Boosting energy-storage capability in carbon-based supercapacitors using low-temperature water-in-salt electrolytes

作     者：Joao Pedro A.Santos Manuel J.Pinzón érick A.Santos Rafael Vicentini Cesar J.B.Pagan Leonardo M.Da Silva Hudson Zanin Jo?o Pedro A.Santos;Manuel J.Pinzón;érick A.Santos;Rafael Vicentini;Cesar J.B.Pagan;Leonardo M.Da Silva;Hudson Zanin

作者机构：Brazilian Renewable EnergiesCenter for Innovation on New EnergiesSchool of Electrical and Computer EngineeringUniversity of CampinasSao Paulo 13083-852Brazil Department of SemiconductorsInstruments and PhotonicsSchool of Electrical and Computer EngineeringUniversity of CampinasSao Paulo 13083-852Brazil Laboratory of Fundamental and Applied ElectrochemistryDepartment of ChemistryFederal University of Jequitinhonha e Mucuri’s ValleyMinas Gerais 39100-000Brazil 

出 版 物：《Journal of Energy Chemistry》 (能源化学（英文版）)

年 卷 期：2022年第31卷第7期

页      面：521-530,I0013页

核心收录：

学科分类：0820[工学-石油与天然气工程] 080801[工学-电机与电器] 0808[工学-电气工程] 081704[工学-应用化学] 08[工学] 0817[工学-化学工程与技术] 0703[理学-化学] 

基　　金：the financial support from the Brazilian funding agencies CNPq(310544/2019-0),FAPESP(2014/02163-7&2017/11958-1) FAPEMIG(Financial support for the LMMA/UFVJM Laboratory)and CNPq(PQ-2 grant:Process 301095/2018-3) the support from Shell and the strategic importance of the support given by ANP(Brazil’s National Oil,Natural Gas,and Biofuels Agency)through the R&D levy regulation。 

主　　题：Carbon supercapacitors Water-in-salt electrolytes Low-temperature charge-storage Specific energy improvement at low temperatures 

摘      要：Supercapacitors(SCs) are high-power energy storage devices with ultra-fast charge/discharge properties.SCs using concentrated aqueous-based electrolytes can work at low temperatures due to their intrinsic properties, such as higher freezing point depression(FPD) and robustness. Besides the traditional organic-and aqueous-based(salt-in-water) electrolytes used in SCs, water-in-salt(WISE) sodium perchlorate electrolytes offer high FPD, non-flammability, and low-toxicity conditions, allowing the fabrication of safer, environmentally friendly, and more robust devices. For the first time, this work reports a comprehensive study regarding WISE system’s charge-storage capabilities and physicochemical properties under low-temperature conditions(T 0 ℃) using mesoporous carbon-based electrodes. The effect of temperature reduction on the electrolyte viscosity and electrical properties was investigated using different techniques and the in-situ(or operando) Raman spectroscopy under dynamic polarization conditions.The cell voltage, equivalent series resistance, and specific capacitance were investigated as a function of the temperature. The cell voltage(U) increased ~ 50%, while the specific capacitance decreased ~20%when the temperature was reduced from 25 ℃ to -10 ℃. As a result, the maximum specific energy(E = CU^(2)/2) increased ~ 100%. Therefore, low-temperature WISEs are promising candidates to improve the energy-storage characteristics in SCs.