Unraveling the Role of Cation Solvation in Aqueous Zn-Ion Batteries- A Combined Theoretical and Experimental Approach
Abstract
Rechargeable aqueous Zn-ion batteries (RAZIBs) have emerged as a promising technology for stationary energy storage due to their high safety, low cost, high capacity, and long cycle life. However, RAZIBs are currently facing critical technical challenges toward commercialization such as limited cycle life, particularly at low cycle rate. There is growing evidence that this performance degradation is deeply rooted in the interactions between the aqueous electrolytes and electrodes and the subsequent formation of inert interfacial products (aka. solid electrolyte interphase or SEI). Unfortunately, a thorough understanding of the degradation mechanisms and knowledge of key performance descriptors are still lacking. To address these gaps, we propose a combined computational and experimental approach to investigate the degradation mechanisms in various RAZIB electrolytes with different solvation shell structures under different electric field conditions. We will use machine learning potentials trained to ab initio molecular dynamics simulations to generate system-specific solvent models for the three commonly used Zn-salt electrolytes. The simulations will assist in identifying the key factors that affect the charge transfer processes and passivation layer formation, which are often difficult to determine experimentally. The computational findings will be verified through extensive experimental measurements of the physical, chemical, and electrochemical properties of the electrolytes, creating a closed loop of experiment-model investigation. Our research will lead to a deeper understanding of the critical role of cation solvation in passivation layer formation and degradation mechanisms in RAZIBs, providing insights for future electrolyte engineering efforts to enhance RAZIBs commercialization.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Mar 06, 2024
- Source ID
- FA95502310505
Entities
People
- Christopher D. Sutton
Organizations
- Air Force Office of Scientific Research
- Office of the Secretary of Defense
- University of South Carolina