Synthesis and Application of NaNi0.5Ti0.5O2 as Electrode Material for Sodium Ion Batteries

In this work, NaNi0.5Ti0.5O2 cathode materials of sodium ion batteries were synthesized by a pre-milling combined with solid-state reaction method using sodium hydroxide (NaOH), nickel (II) acetate (2(CH3COO)Ni.4H2O), and titanium dioxide (TiO2) as the precursors. Results of X-ray diffraction analysis of the materials obtained after the milling and calcination processes revealed that the increment of the pre-milling time improved the reactivity of NaOH and TiO2, thereby significantly reduced the content of NiO impurity in the NaNi0.5Ti0.5O2 product. The as-synthesized cathode material possessed an excellent electrochemical performance with 77% capacity (compared to the second cycle) retained after 50 cycles of charge/discharge, and 60% capacity retention when the rate of charge/discharge increased from 0.5 to 8 C.