Lithium-sulfur battery electrode and preparation method thereof, and lithium-sulfur battery structure containing lithium-sulfur battery electrode

Abstract

The invention discloses an electrode for a lithium-sulfur battery. According to the present invention, in-situ chemical deposition is performed on an electrode substrate to respectively deposit a metal nickel layer on both side surfaces of the electrode substrate, a metal nickel is deposited inside the electrode substrate, and the thickness of the metal nickel layer on the surface of the electrodeis 0.2-0.4 [mu]m; with the application of the electrode in the lithium-sulfur battery, the performance and the energy density of the lithium-sulfur battery can be significantly improved; and the chemical plating in-situ deposition technology has advantages of simple operation, mild experimental condition and low experimental cost, and has the great potential in the industrial large-scale production in the future.

Description

technical field [0001] The invention relates to the field of lithium-sulfur batteries, in particular to flexible electrodes of lithium-sulfur batteries. Background technique [0002] In recent years, with the increasingly serious global energy and environmental crisis, lithium-ion batteries have become the preferred power source for various electronic products such as laptop computers, electric bicycles and other electronic equipment. However, with the development of flexible electronics, people's demand for flexible and wearable media devices is increasing, such as OLED flexible smartphones, implantable devices, etc. These high-performance portable electronic devices need to have good mechanical flexibility In addition to performance, a high-performance battery with good flexibility is also required as a power output. Although lithium-ion batteries have the advantages of high working voltage and long cycle life, their relatively low energy density and poor mechanical prope...

AI Technical Summary

Problems solved by technology

These carbon materials used to load sulfur usually include porous carbon materials, carbon nanotube nanofiber materials, hollow carbon materials, graphene materials, and carbon materials composited with each other, but due to the non-polar characteristics of carbon materials themselves, it is difficult for many The adsorption of sulfide is weak, so the effect of slowing down the "shuttle effect" of polysulfide is not very obvious

[0005] Secondly, in the preparation of flexible electrodes for lithium-sulfur batteries, the electrode slurry usually includes active materials, binders, and conductive agents. In order to improve the flexibility and mechanical properties of the battery, the proportion of the binder will be greatly increased, so that the electrodes The conductivity drops

This makes the problems of discontinuous electron transport network inside the electrode and low utilization rate of active materials caused by the non-conductivity of active materials and discharge products that originally existed in lithium-sulfur batteries become more acute.

At the same time, in the process of preparing electrode materials, the prepared electrode slurry is usually coated on the metal film, and its thickness is usually about 25 μm. As a current collector, this layer of metal film not only occupies a certain electrode weight It can only be used as an inactive material, which reduces the volume and mass energy density, and the electrode material in flexible devices faces the problem of peeling off the active material from this film during battery bending, which affects battery performance.

The existing methods for preparing flexible electrodes mainly include using materials with light weight, good mechanical properties, and excellent electrical conductivity, such as graphene coatings, to replace metal films as current collectors, or by adding graphene and carbon to the electrode slurry. Conductive agents such as nanotubes are used to improve the conductivity inside the electrode, but the problems of these methods are firstly the high cost and complicated process, and secondly, adding conductive agents such as graphene or carbon nanotubes to the electrode slurry still cannot solve the problem due to adhesion. The discontinuity of the internal conductive network of the electrode caused by the addition of too high a proportion of the agent

Images