Facile construction of a hybrid artificial protective layer for stable lithium metal anode

Abstract

Lithium metal is considered as the ultimate anode for next-generation rechargeable batteries due to its high theoretical specific capacity and low electrochemical potential. However, the commercial application of lithium anode is hampered by its dendritic growth during the charging process resulted from the unstable lithium/electrolyte interface. Herein, we demonstrate the formation of a hybrid protective layer consists of LixAl, LiCl and organics on the lithium anode surface. This stable hybrid layer facilitates uniform distribution of Li-ion to eliminate the surface inhomogeneity and thus suppress the dendrite formation. As a result, the modified metallic lithium anode realizes long-term stable cycling with a minimal polarization at 1 mA cm−2 for 1000 h. Furthermore, cells with protected lithium as anode and LiFePO4 as cathode were cycled up to 600 cycles at a 1 C rate with higher capacity retention. This work presents an effective way to regulate a stable lithium anode-electrolyte interface with the formation of a hybrid artificial protective layer to advance lithium metal batteries, which may provide good references for the practical application of Li metal batteries.