Composite diaphragm for lithium-sulfur battery and preparation and application thereof

Abstract

The invention discloses a composite diaphragm with an ultrathin coating and a preparation method and application thereof. A layer of interface film is generated through polymerization reaction of twomonomers on an oil-water interface, and then the interface film is transferred to a porous polyolefin diaphragm to form the composite diaphragm. The thickness and the surface aperture of the interfacefilm can be effectively controlled, and the formed composite diaphragm can effectively inhibit the shuttle flying effect of polysulfide and has higher mechanical strength; in addition, the method issimple in preparation process, low in time consumption, low in cost and beneficial to further popularization and application.

Description

technical field [0001] The invention relates to the field of lithium-sulfur batteries, in particular to a composite diaphragm and its preparation method and application. Background technique [0002] In order to solve the energy crisis and the environmental pollution caused by the combustion of fossil fuels, electric vehicles have received more and more attention. At present, lithium-ion batteries with lithium iron phosphate and ternary materials as positive electrodes are widely used in electric vehicles. Due to the limitation of material properties, lithium-ion batteries have a theoretical specific capacity of 300mAh / g, which cannot meet the needs of long-range electric vehicles. The theoretical specific capacity of lithium-sulfur batteries is five times that of commercial lithium-ion batteries (theoretical specific capacity is 1672mAh / g, specific energy is 2600Wh / kg). It is considered to be one of the most potential high-energy batteries. [0003] However, the real comm...

AI Technical Summary

Problems solved by technology

[0006] Purpose of the invention: the main purpose of the invention is to solve the

Images