Abstract: The supercapacitor has a wide range of applications.However,the traditional activated carbon can't fully meet the needs of the society in terms of energy density and electrical conductivity,which severely limits its application in large-scale energy storage devices.Therefore,it is of great significance to develop materials with higher energy storage performance.In this paper,a new coal-based microcrystalline carbon was prepared by preliminary carbonization coupled with KOH as activator process with abundant Taixi anthracite and used as electrode material for supercapacitor.The microstructure and pore structure parameter of the coal-based microcrystalline carbon was characterized by the methods of X-ray diffraction and low temperature N_2adsorption-desorption.The electrochemical performances of the corresponding electrode material were also investigated using galvanostatic charge/discharge,cyclic voltammetry and ac impedance.The results show that the coal-based microcrystalline carbon contains a large number of relatively complete graphite-like microcrystalline structure,and with the increase of alkali/carbon ratio,the graphite-like microcrystalline structure is gradually destroyed,and its layer spacing d_(002)gradually increases from 0.391 5 nm to 0.405 9 nm.The microcrystalline carbon with a specific surface area of 928 m~2/g,total pore volume of 0.527 cm~3/g and mesoporosity of 26.46%can be prepared at 800℃for 2 hours under the alkali/carbon ratio 4.The coal-based microcrystalline carbon applied as electrode materials for supercapacitor exhibits an excellent electrochemical performance in(C_2H_5)_4NBF_4/PC electrolyte.The specific capacitance of microcrystalline carbon is 94.8 F/g at a current density of 50 m A/g and the energy density reaches to 40.3 Wh/kg and at a current density of 500 m A/g,the initial specific capacitance is retained 87.3%after 1 000 cycles.It has good cycle stability and also shows smaller ionic diffusion resistance and internal impedance in the impedance curve.In the first charging process,the bend on charging curve means that the"electrical activation"phenomenon occurs.During this time,the electrolyte ions and solvent molecules around the microcrystalline carbon layerintercalate,making full use of the wafer space to store electrons to improve the energy density.The capacitance characteristics of coal-based microcrystalline carbon are mainly composed of intercalation capacitance and double-layer capacitance,among which intercalation capacitance caused by"electrical activation"is the main reason for the higher energy density of microcrystalline carbon.The superior electrochemical performance of the new coal-based microcrystalline carbons is strongly related to the microcrystalline structure and abundant pore structure.