The invention relates to the field of
lithium battery negative electrodes, and discloses a method for producing a
lithium battery
silicon-carbon negative
electrode active material by magnetic coatingball milling. The preparation method comprises the following steps of: (1) mixing and ball-milling
silicon powder and
iron powder, and carrying out
vacuum annealing to obtain
powder A; (2) modifying
porous carbon powder by using an anionic surfactant, then mixing the modified
porous carbon powder with a ferrite precursor, deionized water and
anhydrous ethanol to prepare a turbid liquid, carrying out
ultrasonic oscillation, performing filtering, collecting the filter residue, and carrying out
vacuum sintering and
magnetization to obtain powder B; and (3) adding the powder A, the powder B and aPTFE
emulsion into deionized water to prepare turbid liquid, carrying out
ultrasonic dispersion, then performing standing and
settling, and granulating, annealing,
grinding and screening settled substances to obtain the
lithium battery
silicon-carbon negative
electrode active material. According to the preparation method, the uniformity and the compounding capacity of the silicon powder and the carbon powder are effectively improved through the
metal adsorption capacity of the magnetic material, the obtained silicon-carbon negative
electrode material has excellent cycle performance, meanwhile,the preparation process is simple, and the large-scale production potential is achieved.