▎ 摘　　要

NOVELTY - Silicon-containing particles have a surface area of 25.8-182 m2/g as determined by Brunauer-Emmet-Teller (BET) analysis according to ISO 9277:2010, where the chemical compound of the silicon-containing particles comprises crystallite sizes of 1-15 nm as determined by the Rietveld method. USE - The silicon-containing particles is used as a particulate active material for a negative electrode of a secondary lithium-ion electrochemical cell (claimed). ADVANTAGE - The particles provide improved cycling capacity, excellent specific capacity and high charge/discharge-cycling capability. The particles have an improved coulombic efficiency as compared to particles coated or baked at lower carbonization temperatures. The active electrode material containing the silicon-containing particles enables forming secondary lithium ion batteries having relatively high cyclability, high specific capacity and high coulombic effect. The electrode material can comprise very small particles, reduce cracking, and is not so small as to give too high solid electrolyte interphase (SEI) formation or uncontrolled oxidation during production. The particles have isotropic or close to isotropic expansion, meaning the powder should not be monocrystalline, and improve coulombic efficiency, a temperature at which pure silicon nanoparticles will become crystalline. The particles are possible to charge fast also the first time of charging, and retain nearly all the high charging capacity of silicon with minimal first cycle efficiency losses. DETAILED DESCRIPTION - Silicon-containing particles have a surface area of 25.8-182 m2/g as determined by Brunauer-Emmet-Teller (BET) analysis according to ISO 9277:2010, where the silicon-containing particles comprise a chemical compound of formula: Si(1-x)Mx, and the chemical compound of the silicon-containing particles comprises crystallite sizes of 1-15 nm as determined by the Rietveld method. INDEPENDENT CLAIMS are included for the following: a method for manufacturing the multicrystalline silicon-containing particles, comprising (a) forming a homogeneous gas mixture of a first precursor gas of a silicon containing compound and at least one second precursor gas of a substitution element M containing compound, (b) injecting the homogeneous gas mixture of the first and second precursor gases into a reactor space where the precursor gases are heated to 700-900° C so that the precursor gases react and form predominantly amorphous silicon-containing particles, (c) subjecting the predominantly amorphous silicon-containing particles to a heat treatment in an inert atmosphere at 800-900° C for 0.1-4 hours to transform the amorphous silicon-containing particles to multicrystalline silicon-containing particles, and (d) cooling and collecting the multicrystalline silicon-containing particles, where the relative amounts of the first and the second precursor gases are adapted such that the formed particles obtain an atomic ratio M element: silicon of 0.005:0.25; a negative electrode of a secondary lithium-ion electrochemical cell, comprising at least one particulate active material, binder material, and a current collecting substrate, where the at least one particulate active material is embedded in the binder material to form an anode mass which is deposited as an anode mass layer onto the current collecting substrate, and the particulate active material is the silicon-containing particles; and a composite particle for use in the negative electrode in a secondary lithium-ion electrochemical cell, where the composite particle comprises the silicon-containing particle, and graphene or reduced graphene oxide, or the silicon-containing particle, and a predominantly carbon-containing nanoporous structure or a predominantly carbon-containing aerogel, or silicon-containing particle, and a predominantly carbon containing material made by pyrolysis of a carbon rich material. x=0.0005-0.20;and M=C or N.