SURFACE COATED POROUS SILICON BASED ANODE ACTIVE MATERIAL, PREPARATION METHOD THEREOF, AND LITHIUM SECONDARY BATTERY COMPRISING THE SAME

摘要

According to an embodiment of the present invention, provided are a method for manufacturing a negative electrode active material, which comprises a step of forming an oxide coating layer on the surface of porous silicon-based particles or nanostructures by an atomic layer deposition method, and the negative electrode active material manufactured by the method. According to an embodiment of the present invention, the method for manufacturing the negative electrode active material is capable of forming a uniform and smooth coating layer, with a depth of not more than 10 nm, on the surface of porous silicon-based particles or nanostructures, which have a complex curved surface as nanostructures or a deep pore surfaces to the inside, by forming the oxide coating layer on the surface of porous silicon particles or nanostructures using the atomic layer deposition method. Therefore, uniform surface coating can be performed on the surface of the negative electrode active material and on the surface of an electrode. In addition, the present invention is capable of further enhancing lifespan characteristics of a secondary battery by preventing the formation of cracks on a SEI layer of a negative electrode or a non-reacted product layer, which may be caused by continuous expansion and contraction during charging and discharging, due to the uniform surface coating.