Work

Dynamic molecular docking enables high-safety Na-ion pouch cells at elevated temperature

Year: 2025

Type: article

Abstract: Ensuring stable and safe operation of Na-ion batteries (NIBs) at high temperatures is a significant challenge for their practical use, which is limited by severe degradation of electrode materials and interfacial chemistries. In this study, we designed a novel electrolyte with excellent high-temperature tolerance, non-flammability, and a wide voltage window enabled by dynamic molecular docking between optimal solvent molecules. Such effect in a mixture of TEP-PC-PhCF 3 enables the outstanding capability to dynamically organize free solvents around Na + and meanwhile reframe microscopic solvation structures with macroscopically electrochemical stability. The designed electrolyte achieves a wide voltage window above 6 V vs. Na at room temperature and high-temperature of 55 °C. Dynamic molecular docking solvation induces NaF-enriched interfacial layers at a regular salt concentration, effectively suppressing irreversible phase transitions and gas generation in oxide cathodes and mitigating harmful Na plating in hard carbon anodes as well. A pouch cell with O3-type oxide cathode and hard carbon anode achieves stable cycling over 1000 cycles at 55 °C with a high-capacity retention of 86.9 % with greatly reduced gas generation. This work provides a new strategy for designing high-temperature-tolerant and intrinsically safe NIBs.

Source: Energy storage materials

DOI: 10.1016/j.ensm.2025.104733