Supercapacitor Behavior with KCl Electrolyte

Lee, Hee Y.; Goodenough, John B

doi:10.1006/jssc.1998.8128

Cited by 1,096 publications

(788 citation statements)

References 3 publications

Supporting

Mentioning

767

Contrasting

Unclassified

Order By: Relevance

“…6,74 This contrasts with previously reported composite electrodes where the conductive additive has not also acted as binder. 44,75 In addition, the composite films are extremely porous, containing free volumes of >75 % for all mass fractions (see SI, figure S5). …”

Section: Composite Films Of Mno2 and Swntmentioning

confidence: 99%

“…This optimum loading of carbon nanotubes (5-15 wt%) is relatively low compared to the literature where (often unoptimised and therefore poorly justified) conductor contents tend to fall in the range 15-25 %. 39,44,48,49,70,[82][83][84][85] . Obviously lower conductor contents are desirable from an economic standpoint given the present relative cost of these two materials.…”

Section: Composite Supercapacitor Electrodesmentioning

confidence: 99%

“…30,39,[42][43][44][45][46] It is worth noting that such an approach is straightforward when using solution processing techniques. 6,47 Numerous researchers have shown that this strategy can result in increased capacitance by facilitating transport of charge from redox sites to the external circuit.…”

mentioning

confidence: 99%

See 2 more Smart Citations

Effect of Percolation on the Capacitance of Supercapacitor Electrodes Prepared from Composites of Manganese Dioxide Nanoplatelets and Carbon Nanotubes

et al. 2014

View full text Add to dashboard Cite

Here we demonstrate significant improvements in the performance of supercapacitor electrodes based on 2D MnO2 nano-platelets by the addition of carbon nanotubes. Electrodes based on MnO2 nano-platelets do not display high areal capacitance because the electrical properties of such films are poor, limiting the transport of charge between redox sites and the external circuit.In addition, the mechanical strength is low, limiting the achievable electrode thickness, even in the presence of binders. By adding carbon nanotubes to the MnO2-based electrodes, we have increased the conductivity by up to eight orders of magnitude, in line with percolation theory.The nanotube network facilitates charge transport, resulting in large increases in capacitance, especially at high rates, around 1 V/s. The increase in MnO2 specific capacitance scaled with nanotube content in a manner fully consistent with percolation theory. Importantly, the mechanical robustness was significantly enhanced, allowing the fabrication of electrodes that were 10 times thicker than could be achieved in MnO2-only films. This resulted in composite films with areal capacitances up to 40 times higher than could be achieved with MnO2-only electrodes.

show abstract

Section: Composite Films Of Mno2 and Swntmentioning

confidence: 99%

Section: Composite Supercapacitor Electrodesmentioning

confidence: 99%

See 1 more Smart Citation

Effect of Percolation on the Capacitance of Supercapacitor Electrodes Prepared from Composites of Manganese Dioxide Nanoplatelets and Carbon Nanotubes

et al. 2014

View full text Add to dashboard Cite

show abstract

“…So that, even that the voltammograms do not show current peaks, it does not mean that the material does not change its oxidation state. 40,41 Specific capacitance (C) values have been calculated according to equation 1:…”

Section: Wettability Studiesmentioning

confidence: 99%

“…5 An alternative low cost, non toxic and environmentally friend material is MnO 2 . [6][7][8][9] The electrochemical performance of MnO 2 -based supercapacitors and the mechanism of energy storage depend on several aspects, such as morphology, 10,11 structure 12,13 and post synthesis thermal treatment. 14 The major interest is to use MnO 2 as positive electrode together with carbon as negative electrode in hybrid systems, improving the cell voltage, thus, improving energy and power densities.…”

Section: Introductionmentioning

confidence: 99%

Macroporous MnO2 electrodes obtained by template assisted electrodeposition for electrochemical capacitors

Benedetti¹,

Petri²,

Torresi³

et al. 2010

J. Braz. Chem. Soc.

View full text Add to dashboard Cite

Eletrodos macroporosos de MnO 2 foram preparados por eletrodeposição assistida por molde de partículas esféricas coloidais de poliestireno. A molhabilidade desses filmes foi estudada por medidas de ângulo de contato. Medidas de voltametria cíclica foram realizadas com o objetivo de estudar o seu comportamento como eletrodo para supercapacitores. A capacitância específica obtida foi cerca de 60% maior que a obtida por um eletrodo liso, o que mostra que apesar de a molhabilidade do eletrodo macroporoso ser menor, ocorre alguma penetração do eletrólito pelos poros, aumentando a área eletroativa. Por fim, o eletrodo macroporoso apresentou excelente establidade eletroquímica, não sendo observada queda de capacitância após 1000 ciclos de carga e descarga.Macroporous MnO 2 electrodes prepared by template-assisted electrodeposition using spherical polystyrene colloidal particles are studied. The wettability of such electrodes by a LiClO 4 aqueous electrolyte is measured by the contact angle technique. Cyclic voltammetry experiments are performed in order to evaluate the use of these electrodes for electrochemical capacitor applications. The specific capacity obtained is about 60% higher than that obtained for flat MnO 2 surfaces showing that, in spite of the wettability being lower, some penetration of the electrolyte into the pores must occur, increasing the electroactive area with respect to the flat electrode. Furthermore, the macroporous electrode showed excellent electrochemical stability, with neither a capacitance decrease nor a loss of morphology, after 1000 cycles.Keywords: supercapacitors, manganese oxide, porous electrodes, template assisted electro deposition, wettability IntroductionLi-ion batteries are widely used as energy sources for portable electronic devices, and several studies have been carried out in order to improve their performance.1 As charge/discharge processes are limited by reaction kinetics, 2 the search for devices that can deliver high power is an active field. Electrochemical capacitors or supercapacitors are high power sources that can be fully charged/discharged in seconds because they are based on surface faradaic reactions and/or double-layer capacitance.3,4 These devices can be applied together with a battery in order to allow both high energy and power or to replace conventional capacitors based on electrical charge separation. The preparation of high surface area electrodes can improve device performance because more material is available on the surface for charge compensation as well as for energy storage. 2Concerning redox-active materials for supercapacitors, RuO 2 presents the best capacitance values. However, its high cost does not allow its use in practical applications. 5 An alternative low cost, non toxic and environmentally friend material is MnO 2 .6-9 The electrochemical performance of MnO 2 -based supercapacitors and the mechanism of energy storage depend on several aspects, such as morphology, 10,11 structure 12,13 and post synthesis thermal treatment. 14 The major in...

show abstract

Nanomaterials in Energy Storage Systems

Dong

Dunn

2009

Nanoscale Materials in Chemistry

View full text Add to dashboard Cite

Supercapacitor Behavior with KCl Electrolyte

Cited by 1,096 publications

References 3 publications

Effect of Percolation on the Capacitance of Supercapacitor Electrodes Prepared from Composites of Manganese Dioxide Nanoplatelets and Carbon Nanotubes

Effect of Percolation on the Capacitance of Supercapacitor Electrodes Prepared from Composites of Manganese Dioxide Nanoplatelets and Carbon Nanotubes

Macroporous MnO2 electrodes obtained by template assisted electrodeposition for electrochemical capacitors

Nanomaterials in Energy Storage Systems

Contact Info

Product

Resources

About