Measuring Conductivities of Highly Conductive Membranes
Abstract
The theoretical and experimental aspects of an electrochemical approach for evaluating the conductivities of highly conductive membranes are described. The methods developed involve either a current or a potential step at a solid state electrochemical cell. It is assumed, and we prove, that only capacitive currents flow during these current or potential step experiments. The theory for these methods is derived from classical electrochemical theory for current and potential steps at RC circuits. We show that if the conductivity of the system under study is not too high (less than ca. 0.2/ohm/m), the classical theory provides accurate conductivity data. However, we also show that if the conductivity of the system is greater than ca. 0.2/ohm/m, conductivities obtained from the classical expressions are inaccurate. The modified theoretical analysis developed here, however, yields very accurate conductivity data for such highly conductive systems. The modifications of the classical theory entails accounting for the non-ideal wave shape of real potential or current step waveforms. Keywords: Conductive membranes, Electrochemical cell, Capacitive currents.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 28, 1989
- Accession Number
- ADA206043
Entities
People
- Chao Liu
- Charles R. Martin
- Zhihua Cai
Organizations
- Texas A&M University