Design of advanced electrolytes for targeted applications, including fast charging
We design and develop novel electrolytes that enable faster and more efficient ion transport for advanced battery technologies. Aforementioned electrophoretic NMR techniques enable direct measurement of critical parameters like cationic transference numbers, which are notoriously difficult to assess by other methods. These measurements provide valuable insights into how electrolytes perform under non-equilibrium conditions such as experienced during rapid charging of devices. Through the development, testing, and screening of novel electrolyte compositions, we can identify the formulations most likely to overcome specific challenges. These efforts are key to developing batteries with enhanced electrochemical performance, reduced concentration gradients, and minimized degradation, which are important criteria for both grid-scale energy storage and electric vehicle applications.
Linking local solvation structures, ion transport, and bulk electrochemical properties
A fundamental understanding of transport properties within electrolytes is possible by considering the connection to local ionic solvation structures. By leveraging advanced NMR techniques across multiple nuclei, including 7Li, 19F, and 1H, we can explore how spectra measured as a function of salt concentration and temperature act as sensitive reporters of solvation structure and ion dynamics. These spectroscopic data provide insights into the lifetimes of specific speciation states, shedding light on how solvation shell dynamics influence ion transport and bulk electrochemical performance. Additionally, we incorporate density functional theory (DFT) calculations to validate and quantitatively confirm the conclusions drawn from NMR. To extend the relevance of our findings, we collaborate with researchers who develop multi-scale models, linking local structural and transport information with predictions of electrolyte performance under real-world operating conditions. This joint approach helps guide the design of next-generation electrolytes with improved performance characteristics.
Development of novel magnetic resonance techniques for measuring ion dynamics in functioning devices
Our research focuses on pioneering advanced nuclear magnetic resonance (NMR) techniques that directly measure ion and solvent dynamics within functioning energy storage devices. Traditional methods, such as pulsed field gradient (PFG) NMR, are useful for measuring diffusion but cannot capture directional ion motion under the influence of an electric field. To address this, we are developing and advancing electrophoretic NMR, a technique that directly measures ion velocities. By extending electrophoretic NMR to enable spatiotemporal measurements under real operating conditions, we aim to study devices in situ and in operando within the NMR spectrometer.
By mapping how ion transport behaves across various parts of these systems under electrochemical conditions, we aim to provide deeper insights into performance limitations, particularly for fast-charging applications. These new methodologies offer unprecedented views of ion movement, laying a methodological foundation for improvements to high-performance battery technologies.
