The formation of Ni3S2 was realized by mechanical alloying with metallic nickel and sulfur powder as precursors. The products were characterized by X-ray diffraction, thermoanalysis, and scanning electron microscopy. Electrochemical properties of Li/P(EO)(20)Li(CF3SO2)(2)N-10 wt % gamma-LiAlO2/Ni3S2 cells were also presented. The initial discharge capacity of Ni3S2 was 304 mAh g(-1), with a platform at about 1.4 V vs Li/Li+. A capacity fading rate of 0.5% per cycle was achieved within 100 cycles. The charge-discharge mechanism of Ni3S2 was implied by the analysis of the charge-discharge potential profiles, the cyclic voltammetry traces, and the ex situ XRD patterns of the Ni3S2 cathode. (c) 2006 The Electrochemical Society.