JP5720899B2 - Manganese nickel composite oxide particle powder and method for producing the same, method for producing positive electrode active material particle powder for non-aqueous electrolyte secondary battery, and non-aqueous electrolyte secondary battery - Google Patents

Description

  Disclosed are a manganese nickel composite oxide particle powder that has a high discharge voltage, a high discharge capacity, and excellent cycle characteristics, and that serves as a precursor of a positive electrode active material particle powder for a nonaqueous electrolyte secondary battery, and a method for producing the same.

  In recent years, electronic devices such as AV devices and personal computers are rapidly becoming portable and cordless, and there is an increasing demand for secondary batteries having a small size, light weight, and high energy density as power sources for driving these devices. In recent years, in consideration of the global environment, electric vehicles and hybrid vehicles have been developed and put into practical use, and the demand for a lithium ion secondary battery having excellent storage characteristics as a large-scale application is increasing. Under such circumstances, lithium ion secondary batteries having high energy having the advantage of high discharge voltage or large discharge capacity have attracted attention. Particularly, lithium ion secondary batteries are required to be charged and discharged quickly. Therefore, excellent rate characteristics are required for use in electric tools and electric vehicles.

Conventionally, as a positive electrode active material useful for a lithium ion secondary battery having a voltage of 4 V class, spinel type LiMn ₂ O ₄ , zigzag layered structure LiMnO ₂ , layered rock salt type structure LiCoO ₂ , LiNiO _2, etc. In general, lithium ion secondary batteries using LiNiO ₂ have attracted attention as batteries having a high discharge capacity.

However, since LiNiO ₂ has a low discharge voltage and is inferior in thermal stability, cycle characteristics, and rate characteristics during charging, further improvement in characteristics is required. There is also a problem that the structure is destroyed when high voltage charging is performed to obtain a high capacity.

In addition, LiMn ₂ O ₄ is excellent in rate characteristics and cycle characteristics, but has a low discharge voltage and discharge capacity, and is hardly a high-energy positive electrode active material.

Therefore, in recent years, a positive electrode active material having a high discharge voltage has attracted attention. Representative examples include LiNi _0.5 Mn _1.5 O ₄ , LiCoMnO ₄ , Li _1.2 Cr _0.4 Mn _0.4 O ₄ , Li _1.2 Cr _0.4 Ti _0.4 O ₄ , LiCoPO ₄ , LiFeMnO ₄ , LiNiVO _{4 and the} like are known.

Among them, LiNi _0.5 Mn _1.5 O ₄ has a high discharge voltage in which a discharge plateau region is present at 4.5 V or more, and is excellent in rate characteristics and cycle characteristics. Attention has been paid.

  From the viewpoint of energy density, a positive electrode active material having a higher capacity at a high voltage and satisfying cycle characteristics has been a continuous requirement from the past.

Conventionally, the _composition: LiNi _{0.5 Mn} 1.5 _{O 4} with respect to the positive electrode active material particles having, various improvements have been made (Patent Document 1 to 7 and Non-Patent Documents 1 and 2).

JP 2000-515672 A JP-A-9-147867 JP 2001-110421 A JP 2001-185145 A JP 2002-158007 A JP 2003-81637 A JP 2004-349109 A

48th Battery Discussion Meeting (2007) 2A16 J. et al. Electrochem. Society, 148 (7) A723-A729 (2001) Chem. Mater. 16,906-914 (2004)

  High energy positive electrode active materials for non-aqueous electrolyte secondary batteries with high discharge voltage, excellent discharge capacity, and good cycle characteristics are currently the most demanded, but still satisfy the necessary and sufficient requirements. Is not obtained.

  In other words, even with the techniques of Patent Documents 1 to 7 and Non-Patent Document 1, the operation is performed at a high voltage, the discharge capacity is excellent, and the long-term stability such as cycle characteristics is not sufficiently improved.

  Patent Document 1 reports that nickel-containing lithium manganate particles in which Ni is uniformly solid-solved are obtained by a sol-gel method in which manganese nitrate, nickel nitrate, and lithium nitrate are mixed with an ethanol solution using ethanol solvent and mixed with an ammonia solution. However, it is difficult to manufacture a large amount from an industrial viewpoint, and the discharge capacity is less than 100 mAh / g, which is not practical.

Patent Document 2 reports that a positive electrode active material that can be operated at a high voltage by a solid layer method by mixing electrolytic manganese dioxide, nickel nitrate, and lithium hydroxide and has excellent cycle characteristics is obtained. In the discharge curve, a plateau considered to be derived from Mn ³⁺ can be confirmed in the vicinity of 4 V, and the capacity due to the plateau exceeds 10 mAh / g. Therefore, it is unstable and not practical as a positive electrode material for high voltage. .

In Patent Document 3, a positive electrode active material is produced by producing a gel precursor by ball mill mixing lithium carbonate, MnO ₂ and nickel nitrate with an ethanol solvent, followed by firing. A positive electrode active material in which elements such as F, Cl, Si, and S have a concentration gradient toward the outside of the positive electrode active material particles by subjecting a compound such as F, Cl, Si, and S to surface treatment and firing. There is a report that the battery characteristics can be maintained by suppressing the reaction with the electrolyte in the battery at high voltage operation due to the effect of the element, but in this method, F, Cl, Si, and S are brought to the 16d site. Because of the substitution, the molar concentration of Mn and Ni at the site is relatively reduced, and as a result, the positive electrode active material particles themselves become brittle with respect to charge and discharge. Therefore, it is unstable and not practical as a positive electrode material for high voltage.

  In patent document 4, when co-precipitating with a manganese compound, a nickel compound, and an ammonium compound to obtain a spherical precursor whose primary particles are acicular, Ni and Mn are mixed with a Li compound and fired. Although it has been reported that the residual Ni (NiO) that can become an impurity layer can be reduced, it has been reported that a high discharge capacity and a high discharge capacity have been obtained, but only a discussion on the initial discharge capacity has led to a cycle. No mention is made of stability such as properties. In addition, the positive electrode active material according to the present invention may contain a large amount of impurities when the precursor is generated, and the impurities may cause instability in battery operation.

In patent document 5, after obtaining the spherical manganese nickel precursor which is a precursor by slowly dripping the solution which mixed ammonia as manganese sulfate, nickel sulfate, and a complexing agent in sodium hydroxide solution, Li compound Is subjected to main firing in a temperature range of 950 ° C. or higher, and then an annealing process is performed to obtain a high-voltage positive electrode active material. However, since the precursor has low crystallinity, it is mixed with a Li compound. In the subsequent main firing, it is necessary to perform firing at a temperature close to 1000 ° C., and as a result, Mn ³⁺ is generated from the shape of the charge / discharge curve for valence compensation due to oxygen deficiency. In addition, in this production method, a large amount of sodium and sulfur remain in the spherical particles, which may make the battery unstable.

