Abstract: The product LiMn1.5Ni0.5-xCuxO4 with cubic spinel structure was synthesized by a chemical co-precipication method. MnSO4·H2O, NiSO4·6H2O, CuCl2·2H2O, NaOH, NH3·H2O and LiOH·H2O were used as the initial materials. The LiMn1.5Ni0.5-xCuxO4 powder was characterized by X-ray diffraction, scanning electron microscopy, tap density testing and electrochemical testing. The LiMn1.5Ni0.5-xCuxO4 material synthesized by two-stage process delivers a discharge capacity of 129.4 mAh·g-1 and 127.1 mAh·g-1 in the range of 3.0-5.0 V at the discharge current density of 0.50 mA·cm-2 and 2.00 mA·cm-2 individually. The material synthesized by three-stage process has a perfect cycle performance. Its discharge capacity can retain more than 98% of the initial capacity after 50 cycles between 3.0 and 5.0 V. Tap density of the material synthesized by three-stage process reaches 2.1 g·cm-3. In addition, the cycle performance of material synthesized was discussed with graphite as the anode. The average numerical decrement of discharge capacity is 1.7‰ after 200 cycles at the discharge current density of 2.00 mA·cm-2.

Key words: Lithiumion battery, Co-precipitation, 5 V Cathode material, Spinel LiMn1.5Ni0.5-xCuxO4