The possible improvements in structural stability and capacity of nickel-cobalt-aluminium cathode material were investigated by synthesizing this compound with various lithium amounts (Li x (Ni 0.80 Co 0.15 Al 0.05)O 2 where x = 0.90, 0.95, 1.00 and 1.05). An ultrasound-assisted co-precipitation method was performed to produce spherical, nanosized powders with a narrow size distribution which satisfies a homogeneous and dense film during calendaring. Layered Li x (Ni 0.80 Co 0.15 Al 0.05)O 2 (x = 0.90, 0.95, 1.00 and 1.05) cathode active materials were successfully synthesized with this method and chemical compositions of the powders synthesized were determined by inductively coupled plasmamass spectroscopy. Structural characterization was carried out via X-ray diffraction and scanning electron microscopy techniques. The electrochemical properties of the cathode materials were investigated by electrochemical impedance spectroscopy, galvanostatic charge/discharge and cyclic voltammetry methods. Among the cathode compositions in the current study, Li 1.05 (Ni 0.80 Co 0.15 Al 0.05)O 2 exhibited the highest capacity, 138 mAh g −1 with 95% capacity retention upon 22 cycles.