High Capacity Na-Ion Battery Anodes by Coating Multi-walled Carbon Nanotubes on the Ni-Sn Foam Substrate

Abstract

In this study, Ni/multi-walled carbon nanotube (MWCNT) and Ni-Sn/MWCNT electrodes were fabricated by coating MWCNTs on Ni and Ni-Sn foam substrates using an electrophoretic deposition process. The anodic performance was examined by a chronopotentiometry method for adsorption of sodium (Na) in Na-ion batteries, where Ni/MWCNT and Ni-Sn/MWCNT nanocomposites were used as working electrodes in a three-electrode cell. Our results showed that, while the discharge capacity of the Ni/MWCNT electrode remained constant to approximately 200 mAh g1, a record-high initial discharge capacity of 2500 mAh g1 was obtained for the Ni-Sn/MWCNT nanocomposite electrode at a current of 1 mA. Increasing the cycle number indicated that 890 mAh g1 was the capacity of Ni-Sn/MWCNT after 50 cycles, which was attributed to the solid electrolyte interface formation. The presence of MWCNTs provided cycle stability, thus making the resulting electrodes appropriate for Na-ion battery applications with high capacity.