Solid-state fuel battery

When the binary rare-earth oxide fluorides are utilized in a solid-state fuel battery, they must often withstand at a high temperature of around 1000°C to exhibit sufficient oxide ion mobility, i.e. to supply appropriate electrical current. These... 

Solar cells, furnace elements Solid state electrolytes (batteries, fuel cells, oxygen sensors)... 

Ogumi, Z. Uchimoto, Y. Takehara, Z. Kanamoii, Y. (1989). Preparation of Ultra-Thin Solid-State Lithium Batteries Utilizing a Plasma-Polymerized Solid Polymer Electrolyte. /, Chem. Soc., Chem. Commun., Vol. 21, pp. 1673-1674 Ohnishi, R. Katayama, M. Takanabe, K Kubota, J. Domen, K (2010). Niobium-Based Catalysts Prepared by Reactive Radio-Frequency Magnetron Spnitteiing and Arc Plasma Methods as Non-Noble Metal Cathode Catalysts for Polymer Electrolyte Fuel Cells. Electrochim. Acta, Vol. 55, pp. 5393-5400 Papadopoulos, N.D. Karayiarmi, H.S. Tsakiridis, P.E. Perraki, M. Hiistoforou, E. (2010). 

Solid mixed ionic-electronic conductors (MIECs) exhibit both ionic and electronic (electron-hole) conductivity. Naturally, in any material there are in principle nonzero electronic and ionic conductivities (a i, a,). It is customary to limit the use of the term MIEC to those materials in which a, and 0, 1 do not differ by more than two orders of magnitude. It is also customary to use the term MIEC if a, and Ogi are not too low (o, a i 10 S/cm). Obviously, there are no strict rules. There are processes where the minority carriers play an important role despite the fact that 0,70 1 exceeds those limits and a, aj,i< 10 S/cm. In MIECs, ion transport normally occurs via interstitial sites or by hopping into a vacant site or a more complex combination based on interstitial and vacant sites, and electronic (electron/hole) conductivity occurs via delocalized states in the conduction/valence band or via localized states by a thermally assisted hopping mechanism. With respect to their properties, MIECs have found wide applications in solid oxide fuel cells, batteries, smart windows, selective membranes, sensors, catalysis, and so on. 

The perovskite structure, ABO3 (where A represents a large cation and B a medium-size cation) is adopted by many solids and solid solutions between them can readily be prepared. Vacancy-containing systems with the perovskite structure are of interest as electrolytes in solid-state batteries and fuel cells. Typical representatives of this type of material can be made by introducing a higher valence cation into the A sites or a lower valance cation into the B sites. 

During the course of the last century, it was realized that many properties of solids are controlled not so much by the chemical composition or the chemical bonds linking the constituent atoms in the crystal but by faults or defects in the structure. Over the course of time the subject has, if anything, increased in importance. Indeed, there is no aspect of the physics and chemistry of solids that is not decisively influenced by the defects that occur in the material under consideration. The whole of the modem silicon-based computer industry is founded upon the introduction of precise amounts of specific impurities into extremely pure crystals. Solid-state lasers function because of the activity of impurity atoms. Battery science, solid oxide fuel cells, hydrogen storage, displays, all rest upon an understanding of defects in the solid matrix. 

Bridged polysilsesquioxanes having covalently bound acidic groups, introduced via modification of the disulfide linkages within the network, were studied as solid-state electrolytes for proton-exchange fuel cell applications.473 Also, short-chain polysiloxanes with oligoethylene glycol side chains, doped with lithium salts, were studied as polymer electrolytes for lithium batteries. 

Materials development and synthesis is another important dual-use type of chemistry. Developments over the past few decades include a number of elec-troitic materials and their processing, fuel cells and batteries, photoresist and semiconductor synthesis, high-performance composites (structural components) and nanocomposite materials, colloidal nanoparticle technology, solid-state lasers, and light-emitting diodes. 

