Scalable synthesized high-performance TiO2-Si-C hybrid anode for lithium batteries

Abstract

At present, developing a simple strategy to effectively solve the shackles of volume expansion, poor conductivity and interface compatibility faced by Si-C anode in lithium batteries (LIBs) is the key to its commercialization. Here, low-cost nano-Si powders were prepared from Si-waste of solar-cells by sanding treatment, which can effectively reduce the commercialization cost for Si-C anode. Furthermore, micro-nano structured Gr@Si/C/TiO2 anode materials with graphite (Gr) as the inner core, TiO2-doped and carbon-coated Si as the outer coating-layer, were synthesized at kilogram-scale per milling batch. Comprehensive characterization results indicate that TiO2-doped carbon layer can improve the interface compatibility with the electrolyte, further promote the reduction of electrode polarization, and finally enhance the battery performance for the Gr@Si/C/TiO2 anodes. Accordingly, Gr@Si/C/TiO2 composites can output excellent LIB performance, especially with high initial coulombic efficiency (ICE) of 82.51% and large average reversible capacity of ∼ 810 mA h g−1 at 0.8 A g−1 after 1000 cycles. Moreover, Gr@Si/C/TiO2||NCM811 pouch full cells deliver impressive performance especially with high energy density of ∼ 489.3 W h kg−1 based on the total weight of active materials, suggesting its promising application in the high performance LIBs.