Patent ID: 11361909

Abstract:
Disclosed are an ultra-low temperature and high-capacity supercapacitor and a preparation method thereof. The electrode material used in the ultra-low temperature and high capacity supercapacitor is a composite porous carbon material comprising micropores and mesopores, the specific surface area of the electrode material is greater than 2500 m2/g, the pore size of micropores is larger than 0.8 nm, the pore size of mesopores is 2-3.0 nm, and the proportion of micropores is greater than 70%. The electrolyte of the supercapacitor is a solution of spirocyclic quaternary ammonium tetrafluoroborate in a mixed solvent of 1,3-dioxolane (or methyl formate, or a mixture of both)/acetonitrile. Based on the above electrode materials and combined with the above electrolyte, the supercapacitors as prepared can have a mass specific capacitance of greater than 150 F/g and a volume specific capacitance of greater than 80 F/cm3, under a temperature of −100° C. and at a current density of greater than 1 A/g.