An iron-based oxide magnetic particle powder has a narrow particle size distribution a small content of fine particles that do not contribute to magnetic recording characteristics, and a narrow coercive force distribution, to enhance magnetic recording medium density. Neutralizing an aqueous solution containing a trivalent iron ion and an ion of the metal substituting a part of the Fe sites by adding an alkali to make pH of 1.5 or more and 2.5 or less, adding a hydroxycarboxylic acid, and further neutralizing by adding an alkali to make pH of 8.0 or more and 9.0 or less are performed at 5 C. or more and 25 C. or less. A formed iron oxyhydroxide precipitate containing the substituting metal element is rinsed with water, then coated with silicon oxide, and then heated thereby providing e-type iron-based oxide magnetic particle powder. The rinsed precipitate may be subjected to a hydrothermal treatment.

Provided is a precursor of a positive electrode active material containing, in a reduced amount, impurities which do not contribute to a charge/discharge reaction but rather corrode a firing furnace and peripheral equipment and thus having excellent battery characteristics and safety, and production method thereof. A method for producing a precursor of a positive electrode active material for nonaqueous electrolyte secondary batteries having a hollow structure or porous structure includes obtaining the precursor by washing nickel-manganese composite hydroxide particles having a particular composition ratio and a pore structure in which pores are present within the particles with an aqueous carbonate solution having a carbonate concentration of 0.1 mol/L or more.

Process for synthesizing a material, the process including the steps consisting in: a) providing a plurality of powders including: at least one powder including lithium, at least one powder including, for more than 95.0% of its mass, a transition metal chosen from titanium, cobalt, manganese, nickel, niobium, tin, iron and mixtures thereof, and at least one powder including, for more than 95.0% of its mass, a chalcogen element chosen from sulfur, selenium, tellurium and mixtures thereof, b) preparing a particulate mixture by mixing all the powders of the plurality or by mixing one of the powders of the plurality with a milled material obtained by milling a particulate assembly formed by mixing at least two of the other powders of the plurality, and milling the particulate mixture to form the material.

A positive electrode active material contains a lithium composite oxide containing fluorine and oxygen. The lithium composite oxide satisfies 1<Zs/Za<8, where Zs represents a first ratio of a molar quantity of fluorine to a total molar quantity of fluorine and oxygen in XPS of the lithium composite oxide, and Za represents a second ratio of a molar quantity of fluorine to a total molar quantity of fluorine and oxygen in an average composition of the lithium composite oxide. An XRD pattern of the lithium composite oxide includes a first maximum peak within a first range of 18 to 20 at a diffraction angle 2 and a second maximum peak within a second range of 43 to 46 at the diffraction angle 2. The ratio I.sub.(18-20)/I.sub.(43-46) of a first integrated intensity I.sub.(18-20) of the first maximum peak to a second integrated intensity I.sub.(43-46) of the second maximum peak satisfies 0.05I.sub.(18-20)/I.sub.(43-46)0.90.

Mixed-metal oxides and lithiated mixed-metal oxides are disclosed that involve compounds according to, respectively, Ni.sub.xMn.sub.yCo.sub.zMe.sub.O.sub. and Li.sub.1+Ni.sub.xMn.sub.yCo.sub.zMe.sub.O.sub.. In these compounds, Me is selected from B, Na, Mg, Al, Si, K, Ca, Sc, Ti, V, Cr, Fe, Cu, Zn, Ga, Ge, Zr, Nb, Mo, Ru, Ag, In, and combinations thereof; 0x1; 0y1; 0z<1; x+y+z>0; 00.5; and x+y+>0. For the mixed-metal oxides, 15. For the lithiated mixed-metal oxides, 0.11.0 and 1.93. The mixed-metal oxides and the lithiated mixed-metal oxides include particles having an average density greater than or equal to 90% of an ideal crystalline density.

A hydrothermal synthesis for LiFePO.sub.4 is provided. First, each raw material solution is prepared using a degassed water in advance, second, those solution are mixed by dripping in a fixed order, and then those materials are reacted in a hydrothermal synthesis, so that LiFePO.sub.4 is obtained in a predesigned form.

Ferrite films, antennas including ferrite films, and methods of making thereof are provided. The methods can include tape casting of a slurry to produce a green film, wherein the slurry includes a ferrite powder, a dispersant, and a binder in a suitable solvent; and densifying the green film to produce the ferrite film having a thickness of 50 m to 5 mm. The methods can be used to make large area films, for example the films can have a lateral area of about 1000 cm.sup.2 to 3000 cm.sup.2. VHF/UHF antennas are including the ferrite films are also provided.

The present invention related to an electrochemical cell comprising an anode of a Group IA metal and a cathode of a composite material prepared from an aqueous mixture of iron sulfate, cobalt sulfate and sulfur. The cathode material of the present invention provides an increased rate pulse performance compared to iron disulfide cathode material. This makes the cathode material of the present invention particularly useful for implantable medical applications.

Thermochemical storage materials having the general formula A.sub.xA.sub.1-xB.sub.yB.sub.1-yO.sub.3-, where A=La, Sr, K, Ca, Ba, Y and B=Mn, Fe, Co, Ti, Ni, Cu, Zr, Al, Y, Cr, V, Nb, Mo, are disclosed. These materials have improved thermal storage energy density and reaction kinetics compared to previous materials. Concentrating solar power thermochemical systems and methods capable of storing heat energy by using these thermochemical storage materials are also disclosed.

A positive-electrode active material contains a lithium composite oxide containing at least one selected from the group consisting of F, Cl, N, and S. The crystal structure of the lithium composite oxide belongs to a space group C2/m. An XRD pattern of the lithium composite oxide comprises a first peak within the first range of 44 degrees to 46 degrees of a diffraction angle 2 and a second peak within the second range of 18 degrees to 20 degrees of the diffraction angle 2. The ratio of the second integrated intensity of the second peak to the first integrated intensity of the first peak is within a range of 0.05 to 0.90.