The development of a sodium borohydride hydrogen generation system for proton exchange membrane fuel cell

This paper develops an on-demand hydrogen generation system, which can produce hydrogen from sodium borohydride (NaBH4) solution, to operate proton exchange membrane fuel cell (PEMFC). We first build the hydrogen generation system, which hydrolyzes NaBH4 in a batch reactor to provide a continuous supply of hydrogen to drive the PEMFC. We also discuss the impacts of solution concentration and batch volume. In addition, we develop a simulation model that evaluates the hydrogen generation and temperature responses of the system. Furthermore, we design a control strategy to adjust the batch intervals of NaBH4 solution according to the PEMFC loads. We then implement the designed control on a microcontroller and integrate it with a PEMFC for experimental verification. The results confirm that the developed on-demand hydrogen generation system can hydrolyze NaBH4 with a conversion rate of more than 90% so that it to continuously supplies hydrogen to drive a 3 kW PEMFC.