NOVELTY - Producing (M1) lithium-containing transition metal sulfide involves mixing transition metal sulfide with lithium-containing compound; heating resultant mixture to effect evolution of sulfur from transition metal sulfide; and allowing sufficient time for resulting lithium-containing transition metal sulfide to form, where sulfur is retained within reaction vessel for reaction with lithium-containing compound.    USE - For producing lithium-containing transition metal sulfide used in the preparation of electrode used, in conjunction with a counter electrode and an electrolyte, in low voltage rechargeable battery power source (claimed) for e.g. in mobile phones, vehicles, laptop computers, computer games, cameras, personal CD and DVD players, drills, screw drivers, flash lights, other hand-held tools, electrochemical cell and appliances.    ADVANTAGE - The method is conducted under non-oxidizing atmosphere and/or reducing conditions to improve the yield and efficiency of reaction. The use of very small amount of mineraliser (particularly, alkali metal halide) results in lithium-containing transition metal sulfide product that exhibits enhanced crystallinity with lower levels of impurities.    DETAILED DESCRIPTION - Producing (M1) lithium-containing transition metal sulfide involves mixing transition metal sulfide with lithium-containing compound; heating resultant mixture to effect evolution of sulfur from transition metal sulfide; and allowing sufficient time for resulting lithium-containing transition metal sulfide to form, where sulfur is retained within reaction vessel for reaction with lithium-containing compound and further where lithium-containing compound is selected from lithium oxide, lithium carbonate, anhydrous lithium hydroxide, lithium hydroxide monohydrate, lithium oxalate, lithium nitrate and any material that is precursor for any of these lithium-containing compounds during heating step. INDEPENDENT CLAIMS are included for the following:    (1) use of lithium transition metal sulfides formed by the method (M1) together with binder and solvent comprising non-polar low molecular weight hydrocarbon, in the preparation of electrode; and    (2) lithium ion battery comprising a cathode comprising the electrode.