The use of optical techniques for operando characterization of solid state batteries currently relies on model systems whose designs only partially reflect the behavior of real systems. The candidate will develop innovative optical test cell for unprecedented operando analysis of cross sections of real battery stacks under realistic physical (pressure & temperature) and electrochemical cycling conditions by optical microscopy and Raman spectroscopy.

Monitoring and understanding the complex interactions occurring at the interphases between different components and materials in solid-state batteries is key to improve their performance and lifetime. Optical microscopy and spectroscopy techniques are widely used for post-mortem battery analysis but are more difficult to implement in operando analysis due to the required direct optical access to the region of interest. To circumvent this issue and gain simultaneous access to numerous interphases we target the characterization of cross-sections of battery stacks obtained by new micromachining techniques developed in the lab. The aim of the postdoc is to design and fabricate optical test cells compatible with the prepared battery cross-sections in order to demonstrate and study their electrochemical cycling under controlled temperature and mechanical pressure. Simultaneous operando analysis by optical microscopy and vibrational Raman spectroscopy will be pivotal in studying all-solid battery systems [1]. Prototype cells already available in the lab may be used and incrementally modified to gather preliminary data on limitations, artefacts and reproducibility. The newly developed test cell incorporating temperature and pressure regulation [2] will be used to study degradation mechanisms and characterize all-solid systems during ageing. It carries a good potential for valorization through both patents and publications.

[1] Adv. Energy Sustainability Res. 2, 2100004 (2021) https://doi.org/10.1002/aesr.202100004

[2] Adv. Energy Mater. 13, 1 (2023) https://doi.org/10.1002/aenm.202301338

Location and duration: The position is funded for 18 months and is based in CEA Grenoble campus. The lab is located near the city center of Grenoble, which offers an exceptional working environment as well as a good quality of life, in the heart of the French Alps.

We are looking for a candidate with a background in mechanics and physical instrumentation. Prior hands-on experience on similar advanced custom instrumentation during PhD is desired.

Knowledge in materials characterization & micromachining and/or electrochemistry is a plus.