Solid Oxide Fuel Cells (SOFC) Flashcards
Pros and Cons of high-T ceramic FC concepts
Advantages:
1. Improved reaction kinetics (they can work at higher T and therefore they have better ion conductivity)
2. Water management facilitated
3. Fuel flexibility
Disadvantages:
1. Performance
2. Corrosion
3. Slower load response
SOFC reactions
Cathode: O2 + 4e- → 2O(2-)
Anode: H2 + O(2-) → H2O + 2e-
Overall: 2H2 + O2 → 2H2O
SOFC - Cell Structure and Components
Presentation 2 Slide 26
–> Also empty drawing in the folder
SOFC - different cell designs.
What you achieve with the thickness of the layers, and different generations (draws of them)
Layers thin: You optimize weight and conductivity
Layers thick: You optimize mechanical support
1st generation: Electrolyte supported (lowest performance, highest maturity)
2nd generation: Cathode supported
2nd generation anode supported
3rd generation: externally supported (best performance, worst maturity)
Draws of all of them in Presentation 2 Slide 27
Define ceramic
Advantages and disadvantages?
Ceramic: Rigid material that consists of an infinite three-dimensional network of sintered crystalline grains comprising metals bonded to carbon, nitrogen or oxygen.
Advantages: Prevents gas cross-over, corrosion stability
Disadvantages: Require high temperatures for ion mobility
Principal material of the Anodes in SOFC?
Nickel (Ni)
Extrernal support - 3rd generation cells
characteristics of each materials
- Metal type:
- Requires lower operating T
- Thermal corrosion
- Materials: Ni, Stainless steel
- Ceramic type:
- Easy integration (similar expansion coefficient)
Cell Layouts - Know the draw of all of them, and table of characteristics
Cell Types table
Trade-Offs of Cercamic Fuel Cells in mobile applications
- High fuel efficiency
- Low stack specific power
- Less maturity
