CF₄ Plasma-Generated LiF-Li₂ C₂ Artificial Layers for Dendrite-Free Lithium-Metal Anodes.

ABSTRACT: Lithium metal anodes have long been considered as "holy grail" in the field of energy storage batteries, but dendrite growth and large volume changes hinder their practical applications. Herein, a facile and eco-friendly CF₄ plasma treatment is employed for the surface modification of Li anodes, and an artificial layer consisting of LiF and Li₂ C₂ is fabricated for the first time. Experimental results and theoretical calculations reveal that the high adsorption energy of LiF and low Li⁺ diffusion barriers in Li₂ C₂ induce uniform nucleation and planar growth of Li, guaranteeing a stable and dendrite-free Li structure during the repeated plating/stripping process of cycling. Symmetric cells using CF₄ plasma-treated Li operate stably for more than 6500 h (at 2 mA cm^-2 and 1 mAh cm^-2 ) or 950 h (at 1 mA cm^-2 and 10 mAh cm^-2 ). When paired with a LiFePO₄ cathode, full batteries deliver a high reversible capacity of 136 mAh g^-1 (at 1 C) with considerable cycling stability (97.2% capacity retention over 200 cycles) and rate performance (116 mAh g^-1 up to 5 C). This powerful application of plasma technology toward novel LiF-Li₂ C₂ artificial layers provide new routes for constructing environment-friendly and high-performance energy storage devices.

SUBMITTER: Cao S 

PROVIDER: S-EPMC9313480 | biostudies-literature | 2022 Jul

REPOSITORIES: biostudies-literature