JP2015130316A - Active material for sealed battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrode active material high in capacity and capable of being used as a material constituting a sealed storage battery.SOLUTION: An active material for a sealed battery is an active material used in a sealed battery. The active material includes an alkali metal atom and an oxygen atom, and has a content ratio of an alkali metal atom of 26-75 mass% relative to the whole of the active material. Alternatively, the active material includes an alkali metal atom and a third component atom other than an oxygen atom. Further, the third component atom is at least one atom selected from transition metal elements belonging to Groups 7 to 11 on the periodic table.

Description

The present invention relates to an active material for a sealed battery. More specifically, the present invention relates to an alkali metal compound having a high alkali metal content.

Among power storage devices, the most widely used at present is a lithium ion battery, which is used as a battery for a mobile phone or a notebook computer. However, since the charge / discharge capacity of a lithium ion battery is not sufficient, the development of a new battery having a larger charge / discharge capacity has been demanded. In recent years, a lithium-air battery having a larger theoretical capacity than a lithium ion battery has been demanded. Has attracted attention. A method using an organic electrolyte has been reported for a lithium-air battery (see Non-Patent Document 1).

Zenkaku Okumi, “All about innovative storage batteries”, Industrial Research Committee, 2010, pp. 59-61

However, since the lithium air battery is an air battery, an open battery system is necessary, and there are many problems such as mixing of moisture and carbon dioxide in the atmosphere. For this reason, development of a sealed battery having a larger charge / discharge capacity has been demanded.

This invention is made | formed in view of the said present condition, and has the capacity | capacitance higher than the conventional electrode active material, and it aims at providing the electrode active material which can be used as a material which comprises a sealed storage battery. .

The inventor has studied various electrode active materials that can be used as an active material for a sealed storage battery and has a high capacity, and has focused on the content of alkali metal atoms in the electrode active material. And it discovers that the active material which has high alkali metal content expresses a high capacity | capacitance, and it is possible to comprise a sealed storage battery using this active material, and solves the said subject wonderfully. Thus, the present invention has been achieved.

That is, the present invention is an active material used for a sealed battery, and the active material includes an alkali metal atom and an oxygen atom, and the content ratio of the alkali metal atom is 26 to 75% by mass with respect to the entire active material. It is the active material for sealed batteries characterized by being.
The present invention is described in detail below.
A combination of two or more preferred embodiments of the present invention described below is also a preferred embodiment of the present invention.

The alkali metal atom constituting the active material for a sealed battery of the present invention may be any metal atom classified as an alkali metal, and one or two or more kinds may be used. It is preferably either sodium or potassium. More preferably, it is lithium. When an alkali metal atom made of lithium is used, the active material of the present invention is more suitable as an electrode material.

The sealed battery active material of the present invention is characterized in that the content ratio of alkali metal atoms is as high as 26 to 75% by mass with respect to the whole active material. It is preferable that it is 26-72 mass% with respect to the whole substance. More preferably, it is 26-70 mass%.
Hereinafter, the sealed battery active material of the present invention is also referred to as a high alkali metal content active material.

The sealed battery active material of the present invention may contain one or more third component atoms other than alkali metal atoms and oxygen atoms.
The third component atom is preferably at least one atom selected from transition metal elements belonging to Groups 7 to 11 of the periodic table. More preferably, it is an atom of a transition metal element of Groups 7 to 10 of the periodic table such as Mn, Fe, Co, Ni, etc., and still more preferably any of Fe and Co.

When the sealed battery active material of the present invention includes a third component atom, the ratio of the number of alkali metal atoms to the number of third component atoms (the number of third component atoms / the number of alkali metal atoms) is 0.00001. It is preferable that it is -0.6. Within such a range, the active material for a sealed battery of the present invention has a higher capacity. The ratio of the number of alkali metal atoms to the number of third component atoms is more preferably 0.0001 to 0.4, and still more preferably 0.001 to 0.3.

