JP2001202948A - Active material for positive electrode and method of fabrication - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an active material for positive electrode, capable of making the output and energy density of a secondary battery higher with a nonaqueous electrolyte. SOLUTION: The active material for positive electrode is composed of secondary particles of a sintered porous body, formed by uniting primary particles comprising metal oxides containing lithium such as lithium cobaltate, lithium nickelate, lithium manganate or the like. As the dimension of the active material of a secondary particle 40, the ratio of width w to height h is 2 or larger and the ratio of length 1 to height h is 2 or larger.

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 for a secondary battery, a method for producing the same, and a composition and a secondary battery using the positive electrode active material for a secondary battery. The present invention relates to a positive electrode active material for a non-aqueous electrolyte secondary battery, a method for producing the same, and a non-aqueous electrolyte secondary battery.

[0002]

2. Description of the Related Art In recent years, as electronic devices have become more portable,
Non-aqueous electrolyte secondary batteries such as lithium ion batteries have been put to practical use in order to meet the demands for smaller size, lighter weight, and higher energy density. The non-aqueous electrolyte secondary battery has, for example, a structure as shown in FIG. In the battery case 10, wound electrodes constituting the positive electrode 11 and the negative electrode 12, respectively, are accommodated. Between the positive electrode 11 and the negative electrode 12,
A separator 13 is provided, and the separator 13 is impregnated with an organic electrolyte. The positive electrode 11 and the negative electrode 12
Each has a structure in which an active material is provided to a core material.

[0003] Such a non-aqueous electrolyte secondary battery can be applied to, for example, a hybrid electric vehicle. However, batteries used in hybrid electric vehicles and the like generally require higher output, and conventional non-aqueous electrolyte secondary batteries do not sufficiently meet the demand. In general, a non-aqueous electrolyte secondary battery has a relatively high energy density, but as the output increases, the energy density tends to decrease significantly. In a non-aqueous electrolyte secondary battery, it is generally difficult to achieve both higher output and higher energy density. To solve this problem, WO 99/33129 requires at least 1000
Although a secondary battery having an output of W / kg and an energy density of 9 W · hr / kg is proposed, a secondary battery having an even higher output and energy density is desired.

[0004]

SUMMARY OF THE INVENTION One object of the present invention is to provide a positive electrode active material, a method for producing the same, and a positive electrode active material which can increase the output and energy density of a secondary battery, especially a non-aqueous electrolyte secondary battery. It is to provide a material composition.

A further object of the present invention is to provide a secondary battery, particularly a non-aqueous electrolyte secondary battery, which can exhibit higher output and higher energy density.

[0006]

SUMMARY OF THE INVENTION While a consumer lithium ion battery (eg, 18650 standard) has a relatively high energy (capacity) density, the relationship between its power density and energy density is shown in FIG. Something like
That is, as the output increases, the energy density decreases significantly. The equivalent series resistance (hereinafter abbreviated as ESR) is usually about 30 mΩ (no PTC). With such a high ESR, a higher output cannot be obtained. On the other hand, the present inventors have improved the positive electrode active material to reduce the ESR and obtain a nonaqueous electrolyte secondary battery having an excellent relationship between output density and energy density as shown in FIG. Reached.

Thus, according to the present invention, there is provided a positive electrode active material for a secondary battery, wherein the positive electrode active material is a particle of a porous sintered body in which particles made of a metal oxide are bonded, and the width of the positive electrode active material with respect to the height is smaller. The ratio is 2 or more, and the ratio of the length to the height is 2 or more.

In the present specification, “height”, “width”, and “length” refer to the positive electrode active material particles 40 as shown in FIG.
H, w and l in three directions perpendicular to each other
Are respectively shown. That is, the height h indicates the particle size in the z-axis direction, the width w indicates the particle size in the x-axis direction, and the length 1 indicates the particle size in the y-axis direction. Among these dimensions, the height h is the shortest, and therefore, the height h can be said to be the thickness of the particle. In the positive electrode active material particles according to the present invention, the ratio of the width w to the height h (w /
h) is 2 or more, and the ratio of the length l to the height h (l /
h) is 2 or more.

[0009] In a preferred embodiment of the present invention, the positive electrode active material is in a scale shape. The height (thickness) of the active material according to the present invention is preferably 40 μm or less. Furthermore, the active material according to the invention preferably has a particle size of 5 μm to 600 μm. The particle size can be determined by measurement with a laser diffraction particle size distribution device.

