JPH1145716A - Manufacture of electrode for nonaqueous electrolytic battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method of an electrode which can give a high capacity to a battery and suppress internal resistance of the battery. SOLUTION: An active material having composition of Lix Niy Mz O2 (0.8<x<1.5, 0.8<y+z<1.2, 0<=z<0.35; M is an element selected from among Co, Mg, Ca, Sr, Al, Mn, and Fe.) is preserved in gas whose moisture dew point is -20 deg.C or under for a period of time from just after its manufacture to preparation of a mix coating material. Otherwise, the active material is vacuum-dried just before the preparation of the coating material mix. The prepared coating material mix is applied on a current collector.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for manufacturing an electrode for a non-aqueous electrolyte battery, and more particularly, to Li _x Ni _y M
_z O ₂ (where x is 0.8 <x <1.5, y + z is 0.8 <y + z <1.2, z is 0 ≦ z <0.35. M is Co, Mg, Ca, Sr, Al, Mn and F
represents at least one element selected from e. A) an electrode active material layer containing at least an active material having the composition
The present invention relates to a method for producing an electrode for a non-aqueous electrolyte battery having excellent battery characteristics and storage stability.

[0002]

2. Description of the Related Art In recent years, the development of the electronic field has been remarkable, and various devices such as video cameras, liquid crystal cameras, mobile phones, laptop computers, word processors and the like have been developed.
Correspondingly, demands for smaller, lighter, and higher energy densities of batteries used as power supplies for these electronic devices are increasing.

Conventionally, lead-acid batteries and nickel-cadmium batteries have been used in these electronic devices, but these batteries cannot sufficiently meet the demands for miniaturization, weight reduction, and high energy density.

Therefore, a non-aqueous electrolyte battery using a non-aqueous electrolyte in which a lithium salt is dissolved in a non-aqueous solvent has been proposed. This non-aqueous electrolyte battery has already been put into practical use using a carbon material that can be doped or undoped with lithium or a lithium alloy or lithium ion as a negative electrode material and a lithium-cobalt composite oxide as a positive electrode material. Have been.

[0005] This type of non-aqueous electrolyte battery has an operating voltage of three.
Because it is as high as ~ 4V, high energy density is possible,
It has the advantage of less self-discharge and excellent cycle characteristics.

In this non-aqueous electrolyte battery, research and development of active materials and the like have been actively conducted in order to realize further reduction in size, weight, and high energy density. As a positive electrode active material, a lithium-containing composite oxide containing Ni, such as a lithium-nickel composite oxide or a lithium-nickel-cobalt composite oxide, has also been proposed.

For example, Japanese Patent Application Laid-Open No. 9-213330 discloses a method for producing an electrode active material for a non-aqueous electrolyte battery. That is, the same publication discloses that a mixture of a lithium compound, a nickel compound, and an N compound (N is an element other than Li, Ni, and O) is fired using a firing furnace, and a general formula Li _x Ni
_{y N z O 2 (0.8 <} x <1.2,0.8 <y + z <
1.2, 0 ≦ z <0.2), wherein a gas having a carbon dioxide gas content of 0.01% by volume or less and a moisture dew point of −20 ° C. or less is supplied into the firing furnace. It is described that the gas supply rate is supplied at least 5 times the internal volume of the firing furnace within one hour. As described above, the publication discloses the atmosphere at the time of manufacturing the electrode active material, but does not disclose the storage environment of the electrode active material or the special treatment before preparing the mixture.

[0008]

The present inventors have studied the characteristics of nickel-based lithium composite oxides, and found that nickel-based lithium composite oxides have a higher moisture content in air than lithium-cobalt composite oxides. Have a tendency to be easily absorbed. When an active material that has absorbed a large amount of water is used for a battery, there arises a problem that the charge / discharge capacity of the battery is reduced, the internal resistance is increased, and storage stability is deteriorated.

Accordingly, an object of the present invention is to provide a method of manufacturing an electrode for a non-aqueous electrolyte battery which can solve the above-mentioned problems of the prior art and can provide a battery with a high capacity and keep the internal resistance of the battery low. Is to do.

[0010]

Means for Solving the Problems As a result of intensive studies, the present inventors have found that the storage environment after the production of nickel-based lithium composite oxides and the special treatment before the preparation of the mixture have reduced nickel-based lithium composite oxides. The present inventors have found that a composite oxide can be used for preparing a mixture, and have completed the present invention.

