Flexible composite current collector, preparation method thereof, pole piece and battery

The invention relates to the technical field of batteries, in particular to a flexible composite current collector, a preparation method thereof, a pole piece and a battery. The flexible composite current collector comprises a metal grating base material and composite materials which are coated on two surfaces of the metal grating base material and are filled in grating holes, the composite materials comprise high-molecular polymers and conductive agents, on one hand, the metal grating base material has the characteristic of light weight, and on the other hand, the metal grating base material has relatively good flexibility, so that the metal grating base material is more flexible. The two surfaces of the metal grid base material are coated with the composite material, and the grid holes are filled with the composite material, so that when the flexible composite current collector is applied to a battery, slurry is prevented from leaking from the grid holes, the composite material comprises a high-molecular po