High-power direct ethylene glycol fuel cell (DEGFC) based on nanoporous proton-conducting membrane (NP-PCM)

We recently reported the development of a new nanoporous proton-conducting membrane (NP-PCM) and have applied it in a direct methanol fuel cell (DMFC) and in other direct oxidation fuel cells. The use of the NP-PCM in the DMFC offers several advantages over the Nation-based DMFC including lower membrane cost, lower methanol crossover which leads to a much higher fuel utilization and higher conductivity. In this work, we found that the 90 degreesC swelling of the NT-PCM is only 5-8% and that the diffusion constant of methanol at 80130 degreesC is higher by a factor of 1.5-3 than that of ethylene glycol (EG). The maximum power density of methanol/oxygen and EG/oxygen FCs equipped with a 100 mum thick NP-PCMs is 400 and 300 mW/cm(2) respectively, higher than that for a DMFC based on Nation 115 (260 mW/cm(2) [Eletrochem. Solid-State Lett. 4 (4) (2001) A31]. This puts the DEGFC in direct competition with both DMFC and indirect methanol FC. Ethylene glycol (EG) is well known in the automobile industry and in contrast to methanol, its distribution infrastructure already exists, thus it is a promising candidate for practical electric vehicles. (C) 2002 Elsevier Science B.V. All rights reserved.