Influence of induction-annealing temperature on the morphology of barley-straw-derived Si@C and SiC@graphite for potential application in Li-ion batteries

摘要

Silicon, a material with high theoretical energy density, holds great promise as a candidate material for anodes in lithium-ion batteries. However, due to an alloying mechanism the material undergoes volume expansion of up to 300%, which results in rapid capacity fading. The coating of silicon with carbon is done by using a biomass-based carbon precursor. The effects of annealing temperature on the morphology of the silicon-carbon structures is presented herein. The mechanically and chemically treated barley straw is mixed with silicon particles and induction annealed in argon atmosphere under different temperatures. The material transformation from carbon-coated silicon (Si@C) to graphite-coated silicon carbide (SiC@graphite) is studied. The Si@C displayed initial specific capacity of 1200 mAh g(-1) at 0.1 A g(-1), while the capacity retention analysis of Si@C revealed improved cycling stability compared to bare silicon.