Ultrathin Al Foils to Fabricate Dendrite-Free Li-Al Anodes
Current research has made great progress on lithium dendrite issues by electrolyte and/or electrode engineering, but such modifications usually cause severe capacity loss due to the introduction of extra species in the cells. Herein, ultrathin aluminum foil has been employed to in-situ fabricate Li-Al alloy onto lithium metal as a protection layer. The nanoscale foil has an average thickness of only ˜160 nm and areal mass of 0.3 mg cm-2. The composite anodes with such protection layer exhibit significant improvement on cycling stability either in symmetrical cells or full cells by effectively regulating the lithium plating and alloying behaviors to avoid dendric morphologies at high plating current and capacities. Different characterization techniques confirm uniform lithium deposition on to the Li-Al alloy surface. Meanwhile, the protection layer also serves as a buffer to alleviate volume variation on cycling. The straightforward integration of ultrathin low-cost metal foil in lithium anode is a very competitive strategy for the practical development of lithium metal batteries.