Study On The Performance Of Electrolyte And Ni-samaria-doped Ceria Anode In IT-SOFC Base On Natural Gas

The fuel cell is an electrochemical generator with high efficiency and low pollution. It possesses several distinct advantages, such as environmental friendship, higher conversion efficiency and broad adaptive fuel. A solid oxide fuel cell (SOFC) is the third generation fuel cell, and all the components in SOFC are solid. So it has many advantages, such as no problem of corrosion and leakage, long life time quickly start-up and so on. It is imputed as the new green energy of the 21 century.The conventional SOFC based on H2 has some problems. First , It must operate at high temperature. So it require grindingly to its element. It is difficulty to seal up and has high cost. Second YSZ has low ionic conductivity at lower operating temperatures. Third H2 is difficult to store and transit compared to natural and biology gas。Recently, the IT-SOFC based on natural gas is submitted to solve these questions. In this paper, anode-supported solid state fuel cells (SOFCs) based on doped Ce0.8M0.2O1.9 (M = Y,Gd,Sm,La) and doped BaCe0.8M0.2O2.9 (M = Y,Gd,Sm,La) are fabricated by dry-pressing process, composite cathode consisting of 85wt%LSCF(La0.9Sr0.1Co0.2Fe0.8O3-δ)+15wt%GDC(Ce0.8Gd0.2O2-δ). These cells are tested form 400℃-600℃based on natural gas. Results show that 50wt% NiO/SDC anode,doped Ce0.8M0.2O1.9 (M = Y,Gd,Sm,La) and doped BaCe0.8M0.2O2.9 (M = Y,Gd,Sm,La) has homeosemy coefficient of thermal expansion. There are easy fritting. When dry natural gas is used as fuel, each cell has better performances. Along with temperature rising, gradually ,open circuit voltage bring down,current density and power density rise. When we use doped Ce0.8M0.2O1.9 (M = Y,Gd,Sm,La) as electrolytes , the maximum power density of each cell are 54.93mW/cm-2,59.50 mW/cm-2,45.33 mW/cm-2,37.75 mW/cm-2 at 600℃. When we use doped BaCe0.8M0.2O2.9 (M = Y,Gd,Sm,La) as electrolytes, The cell which use BaCe0.8Gd0.2O2.9 as electrolyte has the best performance. the maximum power density of this cell is 49.41mW/cm2. The double-deck anode cell (30wt%-60wt%)Ni-SDC/BCY2/LSCF-GDC) has better performance than single-deck anode cell (50wt%)Ni-SDC/BCY/LSCF-GDC). The power density of them are 34 mW/cm2 and 55 mW/cm2. some hydrone saturated hydrocarbon in natural gas converse to ethylene during the cell charging.Through improving making methodology and seal straight, the cell will have better performance.