This paper reports on a single alkaline exchange membrane direct formate fuel cell (AEM DFFC) consisting of a carbon-supported palladium catalyst at the anode, a quaternized polysulfone membrane, and a non-precious Fe-Co catalyst at the cathode. It is demonstrated that the AEM DFFC yields a peak power density of 130 mW cm(-2) with 5 M potassium formate (HCOOK) at 80 degrees C. It is further shown that with the addition of KOH to the anolyte, the peak power density rises to as high as 250 mW cm(-2) at the same operating temperature. In addition, the AEM DFFC was also tested at 100 mA cm(-2) for more than 130 h and no significant degradation in performance is found. The results reported in this work suggest that formate salt (HCOOM, M+ = Na+ or K+) is a potential fuel for alkaline-type direct liquid fuel cells. (C) 2013 Elsevier Ltd. All rights reserved.