Provided are nickel manganese composite hydroxide particles having a small and uniform particle size and having a double structure which enables to obtain a cathode active material having a hollow structure, and a manufacturing method thereof. When obtaining the nickel manganese composite hydroxide by a reaction crystallization, using an aqueous solution for nucleation, which includes at least a metallic compound that contains nickel, a metallic compound that contains manganese and an ammonium ion donor and controlling the pH value that is measured at a standard solution temperature of 25 C. is 10.5 to 12.0, nucleation is performed in an oxidizing atmosphere in which the oxygen concentration is greater than 1% by volume, and then nuclei are grown by switching the atmosphere from the oxidizing atmosphere to a mixed atmosphere of oxygen and inert gas in which the oxygen concentration is 1% by volume or less.

To provide a cathode active material having excellent cycle characteristics and a small decrease in the discharge voltage, and a process for its production. A process for producing a cathode active material, which comprises a step of mixing at least one sulfate (A) selected from the group consisting of a sulfate of Ni, a sulfate of Co and a sulfate of Mn with at least one carbonate (B) selected from the group consisting of sodium carbonate and potassium carbonate in an aqueous solution state to obtain a coprecipitated compound, a step of mixing the coprecipitated compound with an aqueous phosphate solution, a step of volatilizing a water content from the mixture of the coprecipitated compound and the aqueous phosphate solution to obtain a precursor compound, and a step of mixing the precursor compound with lithium carbonate and firing the mixture at from 500 to 1000 C.; and a cathode active material obtainable by the production process, which comprises Li, at least one transition metal element (X) selected from the group consisting of Ni, Co and Mn, and P, wherein the average coefficient of variation (CV value) of the calculated peak intensity ratio (Ip/Ix) of P to the transition metal element (X) is from 0 to 20% as determined by a method for measuring coefficient of variation.

A method of preparing a positive electrode active material precursor includes: providing a transition metal-containing solution including nickel, cobalt, and manganese; and introducing the transition metal-containing solution into a reactor, adding a basic aqueous solution and an ammonium cation-containing complex-forming agent, and performing a co-precipitation reaction to prepare a transition metal hydroxide in the form of a secondary particle formed by agglomerating primary particles. The co-precipitation reaction is performed under conditions satisfying Expression 1 described in the specification, and a positive electrode active material precursor whose crystalline grain has a controlled aspect ratio. A positive electrode active material prepared using the positive electrode active material precursor, a positive electrode for a lithium secondary battery, which includes the positive electrode active material, and a lithium secondary battery are also provided.

A positive electrode includes a first positive electrode material and a second material. The first positive electrode material includes Li.sub.1+xCo.sub.1?yM.sup.1.sub.yO.sub.2?-tA.sub.t, in which M.sup.1 includes Ni, Mn, Al, Mg, Ti, Zr, La, Y, Fe, Cr, V, Zn, Ru, Rh, Ga, Pd, Pt, Mo, W, Sb, Nb, Se, Te, and/or Ce; A includes S, N, F, Cl, and/or Br; ?0.1?x?0.2, 0?y?0.2, and 0?t?0.2. The second material includes Li.sub.1+rNi.sub.1?p?qM.sup.2.sub.pM.sup.3.sub.qO.sub.2?sD.sub.s and a phase B belonging to an F-3m1 space group. M.sup.2 and M.sup.3 independently include Co, Mn, Fe, Ti, Al, V, Cr, Nb, Zr, La, and/or Y. M.sup.2 and M.sup.3 are different elements. D includes S, N, F, Cl, and/or Br; 0<r?1, 0<p<1, 0<q<1, 0<p+q?0.5, and 0?s<0.2.

A hybrid particle having a core of a hybrid composite comprising at least two elements selected from the group consisting of sulfur, selenium and tellurium and a coating of at least one self-assembling polymeric layer encapsulating the core is provided. A method for preparing the hybrid particle includes mixing an aqueous solution of a polymer with an aqueous solution of a soluble precursor of at least two elements selected from the group consisting of sulfur, selenium and tellurium to form a mixture and adding an acid to the mixture to obtain the hybrid particle. A cathode having an active material of the hybrid particles and a battery containing the cathode are also provided.

