Polymer electrolytes for potassium batteries in the SYNERGY project framework

SYNERGY European project aims to strengthen the scientific and technical competences at the involved Portuguese institutions (PT Cluster) in the field of energy harvesting and micropower management, as a key component towards self-sustainable smart platforms on flexible substrates. Among the most in-vogue electrochemical energy technologies, the contribution from Politecnico di Torino also includes the development of advanced materials for potassium-based batteries. In this contribution, we present our recently started work focused on polymer electrolytes to replace unsafe and unstable liquid-state systems. Indeed, the high reactivity of alkali metals, like lithium and potassium, also interfacing with electrolytes, causes the unavoidable creation of the SEI layer, which is very likely to be fragile and heterogenous, causing the dendrites formation and eventually the failure of the cell. Gel polymer electrolytes (GPE) have been already proven to suppress dendrites growth thanks to their higher shear modulus. A BMA-co-PEGDA UV-cured system incorporating a plasticizer is here fully characterized and proposed as gel-polymer electrolyte for potassium-based batteries, showing outstanding ionic conductivity, excellent capacity retention in lab-scale cell prototypes and very good performances for more than 500 cycles.