A negative electrode active material for an electricity storage device of the present invention includes TiO.sub.2, Na.sub.2O, and a network-forming oxide.

A positive electrode active material for a lithium ion secondary battery has a rock salt type structure represented by General Formula:

Li.sub.xTi.sub.2x-1Mn.sub.2-3xO (0.50<x<0.67)(1)

and has an average particle size of 0.5 m or less.

Provided is an alkali-metal titanate in which the content and adhesivity of the fibrous potassium titanate is significantly reduced. The alkali-metal titanate includes 0.5 mol to 2.2 mol of potassium oxide in terms of potassium atoms, 0.05 mol to 1.4 mol of sodium oxide in terms of sodium atoms, and 0 mol to 1.4 mol of lithium oxide in terms of lithium atoms relative to 1 mol of alkali-metal hexatitanate, in which a total content of potassium oxide in terms of potassium atoms, sodium oxide in terms of sodium atoms, and lithium oxide in terms of lithium atoms relative to 1 mol of alkali-metal hexatitanate is 1.8 mol to 2.3 mol; and the alkali-metal titanate has a single phase conversion ratio of 85% to 100%, a fiber ratio of 0% by volume to 10% by volume, and a moisture content of 0% by mass to 1.0% by mass.

The present invention relates to an active material for a lithium secondary battery, which includes a secondary particle formed by agglomeration of primary particles which include a lithium titanium composite oxide represented by Formula 1 or Formula 2, wherein a pore volume is in a range of 0.001 cm.sup.3/g to 0.05 cm.sup.3/g, and a method of preparing the same, wherein the active material for a lithium secondary battery according to the present invention may maintain an adequate pore volume even during rolling, because strength of the secondary particle is improved by controlling a particle diameter of the primary particle by introducing a metallic element.

A method is provided in which a lithium titanate precursor structure is subjected to element selective sputtering to form a lithium titanate structure including a lithium titanate core and a conformal layer on the lithium titanate core, wherein the conformal layer includes titanium oxide. A method of preparing an electrode for a lithium ion battery, wherein the electrode includes lithium titanate structures, is also provided.

Provided is a method for preparing a grain boundary insulation-type dielectric. The method includes the steps of obtaining a titanic acid compound and a ferroelectric having a value less than a melting point of the titanic acid compound; obtaining a mixture by adding the ferroelectric material to the titanic acid compound; and sintering the mixture at a temperature equal to or more than a melting point of the ferroelectric material.

Provided are a method of preparing solid electrolyte particles of Chemical Formula 1 including preparing a precursor solution by mixing a titanium precursor, a lanthanum precursor, and a lithium precursor in an aqueous or organic solvent, and heat treating the precursor solution, solid electrolyte particles prepared thereby, and a lithium secondary battery including the solid electrolyte particles:
Li.sub.3xLa.sub.(2/3-x)TiO.sub.3(0<x<0.16).<Chemical Formula 1> According to a method of preparing solid electrolyte particles according to an embodiment of the present invention, solid electrolyte particles may be easily prepared by heat treating at low temperature for a short period of time.

Provided is a lepidocrocite-type titanate capable of suppressing the interference with the curing of a thermosetting resin and a resin composition having excellent wear resistance. A lepidocrocite-type titanate has a layered structure formed by chains of TiO.sub.6 octahedra, wherein part of Ti sites is substituted with ions of two or more metals selected from the group consisting of Li, Mg, Zn, Ni, Cu, Fe, Al, Ga, and Mn and runs of at least one metal selected from alkali metals other than Li are contained between layers of the layered structure.

Negative electrode active material particles for a lithium ion secondary battery include base material particles and a coating. The coating covers a surface of the base material particles. The base material particles contain a first carbon material. The coating contains lithium titanate and a second carbon material. When a ratio of an intensity of a D band to an intensity of a G band in a laser Raman spectrum is set as an R value, the second carbon material has a larger R value than the first carbon material.

A composite powder in which highly dispersed metal oxide nanoparticle precursors are supported on carbon is rapidly heated under nitrogen atmosphere, crystallization of metal oxide is allowed to progress, and highly dispersed metal oxide nanoparticles are supported by carbon. The metal oxide nanoparticle precursors and carbon nanoparticles supporting said precursors are prepared by a mechanochemical reaction that applies sheer stress and centrifugal force to a reactant in a rotating reactor. The rapid heating treatment in said nitrogen atmosphere is desirably heating to 400 C. to 1000 C. By further crushing the heated composite, its aggregation is eliminated and the dispersity of metal oxide nanoparticles is made more uniform. Examples of a metal oxide that can be used are manganese oxide, lithium iron phosphate, and lithium titanate. Carbons that can be used are carbon nanofiber and Ketjen Black.