Oxford University is one of the founder members of the Faraday Institution (https://faraday.ac.uk), the UK’s flagship programme for battery science and technology. Rechargeable lithium-ion batteries have revolutionized the portable electronics industry because of their high energy density and efficiency, and are now widely deployed in electric vehicles. However, they suffer from significant safety and reliability issues, many of which are related to the use of flammable liquid electrolytes. There is a world-wide race to design and manufacture all-solid-state devices that could resolve some of these problems.
Storing the highest energy densities in solid state Li batteries will requires the use of metallic Li as the anode, but Li metal is very soft and reactive, and is proving difficult to use in practical devices. One idea being explored to improve the properties of this component is the use of high Li content alloys, and the simple, single phase Li-Mg alloy has been extensively studied. However, using a solid solution does not much improve the mechanical properties, nor does it offer the potential to form microstructures with a scaffold of second phases on which lithium can re-plate during charging.
This project will design, make and test novel ternary and quaternary Li alloys in which the microstructure/mechanical properties and electrochemical performance can be tuned independently. Novel alloy systems will be explored by selecting promising microstructures with thermodynamic modelling tools, and then these alloys will be manufactured in house, characterised using XRD and electron microscopy techniques to establish the optimised compositions and processing conditions, and then the mechanical and electrochemical performance of the most promising structures will be assessed in prototype battery devices. The SOLBAT project has a large number of industrial partners, with whom a successful new anode material can be exploited.