Electrostatic Dry Coating Strategies for Through-Plane Control of Electronic Pathways in Lithium-Ion Electrodes

The drive for higher energy density in lithium-ion batteries (LiBs) is constrained by transport limitations in thick electrodes. Addressing this challenge requires structural design concepts that simultaneously optimize electronic and ionic conduction while enabling sustainable manufacturing. Here, we demonstrate a solvent-free electrostatic dry-coating strategy that aligns anisotropic, micron-sized carbon fibers (CFs) along the through-plane direction, thereby constructing efficient long-range electronic pathways. X-ray laminography shows that applying an electrostatic field reduces the average CF orientation angle from 83° to 68°, achieving enhanced through-plane alignment. Electrochemical testing demonstrates that such alignment lowers electronic resistance by over two orders of magnitude, suppresses polarization, and preserves capacity at high rates. Complementary 3D simulations confirm that CF highways enhance conductivity and reaction homogeneity without impeding ion transport. This simple, scalable approach integrates high electrochemical performance with an environmentally benign process, paving the way for sustainable, high-energy-density LiB manufacturing.