▎ 摘　　要

NOVELTY - The graphene-carbon nanotube stack (30) includes first and second graphene layers (32,34), and carbon nanotubes (38) extending from the first graphene layer to the second graphene layer such that the first graphene layer is spaced away from the second graphene layer by the carbon nanotubes. The carbon nanotubes are electrically connected to the graphene layers. USE - Graphene-carbon nanotube stack for electrical energy storage device, such as supercapacitor or battery. ADVANTAGE - Graphene and carbon nanotube (CNT) are active materials that have electrical properties preferred for high-capacity electrical energy storage, particularly high surface area and high electrical conductivity. The CNT array of the graphene-CNT stack acts as a spacer to prevent graphene self-aggregation, maintaining a large active surface area. The optimized CNT length and short ion diffusion length within the graphene-CNT stack facilitate ion diffusion. Stable electrical and mechanical contact is generated between CNT and graphene due to the direct growth of CNT between the graphene layers. The fabrication process is based on fabrication steps that are simple and easily executed. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for a method of fabricating a graphene-carbon nanotube stack. DESCRIPTION OF DRAWING(S) - The drawing is a schematic illustration of a graphene-carbon nanotube stack and a schematized electrochemical reaction. Graphene-carbon nanotube stack (30) Graphene layers (32,34) Carbon nanotubes (38) Carbon nanotubes (40) Lithium ions (42)