Properties of Li–Ni–Mn–O electrode materials prepared from solution spray synthesized powders

Li–Ni–Mn–O compounds with the nominal compositions of Li1+xNi1/2−x/2Mn1/2−x/2O2 (0 ≤ x ≤ 0.2) were prepared for the first time via the homogenous precursors produced by solution spray method. All materials were identified as a pure phase with α-NaFeO2-type layered structure (space group R-3m). Analysis of chemical composition indicated that lithium content in final products deviated somewhat from target compositions while the molar ratio of Ni vs. Mn was roughly the same as that in targets. Electrochemical investigations showed that a similar initial charge capacity of about 180 mAh/g with smooth charge–discharge curves was delivered in the voltage range of 4.5–3.0 V for all samples, but a gradual decrease in discharge capacity due to increase of irreversible capacity was observed with increasing x. The samples with 0 ≤ x ≤ 0.091 still exhibited the discharge capacities more than 140 mAh/g until 40th cycle.