 except that i: Al: Mn = 1: 0.25: 1.75, and a coin-type battery was produced.

Example 4 In preparing a positive electrode active material, manganese carbonate (MnC
o ₃ ) The mixing ratio of the powder, lithium carbonate (Li ₂ Co ₃ ) powder and aluminum hydroxide (Al (OH) ₃ ) powder is represented by L
A positive electrode mixture powder was produced in the same manner as in Example 1 except that i: Al: Mn = 1.04: 0.05: 1.91, and a coin-type battery was produced.

Example 5 In preparing a positive electrode active material, manganese carbonate (MnC
o ₃ ) The mixing ratio of the powder, lithium carbonate (Li ₂ Co ₃ ) powder and aluminum hydroxide (Al (OH) ₃ ) powder is represented by L
A positive electrode mixture powder was prepared in the same manner as in Example 1 except that i: Al: Mn was set to 1.04: 0.15: 1.81 to prepare a coin-type battery.

Comparative Example 1 When preparing a positive electrode active material, manganese carbonate (MnC
o ₃ ) The mixing ratio of the powder, lithium carbonate (Li ₂ Co ₃ ) powder and aluminum hydroxide (Al (OH) ₃ ) powder is represented by L
Except that i: Al: Mn = 1: 0.05: 1.95 and pulverization and mixing using an agate mortar, a positive electrode mixture powder was produced in the same manner as in Example 1 to produce a coin-type battery. did.

Comparative Example 2 In preparing a positive electrode active material, manganese carbonate (MnC
o ₃ ) The mixing ratio of the powder, lithium carbonate (Li ₂ Co ₃ ) powder and aluminum hydroxide (Al (OH) ₃ ) powder is represented by L
i: Al: Mn = 1.0: 0.15: 1.85,
Except for pulverization and mixing using an agate mortar, a positive electrode mixture powder was prepared in the same manner as in Example 1 to prepare a coin-type battery.

Comparative Example 3 In preparing a positive electrode active material, manganese carbonate (MnC
o ₃ ) The mixing ratio of the powder, lithium carbonate (Li ₂ Co ₃ ) powder and aluminum hydroxide (Al (OH) ₃ ) powder is represented by L
i: Al: Mn = 1.0: 0.25: 1.75,
Except for pulverization and mixing using an agate mortar, a positive electrode mixture powder was prepared in the same manner as in Example 1 to prepare a coin-type battery.

Comparative Example 4 When preparing a positive electrode active material, manganese carbonate (MnC
o ₃ ) The mixing ratio of the powder, lithium carbonate (Li ₂ Co ₃ ) powder and aluminum hydroxide (Al (OH) ₃ ) powder is represented by L
A positive electrode mixture powder was prepared in the same manner as in Example 1 except that i: Al: Mn = 1.04: 0.05: 1.91 and pulverized and mixed using an agate mortar, and a coin-type battery was manufactured. Was prepared.

Comparative Example 5 When preparing a positive electrode active material, manganese carbonate (MnC
o ₃ ) The mixing ratio of the powder, lithium carbonate (Li ₂ Co ₃ ) powder and aluminum hydroxide (Al (OH) ₃ ) powder is represented by L
A positive electrode mixture powder was prepared in the same manner as in Example 1 except that i: Al: Mn = 1.04: 0.15: 1.81 and pulverized and mixed using an agate mortar, and a coin-type battery was manufactured. Was prepared.

<Characteristic Test> Powder X-ray Diffraction In Examples 1 to 5 and Comparative Examples 1 to 5, manganese carbonate (MnCo ₃ ) powder and lithium carbonate ground and mixed by a planetary ball mill or an agate mortar were used. (Li ₂ Co ₃ ) powder and aluminum hydroxide (Al
The powder mixed with (OH) ₃ ) powder was analyzed by powder X-ray diffraction.

Examples 1 to 5 and Comparative Example 1
The lithium manganese composite oxide powder manufactured in Comparative Example 5 was analyzed by powder X-ray diffraction.

