Improving the performance of Li-ion battery carbon anodes by in-situ immobilization of SiOx nanoparticles

Abstract

A 30% improvement of the capacity of a lithium ion battery was demonstrated by introducing a C/SiOx nanocomposite electrode having a SiOx nanoparticle loading of 15 wt.%. The nanocomposite was tailored from tetraethyl orthosilicate (TEOS) and 3-aminophenol which simultaneously underwent hydrolysis-condensation and polymerization, respectively, to produce a C/SiO2 intermediate when subjected to microwave irradiation. SiO2 was present as nanoparticles on the carbon surface, which allowed for facile reduction. Under a mild reducing agent, concurrent carbonization of the 3-aminophenol polymer and the reduction of SiO2 nanoparticles were performed. The value of x in the synthesized C/SiOx was 1.24 according to the binding energy from the Si 2p x-ray photoelectron spectroscopy spectrum. The synthesized C/SiOx nanocomposite delivered a reversible capacity of 383 mA h/g as a lithium battery anode—a 30% improvement on the carbon-only electrode. Charge-discharge cycling shows 84% capacity retention after 100 cycles.