Lithium-sulfur battery diaphragm

Abstract

The invention relates to a lithium-sulfur battery diaphragm. The lithium-sulfur battery diaphragm comprises a base diaphragm and a functional layer, the functional layer is arranged on the surface ofthe base diaphragm, wherein the functional layer comprises multiple MoP2 nano-particles and multiple graphene sheets, the MoP2 nano-particles and the graphene sheets are mixed with one another and uniformly distributed, the graphene sheets are in lap joint with one another or arranged stackedly to form a whole graphene layer, the MoP2 nano-particles adhere to the surfaces of the graphene sheets, and when the lithium-sulfur battery diaphragm is applied to the lithium-sulfur battery, the functional layer directly faces the cathode of the lithium-sulfur battery.

Description

technical field [0001] The invention relates to a lithium-sulfur battery diaphragm. Background technique [0002] Lithium-sulfur batteries use sulfur as the cathode and metallic lithium as the anode. During discharge, the anode reaction is that lithium loses electrons to become lithium ions, and the cathode reaction is that sulfur reacts with lithium ions and electrons to form sulfide. Due to the occurrence of multiple electron transfer reactions, it has a very high theoretical specific capacity, with a specific capacity as high as 1672mAh / g (milliamp hour / gram). In addition, because sulfur has the characteristics of less environmental pollution, non-toxicity, low cost, and wide source of raw materials, lithium-sulfur batteries have received more and more attention. [0003] Separators are an important component in lithium-sulfur batteries, separating the cathode and anode to avoid internal short circuits while facilitating the transport of free lithium ions between the el...

AI Technical Summary

Problems solved by technology

Parasitic reactions caused by polysulfide dissolution seriously affect the cycle performance and Coulombic efficiency of Li-S batteries

However, it is difficult for the existing lithium-sulfur battery separators to inhibit the diffusion of polysulfides, which in turn allows polysulfides to shuttle between the cathode and anode, resulting in irreversible destruction of the sulfur-containing structure of the cathode.

The shortcomings of the above-mentioned separators lead to a series of problems such as poor cycle stability and low actual specific capacity of lithium-sulfur batteries.

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