Ion–Solvent Complexes Promote Gas Evolution from Electrolytes on a Sodium Metal Anode

Xiang Chen, Xin Shen, Bo Li, Hong Jie Peng, Xin Bing Cheng, Bo Quan Li, Xue Qiang Zhang, Jia Qi Huang, Qiang Zhang*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

219 Citations (Scopus)

Abstract

Lithium and sodium metal batteries are considered as promising next-generation energy storage devices due to their ultrahigh energy densities. The high reactivity of alkali metal toward organic solvents and salts results in side reactions, which further lead to undesirable electrolyte depletion, cell failure, and evolution of flammable gas. Herein, first-principles calculations and in situ optical microscopy are used to study the mechanism of organic electrolyte decomposition and gas evolution on a sodium metal anode. Once complexed with sodium ions, solvent molecules show a reduced LUMO, which facilitates the electrolyte decomposition and gas evolution. Such a general mechanism is also applicable to lithium and other metal anodes. We uncover the critical role of ion–solvent complexation for the stability of alkali metal anodes, reveal the mechanism of electrolyte gassing, and provide a mechanistic guidance to electrolyte and lithium/sodium anode design for safe rechargeable batteries.

Original languageEnglish
Pages (from-to)734-737
Number of pages4
JournalAngewandte Chemie - International Edition
Volume57
Issue number3
DOIs
Publication statusPublished - 15 Jan 2018

Keywords

  • alkali metal batteries
  • electrochemistry
  • electrolytes
  • first-principles calculations
  • gas evolution

Fingerprint

Dive into the research topics of 'Ion–Solvent Complexes Promote Gas Evolution from Electrolytes on a Sodium Metal Anode'. Together they form a unique fingerprint.

Cite this