Electrochemical intercalation of lithium into multiwall carbon nanotubes

Electrochemical intercalation of lithium into carbon electrodes containing multiwall nanotubes produced by the arc-electric technique has been carried out in button cells. X-ray diffraction (XRD) and 7Li NMR spectroscopy coupled 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 intercalation process seems to be reversible and to proceed through the graphene walls via structural defects.