A method of preparing hollow molybdate composite microspheres includes steps of: (1) dissolving 1-4 mmol of MCl.sub.2 in 20 ml of water to obtain a solution A and dissolving 1-4 mmol. of molybdic acid in 20 ml of water to obtain a solution B, followed by mixing the solution A and the solution B, in which M is Co, Ni, or Cu; (2) dissolving 10-40 mmol of urea in 40 ml of water, adding the mixed solution of step (1) and stirring uniformly; (3) placing the mixed solution of step (2) into a reaction vessel and reacting at 120-160° C. for 6-12 hours; (4) suction filtrating and water washing, followed by drying in a vacuum oven at 40-60° C.; (5) calcination at 350-500° C. for 2-4 hours in a Muffle furnace.

The present invention relates to silicon-compound-coated fine metal particles, with which surfaces of fine metal particles, composed of at least one type of metal element or metalloid element, are at least partially coated with a silicon compound and a ratio of Si—OH bonds contained in the silicon-compound-coated fine metal particles is controlled to be 0.1% or more and 70% or less. By the present invention, silicon-compound-coated fine metal particles that are controlled in dispersibility and other properties can be provided by controlling the ratio of Si—OH bonds or the ratio of Si—OH bonds/Si—O bonds contained in the silicon-compound-coated fine metal particles. By controlling the ratio of Si—OH bonds or the ratio of Si—OH bonds/Si—O bonds, a composition that is more appropriate for diversifying applications and targeted properties of silicon-compound-coated fine metal particles than was conventionally possible can be designed easily.

A disordered rocksalt lithium metal oxide and oxyfluoride as in manganese-vanadium oxides and oxyfluorides well suited for use in high capacity lithium-ion battery electrodes such as those found in lithium-ion rechargeable batteries. A lithium metal oxide or oxyfluoride example is one having a general formula: Li.sub.xM′.sub.aM″.sub.bO.sub.2-yF.sub.y, with the lithium metal oxide or oxyfluoride having a cation-disordered rocksalt structure of one of (a) or (b), with (a) 1.09≤x≤1.35, 0.1≤a≤0.7, 0.1≤b≤0.7, and 0≤y≤0.7; M′ is a low valent transition metal and M″ is a high-valent transition metal; and (b) 1.1≤x≤1.33, 0.1≤a≤0.41, 0.39≤b≤0.67, and 0≤y≤0.3; M′ is Mn; and M″ is V or Mo. The oxides or oxyfluorides balance accessible Li capacity and transition metal capacity. An immediate application example is for high energy density Li-cathode battery materials, where the cathode energy is a key limiting factor to overall performance. The second structure (b) is optimized for maximal accessible Li capacity.

This application provides a lithium-ion battery and an apparatus. The lithium-ion battery includes an electrode assembly and an electrolyte. The electrode assembly includes a positive electrode plate, a negative electrode plate, and a separator. A positive active material of the positive electrode plate includes Li.sub.x1Co.sub.y1M.sub.1-y1O.sub.2-z1Q.sub.z1, where 0.5≤x1≤1.2, 0.8≤y1≤1.0, 0≤z1≤0.1, M is selected from one or more of Al, Ti, Zr, Y, and Mg, and Q is selected from one or more of F, Cl, and S. The electrolyte contains an additive A that is a polynitrile six-membered nitrogen-heterocyclic compound with a relatively low oxidation potential. The lithium-ion battery has superb cycle performance and storage performance, especially under high-temperature and high-voltage conditions.

The present disclosure is related to a positive electrode active material for lithium secondary batteries, a method for preparing the positive electrode active material, and a lithium secondary battery including the positive electrode active material. The positive electrode active material for lithium secondary batteries includes an overlithiated layered oxide (OLO), and the overlithiated layered oxide includes primary particles having a size in a range of 300 nm to 10 μm in an amount ranging from 50 to 100% by volume with respect to the total overlithiated layered oxide.

A hydroprocessing catalyst or catalyst precursor has been developed. The catalyst is a poorly crystalline transition metal molybdotungstate material or a metal sulfide decomposition product thereof. The hydroprocessing using the crystalline ammonia transition metal molybdotungstate material may include hydrodenitrification, hydrodesulfurization, hydrodemetallation, hydrodesilication, hydrodearomatization, hydroisomerization, hydrotreating, hydrofining, and hydrocracking.

Disclosed is a lithium-cobalt based complex oxide represented by Formula 1 below including lithium, cobalt and manganese wherein the lithium-cobalt based complex oxide maintains a crystal structure of a single O3 phase at a state of charge (SOC) of 50% or more based on a theoretical amount:
Li.sub.xCo.sub.1-y-zMn.sub.yA.sub.zO.sub.2(1) wherein 0.95x1.15, 0<y0.3 and 0z0.2; and A is at least one element selected the group consisting of Al, Mg, Ti, Zr, Sr, W, Nb, Mo, Ga, and Ni, wherein the at least one element of A is Mg.

A thermoelectric conversion material having a high dimensionless figure of merit ZT includes: a large number of polycrystalline grains which include a skutterudite-type crystal structure containing Yb, Co, and Sb; and an intergranular layer which is between the neighboring polycrystalline grains and includes crystals in which an atomic ratio of O to Yb is more than 0.4 and less than 1.5. A method for manufacturing a thermoelectric conversion material includes: a weighing step; a mixing step; a ribbon preparation step by rapidly cooling and solidifying a melt of the raw materials by using a rapid liquid cooling solidifying method; a first heat treatment step including heat treating in an inert atmosphere with an adjusted oxygen concentration; a second heat treatment step including heat treating in a reducing atmosphere; and manufacturing the thermoelectric conversion material by a pressure sintering step in an inert atmosphere.

A method of preparing a positive electrode active material includes mixing a lithium raw material and a nickel-containing transition metal hydroxide precursor containing nickel in an amount of 65 mol % or more based on a total number of moles of transition metals and performing a first heat treatment to prepare a nickel-containing lithium transition metal oxide. The method also includes mixing a boron and carbon-containing raw material and a cobalt-containing raw material with the nickel-containing lithium transition metal oxide to form a mixture, and performing a second heat treatment on the mixture to form a coating material including B and Co on a surface of the lithium transition metal oxide. A positive electrode active material prepared by the preparation method is formed, and a positive electrode for a lithium secondary battery and a lithium secondary battery which include the positive electrode active material.

An object of the present invention is to provide an ultraviolet and/or near-infrared shielding agent composition for transparent material using silicon compound-coated silicon-doped zinc oxide particles that are controlled in properties in an ultraviolet region and/or a near-infrared region. The present invention provides an ultraviolet and/or near-infrared shielding agent composition for transparent material used for a purpose of shielding ultraviolet rays and/or near-infrared rays, the ultraviolet and/or near-infrared shielding agent composition for transparent material featuring that the ultraviolet and/or near-infrared shielding agent contains silicon compound-coated silicon-doped zinc oxide particles, with which surfaces of silicon-doped zinc oxide particles that are zinc oxide particles doped with at least silicon are at least partially coated with a silicon compound.