Advance Additive for High Voltage Capability and Superior Cycle Stability Sodium-Ion Battery

Sodium-ion batteries currently face two principal challenges. First, the large ionic radius of sodium slows down the kinetic processes, leading to suboptimal rate and cycling performance. Second, the standard electrode potential of sodium (−2.71 V vs SHE) is higher than that of lithium (−3.04 V vs SHE), which results in a reduced operating voltage for sodium-ion batteries. Incorporating additives is an effective strategy for forming a solid electrolyte interface (SEI) and a cathode electrolyte interface (CEI), which can significantly address these issues. Through a combination of physical characterization and theoretical calculations, it has been determined that 1,3-propane sultone (1,3-PS) can actively contribute to the formation of SEI and CEI due to its reductive potential and the energy of its Lowest Unoccupied Molecular Orbital (LUMO). The lower LUMO energy of 1,3-PS confers higher reduction potentials, enabling it to undergo reduction reactions on the anode surface and form a protective passivation film before the solvent decomposes. In addition, 1,3-PS can also prevent electrolyte oxidation and decomposition, thus improving battery inflation issues. 1,3-PS proved to improve performance for high voltage capability and superior cycle stability Sodium-ion battery, achieving of a 96.16% capacity retention and an 5.9% higher discharge specific capacity at 50 mA·g–1 than the half battery without the additive. NVP||HC punch battery was assembled with 1,3-PS of 1000 cycles plating/stripping, achieving a better capacity retention and antioxidant capacity as compared to the punch battery with the blank electrolyte.