Abstract: The precursor MnxNiyCozCO3 of a ternary material has been synthesized by carbonate co-precipitation method，using manganese sulfate，cobalt sulfate，and nickel sulfate（with the mass ratio of 0.54∶0.13∶0.13） as raw materials for metallic ions，and ammonium bicarbonate solution with a certain concentration as a precipitant.The effects of reaction temperature， concentration of ammonium bicarbonate solution，and concentration ratio of sulfate mixed solution and ammonium bicarbonate solution on sulfate conversion rate were investigated.It was found that sulfate conversion rate was as high as 91.20% when the concentration ratio of sulfate and ammonium bicarbonate solution was 1∶5 and the concentration of ammonium bicarbonate solution was 0.3 mol/L.The as-prepared MnxNiyCozCO3 had same phase as that of MnCO3 through XRD.SEM result showed the morphology of product was uniform micro-spheres（at 4~6 μm）.The method is simple，effective and applicable. Therefore，it can be used for large scale preparation of ternary material precursors.

Key words: ternary material, precursor, inorganic synthesis, micro-spheres