Provided is a positive electrode active material for nonaqueous electrolyte secondary batteries that suppresses the gelling of a positive electrode mixture material paste and has high weather resistance, a production method thereof, and the like. A method for producing a positive electrode active material for nonaqueous electrolyte secondary batteries includes cleaning a powder famed of a lithium-nickel composite oxide represented by a general formula Li.sub.zNi.sub.1-x-yCo.sub.xM.sub.yO.sub.2 where 0x0.35; 0y0.10; 0.95z1.10; and M is at least one element selected from Mn, V, Mg, Mo, Nb, Ti, and Al with an aqueous solution containing one or more lithium salts selected from water-soluble lithium salts other than lithium hydroxide and drying the cleaned powder.

An oxide all-solid-state battery excellent in lithium ion conductivity and joint strength between an anode active material layer and solid electrolyte layer thereof. In the oxide all-solid-state battery, the solid electrolyte layer is a layer mainly containing a garnet-type oxide solid electrolyte sintered body represented by the following formula (1): (Li.sub.x-3y-z, E.sub.y, H.sub.z)L.sub.M.sub.O.sub.; a solid electrolyte interface layer is disposed between the anode active material layer and the solid electrolyte layer; the solid electrolyte interface layer contains at least a Si element and an O element; and a laminate containing at least the anode active material layer, the solid electrolyte interface layer and the solid electrolyte layer has peaks at positions where 2=32.30.5, 37.60.5, 43.80.5, and 57.70.5 in a XRD spectrum obtained by XRD measurement using CuK irradiation.

A graphene-enhanced transition metal fluoride or chloride hybrid particulate for use as a lithium battery cathode active material, wherein the particulate is formed of a single or a plurality of graphene sheets and a plurality of fine transition metal fluoride or chloride particles with a size smaller than 10 m (preferably sub-micron or nano-scaled), and the graphene sheets and the particles are mutually bonded or agglomerated into an individual discrete particulate with at least a graphene sheet embracing the transition metal fluoride or chloride particles, and wherein the particulate has an electrical conductivity no less than 10.sup.4 S/cm and the graphene is in an amount of from 0.01% to 30% by weight based on the total weight of graphene and the transition metal fluoride or chloride combined.

A production method of a negative electrode active material for non-aqueous electrolyte secondary batteries containing a silicon compound (SiO.sub.x: 0.51.6) that contains Li, includes: making a silicon compound into which the lithium has been inserted contact with a solution B containing a polycyclic aromatic compound or a derivative thereof or both thereof (here, the solution B contains one or more kinds selected from an ether-based solvent, a ketone-based solvent, an ester-based solvent, an alcohol-based solvent, and an amine-based solvent as the solvent); and making the silicon compound contact with a solution C (here, the solution C contains one or more kinds selected from an alcohol-based solvent, a carboxylic acid-based solvent, and water as the solvent). Thereby, a production method of a negative electrode active material for non-aqueous electrolyte secondary batteries is capable of increasing a battery capacity and improving the cycle characteristics.

Provided are nickel manganese composite hydroxide particles having a small and uniform particle size and having a double structure which enables to obtain a cathode active material having a hollow structure, and a manufacturing method thereof. When obtaining the nickel manganese composite hydroxide by a reaction crystallization, using an aqueous solution for nucleation, which includes at least a metallic compound that contains nickel, a metallic compound that contains manganese and an ammonium ion donor and controlling the pH value that is measured at a standard solution temperature of 25 C. is 10.5 to 12.0, nucleation is performed in an oxidizing atmosphere in which the oxygen concentration is greater than 1% by volume, and then nuclei are grown by switching the atmosphere from the oxidizing atmosphere to a mixed atmosphere of oxygen and inert gas in which the oxygen concentration is 1% by volume or less.