Aqueous Supercapacitors With Wide Operative Voltage Window and Long Cycling Life Enabled by Electrolyte Hybridization Effect  

电解质杂化效应衍生的高性能水系超级电容器

作　　者：Shi-Hua Ma Qi Yin Jin-Ping Zhao 马世花;尹起;赵金平(烟台南山学院,科技与数据学院,山东烟台265713;山东理工大学,化学化学工程学院,山东淄博255000)

机构地区：[1]College of Technology and Date,Yantai Nanshan University,China [2]School of Chemistry and Chemical Engineering,Shandong University of Technology,Zibo,Shandong,255049,China

出　　处：《电化学（中英文）》2024年第11期27-36,共10页Journal of Electrochemistry

基　　金：supported by the Longkou City Science and Technology Research and Development Plan(No.2020KJJH061).

摘　　要：Developing supercapacitors(SCs)with long cycling life and wide operative voltage window is a significant topic in the field of aqueous electrolytes.Although the design of water in salt(WIS)electrolytes has pushed the development of aqueous electrolytes to a new height,the WIS electrolytes with an operative voltage window of up to 2.5 V is still very scarce.Herein,in order to enrich the type of aqueous electrolyte with high operative voltage,tetramethylammonium trifluoromethanesulfonate(TMAOTf)based WIS electrolyte was used as a model to construct WIS based hybrid electrolyte with acetonitrile(ACN)co-solvent and LiTFSI co-solute.In view of the coordination effect of ACN and Lit on free water in TMAOTf based WIS electrolyte,the TMAt-Lit-AWIS electrolyte has the electrochemical stabilization window of up to 3.35 V.Further coupled with the commercial YP-50F electrodes,TMAt-Lit-AWIS based SCs exhibited wide operative voltage window(2.5 V),long cycling life(45,000 cycles)and good low-temperature performance(99.99%capacitance retention after 2000 cycles at20℃).The design of this hybrid electrolyte will enrich the types of aqueous hybrid electrolytes with long cycling life and wide operative voltage window.水系超级电容器具有快速充放电特性,已经成为一种重要的电化学储能器件。然而,它们的应用受到了较窄电压窗口的制约。尽管近年来盐包水(WIS)电解质的设计已显著克服了这一应用缺陷,但工作电压窗口高达2.5 V的WIS体系仍然非常稀缺。为了丰富超级电容器所用高压水系电解质的类型,本文基于三氟甲烷磺酸四甲基铵盐(TMAOTf)的电化学惰性,报道了一种由TMAOTf、双三氟甲基磺酸亚酰胺锂(LiTFSI)、水(H_(2)O)和乙腈(ACN)组成的TMAOTf基杂化电解质,鉴于ACN对自由水的配位效应、Li^(+)的溶剂化效应以及TFSI-的化学惰性,TMAOTf基杂化电解质展现出优良的非燃特性,且其电化学稳定窗口(3.35 V)远比目前所报道经典WIS电解质的要宽。进一步将这种杂化电解质与商业活性炭电极(YP-50F)所匹配,所构筑的水系超级电容器能够输出宽的工作电压窗口(2.5 V)、高的倍率性能(10A·g^(-1)下的容量保持率为80%)、长的循环寿命(45,000次循环)和优异的低温性能(-20℃下循环2000次的容量保留率为99.99%),克服了水系超级电容器电压窗口与循环寿命的冲突。因此,这种TMAOTf基复合水系电解质的设计不仅丰富了具有长循环寿命和高工作电压窗口水系超级电容器的类型,也证明了电解质杂化策略对构筑高性能储能器件的有效性,为碳中和目标的实现蓄势赋能。

关 键 词：Supercapacitor Aqueous hybrid electrolyte Tetramethylammonium trifluoromethanesulfonate based water in salt electrolyte Operative voltage window Cycling life 

分 类 号：O646[理学—物理化学] TM53[理学—化学]