Facile Synthesis of Ant‐Nest‐Like Porous Duplex Copper as Deeply Cycling Host for Lithium Metal Anodes

• Published in: Small (Weinheim an der Bergstrasse, Germany) Vol. 16; no. 37; pp. e2001784 - n/a
• Main Authors: Lin, Kui, Li, Tong, Chiang, Sum‐Wai, Liu, Ming, Qin, Xianying, Xu, Xiaofu, Zhang, Lihan, Kang, Feiyu, Chen, Guohua, Li, Baohua
• Format: Journal Article
• Language: English
• Published: Weinheim Wiley Subscription Services, Inc 01-09-2020
• Subjects: Anodes; Copper; Cycles; deeply discharge/charge; Dendritic structure; duplex Cu networks; Electric fields; high areal capacity; Lithium; Lithium batteries; lithium metal anodes; Metal foils; Nanotechnology; Substrates; Sulfurization; sulfur‐assisted formation
• ISSN: 1613-6810; 1613-6829
• DOI: 10.1002/smll.202001784

Suppressing the dendrite formation and managing the volume change of lithium (Li) metal anode have been global challenges in the lithium batteries community. Herein, a duplex copper (Cu) foil with an ant‐nest‐like network and a dense substrate is reported for an ultrastable Li metal anode. The duplex Cu is fabricated by sulfurization of thick Cu foil with a subsequent skeleton self‐welding procedure. Uniform Li deposition is achieved by the 3D interconnected architecture and lithiophilic surface of self‐welded Cu skeleton. The sufficient space in the porous layer enables a large areal capacity for Li and significantly improves the electrode–electrolyte interface. Simulations reveal that the structure allows proper electric field penetration into the connected tunnels. The assembled Li anodes exhibit high coulombic efficiency (97.3% over 300 cycles) and long lifespan (>880 h) at a current density of 1 mA cm−2 with a capacity of 1 mAh cm−2. Stable and deep cycling can be maintained up to 50 times at a high capacity of 10 mAh cm−2.
A duplex Cu structure with an ant‐nest‐like network and a dense substrate is fabricated serving as both current collector and host for Li metal anodes. Uniform and deep Li deposition can be realized by the 3D interconnected architecture and lithiophilic surface of self‐welded skeleton. The duplex Cu‐based Li anodes deliver stable cycling performance under high capacity.