Self-Assembled Conductive Metal-Oxide Nanofiber Interface for Stable Li-Metal Anode

Li-metal anodes promise to build high-energy-storage systems, but they suffer from safety problems from severe dendrite growth. Here, we develop a thin and conformal hybrid ionic and electronic conducting metal-oxide nanofiber interface to stabilize Li-anodes without forming dendrites. The thin ionic-conductive Li_0.33La_0.56TiO₃ (LLTO) nanofiber film is first fabricated by electrospinning followed by pyrolysis. After connecting with the electrolytes-wetted Li-metal anodes, due to the self-driven chemical reactions, LLTO is reduced, and a hybrid conducting interface is developed. The interface can act as a reservoir to redistribute the nonuniform Li-ion flux above the anode surface and reduce the driving force of dendrite formation by leveling electric potential distribution, enabling a stable Li plating-stripping with a low overpotential of 80 mV over 800 h at a high current of 5 mA/cm². More practically, the Li-LiNi_0.8Co_0.15Al_0.05O₂ cells deliver a high capacity of 147 mA h/g at 1 C with a Coulombic efficiency of 99% over 150 cycles, offering prospects to achieve reliable Li-metal batteries.