Kang Jieun, Lee Inhui, Yu Gwonho, Heo Jin Jun, Choi Yuri, Lee Sangyeop, Kim Sungho, Kim Dongjoo, Ryu Jungki, Back Seoin, Park Soojin, Ryu Jaegeon
Department of Chemistry and Department of Battery Engineering, Pohang University of Science and Technology (POSTECH), Pohang, 37673, Republic of Korea.
School of Energy and Chemical Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan, 44919, Republic of Korea.
Adv Sci (Weinh). 2025 Jul 11:e05982. doi: 10.1002/advs.202505982.
Electrolytes shape solvation structures that govern ionic transport, stability, and interfacial properties in energy storage systems. Sodium-based dual-ion shuttling systems offer high-voltage and fast-charging potential but face challenges such as solvent co-intercalation, electrolyte decomposition, and low Coulombic efficiency, partly due to limited anion-focused electrolyte design. Herein, a low-concentration dual-ionic weakly solvating electrolyte (DWSE) is introduced, leveraging functionalized nano-graphene oxide additives to modulate the solvation environments of Na and PF . While a conventional cationic weakly solvating electrolyte (CWSE) enhances Na transport, DWSE simultaneously addresses anion and cation transport for a more balanced approach. DWSE prevents solvent co-intercalation, stabilizes interfaces with NaF-rich layers, and enhances ionic transport. It achieves a reversible capacity of 82.0 mAh g at 50 C and retains 96.2% capacity after 1500 cycles at 10 C. This study offers a robust framework for advancing dual-ion shuttling systems with optimized cation and anion dynamics.
电解质形成的溶剂化结构决定了储能系统中的离子传输、稳定性和界面性质。基于钠的双离子穿梭系统具有高电压和快速充电潜力，但面临着诸如溶剂共嵌入、电解质分解和低库仑效率等挑战，部分原因是阴离子聚焦的电解质设计有限。在此，引入了一种低浓度双离子弱溶剂化电解质（DWSE），利用功能化氧化石墨烯添加剂来调节Na和PF的溶剂化环境。虽然传统的阳离子弱溶剂化电解质（CWSE）增强了Na传输，但DWSE同时解决了阴离子和阳离子传输问题，采用了更平衡的方法。DWSE可防止溶剂共嵌入，稳定富含NaF层的界面，并增强离子传输。它在50℃时实现了82.0 mAh g的可逆容量，并在10℃下1500次循环后保留了96.2%的容量。本研究为推进具有优化阳离子和阴离子动力学的双离子穿梭系统提供了一个强大的框架。
