Rob Gray

Electrolyte matrix materials for structural battery composites

Structural batteries are a class of battery materials that operate in a similar fashion to lithium-ion batteries on a chemistry level, but have the additional functionality of being able to carry large mechanical loads. This allows them to be used as load-bearing components in electrified transport applications, where their bifunctionality in this role allows for considerable mass savings on a systems level. Most structural battery architectures use carbon fibres as the electrode materials which are embedded in a polymer electrolyte matrix. One of the main factors preventing commercialisation of structural batteries is the lack of a suitable material for the polymer electrolyte matrix.

The aim of Rob's project is to improve the performance and safety of polymer electrolyte matrix materials for structural batteries. This aim will be achieved initially by developing a fundamental understanding of the interface between the polymer electrolyte matrix and the carbon fibre electrodes. Understanding the nature of this interface will be key to optimising both the mechanical and electrochemical properties of the composite, but so far this is an area that has been relatively unexplored in the context of structural batteries. This aim will also be achieved by developing new materials for the polymer electrolyte matrix. Current polymer electrolyte matrix materials rely on flammable organic liquids for ion conduction, and this project will look at utilising safer materials for the polymer electrolyte matrix.

Improving the energy density of electrochemical energy storage devices is critical to accelerating the uptake of electrified transport and a subsequent transition away from fossil-based fuels. Structural batteries offer an enticing pathway to achieving increased energy density, due to the aforementioned benefits of their bifunctionality. Developing a mechanically strong, fast ion conducting, and safe polymer electrolyte matrix material is a key milestone towards the commercialisation of structural batteries. This research is also relevant to the Engineering and Physical Sciences Research Council since it fits in with the energy storage research area.