A high-efficiency, compact design of open-cathode type PEMFCs with a hydrogen generation system

•A 300 W design, 15 cells stack of open-cathode type PEMFC maximum power 355 W at 45 A.•NaBH4 hydrogen generator, the conversion efficiency of hydrogen was about 87%.•HG from NaBH4 in a quick start-up but also eliminates the need for humidification.•The performance of the YZFC-OA stack measuring its power output and dynamics.

In this paper we report on the development of a sub-kW fuel cell stack integrated with a NaBH4-based hydrogen generator. The fuel cell stack was built with 15 open-cathode PEMFCs and employed two fans to supply air for electrochemical reactions as well as for cooling. The open-cathode design simplifies the system’s balance-of-plant. The performance of the present YZFC-OA stack showed an optimum for air fan voltage at 9.0 V. A maximum power 355 W was recorded with H2 inlet temperature 40 °C and stack voltage at 8 V. Reactant solution containing 20 wt.% NaBH4 and 3 wt.% NaOH was introduced into the structured catalyst at constant flow rate. For 14-pcs Ru catalyst and H2 rate of 6.08 L min−1 (0.43 L(H2) min−1 g−1 catalyst), the conversion efficiency of hydrogen was about 87%. The performance and stability of the present YZFC-OA stack, and the feasibility of integrated stack and hydrogen generator have been demonstrated in this study.