Design considerations for ionic liquid based electrochemical double layer capacitors

Autor(es)

Martins, Vitor L. ^{[1, 2]} ; Torresi, Roberto M. ^[1] ; Rennie, Anthony J. R. ^[2]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Inst Quim, Dept Quim Fundamental, Ave Prof Lineu Prestes 748, BR-05508000 Sao Paulo, SP - Brazil

^[2] Univ Sheffield, Chem & Biol Engn, Sir Robert Hadfield Bldg, Mappin St, Sheffield S1 3JD, S Yorkshire - England

• Tipo de documento: Artigo Científico
• Fonte: Electrochimica Acta; v. 270, p. 453-460, APR 20 2018.
• Citações Web of Science: 6

Resumo

A critical parameter in the design of EDLCs is the determination of electrochemical stability limits for individual combinations of electrode and electrolyte. Using {[}EMIm]{[}BF4] as an example we demonstrate that the physical properties of the activated carbon used in the electrodes influence the permissible operating potential of an EDLC, and also that the binder material employed can have further effects. When {[}EMIm]{[}BF4] electrolyte is coupled with electrodes containing PTFE binder, operating potentials as wide as 3.8 V can be utilised. Due to the differences in response under opposing polarisations, it is necessary to employ an asymmetric mass loading in EDLC cells in order to make full use of the operating window. By balancing the charge in the cell, the differences in stable potential limits and capacitative behaviour can be overcome, however we also found that this balance can be influenced by the rate at which these parameters are determined. Three-electrode measurements show that using an appropriate mass loading ratio results in each electrode operating within their determined stability limits. Stable cycling of a full cell at an operating potential of 3.8 V was demonstrated over 50,000 cycles. (C) 2018 Elsevier Ltd. All rights reserved. (AU)

• Processo FAPESP: 14/14690-1 - Desenvolvimento e aperfeiçoamento de capacitores eletroquímicos contendo líquidos iônicos como eletrólitos
• Beneficiário: Vitor Leite Martins
• Modalidade de apoio: Bolsas no Exterior - Estágio de Pesquisa - Pós-Doutorado
• Processo FAPESP: 13/22748-7 - Desenvolvimento de Capacitores Eletroquímicos de Alto Desempenho, Baseado em Grafeno e Líquidos Iônicos.
• Beneficiário: Vitor Leite Martins
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 15/26308-7 - Otimização das propriedades físico-químicas de materiais nano-estruturados e suas aplicações em reconhecimento molecular, catálise e conversão/armazenamento de energia
• Beneficiário: Roberto Manuel Torresi
• Modalidade de apoio: Auxílio à Pesquisa - Temático