Development of a 30 W class direct formic acid fuel cell stack with high stability and durability

A medium-scale DFAFC stack was designed and fabricated in this work. The power output of this stack was high to 32 W, which can satisfy the power requirement of most portable electrical devices. The ultrasonically mixed Pt/C + Pd/C catalyst was optimized as the anode catalyst for the stack fabrication by using a single cell. The feeding formic acid concentration and oxygen flow rate respectively in anode and cathode side were also experimentally optimized before the stack fabrication. Under the optimal operation conditions, the life time test was carried out for the DFAFC stack using the optimal anode catalyst. The stack can stably operate for about 50 h with 1.5 L fuel supplied, and its high durability was confirmed by the 240 h continuous life time test.