LAUSR

Abstract Lithium (Li) metal is considered as the most promising anode material for the next-generation high performance Li batteries. However, the uncontrollable dendritic growth impedes its commercial application. Herein, we design a 3D Si@carbon nanofibers (CNFs) @ZnO-ZnO-Cu skeleton (SCZ) for guiding the homogeneous bottom-growth of Li metal. The top LixSi@CNFs and bottom LiyZn@CNFs layers could form conductivity and overpotential gradient to avoid the “top-growth” of Li metal. Moreover, the top lithiophilic LixSi@CNFs layer could regulate the nucleation and deposition of Li-ions even if the lithium dendrites grow out of the skeleton under high capacity Li deposition (30 mAh cm-2). As a result, the SCZ-Li||LiFePO4 full cell delivers a high capacity of ∼104 mAh g-1 (∼94.82% capacity retention) after 2000 cycles at 5 C, elucidating the potential application of the 3D double-gradient Li metal composite anode.