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This portal page aggregates information relevant to High Temperature
PEM Fuel Cells including membranes, plates, stacks, systems, materials and components.
Why the need for High Temperature PEM Fuel Cell
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Stationary -
Click here for micro CHP products using HTEPM stacks.
- Tolerance to Impurities - High temperature
systems (above 120°C) have higher tolerances to impurities
(particularly CO) in the
hydrogen. The optimum tolerance to impurities is at temperatures
exceeding 150°C which is best suited to stationary systems. For
stationary applications (over 150°C) the CO tolerance would
eliminate some fuel processor
(reformer) components.
- Operating Temperature - Due to structural limitations
current water-based (low temperature PEM) membranes can only work up to 80°C.
HTPEM membranes have been demonstrated to operate up to 210°C. At the higher temperatures (over 150°C) the system takes longer to
start-up and is therefore suited to stationary applications.
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Automotive - Low temperature Fuel cell stacks operating at 80°C require large radiators/heat exchangers
to extract the heat. There are potential 50% reductions to radiator size using HTPEM.
-
Performance - Increasing the operating temperature
of the system increases the electrode kinetic rates which improves the
performance of the
fuel cell
- Water management – as high temperature membranes
are generally non-water based there is no need for humidification which reduces system complexity and cost.
Industry requirements
- Operating temperature
- Automotive - over 120°C
- Stationary - over 150°C
- Low cost
- High tolerance to impurities
- Durable
- Long term chemical and mechanical stability
- Low resistance
- Increased stability must not compromise conductivity
HTPEM membranes require less porous plates than low temperature PEM. This is due to acid leaching from the membrane, click here to view plates ideally suited to HTPEM
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