Self-supported NiCo2O4@Ni1.18S core-shell nanocomposite were synthesized on nickel foams by uniform growth Ni1.18S nanosheets encircling NiCo2O4 nanoneedles. Characterization results demonstrate that NiCo2O4@Ni1.18S core-shell nanocomposite have significant advantages in one - and two-dimensional nanostructure coordination structure, with richer REDOX active sites and more energy storage paths. Density functional theory (DFT) calculations results indicate that the surficial adsorption energy with OH– ions is enhanced in NiCo2O4@ Ni1.18S nanocomposite, thereby facilitating the reversible redox reaction kinetics and the electrochemical activity. As a result, self-supported NiCo2O4@Ni1.18S core-shell nanocomposite exhibit excellent energy-storage properties, i.e.: the specific charge capacity of 3158 F g−1 at 1 A g−1, high rate performance of 52.3 % from 1 A g-1 to 5 A g-1, and the 81.25% capacity retention rate after 5000 cycles. Especially, it should be pointed out that the hybrid supercapacitors assembled from self-supported NiCo2O4@Ni1.18S core-shell nanocomposite and activated carbon present the wide voltage window (0-1.6V), high energy density of 100.3 Wh kg−1 at power density of 177 W kg−1 and prospective commercial consideration. These facts fully prove the practical feasibility of self-supported NiCo2O4@Ni1.18S core-shell nanocomposite in advanced energy-storage facilities.