Facile one-step vulcanization of copper foil towards stable Li metal anode

Lithium metal has been regarded as the ultimate anode for next-generation rechargeable batteries with high energy density. However, its high reactivity and dendrite growth seriously limit its commercial application, which can be well addressed by realizing uniform Li deposition. Here, we report a facile and scalable one-step vulcanization method to modify commercial Cu foil with lithophilic Cu2S. The in situ formed Cu2S layer can not only promote the homogeneous deposition of Li via its lithophilic nature, but also benefit the formation of a stable solid-electrolyte interphase during initial activation. The Cu2S-modified Cu current collector realizes dendrite-free Li plating/stripping and thus exhibits stable cycling performance with a high Coulombic efficiency, even with a large capacity of 4 mA h cm−2. A full-cell consisting of a Cu2S/Cu-Li anode and a LiFePO4 cathode exhibits greatly improved cycling stability and enhanced Coulombic efficiency, demonstrating the effectiveness and practicability of the proposed Cu2S/Cu foil in the field of rechargeable Li metal batteries.