When the sealed battery active material of the present invention contains a third component atom, the form in which the third component atom exists is not particularly limited, and the third component atom constitutes a composite oxide together with an alkali metal atom and an oxygen atom. The form in which the third component atom is dissolved in the crystal structure of the alkali metal oxide, the simple substance of the third component atom and / or the form in which the compound is included as a catalyst, These may be mixed.
Here, the form of the composite oxide is a form in which the third component atoms are regularly arranged in a certain ratio in the crystal structure of the alkali metal oxide, and the crystal structure of the alkali metal oxide The form in which the third component atom is solid-solved is a form in which the third component atom randomly enters the crystal structure of the alkali metal oxide.
In the case of a complex oxide, a reflection surface completely different from the original alkali metal oxide crystal is produced in the crystal structure due to the influence of the third component atoms regularly arranged in the crystal structure of the alkali metal oxide. As a result, the XRD pattern is completely different from the original alkali metal oxide. On the other hand, the one in which the third component atom is dissolved in the crystal structure of the alkali metal oxide retains the XRD pattern of the alkali metal oxide before the third component atom is dissolved while being amorphized. . In addition, in the case where the third component atom is dissolved in the crystal structure of the alkali metal oxide, the ratio of the third component atom to be dissolved with respect to the alkali metal is not determined, and it can be dissolved in an arbitrary ratio. It is different from the complex oxide. The structure in which the third component atom is dissolved in the crystal structure of the alkali metal oxide can also be referred to as a structure in which the third component atom is doped in the crystal structure of the alkali metal oxide.
In the case where the compound of the third component atom is included as a catalyst, examples of the compound of the third component atom include oxides, sulfides, halides, nitrides and carbides of the third component atom.

The present invention is also a method for producing an active material used in a sealed battery, wherein the production method includes an alkali metal element-containing compound and a third component atom-containing compound other than alkali metal atoms and oxygen atoms. It is also a method for producing an active material for a sealed battery including a step of pulverizing the raw material composition by mechanochemical treatment. Such a production method has a high alkali metal content, and an alkali metal atom, an oxygen atom, and a third component atom other than the alkali metal atom and the oxygen atom (hereinafter also simply referred to as a third component atom). ) Is a simple and preferable method for producing a sealed battery active material having a constituent atom.
The method for producing an active material for a sealed battery of the present invention may include other steps as long as it includes a step of pulverizing the raw material composition by mechanochemical treatment.

The specific method of the mechanochemical treatment is not particularly limited as long as it causes a mechanochemical reaction. Planetary ball mill treatment, bead mill treatment, ball mill treatment or cutter mill treatment, disc mill treatment, stamp mill treatment, hammer mill treatment. Any one or a plurality of milling operations capable of causing a mechanochemical reaction such as jet mill treatment may be mentioned. Among these, the planetary ball mill treatment is particularly preferable because the mechanochemical treatment is sufficiently performed.

When the mechanochemical treatment is performed by a planetary ball mill treatment, it may be performed either by a wet method or a dry method, but is preferably performed by a dry method.
The grinding media used for the planetary ball mill treatment are preferably those having a large mass, specifically 0.00001 g or more. More preferably, it is 0.001 g or more, and still more preferably 0.1 g or more. In addition, as the grinding media, those having 50000 g or less are usually used.
As the grinding media, zirconia balls, agate balls, alumina balls, tungsten carbide balls, iron balls, stainless balls, etc. having a diameter of 0.01 to 500 mmφ can be used.
The grinding media used for the planetary ball mill treatment should be selected by appropriately selecting the optimum number so that the mechanochemical treatment is sufficiently performed in consideration of the volume of the container used for the planetary ball mill treatment and the amount of the compound used for the planetary ball mill. That's fine.

Furthermore, the rotation speed of the planetary ball mill treatment is preferably higher, and specifically, the rotation speed of 10 rpm or more is preferable. More preferably, the number of rotations is 50 rpm or more, and still more preferably the number of rotations is 100 rpm or more. Further, the rotational speed of the planetary ball mill treatment is usually 100000 rpm or less.
In this way, by using the grinding media with a large mass and performing the planetary ball mill treatment at a high rotational speed, the mechanochemical treatment can be sufficiently advanced, and the alkali metal atom, the oxygen atom, and the third component atom are constituted. The active material of the present invention having atoms can be obtained in a higher yield.

