Nitrogen-containing carbons prepared from polyaniline as anode materials for lithium secondary batteries

Nitrogen-containing carbons have been prepared from polyaniline by carbonization and activation. Lithium storage performances of the carbons have been studied by galvanostatic charge/discharge. The carbon without activation shows a first discharge capacity of 729 mAh g^− 1, after activation, the capacity improved. The first discharge capacity of the carbon prepared by H₃PO₄ activation is 1083 mAh g^− 1, and that of the carbon prepared by KOH activation is as high as 2201 mAh g^− 1, whose reversible capacity is 1027 mAh g^− 1. To the carbon prepared by KOH activation, the first coulombic efficiency is just 47%, however, from the second cycle, the coulombic efficiency goes up rapidly to above 90%, the reversible capacity is still as high as 747 mAh g^− 1 after 20 cycles. It may be a promising candidate as an anode material for lithium secondary batteries.