| CPC H01M 4/364 (2013.01) [H01M 4/386 (2013.01); H01M 4/587 (2013.01)] | 19 Claims |

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1. A method for the production of a silicon-graphite composite material, the method comprising the following steps:
(i) drying a concentrate of a silicate containing graphite material comprising a natural graphite material that has a silica/silicate naturally distributed therein;
(ii) mixing the graphite material with magnesium powder;
(iii) a reduction step comprising transferring the mixture from step (ii) to a furnace whilst subject to a flow of an inert gas, at a temperature of about 600-900° C. for about 1-4 hrs, at the conclusion of which the mixture is allowed to cool;
(iv) an oxidation step in which as the temperature cools to about 500-550° C. the inert gas flow is stopped, and air is allowed into the furnace, after which the temperature of about 500-550° C. is maintained for about 1-2 hrs, at the conclusion of which the mixture is allowed to cool to room temperature; and
(v) a leach step in HCl, as a purification step, with a residence time of between about 1-3 hrs, after which the resulting residue/powder is separated.
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