Synergistic silicon oxide–carbon nanotube framework on carbon paper enabling uniform lithium deposition and stable cycling

The uncontrolled dendrite growth and unstable interfaces of lithium metal anodes remain major barriers to realizing high-energy lithium batteries. Here, we design a freestanding, lithiophilic, and conductive host composed of SiO x -decorated carbon nanotubes coated on carbon paper (SiO x /CNT/CP), engineered to regulate lithium nucleation and mitigate mechanical degradation. The SiO x particles serve as uniform nucleation seeds that facilitate homogeneous Li deposition, while the interconnected CNT/CP framework provides efficient electron transport. Operando dilatometry reveals a minimal volume variation of only 1.5%, evidencing excellent structural stability compared to previously reported Si- or carbon-based electrodes. The Li@SiO x /CNT/CP electrode demonstrates outstanding electrochemical stability, sustaining an ultralow overpotential of approximately 15 mV and stable cycling for more than 1250 h at a current density of 1 mA cm −2 with a fixed areal capacity of 1 mAh cm −2 . It also achieves a high Coulombic efficiency of 99.99% for over 620 cycles. When paired with an NMC622 cathode, the full cell retains 90% of its initial capacity after 100 cycles at a rate of 1 C. This work demonstrates how synergistic coupling between lithiophilic SiO x domains and CNT/CP scaffold enables dendrite-free Li deposition, low polarization, and suppressed volume fluctuation, advancing the practical realization of durable lithium metal batteries.