Effects of the ratio of manganese and nickel components on the characteristics of Lix(MnyNi1−y)Oz cathode powders prepared by spray pyrolysis

Abstract The effects of the ratio of manganese and nickel components on the characteristics of Li x (Mn y Ni 1− y )O z cathode powders prepared by spray pyrolysis are investigated. The LiMn 2 O 4 , LiMn 1.5 Ni 0.5 O 4 and LiNi 0.5 Mn 0.5 O 2 cathode powders have spherical shape and non-agglomeration characteristics even after post-treatment. However, the spherical shape of the cathode powders disappeared with increasing the content of nickel component into the Li x (Mn y Ni 1− y )O z cathode powders. The mean crystallite sizes of the LiMn 2 O 4 and LiMn 1.5 Ni 0.5 O 4 cathode powders with spinel crystal structure are each 50 and 42 nm. The mean crystallite sizes of the LiNiO 2 , LiNi 0.75 Mn 0.25 O 2 and LiNi 0.5 Mn 0.5 O 2 cathode powders with layered crystal structures are 40, 30 and 17 nm, respectively. The initial discharge capacity of the spherical shape LiMn 2 O 4 powders is 121 mAh/g. The initial discharge capacities of the powders increased with increasing the nickel content into the Li x (Mn y Ni 1− y )O z cathode powders up to 206 mAh/g.