Stephen O’Sullivan

Stephen’s research is focused on developing cost-effective and environmentally friendly sodium ion batteries (NIBs). The primary application for this technology is in battery energy stationary storage (BESS), to aid curtailment issues commonly associated with solar and wind energy. Sodium is promising as an alternative to lithium for such applications due to being far cheaper and more abundant.
During his PhD, he aims to develop and demonstrate a high-capacity sodium ion battery, including anode, cathode, and electrolyte. In developing these components, materials will be selected to play into the inherent strengths of NIBs by choosing abundant and cheap solutions. Materials are also selected to keep in theme with the environmentally friendly side of the project as the end goal is to produce technology that will eventually contribute to renewable energy infrastructure. An important part of the design of both the anode and cathode materials in his work is the application of nanotechnology that has previously been developed by the group and applying it to NIBs in a novel way to give the batteries the best opportunity to out-perform current NIB technology and rival commercial LIBs. Instead of low specific capacity hard carbon anodes typically associated with NIB anodes, alloying materials will be used in conjunction with nanomaterials. This will allow the battery to benefit from the high capacity offered by alloying metals, while bespoke nanoarchitectures will help mitigate pulverisation which has thus far hindered the application of these materials. Similarly, nano structuring will be used in the cathode to help improve the poor conductivity and sluggish performance associated with materials such as sodium iron sulphate.