Solid electrolytes types

T. Hibino, H. Ishikawa, and S. lio, in Solid electrolytic type fuel cells for generating electricity stablely at 600°C , Application JP, 2004. 

TSC Solid electrolyte type TclK] Ti [K] Relative value of current at the maximum... 

Hasegawa, I., Tamura, S., and Imanaka, N., Solid electrolyte type nitrogen monoxide gas sensor operating at intermediate temperature region. Sens. Actuators B Chem. 108 (2005) 314-318. 

Solid-electrolyte type Capacitor type Semiconducting type... 

Primary batteries, mercury-zinc, silver-zinc, lithium solid electrolyte types. 

Duracell Deutschland Technical Division, D-5020 Frechen, Hermann-Seger-Strasse 13 Primary batteries, mercury—zinc, silver—zinc, lithium solid electrolyte types. 

Duracell UK Technical Division Duracell House Gatwick Road, Crawley RHIO 2PA Primary batteries, mercury-zinc, silver-zinc, lithium solid electrolyte types, nickel-cadmium, lithium-sulphur dioxide, lithium-manganese dioxide, zinc-air. See also Duracell (US)... 

Primary batteries, mereury-zinc, silver-zinc, lithium solid electrolyte types secondary nickel-metal hydnde. See also Duracell (UK). 

Dry cells (batteries) and fuel cells are the main chemical electricity sources. Diy cells consist of two electrodes, made of different metals, placed into a solid electrolyte. The latter facilitates an oxidation process and a flow of electrons between electrodes, directly converting chemical energy into electricity. Various metal combinations in electrodes determine different characteristics of the dry cells. For example, nickel-cadmium cells have low output but can work for several years. On the other hand, silver-zinc cells are more powerful but with a much shorter life span. Therefore, the use of a particular type of dry cell is determined by the spacecraft mission profile. Usually these are the short missions with low electricity consumption. Diy cells are simple and reliable, since they lack moving parts. Their major drawbacks are... 

A value of Rqb for an SEI lOnm thick can be estimated from its values for CPE and CSE by assuming that these solid electrolytes consist of nanometer-sized particles. Thus the expected value for / GB at 30 °C for a lOnm SEI is in the range 10-lOOQcm2, i.e., it cannot be neglected. In some cases it may be larger than the ionic (bulk) resistance of the SEI. This calculation leads us to the conclusion that 7 GB and CGB must be included in the equivalent circuits of the SEI, for both metallic lithium and for LixC6 electrodes. The equivalent circuit for a mosaic-type... 

Some further important aspects for the design of solid electrolytes and solid electrodes for battery-type applications are the following ... 

By 19884 it became obvious that the NEMCA effect, this large apparent violation of Faraday s law, is a general phenomenon not limited to a few oxidation reactions on Ag. Of key importance in understanding NEMCA came the observation that NEMCA is accompanied by potential-controlled variation in the catalyst work function.6 Its importance was soon recognized by leading electrochemists, surface scientists and catalysis researchers. Today the NEMCA effect has been studied already for more than 60 catalytic systems and does not seem to be limited to any specific type of catalytic reaction, metal catalyst or solid electrolyte, particularly in view of... 

A complete classification of electrochemical promotion (EP) studies on the basis of the type of solid electrolyte used is given in Table 4.1 of Chapter 4 together with the corresponding references. These studies are further discussed in detail in Chapters 8 to 10. 

When a solid electrolyte component is interfaced with two electronically conducting (e.g. metal) films (electrodes) a solid electrolyte galvanic cell is formed (Fig. 3.3). Cells of this type with YSZ solid electrolyte are used as oxygen sensors.8 The potential difference U R that develops spontaneously between the two electrodes (W and R designate working and reference electrode, respectively) is given by ... 

Fuel cells such as the one shown on Fig. 3.4a convert H2 to H20 and produce electrical power with no intermediate combustion cycle. Thus their thermodynamic efficiency compares favorably with thermal power generation which is limited by Carnot-type constraints. One important advantage of solid electrolyte fuel cells is that, due to their high operating temperature (typically 700° to 1100°C), they offer the possibility of "internal reforming" which permits the use of fuels such as methane without a separate external reformer.33 36... 

When other types of solid electrolyte are used, such as the Na+ conducting JT -AljCb, then the dominant electrocatalytic reaction at the tpb is ... 

Table 4.1. Electrochemical promotion studies classification based on the type of solid electrolyte...

These features are common regardless of the type of solid electrolyte and promoting ion used. It is also in general noteworthy that the electrophobicity or electrophilicity of a reaction studied under the same experimental conditions sometimes changes upon changing the solid electrolyte. 

Nevertheless there are some reactions which never change. Thus NO reduction on noble metals, a very important catalytic reaction, is in the vast majority of cases electrophilic, regardless of the type of solid electrolyte used (YSZ or P"-A1203). And practically all oxidations are electrophobic under fuel lean conditions, regardless of the type of solid electrolyte used (YSZ, p"-Al203, proton conductors, even alkaline aqueous solutions). 

An important question frequently raised in electrochemical promotion studies is the following How thick can a porous metal-electrode deposited on a solid electrolyte be in order to maintain the electrochemical promotion (NEMCA) effect The same type of analysis is applicable regarding the size of nanoparticle catalysts supported on commercial supports such as Zr02, Ti02, YSZ, Ce02 and doped Zr02 or Ti02. What is the maximum allowable size of supported metal catalyst nanoparticles in order for the above NEMCA-type metal-support interaction mechanism to be fully operative ... 

There are no specific requirements for the solid electrolytes (pellets or tubes) used in electrochemical promotion experiments. However they should be stable under the conditions of the experimental study. Also one should know the type of ionic conductivity and the possibility of appearance of mixed ionic-electronic conductivity under the conditions of electrochemical promotion. This is quite essential for the correct interpretation of results. Addresses of suppliers of solid electrolytes included in Table B.l are presented below ... 

Two types of continuous flow solid oxide cell reactors are typically used in electrochemical promotion experiments. The single chamber reactor depicted in Fig. B.l is made of a quartz tube closed at one end. The open end of the tube is mounted on a stainless steel cap, which has provisions for the introduction of reactants and removal of products as well as for the insertion of a thermocouple and connecting wires to the electrodes of the cell. A solid electrolyte disk, with three porous electrodes deposited on it, is appropriately clamped inside the reactor. Au wires are normally used to connect the catalyst-working electrode as well as the two Au auxiliary electrodes with the external circuit. These wires are mechanically pressed onto the corresponding electrodes, using an appropriate ceramic holder. A thermocouple, inserted in a closed-end quartz tube is used to measure the temperature of the solid electrolyte pellet. 

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