Surface modification of Ni foam for stable and dendrite-free lithium deposition

Abstract

Lithium metal anodes are recognized as one of the most promising anodes for high-energy–density devices. However, the host-less nature of lithium tends to induce dendrite growth during repeated plating/stripping, leading to short cut of the batteries and safety issues. Therefore, the design of a lithiophilic host with a special three-dimensional (3D) porous structure to regulate lithium deposition and suppress dendrite growth is of particular importance. In this work, a 3D porous lithiophilic host for lithium metal was prepared via the surface modification of Ni foam in nitrate acid. Li-NiO/NF anode was prepared through the infusion of molten lithium into the porous host. Vertical aligned lithiophilic NiO nanosheet arrays homogenize Li ion flux and provide plenty of void space for the dense and uniform deposition of lithium, suppressing the uncontrolled growth of lithium dendrites. Excellent electrochemical performance of the Li-NiO/NF anode is demonstrated in both symmetric cells and full cells coupled with LiFePO4 cathode. A prolonged cycle life span over 1000 h is maintained for a Li-NiO/NF|Li-NiO/NF symmetric cell. An excellent capacity retention rate of 92.6% and high Coulombic efficiency of 99.2% are achieved for the Li-NiO/NF|LiFePO4 full cells after 500 cycles at 10 C.