Roll-to-roll fabrication of lithium metal anodes with hierarchical lithiophilic structures and controlled deposition for enhanced stability

The practical application of lithium metal is hindered by dendrite growth and the formation of dead lithium, leading to short circuits and reduced lifespan. To overcome these challenges, 3D hosts have emerged as a promising solution to distribute current density across the entire host framework. However, lithium metal tends to deposit predominantly on the top surface due to lower mass-transfer overpotential, resulting in ineffective utilization of the rest of the host and dendrite growth. Herein, we introduce a novel and facile solution-combustion method to produce copper foams with varying lithiophilicity, followed by roll-pressing to create a hierarchically lithiophilic triple-layered copper foam (HLTL-CF). Employing the HLTL-CF directly in a lithium infusion process generates lithium-composite electrodes (Li@HLTL-CF). Through systematic SEM characterizations and COMSOL simulation, we confirm the bottom-up deposition mode of lithium in the HLTL-CF. The resulting Li@HLTL-CF exhibits remarkable stability, enduring over 1350 cycles under ultra-high current density (20 mA cm⁻²) and practical capacity (5 mAh cm⁻²) in symmetric cells. Moreover, when combined with high-loading LFP cathodes, the full cells retain 86.9 % capacity after 400 cycles at 1C. This study presents a facile and promising strategy to engineer lithium metal anode structures, enhancing stability and extending lifespan in energy storage applications.