Positive current collector and preparation method thereof, positive plate and lithium ion battery

The invention belongs to the field of batteries, and particularly relates to a positive current collector, a preparation method thereof, a positive plate and a lithium ion battery. The positive electrode current collector comprises an aluminum foil, and the surface of the aluminum foil is provided with a pit; the pits are continuous in the width direction of the aluminum foil; and a porous carbon skeleton layer is also arranged on the surface of the aluminum foil. The pits are etched in the surface of the aluminum foil, and the porous carbon skeleton layer on the surface contains the cross-linked polymer, so that slurry blockage can be prevented, the ion conduction capability is improved, and the energy density of the battery is improved. 本发明属于电池领域，具体涉及一种正极集流体及其制备方法、正极片和锂离子电池。一种正极集流体，包括铝箔，所述的铝箔表面具有凹坑；所述的凹坑在铝箔宽度方向上为连续的；所述的铝箔表面还设置有多孔碳骨架层。本发明通过在铝箔表面刻蚀多条凹坑，并且表面的多孔碳骨架层中含有交联的聚合物，可以防止浆料堵塞，提高离子的传导能力，从而提高电池的能量密度。