PhD in Polymer chemistry: Development of new polymer membranes for Zn/Manganate-Permanganate hybrid...

In the current scenario of energy transition, large-scale energy storage requires low-cost batteries, with high safety, low maintenance, a number of charge/discharge cycles, as well as, for certain services, a high power. Redox Flow (RFB) batteries are particularly well suited to meet these requirements as they cover a power/energy range from a few kW/kWh to tens of MW/MWh and are designed for longer storage periods than most other storage technologies.

In this context, research on new cellular configurations, in particular the identification of new redox couples as well as the membrane separating them, is still necessary. Indeed, this ion exchange membrane remains one of the critical components of BFRs. In addition to ensuring the selective transfer of ions from one compartment to the other to balance the charge, it must prevent the compounds of the two electrolytic compartments from mixing (crossover) in order to avoid short circuits or self-discharges.

This PhD subject, part of a collaborative project with industrial partners (EDF, Sunergy), aims to develop an exchange membrane for an aqueous Zinc/Manganate-Permanganate hybrid Redox-Flow battery. It must have excellent chemical stability with respect to oxidizing agents, low ionic resistance, high selectivity with respect to ions, while being impermeable to electrolytes and mechanical strength suitable for the application.

Several lines of work will be carried out during this thesis project, in particular:

- The identification, from existing commercial membranes, of the key parameters governing the properties of interest (ionic conductivity, selectivity, porosity, etc.) for the redox flow application.

- The development of new polymer materials or the chemical modification of commercial separators. All the properties (physico-chemical, mechanical, chemical stability in an oxidizie environment, etc.) of the membranes obtained will be evaluated.

- When a material is identified as promising, it will be tested in a battery under the envisaged conditions and then transferred to industrial partners for the insertion in the final prototype.