The effect of intercalation of fullerene derivative Phenyl-C60-butyric acid methyl ester (PCBM) into polyaniline (PANI) matrix with different ratio is reported. The PANI/PCBMx (where x = 0, 2.5, 5 and 10) nanocomposites are characterized by UV-VIS spectroscopy, Brunauer-Emmett-Teller (BET), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy and X-ray diffraction spectroscopy (XRD). The results confirm that the PANI/PCBM nanocomposites are synthesized successfully. The prepared nanocomposites are cast onto Nickel foam as a current collector and tested as a supercapacitor electrode in 2 M KOH electrolyte using cyclic voltammetry (CV) and galvanostatic charge-discharge (GCD). The effect of different current collector substrates including stainless steel, nickel metal and graphite sheet on the supercapacitor performance is compared. The electrochemical measurements show an improvement by more than two times in the specific capacitance of PANI/PCBM5 electrode compared to pure PANI electrode. It is found that, the specific capacitance is 2201 F/g at a current density of 2 A/g with a good rate capability of about 73% at 10 A/g. The energy and power densities of PANI/PCBM5 electrode are 61.9 W h/Kg and 2250 W/Kg, respectively. Furthermore, the PANI/PCBM5 electrode shows an excellent cycling stability with 96% of the capacity retention after 1000 cycles. (C) 2020 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.