Polycrystalline silicon is produced in a chemical vapour deposition reactor, wherein, outside the reactor at at least one position on at least one reactor component, vibrations of the reactor are measured using a measurement device and optionally recorded. The vibrations may be used to identify rod fall over and other events occurring within the reactor.

Powder comprising particles comprising a matrix material and silicon-based domains dispersed in this matrix material, whereby the matrix material is carbon or a material that can be thermally decomposed to carbon, whereby either part of the silicon-based domains are present in the form of agglomerates of silicon-based domains whereby at least 98% of these agglomerates have a maximum size of 3 μm or less, or the silicon-based domains are not at all agglomerated into agglomerates.

Powder comprising particles comprising a matrix material and silicon-based domains dispersed in this matrix material, whereby the matrix material is carbon or a material that can be thermally decomposed to carbon, whereby either part of the silicon-based domains are present in the form of agglomerates of silicon-based domains whereby at least 98% of these agglomerates have a maximum size of 3 μm or less, or the silicon-based domains are not at all agglomerated into agglomerates.

A process for obtaining hexachlorodisilane and uses for the same. The process includes contacting at least one partially hydrogenated chlorodisilane of general formula H.sub.xSi.sub.2Cl.sub.(6-x) where x is from 1 to 5 in the liquid state with a solid non-functionalized adsorber material that is selected from the group comprising silicates, aluminosilicates, organic polymer and/or combinations thereof. The process also includes optionally separating the hexachlorodisilane and/or optionally separating the adsorber material.

A process for obtaining hexachlorodisilane and uses for the same. The process includes contacting at least one partially hydrogenated chlorodisilane of general formula H.sub.xSi.sub.2Cl.sub.(6-x) where x is from 1 to 5 in the liquid state with a solid non-functionalized adsorber material that is selected from the group comprising silicates, aluminosilicates, organic polymer and/or combinations thereof. The process also includes optionally separating the hexachlorodisilane and/or optionally separating the adsorber material.

An anode active material for use within an anode of a lithium-ion battery along with a method or process for preparing the same. Where the anode active material includes one or more non-aggregated silicon particles having BET surface areas of 0.2 to 10.0 m.sup.2/g (determination according to DIN 66131 (with nitrogen), a chloride content of 220 to 5000 ppm and a volume-weighted particle size distribution having diameter percentiles d.sub.50 of 0.5 μm to 10.0 μm.

The invention relates to a process and an apparatus for controlled preparation of octachlorotrisilane from monomeric chlorosilanes, by subjecting the chlorosilanes to a thermal plasma.

The invention relates to a process and an apparatus for controlled preparation of octachlorotrisilane from monomeric chlorosilanes, by subjecting the chlorosilanes to a thermal plasma.

Hollow bodies having a silicon-comprising shell, are produced by, in a gas comprising at least one silane of the general formula Si.sub.nH.sub.2n+2−mX.sub.m with n=1 to 4, m=0 to 2n+2 and X=halogen, (a) generating a non-thermal plasma by an AC voltage of frequency f, or operating a light arc, or introducing electromagnetic energy in the infrared region into the gas, giving a resulting phase which (b) is dispersed in a wetting agent and distilled, and then (c) the distillate is contacted at least once with a mixture of at least two of the substances hydrofluoric acid, nitric acid, water, giving a solid residue comprising hollow bodies having a silicon-comprising shell after the conversion reaction of the distillate with the mixture has abated or ended.

Hollow bodies having a silicon-comprising shell, are produced by, in a gas comprising at least one silane of the general formula Si.sub.nH.sub.2n+2−mX.sub.m with n=1 to 4, m=0 to 2n+2 and X=halogen, (a) generating a non-thermal plasma by an AC voltage of frequency f, or operating a light arc, or introducing electromagnetic energy in the infrared region into the gas, giving a resulting phase which (b) is dispersed in a wetting agent and distilled, and then (c) the distillate is contacted at least once with a mixture of at least two of the substances hydrofluoric acid, nitric acid, water, giving a solid residue comprising hollow bodies having a silicon-comprising shell after the conversion reaction of the distillate with the mixture has abated or ended.