Stud y of the c apacitance behav ior of Ni and Ni-Cg electrod es in aqu eous and non-aque ous electrolytes b y electrochemical impedance spectroscopy

A new technology, the sup ercapacitor, has emerged with the potential to enable major advances in energ y storage. Supercapacitors are governed by th e same fundamental equations as conventional capacitors, bu t utilize hi gher surfac e area elect rodes and t hinner dielectrics to achieve greater capacitances. The nature of electr olytes plays a very im portant role in the electroc hemical ch aracteristics of superc apacitors. Generally, there are m ainly two types of electrolytes used in supercapacitor technology: aq ueous and non-aqueou s electrolytes. The resistance of electrolytes can limit power density of supercapacitor cells ( p=v۲/۴R), wh ile their operati ng voltage, restricted by the bre akdown p otential of the electrolyte, can limit the energy density (...).. In this rese arch work, a new comp osite mate rial (nickel/graphite carbon, Ni-Cg) w as develope d for supercapacitors. Ni-Cg was produced by electrolytic co-deposition of Ni ions and graphite on copper substrates. The surfac e morpholo gy was examined by SE M and EDX, and the electroch emical pro perties were tested by cyclic voltam metry (CV) and electrochemical impedance spectroscopy (EIS) in aqueous and non-aqueous electrolyt es.

کلیدواژه ها:

Super capacitor ، N ickel/carbo n graphite (Ni-Cg) co mposite ، ele ctrolyte ، EIS