Influence of Al Doping Content on the Structure and Electrochemical Properties of LiNi1/3Co2/3-xAlxO2

The layerd cathode materials LiNi1/3Co2/3-xAlxO2 (x=1/12,1/6, 1/3, 1/2, 7/12) for lithium ion battery has been successfully synthesized using eutectic lithium salts of 0.38LiOH center dot H2O-0.62LiNO(3) mixed with Ni1/3Co1/3Al1/3(OH)(2) as a precursor. The materials were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and electrochemical performance tests. Results show that the LiNi(1/3)Co(2/3-x)Al(x)O(2)can be maintained as a well-layered ceNaFeO, structure in the range of 1/12 <= x <= 1/3. At x>1/3, a miscellaneous phase is present. The LiNi1/3Co1/3Al1/3O2 products have the highest crystallinity, the least cation mixing effect and the most uniform particle size with a tap-density of 2.88 g . cm(-3). Additionally, the initial discharge capacity of the product was 151.5 mAh . g(-1) and after 50 cycles. 91.4% of the initial discharge capacity was maintained. The reversible capacities of the products are 133.7 and 120.9 mAh . g(-1) at 1C and 2C discharge rates, respectively.