Graduation Semester and Year
Fall 2025
Language
English
Document Type
Dissertation
Degree Name
Doctor of Philosophy in Materials Science and Engineering
Department
Materials Science and Engineering
First Advisor
Dr. Ye Cao
Second Advisor
Dr. Yaowu Hao
Third Advisor
Dr. Seong Jin Koh
Fourth Advisor
Dr. Kyung Suk Yum
Fifth Advisor
Dr. Qiming Zhang
Abstract
Metallic anodes, such as Lithium (Li) and Zinc (Zn), offer promise for the development of high-capacity rechargeable batteries. However, metallic anode-based batteries suffer from severe dendrite growth during the plating process, which poses safety hazards and accelerates capacity degradation. Experimental studies suggest that using a protective coating on the anode surface could potentially mitigate dendrite growth and prolong the battery’s life. However, there are limited theoretical studies on the inhibition effect of a protective layer on dendrite growth. Herein, we developed a phase-field model to simulate the impact of a protective layer on the plating and stripping cycle for Li and Zn anodes. Our results demonstrate that the protective layer physically blocks dendrite growth, reduces large concentrations and potential gradient on the anode surface, and prevents dead Li formation. Moreover, anisotropic diffusion of metallic ions in the protective layer significantly affects dendrite growth. It was found that higher diffusivity along the x-axis (perpendicular to the anode surface) inhibits dendrite growth, whereas higher diffusivity along the y-axis (parallel to the anode surface) promotes dendrite growth.
Solid electrolyte-based batteries offer significant benefits over liquid-electrolyte-based batteries, including higher energy density, enhanced safety, reduced dendrite formation, and being non-toxic to the environment. Nonetheless, solid electrolyte materials often contain some defects such as cracks, pores, voids, and grain boundaries, which could adversely affect Li deposition. These defects could facilitate dendrite growth, leading to short-circuiting in the battery. In solid electrolytes with grain boundaries (GBs), our study found that Li preferentially grows into GBs due to their lower mechanical stiffness compared to the bulk grain, resulting in inhomogeneous Li deposition. Similarly, voids on the Li anode grow faster if the applied current density is higher. However, void growth was significantly suppressed by applying stack pressure on the battery. Furthermore, in porous LLZO electrolytes, smaller pores result in homogenous Li deposition when compared to larger pores, which is attributed to the reduced local current density resulting from larger Li/electrolyte interfacial area. These results provide valuable insights for designing and selecting solid electrolyte materials for the safety and longevity of batteries.
Keywords
protective layer, dendrite growth, Li metal batteries, Zn metal batteries, void growth, solid-electrolytes, dead Li
Disciplines
Other Materials Science and Engineering
License
This work is licensed under a Creative Commons Attribution 4.0 International License.
Recommended Citation
Pant, Bharat R., "PHASE-FIELD MODELING OF A PROTECTIVE LAYER FOR THE SUPPRESSION OF DENDRITES IN METALLIC ANODE-BASED RECHARGEABLE BATTERIES" (2025). Material Science and Engineering Dissertations. 130.
https://mavmatrix.uta.edu/materialscieng_dissertations/130