Aller au menu Aller au contenu
News
News
News

> About LEPMI > News

Lithium metal negative electrode: metallurgical and electrochemical aspects

Published on June 24, 2021
A+Augmenter la taille du texteA-Réduire la taille du texteImprimer le documentEnvoyer cette page par mail cet article Facebook Twitter Linked In
PhD Defense April 28, 2021
Defense 28 Avril 2021 at 14h00  

 

Lucile Magnier thesis " Lithium metal negative electrode: metallurgical and electrochemical aspects "

thèse lucile

thèse lucile

Abstract
For electric vehicle applications, the use of lithium (Li) metal as negative electrode is very promising because Li has the highest theoretical capacity and a low electrochemical potential. Unfortunately, stripping and plating heterogeneities lead to dendrite growth on Li electrode surface which induces short-circuits. The use of a solid polymer electrolyte is one of the possible solutions to mitigate dendrite growth. However, batteries still have a limited cycle life whose failure is related to Li metal negative electrode.
The challenge of this PhD was to understand the mechanisms at stake in the Li metal electrode causing battery end-of-life. Particular attention was paid to correlate Li metallurgy and its impact on battery failure. Using X-ray computed tomography, the samples were analyzed in a non-intrusive manner while avoiding contact with air and moisture.
A first study focused on the characterization of Li metal microstructure (precipitates, Li grain size and inclusions). Thanks to the insights provided by this study, the evolution of Li metal morphology during cycling could be followed in two types of assemblies (Li symmetric cells and batteries) and correlated with Li microstructure. The Li symmetric cells allow, thanks to a polarization of a few days or weeks, to characterize the impact of Li oxidation and reduction on Li electrode morphology. The study of batteries, requiring several months of cycling, allows to observe the degradation of the Li metal electrode upon cycling and to deepen the mechanisms of battery failure.
 
Directeur de thèse : Eric MAIRE (Directeur de Recherche), Renaud BOUCHET (Professeur) et Didier DEVAUX (Chargé de Recherche)

Composition du jury :
Arnaud DEMORTIÈRE Chargé de Recherche, UPJV
Michel ROSSO Directeur de Recherche, Ecole Polytechnique
Marie-Liesse DOUBLET Directeur de Recherche, Université Montpellier
A+Augmenter la taille du texteA-Réduire la taille du texteImprimer le documentEnvoyer cette page par mail cet article Facebook Twitter Linked In

Date of update June 24, 2021

Université Grenoble Alpes