  Patent Document 6 reports that after mixing lithium nitrate, manganese nitrate, and nickel nitrate, PVA was dropped and granulated, and then a high-capacity positive electrode material was obtained by firing at a maximum of 500 ° C. Since the firing temperature is low, it is difficult to increase the crystallinity, and long-term characteristics such as cycle characteristics may not be obtained due to the low crystallinity.

  In Patent Document 7, a mixture of manganese sulfate and nickel sulfate in a sodium hydroxide aqueous solution is pH-controlled and slowly dropped to produce spherical manganese nickel hydroxide with small primary particles without using a complexing material. In addition, by conducting a heat treatment of the hydroxide at 900 ° C., Ni was uniformly dissolved in the particles, and a nickel-manganese composite oxide having a high tap density was obtained, and a positive electrode active material reacted with a Li compound was reported. However, since the precursor according to the present invention does not use a complexing material, the shape of the aggregated secondary particles becomes distorted (from the SEM image), and a sufficient tap density can be obtained even if the precursor is heat-treated at a high temperature. Not.

  Non-Patent Document 1 describes that it has the crystal structure described in this specification, but does not describe a specific manufacturing method or its shape.

  Further, Non-Patent Document 2 discusses heat generation / endotherm associated with low-temperature phase transition due to oxygen deficiency of lithium manganate, but influence of oxygen deficiency of nickel-containing lithium manganate and substitution of Mn sites with Ni. There is no discussion of the behavior at low temperatures when such factors are added.

  Non-Patent Document 3 describes that the nickel-containing lithium manganate that gives good results is that the space group is Fd-3m, but when the manganese nickel composite composite oxide particle powder according to the present invention is used The nickel-containing lithium manganate particle powder is suitable for the material described in Non-Patent Document 3. Note that Non-Patent Document 3 does not consider at all the control of the characteristics of the manganese-nickel composite oxide particles used as the precursor of the nickel-containing lithium manganate.

  Therefore, in the present invention, a precursor suitable for the production of positive electrode active material particle powder comprising nickel-containing lithium manganate for a nonaqueous electrolyte secondary battery having a high discharge voltage, excellent charge / discharge capacity, and good cycle characteristics. Manganese nickel composite oxide particle powder, method for producing the same, method for producing positive electrode active material particle powder produced using the precursor, and non-aqueous electrolyte secondary comprising the positive electrode containing the positive electrode active material particle powder Provide batteries.

  The technical problem can be achieved by the present invention as follows.

  That is, the present invention is substantially a single phase in a composite oxide mainly composed of Mn and Ni, which is a cubic spinel having a space group of Fd-3m, and has an average primary particle size of 1.0 to 8. It is a manganese nickel composite oxide particle powder characterized by being in the range of 0 μm (Invention 1).

Further, the present invention provides the composite oxide particle powder according to the present invention 1, wherein the tap density is 1.8 g / ml or more, and the half-value width of the strongest peak by X-ray diffraction is in the range of 0.15 to 0.25. It is a manganese nickel composite oxide particle powder having a composition formula represented by the following chemical formula (1) (Invention 2).
Chemical formula (1)
(Mn _1-yz Ni _y M _z ) ₃ O ₄
0.2 ≦ y ≦ 0.3, 0 ≦ z ≦ 0.10
M: One or more than Mg, Al, Si, Ca, Ti, Co, Zn, Sb, Ba, W, Bi

  In the composite oxide particle powder according to the first or second aspect of the present invention, the sodium content is 100 to 2000 ppm, the sulfur content is 10 to 1000 ppm, and the total amount of impurities is 4000 ppm or less. Manganese nickel composite oxide particle powder (Invention 3).

  In addition, the present invention neutralizes the manganese salt aqueous solution with an excess amount of an alkaline aqueous solution with respect to the equivalent of manganese to obtain an aqueous suspension containing manganese hydroxide. By performing a primary reaction to obtain trimanganese tetroxide core particles by performing an oxidation reaction in a temperature range, adding a manganese raw material and a nickel raw material to the reaction solution after the primary reaction, and then performing a secondary reaction in which an oxidation reaction is performed, A manganese nickel composite compound having trimanganese tetraoxide particles as core particles is obtained, and then the manganese nickel composite compound having trimanganese tetroxide particles as core particles is fired in an oxidizing atmosphere at a temperature range of 900 to 1000 ° C. It is a manufacturing method of the manganese nickel complex oxide particle powder in any one of invention 1-3 (this invention 3).

  Further, the present invention provides the method for producing manganese nickel composite oxide particles according to the present invention 4, wherein the manganese concentration of the excess alkaline aqueous solution is 0.1 to 5.0 mol / L. (Invention 5).

  Further, the present invention provides the method for producing manganese nickel composite oxide particles according to the present invention 4 or 5, wherein the reaction solution after the primary reaction is switched to a non-oxidizing atmosphere and then the non-oxidizing atmosphere is maintained. It is a manufacturing method of the manganese nickel compound oxide particle powder which adds the manganese raw material and nickel raw material aqueous solution in a next reaction (this invention 6).

  The present invention also includes mixing the manganese nickel composite oxide particle powder according to any one of the first to third aspects of the present invention and a lithium compound, firing at 680 to 1050 ° C. in an oxidizing atmosphere, and subsequently continuing to 500 to 700 ° C. It is a manufacturing method of the positive electrode active material particle powder for non-aqueous electrolyte secondary batteries which has the cubic spinel structure baked by (Invention 7).

  Further, the present invention is a non-aqueous electrolyte secondary battery using the positive electrode active material particle powder obtained by the method for producing positive electrode active material particle powder according to the present invention 7 (Invention 8).

  When the manganese nickel composite oxide particle powder according to the present invention is a positive electrode active material particle powder obtained by synthesizing with a Li compound, the discharge voltage is high, the discharge capacity is large, and the cycle characteristics are good. Since a water electrolyte secondary battery is obtained, it is suitable as a precursor of positive electrode active material particle powder for non-aqueous electrolyte secondary batteries.

  Further, the positive electrode active material particle powder obtained by synthesizing with the Li compound using the manganese nickel composite oxide particle powder according to the present invention has good battery characteristics as described in Non-Patent Document 3. Since the nickel-containing lithium manganate particles having a space group of Fd-3m are obtained, the manganese-nickel composite oxide particles according to the present invention are suitable as a precursor.

