Although ionically conducting solids represent the starting point for much of his research, he has extended his interests beyond the confines of this subject alone.

Bruce has published over 390 papers in this area and has been recognized as a Highly Cited Researcher by the Web of Science Group each year since 2015.

Replacing the flammable organic liquid electrolyte currently used in Li ion cells with a solid will enable the use of an alkali metal anode which will increase energy density and improve safety.

Bruce's interests are in understanding the fundamental processes that are taking place and those, such as void and dendrite formation, which ultimately lead to failure of the cell.

[6][7] Until 2023 Bruce led the Faraday Institution's SOLBAT project[8] which aims to "break down the barriers which are preventing the progression to market of solid-state batteries."

The rechargeable lithium-ion battery has revolutionised portable electronics, it will be key to electrifying transport and to delivering secure and stable renewable electricity.