Abstract: In accordance with one exemplary embodiment of the present invention, there is a negative electrode active material for a secondary battery which includes a silicon-carbon composite that includes a carbon-based material and a first silicon-based nano-coating layer formed on the carbon-based material; silicon carbide; silicon nitride; and second silicon-based particles.

Abstract: One embodiment of the present disclosure provides a rotary microwave apparatus including: a sintering body; a microwave-permeable cylindrical rotating tube located in the sintering body and configured to mix a powder raw material while rotating in a horizontal direction; and a microwave generator connected to the sintering body and configured to radiate microwaves to the cylindrical rotating tube, wherein the cylindrical rotating tube includes a stirring unit provided on an inner circumferential surface in a longitudinal direction, and configured to mix the powder raw material while being rotated by the cylindrical rotating tube.

Abstract: The present invention provides a microwave firing apparatus including: a firing main body; a slide reaction unit located in the firing main body and configured to perform a biaxial reciprocating linear motion along two axes, namely an X-axis and a Y-axis, orthogonal to each other in a horizontal direction; and a plurality of microwave generators located on an upper surface of the firing main body, and in which individual microwave generators are arranged in parallel to the biaxial linear motion direction of the slide reaction unit.

Abstract: There are provided a negative electrode active materials including a silicon/carbon (Si/C) composite in which a silicon-based coating layer is formed on carbon-based particles, wherein the Si/C composite has a peak area ratio A2/A1 of 0.2 to 3.0 as determined by X-ray diffraction analysis, and a method of preparing a negative electrode active material for a secondary battery, which includes a pretreatment step of heat treating carbon-based particles; and a microwave sintering step of mixing silicon-based particles with the heat-treated carbon-based particles and irradiating the resulting mixture with microwaves.

Abstract: Provided is a cathode for a sodium/sulfur (NaS) battery. The cathode includes polysodium-sulfide polyacrylonitrile (NaxS-PAN, 3?x) obtained by reaction with a large amount of sodium, and is a high-capacity electrode manufactured via sodiation to inject sodium.