Fan Weizhen, Wang Wenlian, Xie Qixing, He Xin, Li Haijia, Zhao Jingwei, Nan Junmin
School of Chemistry, South China Normal University, Guangzhou, 510006, P.R. China.
Guangzhou Tinci Materials Technology Co., Ltd., Guangzhou, 510760, P. R. China.
Chemistry. 2024 Aug 1;30(43):e202401321. doi: 10.1002/chem.202401321. Epub 2024 Jul 12.
A sodium bis(fluorosulfonyl)imide (NaFSI)-based multifunctional electrolyte is developed by partially replacing NaPF salt in the electrolyte to improve the wide temperature range working capability of NaNiFeMnO/hard carbon (NNFM111/HC) sodium-ion batteries (SIBs). The capacity retention of the SIBs with NaFSI-NaPF dual salt electrolyte increases from 47.2 % to 75.5 % after 250 cycles at 25 °C, and from 51.0 % to 82.3 % after 80 cycles at 45 °C, and the 1 C discharge capacity retention at the low temperature of -20 °C also increases 26.8 %. In the single salt system, NaPF effectively passivate the aluminum foil and NaFSI passivate the electrode/electrolyte interface. The synergistic effect of NaPF and NaFSI greatly improves the battery performance in a wide temperature range. This NaFSI-based dual salt electrolyte also effectively overcomes the flaws when the SIBs using NaFSI or NaPF independently, and makes it more suitable for SIBs, indicating promising prospects in the commercial application of NNFM111/HC SIBs.
通过部分替代电解质中的NaPF盐，开发了一种基于双（氟磺酰）亚胺钠（NaFSI）的多功能电解质，以提高NaNiFeMnO/硬碳（NNFM111/HC）钠离子电池（SIB）在宽温度范围内的工作能力。使用NaFSI-NaPF双盐电解质的SIB在25℃下经过250次循环后，容量保持率从47.2%提高到75.5%，在45℃下经过80次循环后，从51.0%提高到82.3%，在-20℃低温下的1C放电容量保持率也提高了26.8%。在单盐体系中，NaPF有效地钝化铝箔，NaFSI钝化电极/电解质界面。NaPF和NaFSI的协同效应极大地提高了电池在宽温度范围内的性能。这种基于NaFSI的双盐电解质还有效地克服了单独使用NaFSI或NaPF的SIB的缺陷，使其更适合SIB，这表明NNFM111/HC SIB在商业应用中具有广阔前景。