In a preferred embodiment of the present invention, the metal oxide of the active material is lithium cobalt oxide (eg, LiCo
O ₂ ), lithium nickelate (eg, LiNiO ₂ ),
It is a metal oxide (lithium composite oxide) containing lithium such as lithium manganate (eg, LiMnO ₂ ).

Further, according to the present invention, there is provided a positive electrode active material composition for a non-aqueous electrolyte secondary battery containing the above active material and conductive carbon. The content of the active material in the composition is desirably 1% by weight or more.

Further, according to the present invention, there is provided a non-aqueous electrolyte secondary battery including the above-mentioned active material in a positive electrode.

On the other hand, the present invention provides a method for producing the above-mentioned positive electrode active material for a secondary battery, which method comprises crushing a material obtained by bonding a metal oxide powder to an appropriate size. And a step of obtaining particles having a width to height ratio of 2 or more and a length to height ratio of 2 or more, and firing the obtained particles.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION The positive electrode active material according to the present invention has, for example, a sintered structure as shown in FIG. That is,
The positive electrode active material according to the present invention takes the form of secondary particles formed by bonding a large number of small primary particles (particles of metal oxide). Since the primary particles are joined by a plane, the electrical conductivity of the active material is increased. Further, the sintered structure is porous, and voids exist between the primary particles. When a positive electrode of a secondary battery is formed, conductive carbon or the like enters such voids, and as a result, electrical conductivity can be improved. On the other hand, conventionally, the positive electrode plate has been constituted by simply assembling primary particles. Examples are shown in FIGS. 6A and 6B. FIG. 6A shows an example when the particle size is small, and FIG. 6B shows an example when the particle size is large. Here, the primary particles are merely collected and not bonded (sintered). The prior art attempts to improve the electrical conductivity of the electrode plate by covering each of the primary particles with conductive carbon. However, in this case, the ESR
Becomes as large as several tens mΩ.

As described above, the positive electrode active material according to the present invention comprises:
Since it has the form of secondary particles in which small primary particles are surface-bonded to each other and has a porous structure capable of filling conductive carbon in voids between the primary particles, it can have conductivity several times better than conventional ones.

In the positive electrode active material of the present invention which is a porous sintered body, the particle size of the bonded primary particles (particles of metal oxide) can be 0.1 to 100 μm, and 1 to 40 μm.
μm is preferred. The shape of the primary particles is not particularly limited, and may be spherical, massive, polyhedral, plate-like, or the like. As the material of the primary particles, an appropriate material can be selected according to the application. For example, in the case of a non-aqueous electrolyte secondary battery, a lithium composite oxide such as lithium cobaltate, lithium nickelate, and lithium manganate can be preferably used as the primary particle material. The secondary particles may be composed of only the primary particles, or may contain additives such as a sintering aid in addition to the primary particle material.

The shape of the positive electrode active material particles according to the present invention is also important. That is, in the positive electrode active material particles according to the present invention, the ratio of the width to the height is 2 or more, and the ratio of the length to the height is 2 or more. That is, the particles according to the present invention have a shape with a high aspect ratio. On the other hand, for shapes with a low aspect ratio, such as lumps and spheres,
The problem that there are many areas where conductive carbon cannot enter,
In addition, there arises a problem that the electrode plate cannot be manufactured because the particle size becomes too large.

In the positive electrode active material particles according to the present invention, the ratio of the width to the height can be, for example, 2 to 10, and preferably 2 to 5. The ratio of the length to the height can be, for example, 2 to 10, and preferably 2 to 5. In particular, the particles according to the present invention preferably have a scaly shape, and the height (thickness) thereof is preferably 40 μm or less, more preferably 30 μm or less. FIG. 7 shows an example of the surface of the positive electrode plate using the flaky particles according to the present invention. In the figure, the shape of the flaky particles can be seen. When the positive electrode active material has such a shape with a high aspect ratio, the filling rate of conductive carbon can be increased, and the application of particles to the substrate in the active material application step can be facilitated. Furthermore, such a shape can increase the weight ratio of the active material in the positive electrode.

