Fly ashes as a sustainable source for nanostructured Si anodes in lithium-ion batteries

Recycling industrial wastes for high-value items is of strategic importance for commercial production. Fly ashes are solid waste by-products generated by coal-fired power plants. Although a large amount of annual output approach 150 million tons worldwide, fly ashes have been recycled merely into some low-value items. In order to realize the high additive value of fly ashes, we transform the solid waste fly ashes into nanostructured silicon powders and apply them as anodes active materials for lithium-ion batteries. The nanostructured silicon exhibits good electrochemical performance as lithium-ion batteries anodes with high rate capacity (1450.3 mAh g−1 at current density 4000 mA g−1) and reversible capacity (1017.5 mAh g−1 after 100 cycles), indicating that fly ashes can be a useful resource of anode materials to meet the need of high performance lithium-ion batteries.