"AFM coupling and Raman spectroscopy to electrochemical techniques for the advanced diagnosis of Li-ion batteries"
Project ID: ANR-15-CE05-0002
Project leader : Ivan T. LUCAS (MCF)
Collaborators : Blanca TORRES BAUTISTA (Post-doc), Ozlem SEL (CR), Hubert PERROT (DR), Laure FILLAUD (MCF)
The project consists of combining Raman vibrational spectroscopy, gravimetric techniques (microbalance and gravimetric impedance), local microscopy (SPM) and advanced electrochemical methods to perform a complete diagnosis of electrode materials used in lithium batteries. By selecting suitable couplings, the composition and topography mapping of battery materials can be implemented in situ at the micrometer scale (Raman and co-located local microscopy) or ex situ at the nanometer scale (ex situ Raman spectroscopy under SPM tip: TERS or nanoRaman). Monitoring of lithium diffusion within the material or at the interface with the electrolyte will also be possible from the macroscopic scale (EIS and microbalance) to the micro/nano scale (EIS and local microscopy). By tracking and correlating the properties of the active material and the solid electrolyte interphase (SEI) at different scales up to 10 nm, we anticipate major advances in understanding lithium storage capacity losses. The following problems, explaining this decrease in capacity for some promising materials (tin, silicon, LiNi0.5Mn1.5O4, LiCoPO4) will indeed be addressed:
- Instability of the electrode material (chemical, mechanical): loss of active material
- Secondary reactions (non-effective passivation of electrodes): irreversible loss of cyclable lithium and increase of the interfacial resistance
- Limitation of lithium diffusion and retention: limited charging rate and capacity
- SEI composition dynamics by Raman spectroscopy enhanced by core/shell nanoparticles (SHINERS)
- SEI formation dynamics and transport properties using gravimetry techniques (EQCM quartz microbalance, gravimetric impedance) and local probe microscopy.