Correlative X-ray and Neutron Studies of Li-ion Battery Performance and Degradation

The Li-ion battery was one of the transformative technologies of the 20th century and promises to have wider impact in the 21st century with the rapid uptake of electric vehicles. Battery degradation remains one of the most pressing issues facing vehicle electrification and is also critical across a range of industries from consumer electronics to aerospace. The increasingly demanding applications for Li-ion batteries mandate an improved understanding of the performance, degradation and failure of both materials and devices, and moreover motivates the exploration of new chemistries for post Li-ion batteries.

To advance this understanding, researchers have a portfolio of microscopy, spectroscopy, diffraction and analytical tools, and the increasing trends towards multi-modal and in-situ or operando characterisation provides an opportunity probe the highly correlated physio-chemical phenomena associated with battery operation and degradation. For example, neutron techniques provide a high degree of complementarity to X-ray tools with their sensitivity to nuclear and electron density respectively.

In this programme, we will develop combined neutron imaging and diffraction tools, alongside novel X-ray imaging techniques - in concert, these tools provide an understanding of battery operation and degradation from the 'atom to the device' level. Leveraging the world leading capabilities across Diamond, ISIS and UCL, there is a unique opportunity to understand and explain degradation phenomena that arise during battery operation (for example as a function of voltage, temperature or cycle life), which will inform new approaches to materials and device, design and operation.

The production and processing of materials accounts for 15% of UK GDP and generates exports valued at £50bn annually, with UK materials related industries having a turnover of £197bn/year. It is, therefore, clear that the success of the UK economy is linked to the success of high value materials manufacturing, spanning a broad range of industrial sectors. In order to remain competitive and innovate in these sectors it is necessary to understand fundamental properties and critical processes at a range of length scales and dynamically and link these to the materials' performance. It is in this underpinning space that the CDT-ACM fits.

The impact of the CDT will be wide reaching, encompassing all organisations who research, manufacture or use advanced materials in sectors ranging from energy and transport to healthcare and the environment. Industry will benefit from the supply of highly skilled research scientists and engineers with the training necessary to advance materials development in all of these crucial areas. UK and international research facilities (Diamond, ISIS, ILL etc.) will benefit greatly from the supply of trained researchers who have both in-depth knowledge of advanced characterisation techniques and a broad understanding of materials and their properties. UK academia will benefit from a pipeline of researchers trained in state-of the art techniques in world leading research groups, who will be in prime positions to win prestigious fellowships and lectureships. From a broader perspective, society in general will benefit from the range of planned outreach activities, such as the Mary Rose Trust, the Royal Society Summer Exhibition and visits to schools. These activities will both inform the general public and inspire the next generation of scientists.

The cohort based training offered by the CDT-ACM will provide the next generation of research scientists and engineers who will pioneer new research techniques, design new multi-instrument workflows and advance our knowledge in diverse fields. We will produce 70 highly qualified and skilled researchers who will support the development of new technologies, in for instance the field of electric vehicles, an area of direct relevance to the UK industrial impact strategy.
In summary, the CDT will address a skills gap that has arisen through the rapid development of new characterisation techniques; therefore, it will have a positive impact on industry, research facilities and academia and, consequently, wider society by consolidating and strengthening UK leadership in this field.