Stabilizing Lithium Metal Batteries by Synergistic Effect of High Ionic Transfer Separator and Lithium–Boron Composite Material Anode

• Published in: ACS nano Vol. 17; no. 20; pp. 20315 - 20324
• Main Authors: Naren, Tuoya, Jiang, Ruheng, Qing, Piao, Huang, Shaozhen, Ling, Canhui, Lin, Jialin, Wei, Weifeng, Ji, Xiaobo, Chen, Yuejiao, Zhang, Qichun, Kuang, Gui-Chao, Chen, Libao
• Format: Journal Article
• Language: English
• Published: American Chemical Society 24-10-2023
• Subjects: lithium boron anode; graphene oxide; high lithium ion transport; functionalized separator; lithium metal batteries
• ISSN: 1936-0851; 1936-086X
• DOI: 10.1021/acsnano.3c06336

The development of lithium (Li) metal batteries (LMBs) has been limited by problems, such as severe dendrite growth, drastic interfacial reactions, and large volume change. Herein, an LMB (8AP@LiB) combining agraphene oxide-poly­(ethylene oxide) (PEO) functionalized polypropylene separator (8AP) with a lithium–boron (LiB) anode is designed to overcome these problems. Raman results demonstrate that the PEO chain on 8AP can influence the Li+ solvation structure in the electrolyte, resulting in Li+ homogeneous diffusion and Li+ deposition barrier reduction. 8AP exhibits good ionic conductivity (4.9 × 10–4 S cm–1), a high Li+ migration number (0.88), and a significant electrolyte uptake (293%). The 3D LiB skeleton can significantly reduce the anode volume changes and local current density during the charging/discharging process. Therefore, 8AP@LiB effectively regulates the Li+ flux and promotes the uniform Li deposition without dendrites. The Li||Li symmetrical cells of 8AP@LiB exhibit a high electrochemical stability of up to 1000 h at 1 mA cm–2 and 5 mAh cm–2. Importantly, the Li||LiFePO4 full cells of 8AP@LiB achieve an impressive 2000 cycles at 2C, while maintaining a high-capacity retention of 86%. The synergistic effect of the functionalized separator and LiB anode might provide a direction for the development of high-performance LMBs.