Electrode characteristics of pitch-based carbon fiber as an anode in lithium rechargeable battery

The relations between the electrode characteristics and structures or textu res of pitch-based carbon fibers controlled by spinning or stabilization co nditions were investigated, The graphitized fiber spun at a lower viscosity , had a higher degree of graphitization and a higher discharge capacity. Th e graphitized fiber spun at a higher viscosity, exhibited a higher rate cap ability, suggesting that lithium ions can diffuse more easily in a fiber co mposing of smaller crystallites than larger ones. The graphitized fiber sta bilized at a higher temperature, showed a lower irreversible capacity, whic h may be due to the relatively less developed graphite structure in the sur face region. The graphitized pitch-based carbon fiber prepared with optimum conditions achieved a maximum discharge capacity of 315 mAh/g, an initial irreversible capacity of 10 mAh/g and an initial coulumbic efficiency of ab out 97%. (C) 1999 Elsevier Science Ltd, All rights reserved.