Effect of morphology on the physical and electrochemical properties of the high-voltage spinel cathode LiMn1.5Ni0.5O4

Ni0.25Mn0.75CO3 precursors with different morphologies are prepared successfully by carbonate co-precipitation of the corresponding metal salt solutions using Na2CO3 and NH4OH as precipitation and complexing agents. The high-voltage spinel LiMn1.5Ni0.5O4 is then prepared as a lithium battery cathode material from this precursor by the introduction of LiOH·H2O. The effect of morphologies on the electrochemical performance was evaluated by analyzing the charge/discharge profiles and cycling and rate-capability performances. It showed that the spherical LiMn1.5Ni0.5O4 with nano-size primary particles had obviously better cycling performance (at both room and elevated temperatures) and rate capability compared to LiMn1.5Ni0.5O4 with irregular particle shape. The spherical morphology with good packing properties also results in a higher tap density.