2 is an X-ray diffraction pattern of the manganese nickel composite oxide particle powder obtained in Example 1. FIG. 2 is an X-ray diffraction pattern of nickel-containing manganese carbonate particle powder obtained in Comparative Example 1. FIG. 2 is a SEM image of manganese nickel composite oxide particle powder obtained in Example 1. FIG. 4 is a SEM image of nickel-containing manganese carbonate particle powder obtained in Comparative Example 1.

  The configuration of the present invention will be described in more detail as follows.

  The manganese nickel composite oxide particle powder according to the present invention is optimized as a precursor of the positive electrode active material particle powder for a non-aqueous electrolyte secondary battery.

  The manganese nickel composite oxide particle powder according to the present invention has a cubic spinel crystal structure having a space group of Fd-3m. When the other crystal structure is the main component, it becomes difficult for the positive electrode active material produced using the manganese nickel composite oxide particle powder to have a desired crystal structure.

As the manganese nickel composite oxide particle powder according to the present invention, (Mn _1-yz Ni _y M _z ) ₃ O ₄ (y range is 0.2 ≦ y ≦ 0.3, z range is 0 ≦ z ≦ 0.1), and as the M element, generally known additive elements such as B, Mg, Al, Si, Ca, Ti, Co, Zn, Y, Zr, Sb, Ba, W, Bi, etc. More preferable additive elements are Mg, Al, Si, Ti, Co, Zn, Y, Zr, Sb, and W. The content of the additive element is preferably 10 mol% or less with respect to the composite oxide.

  In the manganese nickel composite oxide particle powder according to the present invention, the Ni content is preferably 20 to 30 mol% with respect to the total amount of Me (total amount of Mn, Ni, and substitution element M). When the Ni content is less than 20 mol%, the positive electrode active material particle powder obtained using the precursor has a discharge plateau region of 4.5 V or more that is too low to obtain a high discharge capacity, and the structure is unstable. It becomes. When the Ni content exceeds 30 mol%, a large amount of impurity phase such as nickel oxide is generated in addition to the spinel structure in the positive electrode active material particle powder obtained using the precursor, and the discharge capacity is reduced. About Ni content, More preferably, it is 22-28 mol%, More preferably, it is 23-27 mol%.

  The manganese nickel composite oxide particle powder according to the present invention is attributed to the cubic manganese nickel composite oxide by X-ray diffraction. For that purpose, it is preferable that nickel is uniformly dispersed in trimanganese tetroxide which is a base material. The manganese nickel composite oxide particle powder according to the present invention preferably has a half width of the strongest peak ((311) plane) in X-ray diffraction in the range of 0.15 to 0.25. An impurity phase may be present when the half width of the peak is smaller than 0.15. Moreover, when the half width of the peak exceeds 0.25, nickel may not be uniformly dispersed in the manganese oxide particles. More preferably, the half width of the strongest peak is in the range of 0.15 to 0.22.

The average primary particle diameter of the manganese nickel composite oxide particle powder according to the present invention is in the range of 1.0 to 8.0 μm, and is preferably a secondary particle body in which primary particles are aggregated. When the average primary particle size is less than 1.0 μm, the metal content such as Ni and Mn tends to elute into the electrolyte when the battery is made, and the crystal structure may become unstable. On the other hand, when the average primary particle diameter exceeds 8.0 μm, the diffusion of Li into the precursor becomes insufficient in the mixed firing with the Li compound, resulting in an unstable structure.
A preferable average primary particle diameter is 1.5 to 7.5 μm, and more preferably 1.5 to 7.0 μm.

  Further, the tap density (500 times tapping) of the manganese nickel composite oxide particle powder according to the present invention is preferably 1.8 g / ml or more, more preferably 1.9 g / ml or more.

  The manganese nickel composite oxide particle powder according to the present invention preferably has a Na content of 100 to 2000 ppm. When the Na content is less than 100 ppm, the positive electrode active material particle powder obtained by using the oxide particle powder tends to have a weak force to retain the spinel structure. When the content exceeds 2000 ppm, the oxide particle powder In the positive electrode active material particle powder obtained by using lithium, lithium migration is hindered and the discharge capacity tends to decrease. The more preferable Na content in the oxide particle powder is 100 to 1800 ppm, and even more preferably 100 to 1700 ppm.

The manganese nickel composite oxide particle powder according to the present invention preferably has an S content of 10 to 1000 ppm. When the S content is less than 10 ppm, in the positive electrode active material particle powder obtained using the oxide particle powder, there is a tendency that S does not have an electrical effect on the movement of lithium, and when it exceeds 1000 ppm, Causes of micro short-circuits when a positive electrode active material particle powder obtained using the oxide particle powder is used as a battery to form FeSO ₄ and a compound locally and form FeSO _{4 and the} like locally. End up. A more preferable S content is 10 to 800 ppm, and even more preferably 10 to 700 ppm.

  The manganese nickel composite oxide particle powder according to the present invention has a total impurity content of 4000 ppm or less. When the total amount of impurities is greater than 4000 ppm, the composition of the final product of the positive electrode active material particle powder obtained using the oxide particle powder is deviated from the charged composition, resulting in a decrease in discharge capacity. The total amount of impurities is preferably 3500 ppm or less, and more preferably 3000 ppm or less.

  Next, a method for producing manganese nickel composite oxide particle powder according to the present invention will be described.

  That is, the manganese nickel composite oxide particle powder according to the present invention is an aqueous suspension containing manganese hydroxide by neutralizing an aqueous manganese salt solution with an excess of an aqueous alkaline solution relative to the equivalent of manganese. Then, a primary reaction is performed to obtain trimanganese tetroxide core particles by performing an oxidation reaction in a temperature range of 60 to 100 ° C., and a predetermined amount of manganese raw material and nickel raw material are added to the reaction solution after the primary reaction After performing a secondary reaction that performs an oxidation reaction by adding an aqueous solution in which an M element material is dissolved as necessary, it is washed and dried by an ordinary method to become an intermediate product of the manganese nickel composite oxide according to the present invention. A manganese nickel composite compound using trimanganese tetraoxide particles as a base material can be obtained, and the manganese nickel composite compound can be obtained by firing in an oxidizing atmosphere in a temperature range of 900 to 1100. That.

  The manganese compound and nickel compound used in the synthesis of the manganese nickel composite oxide particle powder are not particularly limited, and various oxides, hydroxides, chlorides, sulfates, nitrates, carbonates, acetates, etc. are used. In particular, it is preferable to use a sulfate.

  In the primary reaction in the wet process to obtain the intermediate product of manganese nickel composite oxide particles, the manganese salt aqueous solution is neutralized with an alkaline aqueous solution in excess of the equivalent of manganese and contains manganese hydroxide Then, an oxidation reaction is performed in a temperature range of 60 to 100 ° C. to obtain trimanganese tetroxide core particles. The method for synthesizing the core particles can be obtained according to the production method described in Japanese Patent No. 4305629.

