Lithiophilic Ag/Li composite anodes: Via a spontaneous reaction for Li nucleation with a reduced barrier

Infinite volume expansion and high reactivity severely hinder the commercial applications of lithium metal batteries. Moreover, the short circuit caused by Li dendrites is fatal for the long-term performance of lithium metal batteries and may cause safety problems. Herein, lithiophilic silver/lithium (Ag/Li) composite anodes are synthesized via a spontaneous displacement reaction between silver nitrate and Li foil at room temperature, which can settle the above challenges by regulating Li nucleation and homogenizing Li-ion flux. Benefiting from the lithiophilic design, Li ion realizes zero nucleation overpotential on the as-obtained Ag/Li anodes with abundant spherical silver nanoparticles. Additionally, the by-product, lithium nitrate, acts as an electrolyte additive, which further ensures uniform Li deposition. Consequently, Ag/Li symmetric cells demonstrate ultralong lifespan with repeated plating/stripping for 1000 cycles at the current densities of 1 mA cm^-2 and 5 mA cm^-2, with negligible voltage fluctuations. Furthermore, the full-cell devices, paired with LiFePO₄, also exhibit excellent electrochemical performance. The facile and effective strategy provides a promising prospect for commercial applications of lithium metal batteries.