Preparation and application of anode carbon-based membrane material for lithium-sulfur battery

Abstract

The invention discloses a preparation method and application of a positive electrode carbon-based membrane material for a lithium-sulfur battery. According to the carbon-based membrane material provided by the invention, a polyacrylonitrile / carbon nanotube / MXene mixed solution is subjected to solvent phase conversion and carbonization to form a porous carbon-based membrane material, and the porous carbon-based membrane material is applied to a lithium-sulfur battery through sulfur loading. The carbon nanotubes are added into the membrane material, so that the whole membrane is of a porous structure, and the conductivity of the membrane material is improved; MXene added into the membrane is beneficial to providing chemical adsorption and catalytic conversion for polysulfide, the shuttle effect of the lithium-sulfur battery can be effectively inhibited, and meanwhile, the relatively high conductivity of the membrane further promotes ion transmission, so that the cycling stability and coulombic efficiency of the battery are improved. The lithium-sulfur battery prepared from the carbon-based membrane electrode has good electrochemical performance, the specific capacity is 859.4 mA h g<-1> after 100 cycles under the current density of 0.2 C, the capacity loss rate of each cycle is 0.23%, and the coulombic efficiency is close to 100%.

Description

technical field [0001] The present invention relates to the field of cathode materials for lithium-sulfur batteries, and relates to the preparation and application of anode carbon-based film materials for lithium-sulfur batteries, in particular to a cathode carbon for lithium-sulfur batteries constructed of polyacrylonitrile / carbon nanotube / MXene composite materials Preparation method and application of base film material. Background technique [0002] Nowadays, in order to solve the contradiction between the world's growing demand for fossil fuels and gradually strict greenhouse gas emissions, the development and utilization of new energy sources is of great significance. Among them, renewable new energy sources such as wind energy, tidal energy, and solar energy are due to their The instability of output power is difficult to meet people's production needs. Therefore, the development of high-performance energy storage devices such as batteries to store and reuse unstable ...

AI Technical Summary

Problems solved by technology

However, at present, there are still problems such as low sulfur loading capacity, low conductivity of elemental sulfur, and "shuttle effect" on the positive side of lithium-sulfur batteries, especially the existence of the shuttle effect, which leads to a large loss of battery active materials, rapid capacity decay, and unsatisfactory cycle life. , restricting the practical application of lithium-sulfur batteries

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