Neuron like Si-carbon nanotubes composite as a high-rate anode of lithium ion batteries

An in-situ formed neuron-like Si-CNT composite is realized with a modified chemical vapor deposition method, in which Ni(CH3COO)2 and quinolinic acid serve as catalyst and the carbon source, respectively. Under Ar/H2 gas-flow at 900 °C, Ni(CH3COO)2 is reduced to nickel nanoparticles and quinolinic acid is decomposed into carbon fragments. Under the catalysis of the nickel nanoparticles, carbon nanotubes are generated in between the silicon particles via recombination of the carbon fragments. The neuron-like Si-CNT composite not only contributes to a high electronic conductivity and mechanical stability of the silicon anode, but also effectively offsets the large volume change of the Si particles. The rate capability and cycling stability of the Si anode are significantly enhanced compared to that of the physical Si + CNT mixture. At an extremely high current density of 20 A g−1, the neuron-like Si-CNT composite still delivers a reversible capacity of 1161.5 mAh g−1. After 200 cycles, the capacity retention is obtained to as high as 96%, showing a great potential for practical application in advanced lithium ion battery industries. •Neuron like carbon nanotubes (CNTs) are grown on silicon nanoparticles.•A chemical vapor deposition method is used to prepare the Si-CNTs composite.•The capacity retention of Si-CNTs after 200 cycles of Li-storage is 96%.•The Si-CNTs composite exhibits improved conductivity and mechanical strength.