Investigating interfacial chemistry and materials for emerging anode-free and anode-less sodium metal batteries"

"Anode-free" or "anode-less" Na batteries (ANBs) hold significant promise as a large-scale energy storage technology due to the cost-effectiveness and sustainability derived from the use of earth-abundant Na, as well as the major improvement in battery energy density enabled by the reduction of anode weight. Challenges to develop ANBs include Na dendrite growth on the anode current collector and unfavourable parasitic reactions during Na plating. This requires fundamental study of interfacial chemistry and materials science. This project will investigate the Na/electrolyte/current collector interfaces in ANBs and aim to achieve high reversible capacity and long-term cycling stability. The approaches of the project will include: (i) modifying the surface of Na anode and anode current collector with materials that can redirect the growth of Na dendrites; (ii) characterising the chemical nature and micro-scale morphology of the interface between Na and electrolyte, which will guide the discovery of materials that can act as artificial solid-electrolyte interphase; (iii) the synergy of the previous two approaches to inhibit parasitic reactions and realise highly reversible electrochemical Na deposition.
This project will provide invaluable knowledge of the dynamic interphases between Na anode and the electrolyte, and demonstration of feasibility of ANBs as a promising next-generation energy technology, contributing to the decarbonisation of our society. This project is within the EPRSC research areas of energy storage, electrochemical sciences, and materials engineering, and therefore, it will have the great added value of transforming the chemical understanding and materials innovation to other funded projects that share mutual focuses, such as Na-ion batteries and Li(K)-S batteries.