The invention relates to a composite
current collector with electrical
interconnection and a through-hole structure, a preparation method thereof, battery pole pieces and a
lithium ion battery, and belongs to the technical field of
lithium ion batteries. The preparation method of the composite
current collector includes the following steps: (1) coloring,
casting and forming to prepare a
polymer base layer; (2) carrying out first vacuum
metal plating on the surface of the
polymer base layer; (3) making holes in the surface of the
metal-coated
polymer layer; and (4) carrying out second vacuum
metal plating on the surface of the polymer layer. The prepared
current collector is of an inner and outer double-layer structure with the through-hole structure. The inner layer is a polymer layer withthe through-hole structure, and the surface
layers are metal coatings. The metal coatings cover the surface of the through holes, the through holes communicate the metal coatings. The preparation method is simple and easy in large-scale production, and can customize the thickness and hole structure distribution according to specific application indicator. Compared with a conventional foil material, the composite current collector with the electrical
interconnection and the through-hole structure has the advantages of light weight, bending resistance, low cost and the like, and has a significant effect on the
energy density improvement of the battery.