SiOx as a Potential Anode Material for Li-Ion Batteries: Role of Carbon Coating, Doping, and Structural Modifications [chapter]

Hyeon-Woo Yang, Sun-Jae Kim
2018 Rechargeable Batteries - Recent Developments and Future Challenges from Material to Recycling Processes [Working Title]  
Despite the high energy density of SiO x , 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 SiO 2 , which leads to electrical contact loss and poor cyclability. Herein, we synthesized a C-SiO x composite based on amorphous carbon and a SiO x matrix via the alcoholysis reaction between SiCl 4 and ethylene glycol. We then used
more » ... polar 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-SiO x )@C composite with exceptional electrochemical properties. Next, we performed structural modifications using Ti doping and a multiple-carbon matrix to successfully fabricate a (C-Ti x Si 1− xO y )@C composite. The combination of Ti doping and carbon coating greatly enhanced the conductivity of SiO x ; moreover, the incorporated carbon acted as an effective oxide buffer, preventing structural degradation. The (C-Ti x Si 1− xO y )@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 .
doi:10.5772/intechopen.82379 fatcat:w22trc4txzceffgh33zrn3yfbm