Electroplating CuO nanoneedle arrays on Ni foam as superior 3D scaffold for dendrite-free and stable Li metal anode

• Surficial CuO modification enhances Li affinity of Ni foam for easy thermal infusion. • The influence of different morphologies of CuO on guiding Li plating/stripping behavior is investigated. • CuO nanoneedle arrays can overcome the nucleation barrier and redistribute the Li + flux. • The composite electrode delivers outstanding electrochemical performances. Undesirable dendrite growth and infinite volume expansion are the major barriers to the potential application for next-generation safe Li metal batteries. To solve these problems, we herein report electroplating CuO nanoneedle arrays on Ni foam (NCNF) as 3D porous framework for Li metal batteries. The influence of different morphologies of CuO on guiding Li plating/stripping behavior has been investigated. The homogenous deposition of Li can be attributed to the interspace between the CuO nanoneedles, which is remarkably superior over granular CuO on Ni foam (GCNF) at high areal capacity. The hierarchical skeleton can not only decrease local current inhomogeneity but also alleviate the volume change of Li. The NCNF electrode delivers a higher Coulombic efficiency of Li deposition comparing with the bare Ni foam and GCNF. Furthermore, enhanced cycling stability with small overpotential can be achieved in symmetric cells. In a Li/LiFePO 4 full cell, the excellent cycling performance also proves the superiority of NCNF@Li composite electrode.