Abstract

As molecular weight analysis of polymer electrolyte membrane for fuel cells has an advantage in sensitivity of membrane damage detection, it can detect slight changes in membrane damage even in a short-term durability test. Modelizing the relationship between the molecular weight of polymer and the probability that the polymer will react with a radical allows calculation of molecular weight reduction as an approximation to a curve. Hydrogen peroxide exposure testing was carried out on a membrane to experimentally confirm that the decrease in molecular weight due to degradation of the membrane follows the molecular weight reduction curve. It was also experimentally confirmed by a real fuel cell durability test that the reduction in molecular weight of membrane under the fuel cell operating conditions follows the molecular weight reduction curve. With the molecular weight reduction curve, it becomes possible to predict the degree of degradation in long term durability tests from degradation in short term tests, thereby shortening the test time necessary for evaluating the durability of the polymer electrolyte membrane to around one fifth or less.

References

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Author (organization or company)

• Atsushi HIRAIDE（Automobile R&D Center）
• Akira NAKAHARA（Automobile R&D Center）

Publication Information

Article of Honda R&D Technical Review Vol.30 No.2 (103 - 109)

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Citation Information