Binder less-integrated freestanding carbon film derived from pitch as light weight and high-power anode for sodium-ion battery

To realize the large scale application of sodium-ion batteries (SIBs), a stable, cost-effective anode is desired. Pitch is a potential low-cost precursor to synthesize soft carbon anode for SIBs. However, it exhibits poor Na-ion storage. Herein, we report the facile synthesis of pitch derived-binder less-metal free-freestanding anode for storing Na-ions by one-step pyrolysis process between the temperature range 700–1000 °C under nitrogen atmosphere. We replace conventional Cu-current collectors with non-graphitic carbon fiber (CFs) mats. The electrode architecture not only eliminates the metallic current collector, conductive diluents, and inactive organic binder but also provides an ideal porous network for sodium-ion and electrolyte diffusion into the bulk of the electrode. The freestanding electrode delivers a reversible capacity of 310 mAh g−1 in comparison to 180 mAh g−1 for the conventional electrode at the current density of 50 mA g−1. Good C rate performance and cycling stability over 500 cycles (at 1 A g−1) of this freestanding electrode indicate as a promising anode for SIBs. The evolution of plateau region capacity (