Preparation method of diaphragm material of lithium-sulfur battery

Abstract

The invention relates to a diaphragm material of a lithium-sulfur battery, in particular to a metal organic framework material and a preparation method thereof. The preparation method comprises the following steps of S1, preparing a ZIF-8 (zeolite imidazolate framework-8) nanopowder; S2, preparing ZIF8 / CNT (carbon nanotube) composite fiber wires by electrostatic spinning; S3, carbonizing, so as toobtain the hollow porous ZIF8@CNTs; mixing the hollow porous ZIF8@CNTs, conductive carbon black and PVDF in a NMP solution, grinding, applying onto a clean diaphragm, and drying, so as to obtain themodified diaphragm of the lithium-sulfur battery. The diaphragm material has the advantages that the property of the diaphragm material is improved; the defects of obvious shuttle effect of polysulfides in the lithium-sulfur battery prepared by the prior art, obvious volume expansion effect of the lithium-sulfur battery, instability in the electrochemical property of the battery and the like are overcome; the production technology is simplified, and the production cost is reduced.

Description

technical field [0001] The invention relates to a preparation method of a diaphragm material for a lithium-sulfur battery, and more particularly relates to a preparation method of a metal-organic framework material as a diaphragm material, belonging to the field of material chemistry. Background technique [0002] With the progress and development of social productivity, energy has become one of the key factors affecting social development. Due to the non-renewability of traditional fossil fuels (coal, petroleum) and their unfriendliness to the environment (such as the greenhouse effect, acid rain, etc.), it is imminent to develop a renewable green energy system. At present, new green energy systems such as wind energy, solar energy, and tidal energy have been widely used, partially alleviating the human energy crisis. The application of the above-mentioned new green energy system inevitably involves the issue of energy storage, that is, a large-capacity and more flexible a...

AI Technical Summary

Problems solved by technology

The shuttle effect reduces the utilization of sulfur electrode active materials

At the same time due to Li 2 S and Li 2 S 2 It cannot be dissolved in the electrolyte and deposited on the surface of the anode, which further reduces the performance of the lithium-sulfur battery

Due to sulfur and the final product Li 2 The density of S is different, and the sulfur cathode will undergo a large volume change before and after the electrode reaction, so the electrode is easily pulverized during multiple cycles, resulting in damage to the battery

[0004] In order to solve the appeal problem, it has been proved that the modification of the diaphragm of the battery can significantly inhibit the shuttle effect of polysulfides and play a role in capturing polysulfides. Although the existing technology has improved the performance of lithium-sulfur batteries to a certain extent performance, but the common disadvantages are: the electrochemical performance of the battery is unstable, the specific capacity is not high enough, the shuttle effect of polysulfide is still obvious, the volume expansion of lithium-sulfur ion battery is significant, the experiment is more complicated, the operation is difficult, and the production cost high

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