Revitalizing dendritic lithium with atomic modulator-decorated suspension electrolyte for durable lithium metal batteries

Lithium metal anodes suffer from dendrite growth, unstable solid electrolyte interphase, and “dead Li” owing to high barriers and inhomogeneous Li$^+$ desolvation/diffusion kinetics. Here, we present the suspension electrolyte endowed with atom-level catalytic inorganic particles of single atomic cobalt on defect-rich ZnO$_{1−x}$ nanoparticles (SACo@ZO) in a carbonate-based electrolyte, enhancing desolvation/diffusion kinetics and revitalizing dendritic Li. As systematically investigated by in situ electrochemical sum frequency generation (SFG) spectroscopy together with theoretical simulations, the SACo@ZO-assisted suspension electrolyte decreases the potential threshold down to 20 millivolts for driving interfacial desolvation rapidly, providing uniform solvation-free Li$^+$/Li$^0$ flux and capability in revitalizing dendritic Li. Consequently, we achieve a smooth but dense Li plating behavior under room or low-temperature surroundings, lasting for a long life span of 1600 hours. Meanwhile, the practical Li-LiFePO$_4$ cell with SACo@ZO reserves the capacity retention of ~100% at 0.5 C and survives for 1000 cycles under 0°C, demonstrating the feasibility of atomically catalytic suspension electrolyte for high-performance dendrite-free Li metal batteries.