A positive electrode active material includes powder of composite particles including a lithium transition metal composite oxide having a lamellar rock-salt structure and a spinel phase. The spinel phase includes an oxide including lithium and at least a first element X1 selected from the group consisting of magnesium, aluminum, titanium, manganese, yttrium, zirconium, molybdenum, and tungsten, and the lithium transition metal composite oxide includes nickel or cobalt and the first element X1.

The present invention relates to a positive electrode comprising a Mn composite oxide having a tetragonal structure represented by formula (1): Li.sub.a(M.sub.xMn.sub.2-x-yY.sub.y)(O.sub.4-wZ.sub.w)(wherein 1<a2.6, 0x1.2, 0y, x+y<2, 0w1; M is at least one selected from the group consisting of Co, Ni, Fe, Cr and Cu; Y is at least one selected from the group consisting of Li, B, Na, Mg, Al, Ti, Si, K and Ca; Z is at least one of F or Cl; and a composite oxide having a layered structure represented by formula (2): Li(Li.sub.xM.sub.1-x-yY.sub.y)O.sub.2 (wherein 0x<0.3, 0y<0.3; M is at least one selected from the group consisting of Co, Fe, Ni and Mn; Y is at least one selected from the group consisting of Mg, Al, Zr, Ti and Zn. According to the present invention, a lithium secondary battery having a high capacity and being excellent in cycle life can be provided.

A.sub.1xM.sub.2yO.sub.4, Formula 1

wherein, in Formula 1, A is at least one Group 1 element of the Periodic Table of the Elements, M is at least one metal element of Groups 2 to 16 of the Periodic Table of the Elements, with the proviso that M is neither Ti nor Mn, and Ox1, 0y1, and 01 are satisfied.

A positive electrode active material has a small difference in a crystal structure between the charged state and the discharged state. For example, the crystal structure and volume of the positive electrode active material, which has a layered rock-salt crystal structure in the discharged state and a pseudo-spinel crystal structure in the charged state at a high voltage of approximately 4.6 V, are less likely to be changed by charging and discharging as compared with those of a known positive electrode active material. In order to form the positive electrode active material having the pseudo-spinel crystal structure in the charged state, it is preferable that a halogen source such as a fluorine and a magnesium source be mixed with particles of a composite oxide containing lithium, a transition metal, and oxygen, which is synthesized in advance, and then the mixture be heated at an appropriate temperature for an appropriate time.

Provided is a positive electrode for a lithium ion battery, the electrode comprising a nano-crystalline layered-layered composite structure of a material having the general formula xLi.sub.2MO.sub.3(1x)LiMO.sub.2 in which 0<x<1, where M is one or more ion with an average oxidation state of three and with at least one ion being Mn or Ni, and where M is one or more ions with an average oxidation state of four. Another aspect provides a positive electrode for a lithium ion battery, the electrode comprising a nano-crystalline layered-spinel composite structure of a material having the general formula xLi.sub.2MnO.sub.3. (1x)LiMn.sub.2yM.sub.yO.sub.4 in which 0.5<x<1.0, 0y<1, and where M is one or more metal cations. Also provided is the positive electrode which comprises a nano-coating of inert oxide, inert phosphate or inert fluoride on the nano-crystalline composite structure. Additional aspects provide a lithium ion battery comprising a negative electrode, an electrolyte and the positive electrode, as well as methods of preparing the positive electrode composite structure and the nano-coating of inert oxide, inert phosphate or inert fluoride.

The present invention relates to a method of manufacturing a superparamagnetic nanocomposite and a superparamagnetic nanocomposite manufactured using the same, and more particularly to a method of manufacturing a superparamagnetic nanocomposite suitable for use in magnetic separation for the detection of a target biomaterial and a superparamagnetic nanocomposite manufactured using the same. The method of manufacturing the superparamagnetic nanocomposite according to the present invention has a higher yield and a high rate without complicated processing than a conventional method of manufacturing a magnetic nanoparticle for magnetic separation and is capable of mass production of the superparamagnetic nanocomposite having excellent properties with uniform size and particle size distribution, high aqueous solution dispersibility and high magnetization and being capable of maintaining superparamagnetism.

A lithium positive electrode active material intermediate comprising less than 80 wt % spinel phase and a net chemical composition of Li.sub.xNi.sub.yMn.sub.2-yO.sub.4- wherein 0.9x1.1; 0.4y0.5; and 0.1; where the lithium positive electrode active material intermediate has been heat treated in a reducing atmosphere at a temperature of from 300 C. to 1200 C. A process for the preparation of a lithium positive electrode active material with high tap density for a high voltage secondary battery where the cathode is fully or partially operated above 4.4 V vs. Li/Li+, comprising the steps of a) heating a precursor in a reducing atmosphere at a temperature of from 300 C. to 1200 C. to obtain a lithium positive electrode active material intermediate; b) heating the product of step a. in a non-reducing atmosphere at a temperature of from 300 C. to 1200 C.

A method for manufacturing a sputtering target with which an oxide semiconductor film with a small amount of defects can be formed is provided. Alternatively, an oxide semiconductor film with a small amount of defects is formed. A method for manufacturing a sputtering target is provided, which includes the steps of: forming a polycrystalline In-M-Zn oxide (M represents a metal chosen among aluminum, titanium, gallium, yttrium, zirconium, lanthanum, cesium, neodymium, and hafnium) powder by mixing, sintering, and grinding indium oxide, an oxide of the metal, and zinc oxide; forming a mixture by mixing the polycrystalline In-M-Zn oxide powder and a zinc oxide powder; forming a compact by compacting the mixture; and sintering the compact.

A mixed conductor represented by Formula 1:

A.sub.4+xM.sub.5-yM.sub.yO.sub.12-,Formula 1

wherein, in Formula 1, A is a monovalent cation, M is at least one of a divalent cation, a trivalent cation, or a tetravalent cation, M is at least one of a monovalent cation, a divalent cation, a trivalent cation, a tetravalent cation, a pentavalent cation, or a hexavalent cation, M and M are different from each other, and 0.3x<3, 0.01<y<2, and 01 are satisfied.

A ceramic material, a component, and a method for producing a component are disclosed. In an embodiment a ceramic material includes a structure based on a system selected from the group consisting of NiCoMnO, NiMnO and CoMnO, and at least one dopant selected from lanthanides, wherein the ceramic material has a negative temperature coefficient of an electrical resistance.