Research Progress on Optimization Strategies for Low-Temperature Performance of Sodium-Ion Batteries

Sodium-ion batteries (SIBs) have emerged as a highly promising candidate for large-scale energy storage and low-temperature (LT) applications, featuring abundant raw materials, low cost and working mechanisms analogous to lithium-ion batteries (LIBs). Although the ionic radius of Na⁺ is slightly larger than that of Li⁺, their smaller Stokes radius and lower desolvation energy barrier endow SIBs with unique thermodynamic advantages in LT environments. However, under extremely LT conditions, issues such as a sharp increase in electrolyte viscosity, sluggish desolvation kinetics, lattice distortion and detrimental phase transitions in electrode materials, as well as instability at the electrode-electrolyte interface, collectively constrain the LT electrochemical performance of SIBs. Most existing literature merely conduct fragmented and decoupled summaries focusing on a single component (electrolyte, cathode or anode), lacking systematic elucidation of the multi-factor coupled degradation mechanism under LT conditions and holistic evaluation of multi-dimensional modification strategies. To fill this research gap, this work systematically elaborates the intrinsic LT degradation mechanism of SIBs driven by multi-physical-field coupling. From four core perspectives, including electrolyte engineering, cathode modification, anode structural construction and precise interface regulation, we comprehensively summarize mainstream technical systems for LT performance enhancement at the current stage, and thoroughly analyze the working principle, technical merits and inherent limitations of various modification approaches. Finally, the future development directions of SIBs are prospected on the basis of previous research, aiming to provide systematic and scientific theoretical guidance for in-depth mechanism exploration and industrial technological upgrading of wide-temperature-range, high-performance SIBs.