An alternative concept for DMFC – Combined electrolyzer and H 2 PEMFC

The article introduces a novel concept that combines a methanol electrolyzer and a H2-PEMFC to a power source for small scale applications, e.g. portable electronics. Due to the low energy requirements of methanol electrolysis the released hydrogen contains enough energy both to maintain the electrolysis and to provide power to the application device. The concept is comparable to DMFC technology, but offers additional features, which make it interesting when developing the methanol based small scaled power sources further. The article considers those features both theoretically and experimentally by a proof-of - the concept approach. Comparison to DMFC is made through a semi-empirical modeling which determines the conditions where the combined system has a better power efficiency. In addition, some interesting properties like tolerance to high methanol concentrations are considered and justified. Finally, a rough comparison of the stack sizes needed by the two concepts is made through an illustrative design example.