Increasing Power Density of LSGM-Based Solid Oxide Fuel Cells Using New Anode Materials

Chemical reactions between the superior perovskite oxide-ion conductor Sr- and Mg-doped LaGaO 3 (LSGM), CeO 2 , and NiO have been studied by powder X-ray diffraction. The results showed that an extensive reactivity occurs as a result of La migration driven by a gradient of La chemical activity. La migration across the LSGM/electrode interfaces in a fuel cell leads to the formation of resistive phases at the interface, either LaSrGa 3 O 7 or LaSrGaO 4 . Use of 40 mol % La 2 O 3 -doped CeO 2 as an interlayer between anode and electrolyte as well as in the NiO-containing anode prevents all reactions found. Consequently, the air-H 2 cell maximum power density was increased to nearly 900 mW/cm 2 at 800°C with a 600 μm thick LSGM electrolyte. No sign of degradation was observed at 800°C over 2 weeks for an interlayered cell under a loading current density of 250 mA/cm 2 .

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