The atmosphere in which the milling operation is performed is not particularly limited, and may be performed in any atmosphere such as air or inert gas, but is preferably performed in an inert gas atmosphere from the viewpoint of suppression of impurity generation. As the inert gas, helium, nitrogen, argon or the like can be used.
The time for performing the milling operation is preferably 0.1 to 100000000 hours. More preferably, it is 0.2-10000000 hours, More preferably, it is 0.3-100000 hours.

The alkali metal atom component and the third component atom component used in the mechanochemical treatment step may each be a single element of an atom or a compound such as a complex oxide or an oxide. The metal atom component and the third component atom component are preferably oxides. That is, the mechanochemical treatment step is preferably a step of mechanochemical treatment of the alkali metal oxide and the third component atom-containing oxide.

In addition to the sealed battery active material, an electrode material including the sealed battery active material and an electrode formed using the electrode material are also one aspect of the present invention.
The electrode material (electrode mixture) of the present invention preferably comprises the active material for a sealed battery of the present invention as an essential component and includes a conductive additive and an organic compound, and other components as necessary. May be included.

Examples of the conductive assistant include those described in Japanese Patent Application No. 2013-162663. More preferably, the conductive assistant is graphene, fibrous carbon, carbon nanotube, acetylene black, or metal.
The said conductive support agent has the effect | action which improves the electroconductivity in an electrode, and can use 1 type (s) or 2 or more types.

As a compounding quantity of the said conductive support agent, it is preferable that it is 0.001-300 mass% with respect to 100 mass% of high alkali metal content active materials of this invention in an electrode material (electrode mixture). When the blending amount of the conductive auxiliary is within such a range, an electrode formed from the electrode material of the present invention will exhibit better battery performance. More preferably, it is 0.01-200 mass%, More preferably, it is 0.05-150 mass%.

Examples of the organic compound include polytetrafluoroethylene-containing polymers and polyvinylidene fluoride-containing polymers, as well as those described in Japanese Patent Application No. 2013-162663.

As a compounding quantity of the said organic compound and organic compound salt, it is preferable that it is 0.01-50 mass% with respect to 100 mass% of high alkali metal content active materials in an electrode material. When the compounding amount of these organic compounds and organic compound salts is within such a range, the electrode formed from the electrode material of the present invention will exhibit better battery performance. More preferably, it is 0.01-45 mass%, More preferably, it is 0.1-40 mass%.

When the electrode material of the present invention contains a component other than a high alkali metal content active material, a conductive additive, and an organic compound, the blending amount is 100% by mass of the transition metal solid solution alkali metal oxide in the electrode material The content is preferably 0.01 to 10% by mass. More preferably, it is 0.05-7 mass%, More preferably, it is 0.1-5 mass%.

The electrode of the present invention is made by kneading a high alkali metal content active material with water and / or an organic solvent, a conductive additive or an organic compound as necessary, and forming a paste into a metal foil such as an aluminum foil, a nickel mesh, etc. On the metal mesh, a method of coating and drying so that the film thickness is as constant as possible, or a transition metal solid solution alkali metal oxide, a conductive additive, and an organic compound are kneaded to form a clay. For example, a method of pressure bonding to a metal foil or a metal mesh can be used.
The electrode of the present invention may be used as either a positive electrode or a negative electrode, but is preferably used as a positive electrode. Therefore, the electrode material of the present invention is preferably used as a positive electrode material.

In addition to the active material, electrode material, and electrode of the present invention described above, a battery configured using the electrode of the present invention is also one aspect of the present invention.
When the electrode of the present invention is used as a positive electrode, examples of the negative electrode include those similar to those described in Japanese Patent Application No. 2013-162663, in addition to alkali metals such as lithium, sodium, magnesium, and calcium.

