Unveiling the Mysteries: Acetonitrile's Dance with Weakly-Solvating Electrolytes in Shaping Gas Evolution and Electrochemical Performance of Zinc-ion Batteries
Journal article, 2024

Aqueous Zn-metal battery (AZMB) is a promising candidate for future large-scale energy storage with commendable capacity, exceptional safety characteristics, and low cost. Acetonitrile (AN) has been widely used as an effective electrolyte constituent to improve AZMBs’ performance. However, its functioning mechanisms remain unclear. In this study, we unveiled the critical roles of AN in AZMBs via comparative in situ electrochemical, gaseous, and morphological analyses. Despite its limited ability to solvate Zn ions, AN-modulated Zn-ion solvation sheath with increased anions and decreased water achieves a weakly-solvating electrolyte. As a result, the Zn||Zn cell with AN addition exhibited 63 times longer cycle life than cell without AN and achieved a 4 Ah cm−2 accumulated capacity with no H2 generation. In V2O5||Zn cells, for the first time, AN suppressing CO2 generation, elevating CO2-initiation voltage from 2→2.44 V (H2: 2.43→2.55 V) was discovered. AN-impeded transit and Zn-side deposition of dissolved vanadium ions, known as “crosstalk,” ameliorated inhomogeneous Zn deposition and dendritic Zn growth. At last, we demonstrated an AN-enabled high-areal-capacity AZMB (3.3 mAh cm−2) using high-mass-loading V2O5 cathode (26 mg cm−2). This study shed light on the strategy of constructing fast-desolvation electrolytes and offered insights for future electrolyte accommodation for high-voltage AZMB cathodes.

aqueous Zn-metal batteries

gas evolution suppression

Zn-dendrite mitigation

electrolyte additive

Zn metal anode

Vanadium dissolution alleviation

Author

Zhenrui Wu

University of British Columbia (UBC)

Yihu Li

Chalmers, Physics, Materials Physics

Amardeep Amardeep

University of British Columbia (UBC)

Yijia Shao

University of British Columbia (UBC)

Key Laboratory of Fuel Cell Technology of Guangdong Province

Yue Zhang

University of British Columbia (UBC)

Jian Zou

University of Electronic Science and Technology of China

Liping Wang

University of Electronic Science and Technology of China

Jia Xu

University of British Columbia (UBC)

Dawid Kasprzak

Poznan University of Technology

University of British Columbia (UBC)

Evan J. Hansen

University of British Columbia (UBC)

Jian Liu

University of British Columbia (UBC)

Angewandte Chemie

14337851 (ISSN) 15213773 (eISSN)

Vol. 63 19 e202402206

Areas of Advance

Energy

Materials Science

Subject Categories

Materials Chemistry

Other Physics Topics

DOI

10.1002/anie.202402206

PubMed

38457347

More information

Latest update

5/4/2024 4