Sodium-ion batteries (SIBs) are being aggressively pursued for potential use in energy storage systems due to the natural abundance and low cost of sodium. In the present investigation, structural, thermal and electrochemical properties of a ionic liquid based Na-ion conducting polymer-salt-IL electrolytes (IL-NCPEs) formed using copolymer poly(vinylidene fluoride-co-hexafluoropropylene) (PVdF-HFP), sodium bis(trifluoromethanesulfonyl)imide (NaTFSI) salt along with IL; 1-butyl-1-methypyrrolidinium bis(trifluoromethanesulfonyl)imide ([BMPYr] [TFSI]) is being reported. The samples were characterized using ionic conductivity, transference number measurement, thermal & electrochemical studies as a function of wt% IL. Incorporated [BMPYr][TFSI]-IL in the NCPE (i.e., PVdF-HFP + 10 wt% NaTFSI) modifies the different physicochemical properties such as complex formation, thermal, transport and electrochemical properties. The ionic conductivity of prepared IL-NCPEs has been found to increase with increasing the content of [BMPYr][TFSI]-IL and reaches to a maximum value of ∼0.85 mS/cm (at 30 °C). Also, the temperature dependent ionic conductivity obeys Arrhenius type thermally activated behaviour. For the optimized [BMPYr][TFSI]-IL, compatibility of IL-NCPEs with Na-metal electrode, high total ionic transference number (t_ionic ∼ 0.98), cationic transference number (t_Na⁺ ∼ 0.31) and wide electrochemical stability (ESW ∼ 4.0 V) have been obtained. The above obtained properties of the prepared IL-NCPEs are promising for application in Na-rechargeable battery.

由于钠的天然储量丰富且成本低廉，钠离子电池（SIB）正在积极寻求在储能系统中的潜在应用。在本研究中，使用聚偏二氟乙烯-六氟丙烯共聚物（PVdF-HFP）形成的基于离子液体的钠离子导电聚合物盐-IL电解质（IL-NCPE）的结构、热和电化学性质，双(三氟甲磺酰)亚胺钠 (NaTFSI) 盐以及 IL；1-丁基-1-甲基吡咯烷鎓双(三氟甲磺酰基)亚胺 ([BMPYr] [TFSI]) 正在被报道。使用离子电导率、迁移数测量、热和电化学研究（作为 wt% IL 的函数）对样品进行表征。在 NCPE 中掺入 [BMPYr][TFSI]-IL（即 PVdF-HFP + 10 wt% NaTFSI）可改变不同的物理化学性质，例如复合物形成、热、传输和电化学性质。研究发现，制备的 IL-NCPE 的离子电导率随着 [BMPYr][TFSI]-IL 含量的增加而增加，并达到最大值 ~0.85 mS/cm（30 °C 时）。此外，温度依赖性离子电导率遵循阿伦尼乌斯型热激活行为。对于优化的[BMPYr][TFSI]-IL，IL-NCPE与Na-金属电极的兼容性、高总离子迁移数（t _ionic  ∼ 0.98）、阳离子迁移数（t _Na ⁺  ∼ 0.31）和宽电化学稳定性（ ESW ∼ 4.0  V ) 已获得。所制备的 IL-NCPE 的上述性能有望在钠离子充电电池中得到应用。