Electrochemical capacitors battery electrode

An electrochemical capacitor is a device that stores electrical energy in the electrical double layer that forms at the interface between an electrolytic solution and an electronic conductor. The term applies to charged carbon—carbon systems as well as carbon-battery electrode and conducting polymer electrode combinations sometimes called ultracapacitors, supercapacitors, or hybrid capacitors. 

One area where the relationship between the structure of the polymer matrix and the physical processes of the thin layer has been studied in detail is that of electrodes modified with polymer films. The polymer materials investigated in these studies include both conducting and redox polymers. Such investigations have been driven by the many potential applications for these materials. Conducting polymers have been applied in sensors, electrolytic capacitors, batteries, magnetic storage devices, electrostatic loudspeakers and artificial muscles. On the other hand, the development of electrodes coated with redox polymers have been used extensively to develop electrochemical sensors and biosensors. In this discussion,... 

The electrochemical reduction of platinum sails confined to the aqueous environments of lyotropic liquid-crystalline phases leads to the deposition of platinum films[262] that have a well defined long-ranged porous nanostructure and high specific surface areas. These results suggest that the use of liquid-crystalline plating solutions could be a versatile way to create mesoporous electrodes for batteries, fuel cells, electrochemical capacitors, and sensors. 

Electrochemical capacitors, also called supercapacitors, are very attractive electricity sources because of their high power, very long durability, and intermediate energy between the classical dielectric capacitors and batteries. The performance of a typical electrochemical capacitor is based on the accumulation of charges in the electrical double layer without faradaic reactions (no electron transfer The electrons involved in double layer charging are the delocalized conduction-band electrons of the electrode material. As shown in Fig. 23.9, an electrochemical capacitor contains one positive electrode with electron deficiency and the second one with electron excess (negative). The capacitance C of one electrode due to a pure electrostatic attraction of ions is proportional to the surface area S of the electrode-electrolyte interface, according to the formula (23.3) ... 

Various t5pes of porous carbon have been widely studied for use as electrode materials for EDLCs. Their unusual structural and electronic properties make the carbon nanostructures applicable in the electrode materials of EDLCs and batteries. The principle of electrochemical capacitors, physical adsorption/desorption of electrolyte ions in solution, was applied for water purification by using different carbon materials [108-113]. 

Porous-electrode theory has been used to describe a variety of electrochemical devices including fuel cells, batteries, separation devices, and electrochemical capacitors. In many of these systems, the electrode contains a single solid phase and a single fluid phase. Newman and Tiedemann reviewed the behavior of these flooded porous electrodes [23]. Many fuel-cell electrodes, however, contain more than one fluid phase, which introduces additional complications. Typical fuel cell catalyst layers, for example, contain both an electrolytic phase and a gas phase in addition to the solid electronically conducting phase. An earher review of gas-diffusion electrodes for fuel cells is provided by Bockris and Srinivasan [24]. 

Lee, S. W., B. M. GaUanL H. R. Byon, P. T. Hammond, and Y. Shao-Hom. 2011. Nanostructured carbon-based electrodes Bridging the gap between thin-film lithium-ion batteries and electrochemical capacitors. Energy Environmental Science 4 1972-1985. 

Brun N, Prabaharan SRS, Morcrette M, Sanchez C, Pecastaings G, Derre A, Soum A, Deleuze H, Birot M, Backov R (2009) Hard macrocellular silica Si(HIPE) foams templating micro/macroporous carbonaceous monoliths applications as lithium ion battery negative electrodes and electrochemical capacitors. Adv Funct Mater 19 3136... 

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