That is, the present invention relates to Li _x Ni _y M _z O
₂ (where x is 0.8 <x <1.5, y + z is 0.8
<Y + z <1.2, z is 0 ≦ z <0.35. M
Represents at least one element selected from Co, Mg, Ca, Sr, Al, Mn and Fe. A) preparing an electrode active material mixture paint containing at least an active material having the following composition; and applying the active material mixture paint onto a current collector. Moisture dew point -2 immediately after production until preparation of active material mixture paint
A method for producing an electrode for a non-aqueous electrolyte battery, wherein the electrode is stored in a gas at 0 ° C. or lower.

Further, the present invention relates to Li _x Ni _y M _z O
₂ (where x is 0.8 <x <1.5, y + z is 0.8
<Y + z <1.2, z is 0 ≦ z <0.35. M
Represents at least one element selected from Co, Mg, Ca, Sr, Al, Mn and Fe. A) preparing an electrode active material mixture paint containing at least an active material having the following composition; and applying the active material mixture paint onto a current collector. Characterized in that it is vacuum dried immediately before the preparation of the material mixture paint,
This is a method for producing an electrode for a non-aqueous electrolyte battery.

[0013] The present invention also relates to Li _x Ni _y M _z O
₂ (where x is 0.8 <x <1.5, y + z is 0.8
<Y + z <1.2, z is 0 ≦ z <0.35. M
Represents at least one element selected from Co, Mg, Ca, Sr, Al, Mn and Fe. A) preparing an electrode active material mixture paint containing at least an active material having the following composition; and applying the active material mixture paint onto a current collector. Moisture dew point -2 immediately after production until preparation of active material mixture paint
A method for producing an electrode for a non-aqueous electrolyte battery, characterized in that the electrode is stored in a gas at 0 ° C. or lower, and the active material is vacuum-dried immediately before preparing an active material mixture paint.

In the present invention, the water dew point is -20 ° C.
The following gases are preferably air, nitrogen gas or a rare gas.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Specific embodiments of the present invention will be described. The lithium composite oxide used in the present invention is Li _x Ni _y M _z O ₂ (where x is 0.8 <x <
1.5, y + z is 0.8 <y + z <1.2, z is 0 ≦ z
<0.35. M is Co, Mg, Ca, Sr, A
represents at least one element selected from 1, Mn and Fe. ).

As a method for producing such a lithium composite oxide, for example, LiMetal ³⁺ O ₂ (here, Metal
Is mainly composed of Ni, Co, Mg, Ca, Sr, Al,
(Containing at least one element selected from Mn and Fe) An alkaline water-soluble lithium compound containing an anion that volatilizes during firing and a basic metal salt are reacted in an aqueous medium to obtain a slurry. After drying the slurry, a method of firing the slurry can be exemplified.

The basic metal salt is Metal ²⁺ (OH)
_2-nk (A ⁿ⁻ ) _k · mH ₂ O. Here, Metal ²⁺ contains Ni as a main component and, in some cases, at least one element selected from Co, Mg, Ca, Sr, Al, Mn, and Fe. A ^n- represents a nitrate ion, a chlorine ion, a bromine ion, an acetate ion, an anion of valence n such as carbonate ion (n = 1 to 3). Also, k
Is 0.03 ≦ k ≦ 0.3, and m is 0 ≦ m <2.

The basic metal salt represented by this formula is Metal
²⁺ aqueous solution, about 0.7-0.95 for Metal ²⁺
After adding an equivalent, preferably about 0.8 to 0.95 equivalent of an alkali under a reaction condition of about 80 ° C. or less, the reaction is carried out.
It can be produced by aging at a temperature of from 70 to 70 ° C for from 0.1 to 10 hours and removing by-products by washing with water. Examples of the alkali used here include alkali metals such as sodium hydroxide, alkaline earth metals such as calcium hydroxide, and amines.

A basic metal salt selected from the compounds represented by the above formula and one or more lithium compounds selected from lithium hydroxide, lithium carbonate and hydrates thereof are dissolved in water. The concentration of the reaction solution is 5 to 2
The reaction is carried out in the range of 5% by weight and the reaction temperature is in the range of room temperature to 100 ° C to obtain a slurry. Then, spray drying is performed to improve the uniformity of the shape of the composition.

