TOPIC #13
Mapping heterogeneities in Na-ion cells by multiscale synchrotron techniques
Research area: Post Li-Ion Technologies, Advanced Methods
Keywords: Na-ion battery; operando characterization; synchrotron; structure-property relationship; sodiation heterogeneities; tomography
Supervising team: Sandrine LYONNARD (CEA) & Jakub DRNEC (ESRF)
Abstract
Na-ion batteries (NIBs) have a design principle close to lithium-ion batteries (LIBs), allowing their recent commercialization. NIBs are free of Li and Cu (strategic metals), less costly, can be transported safely at 0 V in principle, and withstand fast charging/discharging rates. However, they feature relatively poorer energy density and cycle life compared to LIBs. Pushing the energy density while maintaining power performance would increase NIB market share, a challenge that requires a detailed understanding of reaction and degradation mechanisms inside cells during cycling. In this project, we propose a multi-modal X-ray based approach to spatially map heterogeneities in Na-ion systems and understand the chemomechanics by a combination of ex situ and in situ synchrotron tomographic methods. We will use scanning/tomographic techniques to 2D/3D scan full commercial-format batteries in operando mode and resolve structural changes with submicron resolution, combined with electrode-scale characterizations including nanoholotomography to analyse the local morphology of both positive/negative electrodes. The investigated systems will be either 18650 cells or pouch cells using different chemistries both in fresh and aged states. In perspective, the developed methodologies will be transferred to a model anode-free solid-state Na-ion battery, to track interfacial reactivity and electrodeposition processes.
Interest for the student
Expected mobility: A 3 months secondment will be performed at the European Synchrotron Radiation Facility (ESRF) in Grenoble to advance the data analysis from cell-scale tomographic studies planned on ID31, BM05 and ID16b beamlines. Modern methods for data processing, reconstruction and segmentation will be developed in tight collaboration with beamline scientists and IT group there. The ESR will present his/her results at national conferences as the GFECI or PEPR battery days for instance, and attend 2-3 international conferences as IBA, ISE, ACS, ECS, ESRF User Meeting. Visits to key partners (as cell producers and chemistry labs) will be regularly organized in France. The ESR will also attend the Destiny program meetings and events.
Career opportunities: The PhD project will provide skills in battery chemistry and analytical characterization, including solid knowledge on advanced synchrotron techniques which are key in the field and growingly used by both academic and industry sectors. Particularly, tomography enables 3D views of real cells as well as dynamic mapping of their morphological properties, enabling to visualize and quantify the interior of a battery at unprecedented spatiotemporal scales. The ESR will gain expertise in designing and performing such cutting-edge experiments, as well as developing complex data analysis pipelines based on python-codes. He/she will be able to manipulate materials, prepare cells, cycle and study them, as well as understand the main challenges in Na-ion technology and beyond, as part of a team working on different types of energy materials. He/she will acquire communication and organizational skills by working in this interdisciplinary environment with regular interactions with chemists, materials scientists, industry partners, synchrotron scientists. He/she will attend group meetings and benefit from interactions with other ESRs in both the hosting lab and the secondment lab. He/she will acquire a broad knowledge in battery research, positioning him/her well in the dynamic landscape of energy storage technologies in Europe, where many gigafactories are currently emerging, including on novel systems as sodium-ion.
Contacts
IMPORTANT: you may contact the potential supervisors to have more information about the topic, however, sending them your application directly is not permitted.
