Highly ordered and high-aspect-ratio Au nanopatterns directly fabricated on Cu for efficient anode-less Li metal batteries†

Abstract

The development of anode-less lithium–metal batteries (ALLMBs) with high energy density is essential for advancing next-generation energy storage systems. However, challenges such as uncontrolled dendritic growth and rapid lithium depletion hinder their performance. This study presents the fabrication and evaluation of vertically aligned hole-cylinder Au nanopatterns with compositional control as novel current collectors for ALLMBs. The highly periodic 3D Au nanostructures, fabricated via secondary sputtering lithography (SSL), were compared with bare Cu and disk-shaped Au patterns to examine the influence of current collector topology on lithium deposition. The 3D hole-cylinder Au nanopattern exhibited significantly more uniform lithium growth, suppressed dendritic formation, and superior cycling stability, achieving high coulombic efficiency (CE) over 100 cycles. These improvements were attributed to the confinement effect of the lithiophilic 3D topology, which facilitated uniform lithium nucleation and deposition. Further optimization of lithiophilic properties was achieved by incorporating an Au–Ag multi-metal nanopattern, leveraging Ag's lithiophilicity alongside structural confinement. Full-cell tests under lean electrolyte conditions confirmed that the Au–Ag configuration delivers improved capacity retention and reduced lithium loss, outperforming bare Cu-based ALLMBs. These findings underscored the importance of integrating advanced structural designs with tailored metal compositions to develop scalable, stable, and energy-dense ALLMBs.