Preparation method of nitrogen-rich multimode beehive carbon-sulfur composite anode material

Abstract

The invention relates to a preparation method of a lithium sulphur battery composite anode material. The preparation method is as follows: preparing a mixed solution of carbon tetrachloride, a nitrogen source and carbonate, heating and flowing back to obtain a nitrogen-rich polymerization / carbonic acid salt compound; high temperature pyrolyzing in a nitrogen or argon atmosphere after drying the compound, so as to form the nitrogen-rich carbon / oxide compound; adding dilute acid to remove vestigial oxide, so as to form the nitrogen-rich multimode beehive carbon material of a multilevel porthole structure; uniformly mixing the nitrogen-rich multimode beehive carbon and sublimed sulfur, heat preserving under vacuum condition, injecting sulfur gas to the nitrogen-rich multimode beehive carbon material, so that the lithium sulphur battery composite positive material can be obtained. The composite anode material provided by the invention is alveolate, and has the advantages that portholes are abundant, sulfur content is high, sulfur particle can be distributed uniformly in the nitrogen-rich multimode beehive carbon material of the multilevel porthole structure, and the carbon sulfur particles can be combined more tightly, the material mechanical stability is high, discharge specific capacity is high, cycle performance is excellent, and technological process is simple, pollution is avoided, cost is low, and the method is liable to large scale production and application.

Description

technical field [0001] The invention relates to a preparation method of a lithium-sulfur battery positive electrode material, in particular to a preparation method of a nitrogen-rich multi-mode honeycomb carbon-sulfur composite positive electrode material. Background technique [0002] With the popularization of portable electronic products, the rapid development of energy storage technology and electric vehicles, the requirements for the energy density and power density of lithium-ion batteries are getting higher and higher. It is predicted that the future 4G mobile communication requires the energy density of the battery to reach more than 500Wh / Kg. Lithium-sulfur batteries have high specific capacity (1675mAh / g) and high energy density (2600Wh / kg). The positive electrode material is rich in elemental sulfur resources, low in price, and environmentally friendly. Therefore, lithium-sulfur batteries are high-energy-density secondary batteries with great development potentia...

AI Technical Summary

Problems solved by technology

However, due to the limitation of many factors such as the conductivity of the carbon carrier, specific surface area, pore size distribution, and pore volume in the above-mentioned composite materials, the sulfur content in the carbon-sulfur composite material is not high, generally not higher than 70%, making lithium The overall capacity of sulfur batteries decreases, making it difficult to realize industrial production

[0005] China Patent Network CN 101891930A discloses a method for preparing carbon nanotube sulfur-based composite cathode materials by heat treatment. This method is beneficial to the dispersion of carbon nanotubes and the uniform distribution of sulfur, but due to the high viscosity of molten sulfur during heat treatment, Difficult to fully immerse into the pore structure of carbon materials, low sulfur content in composites and difficult to control

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