Fluorine-Free Water-in-Salt Electrolyte for Green and Low-Cost Aqueous Sodium-Ion Batteries

Jin Han; Huang Zhang; Alberto Varzi; Stefano Passerini

doi:10.1002/cssc.201801930

Fluorine-Free Water-in-Salt Electrolyte for Green and Low-Cost Aqueous Sodium-Ion Batteries

ChemSusChem. 2018 Nov 9;11(21):3704-3707. doi: 10.1002/cssc.201801930. Epub 2018 Oct 11.

Authors

Jin Han^{1

2}, Huang Zhang^{1

2}, Alberto Varzi^{1

2}, Stefano Passerini^{1

2}

Affiliations

¹ Helmholtz Institute Ulm (HIU), Helmholtzstrasse 11, 89081, Ulm, Germany.
² Karlsruhe Institute of Technology (KIT), P.O. Box 3640, 76021, Karlsruhe, Germany.

PMID: 30222910
DOI: 10.1002/cssc.201801930

Abstract

The highly concentrated "water-in-salt" electrolyte (WiSE) containing sodium acetate and potassium acetate demonstrates surprising performance (specific capacity of 37 mA h^-1 g^-1 at the 5th cycle and average discharge voltage of 0.82 V) in aqueous sodium-ion batteries (SIBs) based on Na₂ MnFe(CN)₆ and NaTi₂ (PO₄ )₃ . The fluorine-free electrolyte offers a wide electrochemical stability window and compatibility with Al current collector. The electrolyte, current collector, and the electrode materials based on abundant elements make the proposed battery chemistry safe, low-cost, and environmentally friendly.

Keywords: aluminum; aqueous electrolyte; fluorine-free; sodium-ion battery; water-in-salt.

Abstract

Grants and funding