Design And Preparation Of Core-shell Stsructure C@V₂O₅ And Its Application In Lithium Sulfur Battery Positive Electrode

With the increasing demand for clean energy and sustainable energy,the development of energy storage technology has been promoted.Among the many energy storage technology applications,lithium-ion batteries with intercalated structures have been widely cited in portable electronic devices.However,typical rechargeable lithium ion batteries require a large amount of host compound?eg,CoO₂?to satisfy guest atoms?eg,Li?,which greatly limits their energy density to less than 210 Whkg^-1.The lithium-sulfur battery sulfur electrode has a theoretical specific capacity of up to 1672 mAhg^-1.When sulfur and lithium metal electrodes are combined,the energy density can reach 2654 Whkg^-1,which is3-5 times that of the existing lithium ion battery.In addition,sulfur is abundant and does not pollute the environment.This article will investigate the use of nanostructured metal oxides in lithium-sulfur batteries for better cycle life and higher performance.The relationship between the inherent properties of metal oxides and the performance of electrochemical performance in lithium-sulfur batteries is also discussed.In the synthesis of materials,a hydrothermal carbonization method was designed for the synthesis of uniform core-shell Te-carbon-rich composite nano-cable structures,with ultra-thin and ultra-long ruthenium nanowires as the core components,using glucose as the starting material.Carbon walls are grown outside the nanometer-diameter ultra-long tantalum nanowires.The results show that the presence of uniform Te nanowires can effectively inhibit the uniform nucleation of carbon spheres from bulk solution,and promote the heterogeneous deposition of carbonaceous materials on the main chain of ruthenium nanowires to form a uniform Te-carbon-rich composite.Nano cable structure.The diameter of the Te-carbon-rich composite nanostructure and the thickness of the coating can be controlled by controlling the amount of carbon source and the time of modification of the ruthenium nanofiber.After removing the ruthenium template in a simple manner,a tubular structure of functional carbonized carbon nanofibers with uniform structure and uniform dispersion can be obtained.In this paper,the carbon nanofibers with hollow structure were prepared as hard template,and the micro-nano structure of the carbon nanofiber@vanadium precursor with core-shell structure was successfully prepared by hydrothermal one-step method.The effect of oxygen on its morphology at different calcination rates and different calcination temperatures.The calcined carbon nanofiber@vanad pentoxide was used in the cathode material of lithium-sulfur battery to study its energy storage properties,and the initial specific capacity was 1000 mAh/g,and the stability was good after 100 cycles.The initial performance of lithium-sulfur battery prepared by pure carbon nanotubes is only500mAh/g,and the cycle stability is also poor.The feasibility of using vanadium metal oxide as the cathode material of lithium-sulfur battery to improve the performance of lithium-sulfur battery is verified.