Abstract: A cathode electroactive material for use in lithium ion secondary cells, process for producing the material, and lithium ion secondary cells using the cathode electroactive material, wherein the electroactive material predominantly comprises an Li—Mn composite oxide particles with the spinel structure and particles of the electroactive material have an average porosity of 15% or less, the porosity being calculated by employing the following equation:

Abstract: A cathode electroactive material for use in lithium ion secondary cells, process for producing the material, and lithium ion secondary cells using the cathode electroactive material, wherein the electroactive material predominantly comprises an Li—Mn composite oxide particles with the spinel structure and particles of the electroactive material have an average porosity of 15% or less, the porosity being calculated by employing the following equation: Porosity (%)=(A/B)×100  (1) (wherein A represents a total cross-section area of pores included in a cross-section of one secondary particle, and B represents the cross-section area of one secondary particle), a tapping density of 1.9 g/ml or more, a size of crystallites of 400 Å-960 Å, a lattice constant of 8.240 Å or less.

Abstract: The present invention provides a cathode electroactive material comprising a composite oxide comprising &bgr;-MnO2 and a spinel oxide predominantly comprising lithium, manganese, and oxygen. The present invention provides a process for producing said material, which process comprises acid treatment of a composite oxide comprising a spinel oxide predominantly comprising lithium, manganese, and oxygen, and heat treatment of the resultant composite oxide at a temperature of about 200° C. or higher and lower than about 400° C. The thus-produced oxide is employed as a cathode electroactive material in a non-aqueous secondary cell.

Abstract: A cathode electroactive material for use in lithium ion secondary cells, process for producing the material, and lithium ion secondary cells using the cathode electroactive material, wherein the electroactive material predominantly comprises an Li—Mn composite oxide particles with the spinel structure and particles of the electroactive material have an average porosity of 15% or less, the porosity being calculated by employing the following equation:

Abstract: The present invention provides a barium titanate having a small particle size, containing small amounts of unwanted impurities, and exhibiting excellent electric characteristics, which can be employed for forming a dielectric ceramic thin film required for a small-sized capacitor which enables production of a small-sized electronic apparatus; and a process for producing the barium titanate. When a titanium oxide sol is reacted with a barium compound in an alkaline solution containing a basic compound, the basic compound is removed in the form of gas after completion of reaction, and the resultant reaction mixture is fired, a barium titanate having a large BET specific surface area and a high tetragonality content is produced.

Abstract: A cathode electroactive material is disclosed, comprising a compound oxide having a spinel structure. The compound oxide comprises lithium, manganese and oxygen and has an atomic ratio of lithium to manganese of Li/Mn=0.48 to 0.55, a true density of 4.05 g/cm3 or more and a lattice constant of 8.240 Å or less. The compound oxide is obtained by mixing a lithium compound with manganese carbonate having a specific surface area of 10 m2/g or more, then reacting the mixture at a temperature of from 350 to 680° C. for at least one hour, and heat-treating the resulting spinel structure compound oxide at a temperature of from 730 to 900° C. Also disclosed is a nonaqueous secondary battery comprising the cathode electroactive material.

Abstract: A cathode electroactive material is disclosed, comprising a compound oxide having a spinel structure. The compound oxide comprises lithium, manganese and oxygen and has an atomic ratio of lithium to manganese of Li/Mn=0.48 to 0.55, a true density of 4.05 g/cm3 or more and a lattice constant of 8.240 Å or less. The compound oxide is obtained by mixing a lithium compound with manganese carbonate having a specific surface area of 10 m2/g or more, then reacting the mixture at a temperature of from 350 to 680° C. for at least one hour, and heat-treating the resulting spinel structure compound oxide at a temperature of from 730 to 900° C. Also disclosed is a nonaqueous secondary battery comprising the cathode electroactive material.

Abstract: The present invention provides a cathode electroactive material comprising a composite oxide comprising &bgr;-MnO2 and a spinel oxide predominantly comprising lithium, manganese, and oxygen.