摘要
In order to optimize and select the appropriate binder to improve the electrochemical performance of aqueous zinc-manganese batteries,the influences of water-soluble binders and oil-based binders on the zinc storage performance of manganese-based cathode materials were systematically investigated.The results show that the water-soluble binders with large numbers of hydroxyl and carboxyl groups are easily soluble in aqueous electrolytes,leading to poor electrochemical performance.Fortunately,the cathodes with polyvinylidene fluoride-hexafluoropropylene(PVDF-HFP)binder display high specific capacity of 264.9 mA·h/g and good capacity retention of 92%after 90 cycles at 100 mA/g.Meanwhile,PVDF-HFP binder with plenty of hydrophobic groups presents excellent ability in inhibiting cracks on the surface of electrode,reducing voltage polarization and charge transfer resistance,as well as maintaining electrode integrity.
为了优化和选择合适的黏结剂提高水系锌锰电池的电化学性能,系统地研究水溶性黏结剂和油性黏结剂对锰基正极材料储锌性能的影响。结果表明,含有大量羟基和羧基官能团的水溶性黏结剂易溶于水系电解液,导致较差的电化学性能。幸运的是,采用聚偏氟乙烯-六氟丙烯(PVDF-HFP)黏结剂制备的正极材料在电流密度为100 mA/g下循环90周后表现出264.9 mA·h/g的高比容量,容量保持率达到92%。与此同时,含有大量疏水性官能团的PVDF-HFP黏结剂在抑制电极表面裂纹、降低电压极化和电荷转移电阻、保持电极完整性方面表现出优异的能力。
基金
supported by the National Natural Science Foundation of China (Nos.51932011, 51972346)
the Hunan Natural Science Fund for Distinguished Young Scholar, China (No. 2021JJ10064)
the Program of Youth Talent Support for Hunan Province, China (No. 2020RC3011)
the Innovation-Driven Project of Central South University, China (No. 2020CX024)