The dried product is subjected to about 700 to 10 under an oxidizing gas atmosphere containing air, oxygen or ozone.
A lithium composite oxide can be obtained by performing heat treatment in a temperature range of 00 ° C. for about 0.1 to 20 hours and firing.

As another method for producing the lithium composite oxide used in the present invention, a method using a basic metal carbonate obtained from a water-soluble metal compound and a water-soluble lithium compound can be exemplified.

The water-soluble metal compounds used here are nitrates, sulfates, metal chlorides and the like. These water-soluble metal compounds are mainly composed of nickel compounds, Co, Mg, C
A predetermined amount of another water-soluble metal compound may be further mixed so that at least one element selected from a, Sr, Al, Mn and Fe can be blended.

The basic metal carbonate is a precipitate obtained by reacting a mixture of the above water-soluble metal compound with a compound selected from the group consisting of alkali carbonate, alkali bicarbonate, ammonium carbonate and ammonium bicarbonate in water. Further, the precipitate obtained by reacting the reaction system in the presence of sodium hydroxide is filtered and dried. In this case, in order to form a good precipitate, it is preferable to use the carbonate so that the carbonate group is slightly excessive, and it is also important to control the stirring conditions to control the specific surface area of the precipitate.

The basic metal carbonate thus obtained is mixed with a powder of a water-soluble lithium compound such as lithium carbonate and lithium hydroxide in a desired ratio of the metal and Li. The mixture, as a powder, is first heated to 300-500 ° C. in the presence of an inert gas or an oxygen-containing gas. By this heating, only the decomposition of the basic metal carbonate proceeds, and carbon dioxide in the crystal structure is released. This heating is continued until the generation of carbon dioxide gas is substantially completed, and all of the basic metal carbonate is converted into a metal oxide having a large number of fine pores.

When the temperature is further increased after the generation of carbon dioxide has been substantially completed, the molten water-soluble lithium compound penetrates into the fine pores of the metal oxide, and the two are brought into extremely close contact. Here, in the presence of oxygen gas or oxygen-enriched air,
When calcined at a temperature of 00 to 900 ° C., Ni is converted from divalent to trivalent.
And a Li composite oxide is produced.

The basic metal carbonate used here has a large specific surface area (for example, 100 m ² / g or more), so that gas release and formation of micropores after pre-firing are more efficient.

Such a composition (Li _x Ni _{y Mz} O ₂ )
When the active material is left in the air, it tends to absorb water easily, and becomes a state of absorbing a large amount of water during a pulverizing step or the like. In the present invention, the active material is stored in a gas having a water dew point of −20 ° C. or less from immediately after the active material is manufactured until the preparation of the active material mixture. This storage may be performed at room temperature. By this storage, the influence of moisture can be eliminated. If the moisture dew point of the storage gas is higher than -20 ° C, the influence of moisture cannot be completely eliminated, and problems such as a decrease in capacity will occur. The preferred moisture dew point of the gas is -30
It is below ° C. The gas is preferably air, nitrogen gas, or a rare gas, and particularly preferably nitrogen gas or a rare gas.

In the present invention, the active material can be supplied to the positive electrode in a state of low water content by vacuum drying the active material immediately before preparing the active material mixture paint. The degree of vacuum at this time is, for example, 1 Torr or less, particularly 0.1 Torr.
Torr or less is preferable. Drying temperature is 100 ~ 400 ℃
Is preferable, and 150 to 350 ° C. is particularly preferable. Also,
The vacuum drying time is preferably 1 to 48 hours.

Further, in the present invention, the active material is stored in a gas having a water dew point of -20 ° C. or less from immediately after the active material is produced until the preparation of the active material mixture paint, and the active material is mixed with the active material mixture. Vacuum drying may be performed immediately before coating preparation. In this case, the active material can be provided to the positive electrode in a state where the water content is lower.

By taking such a measure, it is possible to avoid a decrease in battery capacity, an increase in internal resistance, and a deterioration in storage stability due to a large amount of water contained in the positive electrode active material, and a battery having a high energy density. Is realized.

In the present invention, at least the above-mentioned active material, conductive agent and binder are slurried in an organic solvent to prepare an electrode active material mixture paint.

