Three-dimensional anode engineering for the direct methanol fuel cell

Catalyzed graphite felt three-dimensional anodes were investigated in direct methanol fuel cells (DMFCs) operated with sulfuric acid supporting electrolyte. With a conventional serpentine channel flow field the preferred anode thickness was 100 μm, while a novel flow-by anode showed the best performance with a thickness of 200–300 μm. The effects of altering the methanol concentration, anolyte flow rate and operating temperature on the fuel cell superficial power density were studied by full (23 + 1) factorial experiments on a cell with anode area of 5 cm2 and excess oxidant O2 at 200 kPa(abs). For operation in the flow-by mode with 2 M methanol at 2 cm3 min−1 and 353 K the peak power density was 2380 W m−2 with a PtRuMo anode catalyst, while a PtRu catalyst yielded 2240 W m−2 under the same conditions.