Applications of Electrochemical Supercapacitors

The Ragone plot also shows that although ES devices have lower energy densities than batteries and fuel cells, their power densities are 10 times greater than those of batteries and fuel cells. Several other advantages of the ES are worthy of mention  

Very short charge and discharge times, from fractions of a second to several minutes 

Life cycles exceeding 100,000 charge-discharge cycles 

Operating temperature ranging from -20°C to 55°C under various application conditions 

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Li, F. et al.. 2009. One-step synthesis of graphene-SnOj nanocomposites and its application in electrochemical supercapacitors. Nanotechnology, 20, 455-602. 

Electronically conducting polymers (ECPs) such as polyaniline (PANI), polypyrrole (PPy) and po 1 y(3.4-cthy 1 cncdi oxyth iophcnc) (PEDOT) have been applied in supercapacitors, due to their excellent electrochemical properties and lower cost than other ECPs. We demonstrated that multi-walled carbon nanotubes (CNTs) prepared by catalytic decomposition of acetylene in a solid solution are very effective conductivity additives in composite materials based on ECPs. In this paper, we show that a successful application of ECPs in supercapacitor technologies could be possible only in an asymmetric configuration, i.e. with electrodes of different nature. 

Kim, l.-H., et ah, Synthesis and characterization of electrochemically prepared ruthenium oxide on carbon nanotube film substrate for supercapacitor applications. Journal of The Electrochemical Society, 2005.152(11) p. A2170-A2178. 

Types of capacitors and mode of energy storage after Ref.206 Reprinted from B.E. Conway, Electrochemical supercapacitors. Scientific Fundamentals and Technological Applications, Kluwer Academic/Plenum Publishers, New York (1999). Copyright 1999 with permission from Kluwer Academic Pubhshers. 

In this respect, this review provides a comprehensive survey of synthetic methods and physicochemical properties of the porous carbon materials. Furthermore, as electrochemical applications of the porous carbons to electrode materials for supercapacitor, the effects of geometric heterogeneity and surface inhomogeneity on ion penetration into the pores during double-layer charging/ discharging are discussed in detail by using ac-impedance spectroscopy, current transient technique, and cyclic voltammetry. 

Carbon science and electrochemistry are interconnected since the early days of both disciplines [1]. Electrochemistry provides significant inputs for characterization and, eventually, practical applications of carbon materials, e.g. in Li-ion batteries and supercapacitors. The discovery of fullerenes and nanotubes promoted further electrochemical research on carbons in general... 

In this chapter, the electrochemical applications of various carbon materials in energy conversion, mainly lithium storage and supercapacitors, will be critically discussed taking into account their structure/nanotexture and surface functionality, with some attention for future perspectives. 

Taking into account the underestimated advantages to operate in aqueous electrolyte, it seems also important to look for other applications of carbon materials where the unique combination of electrical conductivity, surface functionality and porous texture may be useful. Such applications as electrochemical hydrogen storage [116, 117], asymmetric supercapacitors [118] open future perspectives where aU the information previously collected on other systems will be useful. 

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