A polyacrylonitrile-based gelled electrolyte: electrochemical kinetic studies

Abstract

The bulk and interfacial properties of thin films of a polyacrylonitrile-based (PAN-based) gelled electrolyte, which was tested in conjunction with lithium electrodes, were evaluated at room temperature. The typical composition of the gelled electrolyte (GE) studied was PAN (9.13 wt %); propylene carbonate, or PC (84.87 wt %); and LiBF4 (6 wt %). A.c. and d.c. measurements were used to determine the bulk conductivity and the interfacial apparent charge-transfer resistance (Ract) of the GE. While the bulk conductivity remains stable at around 10−3 S cm−1, the Ract varies initially before reaching a steady value. The steady Ract value obtained from the electrochemical measurements is near 1000 ω cm2. The plating/stripping efficiency of lithium, from potentiostatic and galvanostatic measurements, is 70 to 80%.