Lead Belt Analysis The lithium-manganese composite oxide powders produced in Examples 1 to 5 and Comparative Examples 1 to 5 were subjected to read belt analysis to determine the lattice constant. Table 1 shows the results. 5 and 6 show the relationship between the composition of the lithium manganese composite oxide powder and the lattice constant.

[0102]

[Table 1]

Charge / discharge cycle test The charge / discharge cycle characteristics of the coin-type non-aqueous electrolyte secondary batteries manufactured in Examples 1 to 5 and Comparative Examples 1 to 5 in a 60 ° C. atmosphere are as follows. Was evaluated.
The results are shown in Table 1.

First, each battery was charged at normal temperature at a current density of 0.27 mA / cm ² to 4.2 V, and then continuously charged at 4.2 V until full charge (constant current constant voltage charging). . Next, discharge was performed until the discharge voltage reached 3.7V. Subsequently, in a 60 ° C. atmosphere, the above steps were regarded as one cycle, and this cycle was repeated for 20 cycles, and the capacity retention at 20 cycles was determined. The capacity retention at 20 cycles was obtained as a ratio (%) of the discharge capacity at 20 cycles to the discharge capacity at the first cycle in a 60 ° C. atmosphere.

<Evaluation> As a result of analysis by powder X-ray diffraction,
Manganese carbonate (MnCo ₃ ) powder, lithium carbonate (Li ₂ Co ₃ ) powder, and aluminum hydroxide (Al (OH) ₃ ) powder pulverized and mixed by a planetary ball mill prepared in Examples 1 to 5 For the mixed powder of
It was confirmed that the crystals of the i raw material, the Al raw material, and the Mn raw material had very large distortion, and had an amorphous-like structure.

On the other hand, manganese carbonate (Mn) ground and mixed with the agate mortar prepared in Comparative Examples 1 to 5 was used.
For a mixed powder of a Co ₃ ) powder, a lithium carbonate (Li ₂ Co ₃ ) powder and an aluminum hydroxide (Al (OH) ₃ ) powder, the crystal distortion of the Li raw material, the Al raw material and the Mn raw material is small, and the crystal structure is small. It was confirmed that it maintained.

Examples 1 to 5 and Comparative Example 1
All of the lithium manganese composite oxide powders prepared in Comparative Examples 5 to 5 were prepared according to ISDD card 35-782.
The data and profile of iMn ₂ O ₄ agreed. That is,
Thereby, the lithium manganese composite oxide powders produced in Examples 1 to 5 and Comparative Examples 1 to 5
It was confirmed to be a spinel type lithium manganese oxide.

However, regarding the lattice constants obtained by the lead belt analysis, from Table 1, FIGS. 5 and 6, when preparing the lithium manganese composite oxide powder, each raw material was crushed and mixed using a planetary ball mill. The lattice constants of the lithium manganese composite oxide powders in Examples 1 to 5 were the same as those of the lithium manganese composite oxide powders in Comparative Examples 1 to 5 in which each raw material was ground and mixed using an agate mortar. It can be seen that the values are smaller than those of the samples having the same raw material ratio as compared with the constants. From this, when producing lithium manganese composite oxide powder, it is possible to produce lithium manganese oxide with a smaller lattice constant than before by grinding and mixing each raw material using a planetary ball mill. It can be said that.
This is presumably because, by pulverizing and mixing the raw materials using a planetary ball mill, Al with improved reactivity was finely dissolved in the spinel structure to form crystals with very few defects. The lattice constants of the lithium manganese oxides of Examples 1 to 5 are within the range represented by the following formula, and the lattice constants of the lithium manganese oxides of Comparative Examples 1 to 5 are: It can be seen that it is out of the range represented by the following formula.

