A Random–Aligned Carbon Nanofiber Interface Enhancing the Intrinsic Electric Field for High-Performance Lithium Metal Batteries

Dendrite growth and interfacial side reactions severely impair the stability of lithium negative electrodes. A deeper understanding of the structure–performance relationship between current collectors (CCs) and lithium deposition is crucial for addressing these challenges. In this study, a “random-to-aligned hierarchical porous carbon nanofibers” (r/a-HPCNFs) CC strategy was proposed to realize uniform bottom-up lithium-ion (Li⁺) deposition by analyzing the ion transport within aligned CNF channels. By constructing a top-random/bottom-aligned interface with different charge centers, the dielectric constant can be effectively adjusted, thereby promoting a polarization transformation of the intrinsic electric field and strengthening the driving force for Li⁺ migration toward the bottom of the CC. The symmetric cell assembled with Li-predeposited r/a-HPCNFs operates stably for over 6500 h at 5 mA cm^–2. With less Li predeposition (∼3 mAh, N/P = 2), r/a-HPCNF-based full cells (LiFePO₄, LiNi_0.8Co_0.1Mn_0.1O₂, and sulfur) deliver >80% capacity over 400, 260, and 200 cycles at 3, 2, and 0.5 C, respectively. These results highlight the key role of the random–aligned hierarchical architecture in intrinsic field regulation, enabling dendrite suppression and stable cycling.