Modified high-first-effect silicon-oxygen negative electrode material and preparation method thereof

The invention discloses a modified silicon-oxygen negative electrode material with high first efficiency. The modified silicon-oxygen negative electrode material comprises a silicon oxide, a pre-lithium silicon oxide, a middle protective layer and a conductive layer which are sequentially distributed from inside to outside, the invention also discloses a preparation method of the modified high-first-effect silicon-oxygen negative electrode material, which specifically comprises the following steps: dissolving the nano compound and the dispersing agent in ethanol, adding the high-first-effect silicon-oxygen negative electrode precursor, stirring, spray-drying, roasting, then adding into ethanol-graphene G dispersion liquid, and carrying out ultrasonic stirring, spray-drying and roasting to obtain the modified high-first-effect silicon-oxygen negative electrode material. The nano compound and the dispersing agent are combined with each other, so that coating is more uniform, nano silicon generated on the surfac