Effect Of Different Conductive Agents Used On The Performance Of Supercapacitors

The super-capacitor is a novel storage device between the rechargeable battery and traditional static capacitor, with the advantages of high power density, high energy density, long cycling life, wider work temperatures, better voltage memory and free of service, and thus has been applied more and more widely in many fields. The performance of super capacitors highly depends on the electrode materials. Owing to its low cost, good formability, high electrochemical stability and technical maturity, activated carbon was the earliest electrode material and has been paid great attention to.In this paper, two kinds of activated carbon, YK1 and YP17, were used as electrode materials and three conductive agents were added in different proportions. Electric double layer capacitors (EDLC) of aqueous and organic system were assembled according to certain process. The effect of the variety and proportion of conductive agents on the electrochemical performance of the EDLC was investigated systematically by charge/discharge measurement, cyclic voltammetry and electrochemical impedance spectroscopy measurement. The results indicate that:1. If activated carbon YK1 was used as the electrode material in the aqueous capacitor: When Vxc-72 was chosen as the conductive agent, the model EDLC showed the highest specific capacitance of 245.1F/g at the current of 50mA/g; When micro-powder graphite was used as conductive agent and its proportion added was 10%, the model EDLC showed the highest specific capacitance of 232.5F/g at the current of 50mA/g. The capacitors with the two kinds of conductive agents added both showed good rate characteristics; and the results of electrochemical tests indicate the capacitors with different conductive agents both show good electrochemical performance.2. If activated carbon YP17 was chosen as electrode material and VGCF, Vxc-72 and micro-powder graphite as conductive agents respectively in organic system, the model EDLC with micro-powder graphite used as the conductive agent showed the best capacitance and rate characteristics. And the result was the most desirable.