Negative pole piece and preparation method thereof, lithium ion battery and power utilization device

The invention relates to a negative pole piece and a preparation method thereof, a lithium ion battery and an electric device. The negative pole piece comprises a current collector and a negative active layer covering at least one surface of the current collector; the negative active layer comprises a middle layer and an outer layer which are sequentially stacked on the surface of the current collector; the middle layer is made of silicon, the mass ratio of the silicon is larger than 50%, and the outer layer is made of a first conductive carbon material. In the negative electrode active layer, the middle layer is mainly made of silicon, the advantage of high specific energy of silicon can be fully played, the whole negative electrode plate has higher energy density, the outer layer is made of the first conductive carbon material, electrolyte reaction can be effectively prevented from generating an unstable solid electrolyte interface layer, and battery capacity attenuation can be delayed. 本申请涉及一种负极极片及其制备方法、锂离