Al-doped LiMn2O4 cathode materials synthesized by a newly developed wet-milling method and a dry process method using a conventional solid-state reaction were evaluated physicochemically and electrochemically. In the wet-milling method, a precursor was made from the raw materials atomized by a wet milling. A good cyclic performance was obtained for the LiMn2O4 samples prepared by the wet-milling method, achieved up to 99% of retention of capacity at 50°C at the 30th cycle. The precursor obtained by the wet-milling method was well homogenous and highly reactive due to their finely ground particles, giving good crystallinity to LiMn2O4 products.