The conductive agent used in the present invention is not particularly limited, and may be any conductive material that does not cause a chemical change. As the conductive agent, usually, graphite such as natural graphite (flaky graphite, flaky graphite, etc.), artificial graphite, carbon blacks such as acetylene black, Ketjen black, channel black, furnace black, thermal black, carbon fiber, Examples thereof include conductive fibers such as vapor-grown carbon fibers and metal fibers, and metal powders such as copper, nickel, aluminum, and silver.
Among these, flaky graphite is preferred.

Specific examples of the conductive agent include LF series manufactured by Chuetsu Graphite Industry Co., Ltd., UFG series manufactured by Showa Denko KK, KS series manufactured by LONZA, MICRO CARBO-G series manufactured by Kansai Thermochemical, and Ecos Giken. And Ecos Carbon manufactured by the company.

The amount of the conductive agent varies depending on the specific surface area and the like of the active material, but is preferably 1 to 15% by weight, more preferably 2 to 10% by weight in the dry coating film.

The binder used in the present invention is preferably fluororubber or polyvinylidene fluoride (PVDF). As the fluororubber, vinylidene fluoride-hexafluoropropylene (VDF-HFP) -based copolymer, vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene (VDF-HFP-TFE) -based copolymer,
Vinylidene fluoride-pentafluoropropylene (VDF
-PFP) copolymer, vinylidene fluoride-pentafluoropropylene-tetrafluoroethylene (VDF-P
FP-TFE) copolymer, vinylidene fluoride-perfluoromethylvinyl ether-tetrafluoroethylene (VDF-PFMVE-TFE) copolymer, ethylene-tetrafluoroethylene copolymer, propylene-tetrafluoroethylene copolymer Polymers and the like can be mentioned. Further, a fluorine-containing polymer in which hydrogen in the main chain is substituted with an alkyl group can also be used.

The amount of such a binder to be added depends on the specific surface area of the active material and the conductive agent, the particle size distribution, the strength of the target electrode, and the like, but is preferably 1 to 20% by weight in the dry coating film. 2-15% by weight is preferred.

The organic solvent used for preparing the active material mixture paint is not particularly limited. For example, cyclohexanone, N-methyl-2-pyrrolidone, methyl ethyl ketone, methyl isobutyl ketone, toluene, acetone, methanol, ethanol , 1-propanol, 2-
And propanol. One type of solvent may be used alone, or a plurality of types of solvents may be mixed and used.

In the present invention, the mixing and slurrying of the active material, the conductive agent, the binder and the organic solvent can be carried out by a conventional method. For example, mixing is performed under dry air or under an inert gas by a roll mill method.

The prepared mixture paint is applied on a current collector and dried. The current collector is not particularly limited, and any collector may be used as long as it does not chemically change when the battery is formed. For example, aluminum, aluminum alloy, nickel, stainless steel, titanium and the like are used. In addition to these, those obtained by treating the surface of aluminum or stainless steel with carbon, nickel, or titanium are also used. Particularly, aluminum or an aluminum alloy is preferable. As the shape of the current collector, a film, a net, a porous body, a foam, or the like is used in addition to a foil. The thickness is 1 to 100 μm, and particularly preferably 1 to 50 μm.

The application of the electrode active material mixture paint on the current collector is performed by a reverse roll method, a direct roll method, a blade method, a knife method, an extrusion nozzle method, a curtain method, a gravure roll method, a bar coating method, and a dip method. The coating can be performed by a generally well-known coating method such as a kiss coating method, a squeezing method and the like. Above all, the extrusion nozzle method is preferable. By selecting the solvent composition of the mixture and the drying conditions so that the coating is performed at a speed of 5 to 100 m / min, a good surface state of the coating layer can be obtained.

The drying temperature is preferably 30 to 150 ° C.
0-140 degreeC is more preferable. If the temperature is lower than 30 ° C., drying of the solvent becomes insufficient. If the temperature is higher than 150 ° C., the binder is unevenly distributed on the surface layer of the electrode because the evaporation rate of the solvent is too rapid, so that the electrode characteristics may be deteriorated.

The thickness, length and width of the coating layer are determined by the final size of the battery. It is preferable that the thickness of the coating layer is adjusted after coating by a generally employed calendering process. The processing pressure is 0.2-10t /
cm and a processing temperature are preferably from 10 to 150 ° C.

