Diverse single crystalline spinel LiMn 2 O 4 cathode materials are derived from spherical and cubic MnCO 3 precursors using a general pH-mediated chemical precipitation approach. With careful pre-controls over the particle properties of the MnCO 3 precursors upon pH adjustment, five LiMn 2 O 4 samples with an average size of 0.5-1.0 mm are obtained. Among these samples, the LiMn 2 O 4 prepared at a pH value of 7.0 exhibits a well-defined truncated octahedral crystal structure in which most surfaces are aligned to the {111} crystalline orientations with minimal Mn dissolution, whereas a small portion of the structure is truncated along the {110} orientations to support Li diffusion. Benefiting from the unique crystal structure, the synthesized LiMn 2 O 4 cathode manifests superior rate capability and prolonged cycle stability, especially at elevated temperatures with a capacity retention of 86.7% after 1000 cycles at 5 C under 25 C and of 80.7% after 250 cycles at 1 C under 55 C. These results demonstrate that the morphology of the MnCO 3 precursor obtained by using the precipitation method has a significant influence on the crystal structure and electrochemical properties of resultant LiMn 2 O 4 . The work described here also shows a great potential in practical industrial applications aimed towards developing high performance LiMn 2 O 4 electrode materials for lithium ion batteries.

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