Electrochemical intercalation of lithium into multiwall carbon nanotubes

Electrochemical intercalation of lithium into carbon electrodes containing multiwall nanotubes produced by the are-electric technique has been carried out in button cells. X-ray diffraction (XRD) and Li-7 NMR spectroscopy cou pled with electrochemical characterisation allow us to study the structural modifications induced by the intercalation of the alkali metal between the graphene shells and the nature of interactions between lithium species and the host material. Furthermore, direct observation of individual nanotubes by transmission electron microscopy (TEM) reveals that while the lithiated nanotubes are intercalated very inhomogeneously, the electrochemical inter calation process seems to be reversible and to proceed through the graphene walls via structural defects. (C) 1999 Elsevier Science B.V. All rights re served.