[0043]

EXAMPLES The present invention will be described more specifically with reference to the following examples, but the present invention is not limited to these examples. [Example 1] Nickel nitrate and cobalt nitrate were converted to Ni /
They were mixed in an aqueous solution so that Co (molar ratio) = 0.8 / 0.2 to form a precipitate, and then dried with a spray drier to obtain substantially spherical particles. Li / Ni / Co (molar ratio) = 1 / 0.8 /
0.2 and baked. The obtained particles were immediately stored at room temperature for one week in air having a water dew point of -50 ° C. Using this lithium composite oxide LiNi _0.8 Co _0.2 O ₂ as an active material, an electrode mixture paint having the following composition was prepared.

(Blending composition) Positive electrode active material: 93 parts by weight of the above-mentioned Li composite oxide Conductive agent: 4 parts by weight of flaky graphite (KS25 average particle size 11 μm manufactured by LONZA) Binder: 3 parts by weight of polyvinylidene fluoride (PVDF) (Elf Alchem Japan KYNAR741) Solvent: 67 parts by weight of N-methyl-2-pyrrolidone (NMP)

3 parts by weight of PVDF was dissolved in 54 parts by weight of NMP to prepare 57 parts by weight of a binder solution. 93 parts by weight of the active material and 4 parts by weight of the conductive material were dry-mixed with a hyper mixer, and the mixture was charged into a pressure kneader. To the mixture was added 13 parts by weight of the binder solution, and the mixture was kneaded for 30 minutes while cooling the jacket of the pressure kneader with water. The kneaded material was taken out, 44 parts by weight of the binder solution and 13 parts by weight of NMP were added, and dissolved with a hyper mixer to obtain an active material mixture paint.

The prepared mixture paint is applied to one side of a current collector made of aluminum foil having a thickness of 20 μm by an extrusion nozzle and dried, and then the mixture is similarly applied to the other side of the current collector and dried. did. This was compression-molded with a roller press machine, cut into a predetermined size, and then the mixture film on one side was peeled off to obtain an electrode of Example 1 having a mixture layer thickness of 65 μm.

Example 2 Nickel nitrate and cobalt nitrate were mixed in an aqueous solution so that Ni / Co (molar ratio) = 0.8 / 0.2, and a precipitate was formed. After drying, substantially spherical particles were obtained. Li / Ni / Co (molar ratio) = 1
/0.8/0.2 and calcined. After leaving the obtained particles in the air for 24 hours, 0.01 T
Vacuum drying was performed under an environment of orr and 200 ° C. for 24 hours.
Using this lithium composite oxide as an active material, a mixture paint for an electrode was prepared in the same manner as in Example 1, and an electrode of Example 2 was produced.

Example 3 Nickel nitrate and cobalt nitrate were mixed in an aqueous solution so that Ni / Co (molar ratio) = 0.8 / 0.2, and a precipitate was formed. After drying, substantially spherical particles were obtained. Li / Ni / Co (molar ratio) = 1
/0.8/0.2 and calcined. The obtained particles were immediately stored at room temperature in an air having a water dew point of -50 ° C for 1 week, and thereafter, were dried in a vacuum dryer at 0.01 Torr and 200 ° C.
Was dried under vacuum for 24 hours. Using this lithium composite oxide as an active material, as in Example 1,
An electrode mixture paint was prepared, and an electrode of Example 3 was produced.

Example 4 Nickel nitrate and cobalt nitrate were mixed in a solution so that Ni / Co (molar ratio) = 0.8 / 0.2. A precipitate was formed and dried with a spray drier. Substantially spherical particles were obtained. Li / Ni / Co (molar ratio) = 1 / 0.8 /
0.2 and baked. The obtained particles were immediately stored in a nitrogen gas having a water dew point of −50 ° C. at normal temperature for one week, and then vacuum-dried in a vacuum drier at 0.01 Torr and 200 ° C. for 24 hours. Using this lithium composite oxide as an active material, an electrode mixture paint was prepared in the same manner as in Example 1, and an electrode of Example 4 was produced.

Comparative Example 1 A nickel-lithium composite oxide synthesized in the same manner as in Example 1 was left in the air for one week until it was used for preparing a mixture for an electrode. Using this lithium composite oxide as an active material as it was, a mixture paint for an electrode was prepared in the same manner as in Example 1, and an electrode of Comparative Example 1 was produced.

