Lithium-ion batteries are poised to play an essential role in the electrification of UK vehicles towards compliance with the government’s goal of zero emissions by 2030. One of the main challenges towards improving the performance (capacity, rate, and cyclability) of ion batteries is understanding and manipulating the electrolyte-electrode interface. As soon as the electrolyte is put in contact with the electrodes, a passivation layer forms; it is known as the solid electrolyte interface (SEI). The SEI consumes active materials and blocks ion diffusion, resulting in reduced battery performance. The dynamics of SEI formation and behaviour remain largely unknown as they are very difficult to measure in a functioning battery.
Most laboratory-scale characterisation techniques are unable to accurately probe and describe the SEI dynamics as the battery is cycled. Increasingly, large user facilities, like synchrotrons and neutron sources, are illuminating the structure and dynamics of battery materials. Small-angle neutron scattering (SANS) and neutron reflectometry (NR) are excellent complementary techniques capable of tracking the change in composition, size, and shape of interfaces. While SANS and NR are ideal to study the SEI, the main challenge is to design measurement cells that can perform well electrochemically during characterisation, commonly referred to as an in-operando experiment, and allow the collection of meaningful data.
Scientific Aims: The primary aim of the project is to develop in operando cells for SANS and NR experiments initially tailored to the materials developed by the supervisory team and partner collaborators. It is expected that the design of the cells will evolve as more findings about the investigated battery systems are obtained and research needs change. The secondary aim of the project is to provide new knowledge and understanding about the SEI dynamics in at least one Li-based and one Na-based battery system.
Practicalities of the Project: The successful candidate will be mainly based at the University of Sheffield where most of the cell assembly and electrochemical testing will be carried out. There will be occasional mid-term visits (1 week to 1 month) to the ISIS Neutron and Muon Source mainly to work on the cell design and to perform tests in the neutron beam. Some short-term visits (up to 1 week) to the University of Cambridge would also be required to work on the thin film deposition of the materials. The duration and frequency of the research visits will be dependent on research needs, project circumstances, and travel restrictions. It is also highly likely that non-UK based neutron sources will need to be visited to perform the SANS and NR experiments or to support partner collaborators with experiments related to the project. This will likely require writing or supporting the writing of proposals for beamtime.
Please see this link for information on how to apply: https://www.sheffield.ac.uk/cbe/postgraduate/phd/how-apply. Please include the name of your proposed supervisor and the title of the PhD project within your application.
We are looking for a highly motivated individual looking to build a research and development career profile in specialist advanced materials characterisation techniques that offer solutions to worldwide problems. You should have or be close to completing a BSc/Masters in Mechanical Engineering, Materials Science, Chemistry, Physics or a related STEM discipline. Mature students and candidates with equivalent industry experience are welcome to apply. The project will require you to travel mainly within the UK, but also internationally so you must have the flexibility and willingness to do so. The highly collaborative nature of the project would also require you to have good interpersonal skills and a cooperative work ethic. If English is not your first language then you must have an International English Language Testing System (IELTS) average of 6.5 or above with at least 6.0 in each component, or equivalent. Please see this link for further information: https://www.sheffield.ac.uk/postgraduate/phd/apply/english-language.