Enhancement of Dendrite-Free Lithium Metal Anode Performance through LiF-Rich Protective Layer for Lithium Metal Batteries

Abstract

Lithium metal batteries represent a cutting-edge class of energy storage devices, yet the high surface diffusion energy barrier of lithium metal prompts preferential Li⁺ accumulation and deposition, fostering the growth of lithium dendrites. To address this challenge, a straightforward solvent-based approach is employed to create a LiF-rich protective layer on the lithium anode. The uniform LiF interface facilitates the transport of Li⁺ and effectively induces the uniform plating and stripping of lithium while inhibiting the formation of dendrites. Notably, the symmetric battery incorporating a lithium anode modified with appropriate LiF demonstrates substantially enhanced cycling performance. Importantly, the full cell matched with LiFePO₄ displays an initial capacity of 146.3 mAh g^-1 and a capacity retention rate of 92.7% after 300 cycles. Its practical application has also been verified in symmetric batteries and full batteries for PEO solid-state batteries. This work underscores the potential of the LiF protective layer to boost the dendrite-free lithium metal anode.