Pitch modified hard carbons as negative materials for lithium-ion batteries

A series of pitch modified hard carbons was prepared using coal-tar pitch and phenolic resin as carbon precursors. The effects of the amount of the soft carbon from pitch precursor, varying from 0 wt% to 40 wt%, and heat-treatment temperature in the range from 900 °C to 1800 °C, on their electrochemical performance were systemically studied, including the reversible capacity, coulombic efficiency in the first cycle, the rate capability and cycling stability. Under the optimal condition, the carbon material obtained at 1200 °C with 30 wt% soft carbon as negative material for lithium-ion batteries exhibits a reversible capacity of about 290 mAh g−1 at a constant current density of 0.5 mA cm−2 with excellent rate capability and cycling stability.