Directed cross-sectional lithium growth enabled by a lithiophilic MnO₂-decorated carbon fabric for safe and durable lithium metal batteries

Uncontrolled dendrite growth at the anode/separator interface remains the primary obstacle for practical lithium metal batteries. Conventional strategies cannot steer lithium away from this hazardous zone. Here, we demonstrate a fundamentally distinct growth regime: directed cross-sectional lithium growth enabled by a three-dimensional carbon fabric decorated with MnO₂ nanosheets (CF@MnO₂). Unlike random or surface-confined plating, this lithiophilic host guides lithium nucleation and lateral propagation strictly along the cross-section. This unprecedented mode delivers three critical advantages: complete dendrite suppression by sequestering lithium within the host interior, seamless accommodation of volume changes, and eradication of dead lithium formation. Consequently, the CF@MnO₂ electrode achieves an outstanding Coulombic efficiency of 99.78% over 920 cycles at 4 mA cm −2 . Symmetric cells maintain stable overpotential for >180 h at 2 mA cm −2 . Full cells with LiFePO₄ cathodes deliver extended cycle life exceeding 700 cycles at 2C. By fundamentally redirecting lithium deposition from a hazardous surface-normal to a protective cross-sectional pathway, this work establishes a transformative design principle for intrinsically safe, high-energy lithium metal batteries.