Further, the positive electrode active material particles according to the present invention have
It preferably has a particle size distribution substantially in the range of μm to 600 μm. FIG. 8 shows an example of the particle size distribution of the particles according to the present invention. This distribution was measured by a laser diffraction particle size distribution analyzer. The measurement method follows a usual method. In this distribution, the minimum value of the particle diameter (particle size) is about 5 μm, and the maximum value is about 600 μm. When the particle size falls below 5 μm, the effect as secondary particles as a sintered body decreases, and the effect approaches the primary particles. On the other hand, when the particle size exceeds 600 μm,
It becomes difficult to prepare a high-density slurry using it, or it becomes difficult to apply particles to a substrate.

As the active material in the positive electrode of the nonaqueous electrolyte secondary battery, only the above-described porous sintered body may be used, or the above-described porous sintered body (secondary particles) and metal oxide particles (secondary particles) may be used. And primary particles). When a mixture is used, the content of the secondary particles in the mixture is, for example, preferably from 5% by weight to 95% by weight, and more preferably from 10% by weight to 9% by weight.
5% by weight is more preferred.

For example, the positive electrode may be made of the above-mentioned positive electrode active material, a conductive auxiliary comprising conductive carbon such as graphite or carbon black, a binder such as polyvinylidene fluoride or polytetrafluoroethylene, and if necessary, N-methyl- Composition (mixture) obtained by mixing an organic solvent such as 2-pyrrolidone
On a current collector made of a metal such as aluminum, titanium, and platinum, followed by drying.
In the mixture, the content of the positive electrode active material according to the present invention is:
1% by weight or more, preferably 10 to 5%.
0% by weight.

On the other hand, other elements such as a negative electrode, a separator, and an electrolytic solution can be prepared according to ordinary techniques. For example, the negative electrode is obtained by mixing a negative electrode active material such as carbon, a binder such as polyvinylidene fluoride (PVDF) and polytetrafluoroethylene, and an organic solvent such as N-methyl-2-pyrrolidone if necessary. The resulting composition (mixture)
It can be obtained by coating and drying on a current collector made of a metal such as aluminum, titanium, and platinum. In addition, a polypropylene film or the like can be used for the separator, and the electrolyte solution is an organic solvent such as ethylene carbonate or dimethyl carbonate in which LiPF ₆ , LiC ₄
A solution in which an electrolyte such as F ₉ SO ₃ is dissolved can be used.

The positive electrode active material according to the present invention is obtained by crushing a material obtained by bonding metal oxide powder to an appropriate size,
It can be produced by obtaining particles having a width to height ratio of 2 or more and a length to height ratio of 2 or more, and then firing the obtained particles. Specifically, a slurry containing metal oxide powder, a binder, and a solvent was applied to a flat substrate, dried, and the resulting film material was peeled from the substrate, and then peeled. By crushing the film material, particles having a width to height ratio of 2 or more and a length to height ratio of 2 or more can be obtained. On the other hand, by cutting a molded body made of a mixture of a thermoplastic resin and a metal oxide powder with a predetermined cutting amount, the ratio of the width to the height as a facet is 2 or more, and the ratio of the length to the height is Two or more particles can be obtained. In addition, a slurry containing a metal oxide powder, a binder, and a solvent is applied on an expanded metal coated with a surfactant, and after drying, the applied surface is tapped to peel and crush the film. Thus, necessary particles can be obtained. The particle size of the metal oxide powder used in such a method is preferably from 2.5 to 40 μm.
The particles thus obtained are, for example, 850 to 10
By firing at a temperature of 00 ° C., the positive electrode active material according to the present invention can be obtained. Hereinafter, the present invention will be described in more detail with reference to specific examples.

[0024]

EXAMPLES A positive electrode active material can be prepared by any of the following three methods.

Production Method 1 A lithium cobaltate powder (primary particles) having a maximum particle size of about 40 μm, a solvent, and a binder were mixed to prepare a slurry. The solvent is not particularly limited,
In the case of an organic solvent, a solvent having a very high volatility is not preferred because there is a problem in the stability of the subsequent slurry. Any binder can be used as long as it decomposes at a temperature of 900 ° C. or lower. In this example, water was used as a solvent, and polyvinyl alcohol (PVA) was used as a binder. LiCoO ₂ powder was added to a solution of PVA dissolved in water and stirred to obtain a slurry. At this time, the viscosity of the slurry was adjusted to an appropriate value so that a film of 40 μm or less could be obtained after coating and drying. A suitable viscosity range is
It was 1000-7000 cps (measured value with a B-type viscometer).

