A Three-Dimensional,\nFlexible Conductive Network Based\non an MXene/Rubber Composite for Lithium Metal Anodes

Flexibility enhancement is a pressing issue in the current\ndevelopment\nof advanced lithium-metal battery applications. Many types of organic\npolymers are inherently flexible, which can form a composite structure\nenhancing electrode flexibility. However, organic polymers have a\nnegative influence on the plating and stripping of lithium-metal anodes,\nand the large number of polymers block the pore of the material,\nreducing the utilization of the active site. Herein, we report a flexible\nporous substrate as an anode host based on a serine-modified three-dimensional\nstructure of MXene and epoxidized natural rubber composite (3D/MXene-S-ENR),\nin which lithium ions can uniformly deposit in the interconnected\npore structure. The 3D/MXene-S-ENR, having more nucleation sites,\ncan effectively improve the uniformity of lithium metal, which effectively\nreduces the local current density and inhibits lithium dendrites.\nCompared with the serine-modified MXene and the epoxidized natural\nrubber electrode (MXene-S-ENR), the 3D/MXene-S-ENR electrode has lower\noverpotential and stable cycling. The lithium–sulfur batteries\n(Li–S) based on the 3D/MXene-S-ENR anode and sulfur cathode\n(3D/MXene-S-ENR@Li|S/C) deliver a stable discharge capacity of 316.2\nmAh g<sup>–1</sup> after 350 cycles, with a Coulombic efficiency\nof 98.05%. Finally, we assembled a flexible pack battery, which demonstrates\nthe potential value of the 3D/MXene-S-ENR anode in high-performance\nflexible lithium–sulfur batteries.