Electroactive materials for metal-ion batteries

This invention relates to particulate electroactive materials comprising a plurality of composite particles, wherein the composite particles comprise: (a) a porous carbon framework including micropores and/or mesopores having a total volume of at least 0.7 cm/g, wherein at least half of the micropore/mesopore volume is in the form of pores having a diameter of no more than 5 nm; and (b) silicon located within the micropores and/or mesopores of the porous carbon framework in a defined amount relative to the volume of the micropores and/or mesopores.