Accession Number:

ADA622747

Title:

Mechanical Characterization of Anion Exchange Membranes Under Controlled Environmental Conditions

Descriptive Note:

Doctoral thesis

Corporate Author:

COLORADO SCHOOL OF MINES GOLDEN

Personal Author(s):

Report Date:

2015-05-11

Pagination or Media Count:

125.0

Abstract:

While proton exchange membrane PEM fuel cells have been the focus of development in the past, anion exchange membranes AEM have the potential to dramatically lower the cost of fuel cells by utilizing non-noble catalysts and a variety of fuel sources. Although chemical degradation typically dominates membrane failure pathways in a fuel cell, mechanical breakdown due to humidity cycling is a common occurrence. This thesis aims to understand the mechanical properties of anion exchange membranes under fuel cell operating conditions. A humidity delivery system was developed for the TA Instruments ARES-G2 rheometer to allow for testing at a range of temperatures 30-100 C and relative humidity conditions 0-95 RH. A modified Sentmanat Extensional Rheometer SER was used to perform tensile-like testing using less than 5 of material needed for a traditional tensile tester. These tools established metrics for a robust membrane through mechanical characterization across temperatures and humidities. A pentablock AEM with a balance of stiff and elastic blocks was shown to have adequate conductivity up to 60 mScm at 90 C and 95RH, low water uptake 25, and good mechanical integrity under dry and hydrated conditions, showing potential for being durable under hydration and mechanical stresses.

Subject Categories:

  • Physical Chemistry
  • Electrochemical Energy Storage

Distribution Statement:

APPROVED FOR PUBLIC RELEASE