A method for preparing a positive electrode active material, a positive electrode active material prepared using the same, and a lithium secondary battery, and in particular, to a method for preparing a positive electrode active material comprising the steps of (a) preparing a coating composition including a precursor of metal-phosphorous-oxynitride; (b) forming a precursor layer on a positive electrode active material with the coating composition of (a) using a solution process; and (c) forming a metal-phosphorous-oxynitride protective layer on the positive electrode active material by heat treating the positive electrode active material having the precursor layer formed thereon. The method for preparing a positive electrode active material uses a solution process, which is advantageous in terms of simplifying the whole process and reducing costs, and high capacity, high stabilization and long lifetime are obtained as well by the formed protective layer having excellent properties.

A method for preparing a positive electrode active material, a positive electrode active material prepared using the same, and a lithium secondary battery, and in particular, to a method for preparing a positive electrode active material comprising the steps of (a) preparing a coating composition including a precursor of metal-phosphorous-oxynitride; (b) forming a precursor layer on a positive electrode active material with the coating composition of (a) using a solution process; and (c) forming a metal-phosphorous-oxynitride protective layer on the positive electrode active material by heat treating the positive electrode active material having the precursor layer formed thereon. The method for preparing a positive electrode active material uses a solution process, which is advantageous in terms of simplifying the whole process and reducing costs, and high capacity, high stabilization and long lifetime are obtained as well by the formed protective layer having excellent properties.

A polymeric lithium phosphorus oxynitride (LiPON) battery can be prepared by reacting a polymetaphosphonic acid with an organolithium compound to provide a reaction product of LiPON and including the reaction product in the LiPON battery. The LiPON is soluble in solvents selected from the group consisting of dimethyl sulfoxide (DMSO), tetrahydrofuran (THF), toluene and N-methylpyrrolidone (NMP).

Provided is a nitride phosphor having two or more maximum absorption points in a range of 3,200 to 3,300 cm.sup.−1 in an infrared absorption (FT-IR) spectrum. The nitride phosphor of the present invention has excellent emission characteristics and is highly reliable when used in devices.

Provided is a nitride phosphor having two or more maximum absorption points in a range of 3,200 to 3,300 cm.sup.−1 in an infrared absorption (FT-IR) spectrum. The nitride phosphor of the present invention has excellent emission characteristics and is highly reliable when used in devices.

An apparatus for manufacturing a quantum dot is provided, the apparatus including a first supplying part that provides a cationic precursor, a second supplying part that provides an anionic precursor, a mixing part connected to the first supplying part and the second supplying part, and a reaction part including a reaction tube configured to receive a liquid mixture of the cationic precursor and the anionic precursor from the mixing part and a first microwave generator configured to provide a microwave that is transmitted through the reaction tube. Therefore, the apparatus may produce a quantum dot of multi-element compounds.

An apparatus for manufacturing a quantum dot is provided, the apparatus including a first supplying part that provides a cationic precursor, a second supplying part that provides an anionic precursor, a mixing part connected to the first supplying part and the second supplying part, and a reaction part including a reaction tube configured to receive a liquid mixture of the cationic precursor and the anionic precursor from the mixing part and a first microwave generator configured to provide a microwave that is transmitted through the reaction tube. Therefore, the apparatus may produce a quantum dot of multi-element compounds.

A method for preparing a negative electrode active material, a negative electrode active material prepared using the same, and a lithium secondary battery, and in particular, to a method for preparing a negative electrode active material including the steps of (a) preparing a coating composition including a precursor of metal-phosphorus-oxynitride; (b) forming a precursor layer on a negative electrode active material with the coating composition of (a) using a solution process; and (c) forming a metal-phosphorus-oxynitride protective layer on the negative electrode active material by heat treating the negative electrode active material having the precursor layer formed thereon. The method for preparing a negative electrode active material uses a solution process, which is advantageous in terms of simplifying the whole process and reducing costs, and high capacity, high stabilization and long lifetime are obtained as well by the formed protective layer having excellent properties.

A method for preparing a negative electrode active material, a negative electrode active material prepared using the same, and a lithium secondary battery, and in particular, to a method for preparing a negative electrode active material including the steps of (a) preparing a coating composition including a precursor of metal-phosphorus-oxynitride; (b) forming a precursor layer on a negative electrode active material with the coating composition of (a) using a solution process; and (c) forming a metal-phosphorus-oxynitride protective layer on the negative electrode active material by heat treating the negative electrode active material having the precursor layer formed thereon. The method for preparing a negative electrode active material uses a solution process, which is advantageous in terms of simplifying the whole process and reducing costs, and high capacity, high stabilization and long lifetime are obtained as well by the formed protective layer having excellent properties.

To provide a method for producing a phosphoryl imide salt represented by the following general formula (1) at a satisfactory yield by cation exchange. The method comprises the step of performing cation exchange by bringing a phosphoryl imide salt represented by the following general formula (2) into contact with a cation exchange resin having M.sup.1 n+ or a metal salt represented by the general formula (4) in an organic solvent having a water content of 0.3% by mass or less.

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