Carbon-silicon composite structures and methods of fabricating thereof

Abstract

Described herein are carbon-silicon composite structures and methods of producing such structures. A carbon-silicon composite structure comprises one or more carbon-containing structures that have pores at least partially filled with silicon-containing structures. Specifically, the silicon-containing structures are attached to the pore walls while maintaining void spaces within these pores. These void spaces can accommodate silicon expansion during lithiation. Carbon-silicon composite structures can be produced by submerging carbon-containing structures into a precursor liquid solution (comprising a precursor) and driving this solution into the pores. The silicon-containing structures are then formed (from the precursor) within the pores either electrochemically (e.g., by applying a voltage to the solution and structures) or chemically (e.g., by introducing the structures into a reducing liquid solution). In some examples, these void spaces are sealed from the environment by additional structures, e.g., separate silicon-containing structures and/or carbon structures.