TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Process: Producing lithium-containing iron sulfide involves mixing iron sulfide with lithium carbonate and carbon; heating the resultant mixture to effect evolution of sulfur from the transition metal sulfide; and allowing sufficient time for the resulting lithium-containing transition metal sulfide to form, where sulfur is retained within the reaction vessel for reaction with the lithium carbonate and further where the lithium carbonate is used directly or is formed using any material that form lithium carbonate during the heating step. The transition metal sulfide and lithium-containing compound are heated at 500-1500 degrees C. The reaction is carried out under non-oxidizing atmosphere and/or reducing conditions provided by at least one reducing gas and/or at least one reducing agent. The method further involves the addition of at least one mineraliser (1-5 wt.% of starting materials). Preferred Compounds: The lithium-containing transition metal sulfide is of formula Li2-x-yAyFe1-zMzS2. The transition metal sulfide is manganese, iron, cobalt, nickel, copper or zinc (preferably manganese, iron, cobalt or nickel). The transition metal sulfide and the lithium-containing compound are in powder form. The ratio of transition metal sulfide:lithium ion in the lithium containing material:reducing agent is 1:0.5-4 (preferably 1):0-5 (preferably 0.5) moles. The mineraliser comprises alkali metal halide. The transition metal sulfide is monosulfide and/or disulfide.x=0-1.5;y and z=0-1;A=silver, sodium, copper or potassium;M=generic representation for at least one transition metal.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Components: The reducing gas is selected from carbon monoxide, hydrogen, reforming gas (mixture of hydrogen and nitrogen), hydrogen sulfide, methane and other gaseous alkanes and the reducing agent is selected from carbon and any carbonaceous material suitable to provide a source of carbon during the heating step. The binder comprises ethylene propylene diene monomer. The solvent comprises trimethylbenzene. EXAMPLE - Lithium carbonate (111 g), iron sulfide (179 g) and carbon denka black (9 g) were weighed, this mixture was milled for 1-12 hours at rate of 200-350 rpm. The precursor mix was then pelletized, and placed into glassy carbon crucible with lid. The carbon crucible was placed into the furnace under gentle flow of an inert gas, and heated at 135-900 degrees C at rate of 3 degrees C per minute over period of 2 hours. The crucible was cooled under the inert gas flow and transferred directly into glove box. The resulting product was ground initially using pestle and mortar and then milled more finely using ball mill to give lithium-containing transition iron sulfide product.