Preparation And Electrochemical Characterization Of Silicon/oxygen/carbon Composite Anode Materials For Lithium Ion Batteries

SiOx-based anodes have attracted tremendous attention owing to its higher theoretical capacity than graphite and smaller volume expansion than pure silicon. The most challenge of this material mainly is to relief the volume expansion and improve the coulombic efficiency and capacity retention. This is also the recent research hotspot. The SiO was adopted as a raw material to get SiOx particles through a facile high energy ball milling process. Using carbon nanofibers (CNFs)?graphite (C) and graphene aerogels (GA) to prepare SiOx/CNFs?SiOx/C and SiOx/GA composites. SEM?TEM?XRD?TG and electrochemical measurement was used to characterize the structure and electrochemical performance.By controlling the part process parameters are constant and changing the ball-milling time to explore the preparation technology of SiOx particles and to get the most superior electrochemical performance of SiOx particles.To prepare 1D carbon nanofibers by electrostatics spinning as one of carbon source. To prepare SiOx/CNFs composite by a two-step ball milling process. Optimizing the process to get a better SiOx/CNFs composite. The SiOx/CNFs electrode exhibits stable and high capacity of 417 mAh g-1 after 200 cycles at a current density of 0.1 A g-1 with capacity retention of 61.9%, which improve a little bit than SiOx electrode.Choosing the commercial 2D lamellar graphite as another carbon source.A facile two-step ball milling process was used to prepare the SiOx/C composite.Optimizing the materials proportion to get the better composite. The SiOx/C electrode exhibits stable and high capacity of 726 mAh g-1 after 500 cycles at a current density of 0.1 A g-1 with capacity retention of 82%.Choosing the 3D macroporous graphene aerogels as the other carbon source. Utilizing the self-assembly reaction of graphene aerogels to prepare SiOx/GA composite and explore the best preparation technology. The SiOx/GA electrode exhibits a stable and high capacity of 1130 mAh g-1 after 100 cycles at a current density of 0.1 A g-1, which shows the best electrochemical performance among the three composites.