Electric and Temperature Field‐Modulated Periodic Repair of the Electrode/Electrolyte Interface toward Long Cycle Stability of Low‐Temperature Li‐Ion Batteries

This study tackles the poor low‐temperature performance of lithium‐ion batteries through a synergistic strategy that modulates electrode–electrolyte interfacial chemistry via coordinated temperature and electric field control. The research uncovers distinct interfacial evolution mechanisms: at −20 °C, strengthened solvent–Li + affinity causes solvation structure reorganization and interfacial deterioration, whereas at 25 °C, enhanced anion participation promotes formation of stable inorganic‐rich interphases. Reduced electric field intensity further facilitates the construction of stable interfaces. Based on these findings, a variable‐temperature constant‐current cycling protocol with periodic room‐temperature activation is developed. This approach effectively restores stable interfaces and substantially minimizes polarization, enabling commercial lithium iron phosphate (LFP) batteries to maintain nearly 100% initial capacity after 150 cycles at −20 °C—significantly surpassing conventional strategies (80.4% retention). Notably, this optimization method regulates interfacial chemistry through external field parameters without electrolyte formulation changes, demonstrating both theoretical innovation and engineering practicality. This work provides a novel paradigm for low‐temperature battery design by decoupling interfacial regulation from material modification.