Multi-shell structures and fabrication methods for battery active materials with expansion properties

A method comprising:

• providing particles comprising carbon;
• activating the particles in an oxygen-comprising environment at elevated temperatures to form activated particles;
• depositing silicon-comprising material on the activated particles to form silicon-comprising active material on the activated particles;
• and
• depositing a protective coating on the silicon-comprising active material and the activated particles to form composite particles, the protective coating at least partially encasing the silicon-comprising active material and the activated particles, the protective coating comprising carbon,
• wherein:
• each of the composite particles comprises curved, multi-layered graphene material, with at least some of the silicon-comprising active material coating two or more internal pores of a porous core that are defined by the curved, multi-layered graphene material.