| 摘要 |
A process is provided for preparing a particulate material consisting of a plurality of porous particles comprising at least 40% by weight of an electroactive material selected from silicon, tin, germanium, aluminium or a mixture thereof (most preferably Si), wherein the particles are assembled from a plurality of fragments comprising the electroactive material. The particle fragments can be obtained by fragmentation of a porous precursor comprising the electroactive material, which may be in the form of spherical, or near-spherical, particles. This enables better intercalation of metal ions for use in electrode materials. The fragments may be obtained from wet ball milling of a porous precursor, while the porous precursor may be obtained by leaching an alloy comprising Si and/or Ge structures dispersed in a metal matrix. The porous particles may be assembled from the plurality of fragments and one or more other components such as conductive additives, structural additives, pore forming materials, additional particulate electroactive materials and binders. Also provided are particulate materials obtainable according to the process of the invention, compositions comprising the particulate materials, and electrodes and electrochemical cells comprising the particulate materials. |
