Abstract: Described are processes for making graphene pellet (GP) with a three-dimensional structure. The process includes forming a nickel pellet from nickel powder to function as a catalyst for graphene growth, exposing the nickel pellet to a hydrocarbon under conditions sufficient to grow graphene, and etching nickel from graphene with an acid resulting in a graphene pellet. Also described is a process for making a graphene paper from the graphene pellet comprising applying a compression force to the graphene pellet sufficient to compress the pellet. Also described is a method for forming a graphene pellet composite useful as an electrode.