东华大学朱美芳课题组取得一项新突破。他们提出了通过引入阴离子锚定分离器增强钠离子电池的稳健性和电荷转移动力学。2025年3月4日出版的《美国化学会杂志》发表了这项成果。

研究小组提出了一种阴离子锚定策略来增强Na⁺运输动力学，该策略基于引入具有正表面电位的分离器。

此外，研究组开发了一种核磁共振辅助的Hittorf方法，以解决传统Bruce-Vincent方法本身的局限性，以便在时间尺度上准确量化阴离子的迁移动态。结果表明，该策略有效地锚定了游离阴离子，增加了体中溶剂分离离子对的比例，降低了阳极的阳离子转移能垒，减轻了阴极的寄生反应。对称Na||Na电池在1600 h内有效工作，而Na||Na₃V₂(PO₄)₃电池在有限钠过量和贫电解质条件下具有稳定的循环性能。组装的HC||Na₃V₂(PO₄)₃袋电池的能量密度高达225.7 W h kg^-1。他们的策略为高能量和长周期钠离子电池提供了新的选择。

据介绍，离子输运对电池的性能起着至关重要的作用。

附：英文原文

Title: Enhancing Robustness and Charge Transfer Kinetics of Sodium-Ion Batteries through Introduction of Anionic Anchoring Separators

Author: Xiao Li, Tao Zhang, Yilin Zhao, Xiaoqing Zhu, Aimin Ge, Keith C. Gordon, Fei Wang, Guiyin Xu, Meifang Zhu

Issue&Volume: March 4, 2025

Abstract: Ionic transport critically dictates the performance of the batteries. Here, we proposed an anion anchoring strategy for enhancing Na⁺ transport kinetics that was based on introducing a separator with a positive surface potential. Besides, we developed a nuclear magnetic resonance-assisted Hittorf approach to address the limitation of the traditional Bruce–Vincent approach itself in order to accurately quantify the migration dynamics of anions on the time scale. Results indicate that this strategy effectively anchors free anions and increases the proportion of solvent-separated ion pairs in the bulk, reduces the cation transfer energy barrier at the anode, and mitigates parasitic reactions at the cathode. The symmetric Na||Na cells efficiently operate over 1600 h, and the Na||Na₃V₂(PO₄)₃ cells show stable cycling performance under limited Na excess and lean electrolyte conditions. The assembled HC||Na₃V₂(PO₄)₃ pouch cells achieve an energy density of up to 225.7 W h kg^–1. Our strategy offers a new option for high-energy and long-cycle sodium-ion batteries.

DOI: 10.1021/jacs.4c16227

Source: https://pubs.acs.org/doi/abs/10.1021/jacs.4c16227