Batteries | Interview with the Author—Dr. Ashley Willow

Dr. Ashley Willow’s published paper:

“Design and Validation of Anode-Free Sodium-Ion Pouch Cells Employing Prussian White Cathodes”
by Ashley Willow, Marcin Orzech, Sajad Kiani, Nathan Reynolds, Matthew Houchell, Olutimilehin Omisore, Zari Tehrani and Serena Margadonna
Batteries 2025, 11(3), 97; https://doi.org/10.3390/batteries11030097   
Available online: https://www.mdpi.com/2313-0105/11/3/97

The next battery revolution? Dr. Ashley Willow shares cutting-edge research on Prussian white cathodes for anode-free systems. Below is a short interview with the author.

1. Could you introduce yourself?

My name is Ashley Willow and I hold a B.Sc. chemistry, M.Sc. Ccatalysis, and Ph.D. electrochemistry. I am a Senior Lecturer at Swansea University in the Department of Chemical Engineering and research within the Circular Approaches to Utilize and Retain Energy (CAPTURE) Centre of Expertise. My current research focus is on the understanding of traditional sodium-ion batteries and those that operate in the so-called “anode-free” format. I have a background in pouch cell assembly and have established pouch cell and cylindrical cell production facilities at Swansea University. I focus on understanding the issues associated with the transfer from coin cell to commercial cell formats in these chemistries. Before my most recent position at Swansea University, I spent several years in industry in the fields of post lithium-ion batteries (Lithium Sulfur) and investigating the electrochemistry of steel. I organized the international Sodium ion conference at Swansea University (STRIKE) and led the scale-up research efforts on sodium-ion anode-free cells.

2. Please share what inspired your research?

A few key contributing factors inspired this research in particular. Firstly, working in the industry on pouch cell assembly and energy density calculations gave me key insights into how cell design influences energy density. I wanted to apply this experience to sodium-ion batteries, in particular to the relatively new area of sodium-ion anode-free batteries by realistically demonstrating the potential of this technology. I hope this work can guide the development of sodium ion anode-free and help bridge the industry-academia gap. This thinking led to the development of our open cell calculator (WattCell · Streamlit), a key outcome of the publication. Another inspiration is the rapid growth in understanding and application of sodium-ion batteries, which pushes everyone in our group to be part of this rapidly growing field.

3. In your career in battery research, which mentor or predecessor has had the greatest influence on your scientific thinking?

I have been very lucky to have many great mentors and colleagues in academia and industry who have influenced me in different ways. My Ph.D. supervisor, Prof. Gary Attard, was hugely influential at the start of my career. His enthusiasm for experimental and fundamental electrochemistry sticks with me to this day. In industry, colleagues and mentors at OXIS Energy Ltd. fostered an environment of open scientific debate and discussion, which I continue to uphold. I currently work closely with many colleagues at Swansea University and, in particular, note Prof. Serena Margadonna’s influence. She encourages scientific rigor and ambition in battery research.

4. Why did you choose to publish with Batteries, and how was your experience?

I particularly chose Batteries as the topic was well suited, especially concerning the Special Issue. The experience was very positive. Writing using the provided templates was straightforward, updates were clear and regular, the reviewer comments were helpful, and I am very happy with the final publication.

5. What role did you play in your research team, and how did teamwork affect the paper’s outcome?

Teamwork was an essential pre-requisite of this work, which is true of most battery research due to its multidisciplinary nature. We required high-quality cathode synthesis (Dr. Sajad Kiani), coating and online cell calculator development (Dr. Marcin Orzech), and pouch cell assembly (me), to name a few factors. Without bringing these aspects together the paper would not have been possible.

6. What trends and technologies do you see shaping the future of battery technology?

Sodium-ion batteries will be hugely influential in the next decade. The commercial developments are essentially locked in due to efforts from large battery manufacturers and recent breakthroughs in energy density and cycle life. Sodium ion batteries are very suited for low-cost storage in a number of applications so the proliferation of this technology will expand naturally. I see sodium ion anode-free technology as very promising; the stack pressure requirements are lower than the lithium metal anode-free equivalent and they offer better cycle life also (although the literature in this area is sparse). Due to the removal of hard carbon, anode-free offers energy density advantages compared to intercalation-based sodium-ion batteries. Investigations to further improve the cycle life of anode-free are ongoing and could hugely shape the commercial direction of battery technology.

7. What impact do you hope your research will have, and what key innovation do you see in your paper?

This article gives a clear direction in moving from single-layer pouch cells to multilayer cells with reasonable energy densities using a battery format (anode-free) that has growing research attention. This is the first demonstration of Prussian white-based sodium ion anode-free pouch cells and the start of the innovation process.