Performance and endurance of a PEMFC operated with synthetic reformate fuel feed

Widespread implementation of polymer electrolyte membrane fuel cell (PEMFC) powerplants for stationary and vehicular applications will be dependent in the near future on using readily available hydrocarbon fuels as the source of the hydrogen fuel. Methane and propane are ideal fuels for stationary applications, while methanol, gasoline, and diesel fuel are better suited for vehicular applications. Various means of fuel processing are possible to produce a gaseous fuel containing H2, CO2 and CO. CO is a known electrocatalyst poison and must be reduced to low (10ʹs) ppm levels and CO2 is said to cause additional polarization effects. Even with no CO in the feed gas a H2/CO2/H2O gas mixture will form some CO. Therefore, as a first step of developing a PEMFC that can operate for thousands of hours using a reformed fuel, we used an anode gas feed of 80% H2 and 20% CO2 to simulate the reforming of CH4. To investigate the effect of reformate on cell performance and endurance, a single cell with an active area of 58 cm2 was assembled with a membrane electrode assembly (MEA) furnished by Texas A&M University using IGTʹs internally manifolded heat exchange (IMHEX™) design configuration. The MEA consisted of a Nafion 112 membrane with anode and cathode Pt catalyst loadings of 0.26 and 1.46 mg/cm2, respectively. The cell was set to operate on a synthetic reformate–air at 60°C and 1 atm and demonstrated over 5000 h of endurance with a decay rate of less than 1%/1000 h of operation. The cell also underwent four successful thermal cycles with no appreciable loss in performance. The stable performance is attributed to a combination of the IGT IMHEX plate design with its inherent uniform gas flow distribution across the entire active area and MEA quality. The effects of temperature, gas composition, fuel utilization (stoics) and thermal cycle on cell performance are described.