Although it does not restrict | limit especially as electrolyte solution which comprises the battery of this invention, The thing similar to what is described in Japanese Patent Application No. 2013-162663 other than acetonitrile is mentioned.
Examples of the electrolyte constituting the battery of the present invention include LiPF ₆ , LiBF ₄ , LiClO ₄ , LiN (SO ₂ F) ₂ , LiN (SO ₂ CF ₃ ) ₂ , LiN (SO ₂ C ₂ F ₅ ) ₂ , Li ( BC ₄ O ₈ ), LiF, LiB (CN) _{4 and the} like.

When the battery of the present invention uses a separator, the same one as described in Japanese Patent Application No. 2013-162663 can be used.

The high alkali metal content active material of the present invention is a useful compound suitable as an electrode material because it has the above-described configuration and has a high capacity.
Moreover, the manufacturing method of the high alkali metal content active material of this invention is a useful method which can manufacture such a high alkali metal content active material simply.

It is a figure of the XRD measurement result of the solid powder prepared in Preparation Example 1. It is a figure of the XRD measurement result of the solid powder prepared in Preparation Example 2. It is a figure of the XRD measurement result of the solid powder prepared in Preparation Example 3. It is a figure of the XRD measurement result of the solid powder prepared in Preparation Example 4. It is a figure of the XRD measurement result of the solid powder prepared in Preparation Example 5. It is a figure of the XRD measurement result of the solid powder prepared in Preparation Example 6. It is a figure of the XRD measurement result of the solid powder prepared in Preparation Example 7. It is a figure of the XRD measurement result of the solid powder prepared in Preparation Example 8. It is a figure of the XRD measurement result of the solid powder prepared in Preparation Example 9. It is a figure of the XRD measurement result of the solid powder prepared in Preparation Example 10. It is a figure of the XRD measurement result of the solid powder prepared in Preparation Example 11. It is a figure of the XRD measurement result of the solid powder prepared in Preparation Example 12. FIG. 4 is a diagram of the results of a charge / discharge test of Example 1. It is a figure of the result of the charging / discharging test of Example 2. It is a figure of the result of the charging / discharging test of Example 3. It is a figure of the result of the charging / discharging test of Example 4. FIG. 6 is a diagram showing the results of a charge / discharge test of Example 5. It is a figure of the result of the charging / discharging test of Example 6. It is a figure of the result of the charging / discharging test of Example 7. It is a figure of the result of the charging / discharging test of Example 8. It is a figure of the result of the charging / discharging test of Example 9. It is a figure of the result of the charging / discharging test of Example 10. It is a figure of the result of the charging / discharging test of Example 11. It is a figure of the result of the charging / discharging test of Example 12. It is a figure of the result of the charging / discharging test of Example 13. It is a figure of the result of the charging / discharging test of Example 14. 6 is a diagram showing a result of a charge / discharge test of Comparative Example 1. FIG.

The present invention will be described in more detail with reference to the following examples. However, the present invention is not limited to these examples. Unless otherwise specified, “part” means “part by weight” and “%” means “mass%”.

(XRD measurement)
XRD measurement was performed under the following conditions using a fully automatic horizontal X-ray diffractometer (manufactured by Rigaku Corporation, SMART LAB).
CuKα1 line: 0.15406 nm
Scanning range: 10 ° -90 °
X-ray output setting: 45kV-200mA
Step size: 0.020 °
Scan speed: 0.5 ° min ⁻¹ -4 ° min ⁻¹
The XRD measurement was performed in a state where an inert atmosphere was maintained by loading the sample on an airtight sample stage in a glove box.

