NOUFERROUS METALLURGICAL EQUIPMENT

To address silicon phase coarsening and inhomogeneous particle distribution in Al-Si alloys caused by non-uniform cooling rates during rapid solidification, the study innovatively integrates single-roller rapid solidification, lanthanum (La) modification, and acid etching. The influence of the synergistic effect of La modification and rapid solidification process on the morphology evolution and electrochemical performances of eutectic silicon in Al-12 wt.% Si alloy was investigated through XRD, SEM, EDS, XPS, CV, and GITT analyses. Results demonstrate that under 10m/s roller speed, 1% La modification achieves nanoscale refinement of eutectic silicon, transforming micron-sized dendritic structures into 50~150nm nanoparticles. The structural optimization reduces the average pore size from 18.81nm to 15.51nm and decreases the specific surface area to 61.88m²/g. Concurrently, the electrochemical performance of the prepared silicon anodes is improved. La-1% silicon anode delivers an initial Coulombic efficiency of 88.3% and a reversible specific capacity of 1421.4mAh/g after 50 cycles at 0.5A/g with reduced RSEI and Rct values. And La-1% silicon anode displays outstanding rate performance, achieving a reversible specific capacity of 1117.24mAh/g at 2.0A/g with enhanced D_Li+. The D_Li+ during intercalation and deintercalation are 2.3×10-¹²~1.9×10^-11cm²/s and 3.2×10^-12~5.8×10^-11cm²/s, respectively. The preparing strategy provides a new idea for the controllable and large-scale preparation of high-performance silicon anode.