TOPIC #11
Iron-based mixed phosphate/sulfate positive electrode materials for Na-ion batteries
Research area: Post Li-Ion Technologies, New Materials & Electrolytes
Keywords: Na-ion batteries; positive electrode materials; mixed polyanionic materials; phosphates; sulfates; NaSICON; Alluaudites; abundant elements
Supervising team: Laurence CROGUENNEC (UB), Loic SIMONIN (CEA) & Yohan BIECHER (CEA)
Abstract
Na-ion batteries are among the most promising battery technologies to overcome the issue of critical and/or scarce elements used in Li-ion batteries (cobalt, nickel, lithium, copper, etc.). However, although it has been proven that we could get rid of copper and lithium, it appears a lot more challenging to do without critical electroactive Transition Metal Elements (TME). Only three of these elements appear to be unquestionably abundant: iron, manganese and titanium.
The French laboratories ICMCB (Bordeaux) and LRCS (Amiens) have a very long-lasting experience
(~30 years) in the crystal chemistry of energy storage materials and in the characterization of mechanisms involved in materials at the forefront of key battery technologies. CEA-LITEN has developed over the last 20 years one of the most dynamic battery R&D and technological transfer platforms in Europe. These three groups have successfully participated in the development of a new Na-ion battery technology using the polyanionic material Na3V2(PO4)2F3 at the positive electrode, and delivering an energy density as high as 140 Wh/kg in full cell when combined with hard carbon. The second generation of this system is today developed by the spinoff company TIAMAT, and must be focused on the replacement of vanadium with non-critical elements. Moreover, in the frame of the former DESTINY project, our groups have collaborated to develop new iron-based mixed polyanion materials (sulphate and/or phosphate) with promising performances and high-level structural studies leading to publication of several patents and publications.
The first objective of this new PhD project is to go deeper in the understanding of the properties and optimisation of the performance of these materials. The second objective is to prospect on new compositions and structures. The PhD candidate will be in CEA-LITEN at Grenoble during the first year, and then in ICMCB at Bordeaux with short stays in Amiens for specific use of characterization techniques.
Interest for the student
Expected mobility:
The team is composed of Laurence Croguennec and Jacob Olchowka in ICMCB Bordeaux, Christian Masquelier in LRCS Amiens and Loïc Simonin and Yohan Biecher at CEA Liten. The parties have all agreed on the foreseen mobility track:
• Y1-M1 to Y1-M12: Year 1 spent in CEA Liten Grenoble for (i) the optimization of the synthesis process of compositions of interest identified during Anastasia Grebenshchikova’s PhD thesis and (ii) the optimization of electrode formulation to obtain reliable electrochemical performance in full cells upon long range cycling at different C-rates. The formation of composites with carbon additives and new mixed ionic and electronic conductive binders will be especially critical.
• Y2-M13 to M30: Year 2 and 1st semester of Year 3 spent mainly in ICMCB Bordeaux for (i) the advanced characterization of the structural, redox and surface mechanisms involved upon cycling of full cells and (ii) exploration of new mixed phosphate and sulfate compounds with optimized stability under air. Short stays will be performed in CEA-LITEN in Grenoble and in LRCS in Amiens.
• Y3-M31 to Y3-M36: 6 months of Year 3 spent in ICMCB Bordeaux for writing the PhD thesis to be defended in ICMCB Bordeaux.
Career opportunities: The project is related to the design of new sustainable positive electrode materials for the development of the next generation of Na-ion batteries. Therefore, it is both “fundamental” and “technological”, both “academic” (ICMCB and LRCS CNRS Laboratories) and “industry-related” (CEA Liten, a battery R&D and technological transfer platform). This creates a unique opportunity for the PhD student to have a flavour of both “worlds” added to the fact that she/he will be also immerged in the working environment of large-scale facilities with ILL and ESRF in Grenoble, Soleil in Gif/Yvette and Alba in Barcelona.
Additionally, the partners have long lasting collaboration records and belong to European research networks and initiatives, such as the ALISTORE-ERI European network (5 Companies, 32 Academic Laboratories) and the French RS2E (Réseau français sur le Stockage Electrochimique de l’Energie, 18 Companies, 17 Laboratories, 3 EPICS). Finally, the three groups were involved in the creation of the spin-off company TIAMAT. This generates fantastic opportunities for the PhD candidate enrolled in our Laboratories to meet people (established researchers in academia and industry, many PhD students), to share her/his results with the academic and industrial communities. This is essential for the future academic/enterprise career development and an important source of future collaborations within R&D&I projects. The PhD candidate will hence participate in an advanced PhD training within Europe, in the frame of longer term initiatives such as “BATTERY 2030+” and “Batteries Europe”. Indeed, many universities, institutes, and industries collaborate throughout several European projects.
Although this project is focused on battery materials, we believe that the tools and methodologies learned by the students will be valuable for many other application fields. Material science in general is at the heart of innovation in lots of technologies, and there will be always the need for highly trained PhD candidates.
Overall, as witnessed by the actual professional activities of our recent PhD graduates, prospects for career in Industry are high (Arkema, BASF, Stellantis, Renault, Saft, Saint-Gobain, Solvay, Umicore …). Few of our ex-students embarked in Academia even though several of them would have strong chances, thanks to highly achievements in terms of papers published and conferences given (Matteo BIANCHINI, Edouard BOIVIN and Long NGUYEN for instance, who all won several PhD Awards, national and international).
