Synthesis and Electrochemical Properties of High Density LiNi[sub 0.8]Co[sub 0.2−x]Ti[sub x]O[sub 2] for Lithium-Ion Batteries

LiNi 0.8 Co 0.2 − x Ti x O 2 ( 0 ≤ x ≤ 0.1 ) powders with a high tap density have been successfully prepared using a eutectic molten salt of 0.62 LiNO 3 – 0.38 LiOH , with a melting point of 175.7 ° C , and Co-doped Ni ( OH ) 2 and TiO 2 , where the ratio of Li / ( Ni + Co + Ti ) is controlled at 1.1:1. The tap density of the synthesized LiNi 0.8 Co 0.2 − x Ti x O 2 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 LiNi 0.8 Co 0.15 Ti 0.05 O 2 cathode prepared at 800 ° 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%.