[0109]

[Equation 14]

Further, from Table 1, the capacity retention of the coin-type nonaqueous electrolyte secondary batteries of Examples 1 to 5 at the 20th cycle was the same as those of Comparative Examples 1 to 5 having the same composition. It can be seen that it is significantly improved as compared with the non-aqueous electrolyte secondary battery. That is, the capacity retention of the coin-type nonaqueous electrolyte secondary batteries of Examples 1 to 5 at the time of 20 cycles is:
It can be seen that the deterioration of the discharge capacity due to the charge / discharge cycle is suppressed as compared with the coin-type non-aqueous electrolyte secondary batteries of Comparative Examples 1 to 5 having the same composition. From this, when producing lithium manganese composite oxide powder,
By crushing and mixing each raw material using a planetary ball mill, deterioration of the positive electrode active material in a high temperature environment is suppressed, and a decrease in discharge capacity due to a charge / discharge cycle is suppressed,
It can be said that a positive electrode active material and a nonaqueous electrolyte secondary battery having excellent charge / discharge cycle characteristics under a high temperature environment can be manufactured.

[0111]

As described in detail above, the positive electrode active material according to the present invention has the general formula Li _{1 + X} Al _Y Mn _2-XY O
₄ (where 0 ≦ X ≦ 0.15 and 0 <Y ≦), and is composed of a spinel-type lithium manganese oxide having a lattice constant aÅ in the range of the following formula.

[0112]

(Equation 15)

As a result, the positive electrode active material according to the present invention
Deterioration in a high-temperature environment is suppressed, and the charge-discharge cycle characteristics in a high-temperature environment are excellent.

The non-aqueous electrolyte battery according to the present invention includes a negative electrode having lithium, a lithium alloy or a material capable of doping and undoping lithium, a positive electrode, and a non-aqueous electrolyte. formula _{Li 1 + X M Y Mn 2} -XY O 4 ( where 0
≦ X ≦ 0.15, and 0 <Y ≦. M is
Represents a metal element. And a positive electrode active material comprising a spinel-type lithium manganese oxide having a lattice constant a 定 数 in the range of the following formula.

[0115]

(Equation 16)

Thus, the non-aqueous electrolyte battery according to the present invention has excellent charge-discharge cycle characteristics in a high-temperature environment.

The method for producing a positive electrode active material according to the present invention is based on the general formula Li _{1 + X} M _Y Mn _2-XY O ₄ (where 0 ≦ X ≦
0.15, and 0 <Y ≦. M represents a metal element. ) Wherein the lattice constant aÅ is in the range of the following formula, comprising a spinel-type lithium manganese oxide, comprising a pulverization of a Li raw material, a Mn raw material, and a M raw material which are raw materials of the positive electrode active material. And mixing using a planetary ball mill.

[0118]

[Equation 17]

Therefore, according to the method for producing a positive electrode active material according to the present invention, since the raw materials of the positive electrode active material are ground and mixed by using a planetary ball mill, deterioration in a high temperature environment is suppressed, and deterioration in a high temperature environment is suppressed. A positive electrode active material having excellent charge / discharge cycle characteristics can be manufactured.

The method of manufacturing a non-aqueous electrolyte battery according to the present invention comprises the steps of: forming a negative electrode having lithium, a lithium alloy or a material capable of doping / dedoping lithium with a general formula Li _{1 + X}
M _Y Mn _2-XY O ₄ (where 0 ≦ X ≦ 0.15 and 0
<Y ≦. M represents a metal element. And a non-aqueous electrolyte battery comprising a positive electrode containing a positive electrode active material comprising a spinel-type lithium manganese oxide having a lattice constant aÅ in the range of the following formula: The grinding and mixing of the Li raw material, the Mn raw material and the M raw material, which are the raw materials of the positive electrode active material, are performed using a planetary ball mill.

[0121]

(Equation 18)

Therefore, according to the method of manufacturing a nonaqueous electrolyte battery according to the present invention, when producing the positive electrode active material, the raw materials of the positive electrode active material are ground and mixed by using the planetary ball mill. Thus, a non-aqueous electrolyte battery excellent in charge-discharge cycle characteristics in a high-temperature environment can be manufactured.

As described above, according to the present invention, a positive electrode active material comprising a composite oxide of lithium and manganese, which is an inexpensive and resource-rich raw material, has excellent charge-discharge cycle characteristics in a high-temperature environment. It is possible to provide a nonaqueous electrolyte battery including an active material and a positive electrode including the positive electrode active material, and having excellent charge / discharge cycle characteristics even in a high-temperature environment.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a configuration example of a nonaqueous electrolyte battery to which the present invention is applied.

