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Development of a Silver Based Stable Current Collector for Solid Oxide Fuel Cell Cathodes Ayhan Sarikaya, Vladimir Petrovsky and Fatih Dogan Department of Materials Science and Engineering, Missouri University of Science and Technology, Rolla, MO 65409, U.S.A. ABSTRACT Long term stability has been a crucial issue for the future applications of the solid oxide fuel cells (SOFCs). Current collectors for the cathodes have been among the most vulnerable components of the SOFCs due to their operation in oxidizing atmospheres at relatively high temperatures. Ag and Ag based LSM (lanthanum-strontium manganite) composites were studied to develop highly stable and low-cost current collectors compatible with other fuel cell components. In this study, no degradation was observed in the electrical conductivity and the porous microstructure of the Ag-LSM composite current collectors after 600 hours of operation at 800oC in air. INTRODUCTION Power loss due to high resistance of contact materials has been a fundamental concern for the development of solid oxide fuel cells (SOFCs) [1, 2]. Current collection on the cathode side is more challenging than the anode side especially for the intermediate temperature (600oC800oC) SOFCs due to high temperature oxidation [3-5]. Currently available current collectors include ceramics (e.g. LaCoO3 and LaCrO3) and noble metals (e.g. Pt, Pd, Au and Ag) [6]. Ceramic materials have high stability in oxidizing conditions; however, their electrical conductivity is limited. Although noble metals such as Pt, Au or Pd are known as current collectors stable at high temperatures, their relatively high cost makes them less desirable for use in SOFC applications [6-8]. Ag is a relatively inexpensive candidate with various attributes such as high conductivity, high ductility and self-healing at operating temperatures [7, 9]. However, its structural instability has limited its use in operational conditions of SOFCs [7, 9, 10, 11]. Since operational temperatures of SOFCs (e.g. 800oC) are fairly close to the melting temperature of pure Ag (962oC), sintering between Ag particles results in near complete densification of initially porous microstructure within a relatively short time (