La 1.7 Ca 0.3 Ni 0.75 Cu 0.25 O 4-δ -Layered Perovskite as Cathode on La 0.9 Sr 0.1 Ga 0.8 Mg 0.2 O 3 or Ce 0.8 Gd 0.2 O 2 Electrolyte for Intermediate Temperature Solid Oxide Fuel Cells