纳米级碳导电剂的种类对licoo2电化学性能的影响

碳纳米管;锂离子电池;正极;倍率容量;导电剂

Effects of Different Kinds of Nano-Carbon Conductive Additives on the Electrochemical Character of LiCoO2

After comparing the effects of three kinds of nano-carbon materials,namely,carbon nanotubes(CNTs),carbon black and chemical vapor deposit carbon fibers on the LiCoO_(2) cathode,the results indicate that the kind of nano-carbon conductive additives plays an important role in the electrochemical behavior of the cathode.Spherical carbon black prevent the formation of conductive network and therefore leads to a serious polarization.In contrast,wire-like conductive additives,especially CNTs,exhibit better electrontransfer ability,forms better conductive network in the cathode and hence alleviate the degree of cathode polarization owing to their high crystallinity,well ordered one-dimensional and cylindrical structure.Much amount of conductive additives and binder could be saved by utilizing CNTs, and the cathode with only 3% of conductive additive CNTs shows excellent rate capacity.At the discharge rate of 2.0C,the LiCoO_(2) cathode with CNTs still holds 95% of the discharge capacity shown at the discharge rate of 0.5C.