Abstract: In an attempt to develop small highpower supercapacitors a 1V-70F, 9cm3, coinshaped supercapacitor was fabricated using coconutshell activated carbon with a surface area of 1660m2/g and 6mol/L KOH as the electrolyte. The outer package was made from laminated aluminum foil covered with a nylon insulating layer. The electrochemical behavior was measured by constant current charge/discharge and electrochemical impedance spectroscopy. A specific capacitance of 79F/g was obtained. Results show that a specific power density of 170W/kg or 330 W/L, and a specific energy density of 1Wh/kg can be reached with an excellent discharge performance under high current density.