After synthesizing the trimanganese tetroxide core particles by the primary reaction, after switching the reaction solution to the non-oxidizing atmosphere, the manganese raw material and the nickel raw material aqueous solution in the secondary reaction with the non-oxidizing atmosphere maintained. Add elemental raw material aqueous solution. The non-oxidizing atmosphere includes Ar, CO, CO ₂ , N ₂ , H _2, etc., but N ₂ is preferable.

  In addition, in addition to the trimanganese tetroxide core particles that are the base material in the reaction vessel, manganese, a manganese raw material aqueous solution and a nickel raw material aqueous solution, and if necessary, an M element raw material aqueous solution added to the reaction solution in a non-oxidizing atmosphere. Fine particles of nickel, M-element hydroxide or hydrated oxide are produced, and then the reaction solution is switched to an oxidizing atmosphere, whereby the hydroxide or hydrated oxide becomes an oxide and trimanganese tetraoxide. By performing some kind of reaction on the core particles, an intermediate product precipitate can be obtained without impairing the crystallinity of the core particles.

  Nickel raw materials include oxides, nitrates, sulfates, chlorides, carbonates, acetates, etc., but it is preferable to use sulfates.

  M element raw materials include Mg, Al, Si, Ca, Ti, Co, Zn, Sb, Ba, W, Bi oxides, nitrates, sulfates, chlorides, carbonates, acetates, etc. It is preferred to use a salt.

  Moreover, it is preferable to add an excessive amount of aqueous alkali solution in the primary reaction and the secondary reaction. The concentration is 0.1 to 5.0 mol / L. By reacting with an excessive amount of alkaline solution, the salt of the acidic substance is hardly taken in after the reaction, and as a result, the amount of impurities can be reduced. The concentration of the alkaline aqueous solution is preferably 0.5 to 4.0 mol / L.

  The alkaline aqueous solution is not particularly limited, and various basic materials can be used. For example, sodium carbonate, sodium hydroxide, lithium hydroxide, potassium carbonate, potassium hydroxide and the like are used, but it is preferable to use sodium hydroxide.

  The slurry containing the intermediate product obtained after the reaction is washed and dried according to a conventional method. In the cleaning step in the production method of the present invention, it is possible to wash away impurities such as excess sodium and sulfur adhering to the intermediate product without losing the nickel compound and M element compound deposited by the secondary reaction. .

  The obtained intermediate product can be baked in a temperature range of 900 to 1100 ° C. in an oxidizing atmosphere to obtain the manganese nickel composite oxide particle powder according to the present invention. When the firing temperature is lower than 900 ° C., not only Ni is not uniformly incorporated into the Mn oxide, but also a cubic nickel-nickel composite oxide having a spinel structure cannot be obtained. When the firing temperature exceeds 1100 ° C., Ni is deposited as an impurity such as NiO. The preferred firing temperature is 900 to 1000 ° C, the more preferred firing temperature is 900 to 980 ° C, and still more preferably 900 to 960 ° C.

  In the manganese nickel composite oxide particle powder, the particle size can be adjusted by pulverization after the firing step. In that case, it is necessary only to adjust the secondary particle diameter (D50) and to have an effect on the average primary particle diameter.

  Next, the positive electrode active material particle powder produced using the manganese nickel composite oxide particle powder in the present invention as a precursor will be described.

  The positive electrode active material particle powder using the manganese nickel composite oxide particle powder according to the present invention as a precursor is a nickel-containing lithium manganate particle powder having a spinel structure containing at least Li, Ni, and Mn, and is non-aqueous. It is suitable as a positive electrode active material particle powder of an electrolyte secondary battery. The nickel-containing positive electrode active material particle powder has high crystallinity and can be charged at a high voltage of 5 V without causing the structure to collapse, and can perform a high discharge capacity and a stable charge / discharge cycle.

  The positive electrode active material particle powder in the present invention is prepared by using the manganese nickel composite oxide particle powder according to the present invention as a precursor, mixed with a lithium compound at a predetermined molar ratio, and then fired at 680 ° C. to 1050 ° C. in an oxidizing atmosphere. Subsequently, it is obtained by firing at 500 to 700 ° C.

  The lithium compound used in the present invention is not particularly limited, and various lithium salts can be used. For example, lithium hydroxide monohydrate, lithium nitrate, lithium carbonate, lithium acetate, lithium bromide, chloride Examples thereof include lithium, lithium citrate, lithium fluoride, lithium iodide, lithium lactate, lithium oxalate, lithium phosphate, lithium pyruvate, lithium sulfate, and lithium oxide, with lithium carbonate being particularly preferable.

  The lithium compound used in the present invention preferably has an average particle size of 50 μm or less. More preferably, it is 30 μm or less. When the average particle diameter of the lithium compound exceeds 50 μm, mixing with the precursor becomes non-uniform and it becomes difficult to obtain composite oxide particles having good crystallinity.

  In addition, during the synthesis of the positive electrode active material particles in the present invention, together with the precursor and the lithium compound, Mg, Al, Si, Ca, Ti, Co, Zn, Sb, Ba, W, Bi nitrates, oxides, water An additive element may be introduced into the positive electrode active material particle powder by mixing an oxide, carbonate, or the like.

  The mixing treatment of the manganese nickel composite oxide particle powder and the lithium compound may be either dry or wet as long as it can be uniformly mixed.

  In the firing step of the mixture of the manganese nickel composite oxide particle powder and the lithium compound, firing at 680 ° C. to 1050 ° C. is preferably performed as the main firing in an oxidizing atmosphere. By this firing, the manganese-nickel composite compound and the lithium compound react to obtain nickel-containing lithium manganate in an oxygen deficient state. When the temperature is lower than 680 ° C., the reaction between Li, Ni, and Mn does not proceed sufficiently and is not sufficiently combined. When it exceeds 1050 ° C., the sintering proceeds too much, and Ni comes out of the lattice and precipitates as Ni oxide. The preferred firing temperature is 700 to 1000 ° C, and even more preferably 730 to 950 ° C. The firing time is preferably 2 to 50 hours.

  You may heat-process at 500 degreeC-700 degreeC in the same oxidizing atmosphere following this baking. This heat treatment makes it possible to easily obtain a nickel-containing positive electrode active material particle powder that compensates for oxygen deficiency and has a stable crystal structure.

