The present invention discloses a 
graphene / CNTs / Super-P composite electric conduction agent, a composite electric conduction agent 
slurry, and preparation methods of the 
graphene / CNTs / Super-P composite electric conduction agent and the composite electric conduction agent 
slurry, wherein the composite electric conduction agent comprises 
graphene, CNTs (carbon nano-tubes) and Super-P (electric conduction 
carbon black). The preparation method comprises: adding a graphene 
oxide slurry, carbon nano-tubes, electric conduction 
carbon black and a surfactant to a reaction kettle, uniformly stirring, carrying out complete 
ultrasonic dispersion, 
drying, crushing, adding the crushed mixture to a 
muffle furnace, puffing in air, carrying out a 
reduction treatment in an 
inert atmosphere, and cooling to a 
room temperature to obtain the composite electric conduction agent 
powder, wherein the composite electric conduction 
powder can further be mixed with a 
solvent, and stirring and 
ultrasonic dispersion are performed to prepare the composite electric conduction agent slurry. According to the present invention, the composite electric conduction agent has excellent performances, and is suitable for being used as the electric conduction agent of power 
ion batteries; and the used preparation process has characteristics of simpleness and low 
energy consumption, and is suitable for large-scale industrial production.