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Electrochemical capacitor (EC) to quickly charge and discharge but also a long life, is considered to be between a secondary battery and a capacitor between the new energy device. Its large capacity, low leakage current, voltage memory, charge and discharge cycles. The electrode material is one of the main factors determining the performance of electrochemical capacitors. Carbon electrode due to its high electrical conductivity, surface area distribution of a wide range, proliferation of small internal resistance, high temperature stability, pore structure is easy to control, good the composite and compatibility with other materials, low cost, is an excellent electrochemical capacitor electrode material. This article first discusses the possibility of needle coke as raw materials, carbonization - activated prepared by electrochemical capacitors activated carbon electrode material, carbonization temperature of activated carbon structure and behavior of the capacitors. After carbonization of the first 700 ° C 700 ° C activation resulting needle coke-based activated carbon (AC7) specific surface area of ??553.2m2 / g, with its assembled organic electrochemical capacitor having a relatively high capacity and good cycle performance. AC7 quality than the capacitance from 50mA / G 150.2F / g decay to 200mA / G 136.0F / g, attenuated only 9.45%, showing a good capacitance characteristics and rate characteristics, at the same time from the AC impedance test AC7 the internal resistance of the prepared material is also the smallest. Prepared by direct activation electrochemical capacitors needle coke based activated carbon electrode materials, activator properties of activated carbon prepared. Such as the use of NaOH for the activator NAC7 the ratio surface area of ??869.73m2 / g, porosity 32.56%, while KOH the activator KAC7 specific surface area of ??1570.39m2 / g, porosity of 10.42%. Two activated carbon electrode material prepared organic electrochemical capacitors, NAC7 capacitance characteristics better than KAC7. NAC7 good cycle performance, the density of the type of charging and discharging, the capacity change compared KAC7 small. In addition, according the experimental NAC7 800mA / g current density cycle 5000 times, the capacity is only reduced by 9.1%. Will direct activation method the product NAC7 and the product of KAC7 carbonization - activation method AC7 comparison, cyclic voltammetry, AC impedance and constant current charge and discharge contrast, found that the performance of NAC7 most superior AC7 cyclic voltammetry The Ann curve, AC impedance is stronger than KAC7 or less constant current charge-discharge tests KAC7.
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