Battery and preparation method of battery negative electrode material

The invention discloses a battery and a preparation method of a battery negative electrode material, and belongs to the technical field of battery materials, and the preparation method comprises the following steps: mixing nano metal powder, a magnetic metal material and a binder in a first part of solvent to obtain a mixture; stirring the mixture, and meanwhile, adding a second part of solvent to obtain negative electrode slurry; and coating the negative electrode slurry on a substrate material, and drying to obtain the negative electrode composite material. The battery negative electrode material is prepared into a battery, a diaphragm is a polypropylene film, and the diameter of the diaphragm is 16-20mm; the electrolyte is a sulfide electrolyte or an oxide ceramic electrolyte, and the performance of the prepared battery is tested. According to the invention, by introducing the negative electrode composite material layer, the deposition of lithium is converted from micro-electric field and micro-point induc