The obtained slurry is applied to a substrate by a usual method such as a spray method or a comma method, and then dried. If the coating is performed by these methods, the film thickness after drying can be controlled to 40 μm or less. Next, the film-like material obtained after drying is separated from the substrate.
In this embodiment, the comma-type coating was performed, and after drying, the film material was sucked while feeding the substrate by a vacuum cleaner or a dust collector. By selecting the substrate, the film thickness can be controlled to be 40 μm or less after drying, and the peeling after drying can be facilitated. In this example, a substrate wound around a roll was used. At the time of use, the substrate was sent out from the roll to perform coating, and after peeling, the substrate was wound around the roll again. In this way, the substrate
Can be used repeatedly.

The thickness of the film material is 40 μm or less, for example, 20 to 30 μm, and when the film material is peeled off from the substrate by a vacuum cleaner or a dust collector, several mm to
Crushed to a size of several tens of mm. Thus, foil-like or scale-like particles having a thickness of 40 μm or less can be obtained. The obtained particles are placed in a crucible, and 850 to 1
It is fired in an air atmosphere at 000 ° C. For the crucible, it is necessary to use a material that does not react at the temperature. In this example, an alumina crucible was used. In the firing step, the binder is decomposed and disappears, and the primary particles such as LiCoO ₂ are bonded not by the binder but by crystallographic planes. At this time, the temperature and time are controlled so that the grain growth of the primary particles, adhesion between the particles, and bonding do not proceed excessively. It is desirable that the primary particles are bonded only on a certain surface, and that the shape of the primary particles hardly changes. In the present embodiment, an ideal bonding mode was obtained by performing calcination at 920 ° C. for 4 to 16 hours.

Next, the obtained sintered body is classified by a classification system such as a vibration sieve. Since the sintered body is brittle, it is desirable to devise it so that it will not be crushed too much. In this example, a small amount of glass beads or a rubber liner was put in a vibrating sieve, and pulverization and classification were performed simultaneously. Yield is 10
It was 0%. According to this method, it was possible to classify into a predetermined size, and the yield was 100% in principle, and it was considered that the best result could be obtained. The particle size distribution of the active material obtained by pulverizing and classifying with a 150 μm mesh was as shown in FIG. FIG. 9 shows the result of observing the obtained active material with an electron microscope.

The active material according to the present invention thus produced has a scale-like shape, its thickness is controlled to 40 μm or less, and its particle size is also controlled to a predetermined range. Here, by changing the mesh size of the vibrating sieve at the time of pulverization and classification, it is possible to produce various sizes. On the other hand, from the viewpoint of ease of preparation of the slurry for the positive electrode plate, reproducibility of the packing density, stability of the coating process, and battery performance, 5 μm was measured with a laser diffraction particle size distribution analyzer.
It was found that those distributed in the range of m to 600 μm were preferable.

Production method 2 Mix 1% to 40% by weight of non-chlorinated thermoplastic resin pellets such as polyethylene and polypropylene while heating with the intercalation compound active material such as lithium cobalt oxide as the balance, knead and extrude under pressure. By φ60mm × 1
A briquette of about 50 mm is obtained. The resulting briquette is cut with a carbide cutting tool of a nitride ceramic such as cermet. The cutting depth is set to 20 to 80 μm, the feed rate of the cutting tool is appropriately selected, and the cutting face is prepared using a lathe. Prevents metal contamination at the time of cutting with a cutting tool such as a cermet, and prevents metal components from remaining in an active material to be fired later. In addition, compressed air whose dew point is controlled at −60 ° C. (7 to 10 atm) is supplied to the primary side between the cutting edge of the cutting tool and the briquette at the time of cutting, and compressed air of about −20 ° C. which is discharged from the secondary side. Spray. This prevents contamination due to components of the commonly used cutting oil.

The lathe cutting tool produced by the above process is
Firing is performed in the same manner as in the above-mentioned production method 1, and then pulverization and classification are performed in the same manner to obtain a positive electrode active material.

Manufacturing Method 3 Nickel expanded metal (lath) (opening size 1.5) used as a current collector of a small secondary battery for consumer equipment
× 0.75 to 3 × 1.5 mm (0.05 t)) and prepare a hoop having a width of 300 mm.

