MOF-derived pearl-like nanospheres enable tailored regulation of interface ion transport in dendrite-free lithium metal batteries

Separators constitute vital components in high-energy-density lithium metal batteries (LMBs), yet their propensity to fail under lithium (Li) dendrite growth remains a critical limitation. In this work, we report a commercial Celgard separator engineered with pearl-like nanospheres (Celgard@PNS) to enable electrochemically stable and dendrite-free lithium metal anodes (LMAs). The PNS-functionalized layer in the Celgard@PNS ensures rapid and homogeneous Li ion flux, which stabilizes LMAs and effectively mitigates dendritic Li deposition. Moreover, the PNS modification fosters the development of a robust solid-electrolyte interphase (SEI) layer. The Celgard@PNS-based Li||Cu half-cell exhibits stable Coulombic efficiency for 110 cycles, and the corresponding Li||Li symmetric cell sustains long cycling stability (>900 h) at a high current density of 10 mA cm⁻² with an areal capacity of 1 mAh cm⁻². Impressively, when paired with a high-mass-loading NCM811 cathode (22.5 mg cm⁻²), the Li||NCM811 full cell retains 81.4 % of its initial capacity after 140 cycles at 0.5 C. These results underscore the potential of the Celgard@PNS separator for practical implementation in high-capacity LMBs.