Li-Ca alloy-LiF hybrid layer formed in situ to realize high performance lithium metal batteries

The lithium metal anode is a desirable choice owing to its high theoretical specific capacity. Despite their promising potential, lithium metal batteries (LMBs) face significant challenges in practical applications, such as uncontrolled growth of lithium dendrites and an unstable interface that occurs during repeated deposition and exfoliation of the lithium anode Therefore, this study employs a simple chemical immersion method, which can not only construct a Li-Ca alloy protective layer to improve lithium-ion transport but also provide a LiF-rich interface to further enhance the mechanical strength of the protective layer. The obtained Li-Ca alloy-LiF hybrid layer shows improved performance of the lithium anode. The results indicate that the Li-Li symmetric cell composed of the treated Li can undergo stable cycling over 3000 h under various cycling conditions and also exhibit excellent cycle performance in the Li-LiFePO4 cell.