Spherical LiMn 2 O 4 Spray-drying method Dynamic sintering Lithium ion battery Spherical LiMn 2 O 4 particles were successfully synthesized by dynamically sintering spherical precursor powders, which were prepared by a slurry spray-drying method. The effect of the sintering process on the morphology of LiMn 2 O 4 was studied. It was found that a one-step static sintering process combined with a spray-drying method could not be adopted to prepare spherical products. A two-step sintering procedure consisting of completely decomposing sprayed precursors at low temperature and further sintering at elevated temperature facilitated spherical particle formation. The dynamic sintering program enhanced the effect of the two-step sintering process in the formation of spherical LiMn 2 O 4 powders. The LiMn 2 O 4 powders prepared by the dynamic sintering process, after initially decomposing the spherical spray-dried precursor at 180 ยฐC for 5 h and then sintering it at 700 ยฐC for 8 h, were spherical and pure spinel. The as-prepared spherical material had a high tap density (ca. 1.6 g/cm 3 ). Its specific capacity was about 117 mAh/g between 3.0 and 4.2 V at a rate of 0.2 C. The retention of capacity for this product was about 95% over 50 cycles. The rate capability test indicated that the retention of the discharge capacity at 4C rate was still 95.5% of its 0.2 rate capacity. All the results showed that the spherical LiMn 2 O 4 product made by the dynamic sintering process had a good performance for lithium ion batteries. This novel method combining a dynamic sintering system and a spray-drying process is an effective synthesis method for the spherical cathode material in lithium ion batteries.