Ultrathin, Layer-by-Layer Assembled Lithiophilic Interlayers for Dendritic Growth-Suppressed Lithium Metal Anodes

Abstract

Lithium (Li) metal, recognized for its high energy potential, serves as a promising anode material in battery technologies. However, the growth of Li dendrites during charging and discharging cycles presents significant safety and durability challenges. To address these challenges, a novel strategy is developed employing an ultrathin, layer-by-layer (LbL) assembled multi-walled carbon nanotube forest (MWCF) interlayer that is uniquely composed of lithiophilic components without inactive binders. Strategically deposited on one side of the separator, the LbL-assembled MWCF interlayer ensures excellent electrical conductivity and forms seamless interfaces with the separator, optimizing ion transport and reducing local current density. This configuration allows for uniform Li plating while preventing dendrite penetration toward the cathode, thus enhancing safety and extending the cell's lifespan. This approach has demonstrates exceptional cycling stability, sustaining over 10 000 h of operation at 1 mA cm-2 and 1 mAh cm-2 in a symmetric Li | Li cell, surpassing previously reported results. Furthermore, an LiNi0.8Mn0.1Co0.1O2-based asymmetric cell exhibits remarkable durability, maintaining approximate to 81.9% of its capacity after 600 cycles at 1 C, and achieving an ultrahigh energy of 678 Wh Kg-1. An LiFePO4-based asymmetric cell also demonstrates superior cycling stability, further validating the effectiveness of our approach.