Faites connaître cette offre !
Reference : UMR7314-JEACHO-001
Workplace : AMIENS
Date of publication : Wednesday, September 09, 2020
Scientific Responsible name : Raphaël JANOT
Type of Contract : PhD Student contract / Thesis offer
Contract Period : 36 months
Start date of the thesis : 2 November 2020
Proportion of work : Full time
Remuneration : 2 135,00 € gross monthly
Description of the thesis topic
Li-ion battery technology is one of the most efficient ways to store energy with high energy density. Li-ion batteries are now used all over the world for portable electronics and play a key role in the development of electric vehicles. Nevertheless, the low lithium abundance and its uneven distribution on Earth may lead in the next decades to severe resources shortage. Na-ion batteries are catching a lot of attention as a possible alternative due to the unlimited sodium abundance. Na-ion battery performances have been strongly enhanced in the last few years, but safety issue due to the use of a flammable liquid electrolyte is a major drawback. This is why Na-based All-Solid-State Batteries (Na-ASSB) could be a promising “next generation” of electrochemical energy storage devices.
To achieve such a challenge, fast solid-state electrolytes need to be developed. Scientific activities are mainly focussed on Li+ ionic conductors such as Li7La3Zr2O12 and Li10GeP2S12 for the Li-based All-Solid-State Batteries (Li-ASSB) but, more recently, several well known phases such as Na3PS4, NASICON phases or β-alumina regain a lot of interest for their possible applications in Na-ASSB. All those phases present decent ionic conductivities, which can reach 10-3 S.cm-1 at room temperature for some of them. However, they are often suffering of a narrow electrochemical stability window, or difficulties to form stable interfaces with the electrode materials.
Recently, a new class of solid-state electrolytes has been proposed for Li-ASSB: the Li-Rich Anti-Perovskites related to the archetype Li3OCl.1,2 Their intrinsic high ionic conductivity, stability against lithium metal3 coupled to a low temperature synthesis process make them materials of great interest. In this project, we propose the synthesis, structural and ionic conductivity characterizations of new Li and Na Anti-Perovskite materials as solid electrolytes. One of the great interests of Li or Na-antiperovskites is their chemical tunability. Anti-Perovskite phases of general formula X3+B2-A- can be easily modified by chemical substitution. Those chemical substitutions are expected to increase their ionic conductivity at room temperature.
Different synthesis routes will be explored during the PhD thesis such as solid state synthesis (followed by a subsequent quenching in some cases), mechano-chemistry, Spark Plasma Sintering (SPS). The materials will be characterized by X-Ray diffraction, Infrared and Raman spectroscopies, SEM and TEM, Thermal Analysis (DSC-TGA), ionic conductivity by Electrochemical Impedance Spectroscopy (EIS), electrochemical stability by Cyclic Voltammetry and Galvanostatic cycling, etc…
1. Zhao, Y. & Daemen, L. L., J. Am. Chem. Soc. 134, 15042–15047 (2012).
2. Schwering, G., Hönnerscheid, A., van Wüllen, L. & Jansen, M., ChemPhysChem 4, 343–348 (2003).
3. Emly, A., Kioupakis, E. & Van der Ven, A., Chem. Mater. 25, 4663–4670 (2013).
This PhD thesis is a collaboration between the Laboratoire de Réactivité et Chimie des Solides (LRCS) in Amiens and the UMICORE company.
Based in Amiens at the University of Picardie Jules Verne, the LRCS laboratory is a world famous research lab for its activities on lithium-ion batteries, next generation batteries, hydrogen storage and photovoltaics. LRCS is also a key member of the collaborative French network RS2E on energy electrochemical storage (www.energy-rs2e.com), which aims at improving current generations of batteries and at developing new systems for energy storage.
Umicore is a Belgian company, specialized in the refining and recycling of precious metals and the manufacture of specialized products from different metals. Umicore is dedicating most of its R&D efforts to clean mobility materials and recycling.
We talk about it on Twitter!