Abstract: Method for producing a powder comprising particles (26) comprising amorphous, micro- or nano-crystalline Silicon nitride. The method comprises the steps of supplying a reactant gas (12) containing Silicon, and a reactant gas (12) containing Nitrogen, to a reaction chamber (16) of a reactor (10), and heating said reactant gases (12) to a temperature in the range of 510° C. to 1300° C. which is sufficient for thermal decomposition or reduction of the reactant gases (12) to take place inside the reaction chamber (16) to thereby produce a powder of amorphous, micro- or nano-crystalline particles (26) comprising Silicon nitride (SiNx) in which the atomic ratio of Silicon to Nitrogen is in the range 1:0.2 to 1:0.9. The produced powder of particles (26) may be used to produce a film, an electrode, such as an anode, for a battery, such as a Lithium ion battery.