EPSCoR Research Fellows: NSF: Developing A Coupled Multi-Energy-Scale Spectroscopic and Microscopic Analytical Approach for Halide-based Solid-State Batteries

Solid-state batteries (SSBs) have been widely considered as the hope to eliminate the safety issues of flammable liquid electrolyte-based counterparts. Despite such a decisive advantage, realizing a functional and efficient SSB has been greatly hindered by limited understanding of unwanted physical changes and chemical reactions at the solid electrode-solid electrolyte interface.

Such limited understanding is rooted in the lack of an analytical technique that can pinpoint the undesired physicochemical processes, disentangle the relationship of each process, and reveal the role of each process in battery performance. The project will realize a coupled multi-energy micro-spectroscopic analytical approach based on halide-based solid-state batteries, by incorporating different schemes of light-matter interactions and machine-learning-based analysis to reveal the nature of the interface of interest.

The project will drive concerted research efforts along multiple cutting-edge directions at the University of New Mexico, a Hispanic-Serving Institution, and profoundly diversify the research profile of the university. In a broader scope, the method and results of the Fellowship project will contribute to the STEM education of various disciplines by connecting fundamental principles and data-driven problem-solving, thus promoting young generations to make more impactful innovations.

This Research Infrastructure Improvement EPSCoR Research Fellows project will provide a fellowship to an Assistant Professor and training for a graduate student at the University of New Mexico. This work will be conducted in collaboration with researchers at the University of Texas at Austin. The objective of the Fellowship is to develop a coupled multi-energy-scale micro-spectroscopic analytical approach, to fundamentally understand the nature of entangled microstructural and chemical properties of Li|solid-state electrolyte (SSE) interface in halide-based SSBs.

The fellowship will integrate the bright field microscopic imaging, micro-Raman mapping, photoluminescence imaging, and X-ray tomography to quantitatively survey the Li|halide-SSE interface. Moreover, the project will employ machine-learning-based data-driven analysis to extract the correlation between microstructural & chemical features and to unravel the contribution of each deconvoluted feature in electrochemical behavior of the SSB.

The combination of the multi-modal micro-spectroscopic technique and the data-driven analysis will serve as a new multi-disciplinary experiment and data analysis platform that will make a strong impact, not only on the field of SSB development, but also on other materials systems that involve complex physicochemical processes. The project will make a valuable contribution in enriching textbook materials of important fundamental courses such as Analytical Chemistry, Instrumental Analysis, and Probability and Statistics, and forge more connection between these classroom knowledge and realistic research.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.