MXene‐Engineered Ultrathin Conductive Meshes for High‐Rate and Long‐Life Lithium Metal Batteries

Although ultrathin lithium on copper foils addresses the issue of dendrite‐induced poor electron transport, their practical application is fundamentally limited by the excessive mass of inactive copper, which severely degrades the energy density of lithium metal batteries. To overcome this trade‐off, we developed an ultralight conductive mesh by modulating a highly conductive MXene layer on a PET mesh scaffold, followed by the controllable electroplating of an ultrathin and conformal copper layer (∼400 nm). The anionic functional groups on MXene surface provide strong adsorption sites for Cu 2+ ions, facilitating uniform and ultrathin copper plating. After compositing with an ultrathin lithium foil, the resulting electrode exhibits a high tensile strength of 14.4 MPa and a high electrical conductivity of 5.1 × 10 5 S cm −1 , while maintaining a low fraction of inactive component. When paired with a high‐loading LiNi 0.8 Co 0.1 Mn 0.1 O 2 cathode, an Ah‐level pouch cell fabricated with this anode delivers a remarkable energy density of 462 Wh kg −1 , alongside superior rate capability (stable operation at 5 C) and long‐term cycling stability (280 cycles with 86% capacity retention).