FIG. 2 is a cross-sectional view schematically illustrating a main part of a configuration of a planetary ball mill.

FIG. 3 is a diagram schematically showing the operation of a planetary ball mill.

FIG. 4 is a schematic view showing a state of a mill pot.

FIG. 5 is a characteristic diagram showing a relationship between an Al substitution amount Y of a spinel-type lithium manganese oxide represented by Li _{1 + X} Al _Y Mn _2-XY O ₄ (X = 0) and a lattice constant.

FIG. 6 is a characteristic diagram showing the relationship between the Al substitution amount Y and the lattice constant of a spinel-type lithium manganese oxide represented by Li _{1 + X} Al _Y Mn _2-XY O ₄ (X = 0.04). is there.

[Explanation of symbols]

1 Non-aqueous electrolyte battery, 2 negative electrode, 3 negative electrode can, 4 positive electrode, 5 positive electrode can, 6 separator, 7 insulating gasket, 11 planetary ball mill, 12 mil body, 13 mil pot, 14 balls, 15 samples

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Hideki Sakai 6-7-35 Kita Shinagawa, Shinagawa-ku, Tokyo Inside Sony Corporation (72) Inventor Gen Fukushima 6-35-35 Kita Shinagawa, Shinagawa-ku, Tokyo Sony Corporation F term (reference) 4G048 AA04 AB01 AC06 AD06 5H029 AJ02 AJ14 AK03 AL07 AL12 AM03 AM06 AM07 BJ03 BJ16 CJ02 CJ30 DJ16 HJ02 5H050 AA05 AA19 BA17 CA09 CB07 CB12 GA05 GA10 GA29 HA02

Claims (6)

[Claims] 1. A lattice constant represented by a general formula Li _{1 + X} Al _Y Mn _2-XY O ₄ (where 0 ≦ X ≦ 0.15 and 0 <Y ≦ 0.3). A positive electrode active material comprising a spinel-type lithium manganese oxide wherein aÅ is in the range of the following formula. (Equation 1) 2. A compound of the general formula Li _{1 + X} M _Y Mn _2-XY O _{4 wherein}
0 ≦ X ≦ 0.15 and 0 <Y ≦ 0.3. M represents a metal element. A method for producing a positive electrode active material comprising a spinel-type lithium manganese oxide represented by the following formula:
A method for producing a positive electrode active material, comprising crushing and mixing raw materials using a planetary ball mill. 3. The method for producing a positive electrode active material according to claim 2, wherein M is Al, and a ス ピ of the lattice constant of the spinel-type lithium manganese oxide is represented by the following equation. (Equation 2) 4. A negative electrode having lithium, a lithium alloy or a material capable of doping / dedoping lithium, a positive electrode,
And a non-aqueous electrolyte, wherein the positive electrode has a general formula Li _{1 + X} Al _Y Mn _2-XY O ₄ (wherein
0 ≦ X ≦ 0.15 and 0 <Y ≦ 0.3. A non-aqueous electrolyte battery comprising a cathode active material comprising a spinel-type lithium manganese oxide represented by the following formula: (Equation 3) 5. A negative electrode having lithium, a lithium alloy or a material capable of doping / dedoping lithium, a positive electrode,
A method for producing a non-aqueous electrolyte battery provided with a non-aqueous electrolyte, wherein the positive electrode has a general formula Li _{1 + X MY} Mn _2-XY O ₄ (where 0
≤ X ≤ 0.15 and 0 <Y ≤ 0.3. Also,
M represents a metal element. ) Containing a positive electrode active material composed of a spinel-type lithium manganese oxide, wherein the Li raw material, the M raw material, and the Mn raw material that are the raw materials of the positive active material are ground and mixed using a planetary ball mill. A method for producing a non-aqueous electrolyte battery. 6. The method for producing a non-aqueous electrolyte battery according to claim 5, wherein M is Al, and a lattice constant aÅ of the spinel-type lithium manganese oxide is represented by the following equation. . (Equation 4)