Abstract:

Lithium metal anode has a high theoretical specific capacity and low electrode potential. It is the ideal anode material for high-energy density secondary batteries. However, the growth of lithium dendrites and volume expansion during the cycling of lithium metal anode limit the commercial application of lithium metal batteries. In this study, the lithiophilic Ag-3D-Cu collector was prepared by electroless silver plating on the surface of foam copper to address dendrite growth and volume change in lithium metal anode during cycling. Silver particles can guide the uniform deposition of Li⁺ and inhibit the growth of lithium dendrites, and the three-dimensional porous structure of foam copper can effectively alleviate the volume expansion. The Ag-3D-Cu-30 s electrode obtained after a chemical silver plating time of 30 s exhibits a lower overpotential for nucleation and polarization compared to 3D-Cu electrodes while achieving a uniform lithium deposition morphology. The Li||Ag-3D-Cu-30 s cell also shows stable cycling for nearly 140 cycles, with an average Coulombic efficiency of 98%, demonstrating excellent cycling performance. The specific discharge capacity of Ag-3D-Cu-30 s/Li||LFP full cell was maintained after 360 cycles at 1.0 C, demonstrating excellent cycling stability. These results indicate that by electroless silver plating on the surface of foam copper to construct lithiophilic Ag-3D-Cu electrode, silver particles can guide the uniform lithium deposition, effectively reducing the nucleation and polarization overpotential of lithium deposition, and improving the Coulombic efficiency and cycle life of lithium metal batteries.

Key words: lithium metal anode, lithiophilic, Ag-3D-Cu current collector, electrochemical performance