LAUSR

The practical applications of lithium metal anodes have been severely hindered by the Li dendrite issue. Herein, we report a dual structure-material design strategy to fabricate a new type of separator using interconnected hollow porous polyacrylonitrile (PAN) nanofibers (HPPANF), which delivers controllable and dendrite-free Li depositions. The interconnected mesopores on HPPANF bridge the hollow interiors with the outside voids among the fibers, enabling outstanding electrolyte uptake capabilities for high ion conductivity, and nanolevel wetted electrolyte/anode interface for uniform Li plating/stripping. In parallel, the HPPANF separator enriched with polar groups acts as an exceptional polymer-based solid-state electrolyte, providing 3D ion channels for the transport of Li ions. Benefited from the dual structure-material design, the HPPANF separator induces uniform Li ion flux for dendrite-free Li depositions, which brings enhanced cycling stability (1300 h, 3 mA cm-2). This work demonstrates a new method to stabilize Li metal anodes through rational separator design.