Lithium metal anodes have attracted extensive attention owing to their high theoretical specific capacity. However, the notorious reactivity of lithium prevents their practical applications, as evidenced by the undesired lithium dendrite growth and unstable solid electrolyte interphase formation. Here, we develop a facile, cost-effective and one-step approach to create an artificial lithium metal/electrolyte interphase by treating the lithium anode with a tin-containing electrolyte. As a result, an artificial solid electrolyte interphase composed of lithium fluoride, tin, and the tin-lithium alloy is formed, which not only ensures fast lithium-ion diffusion and suppresses lithium dendrite growth but also brings a synergistic effect of storing lithium via a reversible tin-lithium alloy formation and enabling lithium plating underneath it. With such an artificial solid electrolyte interphase, lithium symmetrical cells show outstanding plating/stripping cycles, and the full cell exhibits remarkably better cycling stability and capacity retention as well as capacity utilization at high rates compared to bare lithium.

Tremendous efforts have been devoted to replace commercial graphite anode (372 mAh g−1) by group IV elements (Si, Ge, Sn) based-materials with high capacities in lithium-ion batteries (LIBs). The use of these materials is hampered by the pulverization of these particles due to the high volumetric change during lithiation and delithiation cycles, which leads to particles pulverization and destabilization of solid electrolyte interphase (SEI) films. These problems result in fast capacity fading and low Coulombic efficiency. Nanostructured materials show significant improvements in rate capability and cyclability due to their high surface-to-volume ratio, reduced Li+ diffusion length, and increased freedom associated with the volume change during cycling. However, the nanostructured active materials with high ratio of surface-to-volume increase the irreversible capacity due to the formation of more SEI films. Although the nanostructured materials active materials keep relatively stable during repeated cycles of lithiation/delithiation process, the SEI film continually breaks/reforms, lowing the Coulombic efficiency. Meanwhile, the high-cost, low Coulombic efficiency and low tapping density limit the commercialization of the nanostructured electrode materials. Therefore, it is urgent to find solutions which could take advantage of both long cycle life of nanomaterials within the group IV elements (Si, Ge, Sn) and high volumetric/gravimetric capacity of micro-materials in the group IV as well as elements (Si, Ge, Sn). This report presents an overview of the recently developed strategies for improving the group IV elements (Si, Ge, Sn)-based anodes performances in LIBs to provide a further insight understanding in designing novel anodes

Silicon has been perceived as one of the most promising anodes in the next generation lithium-ion batteries (LIBs) due to its superior theoretical capacity. However, bulk silicon experiences an enormous volume expansion during the lithiation/delithiation process, resulting in rapid capacity fading. And, its high-cost and low coulombic efficiency also present significant challenges for applications. Here, we presented a facile and large-scale approach for preparing micro-sized porous silicon by acid etching the abundant and inexpensive metallurgical Fe–Si alloy as a high-performance anode in LIBs. Profiting from the unique micro-sized structure, it exhibited a fantastic first-cycle coulombic efficiency of 88.1% and an excellent reversible capacity of 1250 mA h g⁻¹ at 500 mA g⁻¹ after 100 cycles. Furthermore, the micro-sized porous silicon without carbon coating could deliver a reversible capacity of 558 mA h g⁻¹ at a high current density of 5 A g⁻¹ due to the unique porous structure. This work provides a promising route for a large-scale production of high-performance micro-sized Si as anode materials in LIBs.