The invention provides a composite
current collector which comprises at least two composite
layers and a splicing fixing layer, the two composite
layers are respectively a conductive layer containing a carbon material and a carrier layer containing a non-metallic material with holes, the conductive layer is connected with the carrier layer, and the edges of the conductive layer and the carrier layer are spliced and fixed through the splicing fixing layer. The weight of the
current collector is reduced, so that the
mass energy density of a battery is improved, the cycle life of the battery is prolonged, the overall
structural stability of the
current collector is improved, the cost is low, the
lithium ion battery comprises a shell and a
battery cell, the
battery cell is arranged in the shell, and the
battery cell comprises a positive
electrode, a negative
electrode and an isolating membrane between the positive
electrode and the negative electrode; the positive electrode and the negative electrode of the
lithium battery comprise the composite current collectors, the positive electrode and the negative electrode of the
lithium battery are made of the composite current collectors, the
mass energy density of the
lithium battery is improved, the cycle life of the
lithium battery is prolonged, and the production cost is reduced.