Large‐Area Lithium Electroplating on Copper Foil

• Published in: Advanced materials technologies 2024-09, Vol.9 (17), p.n/a
• Main Authors: Wang, Yao‐Xian, Hong, Shih‐Kuan, Hsu, Hsiao‐Ping, Lan, Chung‐Wen
• Format: Article
• Language: English
• Subjects: columnar Li Structure; high current density; high Li+ conductive SEI layer; lithium; thin films
• ISSN: 2365-709X; 2365-709X
• DOI: 10.1002/admt.202400116

Anode‐free lithium metal batteries have attracted much attention due to their high energy density and lack of excess Li. In this work, Li film is deposited on large‐area copper foil (64 cm2) with good uniformity by a self‐designed electroplating device that quickly assembles and can be operated outside the glove box. By adding the high concentration of LiNO3 into the lithium bis(trifluoromethylsulfonyl)azanide (LiTFSI)‐based electrolyte, the high Li+ conductive solid electrolyte interface (SEI) layer regulated the Li+ flux, forming the columnar structure at a high current density of 40 mA cm−2, and compact morphology at 60 mA cm−2. Even at 100 mA cm−2, Li film on copper foil (Li@Cu) maintains its macroscopic uniformity. Furthermore, electrolytes, additives, and temperature are further optimized. The symmetric Li@Cu || Li cell cycle life can extend to 80 cycles. This work provides essential information for future manufacturing processes and scale‐up. A large‐area electroplating setup for depositing lithium on a copper foil is proposed. By optimizing the electrolyte composition with a high LiNO3 amount, precise control over Li+ flux is achieved by facilitating a uniform ultra‐thin Li film at high current densities.