The practical application of room-temperature Na-S batteries is hindered by the low sulfur utilization, inadequate rate capability and poor cycling performance. To circumvent these issues, here, we propose an electrocatalyst composite material comprising of N-doped nanocarbon and Fe3N. The multilayered porous network of the carbon accommodates large amounts of sulfur, decreases the detrimental effect of volume expansion, and stabilizes the electrodes structure during cycling. Experimental and theoretical results testify the Fe3N affinity to sodium polysulfides via Na-N and Fe-S bonds, leading to strong adsorption and fast dissociation of sodium polysulfides. With a sulfur content of 85 wt.%, the positive electrode tested at room-temperature in non-aqueous Na metal coin cell configuration delivers a reversible capacity of about 1165 mA h g−1 at 167.5 mA g−1, satisfactory rate capability and stable capacity of about 696 mA h g−1 for 2800 cycles at 8375 mA g−1.

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The advancements of lithium‐ion batteries indubitably call for advanced electrolytes with superior environmental adaptability and long‐term stability. Propylene carbonate (PC) proves to be a competitive solvent with the high permittivity and wide‐liquid range, while the application is intrinsically hindered by the poor graphite compatibility and high viscosity. Here, a PC‐based electrolyte with wide‐temperature range is developed by tuning the strength and topology of the Li+‐PC interactions via non‐solvating interactions without altering the solvation structure. Thus, the problem of graphite exfoliation caused by Li+‐PC co‐intercalation can be successfully mitigated. Consequently, such electrolyte shows compatibility with both graphite and high‐nickel cathode, exhibiting an expanded liquid range from −90 to 90 °C. This work, breaking from the traditional EC‐based formula, provides a new strategy for designing PC‐enabled electrolyte featuring high performance, wide‐temperature compatibility, and sustainability

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Developing advanced electrolytes proves indispensable for next-generation lithium-ion batteries (LIBs). Yet the strong solvating interaction between Li+ and various solvents often leads to sluggish desolvation and solvent co-intercalation into graphite...