Description du sujet de thèse

A contemporary and acute scientific, technological and societal challenge linked to addressing the UN SDG N°7 consists in shifting-paradigm from Lithium-ion Batteries (LiBs: electrolyte is a liquid or a gel) to high performance safer and sustainable-by design Solid-State Batteries (SSBs: solid-state batteries). Beyond electrochemical energy storage and electric mobilities key-drivers, developing safer-by-design and higher performance microbatteries (µBs) is also much-awaited to satisfy the increasing demand for miniaturized embarked electronics, e.g. to power Internet of Thing (IoT) objects with improved energy autonomy. Inorganic electrolytes are currently envisioned as the next generation electrolytes of choice for solid-state microbatteries (SSµBs). Nevertheless, they exhibit significant cons beyond their inherent pros. In particular, one cannot ensure the integrity and functionality of their key-enabling (solid-state electrolyte/electrodes) interfaces while the battery experiences internal strains (due to lithiation/delithiation processes) during cycling, leading to unpredictable and/or erratic performance' fluctuation up to spurious battery malfunction and ultimately failure.
To originally tackle this question, we propose in this international PhD research proposal (SHAPE jointly developed by JRU5279-LEPMI and IRL3463-LN2) to combine in a new generation of Self-Healing Polymer Electrolytes (designed, synthesized & characterized at LEPMI) with on-chip solid-state microbatteries (SSµBs assembled, characterized and cycled at LN2) relying on a porosified silicon (Si) negative electrode. We aim at (i) pushing the frontier of knowledge for on-chip energy storage (TRL1-3) and (ii) Proof-of-Concept (PoC) demonstrations (TRL3-4). Through the joint submission of beamtime proposals to large-scale facilities (e.g. Soleil and ESRF), the teams of the JRU5279-LEPMI and IRL3463-LN2 labs will join forces to perform in situ & operando X-ray scattering and imaging coupled witn electrochemical techniques of SHPEs thin films infiltrated within porous Si negative electrodes and SSµBs to allow for PoC demonstrations at the battery materials & energy storage device levels, respectively.
As a “chemistry neutral” (i.e. a 2.0 solution applying to mono/multi-valent cations-based batteries) and innovative blueprint for on-wafer SSµBs to power micro/nano-electronic devices, the advantages of SHPEs are sixfold: (i) their tunable-by-macromolecular design (ca)tionic (e.g. Li+) conductivity, (ii) their facilitated integration into micro/nano-fabrication processes , (iii) their light-weight attribute leading to energy-denser SSµBs, (iv) their inherent softness (viscoelastic nature), which can adapt battery materials to strain generated within operating device, (v) their self-healing properties to reshape battery materials within SSµBs though temperature cycles, benefiting from a bioinspired behavior encoded into their chemical structures, and (vi) enabling a physical parameter (Temperature) to control and regulate the State-of-Health (SoH) and State-of-Charge (SoC) of these SSµBs 2.0; thereby implementing a smart Battery Management System (BMS).
The first (materials) part of the SHAPE project will take place at the LEPMI laboratory and will focus on macromolecular engineering, synthesis and multi-scale/physics characterizations of structure/ionic transport properties of self-healing polymer electrolytes. In close collaboration with LEPMI, the second (device) part of the project will be developed at the LN2 Laboratory in Quebec where these polymer electrolytes will be melt-infiltrated into porosified silicon negative electrodes and assemblies of on-chip all-solid-state microbattery full cells will be produced, characterized and cycled to determine their performance and durability.

Contexte de travail

LEPMI (Laboratory of Electrochemistry and Physicochemistry of Materials and Interfaces) is a joint research unit (JRU5279) composed of staff from the French National Center for Scientific Research (CNRS), the Grenoble National Polytechnic Institute (Grenoble-INP), the University Grenoble Alps (UGA) and the University of Savoie Mont-Blanc (USMB). LEPMI's main research activities focus on the development and multi-scale/physics characterization of functional materials (polymers, salts, ionic liquids, catalysts, ceramics) intended for energetic systems (batteries, fuel cells, and solar cells).
The recruited person will work primarily within the Materials, Interfaces and ELectrochemistry (MIEL) team located on the UGA campus in Saint-Martin-d'Hères. This multidisciplinary team focuses on eco-design and chemical, electrochemical, physicochemical and physical characterizations of polymers, salts, ionic liquids and ionomers and electrolytes dedicated to the electrochemical storage and conversion of energy (batteries: lithium-polymer, lithium-ion, lithium-Sulfur, Na, Ca, Mg. Proton and alkaline polymer membrane fuel cells, perovskite-based solar cells). The MIEL team develops a sustained and innovative activity on in-situ and operando study by coupled techniques: Electrochemistry/Raman, Electrochemistry/NMR, Electrochemistry/X-ray diffusion, imaging and spectroscopy. The MIEL team is consisting of 19 permanent staff, 15 doctoral students/year, 4 postdocs/year and 6 masters/year. The work of the SHAPE project will be carried out in co-supervision and synergistic collaboration with the energy-on-chip team of the Nanotechnologies Nanosystems Laboratory, the international research laboratory IRL3463-LN2 based in Sherbrooke, Quebec. Scientific stays in Canada are an integral part of the research program of this thesis, which will be partly carried out in immersion within the rich scientific ecosystem of the Interdisciplinary Institute of Technological Innovation (3IT) and the infrastructures (clean rooms) and technological platforms of the MiQro Innovation Collaboration Center (C2MI) of the University of Sherbrooke (UdeS) where the on-chip solid-state microbatteries of the SHAPE project will be assembled, characterized and cycled.