Dynamics of Solid Polymer Electrolytes with High Dielectric Constants*

Solid polymer electrolytes (SPE) are next-generation electrolytes for rechargeable batteries, fuel cells, and desalination membranes. However, current SPEs suffer from low ionic conductivity due to a lack of understanding of the ion transfer in polymers. Through combining broadband dielectric spectroscopy (BDS) and rheology, the ion dynamics of lithium bis(trifluoromethane)sulfonimide (LiTFSI) salt-doped polyelectrolytes have been investigated, including poly(epichlorohydrin) (PECH), poly(propylene oxide) (PPO), and poly(butylene oxide) (PBO). While increasing dielectric constant of the polymer matrix increases the solvation of the ions, the ultimate ion dynamics have been strongly regulated by the dynamics of the matrix. The talk will also present the relationship between increasing polarity on conductivity, the relaxation time of the polymer, and ion transport of these SPEs of high dielectric constant.