(128c) Single-Ion Conducting Polymer Electrolytes for Rechargeable Batteries

Electrochemical energy storage devices are increasingly desired for consumer vehicle electrification and renewable power utilization. Safety and performance of batteries is strongly dictated by the performance of the electrolyte. Polymer electrolytes offer advantages over liquid and inorganic solid-state electrolytes, as they are non-leakable and non-volatile, yet flexible. Single-ion conducting electrolytes that eliminate ion concentration gradients can offer further advantages: greater electrochemical stability allowing for higher voltage cells, lower interfacial impedance, and higher theoretical charge/discharge rates. Single-ion conducting polymer electrolytes may simply be created by titration of a polyanion with the active cation – Li+ in a Li-ion battery, for example. Improved understanding of cation transport mechanisms in single-ion conducting polymers is critical for the development of high performance electrolytes. This talk will highlight our efforts to understand ion states and ion transport in two distinct classes of single-ion conducting polymers. The first class of materials of interest are gel polymer electrolytes, where the research focus is to understand ion-pair dissociation and ion states that contribute to conduction. It is found that cation-polymer and solvent-polymer interactions have a strong influence on the ionic conductivity of single-ion conducting gel polymer electrolytes.¹ The second class of materials of interest is solid-state ionomers with solely non-polar polymer components, where we aim to understand ion transport in phase segregated ionic domains. We report on a new family of these solid-state electrolytes based on side-chain polyanions where it is found that the chemistry of the tethered anion has a strong impact on cation transport.²

1. H. O. Ford, B. Park, J. Jiang, M. E. Seidler, and J. L. Schaefer, “Enhanced Li+ conduction within single-ion conducting polymer gel electrolytes via reduced cation-polymer interaction,” ACS Materials Letters, 2, 272-279, 2020. https://doi.org/10.1021/acsmaterialslett.9b00510
2. J. Liu, P. D. Pickett, B. Park, S. Upadhyay, S. V. Orski, and J. L. Schaefer, “Non-solvating, side-chain polymer electrolytes as lithium single-ion conductors: synthesis and ion transport characterization,” Polymer Chemistry, 11, 461-471, 2020. https://doi.org/10.1039/C9PY01035A