The development of highly conductive and safe electrolytes for sodium-ion batteries is an emerging field beyond lithium battery technologies. In this work we have developed new ionogel electrolytes consisting of a binary mixture of an organic ionic plastic crystal, N-ethyl-N-methylpyrrolidiniumbis(fluorosulfonyl)imide (C₂mpyrFSI), mixed with NaFSI supported on a mat of electrospun poly (vinylidene fluoride) nanofibers. The salt mixture near the eutectic composition (35 mol% NaFSI) was selected for further study after a detailed phase diagram analysis and ionogel electrolytes based on this were prepared. The ionic conductivity of the prepared ionogel composite reaches 2.6 10⁻³ S cm⁻¹ at ambient temperature. This ionogel membrane possessed a relatively high Na-ion transference number of 0.44 at 50 C and we demonstrate the performance of a Na metal full cell using a NaFePO₄ cathode (1.75–4.0 V). The assembled cells show a good capacity retention with coulombic efficiency close to 100% at various C rates between C/20, C/10 and C/5, achieving 120 mAh g⁻¹ at C/20. The long term charge/discharge performance is also demonstrated. Our study provides a feasible method to prepare highly conductive ionogel electrolytes for future Na-battery applications

开发用于钠离子电池的高导电性和安全电解质是锂电池技术之外的新兴领域。在这项工作中，我们开发了新的离子凝胶电解质，由有机离子塑料晶体、N-乙基-N-甲基吡咯烷鎓双（氟磺酰基）亚胺（C ₂ mpyrFSI）的二元混合物组成，与支撑在电纺聚（亚乙烯基）垫上的 NaFSI 混合。氟化物）纳米纤维。在详细的相图分析和基于此制备的离子凝胶电解质之后，选择接近共晶成分的盐混合物（35 mol% NaFSI）进行进一步研究。制备的离子凝胶复合材料的离子电导率达到2.6 10 ^-3 S cm ^-1在环境温度下。这种离子凝胶膜在 50 C 下具有相对较高的 0.44 的钠离子转移数，我们展示了使用 NaFePO ₄阴极（1.75-4.0 V）的钠金属全电池的性能。组装的电池在 C/20、C/10 和 C/5 之间的各种 C 倍率下显示出良好的容量保持率和接近 100% 的库仑效率，在 C/20 下达到 120 mAh g ^-1。还证明了长期充电/放电性能。我们的研究为制备用于未来钠电池应用的高导电离子凝胶电解质提供了一种可行的方法