Film percolation for composite electrodes of solid oxide fuel cells

2011 ◽  
Vol 56 (13) ◽  
pp. 4763-4769 ◽  
Author(s):  
Yanxiang Zhang ◽  
Changrong Xia
Keyword(s):  
Fuel Cells ◽  
Solid Oxide Fuel Cells ◽  
Solid Oxide ◽  
Oxide Fuel ◽  
Composite Electrodes

Effects of Mass Transport on the Performance of Solid Oxide Fuel Cells Composite Electrodes

2006 ◽  
Vol 4 (1) ◽  
pp. 99-106 ◽  
Author(s):  
Marco Cannarozzo ◽  
Simone Grosso ◽  
Gerry Agnew ◽  
Adriana Del Borghi ◽  
Paola Costamagna
Keyword(s):  
Fuel Cells ◽  
Mass Transport ◽  
Solid Oxide Fuel Cells ◽  
Gas Diffusion ◽  
Transport Equations ◽  
Solid Oxide ◽  
The Other ◽  
Oxide Fuel ◽  
Composite Electrodes ◽  
The Impact

Composite electrodes are of great interest in the field of solid oxide fuel cells because their use can improve the performance of these cells. However, an important correlation exists between composition, microstructure, and thickness of an electrode and its performance. This correlation has been investigated in this work using a theoretical model. The model, in order to consider all the losses occurring in an electrode, includes Ohm’s law for ionic and electronic charge transport, and the Butler-Volmer equation to evaluate the activation polarizations, and mass transport equations, taking into account diffusion through porous media, to evaluate the concentration losses. The model shows that the best electrode performance is a trade-off between activation and concentration losses. This is because a decrease in the dimensions of the particles or an increase in its thickness result, on the one hand, in a reduction of the activation polarizations, because of a larger active area for the electrochemical reaction, and, on the other hand, in an increase in the concentration losses due to a more difficult gas diffusion. In particular, in order to understand the impact of concentration losses on the performance of composite electrodes, the simulations have been run with two models, one including and the other one neglecting the mass transport equations. The results show that concentration losses play a role only with thick electrodes composed of small particles, operating at high fuel utilization.

Nano-film coated cathode functional layers towards high performance solid oxide fuel cells

2018 ◽  
Vol 6 (25) ◽  
pp. 11811-11818 ◽  
Author(s):  
Mingi Choi ◽  
Jongseo Lee ◽  
Wonyoung Lee
Keyword(s):  
Fuel Cells ◽  
Solid Oxide Fuel Cells ◽  
Oxygen Reduction Reaction ◽  
High Performance ◽  
Reduction Reaction ◽  
Solid Oxide ◽  
Oxide Fuel ◽  
Composite Electrodes ◽  
Phase Boundaries ◽  
Infiltration Process

Nano-structured composite electrodes, from a carefully conducted infiltration process, are one of the most promising electrode structures for intermediate temperature solid oxide fuel cells (IT-SOFCs), due to their ability to promote the oxygen reduction reaction (ORR) and enlarge triple phase boundaries (TPBs).

Effect of the Microstructure of Porous Composite Electrodes on the Electric Power Density of Solid Oxide Fuel Cells

2011 ◽  
Author(s):  
Siamak Farhad ◽  
Feridun Hamdullahpur
Keyword(s):  
Fuel Cells ◽  
Solid Oxide Fuel Cells ◽  
Electric Power ◽  
Power Density ◽  
Average Power ◽  
Solid Oxide ◽  
Oxide Fuel ◽  
Composite Electrodes ◽  
Porous Composite ◽  
Macro Model

The electric power density generated in co-flow planar solid oxide fuel cells (SOFCs) with porous composite electrodes is predicted using the cell combined micro- macro-model; and the effect of the microstructural variables of the electrodes on the cell power generation is studied. In the combined micro- macro-model, the electrochemical performance of the porous composite electrodes is determined from the micro-model and the distributions of the temperature in solid structure of the cell and the temperature and species partial pressures of the bulk fuel and air streams are determined from the cell macro-model. As a case study, the effect of the microstructural variables of the porous composite electrodes of the Ni-YSZ/YSZ/LSM-YSZ cell operated at the given voltage, fuel utilization ratio, and excess air, on the average power density of the cell is investigated through computer simulation. The results reveal that there is an optimum value for each microstructural variables of the electrodes at which the cell power density is maximized.

Sign in / Sign up

Export Citation Format

Share Document