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Understanding Membrane Degradation Mechanisms Under Heavy Duty Fuel Cell Conditions: A Multi-Disciplinary Approach
In order to develop new durable membrane technologies and devise mitigation strategies to reach desired membrane lifetime, empirical and physical models need to be developed and employed. In this context, understanding the relationship between operation mode and membrane degradation under heavy duty fuel cell conditions is of vital importance. Apart from mechanical degradation such as thinning and pinhole formations, chemical and electrochemical degradation could also take place in perfluorosulfonated acid (PFSA) ionomer membranes. Due to complexity of the underlying processes, degradation mechanisms and their dependence on relevant operating conditions are not generally well established.
We present results from an extensive effort that integrates multi-scale, multi-disciplinary modeling with large–scale accelerated degradation testing data. Results are analysed in view of the relative importance of various membrane degradation mechanisms via various chemical and mechanical processes. The versatile multi-scale modeling framework includes structure formation at molecular/meso-scales, water sorption characteristics, kinetics, as well as continuum modelling of chemical and mechanical degradation processes.
References
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Fig. 1: APC project on heavy duty bus fuel cells (www.apc-hdfc.ca).