Charge–discharge curves and discharge capacities of LiNi1−yCoyO2 synthesized from lithium carbonate and nickel and cobalt oxides

LiNi1−yCoyO2 (y=0.1, 0.3, and 0.5) were synthesized by a solid-state reaction method at 800 °C and 850 °C using Li2CO3, NiO, and Co3O4 as the starting materials. The electrochemical properties of the synthesized LiNi1−yCoyO2 were then investigated. For samples with the same composition, the particles synthesized at 850 °C were larger than those synthesized at 800 °C. The particles of all the samples synthesized at 850 °C were larger than those synthesized at 800 °C. LiNi0.5Co0.5O2 synthesized at 850 °C had the largest first discharge capacity (159 mA h/g), followed in order by LiNi0.7Co0.3O2 synthesized at 800 °C (158 mA h/g) and LiNi0.9Co0.1O2 synthesized at 850 °C (151 mA h/g). LiNi0.9Co0.1O2 synthesized at 850 °C had the best cycling performance with discharge capacities of 151 mA h/g at n=1 and 156 mA h/g at n=5.