Evaluating the role of current collectors in supercapacitor electrodes with NiCo2O4 nanospheres

Supercapacitor as an electrochemical energy storage device is well known for delivering high power density than batteries but faces the challenge of lower electrical energy density. To overcome this limitation, researchers are exploring new and advanced nanostructured electrode materials, particularly metal oxides, and composites. Most of the supercapacitor research is focused on investigating electrode materials, which are important in determining the device's electrochemical performance. Along with this premise, this study says that a current collector (CC) plays an essential part in an electrode's electrochemical performance and is just as important as the electrode material. It is crucial to investigate the role of current collectors in supercapacitor electrode electrochemical performance. In this study, four different current collectors are used to deposit NiCo2O4 (NCO) as the active electrode material: nickel foam (Ni), flexible graphite sheet (FG), copper foil (Cu), and stainless-steel foil (SS). The electrochemical tests are performed with and without active material loaded on different CCs and investigated for the contribution made by each CC. Results indicate that Ni foam possesses its own specific capacity of 128 Fg-1 and as an electrode, NCO–Ni delivered the highest specific capacity of 960 Fg-1 at a current density of 1 Ag-1, compared with NCO-FG (237 Fg−1), NCO–Cu (169 Fg−1), and NCO-SS (64 Fg−1) electrodes.