Current collector and preparation method thereof, electrode plate, secondary battery and electric device

The invention provides a current collector and a preparation method thereof, an electrode plate, a secondary battery and an electric device. According to the current collector, the structure of the high-strength current collector is designed, so that the thickness of the first region is greater than that of the second region, the internal resistance of the first region can be correspondingly reduced, the current conduction capability of the first region can be improved, the polarization degree of the high-strength current collector can be reduced, and the performance of the battery can be further improved.