Defective Nanoscale Patterning for Dendrite-Free Lithium Deposition: Leveraging Block Copolymer Nanolithography to Fabricate Engraved Nanodimple Anodes

Abstract

Lithium metal batteries offer high energy density but face commercialization challenges due to safety issues, primarily caused by the formation of lithium dendrite structures. To address this, a patterned copper (Cu) nanodimple anode using block copolymer nanolithography, designed to guide lithium deposition by leveraging surface-dependent binding energy variations is developed. High-resolution transmission electron microscopy and density functional theory calculations reveal that the nanodimple curvature contains defective sites that enhance lithium binding energy, confining lithium nucleation within the dimples. This confinement plays a key role in preventing dendritic growth during subsequent lithium deposition. Consistent and uniform lithium growth across these confined nucleation sites is further observed, even after the defective dimple curvature is covered with lithium. This demonstrates the critical role of initial nucleation and nanoscale patterning in promoting stable lithium growth. The engraved Cu nanodimple structure resulted in improved electrochemical performance, highlighting the synergy between computational modeling and experimental validation in designing defect-engineered anode substrates for safer and more efficient lithium metal batteries.