Li-ion transference number (tLi+) of the ionomer electrolyte
was determined by using the steady-state current method [19],
on a coin cell assembled by sandwiching Al2O3-coated separator
between two Li foils. The method consists of initial measurement
of the lithium interfacial resistance (R0), then application
of a small voltage (DV, 10 mV) until a steady current (Iss) is
obtained, and final measurement of the interfacial resistance (Rf).
It is calculated using the equation tLi+ = (Iss(V - I0R0))/(I0(V -
IssRf)), where I0 is the initial current. The ionic conductivity of the
Al2O3-coated separator was evaluated via using electrochemical
impedance spectroscopy (EIS), on a cell assembled by sandwiching
a liquid electrolyte-soaked separator between two stainless-steels.
The ionic conductivity ofthe separator is calculated using the equation
= d/RbS, where d is the thickness of the separator, Rb is the
bulk resistance of the separator, and S is the area of the separators.
Allthe measurements here were conducted with Applied Princeton
Research Parstat 2273.