In an in-line apparatus, the non-ionic surfactant is spray-coated on the expanded metal and dried. Next, a slurry containing lithium cobaltate powder, a solvent, and a binder is applied to the expanded metal. Although the above-mentioned PVA-containing aqueous slurry may be used, in this method, the organic solvent slurry is more suitable. Therefore, it is preferable to use a binder soluble in an organic solvent. The method of applying the slurry to the expanded metal may be a converse method or a roll bar coater method when the viscosity of the slurry is low in order to make the dried film thin. Upon application, the slurry becomes
A film is formed at the opening of the expanded metal. Since the thickness of the film is determined by the balance between the surface tension and the cohesive force due to the properties of the slurry component and the nonionic surfactant on the expanded metal, the film thickness is adjusted taking into account these factors. Next, the applied expanded metal is dried, and the film is peeled off by intermittently hitting the application surface with a rubber hammer or the like provided in the transport path. At this time, the film separated by the dust collector may be collected. The obtained flake-shaped particles are fired in the same manner as in the above-mentioned production method 1, and then pulverized and classified in the same manner to obtain a positive electrode active material. In this method, the flakes can be defined and prepared to a certain size before firing.

Manufacture of Positive Electrode Plate The active material according to the present invention manufactured by the above-described method and the primary particles as its raw material are mixed, and this mixture is mixed with conductive carbon, a binder (for example, PVDF), and N- A slurry is obtained by kneading with an organic solvent such as methyl-2-pyrrolidone (hereinafter abbreviated as NMP). Scaly,
The higher the addition rate of the active material, which is a secondary particle having a relatively large particle diameter to which the primary particles are bonded, the more difficult it is to disperse during kneading than to the primary particles. However, a process in which the binder is dissolved in an organic solvent to obtain a solution, the active material and the conductive carbon are charged into the solution, and a process in which a small amount of the organic solvent is charged and kneaded into the obtained mixture is repeated a plurality of times. By preparing a kneaded mixture and mixing the obtained kneaded mixture with an organic solvent, a high-density slurry equivalent to kneading only the primary particles can be prepared. The obtained slurry is subjected to steps such as application, compression, cutting, and winding according to a conventional method to obtain a positive electrode plate for a non-aqueous electrolyte secondary battery. As a core material for applying the slurry, a metal foil such as an aluminum foil, a titanium foil, and a platinum foil can be used.

Manufacture of Nonaqueous Electrolyte Secondary Battery The slurry prepared as described above is applied to a core material of an aluminum foil, and subjected to compression, cutting, winding and the like as usual to obtain a positive electrode plate. On the other hand, carbon is used as a negative electrode active material, and is used as a binder (for example, PVDF) and NM.
A slurry is obtained by kneading with P, and the obtained slurry is applied to a core material made of a copper foil or a nickel foil, and a negative electrode plate is obtained through steps such as compression, cutting, and winding as usual. As the electrolytic solution, one obtained by dissolving LiPF ₆ at a concentration of 1 mol / l in a mixed solvent of ethylene carbonate and dimethyl carbonate is used. A porous polypropylene film is used for the separator. A positive electrode plate and a negative electrode plate are stacked with a separator in between, and wound to form a spiral electrode body. This is filled in a battery case, and the positive and negative electrode leads are connected to each other. Then, the electrolyte is injected into the battery case. I do. Next, the opening of the battery case is closed to obtain a non-aqueous electrolyte secondary battery.

In the above method, the addition rate of the positive electrode active material according to the present invention (addition rate = weight of active material according to the present invention × 1)
00% / (weight of active material according to the present invention + weight of active material in the form of primary particles)) was set to 30, 50, and 70%, respectively, and a non-aqueous electrolyte secondary battery was produced by the above method. . It was confirmed that the slurry could be prepared at any addition ratio.

FIG. 10 shows the relationship between the addition ratio of the active material and the ESR of the obtained battery, and FIG. 11 shows the relationship between the addition ratio of the active material and the high rate. It can be seen that the addition of the positive electrode active material according to the present invention results in a significant reduction in ESR. FIG. 12 shows Cole Cole of 18650 cells obtained when the addition rate of the active material according to the present invention is 30% and when only the primary particles are used as the active material without using the active material according to the present invention. Show the plot. It can be seen that the positive electrode plate according to the present invention has a low resistance. As described above, the active material according to the present invention has the ES
It turns out that it is effective in lowering R. FIG. 13 shows the output densities and energy densities of the batteries obtained when the addition rate of the active material according to the present invention was 30% and when only the primary particles were used as the active material without using the active material according to the present invention. The relationship is shown below. It can be seen that the battery using the active material according to the present invention exhibits excellent high-rate characteristics.
This is thought to be due to low ESR.

