Synthesis of Li-x(Ni0.80Co0.15Al0.05)O-2 cathodes with deficient and excess lithium using an ultrasonic sound-assisted co-precipitation method for Li-ion batteries
Abstract
The possible improvements in structural stability and capacity of nickel-cobalt-aluminium cathode material were investigated by synthesizing this compound with various lithium amounts (Lix (Ni0.80Co0.15Al0.05)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(Ni0.80Co0.15Al0.05)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 plasma-mass 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(Ni0.80Co0.15Al0.05)O-2 exhibited the highest capacity, 138 mAh g(-1) with 95% capacity retention upon 22 cycles.