Spinel LiMn_(2)O_(4)has been considered to be the most promising alternative cathode material for the new generation of lithium-ion batteries in terms of its low cost,non-toxicity and easy manufacture.The spinel lithium manganese mixed oxides were prepared from lithium nitrate,manganese nitrate and citric acid by a sol-gel method and were characterized by thermogravimetric analysis,X-ray diffraction,cyclic voltammetry and constant current charging-discharging technique.The different sintering temperatures for different time have strong influence on the structure,initial discharge capacity and cycling performance of the lithium manganese oxide.It shows that the lithium manganese oxides sintered at 700℃for 10 h have a single spinel structure and better electrochemical properties.The initial discharging capacity can be up to 125.9 mAh·g^(-1),even after six cycles,it still retains 109.1 mAh·g^(-1).