Do Poly(Ethylene Oxide) Chains Orient during Electrochemical Polarization?

Based on several recent studies, we formulate the hypothesis of polymer chain alignment in LiTFSI/PEO electrolytes upon electrochemical cell polarization. Possible implications include ion transport parameters and an interpretation of nonlinear effects in electrophoretic nuclear magnetic resonance. We tested our hypothesis by operando wide-angle X-ray scattering and an analysis of the data in the context of Hermans’ orientation function. Our results show that cell polarization does not induce significant polymer chain alignment, indicating that LiTFSI/PEO electrolytes maintain their equilibrium structure upon polarization. Therefore, our work validates current approaches to electrolyte transport modeling.