Positive electrode active material particles used in the present invention have have spinel structure nickel-containing lithium manganate _{particles, Li 1 + x Mn 2-} y-z Ni y M z O 4 ( range of x is -0.05 ≦ x ≦ 0.10, the range of y is 0.4 ≦ y ≦ 0.6, and the range of z is 0 ≦ z ≦ 0.20). As the M element, Mg, Al, Si, Ca, Ti, Co, One or more of Zn, Sb, Ba, W, Bi, etc. may be substituted for Mn. Further, in the present invention, oxygen deficiency or oxygen excess may exist within a known range.

The average secondary particle diameter (D50) of the positive electrode active material particles in the present invention is preferably 4 to 30 μm, the specific surface area by the BET method is preferably 0.05 to 1.00 m ² / g, and the tap density (500 times) ) Is preferably 1.7 g / ml or more.

  The sodium content of the positive electrode active material particles in the present invention is preferably 30 to 2000 ppm, the sulfur content is preferably 10 to 600 ppm, and the total of impurities is preferably 5000 ppm or less.

  Next, the positive electrode using the positive electrode active material particle powder in the present invention will be described.

  When manufacturing the positive electrode containing the positive electrode active material particle powder in the present invention, a conductive agent and a binder are added and mixed according to a conventional method. As the conductive agent, acetylene black, carbon black, graphite and the like are preferable, and as the binder, polytetrafluoroethylene, polyvinylidene fluoride and the like are preferable.

  The secondary battery manufactured using the positive electrode containing the positive electrode active material particle powder in this invention is comprised from the said positive electrode, a negative electrode, and electrolyte.

  As the negative electrode active material, lithium metal, lithium / aluminum alloy, lithium / tin alloy, graphite, graphite, or the like can be used.

  In addition to the combination of ethylene carbonate and diethyl carbonate, an organic solvent containing at least one of carbonates such as propylene carbonate and dimethyl carbonate and ethers such as dimethoxyethane can be used as the solvent for the electrolytic solution.

  Further, as the electrolyte, in addition to lithium hexafluorophosphate, at least one lithium salt such as lithium perchlorate and lithium tetrafluoroborate can be dissolved in the above solvent and used.

  The non-aqueous electrolyte secondary battery manufactured using the positive electrode containing the positive electrode active material particle powder in the present invention has a capacity of 3.0 V or more of 130 mAh / g and a capacity of 4.5 V or more of 120 mAh according to an evaluation method described later. / G and the cycle retention ratio is 55% or more, preferably 60% or more. Moreover, the rate maintenance rate which took the ratio of 10C / 0.1C is 80% or more.

When the positive electrode active material particle powder in the present invention is used, since the crystallinity, which is a characteristic derived from the precursor, is high, the positive electrode active material is obtained by taking a method according to the method for producing the positive electrode active material particle powder in the present invention. The crystallinity in the spinel structure of the particle powder is also increased. As a result, the 16d site where Mn, Ni and M elements are coordinated is less expanded and contracted by charge and discharge, so that Li passes from the 8a site to the interface through the 16c site. It is thought that the ion diffusion resistance element which moves is reduced. As a result, Ni is removed from the structure and becomes a NiO component, and since oxygen deficiency is reduced, the capacity of 3.0 V to 4.5 V where a plateau due to Mn ³⁺ / Mn ⁴⁺ is seen is reduced, and cycle characteristics are improved. I think that.

<Action and discussion>
The manganese nickel composite oxide particle powder according to the present invention is characterized by a spinel structure, cubic crystals, and high crystallinity. In the present invention, a manganese raw material solution, a nickel raw material solution, and M are added to a reaction solution in which excess alkali content remains under nitrogen flow after generating highly crystalline trimanganese tetroxide core particles (seed particles) in advance. By adding the elemental raw material solution, hydroxide fine particles of the added metal can be generated. When the oxidation reaction is started with the atmosphere of the reaction solution being an oxidizing atmosphere, the hydroxide is a core particle. It is thought that it precipitates at the interface of trimanganese tetroxide particles. Also regarding this precipitation, fine particles of Mn, Ni, and M element hydroxides are precipitated as uniformly entangled oxides, so that no new particles are locally generated in the reaction solution, and they are core particles. A substitution element such as Ni can be disposed in the vicinity of the interface of the trimanganese tetroxide particles.

  Further, in the present invention, the average primary particle diameter after the secondary reaction can be controlled by variously changing the conditions of the primary reaction. As a result, the average primary particle diameter of the manganese nickel composite oxide particle powder according to the present invention can be controlled. The size can be designed freely. In addition, since the manganese nickel composite oxide particle powder according to the present invention is a wet and simple synthesis, it is possible to reduce impurities Na and S by controlling pH. In addition, impurities contained in the raw material and the like can be further washed away in the water washing step.

  Next, the intermediate product after the reaction is washed with water to wash out the impurities, and the intermediate product is baked at 900 to 1100 ° C., whereby nickel oxide and M element oxide are core particles. It can be uniformly dissolved in trimanganese tetroxide. In addition, as an effect due to the high firing temperature, it is considered that the surface properties of the primary particles can be smoothed, strong secondary particles can be formed, and the crystallinity of the particle powder can be increased. ing.

  The manganese nickel composite oxide particle powder according to the present invention is capable of uniformly solid-dissolving nickel oxide and optionally added M element oxide by firing, and obtaining a composite oxide having a cubic spinel structure. Can do.

  The manganese nickel composite oxide particle powder according to the present invention has high crystallinity, and after mixing with the Li compound, it can be fired at a temperature equal to or lower than the firing temperature when obtaining the manganese nickel composite oxide. When the positive electrode active material particle powder comprising nickel-containing lithium manganate having a strong spinel crystal skeleton can be obtained while maintaining the powder physical properties due to the high crystallinity of a certain manganese nickel composite oxide particle powder. Conceivable.

Further, in the production of the positive electrode active material particle powder made of the nickel-containing lithium manganate, the oxygen deficiency and the precipitation of the NiO composite oxide, which are increased by setting the firing temperature to around 900 ° C., can be suppressed, and therefore Mn ³⁺ Therefore, it is considered that the cycle characteristics can be improved.

  A typical embodiment of the present invention is as follows.

  The average primary particle diameter was observed using a scanning electron microscope SEM-EDX with an energy dispersive X-ray analyzer [manufactured by Hitachi High-Technologies Corporation], and the average value was read from the SEM image.

  The average secondary particle diameter (D50) is a volume-based average particle diameter measured by a wet laser method using a laser type particle size distribution measuring device Microtrac HRA [manufactured by Nikkiso Co., Ltd.].

  The BET specific surface area was measured using MONOSORB [manufactured by Yuasa Ionics Co., Ltd.] after drying and deaeration of the sample under nitrogen gas at 120 ° C. for 45 minutes.

