Synthesis and Electrochemical Properties of High Density LiNi0.8Co0.2-xTixO2 for Lithium-Ion Batteries

LiNi0.8Co0.2-xTixO2(0 <= x <= 0.1) powders with a high tap density have been successfully prepared using a eutectic molten salt of 0.62LiNO(3)-0.38LiOH, with a melting point of 175.7 degrees C, and Co-doped Ni(OH)(2) and TiO2, where the ratio of Li/(Ni+Co+Ti) is controlled at 1.1:1. The tap density of the synthesized LiNi0.8Co0.2-xTixO2 reaches 3.17 g cm(-3). X-ray diffraction analysis shows that this material has a well-developed layered structure. Scanning electron microscopy indicates that the synthesized particles distribute evenly. Charge-discharge tests demonstrate that the LiNi0.8Co0.15Ti0.05O2 cathode prepared at 800 degrees C has an initial discharge capacity as high as 169 mAh g(-1) and excellent capacity retention at a current density of 0.2 C in the range of 3.0-4.3 V. A capacity of 161 mAh g(-1) is retained after 50 charge-discharge cycles, with a capacity retention of 95.3%.