Synthesis of Al-doped LiMn₂O₄ spinels by mechanical alloying and rotary heating

Al doped LiMn₂O₄ powders with narrow particle size distribution, high capacity and good cycle retention were successfully prepared by a solid-state reaction at lower temperature for a shorter heating time (600 °C for 3 h) by employing mechanical alloying and rotary heating. Mechanical alloying ensured the uniform mixing of raw materials at nanoscale together with structure defects and short diffusion distance. The stirring and tumbling movement of the powders in the rotary furnace enhanced the uniformity of temperature, chemical composition and particle size of the powders. The successfully synthesized LiAl_0.1Mn_1.9O₂ materials delivered an initial discharge capacity of 118 mAh/g up to 100 cycles, revealing a high reversible capacity and good cycleability.