Innovative photocured polymer electrolyte membranes for efficient energy storage and conversion systems

In this communication, we present a summary of the most recent results of our Research Group regarding the preparation, physico-chemical and electrochemical characterization of PE membranes (salt-in-polymer or single-ion conductors) based on different methacrylic and/or EO-based oligomers with several kinds of additives, salts, plasticizers and fillers. We use UV and/or thermal induced free radical polymerisation to produce highly crosslinked fully amorphous PEs. Crosslinking allows the incorporation of high amounts of plasticiser and TFSI- based lithium salt, withstanding homogeneity and robustness. Thermal stability > 300 °C and high Young's modulus are achieved. Excellent ionic conductivity (> 5×10-4 S cm-1 at 25 °C), wide electrochemical window (>5 V vs. Li) and interfacial stability are envisaged, along with the ability to resist the lithium dendrite nucleation/growth. Remarkably stable ambient temperature cycling is demonstrated in lab-scale Li-/Na- or Li-S polymer cells at various C-rates with LiFePO4 and/or TiO2 electrodes. PE membranes are tested in dye-sensitized solar cells (DSSCs) upon proper modification. By introducing iodine/iodide-based redox mediator in the polymer matrix we achieve conversion efficiencies > 6% at 1 sun. Moreover, cobalt complexes are presented as high-potential redox mediator in quasi-solid DSSCs with stable-upon-time efficiencies. PEs and light-cured protective coatings are also demonstrated in photoelectrochromics for smart windows with highly stable characteristics and easy large scale manufacturing. In summary, we developed a portfolio of photopolymerized systems for multipurpose applications, the most recent outcome being the photochemical/environmental stabilization of perovskite solar cell