Lithiated Nafion 112 ionomer was characterized by FT-IR spectroscopy, AC impedance, and cyclic voltammetry. The ionomer swollen with mixed solvents of propylene carbonate (PC) and ethylene carbonate shows ionic conductivity of 8.18×10−5Scm−1 at 25°C and good electrochemical stability to allow operation in Li/ionomer/LiCoO2 cells. The discharge capacity of the first cycle is 126mAhg−1. Significant capacity loss occurs during cycling due to the presence of PC. AC impedance shows that the passive layer formed at the Li/ionomer interface dominates the cycling performance of the cell.
