Li3N film modified separator with homogenization effect of lithium ions for stable lithium metal battery

• Published in: Progress in natural science Vol. 31; no. 6; pp. 845 - 851
• Main Authors: Yan, Zhongyun, Zhou, Cheng, Li, Cheng, Li, Yan, Shen, Chunli, Yan, Kaijian, Xu, Xu
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.12.2021; International School of Materials Science and Engineering,State Key Laboratory of Advanced Technology for Materials Synthesis and Processing,Wuhan University of Technology,Wuhan,430070,China
• Subjects: Functional separator; Li metal anode; Physical vapor deposition; Solid electrolyte interface; Physical vapor deposition; Li metal anode; Solid electrolyte interface; Functional separator
• ISSN: 1002-0071
• DOI: 10.1016/j.pnsc.2021.05.002

Lithium metal anode with high theoretical capacity is considered to be one of the most potential anode materials of the next generation. However, the growth of lithium dendrite seriously affects the application of lithium metal anode and the development of lithium metal batteries (LMBs). Herein, an ultrathin Li3N film modified separator to homogenize the lithium ions and protect the lithium metal anode was reported. Due to the intrinsic properties of Li3N, the functional separator possessed good thermal stability, mechanical properties and electrolyte wettability, and the homogenization of the lithium ion was realized without increasing the interface impedance. With this functional separator, the Li/Li symmetrical cell could achieve a long cycle with low overpotential for 1000 ​h at a current density of 1 ​mA ​cm−2. Furthermore, when the full battery was assembled with LiFePO4 and the discharge capacity could be maintained at 151 mAh g−1 after 400 cycles at 1 ​C. In addition, the full battery also showed good rate performance, and provided a high discharge capacity of 114 mAh g−1 at 5 ​C. [Display omitted] •A Li3N film modified separator is prepared by PVD for the first time.•The Li3N/GO/PP separator show excellent thermal stability and electrolyte wettability.•With the Li3N/GO/PP separator, the overpotential of Li/Li symmetrical cell is kept below 50 ​mV.