Journal of Energy Chemistry ›› 2023, Vol. 79 ›› Issue (4): 272-278.DOI: 10.1016/j.jechem.2023.01.007

Previous Articles     Next Articles

In situ formed LiF-Li3N interface layer enables ultra-stable sulfide electrolyte-based all-solid-state lithium batteries

Ming Wua,b, Mengqi Lib, Yuming Jinb, Xinshuang Changb, Xiaolei Zhaob, Zhi Gub, Gaozhan Liub,*, Xiayin Yaob,c,*   

  1. aSchool of Material Science and Chemical Engineering, Ningbo University, Ningbo 315211, Zhejiang, China;
    bNingbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, Zhejiang, China;
    cCenter of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
  • Received:2022-11-27 Revised:2022-12-25 Accepted:2023-01-09 Online:2023-04-15 Published:2023-05-30
  • Contact: * E-mail addresses: liugaozhan@nimte.ac.cn (G. Liu), yaoxy@nimte.ac.cn (X. Yao).

Abstract: Sulfide solid electrolytes are promising for high energy density and safety in all-solid-state batteries due to their high ionic conductivity and good mechanical properties. However, the application of sulfide solid electrolytes in all-solid-state batteries with lithium anode is restricted by the side reactions at lithium/ electrolytes interfaces and the growth of lithium dendrite caused by nonuniform lithium deposition. Herein, a homogeneous LiF-Li3N composite protective layer is in situ formed via a manipulated reaction of pentafluorobenzamide with Li metal. The LiF-Li3N layer with both high interfacial energy and interfa-cial adhesion energy can synergistically suppress side reactions and inhibit the growth of lithium den-drite, achieving uniform deposition of lithium. The critical current densities of Li10GeP2S12 and Li6PS5Cl are increased to 3.25 and 1.25 mA cm-2 with Li@LiF-Li3N layer, which are almost triple and twice as those of Li-symmetric cells in the absence of protection layer, respectively. Moreover, the Li@LiF-Li3N/ Li10GeP2S12/Li@LiF-Li3N cell can stably cycle for 9000 h at 0.1 mA cm-2 under 0.1 mA h cm-2, and Li@LiF-Li3N/Li6PS5Cl/Li@LiF-Li3N cell achieves stable Li plating/stripping for 8000 h at 0.1 mA cm-2 under 10 mA h cm-2. The improved dynamic stability of lithium plating/stripping in Li@LiF-Li3N/Li10GeP2S12 or Li6PS5Cl interfaces is proved by three-electrode cells. As a result, LiCoO2/electrolytes/Li@LiF-Li3N batteries with Li10GeP2S12 and Li6PS5Cl exhibit remarkable cycling stability of 500 cycles with capacity retentions of 93.5% and 89.2% at 1 C, respectively.

Key words: LiF-Li3N, Sulfide solid electrolytes, Interface modification, High interface energy, All-solid-state batteries