Prof. Luke O'Dell
In residence at
Dr Michaël Deschamps
Understanding sodium batteries using advanced and operando magnetic resonance methods
Sodium batteries have the potential to replace lithium batteries as a cheaper and greener energy storage technology. However, currently sodium electrochemistry is not as well understood as lithium, and there remain several scientific challenges to overcome. One major issue is that the development of the solid electrolyte interphase (SEI) layer that forms on the electrode surface during cell cycling is not well understood and the nature and properties of these SEI products can dramatically impact the performance of the device (e.g., limiting its capacity or cycle life). In this project we will use advanced magnetic resonance characterisation techniques, including state-of-the-art operando measurements, to better understand SEI formation in sodium batteries. Novel electrolytes based on ionic liquids and incorporating various additives will be used to target the formation of stable SEI products with high Na+ ionic conductivities. This project will combine the expertise of A/Prof O’Dell and Deakin University’s world-leading Electromaterials research team with the state-of-the-art facilities and expertise of Prof Deschamps and the CEMHTI-CNRS nuclear magnetic resonance (NMR) facility, where the operando capability has been established and tested on lithium batteries using the 7Li isotope. We will extend this work to the more challenging 23Na nucleus, and the operando experiments will be complemented by extensive electrochemical testing and ex situ NMR measurements. A/Prof O’Dell and Prof Deschamps already have an established and productive collaborative relationship and will supervise a cotutelle PhD student who will also work on this project, jointly funded by Deakin and CNRS. The project will also be complemented by other ongoing projects at Deakin, including a larger sodium battery research program funded by the Australian Research Council (DP210101172).
Publications in relation with the research project
Two novel solid-state sodium battery electrolyte materials (a polymerised ionic liquid block co-polymer and a zwitterionic plastic crystal) have been characterised by high-field NMR spectroscopy. The results allow the identification of the Na+ solvation environment, which will determine the ion transport mechanism. Additionally, solid-electrolyte interphase products formed in sodium metal batteries containing two different ionic liquid electrolytes have been studied by the same experimental method and a breakdown product of the ionic liquid anion has been tentatively identified. These results demonstrate the power of NMR to provide new insights into sodium battery materials.