Chapters authored
SiOx as a Potential Anode Material for Li-Ion Batteries: Role of Carbon Coating, Doping, and Structural Modifications
Despite the high energy density of SiOx, its practical use as an anode material for Li-ion batteries is hindered by its low electronic conductivity and sluggish electron transport kinetics. These disadvantageous properties result from the insulating nature of SiO2, which leads to electrical contact loss and poor cyclability. Herein, we synthesized a C-SiOx composite based on amorphous carbon and a SiOx matrix via the alcoholysis reaction between SiCl4 and ethylene glycol. We then used nonpolar benzene to simultaneously achieve homogenous dispersion of the Si source and the formation of a carbon coating layer, resulting in the formation of a (C-SiOx)@C composite with exceptional electrochemical properties. Next, we performed structural modifications using Ti doping and a multiple-carbon matrix to successfully fabricate a (C-TixSi1−xOy)@C composite. The combination of Ti doping and carbon coating greatly enhanced the conductivity of SiOx; moreover, the incorporated carbon acted as an effective oxide buffer, preventing structural degradation. The (C-TixSi1−xOy)@C composite exhibited excellent capacity retention of 88.9% over 600 cycles at 1 A g−1 with a capacity of 828 mAh g−1.
Part of the book: Energy Storage Devices