Films of Bamboo-like Carbon Nanotubes as Electrode Material for Rechargeable Lithium Batteries

Abstract

Films of bamboo-like carbon nanotubes (BCNTs) were grown directly on Cu substrates by hot filament chemical vapor deposition requiring no catalysts for growth. This is an efficient technique that yields a large density of active sites on the battery electrode. The thin films were characterized by scanning electron microscopy, transmission electron microscopy, and Raman spectroscopy. The electrochemical properties of these BCNTs were studied by cyclic voltammetry (CV) and charge-discharge measurements. CV results indicate the formation of a solid electrolyte interface. The initial discharge capacity was found to be 880 μAh cm-2 μ m-1, which is greater than the volumetric theoretical capacity of graphite, i.e., 84 μAh cm-2 μ m-1. The reversible capacity remains at 205 μAh cm-2 μ m-1 after ten cycles. The nanocavities of the BCNTs appear to have a significant role in the large capacity for reversible Li insertion. © 2007 The Electrochemical Society.