The reason that solid state batteries are potentially useful is that they can perform over a wide temperature range, they have a long shelf life, and it is possible to manufacture them so that they are extremely small. Lightweight rechargeable batteries can be now be made to give sufficient power to maintain mobile phones for several days and laptop computers for several hours. They are used for backup power supplies and may eventually become useful as alternative fuel sources to power cars. 

Solid state materials that can conduct electricity, are electrochemically of interest with a view to (a) the conduction mechanism, (b) the properties of the electrical double layer inside a solid electrolyte or semiconductor, adjacent to an interface with a metallic conductor or a liquid electrolyte, (c) charge-transfer processes at such interfaces, (d) their possible application in systems of practical interest, e.g. batteries, fuel cells, electrolysis cells, and (e) improvement of their operation in these applications by modifications of the electrode surface, etc. 

J. S. Newman, Electrochemical Systems, Prentice-Hall, Englewood Cliffs, NJ, 1991 A. J. Bard and L. R. Faulkner, Electrochemical Methods. Fundamentals and Applications, John Wiley and Sons, New York, 1980 J. O M. Bockris and S. Srinivasan, Fuel Cells Their Electrochemistry, McGraw-Hill Book Company, New York, 1969 J. O M. Bockris and A. K. V. Reddy, Modern Electrochemistry, Plenum Press, New York, 1970 C. Julien, G. A. Nazri, Solid State Batteries, Kluwer Academic Publishers, Norwell, 1994 M. Winter, J. 0. Besenhard, M. E. Spahr, and P. Novak, Adv. Mater. 10 (1998) 725 F. von Sturm, Elektrochemische Stromerzeugung, VCH, Weinheim, 1969 K. J. Vetter, Electrochemical Kinetics, Academic Press, New York, 1967. 

The nonaqueous electrolyte systems mentioned in this section are solid state systems which may be very important and promising for some types of batteries and fuel cells applications. 

The electrolytic permeability is a property of any solid electrolyte, since a local equilibrium involving ions and electrons is required by - thermodynamics for any conditions close to steady-state or global equilibrium. However, it is possible to optimize the level of permeability, depending on particular applications. In many cases, the permeability is a parasitic phenomenon leading to power losses in - fuel cells and - batteries, lower efficiency of solid-state electrolyzers and -> electrochemi-... 

Solid-state electrochemistry — is traditionally seen as that branch of electrochemistry which concerns (a) the -> charge transport processes in -> solid electrolytes, and (b) the electrode processes in - insertion electrodes (see also -> insertion electrochemistry). More recently, also any other electrochemical reactions of solid compounds and materials are considered as part of solid state electrochemistry. Solid-state electrochemical systems are of great importance in many fields of science and technology including -> batteries, - fuel cells, - electrocatalysis, -> photoelectrochemistry, - sensors, and - corrosion. There are many different experimental approaches and types of applicable compounds. In general, solid-state electrochemical studies can be performed on thin solid films (- surface-modified electrodes), microparticles (-> voltammetry of immobilized microparticles), and even with millimeter-size bulk materials immobilized on electrode surfaces or investigated with use of ultramicroelectrodes. The actual measurements can be performed with liquid or solid electrolytes. 

This book is intended to provide a background and training suitable for application of impedance spectroscopy to a broad range of applications, such as corrosion, biomedical devices, semiconductors and solid-state devices, sensors, batteries, fuel cells, electrochemical capacitors, dielectric measurements, coatings, elec-trochromic materials, analytical chemistry, and imaging. The emphasis is on generally applicable fundamentals rather than on detailed treatment of applications. The reader is referred to other sources for discussion of specific applications of impedance. ... 

Solid-state electrochemistry, as a subsection of electrochemistry, emphasizes phenomena in which the properties of sohds play a dominant role. This includes phenomena involving ionically and/or electronically conducting phases (e.g., in potentiometric or conductometric chemical sensors). As far as classical electrochemical cells are concerned, one refers not only to all-solid-state cells with sohd electrolytes (e.g., ceramic fuel cells), but also to cells with hquid electrolytes, such as modern Li-based batteries in which the storage within the sohd electrode is crucial [1-3]. 

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. 

---