• Aaron Villoslada Rodriguez

  • Theme:Chemical Energy Converters
  • Project:Lifetime modelling of PEM fuel cell stacks
  • Supervisor: Tom Fletcher
  • The Gorgon's Head - Bath University Logo
Photo pf Aaron Villoslada Rodriguez


From a young age, family members asked me what I wanted to do when I became older. As a naive kid, I was and still am. My responses always orbited around scientific disciplines. I used to see myself in a white lab coat looking through a lens of knowledge and expertise that will assemble so much good for the world. Years passed, and the reality of becoming the new Dexter was reduced. It reached a certain point when I realized the lonely, phrenic and obsessed old man in a white lab coat was no longer at the cutting edge of research. Individuality is a quality of the past, while teamwork and group development is and will be how advances are obtained. These reasons are why I have made certain decisions in my academic history, such as studying physics with renewable energy at the University of Dundee, where the broadness of the physical world was shown to me during my time there. This helped me to understand a whole new and complex system. As I mentioned before, the collaboration of multiple points of view produces and enhances the quality of any piece of work. If we increase this by mixing numerous angles of view and different backgrounds when solving a problem, not only one rounded solution may come up, but various and diverse solutions will arise for the same issue. This is what AAPS CDT is for me and why I have decided to invest my next 4 years with them.

Considering my physics background, I am interested in how energy is obtained and which methods are used for its production. By making these systems more efficient and reliable, we increase overall optimization by reducing the usage of resources. More circular energy production could be obtained by transferring these into all scenarios.


  • I can whistle in reverse.
  • I still use my fingers to count when the addition exceeds 20.
  • My ideal superpower is time control, even after watching all the science-fiction movies.
  • I can hold my breath for up to 2 minutes ( when I am fit ).
Lifetime modelling of PEM fuel cell stacks

The development of a hydrogen economy is a key part of the UK’s commitment to net zero as recommended by the Climate Change Committee. Whereas battery electric vehicles are expected to satisfy the vast majority of light duty vehicle applications, their limited energy density means that they are unsuitable for many energy-dense applications such as long-distance haulage, shipping, rail and aviation. Equally, long charging times significantly affect their suitability for high availability applications.

Fuel cells overcome these issues by separating the energy storage from the energy conversion, enabling refuelling times similar to those of conventionally fuelled vehicles (<5 minutes) while maintaining zero emissions at the point of use. However, durability is key challenge for fuel cells in these markets where the system lifetime target is 25,000 hours (by 2030) and 1 million miles for Class 8 truck applications according to the US DoE.

Aaron's research aims to tackle this challenge by producing predictive models of the causes of PEM fuel cell degradation, seeking to understand not just individual degradation modes, but the interactions between them and their development over the lifetime of the stack. Current techniques are usually split into theoretical and empirical models. Whereas theoretical models are predictive; for electro-chemical devices they tend to be highly complex, slow to simulate and contain many parameters which are difficult to determine. Conversely, empirical models are fast running, but tend to be highly simplistic have low generality. The aim of this project will be to bridge this gap to enable investigation into how design and control strategy changes will affect the long-term fuel cell durability.

In addition to the main project aim, several secondary objectives are proposed. These will form a series of interim milestones for the project and include development of standardised test procedures, accelerated aging methods, condition monitoring techniques, requirement specification for future cell development and recommendations for control strategy targets. 

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