Cable-like polyimide@carbon nanotubes composite as a capable anode for lithium ion batteries

• Cable-like PI@CNTs is designed and prepared via an in-situ polymerization approach. • The PI@CNTs anode exhibits far better long-term cycling performance than pure PI. • The structure of PI@CNTs facilitates Li ion diffusion and electron transportation. Polyimide (PI) with C = O groups and C 6 rings is considered as a promising anode material for lithium ion batteries. However, the potential application of PI is extremely hindered by its inherent properties with unsatisfied lithium ions diffusion and electron conductivity. Herein, the PI nanoflakes are grown on the carbon nanotubes (CNTs) to construct a cable-like structure (PI@CNTs) via an in-situ polymerization approach. The dispersed PI nanoflakes provide shorter lithium ion transmission distance and the CNTs substrate promotes electron transportation, leading to enhanced electrochemical performance. When served as anode material, PI@CNTs exhibits a specific capacity of 493 mAh g −1 at 1 A g −1 after 2000 cycles, demonstrating remarkable long-term cycling properties. Moreover, the kinetic analysis reveals that the increased capacity can be ascribed to an enlarged diffusion-controlled process. In addition, the COMSOL simulation displays the high concentration of Li ions flux on the PI@CNTs surface. This work suggests a facile strategy to fabricate capable hierarchical polymer electrode materials for lithium ion batteries.