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DOE OSTI · 1466598

How Water Accelerates Bivalent Ion Diffusion at the Electrolyte/Electrode Interface

Wang, Fei·Sun, Wei·Shadike, Zulipiya·Hu, Enyuan·Ji, Xiao·Gao, Tao·Yang, Xiao-Qing·Xu, Kang·Wang, Chunsheng
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Abstract

The effect of H 2 O in electrolytes and in electrode lattices on the thermodynamics and kinetics of reversible multivalent-ion intercalation chemistry based on a model platform of layered VOPO 4 has been investigated. The presence of H 2 O at the electrolyte/electrode interface plays a key role in assisting Zn 2+ diffusion from electrolyte to the surface, while H 2 O in the lattice structure alters the working potential. More importantly, a dynamic equilibrium between bulk electrode and electrolyte is eventually reached for H 2 O transport during the charge/discharge cycles, with the water activity serving as the key parameter determining the direction of water movement and the cycling stability.

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25 ENERGY STORAGEbatterieselectrochemistryelectrolyteskineticswater

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Wang, Fei, Sun, Wei, Shadike, Zulipiya, Hu, Enyuan, Ji, Xiao, Gao, Tao, Yang, Xiao-Qing, Xu, Kang, Wang, Chunsheng. 2018-08-20. How Water Accelerates Bivalent Ion Diffusion at the Electrolyte/Electrode Interface. https://doi.org/10.1002/anie.201806748

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