Development of a characterization protocol for the thermal runaway phenomenon of Li-ion batteries

The Li-ion battery is the technology currently used by car manufacturers to provide the energy storage required for electrified vehicles. However, these Li-ion batteries can be the source of incidents with potentially dramatic consequences that can have various origins but are grouped under the term thermal runaway. Thus, understanding and controlling thermal runaway is a major issue from a safety and economic point of view for the car industry. The development of reliable and efficient control and safety systems requires elements of understanding and experimental data that are not present in the literature today.
The PhD student’s objective will be to develop a protocol for the characterization of thermal runaway, by coupling techniques commonly used in the literature (gas analysis, calorimetry etc.) with optical diagnostics to be developed or adapted for this purpose. This original approach will allow the characterization of gas ejections during a thermal runaway as well as the detection of the species formed. This information, which until now has not been available in the literature, will be key to understanding the mechanisms of initiation of a thermal runaway and to identify/predict the risk of combustion.
The thesis will be carried out in collaboration between IFPEN expert in the field of Li-ion batteries and optical diagnostics, and the ICARE laboratory (Orléans, France) expert in the field of combustion and reactivity.
Based on this expertise, the thesis aims to develop a differentiating competence for the understanding and characterization of the thermal runaway of batteries and to establish the link between the phenomena observed at macroscopic level and the physical and chemical mechanisms involved. 

Keywords: Li-ion Batteries, Thermal Runaway, Optical Diagnostics, Electrified vehicles, Combustion

• Academic supervisor    PhD, HdR, DE PERSIS Stéphanie, ICARE 
• Doctoral School    ED 552-Énergie-Matériaux-Sciences de la Terre et de l'Univers (EMSTU)
• IFPEN supervisor    PhD, BARDI Michele, michele.bardi@ifpen.fr, Mobility and Systems division
• PhD location    IFP Energies nouvelles, Rueil-Malmaison, France 75% / ICARE, Orléans France 25% 
• Duration and start date    3 years, starting in fourth quarter 2022
• Employer    IFP Energies nouvelles, Rueil-Malmaison, France
• Academic requirements    University master’s degree Mechanical / Chemical / Materials Engineering
• Language requirements    Fluency in English, willingness to learn French