Preparation method of flexible composite nanomaterial for lithium ion battery anode

The invention discloses a preparation method of a flexible composite nanomaterial for a lithium ion battery anode. The preparation method comprises the following steps: step 10) dissolving a solute into a methyl alcohol, ethanol, acetone, N,N-dimethylformamide or N,N-dimethylacetamide solvent; step 20) preparing carbon nano tube paper; step 30) mixing polyacrylonitrile and a nickel salt to prepare a precursor solution; spraying the precursor solution onto the carbon nano tube paper to form carbon nano tube paper coated with the nickel salt; and raising the temperature of the carbon nano tube paper to obtain carbon nano tube paper loaded with nickel nano-particles; step 40) putting the carbon nano tube paper loaded with the nickel nano-particles into a tin salt solution so as to obtain a carbon nano tube paper and tin composite nanomaterial; and step 50) spraying a spraying solution onto the surface of the carbon nano tube paper and tin composite nanomaterial, and drying to obtain a carbon nano tube paper, tin and graphene quantum dot composite nanomaterial. The composite nanomaterial prepared by the invention has good electrical conductivity, capacity and cycle life.