| As a new kind of energy storage apparatus, double-layer capacitor (also called EC) developed very fast, and many new kinds of materials was tested nowadays. Carbon is a kind of electrode material, which is used widely now, and activated carbon and carbon nanotube are used often. Generally, activated carbon has a high resistance, and people add carbon black or carbon nanotube as additive to decrease resistance. Use carbon nanotube as electrode material, it is easy to prepare the electrode, but it is high in price. Carbon black has low resistance, so the electrode made of it has good conductivity, and the preparation of electrode is very easy, and carbon black is cheap. Acetylene Black is a kind of carbon black, so the preparation of electrode is easy too, and the production of Acetylene Black is very easy, and the price is low too. This paper tried to prepare EC with Acetylene Black, and tried to find the effect of different preparations to EC properties, the effect of different electrolytes to EC properties, and the effect of different circuit conditions to EC properties.This paper reviewed recent research works of EC, and summarized the main applications, materials, and productions of EC; and introduced the principles of double-layer capacitors. The Acetylene Black powder and the electrode microstructure were measured by both TEM and SEM respectively, and the charge-and-discharge curves were measured using a charge/discharge meter.Porous electric double-layer capacitors were prepared successfully with Acetylene Black and PTFE, where Acetylene Black was used as electrode precursor and PTFE as a binding. The capacitor has a specific capacitance of up to 7F/g, and it reached the highest specific capacitance that the Acetylene Black can support. This paper draw conclusions that:With the 30wt% NaOH solution as electrolyte, the specific capacitance of the double-layer capacitors increased with the decrease in preparation pressure of the electrode due to increasing both the proportion of the effective micro-pores and the available surface. As the preparation pressure decreased from 48Mpa to 16Mpa, 17% of the specific capacitance was increased. However, when the pressure was above 48Mpa, the capacitance had almost no change with decreasing preparation pressure because the pressure affected hardly on available surface. In addition, the charge density increased, hence the chargeable voltage increased with the increase in available surface because of high preparation pressure. The capacitor discharge slowly first and then speedily while the proportion of the micro-pores increased with increasing preparation pressure. Both the charge and the discharge behaviors of the double-layer capacitor were directly related to both the distribution and size of electrode poresMoreover, the specific capacitance increased with decreasing PTFE binding due to the increase in available surface. 46% of the specific capacitance was actively ascended as PTFE decreased from 14% to 6%.In addition, the charge density might increase and the chargeable voltage then increased with the increase in concentration of the NaOH solution. And specific capacitance didn't change because available surface didn't change when electrolyte concentration changed.When the electrolyte concentration was high enough (e.g. > 10wt%), the electrode structure of electrode didn't changed with different electrolyte, so the specific capacitance and the charge/discharge properties of capacitor didn't changed. When the electrolyte concentration waslow enough (e.g. pure water), the charge/discharge course was very fast, and the capacitance was very low.The ion drive force changed as the charge voltage changed, so the pore using conditions changed. As the charge voltage was raised, the number of pores in charge/discharge course increased, and the change of available surface increased, so the different with the capacitors whose available surface didn't changed was more serious. The increase of charge voltage affected capacitance through increasing the available surfa...
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