A kind of lithium-sulfur battery and its diaphragm and preparation method of the diaphragm

Abstract

The invention discloses a lithium-sulfur battery, its diaphragm and a preparation method of the diaphragm, belonging to the technical field of lithium-ion battery diaphragms. A functional membrane for lithium-sulfur batteries of the present invention comprises a porous membrane substrate, the surface of which is provided with a functional structure layer, and the components of the functional structure layer include a filler, an adhesive, a lithium-conducting Ionic functional additives, wherein the filler is one or a combination of layered materials such as MoS2, graphene, iron sulfide, TiS2, ZrS2, and the addition amount is 15-80% of the total weight of the functional structural layer. A lithium-sulfur battery of the present invention adopts the above-mentioned functional film as a diaphragm. The technical solution of the invention can effectively suppress the "shuttle effect" of lithium polysulfide, and improve the coulombic efficiency, capacity and conductivity of the lithium-sulfur battery.

Description

technical field [0001] The invention belongs to the technical field of lithium-ion battery separators, and more specifically relates to a lithium-sulfur battery, a separator and a preparation method of the separator. Background technique [0002] In recent years, more and more new energy vehicles have appeared in people's daily life, and the state has also vigorously supported and promoted the marketization and application of new energy electric vehicles. Lithium-sulfur batteries use earth-rich and high-capacity sulfur as the positive electrode, and lithium as the negative electrode. During discharge, the negative electrode reacts as lithium loses electrons and becomes lithium ions, and the positive electrode reacts as sulfur reacts with lithium ions and electrons to form sulfide. The reaction equation It is: S8+16Li++16e-1=8Li2S. Due to the occurrence of multiple electron transfer reactions, lithium-sulfur batteries have a high theoretical specific capacity, and their theo...

AI Technical Summary

Problems solved by technology

The above two applications can suppress the "shuttle effect" of lithium polysulfide to a certain extent through the setting of functional sulfur-resistant coatings, but the effect still needs to be further improved

In addition, since the existing separator is usually prepared by the phase inversion method, its mechanical strength is low and the battery rate performance is poor.

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