Preparation Example 1
As raw materials for the positive electrode active material, 2.19 g of lithium oxide (manufactured by Kojundo Chemical Co., Ltd.) and 1.16 g of cobalt oxide (Co ₃ O ₄ , manufactured by Wako Pure Chemical Industries, Ltd.) are placed in a pot for a planetary ball mill. Ball mill mixing (mixing conditions: treatment using 180 10 mmφ zirconia balls at 180 rpm for 180 hours) was performed. All operations were performed in a glove box with a water concentration of 1 ppm or less, which was purged with argon. The XRD measurement result of the obtained solid powder is shown in FIG. Presence of transition metal solid solution Li ₂ O and LiCoO ₂ was confirmed in the obtained solid powder. 67 mg of the obtained solid powder, 77 mg of acetylene black as a conductive additive and 6 mg of polytetrafluoroethylene powder as a binder were mixed in an agate mortar and processed into a clay to obtain a positive electrode mixture. The obtained positive electrode mixture was pressure-bonded to a 60 mg aluminum mesh to obtain a positive electrode.

Preparation Example 2
Same as Preparation Example 1, except that the raw material of the positive electrode active material was changed to 2.43 g of lithium oxide (manufactured by Kojundo Chemical Laboratory Co., Ltd.) and 0.66 g of cobalt oxide (Co ₃ O ₄ , manufactured by Wako Pure Chemical Industries, Ltd.) A solid powder was obtained. The XRD measurement result of the obtained solid powder is shown in FIG. Presence of transition metal solid solution Li ₂ O was confirmed in the obtained solid powder. 51 mg of the obtained solid powder, 60 mg of acetylene black as a conductive assistant, and 6 mg of polytetrafluoroethylene powder as a binder were mixed in an agate mortar and processed into a clay to obtain a positive electrode mixture. The obtained positive electrode mixture was pressure-bonded to a 60 mg aluminum mesh to obtain a positive electrode.

Preparation Example 3
Same as Preparation Example 1 except that the raw material of the positive electrode active material was changed to 2.63 g of lithium oxide (manufactured by Kojundo Chemical Laboratory Co., Ltd.) and 0.36 g of cobalt oxide (Co ₃ O ₄ , manufactured by Wako Pure Chemical Industries, Ltd.) A solid powder was obtained. The XRD measurement result of the obtained solid powder is shown in FIG. Presence of transition metal solid solution Li ₂ O was confirmed in the obtained solid powder. 57 mg of the obtained solid powder, 60 mg of acetylene black as a conductive assistant, and 5 mg of polytetrafluoroethylene powder as a binder were mixed in an agate mortar and processed into a clay to obtain a positive electrode mixture. The obtained positive electrode mixture was pressure-bonded to a 60 mg aluminum mesh to obtain a positive electrode.

Preparation Example 4
Solid material in the same manner as in Preparation Example 1 except that the raw material of the positive electrode active material was changed to 2.30 g of lithium oxide (manufactured by Kojundo Chemical Laboratory Co., Ltd.) and 1.15 g of cobalt oxide (CoO, manufactured by Wako Pure Chemical Industries, Ltd.). A powder was obtained. The XRD measurement result of the obtained solid powder is shown in FIG. Presence of transition metal solid solution Li ₂ O was confirmed in the obtained solid powder. 59 mg of the obtained solid powder, 61 mg of acetylene black as a conductive assistant, and 5 mg of polytetrafluoroethylene powder as a binder were mixed in an agate mortar and processed into a clay to obtain a positive electrode mixture. The obtained positive electrode mixture was pressure-bonded to a 60 mg aluminum mesh to obtain a positive electrode.

Preparation Example 5
The solid of the positive electrode active material was the same as in Preparation Example 1 except that the raw material of the positive electrode active material was changed to 2.94 g of lithium oxide (manufactured by Kojundo Chemical Laboratory Co., Ltd.) and 0.75 g of cobalt oxide (CoO, manufactured by Wako Pure Chemical Industries, Ltd.). A powder was obtained. The XRD measurement result of the obtained solid powder is shown in FIG. Presence of transition metal solid solution Li ₂ O was confirmed in the obtained solid powder. 89 mg of the obtained solid powder, 100 mg of acetylene black as a conductive additive, and 9 mg of polytetrafluoroethylene powder as a binder were mixed in an agate mortar and processed into a clay to obtain a positive electrode mixture. The obtained positive electrode mixture was pressure-bonded to a 60 mg aluminum mesh to obtain a positive electrode.

