Triple–Functional Interface Regulation of DMSO-MMT/XG-Modified Copper Collector: Ion Channel Optimization, Interfacial Stabilization, and Dendrite-Free Lithium Metal Anodes

Lithium metal batteries (LMBs) emerge as prospective candidates for high-performance energy storage systems due to their exceptionally high theoretical energy storage density, simplified manufacturing process, as well as favorable cost-effectiveness. Nevertheless, uncontrolled lithium dendrite propagation and rapid capacity fade are caused by the pronounced reactivity of lithium metal coupled with the inadequate stability of the solid electrolyte interphase (SEI). To address these issues, we develop a triple-functional interface regulation strategy using DMSO-intercalated montmorillonite (DMSO-MMT) and xanthan gum (XG)-modified copper collector, enabling ion channel optimization, interfacial stabilization, and dendrite-free lithium metal anodes. The lamellar DMSO-MMT, synergized with XG’s deprotonated –COO–, Li+, and undercoordinated Al3+ sites of MMT, constructs a 3D ion-conducting network that optimizes ion transport, stabilizes the electrode–electrolyte interface, and mitigates lithium volume fluctuations, thereby realizing an anode free of dendrites alongside a steady interface. Electrochemical characterizations show that the modified cell achieves long-term cycling durability over 2400 h at 0.3 mA cm–2, it simultaneously retains a near-perfect Coulombic efficiency (99.7%) and excellent Li+ deposition and stripping reversible behavior. Even during extended cycling, the formation of lithium dendrites is markedly restrained. This interface modulating tactic, which combines ion transport channel optimization effect of DMSO-intercalated montmorillonite with the interface-regulating ability of XG-LITFSI offers a promising approach for the development of stable lithium metal anodes in high-performance lithium metal batteries. Thereby paving the way for the advancement of next-generation high-energy-density lithium metal batteries.