Performance of LiCuxMn2-xO4(0≤x≤0.10) Cathode Materials Prepared by a Fameless Combustion Synthesis

Copper-doped lithium manganese spinel LiCu x Mn 2-x O 4 (0 ≤ x ≤ 0.10) as lithium ion cathode material were synthesized by a fameless combustion synthesis at 500 °C for 3 h, two-stage calcination at 600 °C for 3 h. The phase composition was determined by X-ray diffraction (XRD), which indicated that all samples exhibited a single spinel structure except that LiCu 0.08 Mn 1.92 O 4 had a little impurity of Mn 3 O 4 . Micro-morphology of the materials were characterized by scanning electron microscopy (SEM), suggesting particle size of samples was nearly uniform when copper-doped amount x ranged from 0 to 0.06, the particle of LiCu 0.08 Mn 1.92 O 4 and LiCu 0.10 Mn 1.90 O 4 more seriously agglomerated together than that of other samples. The cycle performance tests indicated that the sample LiCu 0.06 Mn 1.94 O 4 had the highest initial discharge specific capacity of 128.1 mA h . g -1 and the 150 th capacity retention was 70.1% at 0.2 C rate. Cyclic voltammetry and electrochemical impedance spectroscopy of the sample LiCu 0.06 Mn 1.94 O 4 illustrated that appropriate copper-doped modification can improve electrochemical reversibility as well as suppress electrochemical impedance.