York-shell structured silicon-carbon composite, process for preparing the same, and negative electrode active material comprising the same

Abstract

This invention relates to a silicon-carbon composite with an eggshell-like structure, its preparation method, and a negative electrode active material comprising the same. The silicon-carbon composite with an eggshell-like structure according to embodiments of the invention can be prepared without the use of strong acids. Uniform pores are formed by using a uniformly thick inorganic layer as a sacrificial layer, thereby accommodating the volume expansion of silicon when used as a negative electrode active material, thus suppressing the peeling of the outermost carbon film. As a result, the reduction in battery performance and lifespan can be suppressed.