Wang Yumei, Wang Zhongting, Xu Xiaoyu, Oh Sam Jin An, Sun Jianguo, Zheng Feng, Lu Xiao, Xu Chaohe, Yan Binggong, Huang Guangsheng, Lu Li
College of Aerospace Engineering, Chongqing University, Chongqing, 400044, People's Republic of China.
National University of Singapore (Chongqing) Research Institute, Chongqing, 401123, People's Republic of China.
Nanomicro Lett. 2024 Jul 25;16(1):254. doi: 10.1007/s40820-024-01474-6.
Symmetric Na-ion cells using the NASICON-structured electrodes could simplify the manufacturing process, reduce the cost, facilitate the recycling post-process, and thus attractive in the field of large-scale stationary energy storage. However, the long-term cycling performance of such batteries is usually poor. This investigation reveals the unavoidable side reactions between the NASICON-type NaV(PO) (NVP) anode and the commercial liquid electrolyte, leading to serious capacity fading in the symmetric NVP//NVP cells. To resolve this issue, an all-solid-state composite electrolyte is used to replace the liquid electrolyte so that to overcome the side reaction and achieve high anode/electrolyte interfacial stability. The ferroelectric engineering could further improve the interfacial ion conduction, effectively reducing the electrode/electrolyte interfacial resistances. The NVP//NVP cell using the ferroelectric-engineered composite electrolyte can achieve a capacity retention of 86.4% after 650 cycles. Furthermore, the electrolyte can also be used to match the Prussian-blue cathode NaFeFe(CN)·nHO (NFFCN). Outstanding long-term cycling stability has been obtained in the all-solid-state NVP//NFFCN cell over 9000 cycles at a current density of 500 mA g, with a fading rate as low as 0.005% per cycle.
使用NASICON结构电极的对称钠离子电池可以简化制造工艺、降低成本、便于回收后处理，因此在大规模固定储能领域具有吸引力。然而，这类电池的长期循环性能通常较差。本研究揭示了NASICON型NaV(PO)（NVP）负极与商用液体电解质之间不可避免的副反应，导致对称NVP//NVP电池中严重的容量衰减。为了解决这个问题，使用全固态复合电解质来替代液体电解质，从而克服副反应并实现高的负极/电解质界面稳定性。铁电工程可以进一步改善界面离子传导，有效降低电极/电解质界面电阻。使用铁电工程复合电解质的NVP//NVP电池在650次循环后可实现86.4%的容量保持率。此外，该电解质还可用于匹配普鲁士蓝正极NaFeFe(CN)·nHO（NFFCN）。全固态NVP//NFFCN电池在500 mA g的电流密度下经过9000次循环获得了出色的长期循环稳定性，每循环的衰减率低至0.005%。
