TECHNOLOGY FOCUS - ELECTRONICS - Preferred Components: The electrode further comprises a conductive current collector in electrical contact with the active material. The electrospun material or electrospun silica to be reduced comprises silica to be reduced comprises silica-containing particles having an aspect ratio of at least 5:1 and an smallest dimension of less than 3 microns, or reducing a particulate starting material comprising silica-containing particles comprising several elongate structural elements, each elongate structural element having an aspect ratio of at least 5:1 and an smallest dimension of less than 3 microns.    TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Components: The surface area of the silicon material is substantially the same as the surface area of the starting material. The surface area of the material comprising silicon is greater than the surface area of the starting material. The shape of the particles of the material comprising silicon is the same as the shape of the starting material particles. The starting material is n- or p-doped; or is undoped. The starting material particles have an open framework structure. The metal is magnesium or calcium. The starting material is biogenic silica. The starting material has enclosed void volume and the smallest dimension is a thickness of a wall of the starting material enclosing the void volume. Preferred Method: The silica at a surface of the starting material particles is reduced and silica at a core of the starting material particles is not reduced. The silica at the core is selectively removed. The starting material is reduced at not greater than 650 degrees C. The starting material is reduced by exposure to liquid metal or metal vapor. The reduction takes place in the presence of a thermal moderator, optionally a salt. The silica is reduced by exposure to a reducing composition that causes both reduction of the silica and doping of the silicon. The method (M1) further involves: coating at least part of the surface of the material comprising silicon. At least part of the surface of the material comprising silicon is coated with silicon oxide or carbon. The starting material is formed by electrospinning silica; is formed by electrospinning silica onto a patterned collector defining a shape for the starting material. The silica is electrospun with a polymer. The silica only is electrospun. EXAMPLE - No suitable example given.