Ion dynamics into different pore size distributions in supercapacitors under compression  

作　　者：João Pedro Aguiar dos Santos Cesar J.B.Pagan Rafael Vicentini Reinaldo F.Teófilo Renato Beraldo Leonardo M.Da Silva Hudson Zanin 

机构地区：[1]Brazilian Renewable Energies,Center for Innovation on New Energies,School of Electrical and Computer Engineering,University of Campinas,Av.Albert Einstein 40,Campinas,SP13083-852,Brazil [2]School of Electrical and Computer Engineering,University of Campinas,SP 13083-852,Brazil [3]Multivariate Chemical Data Analysis Laboratory,Department of Chemistry,Universidade Federal de Viçosa,36570-900 Viçosa,MG,Brazil [4]Department of Chemistry,Laboratory of Fundamental and Applied Electrochemistry,Federal University of Jequitinhonha and Mucuri's Valley,Rodovia MGT 367,km 583,5000 Alto da Jacuba,39100-000,Diamantina,MG,Brazil

出　　处：《Journal of Energy Chemistry》2023年第5期110-119,I0004,共11页能源化学（英文版）

基　　金：the financial support from the Brazilian funding agencies CNPq(301486/2016-6);FAPESP(2014/02163-7,2017/11958-1,2018/20756-6);the support from Shell。

摘　　要：Compressing supercapacitor(SCs)electrode is essential for improving the energy storage characteristics and minimizing ions’distance travel,faradaic reactions,and overall ohmic resistance.Studies comprising the ion dynamics in SC electrodes under compression are still rare.So,the ionic dynamics of five aqueous electrolytes in electrodes under compression were studied in this work for tracking electrochemical and structural changes under mechanical stress.A superionic state is formed when the electrode is compressed until the micropores match the dimensions with the electrolyte’s hydrated ion sizes,which increases the capacitance.If excessive compression is applied,the accessible pore regions decrease,and the capacitance drops.Hence,as the studied hydrated ions have different dimensions,the match between ion/pore sizes differs.To the LiOH and NaClO4electrolytes,increasing the pressure from 60 to 120 and 100 PSI raised the capacitance from 13.5 to 35.2 F g^(-1)and 30.9 to 39.0 F g^(-1),respectively.So,the KOH electrolyte with the lowest and LiCl with the biggest combination of hydrated ion size have their point of maximum capacitance(39.5 and 36.7F g^(-1))achieved at 140 and 80 PSI,respectively.To LiCl and KCl electrolytes,overcompression causes a drop in capacitance higher than 23%.

关 键 词：Mechanic compression Pore size distribution lon dynamics Activated carbon SUPERCAPACITORS 

分 类 号：TM53[电气工程—电器]