Optimal Sustainable Fuel Cell Stack with Cellulosic Alkaline Membranes

Hydrogen was generated in situ in a reactor with aluminum scrap and water together with NaOH as catalyst. CO2-free air was obtained by filtering atmospheric air with a KOH solution. A fuel cell stack prototype with four cells, H-2-generator, and a CO2 cleaning device demonstrated the concept. Direct voltage and power evaluated the stack operation. The results showed that the stack with generated H-2 had a performance 18% smaller than with pure H-2, that is, 3.77 V (I = 0 A), and 2.70 W were obtained. Experimental data were used to validate a sustainable (sustainable alkaline membrane fuel cell) stack transient mathematical model. A sensitivity analysis showed the effect of membrane KOH content (y = 20% w/w, y = 40% w/w, and y = 50% w/w) on performance and found that y(opt) = 40% w/w leads to a stack net power maximum, which was utilized to produce experimental data. The peak was steep, due to a net power drop of similar to 42% with y = 50% w/w, and similar to 50% with y = 20% w/w in comparison to y = 40% w/w. In sum, H-2 production embedded in the stack demonstrated that there is potential for system practical implementation.