Carbon Encapsulated Silicon Nanoparticles As Anodes for Lithium Ion Batteries

Wednesday, 31 May 2017: 15:00
Grand Salon D - Section 24 (Hilton New Orleans Riverside)
P. Livan and T. Öztürk (Middle East Technical University)
Most recently, silicon anodes for lithium ion batteries have been extensively explored due to their large theoretical capacity, moderate operation potential, environmental friendliness and high abundance. However, poor capacity retention caused by the large volume change during intercalation process of lithium ions, its intrinsic low conductivity and the formation of insulating solid electrolyte interphase (SEI) films are limiting factors for applications of silicon anodes. The most common attempt is to combine the Si structure with a conducting carbonaceous layer, which possess excellent flexibility, high conductivity, light weight, electrochemical and thermal stability. In addition to the ability to accommodate the volume change and enhance electrical conductivity, encapsulation of Silicon nanoparticles in a protective and homogenous carbon coating prevent agglomeration and environmental oxidation. In this study, feasibility study of encapsulation process of Silicon nanoparticles was carried out with a arc discharge generator were the metal was made one at the electrode against graphite. Followed by this preliminary study, additional experiments were carried out with RF induction thermal plasma system where methane gas fed into the system in different feeding locations. The products were analyzed using different characterization techniques: XRD, SEM and HRTEM. Raman spectroscopy was used to analyze the quality of carbon shells. Efficient and scalable approaches were used to obtain carbon encapsulated Si nanostructures for use in lithium ion batteries. Also, utilization of comparative synthesis methods provide the direct observation of mechanism of encapsulation process and effects of the process parameters on the morphology and structure of encapsulates.