Deciphering runaway mechanisms in Lithium-ion batteries by in mortem spectroscopic approaches

Deciphering runaway mechanisms in Lithium-ion batteries by in mortem spectroscopic approaches 
Lithium-ion batteries (LIBs) are increasingly used but it may present a significant risk of thermal runaway in case of mechanical damage, overheating, short circuit, etc. The mechanisms of thermal runaway are macroscopically described in the literature via the analysis of emitted gases and heat, but there is still a lack of information on the chemistries involved onto the material surfaces/interfaces/interphases present at the heart of the battery. These latter are generally characterized before/after cycling (before assembly/after dismantling the battery) while the representative information has to be collected on the materials while the battery is at work/overheating. The analysis of a battery while cycling is clearly not simple because it requires selective techniques at the surface/interface/interphase, sufficiently sensitive and compatible with in situ approach (non-invasive). Recent works (Energy Storage Materials 21 (2019) 347–353; Nature Communications 9 (2018) 661) have shown that it is possible to follow the evolution of the electrode in operation by infrared spectroscopy. 
In the framework of this thesis project, we propose the development of an operando methodology to characterize the cycling and runaway of representative lithium-ion batteries. The information collected will help understand the chemistry at play/ degradation mechanisms present on the materials surface/interface/interphase during thermal runaway in order to reduce the risks to batteries next generation. 
The student will be supervised by a multidisciplinary team and will have access to various analytical and experimental equipment for battery assembly and characterization. The student will have to process, interpret the results, and make regular reports to the project team.

Keywords: Lithium-ion batteries, thermal runaway, operando characterization, IR spectroscopy

• Academic supervisor    Dr. Loïc SORBIER, IFPEN, ORCID : 0000-0001-5591-9848
• Doctoral School    206 - Ecole doctorale Chimie, Procédé, Environnement, U Lyon 1, Claude Bernard
• IFPEN supervisor    Dr. Mickael RIVALLAN, ORCID : 0000-0003-0556-2443
• PhD location    IFPEN, Solaize, France 
• Duration and start date    3 years, starting in the fourth quarter 2025 (Novembre 3)
• Employer    IFPEN
• Academic requirements    University Master’s degree in Chemical Science or Material Science and Engineering
• Language requirements    French and / or English level B2 (CEFR) 
• Other requirements    Skills in electrochemistry is an additional asset

To apply, please send your cover letter and CV to the IFPEN supervisor indicated here below.