Novel electrolytes for solid oxide fuel cells with improved mechanical properties


TİMURKUTLUK B., Celik S., Timurkutluk C., Mat M. D., Kaplan Y.

INTERNATIONAL JOURNAL OF HYDROGEN ENERGY, vol.37, no.18, pp.13499-13509, 2012 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 37 Issue: 18
  • Publication Date: 2012
  • Doi Number: 10.1016/j.ijhydene.2012.06.103
  • Journal Name: INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.13499-13509
  • Keywords: Solid oxide fuel cell, Yttria stabilized zirconia, Novel electrolyte design, Finite element modeling, Tensile and bending strength, GADOLINIUM-DOPED CERIA, STABILIZED ZIRCONIA ELECTROLYTE, IONIC-CONDUCTIVITY, ELECTROCHEMICAL PROPERTIES, ELECTRICAL-CONDUCTIVITY, ANODE, SOFC, OXIDATION, CERAMICS, STRENGTH
  • Middle East Technical University Affiliated: No

Abstract

The improvement of the mechanical properties of novel structured electrolytes with triangular cut off geometry in the active region is presented by filleting the tips of triangles. The effect of fillet radius on the bending strength of the yttria stabilized zirconia electrolyte was investigated with a commercial finite element code implementing the calculated Weibull stress through the experimental stress strain curve determined via tensile tests. The model was verified with the experimental three point bending test results for the electrolyte with unfilleted triangular cut off patterns. Ten different fillet radii ranging from 0.05 mm to 0.5 mm were considered in the simulations. The fracture displacement was found to increase with increasing fillet radius as expected. Since the electrolyte with fillet radius of 0.5 mm was found to show the highest flexural strength, single cell based on this electrolyte was fabricated and the cell performance was measured. It was found that the strength of the novel electrolyte with partly reduced thickness can be increased by 26.2% with sacrificing only 10.2% decrease in the performance. Since the final cell still showed 22.2% higher peak performance than the standard electrolyte supported cell, 10.2% decrease in the cell performance compared to the cell having unfilleted triangular cut off patterns is acceptable. Copyright (C) 2012, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.