A Lithiophilic 3D Conductive Skeleton for High Performance Li Metal Battery

Li metal is considered as an ideal anode material for next-generation high energy density batteries. However, the huge volume change during cycling and uncontrollable Li dendrites growth represent the main issues of a Li metal anode, resulting in a short lifespan, low Coulombic efficiency, and serious safety risks. Herein, a modified 3D conductive skeleton is obtained via a facial replacement reaction to introduce a Sb layer on the surface of a commercial Cu foam. In this way, a lithiophilic Li–Sb layer can be in situ formed during the cell activation. This modified Cu foam can accommodate the volume changes accompanying the cycling and reduce the local current density. The lithiophilic Li–Sb layer can guide smooth Li plating/stripping without forming Li dendrites. Consequently, such a Sb-modified Cu foam substrate displays a stable and high Coulombic efficiency over 600 cycles in half cells and a super long lifespan over 1800 h in asymmetrical cells. Moreover, the lithium full cells constructed by coupling it with a LiFePO4 cathode also demonstrate excellent cycling performance over 300 cycles at 5 C.