Operando Auger/XPS using an electron beam to reveal the dynamics/morphology of Li plating and interphase formation in solid-state batteries

Fri, 07 Apr 2023 00:00:00 +0000

Cross-section nano-Auger/SEM analysis to reveal bulk chemical/morphological properties of composites for energy storage

Tue, 07 Mar 2023 00:00:00 +0000

Composite Mn–Co electrode materials for supercapacitors: why the precursor's morphology matters!

Fri, 07 Oct 2022 00:00:00 +0000

Surface Reactivity and Surface Characterization of the Layered β(III)-CoOOH Material: an Experimental and Computational Study

Thu, 15 Apr 2021 00:00:00 +0000

Cross-Section Auger Analysis to Study the Bulk Organization/Structure of Mn-Co Nano-Composites for Hybrid Supercapacitors

Thu, 07 Jan 2021 00:00:00 +0000

Cross-section Auger imaging: A suitable tool to study aging mechanism of conversion type electrodes

Thu, 17 Oct 2019 00:00:00 +0000

Cross-Section Auger/XPS Imaging of Conversion Type Electrodes: How Their Morphological Evolution Controls the Performance in Li-Ion Batteries

Sat, 22 Jun 2019 00:00:00 +0000

Cross-section ✂️ 2017...

Sun, 01 Jan 2017 00:00:00 +0000

🔍 Overview

To investigate in depth morphology and chemical distribution of composite materials and electrodes, I developed cross-sectioning methods using Ar+ ions beam coupled to Auger analysis. It allows analyzing morphological and chemical informations of a micro-scale region of interest with a nano-scale resolution (~30 nm lateral, ~3 nm depth). This approach was applied to:

Composite electrodes based on conversion materials for batteries: conversion materials such as MSnSb (M=Ti or Nb) overcome huge volume expansion (>200%) and very fast amorphization so that conventional XRD/SAXS as well as TEM (focusing individual particles) are unsuitable tecnhiques to study their reversibility. This was performed in collaboration with L. Monconduit (ICGM).
Nano-composite powders for supercaps: MnO2-CoOOH performance being governed by their assembly, morphology and porosity at both the nano- and micro-scales, standard XRD (coherent domain size), SEM (surface) and TEM (individual particles) are unsuitable tecnhiques to fully asses their properties at once. It started as a preliminary collaboration with D. Giaume (Chimie ParisTech) and L. Guerlou-Demourgues (ICMCB) through the RS2E network. As the result were conclusive, this method was pursued in a larger project funded by the REGION Nouvelle-Aquitaine and led by D. Flahaut (IPREM).

🎯 Key Findings

Composite electrodes: The cross-section/Auger approach demonstrated for the first time that conversion of MSnSb (M=Ti or Nb) still occurs after 400 cycles. It occurs through a shell to core expansion/break up of the particles upon cycling. This leads to a micron scale spreading that fills the initially large and highly porous structure of the electrodes together with a large electrode volume expansion.
Composite powders: The cross-section/Auger approach revealed for the first the Mn-Co scale organization together with the morphology and porosity at both the micro-particles and nano scales.

👤 My Contributions

Development of both the electrodes / powders cross-sectioning and Auger analysis protocols with the support of J.-B. Ledeuil (CNRS Research Engineer, IPREM).
Co-supervision of 🎓 A. Lemoine’s PhD thesis (20%).
Download A. Lemoine PhD thesis - PDF (fr-en)

📢 Communication

📄 6 publications
🎤 2 international conferences

🚀 Next Steps

Cross-section were then applied to solid-state battery stacks in the

Cross-Section |