Nano-porous Si/C composites for anode material of lithium-ion batteries

Nano-porous silicon composite incorporated with graphite and pyrolyzed carbon was synthesized and investigated as a promising anode material for lithium-ion batteries. The nano-porous Si/graphite composite was prepared via two-step ball-milling followed by etching process. Then carbon was incorporated by using different approaches. The nano-porous Si/graphite/C composite exhibits a reversible capacity of about 700 mAh/g with no capacity loss up to the 120th cycle at a constant current density of 0.2 mA/cm². The superior electrochemical characteristics are attributed to the nanosized pores in Si particles, which suppress the volume effect, and buffering action as well as excellent electronic and ionic conductivity of carbon materials.