Electrochemical properties and preparation of LiNi0.5Mn1.5O4 cathode material by high-energy ball milling for Li-Ion batteries

The ultrafine LiNi 0.5 Mn 1.5 O 4 with excellent electrochemical performance is successfully synthesized using carbonate as precursor (NiCO 3 , MnCO 3 and Li 2 CO 3 ) by high-energy ball milling followed by double sintering method. The influence of different ball milling time and the powders synthesized by double sintering method on the phase composition, morphological characteristics and the electrochemical performance was studied. The results indicate that the LiNi 0.5 Mn 1.5 O 4 powders by ball-mill for 10 h followed by sintering at 700℃ for 5 h shows the well-ordered high crystalline with mean size of the primary nanoparticles about 100 nm, and the discharge capacity is 123.3 mAh g −1 at 0.1 C rate. Further sintering at 900℃ for 1 h, the LiNi 0.5 Mn 1.5 O 4 powders have a cubic spinel structure (Fd3m) with higher crystallinity and exhibit a narrow size distribution with the particle size around 600 nm, and the highest discharge capacity of 143.3mAh g −1 at 0.1 C rate, 96.7 % capacity retention after 50 cycles at 2 C rate, and the coulombic efficiency exceeding 98.5 %.