Fuel Cell Connections
1st method — edge connection
connect
edges of each anode to the cathode of the next cell
Problem: electrons
must flow across the face of the electrode to the current connection point at
the edge
- produces a voltage drop
2nd
method — bipolar
plate
Makes
connections all over one cathode and the anode of the next cell
Bipolar Plate Design
Feeds
oxygen to the cathode and fuel to the anode
- Two gas supplies must be strictly separated
Good electrical connections must be made between
the two electrodes
Design Conflicts:
- Contact points should be large
- Gas flow over electrodes should be high
- Electrical resistance should be minimized (thin plate)
Graphite is common material for plate
Machining is expensive
- Plate is significant cost factor
Modern
Bipolar Plate
