Paste electrodes

For manufacturing of positive electrodes, pastes with the following ratio of the ingredients were applied Lithium cobaltate by Merck or by "Baltiyskaya Manufaktura" (Russia) - 42,5wt%, conductive additive (acethylene soot) - 3,5wt%, PVDF - 4wt%, solvent - the balance. Aluminium foil with the thickness of 0,02 mm was used as a current collector. 

Therefore, passivation of the positive electrode by poorly conducting PbS04 can be reduced [348]. The porosity is important because it enables the expansion during the solid phase volume increase, which accompanies the transformation of Pb02 to PbS04. In the most popular construction, the electrode paste material (mixture of metallic lead with lead oxides) is held in a framework composed of lead alloys with additions of tin, antimony, selenium, and calcium [348]. Antimony improves the mechanical stability however, it increases the resistance and facilitates the selfdischarge of the battery. Better results are obtained for low antimony content and/or for lead-calcium alloys [203]. Methods of positive electrodes improvement, from the point of view of lead oxide technology have been discussed [350]. Influence of different factors on life cycle, nature, and composition of the positive active mass has been studied by Pavlov with coworkers [200, 351, 352]. 

In earlier investigations by the authors (2,3) solid sulfonic acid resins containing polyarylether and cyano substituents, (II) and (III), respectively, were prepared and used as proton-conductive membranes, electrode electrolytes, electrode paste, and in membrane electrode assemblies. 

Mixer type M agnetohydrodyna-mic micro mixer Gold electrode paste material DuPont 5734... 

Flow electrodes. Rather than move the electrode past the solution, the sample solution can be flowed past a stationary electrode. The tubular platinum electrode (Figure 5.34) and the gold micromesh flow-through electrode (Figure 5.35) are both ingenious attempts to produce electrodes that are useful for the measurement of electroactive materials in a continuously flowing stream. Ap-... 

Yamamoto and Yamamoto [8,9] showed that not only is the skin s impedance profile quite complex, but, in addition, it was demonstrated that the skin s impedance changes in a very complex manner. In particular, the skin s impedance depends on the season, the time of day at which the impedance is determined, the state of the subject studied, the site at which the impedance is measured, and the electrode paste used to make the impedance measurements. Other investigators have confirmed and amplified on these observations [10-12,14,15,17]. For example DeNuzzio and Berner [12] demonstrated the important influence that the type of electrolyte present around the electrodes have on the skin s impedance Clar et al. [10] showed that the time variation occurred not only during the day but from day to day and Panescu et al. [14] demonstrated that the average impedance of the forearm was less than that for the palm. 

A half-cell has a graphite electrode immersed in an acidic solution (pH 0) of Mn " (concentration 1.00 M) in contact with solid Mn02- A second half-cell has an acidic solution (pH 0) of H2O2 (concentration 1.00 M) in contact with a platinum electrode past which gaseous oxygen at a pressure of 1.00 atm is bubbled. The two half-cells are connected to form a galvanic cell. 

Figure 9.4 shows a cross-sectional view of a laminated-type sensor for atmospheric nitrogen oxides based on YSZ, acting as an oxidation-catalyst electrode (Ono et al., 2004). The cell was fabricated by firing YSZ sheet on which the oxidation-catalyst platinum anode and the platinum counterelectrode were screen-printed. The porosity of the electrode is adjusted by adding resin powder into each electrode paste. 

Thirty-four workers in an electrode paste plant were monitored for response to exposure (Ovrebo et al. 1994). Exposure to benzo[a]pyrene was 0.9 pg exposure to pyrene was 3.5 pg/m. ... 

Ovrebo S, Haugen A, Fjeldstad PE, et al. 1994. Biological monitoring of exposure to polycyclic aromatic hydrocarbon in an electrode paste plant. J Occup Med 36(3) 303-310. 

The use of a perfluorinated ionomer as the SPE electrode binder results in better adhesive bonding with the membrane by virtue of the fact that the binder and the membrane are of identical composition. In addition, the solvent in the electrode paste promotes "solvent welding" by softening the membrane during the application process. 

Zirconium boride electrode cells Potassium chloride electrode paste, storage batteries Lead oxide, red... 

Geddes et al. (1975a) measured the current/voltage characteristics with a 5 ms duration heavily damped sinusoidal defibrillator pulse. Standard defibrillator electrodes 3.5" in diameter (60 cm ) were used with current pulses up to 80 A. The electrodes were face-to-face at 1 cm distance with the space filled with a 8.4 Q-cm electrode paste. It was found that the impedance of both electrodes (defined as the ratio of peak voltage to peak current) at such current levels was only a fraction of 1 Q. With the usual thorax tissue impedance of about 50 Q, little energy therefore is lost in electrode polarization processes. The 0.01 Hz impedance of the same electrode pair with small linear AC current levels was found to be about 2 kQ. This shows the extreme degree of nonlinearity. 

Another hydrometallurgical process [31] consists of crushing batteries and separating metal pieces from electrodic pastes. The sludge is then solubilised in a double stage reduction process (alkaline and acid, respectively) and the purified solution is submitted to electrowinning from the fluoroborate solution onto stainless steel blank cathodes. 

For the same reason, the nickel metal powder for the electrode paste must also be very fine, typically less than 0.4 pm, and well dispersed in the paste. Very fine Ni powder (<0.4 pm) prepared by CVD and/or chemical synthesis... 

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