The invention discloses a preparation method of a
silicon carbon negative
electrode precursor. The preparation method comprises the steps of adding nanometer
silicon powder and carbon micro
powder into an
organic solvent, and performing
grinding and dispersion to form paste A; adding a nanometer carbon material into the
organic solvent, and performing uniform dispersion to form paste B; adding a binding agent into the
organic solvent, and performing uniform dispersion to form paste C; mixing and uniformly dispersing the paste A, the paste B and the paste C to form paste D; and performing spraydrying
granulation on the paste D to obtain the
silicon carbon negative
electrode precursor. Multi-step dispersion is employed, the dispersion performance and the stability of the mixed paste are improved, the dispersion
process time is reduced, the dispersion efficiency is improved, a relevant risk such as
granulation plug is reduced, and subsequent application and
mass production are facilitated; meanwhile, the carbon micro
powder and the nanometer carbon material are introduced, on one hand, the problem of silicon
conductivity is solved, the
internal resistance is reduced, and the initialcoulombic efficiency and the rate performance are improved; and on the other hand, the
volume expansion during the charge-
discharge process of silicon is solved, the integral
expansion rate of the material is reduced, the material pulverization is prevented, and the cycle property is improved.