Preparation, Characterization&Lithium Storage Research Of Silicon/Carbon Composites

Since the Gulf War and the Kosovo War in the1990s, many countries haveincreased the competition for energy development and use. This also brings a lot ofenergy crisis and environmental pollution, so scientists are try their best to find new,green and recyclable energy. Since the first successful production of Sony for itslithium-ion battery, it has been widely used in mobile phones, laptops and other portabledevices due to its high energy, long life, rated voltage, high power with high endurance aswell as environmental friendly, etc. In addition, the lithium-ion battery has been used inthe electric vehicles trial, and is expected to become one of the major driving for futureelectric vehicles. In the lithium-ion battery, the anode material is one of the key factorsthat determine its performance, because of the silicon has a maximum theoretical capacity,abundance in nature, and environmental friendly, which is widely popular among theresearch workers. Meanwhile, the carbon has a good cycling stability and electricalconductivity, which also draw the researchers’ attention. This article is focus on thepreparation, characterization and lithium storage performance research of silicon/carbonnanocomposites, exploring its prospects in energy conversion and storage. The maincontents are as follows:Preparing for Si NWs@C composites based on nickel foam, first, using thesingle-crystal Si as deposit, and chemical etching method producing high-quality singlecrystal silicon nanowires arrays. Then let the nickel foam immerse into the Si nanowiressolution to obtain three-dimensional structure of Si nanowires based on nickel foam.Finally, immersing it into the glucose solution and carbonization, and Si NWs@C will beobtained. The obtained Si NWs@C composites were characterized by SEM, TEM,Raman and lithium storage performance. The results show that the Si NWs@Ccomposites based on nickel foam display a good cycling stability, and much moreexcellence than pure Si nanowires anode material for lithium storage.Preparing for Si NPs@C by electrospinning, first, the Si nanoparticles and PANdissolved in DMF uniformly, and producing Si NPs@PAN by electrospinning, and SiNPs@C obtained after annealing. Since C has good flexibility, so that the complex SiNPs@C forms a complete sheet-like structure. The crystalline C has good electricalconductivity, enhancing the conductivity of the anode material, accelerating the transportof electrons, besides, due to its flexibility, it can buffer volume expansion of the Sinanoparticles during charge and discharge. Meanwhile, the integrity of the sheet-likestructure, the non-conductive adhesive has been avoided into the anode material,increasing energy density. The Si NPs@C results an excellence electrochemicalperformance.