Self-supporting porous carbon used for supercapacitor electrode material and preparing method thereof

Abstract

The invention discloses self-supporting porous carbon used for a supercapacitor electrode material and a preparing method thereof. The self-supporting porous carbon is of a three-dimensionally-communicated large-pore structure, the aperture of large pores is 5-20 microns, the wall thickness is 80-200 nm, mesoporous structures and micropore structures are formed on the hole walls, the specific area can be 1,000 m<2> / g or above, and the density is lower than 10 mg / cm<3>. Meanwhile, the invention discloses a preparing method of the self-supporting porous carbon. The self-supporting porous carbon has the advantages that the self-supporting porous carbon has multi-stage pore structures including the large-pore structure, the mesoporous structures and the micropore structures, the specific area can be 1,000 m<2> / g or above, the specific capacitance can be 246.5 F / g, the charging-discharging current density is increased to 10 A / g from 0.5 A / g, the specific capacitance retention rate is 80% or above and 95% or above after 10,000 times of circulation, and the power density of an assembled symmetric capacitor can be 25 Kw / kg.

Description

technical field [0001] The invention belongs to the field of electrode materials, and in particular relates to a self-supporting porous carbon used for supercapacitor electrode materials and a preparation method thereof. Background technique [0002] Supercapacitor is a new type of electrochemical energy storage device, which has many advantages such as high power density, long cycle life, high charge and discharge efficiency, and environmental protection. Supercapacitors have a wide range of uses and can be widely used in new energy vehicles, new energy power generation, construction machinery, rail transit, lifting equipment, and military equipment. [0003] As an important part of supercapacitors, electrode materials are the key to determining the performance of supercapacitors. Carbon materials have the advantages of high specific surface area, good electrical conductivity, stable chemical properties, low cost, and abundant sources, and are widely used in the preparatio...

AI Technical Summary

Problems solved by technology

At present, although porous carbon materials prepared with chitosan as a carbon source have been reported, the prepared carbon materials are all powder materials, and the preparation method of the powder materials is usually divided into two steps: one is to prepare chitosan powder Pre-carbonization at a certain temperature; the second is to mix the pre-carbonized product with an activator and then activate it at a high temperature to obtain activated carbon, but this preparation method has the following problems: (1) The prepared carbon material is in powder form and cannot be directly used as a super carbon material. For the use of capacitor electrodes, a binder needs to be added when preparing the electrodes and coated on the current collector for use; (2) The preparation process generally has two steps, pre-carbonization and activation, both of which are carried out at high temperature, and the preparation process is relatively cumbersome; (3) In the activation stage, because the pre-carbonized product and the activator are mixed in a solid state, or the pre-carbonized product is soaked in a certain concentration of activator solution and then dried, it may cause uneven distribution of the activator in the pre-activated carbon. uniform, making it difficult to control the properties of the final product

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