Thèse soutenue

FR
Auteur / Autrice : Huikyong Kim
Direction : Stéphane Laruelle
Type : Thèse de doctorat
Discipline(s) : Sciences des matériaux
Date : Soutenance en 2014
Etablissement(s) : Amiens
Ecole(s) doctorale(s) : École doctorale Sciences, technologie et santé (Amiens)
Partenaire(s) de recherche : Laboratoire : Laboratoire de réactivité et chimie des solides (Amiens)
Jury : Président / Présidente : Fannie Alloin
Examinateurs / Examinatrices : Stéphane Laruelle, Michel Armand, Lucas Sannier, Charles Delacourt
Rapporteurs / Rapporteuses : Fannie Alloin, Michel Armand

Mots clés

FR

Résumé

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EN

The interphase between the negative electrode and the electrolyte in Li-ion batteries, called SEI, is essentiel for the good cycle-life performance. Numerous studies are dedicated on a better knowledge of its composition, in the hope that it would give information on its properties, but the relationship between the two is still unclear. This is why the formation step of batteries, an industrial process that is meant to form a SEI of high quality, is optimized empirically. This study starts with the development of an analytical method that allows clear evaluation of the passivation property of the SEI layer. The probe molecule that was selected and essentially detectable through GC/MS enables to follow the passivation property/stability evolution during the first charge/discharge. This method is then applied to different parameters that can be found in the formation process, such as the electrolyte composition - influence of linear carbonates and SEI-reinforcing additives -, temperature, Carbon black content in the electrode and calendaring at a pre-charged state. This evaluation is conducted from lab-scale to industrial-scale cells, and it is completed with other characterization tools such as FTIR, microscopy and impedance spectroscopy.