Calculation of the oxygen potential profile across solid-state electrochemical cells

Singh, R and Jacob, KT (2003) Calculation of the oxygen potential profile across solid-state electrochemical cells. In: Journal of Applied Electrochemistry, 33 (7). pp. 571-576.

PDF fulltext.pdf Restricted to Registered users only Download (128kB) | Request a copy

Abstract

Although several methods of solving the charge and mass transport equations in solid electrolytes wired for device applications have been reported in the literature, there are several inconsistencies. Yuan and Pal have expressed some misgivings regarding the earlier treatment of Choudhury and Patterson. The recent analysis by Nafe is at variance with the analysis of Yuan and Pal. This paper presents a critical examination of various methods for solving transport equations in solid-state electrochemical devices based on mixed ionic-electronic conductors. A complete equivalence between the approaches of Yuan and Pal and Choudhury and Patterson is demonstrated. The oxygen chemical potential profiles generated by both models are identical for a variety of boundary conditions and circuit parameters for a typical cell configuration. The concept of 'fictitious conductivity' introduced by Nafe is found to be inappropriate. It implies linear variation of the electrochemical potential of electrons inside the electrolyte, which is not generally valid for a mixed conductor. The oxygen chemical potential profiles inside the electrolyte calculated using Nafe's equation for different conditions differ substantially from those predicted by the other models. The flawed theoretical formulation is responsible for this mismatch. The methods of Choudhury and Patterson, Riess, and Yuan and Pal are essentially equivalent.

Item Type:	Journal Article
Publication:	Journal of Applied Electrochemistry
Publisher:	Springer Netherlands
Additional Information:	The copyright of this article belongs to Springer Netherlands.
Keywords:	Oxygen;Charge transfer;Mass transfer;Solid electrolytes;Ionic conduction;Electrons;Boundary conditions;Transport equations
Department/Centre:	Division of Mechanical Sciences > Materials Engineering (formerly Metallurgy)
Date Deposited:	09 Feb 2007
Last Modified:	19 Sep 2010 04:34
URI:	http://eprints.iisc.ac.in/id/eprint/9703

Actions (login required)

View Item