Enhancing the rate and cycle performance of graphite anode for Li-ion batteries by constructing a multidimensional conducting network

Conductive carbon additives play very important roles on the performance of Li-ion batteries (LIBs) although they only occupy a very small mass percentage in both cathode and anode. Building up a multidimensional carbonaceous conductive network on cathode with the optimized mass ratio of carbon black, carbon nanotubes (CNTs) and graphene has been verified to be able to enhance the Li-ion storage performance. Herein, we further demonstrate that applying ternary conductive additives is also very effective in improving the rate and cycle performances of graphite anode although the active material already possess high electronic conductivity. A conductive additive assembly of 2 wt% Super P, 1 wt% CNTs and 1 wt% graphene can weave up an efficient conducting pathway on the mesocarbon microbeads (MCMB) anode and enhance the cycle stability (344 mAh g−1 at 1 C after 200 cycles) and rate performance (226 mAh g−1 at 3 C). The coin-type full cell assembled with the optimized MCMB anode and NCM811 cathode also displays much improved rate capability and cycle stability. As is revealed, the multidimensional conducting network might has led to a more uniform and ion conductive SEI film on MCMB anode, which lowers the polarization and energy barrier for Li+ transportation.