  The composition and the amount of impurities were as follows: 0.2 g sample was heated and dissolved in 25 ml of a 20% hydrochloric acid solution, and after cooling, pure water was added to a 100 ml volumetric flask to prepare an adjustment solution. For measurement, ICAP [SPS-4000 Seiko Electronics Each element was quantified and determined using Kogyo Co., Ltd.].

  The packing density of the positive electrode active material particle powder was weighed 40 g, put into a 50 ml measuring cylinder, and the volume when tapped 500 times with a tap denser (manufactured by Seishin Enterprise Co., Ltd.) was read to calculate the packing density.

  The X-ray diffraction of the sample was measured using RAD-IIA manufactured by Rigaku Corporation.

  S content was measured using "HORIBA CARBON / SULFUR ANALYZER EMIA-320V (HORIBA Scientific)".

  About the positive electrode active material particle powder which concerns on this invention, battery evaluation was performed using CR2032-type coin cell.

For coin cells related to battery evaluation, 85% by weight of composite oxide as positive electrode active material particle powder, 5% by weight of acetylene black as a conductive material, 5% by weight of graphite, and polyvinylidene fluoride dissolved in N-methylpyrrolidone as a binder After mixing 5% by weight, it was applied to an Al metal foil and dried at 120 ° C. The sheet was punched out to 14 mmΦ, and then pressure-bonded at 1.5 t / cm ² was used as the positive electrode. A CR2032 type coin cell was manufactured using a solution in which EC and DMC in which 1 mol / L LiPF ₆ was dissolved was mixed at a volume ratio of 1: 2 with a negative electrode made of metallic lithium having a thickness of 500 μm punched to 16 mmΦ. .

  In addition, for the cycle maintenance rate evaluation, artificial graphite was used for the negative electrode, 94% by weight of the artificial graphite was mixed with 6% by weight of polyvinylidene fluoride dissolved in N-methylpyrrolidone as a binder, and then the Cu metal foil was mixed. The coin cell was produced in the same manner as when the counter electrode was a Li metal foil, except that it was applied, dried at 120 ° C., and punched to 16 mmΦ.

Charging / discharging characteristics were as follows: In a thermostatic chamber at 25 ° C., charging was performed at a current density of 0.1 C up to 5.0 V ( CC operation ), and then discharging was performed at a current density of 0.1 C up to 3.0 V. and it went (CC operation). In order to improve the reliability of the measurement, the charge capacity (2nd-CH) and the discharge capacity (2nd-DCH) of the second operation (second cycle) of this operation were measured as aging in the first cycle.

The rate maintenance rate was 25 ° C. in a thermostatic chamber. Charging was performed at a current density of 0.1 C up to 5.0 V ( CC operation ), and then discharging was performed at a current density of 0.1 C up to 3.0 V. ( CC operation ). In order to improve the reliability of the measurement, the charge capacity (2nd-CH) and the discharge capacity (2nd-DCH) of the second operation (second cycle) of this operation were measured as aging in the first cycle. At this time, the second discharge capacity is a. Next, charging was performed at a current density of 0.1 C up to 5.0 V ( CC operation ), and then discharging was performed at a current density of 10 C up to 3.0 V ( CC operation ). When the discharge capacity at this time is b, the rate maintenance rate is (b / a × 100 (%)).

Evaluation of cycle characteristics using artificial graphite as a counter electrode was performed using a CR2032-type coin cell. In the cycle characteristics test, 200 cycles of charge and discharge were performed at a current density of 1 C and from 3.0 V to 4.8 V ( CC operation ) in an environment of 25 ° C. At this time, assuming that the discharge capacity c of the first cycle and the discharge capacity d of the 200th cycle, the cycle retention rate was (d / c × 100 (%)).

Example 1
A sodium hydroxide aqueous solution was adjusted so that the excess alkali concentration after the reaction was 2.5 mol / L under nitrogen flow, and the manganese sulfate aqueous solution was adjusted so that the manganese concentration was 0.6 mol / L. An aqueous suspension containing manganese hydroxide particles was obtained by charging the total amount of oxide to 600 L and neutralizing the oxide. The resulting aqueous suspension containing manganese hydroxide particles was switched from nitrogen ventilation to air ventilation, and an oxidation reaction was performed at 90 ° C. (primary reaction).
After completion of the primary reaction, the system was switched to nitrogen aeration, and 117.3 L of a 0.3 mol / L manganese sulfate solution and 39.4 L of a 1.5 mol / L nickel sulfate solution were added to the reaction solution. An aqueous suspension containing manganese oxide and an additive metal compound (manganese hydroxide, nickel hydroxide, etc.) was obtained. The obtained reaction solution was switched from nitrogen aeration to air aeration, and an oxidation reaction was performed at 60 ° C. (secondary reaction). After completion of the secondary reaction, the resultant was washed with water and dried to obtain a manganese nickel composite compound (intermediate product) using Mn ₃ O ₄ particles having a spinel structure as a base material. The intermediate product was fired at 950 ° C. in the air for 20 hours to obtain manganese nickel composite oxide particle powder.

It was confirmed by X-ray diffraction that the obtained manganese nickel composite oxide particle powder was a cubic type (spinel structure) (FIG. 1). Its composition was (Mn _0.75 Ni _0.25 ) ₃ O ₄ . The average primary particle size is 2.6 μm, the tap density (500 times) is 2.12 g / ml, the half-width of the strongest peak in X-ray diffraction is 0.20 degrees, and the Na content is 252 ppm, The S content was 88 ppm and the total amount of impurities was 1589 ppm. An electron micrograph (SEM) of the obtained manganese nickel composite oxide particle powder is shown in FIG.

Example 2
A sodium hydroxide aqueous solution was adjusted so that the excess alkali concentration after the reaction was 2.5 mol / L under nitrogen flow, and the manganese sulfate aqueous solution was adjusted so that the manganese concentration was 0.6 mol / L. An aqueous suspension containing manganese hydroxide particles was obtained by charging the total amount of oxide to 600 L and neutralizing the oxide. The resulting aqueous suspension containing manganese hydroxide particles was switched from nitrogen ventilation to air ventilation, and an oxidation reaction was performed at 90 ° C. (primary reaction).

