A high rate and long-cycle-life anode based on micrometer-sized Pb powder for sodium-ion batteries

Abstract Pb powder was investigated as an active material as anode for sodium-ion batteries. Precisely, a Pb anode comprising micrometer-sized Pb powder modified with multi-walled carbon nanotubes was fabricated. The anode showed an excellent rate capability, as well as reversible capacities of 370 mAh g−1 at 12.8 C (6208 mA g−1). In addition, the Pb anode exhibited a stable cycle life during 1000 cycles at 10 C with a high reversible capacity of 423 mAh g−1. Using electrochemical tests, scanning electron microscopy, and energy-dispersive X-ray spectroscopy, we revealed the origin of this excellent performance: the micrometer-sized Pb powder undergoes self-healing during cycling, resulting in fiber-like nanometer-sized Pb particles that reinforce the anode structure and provide fast electron transport pathways.