Proton Exchange Membrane (PEM)
The heart of the fuel cell is referred to as the Stack, and is where the electrochemical reaction occurs in order to produce electricity. The stack is made from an array of individual cells, each separated by bipolar plates. The individual cell contains a crucial set of elements called the Membrane Electrode Assembly (MEA). The MEA is made from a polymeric Proton Exchange Membrane (PEM) whose surfaces are coated on both sides with a catalyst.
Aquivion® PFSA, a special proton-conductive material available as a membrane or dispersion, is an excellent choice for the PEM thanks to:
- Very high concentration of functional groups for strong proton (or Na+, K+) conductivity
- High softening point for high-temperature operation above 80°C (176°F)
- Strong water retention, e.g. for a better low-humidity fuel cell operation
- Material stability for stable and extended operation, also above 100°C and below 50% rH
Various grades are tailored for the type of PEFC to be produced or the processes applied during MEA production.
Stack Sealing
Tecnoflon® FKM is the ideal material for fuel cell stack sealing with high softness thanks to its outstanding properties:
- Extreme chemical resistance
- High temperature rating (up to 250°C) – a mandatory choice where conventional rubbers reach their limits (temperature over 100-120°C)
- Low gas permeability
Where necessary, high purity fluoroelastomers (organic filled) are also available.
Materials
Aquivion® PFSA
Tecnoflon® FKM Low Temp
Tecnoflon® FKM Peroxide
Tecnoflon® FKM/FFKM PFR
