Manipulating anion intercalation enables a high-voltage aqueous dual ion battery

Zhaodong Huang; Yue Hou; Tairan Wang; Yuwei Zhao; Guojin Liang; Xinliang Li; Ying Guo; Qi Yang; Ze Chen; Qing Li; Longtao Ma; Jun Fan; Chunyi Zhi

doi:10.1038/s41467-021-23369-5

Manipulating anion intercalation enables a high-voltage aqueous dual ion battery

Nat Commun. 2021 May 25;12(1):3106. doi: 10.1038/s41467-021-23369-5.

Authors

Zhaodong Huang¹, Yue Hou¹, Tairan Wang¹, Yuwei Zhao¹, Guojin Liang¹, Xinliang Li¹, Ying Guo¹, Qi Yang¹, Ze Chen¹, Qing Li¹, Longtao Ma¹, Jun Fan², Chunyi Zhi³

Affiliations

¹ Department of Materials Science and Engineering, City University of Hong Kong, Kowloon, Hong Kong, China.
² Department of Materials Science and Engineering, City University of Hong Kong, Kowloon, Hong Kong, China. junfan@cityu.edu.hk.
³ Department of Materials Science and Engineering, City University of Hong Kong, Kowloon, Hong Kong, China. cy.zhi@cityu.edu.hk.

Abstract

Aqueous graphite-based dual ion batteries have unique superiorities in stationary energy storage systems due to their non-transition metal configuration and safety properties. However, there is an absence of thorough study of the interactions between anions and water molecules and between anions and electrode materials, which is essential to achieve high output voltage. Here we reveal the four-stage intercalation process and energy conversion in a graphite cathode of anions with different configurations. The difference between the intercalation energy and hydration energy of bis(trifluoromethane)sulfonimide makes the best use of the electrochemical stability window of its electrolyte and delivers a high intercalation potential, while BF₄^- and CF₃SO₃^- do not exhibit a satisfactory potential because the graphite intercalation potential of BF₄^- is inferior and the graphite intercalation potential of CF₃SO₃^- exceeds the voltage window of its electrolyte. An aqueous dual ion battery based on the intercalation behaviors of bis(trifluoromethane)sulfonimide anions into a graphite cathode exhibits a high voltage of 2.2 V together with a specific energy of 242.74 Wh kg^-1. This work provides clear guidance for the voltage plateau manipulation of anion intercalation into two-dimensional materials.