Carbon black and vapor grown carbon fibers binary conductive additive for the Li1.18Co0.15Ni0.15Mn0.52O2 electrodes for Li-ion batteries

•CB/VGCFs binary conductive additive is used for Li-excess layered cathode electrode.•The binary conductive additive constructs a continuous network for electron transport.•The binary conductive additive improves the electrochemical kinetics of the electrode.•Improved electrochemical performance is gained using the binary conductive additive.

Carbon black (CB) and vapor-grown carbon fibers (VGCFs) are used as conductive additives for the Li1.18Co0.15Ni0.15Mn0.52O2 electrodes for Li-ion batteries. The fibrous VGCFs can bridge the isolated Li1.18Ni0.15Co0.15Mn0.52O2 regions, thus construct an effective conductive network for electron transport. In addition, incorporation of CB and VGCFs can improve the electrochemical kinetics of the cathode material by retarding the harmful side reactions, promoting the charge transfer reactions and increasing the apparent lithium diffusion coefficient. In all electrodes under investigation, the one prepared with 3 wt.% of VGCFs and 12 wt.% of CB shows the largest discharge capacity of 252 mAh g−1 at the 0.2C rate with excellent capacity retention and rate capability.