Preparation methods of super-capacitor carbons

Abstract

The invention discloses preparation methods of super-capacitor carbons. The preparation methods comprise the following steps: (1) corn is used as a raw material, pretreatment of degreasing and de-ashing is performed on the corn, and then moisture and low-temperature volatile components are removed through stepwise heating, so that a carbonized precursor is prepared; (2) a physical method and a chemical method are respectively used to perform respective activation on the precursor through high-temperature steam and strong alkali, so that porous activated carbons with different performance indicators are obtained; and (3) no impurity oxidation doping and molding are performed on the porous activated carbons, so that super-capacitor carbons with different performance indicators are obtained,wherein the super-capacitor carbon prepared through the physical method has a specific surface area of >=1800m<2>/g, a specific capacity of >=160F/g, a tap density of >=0.30g/cm<3>, an electrical resistivity of <=2.0[omega]m, a particle size distribution of D<50><=17[mu]m, and an ash content of <=0.2%; and the super-capacitor carbon prepared through the chemical method has a specific surface areaof >=1700m2/g; a specific capacity of >=260F/g, a tap density of >=0.30g/cm<3>, an electrical resistivity of <=2.0[omega]m, a particle size distribution of D<50><=17[mu]m, and an ash content of <=0.2%.

Description

technical field [0001] The invention relates to the field of electrochemical capacitors, in particular to a preparation method of supercapacitor carbon. Background technique [0002] Supercapacitors are also called electrochemical capacitors. Under normal circumstances, their large specific capacitance, good cycle stability, simple working principle, high power density, and fast charging and discharging speed have gradually become the focus of people's attention. At the same time, it is also related to the two The combination of secondary batteries can realize the complementarity of specific energy and specific power, so it can be applied in the fields of electric vehicle power supply and power engineering. [0003] At present, there are three main types of materials used for polarizing electrodes of supercapacitors, namely carbon materials, metal oxide materials and conductive polymer materials. The common carbon material is activated carbon. Because of its high specific s...

AI Technical Summary

Problems solved by technology

However, the general activated carbon electrode material is derived from coal and woody raw materials, with high ash content, low conductivity, poor cycle performance, and rapid decay of specific capacitance under high-rate charge-discharge conditions, which is difficult to meet the needs of supercapacitors.

Other materials such as graphene, carbon nanotubes, etc. are constrained by cost and technology, and the commercialization progress is slow. The real practical problems of low cost, large capacity, and fast charging and discharging have not yet been solved.

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