After the completion of the primary reaction, the system was switched to nitrogen aeration, and 0.37.3 mol / L manganese sulfate solution, 117.3 L, 1.5 mol / L nickel sulfate solution, 39.4 L, and 1.5 mol / L titanyl sulfate solution, 10 were added to the reaction solution. 0.0 L and 10.0 mol of a 1.5 mol / L magnesium sulfate solution are added, and the compound of manganese oxide and added metal produced in the primary reaction (manganese hydroxide, nickel hydroxide, magnesium hydroxide and hydroxide) An aqueous suspension containing titanium etc.) was obtained. The obtained reaction solution was switched from nitrogen aeration to air aeration, and an oxidation reaction was performed at 60 ° C. (secondary reaction). After completion of the secondary reaction, the resultant was washed with water and dried to obtain a manganese nickel composite compound (intermediate product) using Mn ₃ O ₄ particles having a spinel structure as a base material.

  The intermediate product was fired at 950 ° C. in the air for 20 hours to obtain manganese nickel composite oxide particle powder. It was confirmed by X-ray diffraction that the obtained manganese nickel composite oxide particle powder was a cubic type (spinel structure).

  Table 1 shows various characteristics of the obtained manganese nickel composite oxide particle powder.

Example 3
A sodium hydroxide aqueous solution was adjusted so that the excess alkali concentration after the reaction was 2.0 mol / L under nitrogen flow, and the manganese sulfate aqueous solution was adjusted so that the manganese concentration was 0.6 mol / L. An aqueous suspension containing manganese hydroxide particles was obtained by charging the total amount of oxide to 600 L and neutralizing the oxide. The resulting aqueous suspension containing manganese hydroxide particles was switched from nitrogen ventilation to air ventilation, and an oxidation reaction was performed at 90 ° C. (primary reaction).

  After the completion of the primary reaction, the system was switched to nitrogen aeration. In the same reaction solution, 117.3 L of a 0.3 mol / L manganese sulfate solution, 39.4 L of a 1.5 mol / L nickel sulfate solution, and a 1.5 mol / L titanyl sulfate solution 50 were added. By adding 2 L, an aqueous suspension of a compound of manganese oxide generated in the primary reaction and an added metal (such as manganese hydroxide, nickel hydroxide and titanium hydroxide) was obtained. The resulting solution was switched from nitrogen aeration to air aeration and an oxidation reaction was performed at 60 ° C. (secondary reaction).

After completion of the secondary reaction, the resultant was washed with water and dried to obtain a manganese nickel composite compound (intermediate product) using Mn ₃ O ₄ particles having a spinel structure as a base material.

  The intermediate product was fired at 950 ° C. in the air for 20 hours to obtain manganese nickel composite oxide particle powder. It was confirmed by X-ray diffraction that the obtained manganese nickel composite oxide particle powder was a cubic type (spinel structure).

  Table 1 shows various characteristics of the obtained manganese nickel composite oxide particle powder.

Examples 4 and 5
Manganese nickel composite oxide particle powders were produced by changing the production conditions based on Example 1.
Table 1 shows various characteristics of the obtained manganese nickel composite oxide particle powder.

Comparative Example 1
14 L of water was put into the sealed reaction tank, and kept at 50 ° C. while circulating nitrogen gas. Furthermore, 1.5 mol / L Ni, Mn mixed sulfate aqueous solution, 0.8 mol / L sodium carbonate aqueous solution, and 2 mol / L continuously with vigorous stirring so that pH = 8.2 (± 0.2). L Ammonia aqueous solution was added. During the reaction, only the filtrate was discharged out of the system by a concentrating device, and the solid content was retained in the reaction tank. After reacting for 40 hours, a slurry of the coprecipitation product was collected. The collected slurry was filtered and washed with pure water. Thereafter, it was dried at 105 ° C. overnight to obtain precursor particle powder. As a result of the X-ray diffraction measurement, the obtained precursor particle powder was mainly composed of carbonate (FIG. 2). An electron micrograph (SEM) of the obtained precursor particle powder is shown in FIG.

Comparative Example 2
In the same manner as in Example 1, a manganese nickel composite compound (intermediate product) was obtained, and the dried powder after drying was fired in the atmosphere at 880 ° C. for 20 hours to obtain manganese nickel composite oxide particle powder. As a result of X-ray diffraction, a peak of Mn ₂ O ₃ was observed in addition to the peak of the manganese nickel composite oxide having a spinel structure as the main structure.

  Table 1 shows various characteristics of the obtained manganese nickel composite oxide particle powder.

Comparative Example 3
14 L of water was put into the sealed reaction tank, and kept at 50 ° C. while circulating nitrogen gas. Furthermore, 1.5 mol / L Ni, Mn mixed sulfate aqueous solution, 0.8 mol / L sodium hydroxide aqueous solution and 2 mol / L are continuously added while vigorously stirring so that pH = 8.2 (± 0.2). L Ammonia aqueous solution was added. During the reaction, only the filtrate was discharged out of the system by a concentrating device, and the solid content was retained in the reaction tank. After reacting for 40 hours, a slurry of the coprecipitation product was collected. The collected slurry was filtered and washed with pure water. Thereafter, it was dried at 105 ° C. overnight to obtain precursor particle powder. As a result of the X-ray diffraction measurement, the obtained precursor particle powder was mainly composed of hydroxide (partially changed to oxide by drying).

  Various characteristics of the obtained manganese nickel compound are shown in Table 1.

Example 6
The manganese nickel composite oxide particles obtained in Example 1 and lithium carbonate were weighed so that Li: (Mn + Ni) = 0.50: 1.00, and dry-mixed with a ball mill for 1 hour to obtain a uniform mixture. Got. Thereafter, using an electric furnace, firing was performed at 750 ° C. for 15 hours under oxygen flow, followed by firing at 600 ° C. for 10 hours to obtain positive electrode active material particle powder.

The positive electrode active material particle powder was confirmed by X-ray diffraction (Rigaku RAD-IIA) to have a cubic spinel structure. The BET specific surface area was 0.43 m ² / g, D50 was 15.1 μm, and the tap density was 1.95 g / ml. The S content was 18 ppm, the Na content was 95 ppm, and the total amount of impurities was 513 ppm.

  In addition, the coin-type battery produced using the positive electrode active material particle powder has a discharge capacity of up to 3.0 V of 140 mAh / g, a discharge capacity of up to 4.5 V is 132 mAh / g, and the rate maintenance rate is At 88%, the cycle retention was 63%.

Examples 7 and 8
Positive electrode active material particle powder was obtained in the same manner as in Example 6 except that the type of manganese nickel composite oxide particle powder, the mixing ratio with lithium carbonate, and the firing temperature were variously changed. As a result of X-ray diffraction, the obtained positive electrode active material particle powder was confirmed to have a spinel structure that is a cubic crystal.

  Table 2 shows the analysis results of the obtained positive electrode active material particle powder.