(Battery Characteristics) The battery characteristics of each electrode obtained in Examples 1 to 4 and Comparative Example 1 were measured as follows. With respect to each of the obtained electrodes, the positive electrode active material layer was dried to remove residual moisture, thereby producing a circular positive electrode having a diameter of 15.5 mm. Separately, as a negative electrode, 1.85 mm-thick metallic lithium was punched into a 15.5 mm diameter. Then, a non-aqueous electrolyte was prepared by dissolving LiPF ₆ at a concentration of 1 mol / liter in a 1: 1 (volume ratio) mixture of ethylene carbonate and dimethyl carbonate.

Using the non-aqueous electrolyte, the positive electrode and the negative electrode, and further using a polypropylene thin film separator, a negative electrode cup, a positive electrode can, and a gasket, the diameter 2 shown in FIG.
A coin-type battery of 0 mm × 2.5 mm thickness was produced. In FIG. 1, this coin-type battery has a positive electrode (4) housed in a positive electrode can (6) and a negative electrode housed in a negative electrode cup (1).
(2) and (2) are laminated via a separator (3)
(6) and the negative electrode cup (1) are caulked via a gasket (5) and are hermetically sealed. The illustration of the current collector is omitted.

With respect to the battery thus manufactured,
Charging was performed under the conditions of a charging voltage of 4.2 V, a charging current of 1 mA, and a charging time of 20 hours, a discharging current of 1 mA, and a final voltage of 3.
Discharge was performed under the condition of 0 V, and the charge / discharge capacity was determined. Table 1 shows the results.

[0054]

[Table 1]

As shown in Table 1, in the batteries using the electrodes of Examples 1 to 4, the charge / discharge capacity was high, and the discharge capacity at the fifth time was high.
Excellent cycle characteristics. On the other hand, in Comparative Example 1, the charge / discharge capacity is low, and particularly, the discharge capacity at the fifth time is low.

[0056]

As described above, according to the present invention, an active material having a composition of Li _x Ni _y M _z O _{2 having} a low water content can be provided to an electrode. Therefore, when the electrode for a non-aqueous electrolyte battery manufactured by the method of the present invention is used, a high capacity can be provided to the battery and the internal resistance of the battery can be suppressed low. INDUSTRIAL APPLICABILITY The present invention contributes to improvement of battery characteristics and storage stability of a non-aqueous electrolyte battery.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a coin-type battery for measuring battery characteristics.

[Explanation of symbols] (1) Negative cup (2) Negative electrode (3) Separator (4) Positive electrode (5) Gasket (6) Positive electrode can

Claims (4)

[Claims] 1. Li _x Ni _y M _z O ₂ (where x is 0.8 <x <1.5, y + z is 0.8 <y + z <1.
2, z is 0 ≦ z <0.35. M is Co, Mg,
It represents at least one element selected from Ca, Sr, Al, Mn and Fe. A) preparing an electrode active material mixture paint containing at least an active material having the following composition; and applying the active material mixture paint onto a current collector. A method for producing an electrode for a non-aqueous electrolyte battery, comprising storing in a gas having a water dew point of −20 ° C. or less from immediately after production to preparation of an active material mixture paint. 2. Li _x Ni _y M _z O ₂ (where x is 0.8 <x <1.5, y + z is 0.8 <y + z <1.
2, z is 0 ≦ z <0.35. M is Co, Mg,
It represents at least one element selected from Ca, Sr, Al, Mn and Fe. A) preparing an electrode active material mixture paint containing at least an active material having the following composition; and applying the active material mixture paint onto a current collector. A method for producing an electrode for a non-aqueous electrolyte battery, comprising vacuum drying immediately before preparing a material mixture paint. 3. Li _x Ni _y M _z O ₂ (where x is 0.8 <x <1.5, y + z is 0.8 <y + z <1.
2, z is 0 ≦ z <0.35. M is Co, Mg,
It represents at least one element selected from Ca, Sr, Al, Mn and Fe. A) preparing an electrode active material mixture paint containing at least an active material having the following composition; and applying the active material mixture paint onto a current collector. Immediately after production until preparation of the active material mixture paint, storing in a gas having a water dew point of −20 ° C. or less, and drying the active material under vacuum immediately before preparation of the active material mixture paint. A method for producing an electrode for a water electrolyte battery. 4. The method for producing an electrode for a non-aqueous electrolyte battery according to claim 1, wherein the gas having a water dew point of −20 ° C. or less is air, nitrogen gas, or a rare gas. .