Preparation Example 6
A solid material was prepared in the same manner as in Preparation Example 1 except that the raw material of the positive electrode active material was changed to 3.09 g of lithium oxide (manufactured by Kojundo Chemical Laboratory Co., Ltd.) and 0.39 g of cobalt oxide (CoO, manufactured by Wako Pure Chemical Industries, Ltd.). A powder was obtained. The XRD measurement result of the obtained solid powder is shown in FIG. Presence of transition metal solid solution Li ₂ O was confirmed in the obtained solid powder. 87 mg of the obtained solid powder, 93 mg of acetylene black as a conductive additive, and 9 mg of polytetrafluoroethylene powder as a binder were mixed in an agate mortar and processed into a clay to obtain a positive electrode mixture. The obtained positive electrode mixture was pressure-bonded to a 60 mg aluminum mesh to obtain a positive electrode.

Preparation Example 7
Solid material in the same manner as in Preparation Example 1 except that the positive electrode active material was changed to 3.10 g of lithium oxide (manufactured by Kojundo Chemical Laboratory Co., Ltd.) and 2.03 g of lithium cobaltate (LiCoO ₂ , manufactured by STREM CHEMICAL). A powder was obtained. The XRD measurement result of the obtained solid powder is shown in FIG. Presence of transition metal solid solution Li ₂ O and LiCoO ₂ was confirmed in the obtained solid powder. 92 mg of the obtained solid powder, 94 mg of acetylene black as a conductive assistant, and 7 mg of polytetrafluoroethylene powder as a binder were mixed in an agate mortar and processed into a clay to obtain a positive electrode mixture. The obtained positive electrode mixture was pressure-bonded to a 60 mg aluminum mesh to obtain a positive electrode.

Preparation Example 8
Solid material in the same manner as in Preparation Example 1 except that the raw material of the positive electrode active material was changed to 3.40 g of lithium oxide (manufactured by Kojundo Chemical Laboratory Co., Ltd.) and 1.12 g of lithium cobaltate (LiCoO ₂ , manufactured by STREM CHEMICAL). A powder was obtained. The XRD measurement result of the obtained solid powder is shown in FIG. Presence of transition metal solid solution Li ₂ O was confirmed in the obtained solid powder. 56 mg of the obtained solid powder, 61 mg of acetylene black as a conductive assistant, and 5 mg of polytetrafluoroethylene powder as a binder were mixed in an agate mortar and processed into a clay to obtain a positive electrode mixture. The obtained positive electrode mixture was pressure-bonded to a 60 mg aluminum mesh to obtain a positive electrode.

Preparation Example 9
Solid material in the same manner as in Preparation Example 1 except that the raw material of the positive electrode active material was changed to 4.95 g of lithium oxide (manufactured by Kojundo Chemical Laboratory Co., Ltd.) and 0.70 g of lithium cobaltate (LiCoO ₂ , manufactured by STREM CHEMICAL). A powder was obtained. The XRD measurement result of the obtained solid powder is shown in FIG. Presence of transition metal solid solution Li ₂ O was confirmed in the obtained solid powder. 86 mg of the obtained solid powder, 100 mg of acetylene black as a conductive assistant, and 10 mg of polytetrafluoroethylene powder as a binder were mixed in an agate mortar and processed into a clay to obtain a positive electrode mixture. The obtained positive electrode mixture was pressure-bonded to a 60 mg aluminum mesh to obtain a positive electrode.

Preparation Example 10
The same procedure as in Preparation Example 1 except that the raw material of the positive electrode active material was changed to 4.23 g of lithium oxide (manufactured by Kojundo Chemical Laboratory Co., Ltd.) and 2.45 g of manganese oxide (MnO _2; manufactured by Wako Pure Chemical Industries, Ltd.). A solid powder was obtained. The XRD measurement result of the obtained solid powder is shown in FIG. Presence of transition metal solid solution Li ₂ O was confirmed in the obtained solid powder. 69 mg of the obtained solid powder, 71 mg of acetylene black as a conductive assistant, and 6 mg of polytetrafluoroethylene powder as a binder were mixed in an agate mortar and processed into a clay to obtain a positive electrode mixture. The obtained positive electrode mixture was pressure-bonded to a 60 mg aluminum mesh to obtain a positive electrode.

