| Supercapacitors are new energy storage devices with intermediate performance between batteries and dielectric capacitors, which have high power density, longe cyclic life and short charge/discharge capability, etc. They have multiple applications including automobiles, UPS, aeronautics and astronautics, military, etc. Electrode materials play a crucial role in supercapacitors. In this paper, activated carbons with high surface area were prepared from polyvinylidene chloride and phenolic resin by steam activation, and their capacitive performances were investigated in detail. The specific surface area and pore structure were characterized by N2 absorption/desorption isotherms. Their electrochemical performances in 6 mol.L-1 KOH aqueous electrolyte and 1 mol.L-1 Et4NBF4/PC electrolyte were evaluated by galvanostatic charge-discharge, cyclic voltammetry and impedance spectroscopy.PVDC-based activated carbon prepared at 880℃for 1h has surface area as high as 2290 m2.g-1 with mesoporosity ratio of 39.5%. Its capacitance in aqueous electrolyte reaches 177 F/g with good rate performance. The sample prepared at 880℃for 1h has the highest capacitance of 122 F/g in non-aqueous electrolyte.The optimal preparation conditions of the phenolic resin-based activated carbon are found at carbonization time and temperature of 1h and 900℃, activation time and temperature of 1h and 850℃. Its capacitance in aqueous and non-aqueous electrolyte can reach 162 F/g and 107 F/g respectively. the relative capacitance (C2/C50) is 78.4% and 53.3% . The capacitance is stabilized at higher current densities.The electrochemical properties of a series of porous carbons prepared from phenolic resin by catalytic activation were discussed. Porous carbon is prepared at 850℃for 1h when the catalyzer amount is 1% of zirconium(IV) acetylacetonate. Its capacitance in aqueous and non-aqueous electrolyte can reach 160 F/g and 103 F/g .
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