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Title: Phase-Field Simulation of a Dynamic Protective Layer for the Inhibition of Dendrite Growth in Zinc Metal Batteries
Metallic zinc (Zn) has been considered one of the most promising anode materials for next-generation aqueous Zn batteries due to its low redox potential and high storage capacity. However, excessive dendrite formation in Zn metal, corrosion, the evolution of hydrogen gas during the cycling process, and the poor Zn-ions (Zn2+) transport from the electrolyte to the electrode limits its practical application. One of the most effective strategies to suppress Zn dendrite growth and promote Zn2+ transport is to introduce suitable protective layers between the Zn metal electrode and the electrolyte. Herein, we mathematically simulated the dynamic interactions between the Zn deposition on the anode and the resulting displacement of a protective layer that covers the anode, the latter of which can simultaneously inhibit Zn dendrite growth and enhance the Zn2+ transport through the interface between Zn anode and the protective layer. Our simulation results indicate that a protective layer of high Zn2+ diffusivity not only improves the deposition rate of the Zn metal but also prevents the dendrite growth by homogenizing the Zn2+ concentration at the anode surface. In addition, it is revealed that the anisotropic Zn2+ diffusivity in the protective layer influences the 2D diffusion of Zn2+. Higher Zn2+ diffusivity perpendicular to the Zn metal surface inhibits the dendrite growth, while higher diffusivity parallel to the Zn metal surface promotes dendrite growth. Our work thus provides a fundamental understanding and a design principle of controlling anisotropic Zn2+ diffusion in the protective layer for better suppression of dendrite growth in Zn metal batteries.  more » « less
Award ID(s):
2038083
NSF-PAR ID:
10491282
Author(s) / Creator(s):
; ;
Publisher / Repository:
American Chemical Society
Date Published:
Journal Name:
ACS Applied Materials & Interfaces
Volume:
15
Issue:
51
ISSN:
1944-8244
Page Range / eLocation ID:
59329 to 59336
Subject(s) / Keyword(s):
["phase-field simulation, zinc metal battery, dendrites growth, anisotropic diffusion, protective layer"]
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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    Acknowledgment

    This work was partially supported by the U.S. National Science Foundation (NSF) Award No. ECCS-1931088. S.L. and H.W.S. acknowledge the support from the Improvement of Measurement Standards and Technology for Mechanical Metrology (Grant No. 22011044) by KRISS.

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