[0038]

As described above, the active material according to the present invention can exhibit a high power density and a high energy density for a secondary battery. Batteries using the active material according to the present invention, particularly non-aqueous electrolyte secondary batteries, are particularly useful for applications requiring high output, such as hybrid electric vehicles.

[Brief description of the drawings]

FIG. 1 is a perspective view schematically showing the structure of a lithium secondary battery.

FIG. 2 is a diagram showing P / E characteristics of a consumer lithium ion battery (18650 size).

FIG. 3 shows a non-aqueous electrolyte secondary battery (186) according to the present invention.
FIG. 10 is a diagram showing P / E characteristics of the P / E (50 size).

FIG. 4 is a diagram for explaining the height, width, and length of an active material according to the present invention.

FIG. 5 is an electron micrograph showing the state of bonding of primary particles in the active material according to the present invention.

FIGS. 6A and 6B are electron micrographs showing the surface of a positive electrode plate of a consumer lithium-ion battery.

FIG. 7 is an electron micrograph showing the surface of a positive electrode plate using the active material according to the present invention.

FIG. 8 is a view showing the result of measuring the particle size distribution of an active material obtained by the present invention with a laser diffraction particle size distribution meter.

FIG. 9 is an electron micrograph showing a flaky active material of an example according to the present invention.

FIG. 10 is a graph showing the relationship between the addition ratio of an active material according to the present invention and ESR for a 18650-size non-aqueous electrolyte secondary battery.

FIG. 11 is a graph showing the relationship between the addition rate of the active material according to the present invention and the high rate for a nonaqueous electrolyte secondary battery of 18650 size.

FIG. 12 shows a non-aqueous electrolyte secondary battery (18) according to the present invention.
650) shows a Cole-Cole plot.

FIG. 13 is a diagram comparing P / E characteristics of a consumer lithium ion battery and a non-aqueous electrolyte secondary battery according to the present invention.

[Explanation of symbols]

10 battery container, 11 positive electrode, 12 negative electrode, 13 separator.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Daisuke Kishimoto 1-1, Sanyocho, Daito-shi, Osaka Inside Sanyo Electronics Parts Products Co., Ltd. (72) Kazuo Terashi 1-1-1, Sanyocho, Daito-shi, Osaka (72) Inventor: Yutaka Takeya 1-1, Sanyocho, Daito-shi, Osaka F-term (reference) 5H003 AA02 BA01 BA04 BB05 BB15 BC01 BD02 BD03 5H014 AA01 AA02 BB01 EE10 HH01 HH06 5H029 AJ03 AK03 AL06 AM03 AM05 AM07 BJ02 BJ14 CJ02 CJ07 DJ16 HJ04 HJ05

Claims (8)

[Claims] 1. A particle of a porous sintered body to which particles of a metal oxide are joined, wherein a ratio of a width to a height is 2 or more, and a ratio of a length to a height is 2 or more. A positive electrode active material for a secondary battery, comprising: 2. The positive electrode active material for a secondary battery according to claim 1, wherein the positive electrode active material has a scale shape. 3. The positive electrode active material for a secondary battery according to claim 1, wherein the height is 40 μm or less. 4. The positive electrode active material for a secondary battery according to claim 1, wherein the positive electrode active material has a particle size of 5 μm to 600 μm. 5. The positive electrode active material for a secondary battery according to claim 1, wherein the metal oxide is a metal oxide containing lithium. 6. An active material according to any one of claims 1 to 5, and a conductive carbon.
A positive electrode active material composition for a non-aqueous electrolyte secondary battery. 7. A non-aqueous electrolyte secondary battery comprising the active material according to claim 1 in a positive electrode. 8. The method for producing a positive electrode active material for a secondary battery according to claim 1, wherein the material obtained by bonding the metal oxide powder is crushed to an appropriate size, and Obtaining particles having a width ratio of 2 or more and a length to height ratio of 2 or more;
And a step of firing the obtained particles.