Yahia Mohamed, Enterría Marina, Pozo-Gonzalo Cristina, Ortiz-Vitoriano Nagore
Center for Cooperative Research on Alternative Energies (CIC energiGUNE), Basque Research and Technology Alliance (BRTA), Alava Technology Park, Albert Einstein 48, Miñano, 01510, Spain.
Institute for Frontier Materials, Deakin University, Geelong, Victoria, 3200, Australia.
Adv Sci (Weinh). 2025 Aug;12(30):e04490. doi: 10.1002/advs.202504490. Epub 2025 May 23.
A novel quasi-solid polymer electrolyte (QSPE) composed of polyamide (PA) and polyethylene oxide (PEO), commercially known as Pebax1657, and combined with 1 M sodium bis(trifluoromethanesulfonyl)imide (NaTFSI) in diethylene glycol dimethyl ether (diglyme, DEGDME), has been investigated for sodium-oxygen (Na-O) batteries. Pebax1657 QSPE exhibits high ionic conductivity (6.57 × 10 S cm at room temprerature - RT), an oxidation onset potential of 4.69 V versus Na/Na⁺, and an enhanced Na⁺ transference number (t ≈ 0.40). Structural analysis (Raman spectroscopy, differential scanning calorimetry, X-ray diffraction, small-angle X-ray scattering) confirms reduced PEO crystallinity and formation of orderly nanodomains, facilitating Na⁺ transport. Long-term galvanostatic cycling in Na|Na symmetrical cells demonstrates stable overpotentials (≈80 mV) at 75 µA cm⁻ for 210 h, outperforming conventional liquid electrolytes (≈110 h). Pebax1657 QSPE enables higher discharge capacities (2.60 mAh cm⁻ at 75 µA cm⁻; 2.11 mAh cm⁻ at 150 µA cm⁻) with lower overpotentials (≈0.2 V). It sustains 25 cycles at 75 µA cm⁻ and 35 cycles at 150 µA cm⁻ at 0.25 mAh cm⁻, with a Coulombic Efficiency (CE) of 80-90%. Compared to the state of the art, Pebax1657 QSPE offers improved electrochemical stability, lower overpotentials, and better capacity retention. Its sustainability and versatility make it a strong candidate for Na-O batteries and other energy storage applications.
一种新型的准固态聚合物电解质（QSPE），由聚酰胺（PA）和聚环氧乙烷（PEO）组成，商品名为Pebax1657，并与1 M双（三氟甲磺酰）亚胺钠（NaTFSI）在二甘醇二甲醚（二甘醇二甲醚，DEGDME）中混合，已被用于钠氧（Na-O）电池的研究。Pebax1657 QSPE在室温下表现出高离子电导率（6.57×10 S cm），相对于Na/Na⁺的氧化起始电位为4.69 V，以及增强的Na⁺迁移数（t≈0.40）。结构分析（拉曼光谱、差示扫描量热法、X射线衍射、小角X射线散射）证实了PEO结晶度的降低和有序纳米域的形成，促进了Na⁺的传输。在Na|Na对称电池中的长期恒电流循环表明，在75 µA cm⁻下210小时内过电位稳定（≈80 mV），优于传统液体电解质（≈110小时）。Pebax1657 QSPE能够实现更高的放电容量（在75 µA cm⁻下为2.60 mAh cm⁻；在150 µA cm⁻下为2.11 mAh cm⁻），而过电位较低（≈约0.2 V）。在0.25 mAh cm⁻下，它在75 µA cm⁻下能维持25次循环，在150 µA cm⁻下能维持35次循环，库仑效率（CE）为80-90%。与现有技术相比，Pebax1657 QSPE具有更好的电化学稳定性、更低的过电位和更好的容量保持率。其可持续性和多功能性使其成为Na-O电池和其他储能应用的有力候选者。
