Negative current collector and manufacturing method thereof, negative pole piece, secondary battery and electric device

The invention relates to a negative electrode current collector, and at least one side surface of the negative electrode current collector is provided with a LixM alloy layer, where 0 lt; x is smaller than or equal to 4.4, and M comprises at least one of elements of the third main group, elements of the fourth main group, magnesium, zinc, vanadium, iron, cobalt, phosphorus and sulfur. The invention also relates to a preparation method of the negative current collector, a negative pole piece, a secondary battery and an electric device. The negative electrode current collector is provided with the pre-lithiation layer, so that the surface lithium affinity of the current collector can be improved, uniform deposition of lithium is induced, meanwhile, the loss of active lithium in the formation process can be compensated, and the first coulombic efficiency of the secondary battery is improved; and meanwhile, the lithium content in the pre-lithiation layer can be adjusted as required, so that accurate lithium supplementation is realized, and the cycle life of the secondary battery is prolonged.