Preparation Example 11
Preparation Example 1 except that the raw material of the positive electrode active material was changed to 4.40 g of lithium oxide (manufactured by Kojundo Chemical Laboratory Co., Ltd.) and 2.34 g of α-iron oxide (Fe ₂ O _3; manufactured by Wako Pure Chemical Industries, Ltd.) In the same manner, a solid powder was obtained. The XRD measurement result of the obtained solid powder is shown in FIG. Presence of transition metal solid solution Li ₂ O was confirmed in the obtained solid powder. 45 mg of the obtained solid powder, 47 mg of acetylene black as a conductive additive and 4 mg of polytetrafluoroethylene powder as a binder were mixed in an agate mortar and processed into a clay to obtain a positive electrode mixture. The obtained positive electrode mixture was pressure-bonded to a 60 mg aluminum mesh to obtain a positive electrode.

Preparation Example 12
Solid material in the same manner as in Preparation Example 1 except that the raw material of the positive electrode active material was changed to 4.11 g of lithium oxide (manufactured by Kojundo Chemical Laboratory Co., Ltd.) and 2.01 g of nickel oxide (NiO 2 _, manufactured by Wako Pure Chemical Industries, Ltd.). A powder was obtained. The XRD measurement result of the obtained solid powder is shown in FIG. Presence of transition metal solid solution Li ₂ O and nickel oxide was confirmed in the obtained solid powder. 57 mg of the obtained solid powder, 60 mg of acetylene black as a conductive assistant, and 4 mg of polytetrafluoroethylene powder as a binder were mixed in an agate mortar and processed into a clay to obtain a positive electrode mixture. The obtained positive electrode mixture was pressure-bonded to a 60 mg aluminum mesh to obtain a positive electrode.

Comparative Preparation Example 1
56 mg of lithium cobalt oxide (manufactured by STREM CHEMICAL) as a positive electrode active material, 68 mg of acetylene black as a conductive auxiliary agent, and 7 mg of polytetrafluoroethylene powder as a binder are mixed in an agate mortar, processed into a clay shape, and mixed with the positive electrode An agent was obtained. The obtained positive electrode mixture was pressure-bonded to a 60 mg aluminum mesh to obtain a positive electrode.

The alkali metal content in the solid powder in Preparation Examples 1 to 12 and Comparative Preparation Example 1 is shown in Table 1 below.

Example 1 (Charge / Discharge Test Using a Bipolar Cell)
The charge / discharge test was conducted using a commercially available bipolar cell (HS cell, manufactured by Hosen Co., Ltd.). The working electrode is a positive electrode mixture electrode prepared in Preparation Example 1, the counter electrode is lithium metal, and the electrolyte is 4.0 M LiFSI acetonitrile electrolyte (LiFSI: lithium bisfluorosulfonylimide [LiN (SO ₂ F) ₂ ]) was used. The positive electrode active material was charged at a current density of 13.5 mA / g and then discharged at the same current density. The voltage range was 3.45V-2.0V. The results of the charge / discharge test are shown in FIG. As shown in FIG. 13, it was shown that charging / discharging was possible as a positive electrode active material.

Examples 2 to 12 (Charge / Discharge Test with Bipolar Cell)
A charge / discharge test was performed under the same conditions as in Example 1 except that the positive electrode mixture electrode prepared in Preparation Examples 2 to 12 was used for each working electrode. The results of the charge / discharge test are shown in FIGS. As shown in FIGS. 14-24, it was shown that charging / discharging is possible as a positive electrode active material.

