Abstract: The graphene(GNS)/Co-Ni layered double hydroxides(LDH) composites were synthesized through a chemical co-precipitation process of Co²⁺ and Ni²⁺ using NH₃·H₂O as a precipitator in the presence of graphene.The compositions,microstructures and morphologies of these samples were systematically characterized by Fourier transform infrared(FT-IR) spectroscopy,X-ray diffraction(XRD),field emission scanning electron microscopy(FE-SEM) and nitrogen adsorption(BET).The electrochemical performance of these composites was investigated by cyclic voltammetry and constant current charge/discharge techniques.It is found that Co-Ni LDH nanoparticles are well dispersed on the surface of GNS as the spacer to prevent the GNS from aggregation and improve the conductivity and structure stability of the Co-Ni LDH.The results show that the GNS/Co-Ni LDH electrode exhibits excellent electrochemical performance.Its specific capacitance as a single electrode is up to 2770 F/g and remains about 93.4% of the initial value after 500 potential cycles at the current density of 1 A/g.