Despite their beneficial effect on battery safety, non-flammable electrolytes often have an adverse side effect on the electrochemical performance of lithium and sodium ion batteries due to their poor compatibility with the electrodes. In this paper, we report a new non-flammable electrolyte consisting of trimethyl phosphate (TMP) and 1,1,2,2-tetrafluoroethy l-2,2,3,3-tetrafluoropropyl ether (F-EPE) as non-flammable solvents and fluoroethylene carbonate (FEC) as additive with different concentration of Na salts, and a EC-DEC-FEC electrolyte was also prepared as baseline electrolyte. The flammability and non-flammability of the prepared electrolytes was tested. It is shown that the prepared electrolyte not only increases the capacity (129.9 vs. 122.5 mAh g⁻¹ of baseline electrolyte) of NaNi_1/3Fe_1/3Mn_1/3O₂ (NFM) cathode but also stabilizes the cyclability (70.8% retention after 500 cycles) of NFM/HC (HC: hard carbon) pouch cells. The dissolution of pristine NaNi_1/3Fe_1/3Mn_1/3O₂ cathode material in different solvents and electrolytes, and the XPS patterns of the cycled NFM cathode in the prepared electrolytes were also studied to understand the capacity fading mechanism. These results indicate that this new non-flammable electrolyte holds great potential for application in rechargeable sodium-ion batteries.

尽管它们对电池安全性有有益的作用，但由于不可燃电解质与锂和钠离子电池的不良相容性，它们经常对锂和钠离子电池的电化学性能产生不利的副作用。在本文中，我们报告了一种由三甲基磷酸酯（TMP）和1,1,2,2-四氟乙基1-2,2,3,3-四氟丙基醚（F-EPE）组成的新型不易燃电解质溶剂和碳酸氟乙烯酯（FEC）作为具有不同浓度Na盐的添加剂，还制备了EC-DEC-FEC电解质作为基线电解质。测试了所制备电解质的可燃性和不可燃性。结果表明，所制备的电解质不仅增加了NaNi _1/3的容量（129.9 vs. 122.5 mAh g ^-1基线电解质）Fe _1/3 Mn _1/3 O ₂（NFM）阴极，但也稳定了NFM / HC（HC：硬碳）袋式电池的循环能力（500个循环后保持70.8％的保留率）。还研究了原始NaNi _1/3 Fe _1/3 Mn _1/3 O ₂正极材料在不同溶剂和电解质中的溶解情况，以及循环NFM正极在制备的电解质中的XPS模式，以了解容量衰减机理。这些结果表明，这种新型的非易燃电解质在可充电钠离子电池中具有巨大的应用潜力。