Example 9
The mixture of the manganese nickel composite oxide particle powder obtained in Example 4 and lithium carbonate was fired at 900 ° C. for 15 hours under air flow, and then fired at 600 ° C. for 10 hours to obtain positive electrode active material particle powder. It was. As a result of X-ray diffraction, the obtained positive electrode active material particle powder was confirmed to have a spinel structure that is a cubic crystal.

  Table 2 shows the analysis results of the obtained positive electrode active material particle powder.

Example 10
The mixture of the manganese nickel composite oxide particle powder and lithium carbonate obtained in Example 5 was fired at 750 ° C. for 15 hours under air flow, and then fired at 600 ° C. for 10 hours to obtain positive electrode active material particle powder. It was. As a result of X-ray diffraction, the obtained positive electrode active material particle powder was confirmed to have a spinel structure that is a cubic crystal.

  Table 2 shows the analysis results of the obtained positive electrode active material particle powder.

Comparative Example 4
The precursor particle powder and lithium hydroxide obtained in Comparative Example 1 were weighed, weighed so that Li: Me = 0.48: 1.00, and mixed well. The mixture was baked in an electric furnace at 1000 ° C. for 8 hours in the atmosphere, and then baked at 600 ° C. for 6 hours to obtain positive electrode active material particle powder.

  Table 2 shows the analysis results of the obtained positive electrode active material particle powder.

Comparative Example 5
The precursor particle powder and lithium hydroxide obtained in Comparative Example 1 were weighed and weighed so that Li: Me = 0.50: 1.00 and mixed well. The mixture was baked in an electric furnace at 1000 ° C. for 8 hours in the atmosphere, and then baked at 600 ° C. for 6 hours to obtain positive electrode active material particle powder.

  Table 2 shows the analysis results of the obtained positive electrode active material particle powder.

Comparative Example 6
The precursor particle powder and lithium hydroxide obtained in Comparative Example 1 were weighed and weighed so that Li: Me = 0.51: 1.00 and mixed well. The mixture was baked in an electric furnace at 1000 ° C. for 8 hours in the atmosphere, and then baked at 600 ° C. for 6 hours to obtain positive electrode active material particle powder.

  Table 2 shows the analysis results of the obtained positive electrode active material particle powder.

Comparative Example 7
The composite oxide obtained in Comparative Example 2 was used as a precursor and mixed with a Li compound and fired in the same manner as in Example 1 to obtain positive electrode active material particle powder. The obtained positive electrode active material particle powder confirmed the peak of nickel-containing lithium manganate, nickel oxide, and Mn ₂ O ₃ -derived lithium manganate particles by X-ray diffraction. This is presumably because the amount of Ni was relatively increased due to the decrease in the amount of Mn in the manganese nickel composite oxide due to the occurrence of heterogeneous phases.

  Table 2 shows the analysis results of the obtained positive electrode active material particle powder.

Comparative Example 8
Except that the composite oxide obtained in Comparative Example 3 was used as a precursor, it was mixed with a Li compound and fired in the same manner as in Example 7 to obtain a positive electrode active material particle powder. The obtained positive electrode active material particle powder confirmed the peak of nickel-containing lithium manganate, nickel oxide, and Mn ₂ O ₃ -derived lithium manganate particles by X-ray diffraction. This is presumably because the amount of Ni was relatively increased due to the decrease in the amount of Mn in the manganese nickel composite oxide due to the occurrence of heterogeneous phases.

  Table 2 shows the analysis results of the obtained positive electrode active material particle powder.

  From the above results, the positive electrode active material particle powder made of nickel-containing lithium manganate obtained when the manganese nickel composite oxide particle powder according to the present invention is used is excellent in non-aqueous electrolyte secondary batteries having a large charge / discharge capacity. It was confirmed to be effective as a positive electrode active material.

  The manganese nickel composite oxide particle powder according to the present invention has a high discharge capacity and excellent cycle characteristics when made into a positive electrode active material particle powder comprising nickel-containing lithium manganate synthesized using the oxide as a precursor. Since a positive electrode active material for a non-aqueous electrolyte secondary battery is obtained, it is suitable as a precursor of the positive electrode active material.

Claims (7)

In cubic Mn and Ni composite oxide of the main component is a spinel having a space group of fd-3m, a substantially single phase, an average primary particle diameter of Ri range der of 1.0~8.0μm The tap density is 1.8 g / ml or more, the half-value width of the strongest peak by X-ray diffraction is in the range of 0.15 to 0.25, and the composition formula is represented by the following chemical formula (1) Manganese nickel composite oxide particle powder.
Chemical formula (1)
(Mn _1-yz Ni _y M _z ) ₃ O ₄
0.2 ≦ y ≦ 0.3, 0 ≦ z ≦ 0.10
M: One or more than Mg, Al, Si, Ca, Ti, Co, Zn, Sb, Ba, W, Bi In the composite oxide particles according to claim 1 Symbol placement, a sodium content is 100 to 2000 ppm, a sulfur content of 10-1000 ppm, manganese nickel composite oxide particles sum of impurities is less than 4000 ppm. An aqueous manganese salt solution is neutralized with an aqueous alkaline solution in excess of the equivalent of manganese to form an aqueous suspension containing manganese hydroxide, and then subjected to an oxidation reaction at a temperature range of 60 to 100 ° C. To obtain a trimanganese tetroxide core particle, and after adding a manganese raw material and a nickel raw material to the reaction solution after the primary reaction, the trimanganese tetroxide particles are obtained by a secondary reaction in which an oxidation reaction is performed. the resulting manganese-nickel composite compounds with core particles and then, according to the trimanganese tetraoxide particles in claim 1 or 2, fired at a temperature range of 900 to 1100 ° C. the manganese-nickel composite compound as the core particles in an oxidizing atmosphere Manufacturing method for manganese nickel composite oxide particles. 4. The method for producing manganese nickel composite oxide particle powder according to claim 3, wherein the alkali concentration of an excessive amount of the alkaline aqueous solution is 0.1 to 5.0 mol / L. In the manufacturing method of the manganese nickel complex oxide particle powder of Claim 3 or 4 , after switching the reaction solution after primary reaction to non-oxidizing atmosphere, in the state which hold | maintained this non-oxidizing atmosphere, the manganese raw material in secondary reaction, The manufacturing method of the manganese nickel compound oxide particle powder which adds nickel raw material aqueous solution. The manganese nickel composite oxide particle powder according to claim 1 or 2 and a lithium compound are mixed, fired at 680 to 1050 ° C. in an oxidizing atmosphere, and subsequently fired at 500 to 700 ° C. The manufacturing method of the positive electrode active material particle powder for nonaqueous electrolyte secondary batteries. The nonaqueous electrolyte secondary battery using the positive electrode active material particle powder obtained by the manufacturing method of the positive electrode active material particle powder of Claim 6 .