Highly-lithiophilic Ag@PDA-GO film to Suppress Dendrite Formation on Cu Substrate in Anode-free Lithium Metal Batteries

Lithium metal establishes a promising anode, but it suffers from dendrite growth. Constructing a current collector with stable artificial solid electrolyte interphase (SEI) and lithiophilic matrix is highly considered for achieving uniform lithium (Li) deposition. In this work, lithiophilic silver nanoparticles with polydopamine (Ag@PDA) were synthesized successfully and coated on the copper (Cu) current collector to use as a nucleation seed to improve the lithium nucleation. More importantly, graphene oxide (GO) was effectively coated on the top of Ag@PDA to act as artificial SEI to buffer the Li-ion distribution in anode free lithium metal batteries (AFLMBs). Thus, the synergistic effect of the modified electrodes displays a uniform Li metal deposition and dendrite free morphology during repeated cycling. Accordingly, the Cu|Ag@PDA//Li, and Cu|Ag@PDA-GO//Li cells demonstrate relatively uniform lithium nuclei, lower nucleation overpotential, and higher CE compared to the uncoated electrode. Besides, the Cu|Ag@PDA-GO//NMC full cell owns higher average Coulombic efficiency (~ 98.6%) and higher capacity retention (~ 55.7%) after 60 cycles within 5% fluoroethylene carbonate (FEC) in the carbonate-based electrolyte at 0.5 mA cm−2. While, the bare copper only achieves, 94.4% and 4.3% average Coulombic efficiency and capacity retention, respectively. Therefore, a lithiophilic matrix integrated with an artificial SEI coating on the Cu substrate offers a feasible way for the inhibition of lithium dendrite and electrolyte decomposition in the anode free lithium metal batteries (AFLMBs).