One-Pot\nPreparation of Lithium Compensation Layer,\nLithiophilic Layer, and Artificial Solid Electrolyte Interphase for\nLean-Lithium Metal Anode

Abstract

Lithium metal is an ideal anode for\nhigh-energy-density batteries.\nHowever, the low Coulomb efficiency and the generation of dendrites\npose a significant limitation to its practical application, while\nthe excess lithium in the battery also generates serious safety concerns.\nHerein, a layer-by-layer optimized multilayer structure integrating\nan artificial solid electrolyte interphase (LiF) layer, a lithiophilic\n(Li_<i>x</i>Au alloy) layer, and a lithium compensation\nlayer is reported for a lean-lithium metal battery, where each layer\nacts synergistically to stabilize the lithium deposition behaviors\nand enhances the cycling performance of the battery. The optimized\nanode could effectively induce homogeneous reversible lithium deposition\nunder the synergistic effect of multilayer films and keep the integrity\nof the morphological structure unbroken during the deposition. The\npresence of the lithium compensation layer allows the half-cell to\nhave a high initial CE of 158.9%, and the action of the LiF layer\nand lithiophilic layer maintains an average CE of 98.8% over 160 cycles,\nwhich further demonstrates the stability of the structure. As a result,\nwhen combined with LiFePO₄ cathode, an initial capacity\nof 148 mAh g^–1 and a retention rate of 97.5% over\n130 cycles were achieved.