Graphene–carbon nanotube nanocomposites that contain multitubular co-axial and hollow cavity microstructures are prepared. Nanometer-scale graphene sheets are anchored with oxalic acid and consequently linked to each other via oxalyl bonding, thereby self-assembling into numerous outer tubes with distinct borders and a homogeneous thickness along the innermost pristine tube, which acts as a template. The resulting interstitial inclusion of oxalic acid into the graphene stacking modifies both the surface and the bulk properties of the newly formed tubes. It is observed that the unique microstructure of the modified graphene–carbon nanotube nanocomposite significantly facilitates the insertion and extraction of lithium, demonstrating superior electrochemical performance as anodes for lithium-based batteries. This facile chemical approach provides a new graphene architecture, showing superior stability, for use as anode material in lithium ion batteries.