Exploring an Interesting Si Source from Photovoltaic Industry Waste and Engineering It as a Li-Ion Battery High-Capacity Anode

Low cost electrode materials are essential for the expansion of the applications of large-format Li-ion batteries (LIBs). Kerf-loss (KL) Si waste from the photovoltaic industry represents a low cost, high-purity Si source for the production of high capacity anodes of LIBs. Producing an energy storage device from solar-panel industry waste is a potential environment-friendly energy development. This study addressed the challenges of employing KL Si as high-capacity LIB anode. The abrasive SiC particle impurities in KL waste powder were used not only as a milling agent to reduce silicon particle size but also as mechanically and electrochemically robust pillars that resist microstructural degradation of the electrode caused by the expansion of Si during lithiation. High energy ball milling of Si with rigid SiC produced fused nanosilicon particles that were supported on micrometer-sized SiC; this resulted in substantially mitigated capacity fading. In addition, an effective conducting network was formed by incorporating Ni into the Si agglomerates, enabling high rate density and maintaining high powder tap density. The resulting Si–SiC–Ni composite powder exhibits high capacity and long-term stability.