期刊
ELECTROCHIMICA ACTA
卷 85, 期 -, 页码 139-144出版社
PERGAMON-ELSEVIER SCIENCE LTD
DOI: 10.1016/j.electacta.2012.08.030
关键词
Energy storage; Electrical double layer capacitor; Ionic liquid; Organic solvent additive
资金
- Estonian Ministry of Education and Research [SF0180002s08]
- European Regional Development Fund [SLOKT10209T]
- Estonian Centre of Excellence [3.2.0101.11-0030]
- Estonian Science Foundation [8172]
The influence of small addition of acetonitrile (AN) (from 0.016 to 16 wt%) to 1-ethyl-3-methylimidazolium tetrafluoroborate (EMImBF(4)) electrolyte for electrical double layer capacitors (EDLCs), completed from two carbon cloth electrodes, has been studied using cyclic voltammetry, electrochemical impedance spectroscopy (EIS) and by modeling the EIS data with equivalent circuit. The addition of AN to the EMImBE(4) has strong influence on the bulk viscosity, conductivity and melting temperature of EMImBF(4), when more than 1.6 wt% of AN is added. Within the electrochemical stability region of EDLCs, the performance (gravimetric capacitance similar to 125 Fg(-1), characteristic relaxation time similar to 14 s, specific energy similar to 49 Wh kg(-1) or 12 Wh dm(-3), and specific power 28 kW kg(-1) or 7 kW dm(-3)) of the EDLCs based on EMImBF(4) and AN electrolyte is not improved when the addition of AN is from 0.033 to 3.3 wt%. However, the relaxation time is decreased to 8 s and specific power of EDLC is increased to 49 kW kg(-1), if 16 wt% of AN is added. More pronounced distortion effects and deviations from ideal capacitive behavior have been observed at higher applied potentials (3.2 V) when the addition of AN in the electrolyte of EDLC is higher than 3.3 wt%. The electrochemical stability of EDLC decreases through increase in the extent of faradaic reactions occurring at relatively high applied potentials, when larger amount of AN is added to the electrolyte EDLC. (C) 2012 Elsevier Ltd. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据