Vesicle-shaped ZIF-8 shell shielded in 3D carbon cloth for uniform nucleation and growth towards long-life lithium metal anode

Abstract

Abstract Lithium metal has aroused extensive research interests as the anode for next-generation rechargeable batteries. However, the well-known dendritic Li growth and consequent safety issues still impair the long-term cycling performance. Herein, a hybrid structure composed of 3D carbon cloth and vesicle-shaped hollow ZIF-8 modification shell (HZS@CC) was prepared as a smart host for guiding uniform Li deposition. The long-range interconnected 3D carbon fiber network enables the reduced local current density with homogeneous electrons distribution. Synergistically, abundant surface polar groups and the ultrastructure on ZIF-8 particles effectively guide a well-distributed Li-ions flow to promote the uniform Li nucleation and growth. As a result, stable Li plating/stripping for 2000 h with a low overpotential (≈15 mV) at 1 mA cm−2 were achieved in symmetric cells. Coupling with LiFePO4 cathode, the full cell delivered long life over 1200 cycles at 6 C. This research demonstrated that a homogenization guiding of Li-ions is of great importance to better make use of the structural advantage of 3D hosts and achieve improved electrochemical performance.