RT Journal Article T1 Flexible solvent-free polymer electrolytes for solid-state Na batteries A1 Martínez Cisneros, Cynthia Susana A1 Pandit, Bidhan A1 Levenfeld Laredo, Belén A1 Lumbier Álvarez, Alejandro A1 Sánchez, Jean Yves AB Post-lithium batteries, based on alkaline and alkaline earth elements, are cheaper technologies with the potential to produce disruptive changes in the transition towards cleaner and sustainable energy sources less dependent on fossil fuels. This contribution deals with the development and characterization of sodium-conducting solvent-free polymer electrolytes towards the attainment of Sodium Polymer Batteries. Obtained via the polycondensation of α, ω-dihydroxy-oligo(oxyethylene) with an unsaturated dihalide, whose further curing leads to amorphous networked electrolyte films. Using NaClO4 and NaCF3SO3 at different O/Na ratios, the best polymer electrolyte reaches a cationic conductivity (σ+) exceeding 1 mS cm−1 at 90 °C whereas maintaining mechanical integrity up to at least 120 °C. PB Elsevier SN 0378-7753 YR 2023 FD 2023-03-01 LK https://hdl.handle.net/10016/38441 UL https://hdl.handle.net/10016/38441 LA eng NO The authors would like to thank the Agencia Española de Investigación/Fondo Europeo de Desarrollo Regional (FEDER/UE) for funding the project PID2019-106662RBC43.This work has been supported by the Madrid Government (Comunidad de Madrid-Spain) through three projects: 1) the Multiannual Agreement with UC3M ("Fostering Young Doctors Research", CIRENAICA-CM-UC3M), and in the context of the VPRICIT (Research and Technological Innovation Regional Programme); 2) the Multiannual agreement with UC3M ("Excelencia para el Profesorado Universitario" - EPUC3M04) - Fifth regional research plan 2016-2020; 3) DROMADER-CM (Y2020/NMT6584). B.P. and A.V. acknowledge support from the CONEX-Plus programme funded by Universidad Carlos III de Madrid and the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No. 801538. DS e-Archivo RD 1 sept. 2024