Example 13 (Charge / Discharge Test with Bipolar Cell; Current Density Dependency)
The positive electrode mixture electrode prepared in Preparation Example 1 was used as the working electrode, lithium metal was used as the counter electrode, 4.0 M LiFSI acetonitrile electrolyte (LiFSI: lithium bisfluorosulfonylimide [LiN (SO ₂ F) ₂ ]) was used. The positive electrode active material was charged at various current densities and then discharged at the same current density. The charging depth was 270 mAh / g. FIG. 25 shows the current density dependence of the discharge capacity. As shown in FIG. 25, charging / discharging was possible even at a very high current density exceeding 1000 mAh / g.

Example 14 (Charge / discharge test using a bipolar cell; cycle characteristics)
The positive electrode mixture electrode prepared in Preparation Example 1 was used as the working electrode, lithium metal was used as the counter electrode, 4.0 M LiFSI acetonitrile electrolyte (LiFSI: lithium bisfluorosulfonylimide [LiN (SO ₂ F) ₂ ]) was used. The positive electrode active material was charged at a current density of 45 mA / g and then discharged at the same current density. The charging depth was 200 mAh / g. FIG. 26 shows the dependency of the discharge capacity retention rate on the number of charge / discharge cycles. As shown in FIG. 26, very stable charge / discharge was possible over 15 cycles or more.

Comparative Example 1 (Charge / Discharge Test with Bipolar Cell)
A charge / discharge test was performed under the same conditions as in Example 1 except that the positive electrode mixture electrode prepared in Comparative Preparation Example 1 was used as the working electrode. The results of the charge / discharge test are shown in FIG. As shown in FIG. 27, it was shown that charge / discharge was impossible with the positive electrode mixture electrode prepared in Comparative Preparation Example 1.

Table 2 shows the discharge capacities of the bipolar electrodes of Examples 1 to 12 and Comparative Example 1.

Example 15 (charge depth change)
Charge / discharge under the same conditions as in Example 1 except that the charging depth was gradually increased to 200 mAh / g (first cycle), 270 mAh / g (second cycle), and 325 mAh / g (third cycle). A test was conducted. The obtained discharge capacity results are shown in Table 3. As shown in Table 3, it was shown that charging / discharging was possible at any charging depth.

Examples 16-21 (charge depth change)
Instead of 4.0 M LiFSI acetonitrile electrolyte (LiFSI: lithium bisfluorosulfonylimide [LiN (SO ₂ F) ₂ ]) as the electrolyte, 1.0 M LiTFSI / EC-DEC, 1.0 M LiFSI / EC-DEC, 1 0.0 M LiPF ₆ / EC-DEC, 1.0 M LiPF ₆ / EC-DME, 1.0 M LiBF ₄ / EC-DEC, 1.0 M LiBETI / EC-DEC (LiTFSI: lithium bistrifluoromethanesulfonylimide, LiPF ₆ : lithium hexafluorophosphate, LiBF _4: lithium tetrafluoroborate, LiBETI: lithium bis pentafluoroethane imide, EC: ethylene carbonate, DEC: diethyl carbonate, DME: 1,2-dimethoxyethane) was used Except for Examples A charge / discharge test was performed under the same conditions as in No. 15. The obtained discharge capacity results are shown in Table 3. As shown in Table 3, it was shown that charging / discharging was possible with any electrolyte solution.

Claims (7)

An active material used in a sealed battery,
The active material includes an alkali metal atom and an oxygen atom, and the content ratio of the alkali metal atom is 26 to 75% by mass with respect to the entire active material. The active material for a sealed battery according to claim 1, wherein the active material contains a third component atom other than an alkali metal atom and an oxygen atom. 3. The active material for a sealed battery according to claim 2, wherein the third component atom is at least one atom selected from transition metal elements belonging to Groups 7 to 11 of the periodic table. An electrode material comprising the active material for a sealed battery according to claim 1. An electrode formed using the electrode material according to claim 4. A battery comprising the electrode according to claim 5. A method for producing an active material used in a sealed battery,
The manufacturing method includes a step of pulverizing a raw material composition containing an alkali metal element-containing compound, an alkali metal atom, and a third component atom-containing compound other than an oxygen atom by mechanochemical treatment. For producing an active material.

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