TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Method: The method further comprises: associating the porous silicon particulates with a binding material; and controlling a thickness of the porous silicon film. The electrochemical etching step comprises: use of an acid, preferably hydrofluoric acid; and exposure of the silicon substrate to an electric current density of 1-10 mA/cm2. The gradual increase of the electric current density during the separating step comprises an increase of the electric current density by 1-2 mA/cm2 per sequential increment. The steps (a) and (b) are repeated: for more than 5 times; until the porous silicon film becomes inseparable from the silicon substrate; and until the silicon substrate develops one or more cracks. The chemical etching step occurs by exposure of the porous silicon film and the silicon substrate to a metal. The exposure step results in coating of the porous silicon film and the silicon substrate with the metal. The splitting step occurs by physical grinding, crushing, sonication, ultrasonication (preferred), ultrasonic fracture, pulverization and/or ultrasonic pulverization. The thickness of the porous silicon film is controlled by adjusting one or more parameters comprising electric current density during electrochemical etching, resistivity of the silicon substrate during electrochemical etching, concentration of electrolyte etchants used during electrochemical or chemical etching and/or temperature during electrochemical or chemical etching. Preferred Components: The silicon substrate comprises a silicon wafer. The metal comprises silver (preferred), copper, chromium, gold, aluminum, tantalum, lead, zinc and/or silicon. The pores: have diameters of at least 50 nm, less than 50 nm and/or less than 2 nm; and comprise hierarchical pores. The hierarchical pores comprise micropores and mesopores within macropores. The formed porous silicon particulates: have thicknesses of 10-200 mu m; comprise pores that span at least 50% of a thickness of the porous silicon particulates and span an entire thickness of the porous silicon particulates; and comprise diameters of 1-50 mu m. The coating comprises a metal coating. The anode material has a discharge capacity of at least 600 mAh/g (preferably at least 1000 mAh/g) over at least 50 cycles and a Coulombic efficiency of at least 90% over at least 50 cycles.    TECHNOLOGY FOCUS - POLYMERS - Preferred Components: The binding material comprises a polymer including polyacrylonitrile, pyrolyzed polyacrylonitrile, polyvinyldiene difluoride, polyacrylic acid and/or carboxymethyl cellulose, preferably carbonized polyacrylonitrile.