A Pore‐Forming Strategy Toward Porous Carbon‐Based Substrates for High Performance Flexible Lithium Metal Full Batteries

Self‐standing carbon‐based substrates with satisfied structural stability and property adjustability have promising applications in flexible lithium (Li) metal batteries (FLMBs). Current strategies for modifying carbon materials are normally carried out on powder carbon, and very few of them are suitable for self‐standing carbon substrates. Herein, a pore‐forming strategy based on the redox chemistry of metallic oxide nanodots is developed to prepare two porous carbon substrates for anode and cathode. Starting with cotton cloth, the resulting hollow carbon fibers substrate with nanopores effectively prevents from Li dendrites formation and large volume change in lithium metal anode (LMA). Simulations indicate that the porous structure leads to homogeneous ion flux, Li‐ion concentration, and electric field during Li deposition. Li symmetrical cell based on this substrate remains stable for 8300 h with an ultralow voltage hysteresis of 9 mV. Via a similar route, porous carbon cloth substrate is obtained for subsequently seeding V 2 O 5 nanowires to prepare the cathode. The assembled FLMBs pouch cell delivers a capacity of 8.2 mAh with a high capacity retention of ~100% even under dramatic deformation. The demonstrated strategy has far‐reaching potential in preparing free‐standing porous carbon‐based materials for flexible energy storage devices.