Interface Engineering with ZrS₂: Achieving 10000‐Cycle Lifespan in High‐Rate Sodium Metal Batteries

Abstract Sodium metal batteries (SMBs) have emerged as promising alternatives to lithium‐ion batteries for low‐cost, high‐energy‐density energy storage. However, their practical application is hindered by uncontrolled dendrite growth and unstable interfacial reactions. In this study, a ZrS₂‐based interlayer is introduced to enable dendrite‐free, high‐capacity SMBs with exceptional long‐term stability. The 2D ZrS₂ sheets form a tightly bonded interface with the Na metal, effectively suppressing parasitic reactions at the electrolyte|Na interface. Additionally, ZrS₂ offers strong Na⁺ adsorption and features confined 2D ion transport channels, which facilitate uniform, planar Na deposition decoupled from the desolvation process. Importantly, the ZrS₂ interlayer demonstrates high Na⁺ diffusivity and accommodates Na⁺ via a reversible intercalation mechanism, thereby maintaining structural integrity under high current densities and prolonged cycling. As a result, the ZrS₂‐modified Na anode achieves a remarkable cycle life of 4800 h at 2 mA cm⁻2 with an areal capacity of 10 mAh cm⁻2 in symmetric cells. In full‐cell configurations, it delivers outstanding cycling stability over 10000 cycles at an ultrahigh rate of 50 C. This work provides a new design paradigm for interfacial engineering in SMBs and demonstrates a practical route toward safe, high‐performance SMBs with enhanced durability.