Stabilizing Li Metal Anodes through a Novel Self-Healing Strategy

Poor stability is a long-standing problem preventing the practical application of Li metal anodes, which is fundamentally attributed to their fragile solid electrolyte interphase (SEI) layers that are intrinsically neither adaptable to the dynamic volume change nor self-healable after breakage. Here a Li metal anode is effectively stabilized by in situ integrating its SEI layer into a self-healable polydimethylsiloxane (PDMS) network cross-linked via imine bonding. The self-healing network enables the integrated SEI layer to readily accommodate the volume change but also to repair itself after breaking. Consequently, the resulting anode exhibits excellent cycling stability and a dendrite-free morphology. In a Li/LiFePO4 full cell, this strategy leads to capacity retention up to 99% and a Coulombic efficiency >99.5% after 300 cycles. Our investigation provides a novel self-healing strategy for developing stable Li-metal anodes aiming at high energy-density batteries.