Flexible Ti₃C₂ MXene-lithium film with lamellar structure for ultrastable metallic lithium anodes

Metallic lithium is one of the most promising anode materials for rechargeable lithium-based batteries owing to its high theoretical capacity of 3860 mA h g⁻¹. However, several severe issues such as uncontrollable lithium dendrites and infinitely large volume change are urgently needed to be solved, since they cause very short cycle life and severe safety hazards. Here we explore an effective strategy to create lamellar structured flexible Ti₃C₂ MXene (graphene, BN)-lithium film anode, based on the unique ductility of metallic lithium and lubricity of these nanosheets. By harnessing the lithiophobic property of atomic layers, not only the nucleation and growth of lithium dendrites can be efficiently controlled, but also the plating lithium is well confined in the nanoscaled gaps of above nanosheets. As a consequence, the optimal Ti₃C₂ MXene-lithium film anode exhibits significantly low overpotential (32 mV at 1.0 mA cm^–2) with a very small increase of 1.5% in 200 cycles, flat voltage profiles and good high-rate performances (53 mV at 3.0 mA cm^–2).