A direct methanol fuel cell based on a novel low-cost nanoporous proton-conducting membrane

We report here a low-cost and improved direct methanol fuel cell (DMFC), ba sed on a novel nanoporous proton-conducting membrane (NP-PCM). The use of t he NP-PCM in DMFC offers several advantages over the Nafion-based DMFC; low er membrane cost (by more than two orders of magnitude), smaller pores (by a factor of two), and lower methanol crossover (by up to an order of magnit ude), which lead to much higher fuel utilization. The NP-PCM also has highe r conductivity (by up to four times). In addition, the ionic conductivity o f the NP-PCM, unlike Nafion, is not affected by heavy metal impurities, thu s it may permit the use of cheaper catalysts and hardware materials. The ma ximum power density achieved so far, at 80 degreesC and at ambient oxygen p ressure, is 85 mW/cm(2) (obtained at 0.35 A/cm(2)). (C) 2000 The Electroche mical Society. S1099-0062(00)06-074-0. All rights reserved.