Unravelling the effect of interlayer metal materials on Li deposition in zero-excess Lithium batteries

Zero-excess Li batteries (ZELBs), where the anode forms during operation, are promising for next-generation energy storage systems. Modifications on the current collector surface with interlayer materials are crucial for ZELBs to avoid erratic Li deposition and improve cycling stability. The formation of solid solutions during Li deposition can act as a buffer layer, lowering the Li nucleation overpotential and limiting the formation of dendritic structures. In this study, first-principles calculations are used to investigate Li deposition on 19 interlayer metals, including a comprehensive list of those forming solid solutions with Li (Ca, Mg, Zn, Al, Ag, Au, Pt, Pb, Tl, In, Y, Tm, Sb, and Pd). Investigations of the adsorption and diffusion of Li elucidate that the formation of Ca–Li, Mg–Li, Zn–Li, and Sb–Li solid solution alloys during Li deposition has lithiophilic characteristics, promoting increased Li binding strength. Furthermore, for Sb–Li alloys and all other interlayer metals studied here, the formation of a solid solution with Li lowers Li diffusion barriers on the surface, facilitating faster Li diffusion. A relationship between the Li deposition overpotential and diffusion barriers reveals that Mg–Li alloys with low Li content ( < 11 . 25 at.% Li), as well as Li–In, Li–Tl, Li–Pb, Li–Tm, and Li–Y alloys with high Li atomic concentration ( > 98 at.% Li), offer the best performance for efficient Li deposition. The fundamental understanding provided in this work acts as a guideline for the engineering of new interlayer metals for ZELBs. • 19 interlayer metals are screened for efficient Li deposition. • Formation of Ca–Li, Mg–Li, Zn–Li, and Sb–Li alloys promote lithiophilic surface sites. • Alloys promoting low Li nucleation overpotential and fast Li diffusion are suggested. • Computational models of Mg–Li solid solution alloys surfaces are proposed.