Electrochemistry, Batteries, and Fuel Cells

Electrochemistry is the basis of many important and modem applications and scientific developments such as nanoscale machining (fabrication of miniature devices with three dimensional control in the nanometer scale), electrochemistry at the atomic scale, scanning tunneling microscopy, transformation of energy in biological cells, selective electrodes for the determination of ions, and new kinds of electrochemical cells, batteries and fuel cells. 

The issue starts with a general introduction by Brodd and Winter to batteries and fuel cells and the associated electrochemistry. It then continues first with several papers discussing batteries and then with papers discussing fuel cells. 

Tower, Stephen. All About Electrochemistry. Available online. URL http //www.cheml.com/acad/webtext/elchem/. Accessed May 28, 2009. Part of a virtual chemistry textbook, this excellent resource explains the basics of electrochemistry, which is important in understanding how fuel cells work. Discussions include galvanic cells and electrodes, cell potentials and thermodynamics, the Nernst equation and its applications, batteries and fuel cells, electrochemical corrosion, and electrolytic cells and electrolysis. 

Modelling of Batteries and Fuel Cells, 1991. (Ed. M. Verbrugge and J. Stockel.) Hydrogen Storage Materials, Batteries, and Electrochemistry, 1992. (Ed. 

As far as electrochemical cells relevant for applications or electrochemical measurements are concerned, we must distinguish between polarization cells, galvanic cells and open-circuit cells, depending on whether an outer current flows and, if so, in which direction this occurs. Table 1.1 provides examples of the purposes for which such cells may be used. In terms of application, we can distinguish between electrochemical sensors, electrochemical actors and galvanic elements such as batteries and fuel cells. These applications offer a major driving force for dealing with solid-state electrochemistry. 

Solid-state electrochemistry is an important and rapidly developing scientific field that integrates many aspects of classical electrochemical science and engineering, materials science, solid-state chemistry and physics, heterogeneous catalysis, and other areas of physical chemistry. This field comprises - but is not limited to - the electrochemistry of solid materials, the thermodynamics and kinetics of electrochemical reactions involving at least one solid phase, and also the transport of ions and electrons in solids and interactions between solid, liquid and/or gaseous phases, whenever these processes are essentially determined by the properties of solids and are relevant to the electrochemical reactions. The range of applications includes many types of batteries and fuel cells, a variety of sensors and analytical appliances, electrochemical pumps and compressors, ceramic membranes with ionic or mixed ionic-electronic conductivity, solid-state electrolyzers and electrocatalytic reactors, the synthesis of new materials with improved properties and corrosion protection, supercapacitors, and electrochromic and memory devices. 

ELTON J. CAIRNS is Associate Director of Lawrence Berkeley Laboratory and Professor of Chemical Engineering at the University of California, Berkeley. He received B.S. degrees in chemistry and chemical engineering from Michigan Technological University and a Ph.D. in chemical engineering from the University of California, Berkeley. He has conducted electrochemical research in industrial laboratories and national laboratories. His current research emphasizes batteries and fuel cells. He has published over 120 papers and patents and is active in a number of professional societies. He is vice president of both the International Society of Electrochemistry and the Electrochemical Society. 

The physical chemistry of electrolytic solutions is a special area of physical chemistry with a large number of reference literatures. Classical descriptions are given in the books of Hamed and Owen or Robinson and Stokes. A more recent advanced treatment is found in the book of Barthel, Krienke, and Kunz. The special problems of ionic-conducting polymers and ionic solid electrolytes are described in various other reviews. Grajd described polymer electrolytes. A classical treatment of ionic solid electrolytes is the book by Rickert or the Kudo and Fueki compilation. Because these materials are used in batteries and fuel cells, there is much hterature for this research field including such detailed reviews in the book by Julien and Nazri. Another source for details and data compilations is the CRC Handbook of Solid State Electrochemistry f... 

Because electrochemistry itself an interdisciplinary field, and is a part of so many different scientific disciplines and commercial applications, it is difficult to arrive at an accurate figure for the economic worth and annual profits of the global electrochemical industry. More reliable estimates exist for particular segments of this industry in specific countries. For example, in 2008, the domestic revenues of the United States battery and fuel cell industry were about 4.9 billion, the lion s share of which was due to the battery business (in 2005, the United States fuel cell industry had revenues of about 266 million). During the final decades of the twentieth century, the electrolytic production of aluminum in the United States was about one-fifth of the world s total, but in the twenty-first century competition from such countries as Norway and Brazil, with their extensive and less expensive hydropower, has reduced the American share. 

Pollet BG, Staffell I, Shang JL (2012) Current status of hybrid, battery and fuel cell electric vehicles from electrochemistry to market prospects. Electrochim Acta 84 235-249. doi 10.1016/j.electacta.2012.03.172... 

Ionic Liquids have been proposed for many chemical reactions, as solvents and catalysts [8, 23], in electrochemistry [32], for electroplating [33], for batteries and fuel cells [7], and in photoelectrochemistry for dye-sensitized solar cells [34]. They can be used to extract natural compounds of high value and to optimize biotransformation processes that require two-phase systems. Also for pharmaceutical apphcations, they were proposed. 

Few people realize the widespread application of electrochemistry in modern life. All batteries and fuel cells can be understood in terms of electrochemistry. Any oxidation-reduction process can be considered in electrochemical terms. Corrosion of metals, nonmetals, and ceramics is electrochemistry. Many vitally important biochemical reactions involve the transfer of charge, which is electrochemistry. As the thermodynamics of charged particles are developed in this chapter, realize that these principles are widely applicable to many systems and reactions. 

It is hardly surprising that, since electrochemistry makes incursions into so much of chemistry, opinions as to what constitutes the subject are numerous. While the classification of such areas as electroplating, storage batteries and fuel cells as electrochemistry would be almost universally accepted, the position of some other areas could call forth considerable disagreement. 

Dr. Ralph J. Brodd is President of Broddarp of Nevada. He has over 40 years of experience in the technology and market aspects of the electrochemical energy conversion business. His experience includes all major battery systems, fuel cells, and electrochemical capacitors. He is a Past President of the Electrochemical Society and was elected Honorary Member in 1987. He served as Vice President and National Secretary of the International Society of Electrochemistry as well as on technical advisory committees for the National Research Council, the International Electrotechnic Commission, and NEMA and on program review committees for the Department of Energy and NASA. 

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