The preparation, structural characterization and study of the electrochemical behavior in lithium cells of Co1−2y Fe y Ni y Sb3 (0.125<y≤0.5) compounds is described. The refinement of X-ray diffraction (XRD) patterns evidenced the skutterudite-type structure for all compositions, with an increasing partial filling of 2a sites. The first discharge of lithium anode cells shows two plateaus. The plateau at higher potential, which occurs at ca. 0.8V and extends from ca. 150 to 250Ah/kg depending on “y”, is mainly assigned to side reactions of lithium with the electrolyte, as confirmed by 7Li NMR. The second plateau occurs at 0.5–0.6V and is assigned to Li–Sb alloys formation. The charge of the cell shows that only the second step is reversible. Further discharge/charge cycles present a plateau at 0.8V in the discharge and at 1.05V in the charge, which agree well with the Li–Sb alloying/de-alloying process. Extended cycling results on a loss of capacity, to stabilize over 100Ah/kg after 20 cycles.