Fig. 1

Schematic illustration of working principle for DC-SOFC

Fig. 2

Equilibrium gas composition for a system of excessive carbon and oxygen based on thermodynamic calculation

Tab. 1

Selected standard thermodynamic data (under 100 kPa) for complete oxidation of carbon

Fig. 3

Effect of anode-to-carbon distance, D, on the output performance of a DC-SOFC operated at 850 oC: (A) Current density vs. voltage; (B) Power density vs. voltage[34].

Fig. 4

Schematic illustration of testing setup in a tubular DC-SOFC[36]

Fig. 5

A Ni-YSZ anode-supported cone-shaped DC-SOFC (A) and its output performance at 850 oC (B)[42]

Fig. 6

Ohmic resistance as a function of temperature during starting operation of a Ni-based anode-supported DC-SOFC[43]

Fig. 7

A 3-cell-stack of anode-supported cone-shaped DC-SOFC (A) and its output performances at different temperatures (B)[42]

Fig. 8

Schematic illustrations of a 3-cell-stack DC-SOFC with carbon loaded inside (A) and outside (B) of the tubular cells[58]

Fig. 9

Output performances (A) and discharging characteristics under a constant current of 1 A (B) for 3-cell-stacks of DC-SOFC with carbon loaded inside and outside the tubular cells[58]

Fig. 10

A DC-SOFC stacks based on a single electrolyte plate: (A) Multiple cells electrically connected in series through punched holes on the electrolyte; (B) A stack plate covering a container loaded with carbon fuel; (C) A stack formed by proper sealing[60]

Fig. 11

Output performances of a 4-cell-stack DC-SOFC based on a single electrolyte plate operated at a variety of temperatures (A) and discharging characteristics at a constant current of 200 mA and 800 oC (B)[60]

Fig. 12

Performances of DC-SOFC with various carbon fuels: char derived from leaves of orchard tree, activated carbon loaded with Fe as a catalyst, carbon mechanically prepared with a simulated composition of the leaf char, and activated carbon without any catalyst[61]

Fig. 13

Composition of minerals from wheat straw, corncob and bagasse[66]

Fig. 14

Output performances (A) and discharging characteristics at a constant current density of 140 mA·cm-2 (B) for DC-SOFC operated at 800 oC, with fuels of biochars derived from wheat straw, corncob and bagasse[66]

Fig. 15

Microstructure of biochar derived from coconut shell (A) and performance comparison for DC-SOFC operated with coconut shell char and activated carbon (B)[67]

Fig. 16

A DC-SOFC set for gas-electricity cogeneration (A) and output power and produced gas composition at different operating currents and 800 oC (B)[70]

Fig. 17

A schematic illustration of a tubular 2-cell-stack DC-SOFC (A) and its output power and produced gas composition at 800 oC (B)[70]