In Situ Catalyzed Growth of Carbon Nanotube with Asphalt Cladding as a Bicarbon Synergistic Framework of Silicon Anodes for Lithium-ion Batteries.

Abstract

Silicon, as the most promising advanced anode material for lithium-ion batteries, faces challenges in large-scale industrial production due to the significant volume expansion effect. In this investigation, Si/CNTs/C composite materials were effectively produced through high-temperature carbonization utilizing asphalt, silicon, hexahydrate ferric chloride, and melamine as primary elements. The distinctive dual-carbon framework of asphalt-derived carbon and carbon nanotubes alleviates the volume expansion of silicon, thereby stabilizing the composite material's structure. Testing the electrochemical performance reveals that the Si/CNTs/C composite material exhibits a reversible specific capacity of 1187 mAh g^-1 with a capacity retention rate of 92.6 % after 150 cycles at a current density of 0.2 A g^-1. Even after 500 cycles at a current density of 1 A g^-1, it sustains a specific capacity of 879.4 mAh g^-1 with a capacity retention rate of 87.9 %, showcasing outstanding electrochemical performance.