Mechanism of Ion Transport in Solid Polymer Composite Electrolytes

Slow ion transport at ambient temperature impedes the practical use of solid polymer composite electrolytes (PCE). The underlying mechanism for the ionic conductivity are elucidated diversely, such as poor percolation network of fillers and sluggish segmental motions of the polymer. In this talk, we demonstrate that the polymer-ceramic particle interfacial polarization and segmental motion are directly coupled, both quantitively determine ion transport in PCE. Moreover, two different mechanisms enhance ionic conductivity in PCE, by either increasing concentration of ions participated transport or by increasing ion mobility. Accordingly, an ionic conductivity of 1.3 × 10^-3 S/cm in PCE can be achieved at 30 °C.