Electrochemical applications rechargeable batteries

Shortly after the first synthesis of FEDOT by oxidative polymerization, the electrochemical process for the synthesis of FEDOT was foimd and filed as patent application DE 38 43 412 Al at the end of 1988 as an extension of the basic patent. i The group of J. Heinze at the University of Freibmg joined in this invention by important electrochemical, especially cyclovoltammetric, investigations. Although as early as in this patent a first technical application— rechargeable batteries— was claimed, this was not realized up to now (to the best knowledge of the authors). 

Galvanic cells in which stored chemicals can be reacted on demand to produce an electric current are termed primaiy cells. The discharging reac tion is irreversible and the contents, once exhausted, must be replaced or the cell discarded. Examples are the dry cells that activate small appliances. In some galvanic cells (called secondaiy cells), however, the reaction is reversible that is, application of an elec trical potential across the electrodes in the opposite direc tion will restore the reactants to their high-enthalpy state. Examples are rechargeable batteries for household appliances, automobiles, and many industrial applications. Electrolytic cells are the reactors upon which the electrochemical process, elec troplating, and electrowinning industries are based. 

Nawa, M., Nogami, T. and Mikawa, H., Application of activated carbon fiber fabrics to electrodes of rechargeable battery and organic electrolyte capacitor, J. Electrochem. Soc., 1984, 131(6), 1457 1459. 

I.V. Barsukov, T.I. Motronyuk, V.Z. Barsukov, V.I. Drozdik. Metal-Free 1.5V Rechargeable Batteries Steps of Optimization and Prospects for the Practical Application// In book Batteries for Portable Application and Electric Vehicles, C.F. Flolmes and A.R. Landgrebe eds., The Electrochemical Society, Inc., Pennington, NJ, 592-596 (1997). 

In this section, you learned about electrolytic cells, which convert electrical energy into chemical energy. You compared the spontaneous reactions in galvanic cells, which have positive cell potentials, with the non-spontaneous reactions in electrolytic cells, which have negative cell potentials. You then considered cells that act as both galvanic cells and electrolytic cells in some common rechargeable batteries. These batteries are an important application of electrochemistry. In the next two sections, you will learn about many more electrochemical applications. 

Before closing this chapter, it has to be emphasized that carbon materials have a wide range of structures and textures, which strongly depend on the preparation conditions. When they are applied for electrochemistry, their detailed structure and texture must be exactly understood. The following chapters will present the practical applications of various carbons in various electrochemical devices, such as lithium-ion rechargeable batteries, electric double layer capacitors, fuel cells, and primary batteries. 

In the case of ion conductive polymers, gel polymer electrolytes which consist of a polymer matrix, organic solvents and supporting electrolyte, were introduced as novel nonaqueous electrolyte systems in electrochemical applications, such as rechargeable batteries and electric double layer capacitors [3-5], Recently, considerable attention has been devoted to the application of gel poly-... 

Refs. [i] Linden D (1994) Handbook of batteries, 2nd edn. McGraw-Hill, New York, Appendix A, p A.10. [ii] Nagy Z (ed) (2005) Online electrochemistry dictionary, http //electrochem.cwru.edu/ed/dict.htm [Hi] Crompton TR (2000) Battery reference book, 3rd edn. Newnes, Oxford, p 18/7,19/13 [iv] Gates Energy Products (1998) Rechargeable batteries applications handbook. Newnes, p 158 [v] Dhameja S (2001) Electric vehicle battery systems. Newnes, p 172-173... 

There are two main kinds of rechargeable battery based on lithium chemistry the lithium-metal and the lithium-ion battery. In both the positive electrode is a lithium insertion material the negative in the former is lithium metal and in the latter it is a lithium insertion host. The reason for the application in lithium batteries of insertion electrode materials, which are electronic and ionic conductive solid matrixes (inorganic and carbon-based), is that electrochemical insertion reactions are intrinsically simple and highly reversible. 

Numerous applications of these materials were proposed from the beginning, but only a few were realized. The application of ICPs in rechargeable batteries turned out to be much more complicated and critical than most of the other possibilities. This is due to the strong electrochemical strain in this case. The reversible intrinsic redox reaction can be written for the case of p-doped (A-type) polypyrrole as... 

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