PhD Spotlight with Connor: Charging ahead with battery research

Connor working on an experimental setup at the UKs synchrotron, Diamond.

Connor is working as a part of the newly founded InFUSE Prosperity Partnership, linking Imperial research with state-of-the-art techniques to progress the energy transition. Connor’s research focuses on the degradation of Sodium-ion batteries, widely considered to be the next big thing in battery energy storage, particularly for large-scale applications.

What inspired you to study for a PhD?

Before university, I didn’t even know that ‘Materials Engineering’ was a thing. As anyone interested in the sciences at school does, I thought my options were limited to medicine, the natural sciences or the more classical engineering routes (civil, mechanical, electrical, etc.). It was only a couple of weeks before the UCAS deadline that I discovered – thanks to my sixth form tutor (thanks again, Mr Hunt!) – the wonders of Materials Engineering.

I applied for and got accepted onto the course at the University of Birmingham and have never looked back. The top-down approach, where you start with an application, assess the materials requirements, and then go to work on manipulating materials at the most fundamental level to achieve these, was something that really resonated with me. In my third year I chose a battery-related group project, thinking they were a worthy application to focus on with this top-down approach. In my Masters’ year, I again chose batteries for my individual project, this time focusing more on recycling. Continuing onto a PhD was the logical next step and one that I didn’t, even for a second, consider not doing. I love the research culture, and where better to go than Imperial!

Sodium-ion Batteries that Connor created and tested.

Can you tell us more about your research?

Currently, my focus is on the cathode materials for sodium-ion batteries (NIBs). Much like the lithium-ion batteries (LIBs) that we all have in our mobile phones, NIBs work by shuttling and storing positively charged ions and atoms, respectively, between two electrodes. The only difference is that sodium batteries shuttle sodium, which is both cheaper and more sustainable than lithium but also heavier and less energy-dense. So, as with everything, the technology has pros and cons.

These similarities and subtle differences make NIBs, in particular, very suitable for large-scale energy storage solutions. Decreasing our carbon footprint and focusing on renewable energy conversion (e.g., wind or solar) requires such storage solutions to operate effectively. They allow us to boil the kettle when the sun isn’t shining and the wind isn’t blowing. Currently, this type of grid-scale storage is dominated by pumped hydro, but cost and geographical constraints limit its global application. NIBs – in my opinion – will be the bridge we need to get us to a truly decarbonised society.

The InFUSE group.

In slightly more detail, my work focuses on trying to understand why some of our most promising NIB materials degrade as fast as they do. I create, or rather I engineer, ways to study these materials as they charge and discharge, helping to paint a picture of what happens to them at the smallest scales in real-time. These specific techniques are labelled ‘operando’. I conduct these experiments at the UK’s national synchrotron facility, firing high-energy X-rays into my batteries to yield all sorts of useful (and awesome) information.

One particular technique to called Xray Absorption Spectroscopy (XAS). It’s very useful for studying batteries as the information you get out relates directly to the chemical and electronic structure of the host electrode material. Looking for unusual changes in the XAS signal as my target electrode charges/discharges is a large part of what I do as a researcher.

What does a typical day involve?

A typical day would see me in the lab making and testing batteries. Production is a complicated and multi-step process, so depending on which stage I’m at, this could mean using furnaces, slurry mixers, coating machines or the testing/cycling rig. Most days will also involve some sort of data analysis too; either cycling data from the lab or some more hardcore stuff from a recent synchrotron experiment. However, as with all research, no day is ever the same and things are always changing!

Can you tell us more about your research group?

I work in two different groups, not uncommon here at Imperial. My primary supervisor is Prof. Mary Ryan in Materials, but most of my lab work is with Prof. Magda Titirici’s Battery team in Chemical Engineering. In my second year, I organised Mary’s biweekly group meetings and also went to both France and China with Magda’s group for conferences.

What do you enjoy outside of your PhD?

I wouldn’t be where I am today if it weren’t for sport. I’ve played field hockey my whole life, and throughout the PhD is no exception. I also love music and regularly attend a ‘pub choir’ in south London with a bunch of friends. Coming from a farm in rural Leicestershire, I also need my regular dose of fresh air and greenery, so often take hikes out of London with my girlfriend.

Slightly closer to home, I really enjoy my work as an Outreach Ambassador for the Department of Materials. As I said at the start, not many people know about Materials as a field, let alone a degree or career option, and that’s a real shame! I’ve done lab demos at Imperial’s Open Days, helped run stands at public events such as The Great Exhibition Road Festival and even organised my own event for 2023’s Pint of Science Festival.

The group of Professor Mary Ryan on an outing to Dishoom.