Method of producing a battery anode active material comprising a porous host structure and silicon residing in the host pores

Abstract

A method of producing multiple particulates having pores containing Si therein, comprising: (a) providing a porous conductive host structure having from 5% to 99.9% of pores; (b) introducing a halogen gas that chemically reacts with Si at a first temperature to form a silicon halide, wherein the silicon halide is selected from SiF, SiCl, SiI, SiBr, and/or SiXZ, wherein X and Z are each a halogen element and a=1-3, b=1-3, and a+b=4; (c) vaporizing the silicon halide to form a vapor phase and directing the silicon halide vapor into pores of the host and facilitating the silicon halide to decompose into a halogen gas product and solid Si particles or coating deposited at a second temperature in the pores to form a Si-infiltrated porous host structure; and (d) optionally breaking and reducing said Si-infiltrated host structure into smaller porous particles.